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Sample records for multi-detector ct findings

  1. Multi-detector CT knee arthrography - initial experience

    International Nuclear Information System (INIS)

    Thomson, J.M.Z.; Fallon, M.; Breidahl, W.H.

    2002-01-01

    Full text: Traditional plain film arthrography can achieve reasonable accuracy and is an accepted method of investigation of patients with knee pain and possible meniscal tear. Multi-detector CT can potentially provide a more detailed and accurate examination due to its high-resolution crosssectional and multi-planar capabilities. The aim of this study was to assess the accuracy of our technique. All patients who underwent a multi-detector CT knee arthrogram in an initial 8 month period were identified. Initially the referring clinician was contacted. If the patient was referred to an orthopaedic surgeon the outcome of orthopaedic review was recorded using clinical, arthroscopic and / or MRI follow-up of the patient population. One hundred and twelve patients had a Multi-detector CT knee arthrogram performed within and 8 month period. Follow-up information was received in 69.7% of patients. Of these 68.9% had orthopaedic assessment - of which 69.2% underwent a knee arthroscopy.There was total agreement of findings in 67%, agreement of meniscal findings in 67% and chondral findings in 100%. Overall, orthopaedic opinion agreed with CT findings in 76.9%. At this stage, all meniscal tears not described in the initial CT arthrogram report have in retrospect been visible. Multi-detector CT knee arthrography is an accurate and elegant technique for investigation of knee pain, providing information in a format familiar to those reporting knee MRI. There is an initial learning curve. The technique is particularly useful in chondral assessment. It is accurate for meniscal pathology, although caution and recognition of potential pitfalls is required. Copyright (2002) Blackwell Science Pty Ltd

  2. Multi-detector CT (MDCT in bowel and mesenteric injury

    Directory of Open Access Journals (Sweden)

    Vajjalla Ravikumar

    2013-04-01

    Full Text Available Objectives: To evaluate multi-detector CT (MDCT findings in bowel and mesenteric injury due to blunt abdominal trauma.Method: Retrospective evaluation of MDCT scan reports of patients admitted in Hamad Medical Corporation, Doha, Qatar with bowel and mesenteric injury during the period of January 2005 to April 2008.Results: MDCT, without using oral contrast, clearly demonstrated various specific and less specific findings of bowel and mesenteric injury.Conclusion: Multi-detector CT is an excellent diagnostic modality in bowel and mesenteric injury. Routine administration of oral contrast agent is not mandatory for initial evaluation of these patients.

  3. Multi-Detector CT Findings of Palpable Chest Wall Masses in Children: A Pictorial Essay

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Ho; Kim, Young Tong [Dept. of Radiology, Soonchunhyang University College of Medicine, Cheonan Hospital, Cheonan (Korea, Republic of); Hong, Hyun Sook [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon Hospital, Bucheon (Korea, Republic of)

    2013-03-15

    A wide variety of diseases manifest as palpable chest wall masses in children. These include normal variation, congenital anomalies, trauma, infection, axillary lymphadenopathies, soft tissue tumors and bone tumors. Given that most of these diseases are associated with chest wall deformity, diagnosis is difficult by physical examination or ultrasonography alone. However, multi-detector CT with three dimensional reconstruction is useful in the characterization and differential diagnosis of palpable chest wall lesions. In this article, we review the spectrum of palpable chest wall diseases and illustrate their multi-detector CT presentation.

  4. Multi-detector CT coronary angiographic findings of coronary-to-pulmonary artery fistula

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    Bae, Jae Seok; Park, Eun Ah; Lim, Ji Yeon; Lee, Whal [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Park, Jae Hyung [Dept. of Radiology, Myongji Hospital, Seonam University College of Medicine, Goyang (Korea, Republic of)

    2017-01-15

    To evaluate multi-detector CT (MDCT) coronary angiographic findings of coronary-to-pulmonary artery fistula (CPAF). We retrospectively reviewed images of patients with CPAF from the coronary CT angiography (CCTA) database obtained with a 64-channel MDCT between January 2008 and March 2011. We analyzed the CCTA findings for feeding arteries, fistula, association with peripulmonary arterial aneurysms, and the presence of communication between the CPAF and bronchial arteries. Fifty-five of the 15042 (0.37%) patients were diagnosed with CPAFs. The feeding artery was single (n = 18) or multiple (n = 37). The fistula had a single drainage site (n = 54) or multiple drainage sites (n = 1). The mean diameter of the fistulous opening was 2.7 ± 1.4 mm. A peripulmonary arterial aneurysm was present in 24 (44%) patients. Communication between CPAF and bronchial arteries was present in eight (14.5%) patients. MDCT coronary angiography can provide comprehensive morphologic details on CPAF and may help in presurgical or preinterventional planning.

  5. Relationship between noise, dose, and pitch in cardiac multi-detector row CT.

    Science.gov (United States)

    Primak, Andrew N; McCollough, Cynthia H; Bruesewitz, Michael R; Zhang, Jie; Fletcher, Joel G

    2006-01-01

    In spiral computed tomography (CT), dose is always inversely proportional to pitch. However, the relationship between noise and pitch (and hence noise and dose) depends on the scanner type (single vs multi-detector row) and reconstruction mode (cardiac vs noncardiac). In single detector row spiral CT, noise is independent of pitch. Conversely, in noncardiac multi-detector row CT, noise depends on pitch because the spiral interpolation algorithm makes use of redundant data from different detector rows to decrease noise for pitch values less than 1 (and increase noise for pitch values > 1). However, in cardiac spiral CT, redundant data cannot be used because such data averaging would degrade the temporal resolution. Therefore, the behavior of noise versus pitch returns to the single detector row paradigm, with noise being independent of pitch. Consequently, since faster rotation times require lower pitch values in cardiac multi-detector row CT, dose is increased without a commensurate decrease in noise. Thus, the use of faster rotation times will improve temporal resolution, not alter noise, and increase dose. For a particular application, the higher dose resulting from faster rotation speeds should be justified by the clinical benefits of the improved temporal resolution. RSNA, 2006

  6. Development of a fast multi-line x-ray CT detector for NDT

    International Nuclear Information System (INIS)

    Hofmann, T.; Nachtrab, F.; Schlechter, T.; Mühlbauer, J.; Schröpfer, S.; Firsching, M.; Uhlmann, N.; Neubauer, H.; Ernst, J.; Schweiger, T.; Oberst, M.; Meyer, A.

    2015-01-01

    Typical X-ray detectors for non-destructive testing (NDT) are line detectors or area detectors, like e.g. flat panel detectors. Multi-line detectors are currently only available in medical Computed Tomography (CT) scanners. Compared to flat panel detectors, line and multi-line detectors can achieve much higher frame rates. This allows time-resolved 3D CT scans of an object under investigation. Also, an improved image quality can be achieved due to reduced scattered radiation from object and detector themselves. Another benefit of line and multi-line detectors is that very wide detectors can be assembled easily, while flat panel detectors are usually limited to an imaging field with a size of approx. 40 × 40 cm 2 at maximum. The big disadvantage of line detectors is the limited number of object slices that can be scanned simultaneously. This leads to long scan times for large objects. Volume scans with a multi-line detector are much faster, but with almost similar image quality. Due to the promising properties of multi-line detectors their application outside of medical CT would also be very interesting for NDT. However, medical CT multi-line detectors are optimized for the scanning of human bodies. Many non-medical applications require higher spatial resolutions and/or higher X-ray energies. For those non-medical applications we are developing a fast multi-line X-ray detector.In the scope of this work, we present the current state of the development of the novel detector, which includes several outstanding properties like an adjustable curved design for variable focus-detector-distances, conserving nearly uniform perpendicular irradiation over the entire detector width. Basis of the detector is a specifically designed, radiation hard CMOS imaging sensor with a pixel pitch of 200 μ m. Each pixel has an automatic in-pixel gain adjustment, which allows for both: a very high sensitivity and a wide dynamic range. The final detector is planned to have 256 lines of

  7. Multi-detector CT assessment of traumatic renal lesions

    African Journals Online (AJOL)

    Mohamed Samir Shaaban

    2015-07-10

    Jul 10, 2015 ... Aim of the work: To demonstrate different traumatic lesions of the kidneys using multi-detector. CT, and its use in ... sis and staging of renal trauma and guiding management. © 2015 The ... Emotion 6 (Siemens, Germany), and 16 detectors PHILIPS .... with active bleeding within the hematoma and was man-.

  8. CT findings of intraductal papillary neoplasm of the bile duct: Assessment with multiphase contrast-enhanced examination using multi-detector CT

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, H., E-mail: ogawa.hiroshi@h.mbox.nagoya-u.ac.jp [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Itoh, S. [Department of Radiology, Japanese Red Cross Nagoya Daiichi Hospital, Nagoya (Japan); Nagasaka, T. [Department of Medical Technology, Nagoya University School of Health Sciences, Nagoya (Japan); Suzuki, K. [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Ota, T. [Department of Radiology, Aichi Medical University Hospital, Nagakute Aichi (Japan); Naganawa, S. [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan)

    2012-03-15

    Aim: To evaluate multi-detector computed tomography (MDCT) findings of intraductal papillary neoplasm of the bile duct (IPNB), a neoplasm that is considered to be the biliary counterpart of pancreatic intraductal papillary mucinous neoplasm. Materials and methods: Two radiologists retrospectively evaluated multiphase contrast-enhanced CT images with 0.5 or 1 mm collimation in 37 consecutive patients with resected IPNB diagnosed by a single pathologist. The CT findings were correlated with the pathological findings concerning invasion of the surrounding organs and vessels. Results: All patients showed bile duct dilatation. An intraductal mass was detected in 36 patients and the following findings were observed: extensive infiltration along the bile duct more than 20 mm (n = 32), compared with normal hepatic parenchyma, isodense or hyperdense during the late arterial phase (n = 31), not hyperdense during the portal-venous and delayed phases (n = 36), and intense enhancement rim at the base of the mass during the portal-venous or delayed phase (n = 27). Parenchymal invasion of the surrounding organs was seen in eight of 16 tumours showing irregular or bulging margins. Vascular invasion was false positive in four of eight tumours. Conclusions: IPNB exhibits relatively characteristic findings with multiphase contrast-enhanced examination using MDCT. A tendency to overestimate invasion of the surrounding organs and vessels was seen.

  9. Acute gastrointestinal bleeding: detection of source and etiology with multi-detector-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Scheffel, Hans; Pfammatter, Thomas; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Wildi, Stefan [University Hospital Zurich, Department of Visceral and Transplant Surgery, Zurich (Switzerland); Bauerfeind, Peter [University Hospital Zurich, Division of Gastroenterology, Zurich (Switzerland)

    2007-06-15

    This study was conducted to determine the ability of multi-detector-row computed tomography (CT) to identify the source and etiology of acute gastrointestinal bleeding. Eighteen patients with acute upper (n = 10) and lower (n = 8) gastrointestinal bleeding underwent 4-detector-row CT (n = 6), 16-detector-row CT (n = 11), and 64-slice CT (n = 1) with an arterial and portal venous phase of contrast enhancement. Unenhanced scans were performed in nine patients. CT scans were reviewed to determine conspicuity of bleeding source, underlying etiology, and for potential causes of false-negative prospective interpretations. Bleeding sources were prospectively identified with CT in 15 (83%) patients, and three (17%) bleeding sources were visualized in retrospect, allowing the characterization of all sources of bleeding with CT. Contrast extravasation was demonstrated with CT in all 11 patients with severe bleeding, but only in 1 of 7 patients with mild bleeding. The etiology could not be identified on unenhanced CT scans in any patient, whereas arterial-phase and portal venous-phase CT depicted etiology in 15 (83%) patients. Underlying etiology was correctly identified in all eight patients with mild GI bleeding. Multi-detector-row CT enables the identification of bleeding source and precise etiology in patients with acute gastrointestinal bleeding. (orig.)

  10. Acute gastrointestinal bleeding: detection of source and etiology with multi-detector-row CT

    International Nuclear Information System (INIS)

    Scheffel, Hans; Pfammatter, Thomas; Marincek, Borut; Alkadhi, Hatem; Wildi, Stefan; Bauerfeind, Peter

    2007-01-01

    This study was conducted to determine the ability of multi-detector-row computed tomography (CT) to identify the source and etiology of acute gastrointestinal bleeding. Eighteen patients with acute upper (n = 10) and lower (n = 8) gastrointestinal bleeding underwent 4-detector-row CT (n = 6), 16-detector-row CT (n = 11), and 64-slice CT (n = 1) with an arterial and portal venous phase of contrast enhancement. Unenhanced scans were performed in nine patients. CT scans were reviewed to determine conspicuity of bleeding source, underlying etiology, and for potential causes of false-negative prospective interpretations. Bleeding sources were prospectively identified with CT in 15 (83%) patients, and three (17%) bleeding sources were visualized in retrospect, allowing the characterization of all sources of bleeding with CT. Contrast extravasation was demonstrated with CT in all 11 patients with severe bleeding, but only in 1 of 7 patients with mild bleeding. The etiology could not be identified on unenhanced CT scans in any patient, whereas arterial-phase and portal venous-phase CT depicted etiology in 15 (83%) patients. Underlying etiology was correctly identified in all eight patients with mild GI bleeding. Multi-detector-row CT enables the identification of bleeding source and precise etiology in patients with acute gastrointestinal bleeding. (orig.)

  11. Usefulness of multiplanar reformatted images of multi-detector row helical CT in assessment of biliary stent patency

    International Nuclear Information System (INIS)

    Kim, Soo Jin; Kim, Suk; Kim, Chang Won; Lee, Jun Woo; Lee, Tae Hong; Choo, Ki Seok; Koo, Young Baek; Moon, Tae Yong; Lee, Suk Hong

    2004-01-01

    To evaluate the usefulness of multi-detector row helical CT (MDCT), multiplanar reformatted images for the noninvasive assessment of biliary stent patency, and for the planning for management in patients with a sele-expandable metallic stent due to malignant biliary obstruction. Among 90 consecutive patients, from August 1999 to July 2003, 26 cases in 23 patients with malignant biliary obstruction who underwent self-expandable metaIlic stent insertion in the biliary system and percutaneous transhepatic biliary drainage within 7 days after CT were enrolled in this study. On CT images, the complete and functional obstruction of the stent and the precise level of obstruction were evaluated. The presence of an enhancing intraluminal mass or wall thickening around stent was determined, and the causes of obstruction were evaluated. These findings were then compared with percutaneous transhepatic cholangiography. Multi-detector row helical CT correctly demonstrated the patency of a stent in 24 cases (92.3%). It was adequate in helping to depict the precise level of stent occlusion in 23 cases (88.5%). Multi-detector row helical CT also revealed the extent of tumor that represented as an enhancing intraluminal mass or wall thickening around the stent in 23 cases, and this was represented as complete obstruction on percutaneous transhepatic cholangiography. In the case of functional obstruction, MDCT predicted the possible cause of the obstruction. Multiplanar reformatted images of multi-detector row helical CT is a useful imaging modality for the noninvasive assessment of stent patency and the precise level of obstruction when stent obstruction is suspected in the patients with self-expandable metallic stent due to malignant biliary obstruction. It can also predict the possible cause of the obstruction and allows adequate planning for the medical management of such cases

  12. Usefulness of multiplanar reformatted images of multi-detector row helical CT in assessment of biliary stent patency

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soo Jin; Kim, Suk; Kim, Chang Won; Lee, Jun Woo; Lee, Tae Hong; Choo, Ki Seok; Koo, Young Baek; Moon, Tae Yong; Lee, Suk Hong [Pusan National Univ. Hospital, Busan (Korea, Republic of)

    2004-08-01

    To evaluate the usefulness of multi-detector row helical CT (MDCT), multiplanar reformatted images for the noninvasive assessment of biliary stent patency, and for the planning for management in patients with a sele-expandable metallic stent due to malignant biliary obstruction. Among 90 consecutive patients, from August 1999 to July 2003, 26 cases in 23 patients with malignant biliary obstruction who underwent self-expandable metaIlic stent insertion in the biliary system and percutaneous transhepatic biliary drainage within 7 days after CT were enrolled in this study. On CT images, the complete and functional obstruction of the stent and the precise level of obstruction were evaluated. The presence of an enhancing intraluminal mass or wall thickening around stent was determined, and the causes of obstruction were evaluated. These findings were then compared with percutaneous transhepatic cholangiography. Multi-detector row helical CT correctly demonstrated the patency of a stent in 24 cases (92.3%). It was adequate in helping to depict the precise level of stent occlusion in 23 cases (88.5%). Multi-detector row helical CT also revealed the extent of tumor that represented as an enhancing intraluminal mass or wall thickening around the stent in 23 cases, and this was represented as complete obstruction on percutaneous transhepatic cholangiography. In the case of functional obstruction, MDCT predicted the possible cause of the obstruction. Multiplanar reformatted images of multi-detector row helical CT is a useful imaging modality for the noninvasive assessment of stent patency and the precise level of obstruction when stent obstruction is suspected in the patients with self-expandable metallic stent due to malignant biliary obstruction. It can also predict the possible cause of the obstruction and allows adequate planning for the medical management of such cases.

  13. Recent technologic advances in multi-detector row cardiac CT.

    Science.gov (United States)

    Halliburton, Sandra Simon

    2009-11-01

    Recent technical advances in multi-detector row CT have resulted in lower radiation dose, improved temporal and spatial resolution, decreased scan time, and improved tissue differentiation. Lower radiation doses have resulted from the use of pre-patient z collimators, the availability of thin-slice axial data acquisition, the increased efficiency of ECG-based tube current modulation, and the implementation of iterative reconstruction algorithms. Faster gantry rotation and the simultaneous use of two x-ray sources have led to improvements in temporal resolution, and gains in spatial resolution have been achieved through application of the flying x-ray focal-spot technique in the z-direction. Shorter scan times have resulted from the design of detector arrays with increasing numbers of detector rows and through the simultaneous use of two x-ray sources to allow higher helical pitch. Some improvement in tissue differentiation has been achieved with dual energy CT. This article discusses these recent technical advances in detail.

  14. Coronary CT angiography using 64 detector rows: methods and design of the multi-centre trial CORE-64

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    Miller, Julie M.; Vavere, Andrea L.; Arbab-Zadeh, Armin; Bush, David E.; Lardo, Albert C.; Texter, John; Brinker, Jeffery; Lima, Joao A.C. [Johns Hopkins Hospital, Johns Hopkins University, Department of Medicine, Division of Cardiology, Baltimore, MD (United States); Dewey, Marc [Charite - Universitaetsmedizin Berlin, Medical School, Humboldt-Universitaet und Freie Universitaet zu Berlin, Department of Radiology, Berlin, PO Box 10098 (Germany); Rochitte, Carlos E.; Lemos, Pedro A. [University of Sao Paulo Medical School, Heart Institute (InCor), Sao Paulo (Brazil); Niinuma, Hiroyuki [Iwate Medical University, Department of Cardiology, Morioka (Japan); Paul, Narinder [Toronto General Hospital, Department of Medical Imaging, Toronto (Canada); Hoe, John [Medi-Rad Associates Ltd, CT Centre, Mt Elizabeth Hospital, Singapore (Singapore); Roos, Albert de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Yoshioka, Kunihiro [Iwate Medical University, Department of Radiology, Morioka (Japan); Cox, Christopher [Johns Hopkins Bloomberg School of Public Health, Department of Epidemiology, Baltimore, MD (United States); Clouse, Melvin E. [Harvard University, Department of Radiology, Beth Israel Deaconess, Boston, MA (United States)

    2009-04-15

    Multislice computed tomography (MSCT) for the noninvasive detection of coronary artery stenoses is a promising candidate for widespread clinical application because of its non-invasive nature and high sensitivity and negative predictive value as found in several previous studies using 16 to 64 simultaneous detector rows. A multi-centre study of CT coronary angiography using 16 simultaneous detector rows has shown that 16-slice CT is limited by a high number of nondiagnostic cases and a high false-positive rate. A recent meta-analysis indicated a significant interaction between the size of the study sample and the diagnostic odds ratios suggestive of small study bias, highlighting the importance of evaluating MSCT using 64 simultaneous detector rows in a multi-centre approach with a larger sample size. In this manuscript we detail the objectives and methods of the prospective ''CORE-64'' trial (''Coronary Evaluation Using Multidetector Spiral Computed Tomography Angiography using 64 Detectors''). This multi-centre trial was unique in that it assessed the diagnostic performance of 64-slice CT coronary angiography in nine centres worldwide in comparison to conventional coronary angiography. In conclusion, the multi-centre, multi-institutional and multi-continental trial CORE-64 has great potential to ultimately assess the per-patient diagnostic performance of coronary CT angiography using 64 simultaneous detector rows. (orig.)

  15. Multi-detector CT-colonography in inflammatory bowel disease: Prospective analysis of CT-findings to high-resolution video colonoscopy

    International Nuclear Information System (INIS)

    Andersen, Kjel; Vogt, Christoph; Blondin, Dirk; Beck, Andreas; Heinen, Wolfram; Aurich, Volker; Haeussinger, Dieter; Moedder, Ulrich; Cohnen, Mathias

    2006-01-01

    Aim: Prospective analysis of multi-detector CT-colonography (MDCTC) in patients with inflammatory bowel disease (IBD) compared to high-resolution video-endoscopy (HRVC). Materials and methods: Twenty-one patients (mean age 49.6 years) with Crohn's disease or ulcerative colitis underwent MDCTC (Somatom Volume Zoom, Siemens, Erlangen; 1 mm collimation, Pitch 8, 100 mAs, 120 kVp). HRVC was performed within 2 h after MDCTC. MDCTC was analyzed by two blinded readers. MDCTC-findings including bowel wall alterations and extraintestinal changes were compared to results of HRVC. Results: Over-all-sensitivity was 100% for endoluminal lesions with correct diagnosis of two cancers. Acute and chronic IBD were correctly identified by MDCTC in 63.6%, and 100%, respectively, with a specificity of 75%, and 100%. Sensitivity, specificity, positive and negative predictive values of MDCTC for diagnosis of acute and chronic disease were best for chronic disease. Sensitivity was worst for acute ulcerative colitis and specificity was worst for acute Crohn's disease. Haustral loss was seen only in ulcerative colitis. Pseudopolyps and fistulae were findings exclusive to Crohn's disease. Particularly extraintestinal findings as increased vascularization and local lymphadenopathy correlated well with endoscopic definition of acute disease. Because of the possibly more vulnerable colonic wall in acute inflammatory bowel disease, the air inflation for MDCTC should be performed most carefully to avoid any risk of colonic perforation. Conclusion: MDCTC may help to distinguish between patients with acute and chronic IBD. Especially extraintestinal complications, tumorous as well as pseudo-tumorous lesions can be detected with high sensitivity and specificity

  16. Comparison of CT numbers between cone-beam CT and multi-detector CT

    International Nuclear Information System (INIS)

    Kim, Dong Soo; Han, Won Jeong; Kim, Eun Kyung

    2010-01-01

    To compare the CT numbers on 3 cone-beam CT (CBCT) images with those on multi-detector CT (MDCT) image using CT phantom and to develop linear regressive equations using CT numbers to material density for all the CT scanner each. Mini CT phantom comprised of five 1 inch thick cylindrical models with 1.125 inches diameter of materials with different densities (polyethylene, polystyrene, plastic water, nylon and acrylic) was used. It was scanned in 3 CBCTs (i-CAT, Alphard VEGA, Implagraphy SC) and 1 MDCT (Somatom Emotion). The images were saved as DICOM format and CT numbers were measured using OnDemand 3D. CT numbers obtained from CBCTs and MDCT images were compared and linear regression analysis was performed for the density, ρ(g/cm 3 ), as the dependent variable in terms of the CT numbers obtained from CBCTs and MDCT images. CT numbers on i-CAT and Implagraphy CBCT images were smaller than those on Somatom Emotion MDCT image (p<0.05). Linear relationship on a range of materials used for this study were ρ=0.001 H+1.07 with R2 value of 0.999 for Somatom Emotion, ρ=0.002 H+1.09 with R2 value of 0.991 for Alphard VEGA, ρ=0.001 H+1.43 with R2 value of 0.980 for i-CAT and ρ=0.001 H+1.30 with R2 value of 0.975 for Implagraphy. CT numbers on i-CAT and Implagraphy CBCT images were not same as those on Somatom Emotion MDCT image. The linear regressive equations to determine the density from the CT numbers with very high correlation coefficient were obtained on three CBCT and MDCT scan.

  17. Comparison of CT numbers between cone-beam CT and multi-detector CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Soo; Han, Won Jeong; Kim, Eun Kyung [Department of Oral and Maxillofacial Radiology, School of Dentistry, Dankook University, Cheonan (Korea, Republic of)

    2010-06-15

    To compare the CT numbers on 3 cone-beam CT (CBCT) images with those on multi-detector CT (MDCT) image using CT phantom and to develop linear regressive equations using CT numbers to material density for all the CT scanner each. Mini CT phantom comprised of five 1 inch thick cylindrical models with 1.125 inches diameter of materials with different densities (polyethylene, polystyrene, plastic water, nylon and acrylic) was used. It was scanned in 3 CBCTs (i-CAT, Alphard VEGA, Implagraphy SC) and 1 MDCT (Somatom Emotion). The images were saved as DICOM format and CT numbers were measured using OnDemand 3D. CT numbers obtained from CBCTs and MDCT images were compared and linear regression analysis was performed for the density, {rho}(g/cm{sup 3}), as the dependent variable in terms of the CT numbers obtained from CBCTs and MDCT images. CT numbers on i-CAT and Implagraphy CBCT images were smaller than those on Somatom Emotion MDCT image (p<0.05). Linear relationship on a range of materials used for this study were {rho}=0.001 H+1.07 with R2 value of 0.999 for Somatom Emotion, {rho}=0.002 H+1.09 with R2 value of 0.991 for Alphard VEGA, {rho}=0.001 H+1.43 with R2 value of 0.980 for i-CAT and {rho}=0.001 H+1.30 with R2 value of 0.975 for Implagraphy. CT numbers on i-CAT and Implagraphy CBCT images were not same as those on Somatom Emotion MDCT image. The linear regressive equations to determine the density from the CT numbers with very high correlation coefficient were obtained on three CBCT and MDCT scan.

  18. A novel APD-based detector module for multi-modality PET/SPECT/CT scanners

    International Nuclear Information System (INIS)

    Saoudi, A.; Lecomte, R.

    1999-01-01

    The lack of anatomical information in SPECT and PET images is one of the major factors limiting the ability to localize and accurately quantify radionuclide uptake in small regions of interest. This problem could be resolved by using multi-modality scanners having the capability to acquire anatomical and functional images simultaneously. The feasibility of a novel detector suitable for measuring high-energy annihilation radiation in PET, medium-energy γ-rays in SPECT and low-energy X-rays in transmission CT is demonstrated and its performance is evaluated for potential use in multi-modality PET/SPECT/CT imaging. The proposed detector consists of a thin CsI(Tl) scintillator sitting on top of a deep GSO/LSO pair read out by an avalanche photodiode. The GSO/LOS pair provides depth-of-interaction information for 511 keV detection in PET, while the thin CsI(Tl) that is essentially transparent to annihilation radiation is used for detecting lower energy X- and γ-rays. The detector performance is compared to that of an LSO/YSO phoswich. Although the implementation of the proposed GSO/LSO/CsI(Tl) detector raises special problems that increase complexity, it generally outperforms the LSO/YSO phoswich for simultaneous PET, SPECT and CT imaging

  19. Current status of multi-detector row helical CT in imaging of adult ...

    African Journals Online (AJOL)

    Current status of multi-detector row helical CT in imaging of adult acquired pancreatic diseases and assessing surgical neoplastic resectability. ... The presence of inflammation, masses, and vascular invasion was evaluated and interpreted images were obtained during each phase. Results were compared with surgery, ...

  20. Multi-detector CT imaging in the postoperative orthopedic patient with metal hardware

    International Nuclear Information System (INIS)

    Vande Berg, Bruno; Malghem, Jacques; Maldague, Baudouin; Lecouvet, Frederic

    2006-01-01

    Multi-detector CT imaging (MDCT) becomes routine imaging modality in the assessment of the postoperative orthopedic patients with metallic instrumentation that degrades image quality at MR imaging. This article reviews the physical basis and CT appearance of such metal-related artifacts. It also addresses the clinical value of MDCT in postoperative orthopedic patients with emphasis on fracture healing, spinal fusion or arthrodesis, and joint replacement. MDCT imaging shows limitations in the assessment of the bone marrow cavity and of the soft tissues for which MR imaging remains the imaging modality of choice despite metal-related anatomic distortions and signal alteration

  1. Three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT: applications and limitations

    International Nuclear Information System (INIS)

    Kim, Su Yeon; Choi, Sun Seob; Kang, Myung Jin; Shin, Tae Beom; Lee, Ki Nam; Kang, Myung Koo

    2005-01-01

    This study was conducted to know the applications and limitations of three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT. This study examined 25 patients who underwent temporal bone CT using a 16-row detector CT as a result of hearing problems or trauma. The axial CT scan of the temporal bone was performed with a 0.6 mm collimation, and a reconstruction was carried out with a U70u sharp of kernel value, a 1 mm thickness and 0.5-1.0 mm increments. After observing the ossicles in the axial and coronal images, virtual endoscopy was performed using a three dimensional volume rendering technique with a threshold value of-500 HU. The intra-operative otoendoscopy was performed in 12 ears, and was compared with the virtual endoscopy findings. Virtual endoscopy of the 29 ears without hearing problems demonstrated hypoplastic or an incomplete depiction of the stapes superstructures in 25 ears and a normal depiction in 4 ears. Virtual endoscopy of 21 ears with hearing problems demonstrated no ossicles in 1 ears, no malleus in 3 ears, a malleoincudal subluxation in 6 ears, a dysplastic incus in 5 ears, an incudostapedial subluxation in 9 ears, dysplastic stapes in 2 ears, a hypoplastic or incomplete depiction of the stapes in 16 ears and no stapes in 1 ears. In contrast to the intra-operative otoendoscopy, 8 out of 12 ears showed a hypoplastic or deformed stapes in the virtual endoscopy. Volume rendering virtual endoscopy using a multi-row detector CT is an excellent method for evaluation the ossicles in three dimension, even thought the partial volume effect for the stapes superstructures needs to be considered

  2. Neutron CT with a multi-detector system leading to drastical reduction of the measuring time

    International Nuclear Information System (INIS)

    Hehn, G.; Pfister, G.; Schatz, A.; Goebel, J.; Kofler, R.

    1993-09-01

    By means of numerical simulation methods and their verification with measurements it could be shown that such a detector system can be realized for a line beam and 1-2 detectors per cm. With the maximum available beam width of the fast neutron field at the FRM approximately 20 detectors can be used leading to a reduction of the measuring time to 0,5 - 1 hour. A multi detector system for a line beam of thermal neutrons was constructed, tested and used for CT-measurements. This detector system for the measurement of thinner layers with better spatial resolution could be realized. The electronic discrimination between neutrons and gamma rays has been improved. This discrimination was used in all CT-measurements to get transmission values of both kinds of radiation and to reconstruct to complementary CT-images. The use of a polyenergetic radiation causes spectral shifts in the transmission spectrum leading to artifacts in the reconstructed CT-image. The transmission values must be spectral corrected before image reconstruction, because the image artifacts complicate the image evaluation or make it impossible. A new energy selective procedure for the online spectral correction was developed. This method is based on the concept to measure additionally to the integral transmission value his pulse height spectrum and to do the correction depending on the changes in this pulse height spectrum. (orig./HP) [de

  3. Slice sensitivity profiles and pixel noise of multi-slice CT in comparison with single-slice CT

    International Nuclear Information System (INIS)

    Schorn, C.; Obenauer, S.; Funke, M.; Hermann, K.P.; Kopka, L.; Grabbe, E.

    1999-01-01

    Purpose: Presentation and evaluation of slice sensitivity profile and pixel noise of multi-slice CT in comparison to single-slice CT. Methods: Slice sensitivity profiles and pixel noise of a multi-slice CT equiped with a 2D matrix detector array and of a single-slice CT were evaluated in phantom studies. Results: For the single-slice CT the width of the slice sensitivity profiles increased with increasing pitch. In spite of a much higher table speed the slice sensitivity profiles of multi-slice CT were narrower and did not increase with higher pitch. Noise in single-slice CT was independent of pitch. For multi-slice CT noise increased with higher pitch and for the higher pitch decreased slightly with higher detector row collimation. Conclusions: Multi-slice CT provides superior z-resolution and higher volume coverage speed. These qualities fulfill one of the prerequisites for improvement of 3D postprocessing. (orig.) [de

  4. Detection of intracranial aneurysms using multi-detector row CT 3D-angiography: comparison with operative findings

    Energy Technology Data Exchange (ETDEWEB)

    Han, You Mie; Lim, Soo Mee; Seo, Eui Kyo; Kim, Yoo Kyung [Mokdong Hospital, Ewha Womans University, Seoul (Korea, Republic of)

    2006-04-15

    To assess the efficacy of three-dimensional CT angiography (3D-CTA) using multi-detector row computed tomography (MDCT) in the evaluation of intracranial aneurysms in patients with non-traumatic acute subarachnoid hemorrhage and to describe those aneurysms which were not found 3D-CTA. 3D-CTA was done in 40 patients with non-traumatic subarachnoid hemorrhage by using a 16-slice MDCT; conventional digital subtraction angiography (DSA) was done in 36 of those patients within 12 hours. The CT and DSA images were reviewed by two radiologists and the site, size and neck of the aneurysms were evaluated. The results from these two modalities were then compared with the operative findings. We calculated the detection rates by 3D-CTA and DSA and evaluated the size differences of aneurysms diagnosed with 3D-DTA and those found at surgery. We also analyzed the locations and sizes of aneurysms missed by 3D-CTA and attempted to explain these false negatives. A total of 55 aneurysms were surgically confirmed in 40 patients. 48 of these were detected pre-operatively by 3D-CTA. Thus, the detection rate by 3D-CTA was 87%. The size difference of aneurysms as calculated by 3-D CTA and found operatively was as follows: less than 1 mm in 17 cases, within 1-2 mm in 15 cases, and more than 2 mm in 16 cases. Seven aneurysms were not detected by 3D-CTA. The major cause of these missed aneurysms was their small size. The undetected aneurysms were less than 2 mm in size, except for 2 instances of PCoA aneurysms. One case was not detected due to difficult image evaluation. A possible explanation of the one remaining missed aneurysms was the filling of the aneurismal sac by thrombosis. Though there were some limitations in the detection of aneurysms, 3D-CTA using 16-channel MDCT may provide sufficient pre-operative information for the management of patients with intracranial aneurysms in cases of emergency operations or DSA-failure.

  5. Detection of intracranial aneurysms using multi-detector row CT 3D-angiography: comparison with operative findings

    International Nuclear Information System (INIS)

    Han, You Mie; Lim, Soo Mee; Seo, Eui Kyo; Kim, Yoo Kyung

    2006-01-01

    To assess the efficacy of three-dimensional CT angiography (3D-CTA) using multi-detector row computed tomography (MDCT) in the evaluation of intracranial aneurysms in patients with non-traumatic acute subarachnoid hemorrhage and to describe those aneurysms which were not found 3D-CTA. 3D-CTA was done in 40 patients with non-traumatic subarachnoid hemorrhage by using a 16-slice MDCT; conventional digital subtraction angiography (DSA) was done in 36 of those patients within 12 hours. The CT and DSA images were reviewed by two radiologists and the site, size and neck of the aneurysms were evaluated. The results from these two modalities were then compared with the operative findings. We calculated the detection rates by 3D-CTA and DSA and evaluated the size differences of aneurysms diagnosed with 3D-DTA and those found at surgery. We also analyzed the locations and sizes of aneurysms missed by 3D-CTA and attempted to explain these false negatives. A total of 55 aneurysms were surgically confirmed in 40 patients. 48 of these were detected pre-operatively by 3D-CTA. Thus, the detection rate by 3D-CTA was 87%. The size difference of aneurysms as calculated by 3-D CTA and found operatively was as follows: less than 1 mm in 17 cases, within 1-2 mm in 15 cases, and more than 2 mm in 16 cases. Seven aneurysms were not detected by 3D-CTA. The major cause of these missed aneurysms was their small size. The undetected aneurysms were less than 2 mm in size, except for 2 instances of PCoA aneurysms. One case was not detected due to difficult image evaluation. A possible explanation of the one remaining missed aneurysms was the filling of the aneurismal sac by thrombosis. Though there were some limitations in the detection of aneurysms, 3D-CTA using 16-channel MDCT may provide sufficient pre-operative information for the management of patients with intracranial aneurysms in cases of emergency operations or DSA-failure

  6. Evaluation of aortogenic embolic stroke using multi-detector row CT (MDCT)

    International Nuclear Information System (INIS)

    Mizuno, Masanori; Ooura, Kazumasa; Yamaguchi, Mao; Katsura, Noriyuki; Terayama, Yasuo

    2010-01-01

    Transesophageal cardioechography is one of the useful tools for detecting aortic arteriosclerosis causing aortogenic cerebral embolism. However, it is difficult to perform this method to all of the patients because of the technical difficulties due to patient's condition, especially the severity of atherosclerosis. To avoid the unexpected and adverse events, we are routinely applying multi-detector row CT (MDCT) to those patients. Among 10 cerebral embolic patients with unidentified embolic origin, MDCT revealed arteriosclerotic changes in aorta inducing mobile thrombus in 3 cases. The above data indicates that MDCT is safe and useful tool for diagnosis of aortogenic embolic stroke. (author)

  7. Serial CT Findings of Paragonimus Infested Dogs and the Micro-CT Findings of the Worm Cysts

    International Nuclear Information System (INIS)

    Lee, Chang Hyun; Im, Jung Gi; Goo, Jin Mo; Lee, Hyun Ju; Hong, Sung Tae; Shen, Cheng Hua; Chung, Doo Hyun; Son, Kyu Ri; Chang, Jung Min; Eo, Hong

    2007-01-01

    To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. The initial findings were pleural effusion and/or subpleural groundglass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus

  8. Novel ultrahigh resolution data acquisition and image reconstruction for multi-detector row CT

    International Nuclear Information System (INIS)

    Flohr, T. G.; Stierstorfer, K.; Suess, C.; Schmidt, B.; Primak, A. N.; McCollough, C. H.

    2007-01-01

    We present and evaluate a special ultrahigh resolution mode providing considerably enhanced spatial resolution both in the scan plane and in the z-axis direction for a routine medical multi-detector row computed tomography (CT) system. Data acquisition is performed by using a flying focal spot both in the scan plane and in the z-axis direction in combination with tantalum grids that are inserted in front of the multi-row detector to reduce the aperture of the detector elements both in-plane and in the z-axis direction. The dose utilization of the system for standard applications is not affected, since the grids are moved into place only when needed and are removed for standard scanning. By means of this technique, image slices with a nominal section width of 0.4 mm (measured full width at half maximum=0.45 mm) can be reconstructed in spiral mode on a CT system with a detector configuration of 32x0.6 mm. The measured 2% value of the in-plane modulation transfer function (MTF) is 20.4 lp/cm, the measured 2% value of the longitudinal (z axis) MTF is 21.5 lp/cm. In a resolution phantom with metal line pair test patterns, spatial resolution of 20 lp/cm can be demonstrated both in the scan plane and along the z axis. This corresponds to an object size of 0.25 mm that can be resolved. The new mode is intended for ultrahigh resolution bone imaging, in particular for wrists, joints, and inner ear studies, where a higher level of image noise due to the reduced aperture is an acceptable trade-off for the clinical benefit brought about by the improved spatial resolution

  9. Congenital heart diseases: post-operative appearance on multi-detector CT - a pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Tomasian, Anderanik; Malik, Sachin; Shamsa, Kamran; Krishnam, Mayil S. [UCLA Medical Center, Department of Radiological Science, Los Angeles, CA (United States)

    2009-12-15

    Echocardiography is considered as an initial imaging modality of choice in patients with congenital heart disease (CHD), and magnetic resonance (MR) imaging is preferred for detailed functional information. Multi-detector computed tomography (CT) plays an important role in clinical practice in assessing post-operative morphological and functional information of patients with complex CHD when echocardiography and MR imaging are not contributory. Radiologists should understand and become familiar with the complex morphology and physiology of CHD, as well as with various palliative and corrective surgical procedures performed in these patients, to obtain CT angiograms with diagnostic quality and promptly recognise imaging features of normal post-operative anatomy and complications of these complex surgeries. (orig.)

  10. 16-slice multi-detector row CT coronary angiography: image quality and optimization of the image reconstruction window

    International Nuclear Information System (INIS)

    Kim, Yoo Kyung; Shim, Sung Shine; Lim, Soo Mee; Hwang, Ji Young; Kim, Yoon Kyung

    2005-01-01

    The purpose of this experiment is to investigate the image quality of CT coronary angiography using a 16-slice multi-detector row CT and to determine the optimal image reconstruction window. CT coronary angiography was obtained in 36 nonsymptomatic volunteers using a 16-slice multi-detector row CT (SOMATOM Sensation, Siemens Medical System). The mean heart rates were 70 beats per minute (bpm) or less in 18 persons and more than 70 bpm in 18 persons. Eleven data sets were obtained for each patient (reconstructed at 30%-80% of the cardiac cycle with an increment of 5%). Image quality of the eight coronary segments [left main coronary artery (LM), proximal and middle segments of left anterior descending artery (p-LAD, m-LAN) and left circumflex coronary artery (p-LCx, m-LCx) and proximal, middle and distal segments of right coronary artery (p-RCA, m-RCA, d-RCA)] was assessed. The optimal reconstruction windows in the cardiac cycle for the best image quality were 60-70% for the segments of the LM, LAD, and LC arteries in two groups (bpm 70) and 55-65% (bpm 70) for the segments of the RCA. On the best dataset for each coronary segment, the following diagnostic image quality was achieved in the two groups: LM: 100%, 83%; p-LAD: 100%, 88% m-LAD: 100%, 72%; p-LCx: 100%, 72%; m-LCx: 100%, 72%; p-RCA: 94%, 72%; m-RCA: 61%, 50%; d-RCA: 100%, 80%. The 16 slice multi-detector row CT scan provided visualization of the coronary arteries with high resolution. Especially in the group with a mean heart rate of 70 bpm or less, all the coronary segments except the RCA showed diagnostic image quality. Optimal image quality was achieved with a 60-70% trigger delay for all coronary arterial segments, but the best images of RCA were achieved in the earlier cardiac phase in the patients with a mean heart rate of more than 70 bpm

  11. Multi-detector row computed tomography angiography of peripheral arterial disease

    International Nuclear Information System (INIS)

    Kock, Marc C.J.M.; Dijkshoorn, Marcel L.; Pattynama, Peter M.T.; Myriam Hunink, M.G.

    2007-01-01

    With the introduction of multi-detector row computed tomography (MDCT), scan speed and image quality has improved considerably. Since the longitudinal coverage is no longer a limitation, multi-detector row computed tomography angiography (MDCTA) is increasingly used to depict the peripheral arterial runoff. Hence, it is important to know the advantages and limitations of this new non-invasive alternative for the reference test, digital subtraction angiography. Optimization of the acquisition parameters and the contrast delivery is important to achieve a reliable enhancement of the entire arterial runoff in patients with peripheral arterial disease (PAD) using fast CT scanners. The purpose of this review is to discuss the different scanning and injection protocols using 4-, 16-, and 64-detector row CT scanners, to propose effective methods to evaluate and to present large data sets, to discuss its clinical value and major limitations, and to review the literature on the validity, reliability, and cost-effectiveness of multi-detector row CT in the evaluation of PAD. (orig.)

  12. The value of unenhanced multi-detector computed tomography ...

    African Journals Online (AJOL)

    Introduction: Unenhanced computed tomography (CT) is used to detect urinary tract calculi with high accuracy. The development of multi-detector CT (MDCT) allows reconstructions in coronal, sagittal and oblique directions. Objective: To compare MDCT with three-dimensional (3D) ultrasound (US) imaging in evaluating ...

  13. Diagnosis of deep vein thrombosis using multi-detector helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Masashi; Minamiguchi, Hiroki; Sahara, Shinya [Wakayama Medical Coll. (Japan)] [and others

    2002-11-01

    The purpose of this study was to evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5{+-}7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. MDHCT for the diagnosis of DVT has the advantages of wider scanning rage, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities. (author)

  14. Diagnosis of deep vein thrombosis using multi-detector helical CT

    International Nuclear Information System (INIS)

    Kimura, Masashi; Minamiguchi, Hiroki; Sahara, Shinya

    2002-01-01

    The purpose of this study was to evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5±7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. MDHCT for the diagnosis of DVT has the advantages of wider scanning rage, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities. (author)

  15. Radiation dosimetry and its influencing factors for the multi-detector/slice spiral CT

    International Nuclear Information System (INIS)

    Bai Mei; Zheng Junzheng

    2008-01-01

    The Multi-Detector/Slice Spiral Computed Tomography (MDCT/MSCT)reflects the new progress in equipment and technology for radiology. Its popularized application demonstrates its advantages for clinical diagnosis. With the continuous development and growing uses of the MDCT/MSCT, the medical exposure of the patients and public has also been increasing. Therefore, assessment of the radiation dose and radiation risk from X-CT has become an increasingly important concern that should be addressed. Thus, this paper summarizes the main characteristics of the MDCT/MSCT emphasizing particularly on the radiation dosimetry, and reviews the expressions and measures of radiation dose in the MDCT/MSCT. In addition, main factors that influence radiation dose from the MDCT/MSCT are also discussed. A proper grasp of its radiation dosimetry and assessment method can significantly help radiologists, health physicists, medical physicists, X-CT engineers and manufacturers improve the management of radiation dose while optimizing the image quality in the MDCT/MSCT. (authors)

  16. Venous variants and anomalies on routine abdominal multi-detector row CT

    International Nuclear Information System (INIS)

    Koc, Zafer; Ulusan, Serife; Oguzkurt, Levent; Tokmak, Naime

    2007-01-01

    Objective: This study aims to determine the types and prevalence rates of anatomic variations of the hepatic veins, portal vein, inferior vena cava and renal veins, and to establish statistical correlations between various anomalies and frequency differences between male and female using multi-detector row computed tomography (CT). Materials and methods: One thousand one hundred and twenty patients (588 men, 532 women) were evaluated with routine abdominal CT. Frequencies of different variants were noted and compared, and correlations between three categories of variation were tested. Results: In total, 1261 abdominal vein variants and anomalies were identified in 756 (67.5%) of 1120 patients. Six hundred and forty-two hepatic vein variants were detected in 468 (41.8%) patients. One or more inferior right hepatic veins were identified in 356 (31.8%) individuals, and tributary hepatic veins were detected in 147 (13.1%) patients. Portal vein variations and anomalies were observed in 307 (27.4%) cases. The most frequent of these was trifurcation (139 patients, 12.4%). A total of 311 inferior vena cava and renal vein variants were identified in 258 (23%) cases. Six patients (0.5%) exhibited inferior vena cava anomalies, 62 (5.5%) had circumaortic renal veins, 53 (4.7%) had retroaortic renal veins, and 210 (18.8%) had multiple renal veins. Conclusion: The prevalence of abdominal vein variations is high, and routine abdominal CT demonstrates these abnormalities very well. The data suggest that hepatic vein variants and multiple right renal veins are more frequent in women than in men, and that hepatic vein variation is correlated with portal vein variation

  17. Venous variants and anomalies on routine abdominal multi-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Koc, Zafer [Baskent University, School of Medicine, Department of Radiology, Adana (Turkey)]. E-mail: koczafer@gmail.com; Ulusan, Serife [Baskent University, School of Medicine, Department of Radiology, Adana (Turkey); Oguzkurt, Levent [Baskent University, School of Medicine, Department of Radiology, Adana (Turkey); Tokmak, Naime [Baskent University, School of Medicine, Department of Radiology, Adana (Turkey)

    2007-02-15

    Objective: This study aims to determine the types and prevalence rates of anatomic variations of the hepatic veins, portal vein, inferior vena cava and renal veins, and to establish statistical correlations between various anomalies and frequency differences between male and female using multi-detector row computed tomography (CT). Materials and methods: One thousand one hundred and twenty patients (588 men, 532 women) were evaluated with routine abdominal CT. Frequencies of different variants were noted and compared, and correlations between three categories of variation were tested. Results: In total, 1261 abdominal vein variants and anomalies were identified in 756 (67.5%) of 1120 patients. Six hundred and forty-two hepatic vein variants were detected in 468 (41.8%) patients. One or more inferior right hepatic veins were identified in 356 (31.8%) individuals, and tributary hepatic veins were detected in 147 (13.1%) patients. Portal vein variations and anomalies were observed in 307 (27.4%) cases. The most frequent of these was trifurcation (139 patients, 12.4%). A total of 311 inferior vena cava and renal vein variants were identified in 258 (23%) cases. Six patients (0.5%) exhibited inferior vena cava anomalies, 62 (5.5%) had circumaortic renal veins, 53 (4.7%) had retroaortic renal veins, and 210 (18.8%) had multiple renal veins. Conclusion: The prevalence of abdominal vein variations is high, and routine abdominal CT demonstrates these abnormalities very well. The data suggest that hepatic vein variants and multiple right renal veins are more frequent in women than in men, and that hepatic vein variation is correlated with portal vein variation.

  18. Budd-Chiari syndrome: dynamic enhancement findings with multi-slice helical CT and CT angiography analysis

    International Nuclear Information System (INIS)

    Meng Xiaochun; Shan Hong; Zhu Kangshun; Xu Chuan; Zhang Jiansheng; Liu Lingyun; Ye Binbin

    2005-01-01

    Objective: To investigate the dynamic enhancement regulations of liver and their mechanism in Budd-Chiari syndrome (BCS) by using multi-slice CT and evaluate the value of CT angiography in the diagnosis of BCS. Methods: 28 cases with BCS confirmed by digital subtraction angiography (DSA) were retrospectively analyzed. All patients underwent dynamic enhancement examinations with multi-slice CT within 1 week before DSA. The relevant vessels were reconstructed respectively with MIP, VR and MPR. Compared with the results of DSA, we analyzed the dynamic enhancement regulations of liver in BCS, estimated the value of dynamic enhancement CT exams and CTA techniques in judging the obstruction level and showing collateral vessels. Results: Of all 28 cases, CT correctly showed the obstruction level in 26 cases, and 2 had incorrect results which proved to be membranous obstruction of the inferior vena cava superior to diaphragm. In 22 cases with hepatic vein obstructions, hepatic parenchyma displayed typical patchy enhancement in 19, atypical patchy enhancement in 3.8 cases among these showed benign nodules. Simultaneously, CT showed stenosis and rigidity of portal vein branches in 20, enlargement of hepatic artery in 14, hepatic collateral vessels in 20 out of 22 cases. In 6 cases with simple obstruction of inferior vena cava, hepatic changes were not found. Collateral circulations in or out of liver corresponded to the obstruction level. Conclusion: Dynamic enhancement examinations with multi-slice CT can correctly reflect the hepatic hemodynamic changes. Transverse images, combined with CTA, can explicitly display the obstruction level of vascular lesions and collateral circulations in BCS. (authors)

  19. Study on children patient dose in single-detector and multi-detector row helical computed tomography

    International Nuclear Information System (INIS)

    Lu Heqing; Zhu Guoying; Zhuo Weihai; Liu Haikuan; Guo Changyi

    2008-01-01

    Objective: To study and evaluate the radiation dose of children patient in single-detector and multi-detector row helical CT scan. Methods: The head and body CT dose index of 21 CT scanners were tested. Then the values of CTDI w , CTDI vol and DLP were calculated combining with the parameters of routine head and chest scan for children of 0-1 year old group, 5 years old group, 10 years old group and adults. The effective doses of children of every age group and adults in routine head and chest scan were subsequently estimated from effective dose per DLP by age and the calculated values of DLP. Results: CTDI per mAs is greater in the head than that in the body. In head routine scan, the effective doses of 0-1 year old group,5 years old group and 10 year old group were 2.2, 1.3 and 1.1 mSv, respectively. In chest routine scan, the effective doses of 0-1 year old group,5 years old group and 10 years old group were 5.3, 3.1 and 3.4 mSv, respectively. Effective doses to children per mAs are equally 1.8 times higher than corresponding values for adults. The CTDI vol , DLP and effective dose to children in head routine scan for MDCT were greater those that for single-detector CT and dual- detector CT. The CTDI vol , DLP and effective dose to children in chest routine scan for MDCT and dual-detector row CT were smaller than that for single-detector row CT. Conclusions: Children me more radiation risk in CT examination as compared with adults. So we should strictly abide by justification of children CT examination, and optimize the parameters of CT scan rationally in order to reduce the radiation dose to children patient as much as possible. (authors)

  20. Comparison of effective dose for imaging of mandible between multi-detector CT and cone-beam CT

    International Nuclear Information System (INIS)

    Jeong, Dae Kyo; Lee, Sang Chul; Huh, Kyung Hoe; Yi, Won Jin; Lee, Sam Sun; Choi, Soon Chul

    2012-01-01

    The aim of this study was to compare the effective dose for imaging of mandible between multi-detector computed tomography (MDCT) and cone-beam computed tomography (CBCT). An MDCT with low dose technique was also compared with them. Thermoluminescent dosimeter (TLD) chips were placed at 25 organ sites of an anthropomorphic phantom. The mandible of the phantom was exposed using 2 different types of MDCT units (Somatom Sensation 10 for standard-dose MDCT, Somatom Emotion 6 for low-dose MDCT) and 3 different CBCT units (AZ3000CT, Implagraphy, and Kavo 3D eXaM). The radiation absorbed dose was measured and the effective dose was calculated according to the ICRP 2007 report. The effective dose was the highest for Somatom Sensation 10 (425.84 μSv), followed by AZ3000CT (332.4 μSv), Somatom Emotion 6 (199.38 μSv), and 3D eXaM (111.6 μSv); it was the lowest for Implagraphy (83.09 μSv). The CBCT showed significant variation in dose level with different device. The effective doses of MDCTs were not significantly different from those of CBCTs for imaging of mandible. The effective dose of MDCT could be markedly decreased by using the low-dose technique.

  1. Comparison of effective dose for imaging of mandible between multi-detector CT and cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Dae Kyo; Lee, Sang Chul; Huh, Kyung Hoe; Yi, Won Jin; Lee, Sam Sun; Choi, Soon Chul [School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2012-06-15

    The aim of this study was to compare the effective dose for imaging of mandible between multi-detector computed tomography (MDCT) and cone-beam computed tomography (CBCT). An MDCT with low dose technique was also compared with them. Thermoluminescent dosimeter (TLD) chips were placed at 25 organ sites of an anthropomorphic phantom. The mandible of the phantom was exposed using 2 different types of MDCT units (Somatom Sensation 10 for standard-dose MDCT, Somatom Emotion 6 for low-dose MDCT) and 3 different CBCT units (AZ3000CT, Implagraphy, and Kavo 3D eXaM). The radiation absorbed dose was measured and the effective dose was calculated according to the ICRP 2007 report. The effective dose was the highest for Somatom Sensation 10 (425.84 {mu}Sv), followed by AZ3000CT (332.4 {mu}Sv), Somatom Emotion 6 (199.38 {mu}Sv), and 3D eXaM (111.6 {mu}Sv); it was the lowest for Implagraphy (83.09 {mu}Sv). The CBCT showed significant variation in dose level with different device. The effective doses of MDCTs were not significantly different from those of CBCTs for imaging of mandible. The effective dose of MDCT could be markedly decreased by using the low-dose technique.

  2. Clinico-statistical study of preoperative examination for the dental implant using multi-detector row computed tomography

    International Nuclear Information System (INIS)

    Sekiya, Keiko; Mori, Shintaro; Sekiya, Kotaro

    2008-01-01

    In April 2006, a new affiliated hospital opened at Nihon University School of Dentistry at Matsudo, and the latest model was introduced into the department of radiology. CT examinations for preoperative dental implant going on 64 multi-detector row CT, the number of cases has increased. CT examination is useful for preoperative dental implant, and many studies of concerning clinical studies using CT images have been reported. The purpose of this study was to the clinico-statistical studies of preoperative CT examinations for dental implant at our radiology department using 64 multi-detector row CT. The subjects consisted of 5174 regions in 1312 cases of preoperative CT examinations, between April 2006 and December 2007. CT machine used was the Aquilion TM 64 (Toshiba Medical Systems, Japan), and the workstation used was the ZIOSTATION (ZIOSOFT, Japan). All of CT examinations were performed the position of implant placement and disease examined from CT findings. The following results were obtained: The 1312 cases consisted of 426 males and 886 females. Patient age ranged from 16 yrs to 86 yrs old, the average age were 55.5 yrs old. Six hundred and seventy four cases were ordered at another private dental office not our hospital, and 638 cases were ordered at our hospital. The numbers of implant placement were on the average of 3.9, and the rate got higher with age. The lesions which detected by preoperative CT examination were maxillary sinusitis, periodontitis, ectopic calcification, and mucous retention cyst. (author)

  3. Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Jaeckle, T.; Stuber, G.; Hoffmann, M.H.K.; Jeltsch, M.; Schmitz, B.L.; Aschoff, A.J. [University Hospital of Ulm, Diagnostic and Interventional Radiology, Ulm (Germany)

    2008-07-15

    The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT. (orig.)

  4. Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT

    International Nuclear Information System (INIS)

    Jaeckle, T.; Stuber, G.; Hoffmann, M.H.K.; Jeltsch, M.; Schmitz, B.L.; Aschoff, A.J.

    2008-01-01

    The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT. (orig.)

  5. Radiation dose of digital tomosynthesis for sinonasal examination: comparison with multi-detector CT.

    Science.gov (United States)

    Machida, Haruhiko; Yuhara, Toshiyuki; Tamura, Mieko; Numano, Tomokazu; Abe, Shinji; Sabol, John M; Suzuki, Shigeru; Ueno, Eiko

    2012-06-01

    Using an anthropomorphic phantom, we have investigated the feasibility of digital tomosynthesis (DT) of flat-panel detector (FPD) radiography to reduce radiation dose for sinonasal examination compared to multi-detector computed tomography (MDCT). A female Rando phantom was scanned covering frontal to maxillary sinus using the clinically routine protocol by both 64-detector CT (120 kV, 200 mAs, and 1.375-pitch) and DT radiography (80 kV, 1.0 mAs per projection, 60 projections, 40° sweep, and posterior-anterior projections). Glass dosimeters were used to measure the radiation dose to internal organs including the thyroid gland, brain, submandibular gland, and the surface dose at various sites including the eyes during those scans. We compared the radiation dose to those anatomies between both modalities. In DT radiography, the doses of the thyroid gland, brain, submandibular gland, skin, and eyes were 230 ± 90 μGy, 1770 ± 560 μGy, 1400 ± 80 μGy, 1160 ± 2100 μGy, and 112 ± 6 μGy, respectively. These doses were reduced to approximately 1/5, 1/8, 1/12, 1/17, and 1/290 of the respective MDCT dose. For sinonasal examinations, DT radiography enables dramatic reduction in radiation exposure and dose to the head and neck region, particularly to the lens of the eye. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  6. Detection of the anatomic structure and pathology in animal lung specimens: comparison of micro CT and multi-detector row CT

    International Nuclear Information System (INIS)

    Lim, Kun Young; Lee, Hyun Ju; Lee, Chang Hyun; Son, Kyu Ri; Goo, Jin Mo; Im, Jung Gi; Seo, Joon Beom

    2006-01-01

    We wanted to compare the capability of micro CT and the clinically available thin-slice multi-detector row CT (MDCT) for demonstrating fine anatomic structures and pathological lesions in formalin-fixed lung specimens. The porcine lung with shark liver oil-induced lipoid pneumonia and the canine lung with pulmonary paragonimiasis were fixed by ventilating them with formalin vapor, and they were then sliced into one-centimeter thick sections. Micro CT (section thickness, 18 micrometer) and MDCT (section thickness, 0.75 mm) images were acquired in four of the lung slices of the lipoid pneumonia specimen and in five of the lung slices of the paragonimiasis specimen. On 62 pairs of micro CT and MDCT images, 169 pairs of rectangular ROIs were manually drawn in the corresponding locations. Two chest radiologists recorded the detectability of three kinds of anatomic structures (lobular core structure, interlobular septum and small bronchiolar lumen) and two kinds of pathological lesions (ground-glass opacity and consolidation) with using a five-point scale. The statistical comparison was performed by using the Wilcoxon signed rank test. Interobserver agreement was evaluated with kappa statistics. For all observers, all the kinds of anatomic structures and pathological lesions were detected better on the micro CT images than on the MDCT images (ρ < 0.01). Agreement was fair between two observers (κ = 0.38, ρ < 0.001). The fine anatomic structures and pathological lesions of the lung were more accurately demonstrated on micro CT than on thin-slice MDCT in the inflated and fixed lung specimens

  7. Detection of the anatomic structure and pathology in animal lung specimens: comparison of micro CT and multi-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Kun Young [National Cancer Center, Goyang (Korea, Republic of); Lee, Hyun Ju; Lee, Chang Hyun; Son, Kyu Ri; Goo, Jin Mo; Im, Jung Gi [Seoul National University Hospital and the Institute of Radiation Medicine, Seoul (Korea, Republic of); Seo, Joon Beom [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2006-05-15

    We wanted to compare the capability of micro CT and the clinically available thin-slice multi-detector row CT (MDCT) for demonstrating fine anatomic structures and pathological lesions in formalin-fixed lung specimens. The porcine lung with shark liver oil-induced lipoid pneumonia and the canine lung with pulmonary paragonimiasis were fixed by ventilating them with formalin vapor, and they were then sliced into one-centimeter thick sections. Micro CT (section thickness, 18 micrometer) and MDCT (section thickness, 0.75 mm) images were acquired in four of the lung slices of the lipoid pneumonia specimen and in five of the lung slices of the paragonimiasis specimen. On 62 pairs of micro CT and MDCT images, 169 pairs of rectangular ROIs were manually drawn in the corresponding locations. Two chest radiologists recorded the detectability of three kinds of anatomic structures (lobular core structure, interlobular septum and small bronchiolar lumen) and two kinds of pathological lesions (ground-glass opacity and consolidation) with using a five-point scale. The statistical comparison was performed by using the Wilcoxon signed rank test. Interobserver agreement was evaluated with kappa statistics. For all observers, all the kinds of anatomic structures and pathological lesions were detected better on the micro CT images than on the MDCT images ({rho} < 0.01). Agreement was fair between two observers ({kappa} = 0.38, {rho} < 0.001). The fine anatomic structures and pathological lesions of the lung were more accurately demonstrated on micro CT than on thin-slice MDCT in the inflated and fixed lung specimens.

  8. Research of z-axis geometric dose efficiency in multi-detector computed tomography

    International Nuclear Information System (INIS)

    Kim, You Hyun; Kim, Moon Chan

    2006-01-01

    With the recent prevalence of helical CT and multi-slice CT, which deliver higher radiation dose than conventional CT due to overbeaming effect in X-ray exposure and interpolation technique in image reconstruction. Although multi-detector and helical CT scanner provide a variety of opportunities for patient dose reduction, the potential risk for high radiation levels in CT examination can't be overemphasized in spite of acquiring more diagnostic information. So much more concerns is necessary about dose characteristics of CT scanner, especially dose efficient design as well as dose modulation software, because dose efficiency built into the scanner's design is probably the most important aspect of successful low dose clinical performance. This study was conducted to evaluate z-axis geometric dose efficiency in single detector CT and each level multi-detector CT, as well as to compare z-axis dose efficiency with change of technical scan parameters such as focal spot size of tube, beam collimation, detector combination, scan mode, pitch size, slice width and interval. The results obtained were as follows; 1. SDCT was most highest and 4 MDCT was most lowest in z-axis geometric dose efficiency among SDCT, 4, 8, 16, 64 slice MDCT made by GE manufacture. 2. Small focal spot was 0.67-13.62% higher than large focal spot in z-axis geometric dose efficiency at MDCT. 3. Large beam collimation was 3.13-51.52% higher than small beam collimation in z-axis geometric dose efficiency at MDCT. Z-axis geometric dose efficiency was same at 4 slice MDCT in all condition and 8 slice MDCT of large beam collimation with change of detector combination, but was changed irregularly at 8 slice MDCT of small beam collimation and 16 slice MDCT in all condition with change of detector combination. 5. There was no significant difference for z-axis geometric dose efficiency between conventional scan and helical scan, and with change of pitch factor, as well as change of slice width or interval for

  9. Usefulness of multi-detector row Computed Tomography for ...

    African Journals Online (AJOL)

    A 74-year-old female underwent surgical treatment for adenocarcinoma of the pancreatic head. Preoperative multi-detector row computed tomography (MD-CT) demonstrated tumor invasion into the accessory right colic vein and the branch of the middle colic artery (MCA), which was not detected by digital subtraction ...

  10. Volumetric measurements of pulmonary nodules at multi-row detector CT: in vivo reproducibility

    International Nuclear Information System (INIS)

    Wormanns, Dag; Marheine, Anke; Beyer, Florian; Heindel, Walter; Diederich, Stefan; Kohl, Gerhard; Klotz, Ernst

    2004-01-01

    The aim of this study was to assess the in vivo measurement precision of a software tool for volumetric analysis of pulmonary nodules from two consecutive low-dose multi-row detector CT scans. A total of 151 pulmonary nodules (diameter 2.2-20.5 mm, mean diameter 7.4±4.5 mm) in ten subjects with pulmonary metastases were examined with low-dose four-detector-row CT (120 kVp, 20 mAs (effective), collimation 4 x 1 mm, normalized pitch 1.75, slice thickness 1.25 mm, reconstruction increment 0.8 mm; Somatom VolumeZoom, Siemens). Two consecutive low-dose scans covering the whole lung were performed within 10 min. Nodule volume was determined for all pulmonary nodules visually detected in both scans using the volumetry tool included in the Siemens LungCare software. The 95% limits of agreement between nodule volume measurements on different scans were calculated using the Bland and Altman method for assessing measurement agreement. Intra- and interobserver agreement of volume measurement were determined using repetitive measurements of 50 randomly selected nodules at the same scan by the same and different observers. Taking into account all 151 nodules, 95% limits of agreement were -20.4 to 21.9% (standard error 1.5%); they were -19.3 to 20.4% (standard error 1.7%) for 105 nodules <10 mm. Limits of agreement were -3.9 to 5.7% for intraobserver and -5.5 to 6.6% for interobserver agreement. Precision of in vivo volumetric analysis of nodules with an automatic volumetry software tool was sufficiently high to allow for detection of clinically relevant growth in small pulmonary nodules. (orig.)

  11. A comparative study of FDG PET/CT and enhanced multi-detector CT for detecting liver metastasis according to the size and location.

    Science.gov (United States)

    Park, Jung Mi; Kim, Il Young; Kim, Sang Won; Lee, Sang Mi; Kim, Hyun Gi; Kim, Shin Young; Shin, Hyung Chul

    2013-04-01

    The aim of this study was to compare the diagnosability between (18)F-fluorodeoxyglucose (FDG) PET/CT and enhanced multi-detector CT (MDCT) for the detection of liver metastasis (LM) according to the size and location in liver and to evaluate standard maximum standardized uptake values (SUVmax) of all liver metastatic lesions. One hundred two consecutive patients with malignancy who underwent both FDG PET/CT and MDCT for LM evaluation were retrospectively reviewed. Among them, 56 patients with LM were enrolled in this study. LM was confirmed by follow-up imaging studies after at least 6 months or by histopathology. FDG PET/CT and MDCT images were visually analyzed using three-point scale by the consensus of two radiologists and two nuclear medicine physicians. The size and location (central vs. sub-capsular) of the all liver lesions were evaluated using MDCT images. Furthermore, SUVmax of all liver lesions on FDG PET/CT images were calculated. A total of 146 liver lesions were detected by FDG PET/CT and MDCT and 142 of the lesions were diagnosed as LM. The detection rates of MDCT and FDG PET/CT for LM by visual analysis were 77 and 78%, respectively. There was no significant difference of detection rate according to the overall location and size of the lesions. However, FDG PET/CT was more sensitive than MDCT for detecting small and sub-capsular LM. The detection rate of FDG PET/CT for LM was 68% by the cutoff SUVmax of 2.7. Although the diagnosabilities of MDCT and FDG PET/CT for detecting LM were comparable, FDG PET/CT is superior to MDCT for detecting small LM located in the sub-capsular portion of liver.

  12. Multi-detector row CT colonography: effect of collimation, pitch, and orientation on polyp detection in a human colectomy specimen.

    Science.gov (United States)

    Taylor, Stuart A; Halligan, Steve; Bartram, Clive I; Morgan, Paul R; Talbot, Ian C; Fry, Nicola; Saunders, Brian P; Khosraviani, Kirosh; Atkin, Wendy

    2003-10-01

    To investigate the effects of orientation, collimation, pitch, and tube current setting on polyp detection at multi-detector row computed tomographic (CT) colonography and to determine the optimal combination of scanning parameters for screening. A colectomy specimen containing 117 polyps of different sizes was insufflated and imaged with a multi-detector row CT scanner at various collimation (1.25 and 2.5 mm), pitch (3 and 6), and tube current (50, 100, and 150 mA) settings. Two-dimensional multiplanar reformatted images and three-dimensional endoluminal surface renderings from the 12 resultant data sets were examined by one observer for the presence and conspicuity of polyps. The results were analyzed with Poisson regression and logistic regression to determine the effects of scanning parameters and of specimen orientation on polyp detection. The percentage of polyps that were detected significantly increased when collimation (P =.008) and table feed (P =.03) were decreased. Increased tube current resulted in improved detection only of polyps with a diameter of less than 5 mm. Polyps of less than 5 mm were optimally depicted with a collimation of 1.25 mm, a pitch of 3, and a tube current setting of 150 mA; polyps with a diameter greater than 5 mm were adequately depicted with 1.25-mm collimation and with either pitch setting and any of the three tube current settings. Small polyps in the transverse segment (positioned at a 90 degrees angle to the z axis of scanning) were significantly less visible than those in parallel or oblique orientations (P detector row CT is highly dependent on collimation, pitch, and, to a lesser extent, tube current. Collimation of 1.25 mm, combined with pitch of 6 and tube current of 50 mA, provides for reliable detection of polyps 5 mm or larger while limiting the effective radiation dose. Polyps smaller than 5 mm, however, may be poorly depicted with use of these settings in the transverse colon. Copyright RSNA, 2003

  13. Development of a rapid multi-line detector for industrial computed tomography

    International Nuclear Information System (INIS)

    Nachtrab, Frank; Firsching, Markus; Hofmann, Thomas; Uhlmann, Norman; Neubauer, Harald; Nowak, Arne

    2015-01-01

    In this paper we present the development of a rapid multi-row detector is optimized for industrial computed tomography. With a high frame rate, high spatial resolution and the ability to use up to 450 kVp it is particularly suitable for applications such as fast acquisition of large objects, inline CT or time-resolved 4D CT. (Contains PowerPoint slides). [de

  14. Spectral detector CT-derived virtual non-contrast images: comparison of attenuation values with unenhanced CT.

    Science.gov (United States)

    Ananthakrishnan, Lakshmi; Rajiah, Prabhakar; Ahn, Richard; Rassouli, Negin; Xi, Yin; Soesbe, Todd C; Lewis, Matthew A; Lenkinski, Robert E; Leyendecker, John R; Abbara, Suhny

    2017-03-01

    To assess virtual non-contrast (VNC) images obtained on a detection-based spectral detector CT scanner and determine how attenuation on VNC images derived from various phases of enhanced CT compare to those obtained from true unenhanced images. In this HIPAA compliant, IRB approved prospective multi-institutional study, 46 patients underwent pre- and post-contrast imaging on a prototype dual-layer spectral detector CT between October 2013 and November 2015, yielding 84 unenhanced and VNC pairs (25 arterial, 39 portal venous/nephrographic, 20 urographic). Mean attenuation was measured by one of three readers in the liver, spleen, kidneys, psoas muscle, abdominal aorta, and subcutaneous fat. Equivalence testing was used to determine if the mean difference between unenhanced and VNC attenuation was less than 5, 10, or 15 HU. VNC image quality was assessed on a 5 point scale. Mean difference between unenhanced and VNC attenuation was VNC attenuation were equivalent in all tissues except fat using a threshold of VNC overestimated the HU relative to unenhanced images. VNC image quality was rated as excellent or good in 84% of arterial phase and 85% of nephrographic phase cases, but only 40% of urographic phase. VNC images derived from novel dual layer spectral detector CT demonstrate attenuation values similar to unenhanced images in all tissues evaluated except for subcutaneous fat. Further study is needed to determine if attenuation thresholds currently used clinically for common pathology should be adjusted, particularly for lesions containing fat.

  15. Multi-detector computed tomography of acute abdomen

    International Nuclear Information System (INIS)

    Leschka, Sebastian; Alkadhi, Hatem; Wildermuth, Simon; Marincek, Borut; University Hospital of Zurich

    2005-01-01

    Acute abdominal pain is one of the most common causes for referrals to the emergency department. The sudden onset of severe abdominal pain characterising the ''acute abdomen'' requires rapid and accurate identification of a potentially life-threatening abdominal pathology to provide a timely referral to the appropriate physician. While the physical examination and laboratory investigations are often non-specific, computed tomography (CT) has evolved as the first-line imaging modality in patients with an acute abdomen. Because the new multi-detector CT (MDCT) scanner generations provide increased speed, greater volume coverage and thinner slices, the acceptance of CT for abdominal imaging has increased rapidly. The goal of this article is to discuss the role of MDCT in the diagnostic work-up of acute abdominal pain. (orig.)

  16. Diagnostic Accuracy of the Volume Rendering Images of Multi-Detector CT for the Detection of Lumbar Transverse Process Fractures

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yun Hak; Chun, Tong Jin [Dept. of Radiology, Eulji University Hospital, Daejeon (Korea, Republic of)

    2012-01-15

    To compare the accuracy of three-dimensional computed tomographic (3D CT) volume rendering techniques with axial images of multi-detector row computed tomography to identify lumbar transverse process (LTP) fractures in trauma patients. We retrospectively evaluated 42 patients with back pain as a result of blunt trauma between January and June of 2010. Two radiologists examined the 3D CT volume rendering images independently. The confirmation of a LTP fracture was based on the consensus of the axial images by the two radiologists. The results of 3D CT volume rendering images were compared with the axial images and the diagnostic powers (sensitivity, specificity, and accuracy) were calculated. Seven of the 42 patients had twenty five lumbar transverse process fractures. The diagnostic power of the 3D CT volume rendering technique is as accurate as axial images. Reader 1, sensitivity 96%, specificity 100%, accuracy 99.9%; and Reader 2 sensitivity 100%, specificity 99.8%, accuracy 99.8%. The accordance of the two radiologists was 99.8%. 3D CT volume rendering images can alternate axial images to detect lumbar transverse process fractures with good image quality.

  17. Multi-detector spiral CT study of the relationships between pulmonary ground-glass nodules and blood vessels

    International Nuclear Information System (INIS)

    Gao, Feng; Li, Ming; Ge, Xiaojun; Ren, Qingguo; Hua, Yanqing; Zheng, Xiangpeng; Chen, Yan; Lv, Fangzhen

    2013-01-01

    To investigate the relationships between pulmonary ground-glass nodules (GGN) and blood vessels and their diagnostic values in differentiating GGNs. Multi-detector spiral CT imaging of 108 GGNs was retrospectively reviewed. The spatial relationships between GGNs and supplying blood vessels were categorized into four types: I, vessels passing by GGNs; II, intact vessels passing through GGNs; III, distorted, dilated or tortuous vessels seen within GGNs; IV, more complicated vasculature other than described above. Relationship types were correlated to pathologic and/or clinical findings of GGNs. Of 108 GGNs, 10 were benign, 24 preinvasive nodules and 74 adenocarcinomas that were pathologically proven. Types I, II, III and IV vascular relationships were observed in 9, 58, 21 and 20 GGNs, respectively. Type II relationship was the dominating relationship for each GGN group, but significant differences were shown among them. Correlation analysis showed strong correlation between invasive adenocarcinoma and type III and IV relationships. Subgroup analysis indicated that type III was more commonly seen in IAC with comparison to type IV more likely seen in MIA. Different GGNs have different relationships with vessels. Understanding and recognising characteristic GGN-vessel relationships may help identify which GGNs are more likely to be malignant. (orig.)

  18. Scanning technology with multi-slice helical CT in security inspection domain

    International Nuclear Information System (INIS)

    Wang Jue; Wang Fuquan; Jiang Zenghui

    2008-01-01

    The paper analyzes the technology conditions of security inspection in home and abroad, and expatiates technology of spiral CT and how to define CT value etc, with studying on the key technology of spiral CT scanning way (X-RAY, detector, technology of pulley etc) and mutual relation. By comparing the present products of security inspection, the conclusion was drawn that it is inevitable to develop the tendency of security inspection area with the checking and discerning the substance by using the technology of multi-layer spiral CT. (authors)

  19. WE-E-18C-01: Multi-Energy CT: Current Status and Recent Innovations

    International Nuclear Information System (INIS)

    Pelc, N; McCollough, C; Yu, L; Schmidt, T

    2014-01-01

    Conventional computed tomography (CT) uses a single polychromatic x-ray spectrum and energy integrating detectors, and produces images whose contrast depends on the effective attenuation coefficient of the broad spectrum beam. This can introduce errors from beam hardening and does not produce the optimal contrast-to-noise ratio. In addition, multiple materials can have the same effective attenuation coefficient, causing different materials to be indistinguishable in conventional CT images. If transmission measurements at two or more energies are obtained, even with polychromatic beams, more specific information about the object can be obtained. If the object does not contain materials with k-edges in the spectrum, the x-ray attenuation can be well-approximated by a linear combination of two processes (photoelectric absorption and Compton scattering) or, equivalently, two basis materials. For such cases, two spectral measurements suffice, although additional measurements can provide higher precision. If K-edge materials are present, additional spectral measurements can allow these materials to be isolated. Current commercial implementations use varied approaches, including two sources operating a different kVp, one source whose kVp is rapidly switched in a single scan, and a dual layer detector that can provide spectral information in every reading. Processing of the spectral information can be performed in the raw data domain or in the image domain. The process of calculating the amount of the two basis functions implicitly corrects for beam hardening and therefore can lead to improvements in quantitative accuracy. Information can be extracted to provide material specific information beyond that of conventional CT. This additional information has been shown to be important in several clinical applications, and can also lead to more efficient clinical protocols. Recent innovations in x-ray sources, detectors, and systems have made multi-energy CT much more practical

  20. CT findings in patients with chronic thromboembolic pulmonary hypertension

    International Nuclear Information System (INIS)

    Heinrich, M.; Grgic, A.; Heckmann, M.; Kramann, B.; Tscholl, D.; Schaefers, H.J.; Uder, M.

    2005-01-01

    Chronic thromboembolic pulmonary hypertension (CTEPH) is thought to be a rare complication of pulmonary embolism. However, it was recently demonstrated that CTEPH is more common than previously thought after pulmonary embolism. Without treatment, CTEPH is associated with a very high mortality rate. Making the correct diagnosis early is essential, because there is a potential curative treatment in the form of pulmonary thromboendarterectomy (PTE). Because of the unspecific clinical symptoms of CTEPH, the different imaging modalities play a crucial role in diagnosis making. Since the introduction of the multi-detector CT technology, CT has become an important part in the diagnostic work up of pulmonary embolism and CTEPH and is often used as a first-line diagnostic tool. CT is not only a reliable tool for the diagnosis of CTEPH, but also is helpful in estimating the operability of these patients. PTE is still associated with a mortality rate of about 10%. Particularly an insufficient decrease of the pulmonary vascular resistance after PTE leads to a very high mortality rate. Therefore, it is crucial to correlate the degree of the surgical accessible obstruction of the pulmonary vasculature with the degree of pulmonary hypertension in deciding for or against PTE. The aim of this review is to describe the CT findings in patients with CTEPH and their use in differentiating CTEPH from other diseases like acute pulmonary embolism and primary pulmonary hypertension. Moreover, the correlation of different CT imaging features with surgical success after PTE will be discussed. (orig.)

  1. Using multi-detector-row CT to diagnose ampullary adenoma or adenocarcinoma in situ

    International Nuclear Information System (INIS)

    Lee, Myungsu; Kim, Myeong-Jin; Park, Mi-Suk; Choi, Jin-Young; Chung, Yong Eun

    2011-01-01

    Objective: To assess the diagnostic accuracy of multi-detector-row computed tomography (MDCT) for the detection of ampullary adenomas or adenocarcinomas in situ. Materials and methods: We retrospectively reviewed 21 computed tomography (CT) images from 20 patients with ampullary tumors, and 22 CT images from 22 patients without periampullary tumor. Three radiologists blindly and independently reviewed CT images. The sensitivities and specificities for identification of ampullary masses were calculated in all cases and in cases with adequate duodenal distension. The sensitivities and specificities for the diagnosis of ampullary tumors were calculated using the following criteria: identification of mass alone; presence of extrahepatic bile duct (EBD) dilation or identification of mass; presence of pancreatic duct (PD) dilation or identification of mass. Paired t-tests were performed to assess differences in mean values. Results: The mean sensitivity and specificity of MDCT for the detection of an ampullary mass in all cases were 47.6% and 86.4%, and in cases with adequate duodenal distension, 66.7% (p = 0.07) and 80.5% (p = 0.32), respectively. When the presence of EBD dilation or identification of mass were used as criteria, the mean sensitivity and specificity were 73.0% (p = 0.03) and 60.6% (p = 0.03), respectively. When presence of PD dilation or identification of mass were used as criteria, the mean sensitivity and specificity were 47.6% and 81.8% (p = 0.23). Conclusions: MDCT is moderately accurate for the diagnosis of ampullary adenoma or adenocarcinoma in situ. When EBD dilation or identification of mass were used as criteria, the sensitivity can be improved.

  2. Cardiac pathologies incidentally detected with non-gated chest CT; Inzidentelle Pathologien des Herzens im Thorax-CT

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, Axel; Kroepil, P.; Lanzman, R.S.; Moedder, U. [Inst. fuer Radiologie, Universitaetsklinikum Duesseldorf, Heinrich-Heine-Univ. (Germany); Choy, G.; Abbara, S. [Cardiovascular Imaging Section, Massachusetts General Hospital, Harvard Medical School (United States)

    2009-12-15

    Cardiac imaging using electrocardiogram-gated multi-detector computed tomography (MDCT) permits noninvasive diagnosis of congenital and acquired cardiac pathologies and has thus become increasingly important in the last years. Several studies investigated the incidence and relevance of incidental extracardiac structures within the lungs, mediastinum, chest wall, and abdomen with gated coronary CT. This resulted in the general acceptance of the review of extracardiac structures as a routine component of coronary CT interpretation. On the other hand radiologists tend to neglect pericardial and cardiac pathologies in non-gated chest CT, which is primarily performed for the evaluation of the respiratory system or for tumor staging. Since the introduction of multi-detector spiral CT technology, the incidental detection of cardiac and pericardial findings has become possible using non-gated chest CT. This article reviews the imaging appearances and differential diagnostic considerations of incidental cardiac entities that may be encountered in non-gated chest CT. (orig.)

  3. Acute pulmonary embolism in the era of multi-detector CT: a reality in sub-Saharan Africa

    International Nuclear Information System (INIS)

    Tambe, Joshua; Moifo, Boniface; Fongang, Emmanuel; Guegang, Emilienne; Juimo, Alain Georges

    2012-01-01

    The advantages of multi-detector computed tomography (MDCT) have made it the imaging modality of choice for some patients with suspected cardiothoracic disease, of which pulmonary embolism (PE) is an exponent. The aim of this study was to assess the incidence of PE in patients with clinical suspicion of acute PE using MDCT in a sub-Saharan setting, and to describe the demographic characteristics of these patients. Consecutive records of patients who underwent MDCT pulmonary angiography for suspected acute PE over a two-year period at the Radiology Department of a university-affiliated hospital were systematically reviewed. All MDCT pulmonary angiograms were performed with a 16-detector computed tomography (CT) scanner using real-time bolus tracking technique. Authorization for the study was obtained from the institutional authorities. Forty-one MDCT pulmonary angiograms were reviewed of which 37 were retained. Of the 4 excluded studies, 3 were repeat angiograms and 1 study was not technically adequate. Twelve of 37 patients (32.4%) had CT angiograms that were positive for PE, of which 7 were males. The mean age of these patients was 47.6±10.5 years (age range from 33 to 65 years). Twenty five patients out of 37 (67.6%) had CT angiograms that were negative for PE. Eleven PE-positive patients (91.7%) had at least 1 identifiable thromboembolic risk factor whilst 5 PE-negative patients (20%) also had at least a thromboembolic risk factor. The relative risk of the occurrence of PE in patients with at least a thromboembolic risk factor was estimated at 14.4. Acute PE is a reality in sub-Saharan Africa, with an increased likelihood of MDCT evidence in patients with clinical suspicion of PE who have at least a thromboembolic risk factor. The increasing availability of MDCT will help provide more information on the occurrence of PE in these settings

  4. Peliosis Hepatis with Hemorrhagic Necrosis and Rupture: a Case Report with Emphasis on the Multi-Detector CT Findings

    OpenAIRE

    Kim, Eun-A; Yoon, Kwon-Ha; Jeon, Se-Jung; Cai, Quan-Yu; Lee, Young-Whan; Yoon, Seong Eon; Yoon, Ki-Jung; Juhng, Seon-Kwan

    2007-01-01

    We report here on an uncommon case of peliosis hepatis with hemorrhagic necrosis that was complicated by massive intrahepatic bleeding and rupture, and treated by emergent right lobectomy. We demonstrate the imaging findings, with emphasis on the triphasic, contrast-enhanced multidetector CT findings, as well as reporting the clinical outcome in a case of peliosis hepatis with fatal hemorrhage.

  5. Abdominal multi-detector row CT: Effectiveness of determining contrast medium dose on basis of body surface area

    International Nuclear Information System (INIS)

    Onishi, Hiromitsu; Murakami, Takamichi; Kim, Tonsok; Hori, Masatoshi; Osuga, Keigo; Tatsumi, Mitsuaki; Higashihara, Hiroki; Maeda, Noboru; Tsuboyama, Takahiro; Nakamoto, Atsushi; Tomoda, Kaname; Tomiyama, Noriyuki

    2011-01-01

    Purpose: To investigate the validity of determining the contrast medium dose based on body surface area (BSA) for the abdominal contrast-enhanced multi-detector row CT comparing with determining based on body weight (BW). Materials and methods: Institutional review committee approval was obtained. In this retrospective study, 191 patients those underwent abdominal contrast-enhanced multi-detector row CT were enrolled. All patients received 96 mL of 320 mg I/mL contrast medium at the rate of 3.2 mL. The iodine dose required to enhance 1 HU of the aorta at the arterial phase and that of liver parenchyma at portal venous phase per BSA were calculated (EU BSA ) and evaluated the relationship with BSA. Those per BW were also calculated (EU BW ) and evaluated. Estimated enhancement values (EEVs) of the aorta and liver parenchyma with two protocols for dose decision based on BSA and BW were calculated and patient-to-patient variability was compared between two protocols using the Levene test. Results: The mean of EU BSA and EU BW were 0.0621 g I/m 2 /HU and 0.00178 g I/kg/HU for the aorta, and 0.342 g I/m 2 /HU and 0.00978 g I/kg/HU for the liver parenchyma, respectively. In the aortic enhancement, EU BSA was almost constant regardless of BSA, and the mean absolute deviation of the EEV with the BSA protocol was significantly lower than that with the BW protocol (P < .001), although there was no significant difference between two protocols in the hepatic parenchymal enhancement (P = .92). Conclusion: For the aortic enhancement, determining the contrast medium dose based on BSA was considered to improve patient-to-patient enhancement variability.

  6. Evaluation of 16 detector row spiral CT in diagnosing pulmonary embolism

    International Nuclear Information System (INIS)

    Yu Xiaokun; Li Lei

    2008-01-01

    Objective: To investigate the value of 16 detector row spiral CT in the diagnosis of pulmonary embolism(PE). Methods: Imaging data of 20 patients (plain 16 detector row spiral CT scanning plus enhanced scanning imaging) highly suspected of PE was retrospectively analyzed. Results: Among the 20 cases, embolism was showed in 13 patients on 16 detector row spiral CT pulmonary angiography (MSCTPA). 6 cases of the 13 PE's patients have masculine findings on plain MSCT scanning images. Localized tenuous lung markings, dilated pulmonary artery, 'mosaic' sign, pleural or pericardial effusion, local high attenuation centrally in the pulmonary arteries and lung infarction occurred respectively. Conclusion: MSCTPA may be an effective, simple and safe technique for the diagnosis of PE. It was a reliable means in defecting PE However, for the cases unfit for contrast media and cases only suitable for unenhanced CT because of nonspecific heart-pulmonary symptom, noticeable abnormal signs of plain MSCT scanning could suggest the occurrence of pulmonary embolism. (authors)

  7. Capability of abdominal 320-detector row CT for small vasculature assessment compared with that of 64-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, Kazuhiro, E-mail: kitajima@med.kobe-u.ac.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Maeda, Tetsuo; Ohno, Yoshiharu [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Division of Radiology, Kobe University Hospital, Kobe (Japan); Yoshikawa, Takeshi [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Konishi, Minoru [Division of Radiology, Kobe University Hospital, Kobe (Japan); Kanda, Tomonori; Onishi, Yumiko; Matsumoto, Keiko; Koyama, Hisanobu; Takenaka, Daisuke; Sugimura, Kazuro [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan)

    2011-11-15

    Objective: To compare the capability of 320-detector row CT (area-detector CT: ADCT) with step-and-shoot scan protocol for small abdominal vasculature assessment with that of 64-detector row CT with helical scan protocol. Materials and methods: Total of 60 patients underwent contrast-enhanced abdominal CT for preoperative assessment. Of all, 30 suspected to have lung cancer underwent ADCT using step-and-shoot scan protocol. The other 30 suspected to have renal cell carcinoma underwent 64-MDCT using helical scan protocol. Two experienced radiologists independently assessed inferior epigastric, hepatic subsegmental (in the segment 8), mesenteric marginal (Griffith point) and inferior phrenic arteries by using 5-point visual scoring systems. Kappa analysis was used for evaluation of interobserver agreement. To compare the visualization capability of the two systems, the Mann-Whitney U-test was used to compare the scores for each of the arteries. Results: Overall interobserver agreements for both systems were almost perfect ({kappa} > 0.80). Visualization scores for inferior epigastric and mesenteric arteries were significantly higher for ADCT than for 64-detector row CT (p < 0.05). No significant difference was found for hepatic subsegmental and inferior phrenic arteries. Conclusion: Small abdominal vasculature assessment by ADCT with step-and-shoot scan protocol is potentially equal to or better than that by 64-detector row CT with helical scan protocol.

  8. Capability of abdominal 320-detector row CT for small vasculature assessment compared with that of 64-detector row CT

    International Nuclear Information System (INIS)

    Kitajima, Kazuhiro; Maeda, Tetsuo; Ohno, Yoshiharu; Yoshikawa, Takeshi; Konishi, Minoru; Kanda, Tomonori; Onishi, Yumiko; Matsumoto, Keiko; Koyama, Hisanobu; Takenaka, Daisuke; Sugimura, Kazuro

    2011-01-01

    Objective: To compare the capability of 320-detector row CT (area-detector CT: ADCT) with step-and-shoot scan protocol for small abdominal vasculature assessment with that of 64-detector row CT with helical scan protocol. Materials and methods: Total of 60 patients underwent contrast-enhanced abdominal CT for preoperative assessment. Of all, 30 suspected to have lung cancer underwent ADCT using step-and-shoot scan protocol. The other 30 suspected to have renal cell carcinoma underwent 64-MDCT using helical scan protocol. Two experienced radiologists independently assessed inferior epigastric, hepatic subsegmental (in the segment 8), mesenteric marginal (Griffith point) and inferior phrenic arteries by using 5-point visual scoring systems. Kappa analysis was used for evaluation of interobserver agreement. To compare the visualization capability of the two systems, the Mann-Whitney U-test was used to compare the scores for each of the arteries. Results: Overall interobserver agreements for both systems were almost perfect (κ > 0.80). Visualization scores for inferior epigastric and mesenteric arteries were significantly higher for ADCT than for 64-detector row CT (p < 0.05). No significant difference was found for hepatic subsegmental and inferior phrenic arteries. Conclusion: Small abdominal vasculature assessment by ADCT with step-and-shoot scan protocol is potentially equal to or better than that by 64-detector row CT with helical scan protocol.

  9. Multi-Detector CT Findings of the Normal Appendix in Children: Evaluation of the Position, Diameter, and Presence or Absence of Intraluminal Gas

    Energy Technology Data Exchange (ETDEWEB)

    Park, Woon Ju; Kim, Jong Chul [Dept. of Radiology, Chungnam National University College of Medicine, Daejeon (Korea, Republic of)

    2011-08-15

    To assess the usefulness of multi-detector CT (MDCT) with multiplanar reformations (MPR) for the evaluation of the position, diameter and presence or absence of intraluminal gas in the normal appendix in children. From 2007 to 2010, we retrospectively analyzed the MDCT images of normal appendices in 133 children, and evaluated the position, diameter, and presence or absence of intraluminal gas in the appendix. Among the 133 appendices, type I (postileal and medial paracecal position) was found in 64 children, type II (subcecal position) in 22, type III (retrocecal and retrocolic/laterocolic position) in 15, type IV (preileal and medial colic position) in 16, and type V (lower pelvic position) in 16 children. The mean diameter was 5.8 mm {+-} 1.2 (SD) (range; 3.2-8.7 mm). There was a high correlation between the appendiceal diameter and age (p = 0.000).There was no statistically significant difference in the appendiceal diameter between boys and girls (p = 0.470). Intraluminal gas was found in 115 appendices and there was no statistically significant correlation between the appendiceal diameter and intraluminal gas (p = 0.502). The MDCT with MPR was useful for the evaluation of the normal appendices in children. The procedure may be useful for the diagnosis of equivocal or unusual appendicitis in children.

  10. Contribution of multi-detector row CT (MDCT) to decision making in the management of patients with small bowel obstruction or ileus

    International Nuclear Information System (INIS)

    Osada, Hisato; Watanabe, Wataru; Okada, Taketomo

    2007-01-01

    We retrospectively evaluated the contribution of multi-detector row CT (MDCT) to patient management decisions in 62 patients with small bowel obstruction or ileus. The sensitivity and specificity of MDCT diagnosis of small bowel obstruction with strangulation or closed loop were 78.9% (15/19) and 93.0% (40/43), respectively. In 19 patients with small bowel obstruction with strangulation or closed loop, the median interval between CT examination and the commencement of surgery was significantly longer in misdiagnosed patients than in those correctly diagnosed (43.3 vs. 4.5 hours, p<0.05). Only two patients displayed severe physical signs that required urgent surgical treatment. Our results suggest that MDCT plays a key role in the management of patients with small bowel obstruction. (author)

  11. Modelling the Siemens SOMATOM Sensation 64 Multi-Slice CT (MSCT) Scanner

    International Nuclear Information System (INIS)

    Amin, A T Mohd; Rahni, A A Abd

    2017-01-01

    Reconstructing large volumetric 3D images with minimal radiation dosage exposure with reduced scanning time has been one of the main objectives in the advancement of CT development. One of its advancement is the introduction of multi-slice arc detector geometry from a cone-beam source in third generation scanners. In solving this complex geometry, apart from the known vast computations in CT image reconstruction due to large CT images, iterative reconstruction methods are preferred compared to analytic methods due to its flexibility in image reconstruction. A scanner of interest that has this type of geometry is the Siemens SOMATOM Sensation 64 Multi-Slice CT (MSCT) Scanner , which has a total of 32 slices with 672 detector elements on each slice. In this paper, the scanner projection is modelled via the intersecting lengths between each ray (exhibited from the source to the detector elements) with the scanned image voxels, which are evaluated using the classical Siddon’s algorithm to generate the system matrix, H . This is a prerequisite to perform various iterative reconstruction methods, which involves solving the inverse problem arising from the linear equation: S = H· I; where S is the projections produced from the image, I. Due to the ‘cone-beam geometry’ along the z -axis, the effective field-of-view (FOV) with voxel dimensions (0.4×0.4×0.4) mm 3 is 512×512×32 voxels. The scanner model is demonstrated by reconstructing an image from simulated projections using the analytic Feldkamp-Davis-Kress (FDK) method against basic iterative image reconstruction methods. (paper)

  12. Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography.

    Science.gov (United States)

    Caro-Domínguez, Pablo; Compton, Gregory; Humpl, Tilman; Manson, David E

    2016-09-01

    The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children. To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children. We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension. Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension. The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children.

  13. Evaluation of the effective dose and image quality of low-dose multi-detector CT for orthodontic treatment planning

    International Nuclear Information System (INIS)

    Chung, Gi Chung; Han, Won Jeong; Kim, Eun Kyung

    2010-01-01

    This study was designed to compare the effective doses from low-dose and standard-dose multi-detector CT (MDCT) scanning protocols and evaluate the image quality and the spatial resolution of the low-dose MDCT protocols for clinical use. 6-channel MDCT scanner (Siemens Medical System, Forschheim, Germany), was used for this study. Protocol of the standard-dose MDCT for the orthodontic analysis was 130 kV, 35 mAs, 1.25 mm slice width, 0.8 pitch. Those of the low-dose MDCT for orthodontic analysis and orthodontic surgery were 110 kV, 30 mAs, 1.25 mm slice width, 0.85 pitch and 110 kV, 45 mAs, 2.5 mm slice width, 0.85 pitch. Thermoluminescent dosimeters (TLDs) were placed at 31 sites throughout the levels of adult female ART head and neck phantom. Effective doses were calculated according to ICRP 1990 and 2007 recommendations. A formalin-fixed cadaver and AAPM CT performance phantom were scanned for the evaluation of subjective image quality and spatial resolution. Effective doses in μSv (E2007) were 699.1, 429.4 and 603.1 for standard-dose CT of orthodontic treatment, low-dose CT of orthodontic analysis, and low-dose CT of orthodontic surgery, respectively. The image quality from the low-dose protocol were not worse than those from the standard-dose protocol. The spatial resolutions of both standard-dose and low-dose CT images were acceptable. From the above results, it can be concluded that the low-dose MDCT protocol is preferable in obtaining CT images for orthodontic analysis and orthodontic surgery.

  14. Evaluation of the effective dose and image quality of low-dose multi-detector CT for orthodontic treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Gi Chung; Han, Won Jeong; Kim, Eun Kyung [Department of Oral and Maxillofacial Radiology, School of Dentistry, Dankook University, Cheonan (Korea, Republic of)

    2010-03-15

    This study was designed to compare the effective doses from low-dose and standard-dose multi-detector CT (MDCT) scanning protocols and evaluate the image quality and the spatial resolution of the low-dose MDCT protocols for clinical use. 6-channel MDCT scanner (Siemens Medical System, Forschheim, Germany), was used for this study. Protocol of the standard-dose MDCT for the orthodontic analysis was 130 kV, 35 mAs, 1.25 mm slice width, 0.8 pitch. Those of the low-dose MDCT for orthodontic analysis and orthodontic surgery were 110 kV, 30 mAs, 1.25 mm slice width, 0.85 pitch and 110 kV, 45 mAs, 2.5 mm slice width, 0.85 pitch. Thermoluminescent dosimeters (TLDs) were placed at 31 sites throughout the levels of adult female ART head and neck phantom. Effective doses were calculated according to ICRP 1990 and 2007 recommendations. A formalin-fixed cadaver and AAPM CT performance phantom were scanned for the evaluation of subjective image quality and spatial resolution. Effective doses in {mu}Sv (E2007) were 699.1, 429.4 and 603.1 for standard-dose CT of orthodontic treatment, low-dose CT of orthodontic analysis, and low-dose CT of orthodontic surgery, respectively. The image quality from the low-dose protocol were not worse than those from the standard-dose protocol. The spatial resolutions of both standard-dose and low-dose CT images were acceptable. From the above results, it can be concluded that the low-dose MDCT protocol is preferable in obtaining CT images for orthodontic analysis and orthodontic surgery.

  15. Reducing image noise in computed tomography (CT) colonography: effect of an integrated circuit CT detector.

    Science.gov (United States)

    Liu, Yu; Leng, Shuai; Michalak, Gregory J; Vrieze, Thomas J; Duan, Xinhui; Qu, Mingliang; Shiung, Maria M; McCollough, Cynthia H; Fletcher, Joel G

    2014-01-01

    To investigate whether the integrated circuit (IC) detector results in reduced noise in computed tomography (CT) colonography (CTC). Three hundred sixty-six consecutive patients underwent clinically indicated CTC using the same CT scanner system, except for a difference in CT detectors (IC or conventional). Image noise, patient size, and scanner radiation output (volume CT dose index) were quantitatively compared between patient cohorts using each detector system, with separate comparisons for the abdomen and pelvis. For the abdomen and pelvis, despite significantly larger patient sizes in the IC detector cohort (both P 0.18). Based on the observed image noise reduction, radiation dose could alternatively be reduced by approximately 20% to result in similar levels of image noise. Computed tomography colonography images acquired using the IC detector had significantly lower noise than images acquired using the conventional detector. This noise reduction can permit further radiation dose reduction in CTC.

  16. Peliosis Hepatis with Hemorrhagic Necrosis and Rupture: a Case Report with Emphasis on the Multi-Detector CT Findings

    International Nuclear Information System (INIS)

    Kim, Eun-A; Yoon, Kwon-Ha; Jeon, Se-Jung; Cai, Quan-Yu; Lee, Young-Whan

    2007-01-01

    We demonstrate the imaging findings, with emphasis on the triphasic, contrast-enhanced multidetector CT findings, as well as reporting the clinical outcome in a case of peliosis hepatis with fatal hemorrhage. eliosis hepatis is an uncommon condition characterized by blood-filled cystic cavities in the liver. The clinical presentation is quite variable from an asymptomatic presentation to hepatic failure, portal hypertension or fatal intraabdominal hemorrhage. The exact incidence of intrahepatic or intraperitoneal hemorrhage by liver rupture has not been determined in the literature and these complications have been demonstrated only in the form of about 20 case reports. On angiography, peliosis hepatis can be suspected by multiple small contrast accumulations that become distinct during the parenchymal phase and are persistent during the venous phase. Examinations using multidetector CT (MDCT) scanners, which provide thin-section, contrast-enhanced dynamic images, are increasing nowadays. Thus, this entity has a better chance to be incidentally encountered and to be a diagnostic challenge to the radiologists. In this report, we present a case of peliosis hepatis with hemorrhagic necrosis that was complicated by massive intrahepatic bleeding and rupture. We demonstrate the imaging findings with emphasis on the contrast-enhanced dynamic MDCT features as well as the clinical outcome after treatment

  17. Peliosis Hepatis with Hemorrhagic Necrosis and Rupture: a Case Report with Emphasis on the Multi-Detector CT Findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun-A; Yoon, Kwon-Ha; Jeon, Se-Jung; Cai, Quan-Yu; Lee, Young-Whan [Wonkwang University School of Medicine, Iksan (Korea, Republic of)

    2007-02-15

    We demonstrate the imaging findings, with emphasis on the triphasic, contrast-enhanced multidetector CT findings, as well as reporting the clinical outcome in a case of peliosis hepatis with fatal hemorrhage. eliosis hepatis is an uncommon condition characterized by blood-filled cystic cavities in the liver. The clinical presentation is quite variable from an asymptomatic presentation to hepatic failure, portal hypertension or fatal intraabdominal hemorrhage. The exact incidence of intrahepatic or intraperitoneal hemorrhage by liver rupture has not been determined in the literature and these complications have been demonstrated only in the form of about 20 case reports. On angiography, peliosis hepatis can be suspected by multiple small contrast accumulations that become distinct during the parenchymal phase and are persistent during the venous phase. Examinations using multidetector CT (MDCT) scanners, which provide thin-section, contrast-enhanced dynamic images, are increasing nowadays. Thus, this entity has a better chance to be incidentally encountered and to be a diagnostic challenge to the radiologists. In this report, we present a case of peliosis hepatis with hemorrhagic necrosis that was complicated by massive intrahepatic bleeding and rupture. We demonstrate the imaging findings with emphasis on the contrast-enhanced dynamic MDCT features as well as the clinical outcome after treatment.

  18. Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography

    International Nuclear Information System (INIS)

    Caro-Dominguez, Pablo; Manson, David E.; Compton, Gregory; Humpl, Tilman

    2016-01-01

    The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children. To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children. We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension. Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension. The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children. (orig.)

  19. Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Caro-Dominguez, Pablo; Manson, David E. [University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Department of Medical Imaging, Toronto, ON (Canada); Compton, Gregory [University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Department of Medical Imaging, Toronto, ON (Canada); Epworth Hospital, Epworth Medical Imaging, Richmond, VIC (Australia); Humpl, Tilman [University of Toronto, Division of Cardiology, Department of Pediatrics, The Hospital for Sick Children, Toronto, ON (Canada)

    2016-09-15

    The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children. To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children. We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension. Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension. The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children. (orig.)

  20. Multicenter Comparison of Contrast-Enhanced FDG PET/CT and 64-Slice Multi-Detector-Row CT for Initial Staging and Response Evaluation at the End of Treatment in Patients With Lymphoma.

    Science.gov (United States)

    Gómez León, Nieves; Delgado-Bolton, Roberto C; Del Campo Del Val, Lourdes; Cabezas, Beatriz; Arranz, Reyes; García, Marta; Cannata, Jimena; González Ortega, Saturnino; Pérez Sáez, Mª Ángeles; López-Botet, Begoña; Rodríguez-Vigil, Beatriz; Mateo, Marta; Colletti, Patrick M; Rubello, Domenico; Carreras, José L

    2017-08-01

    To compare staging correctness between contrast-enhanced FDG PET/ceCT and 64-slice multi-detector-row CT (ceCT64) for initial staging and response evaluation at the end of treatment (EOT) in patients with Hodgkin lymphoma, diffuse large B cell lymphoma (DLBCL), and follicular lymphoma. This prospective study compared initial staging and response evaluation at EOT. One hundred eighty-one patients were randomly assigned to either ceCT64 or FDG PET/ceCT. A nuclear medicine physician and a radiologist read FDG PET/ceCT scans independently and achieved post hoc consensus, whereas another independent radiologist interpreted ceCT64 separately. The reference standard included all clinical information, all tests, and follow-up. Ethics committees of the participating centers approved the study, and all participants provided written consent. Ninety-one patients were randomized to ceCT64 and 90 to FDG PET/ceCT; 72 had Hodgkin lymphoma, 72 had DLBCL, and 37 had follicular lymphoma. There was excellent correlation between the reference standard and initial staging for both FDG PET/ceCT (κ = 0.96) and ceCT64 (κ = 0.84), although evaluation of the response at EOT was excellent only for FDG PET/ceCT (κ = 0.91). Our study demonstrated satisfactory agreement between FDG PET/ceCT (κ = 0.96) and ceCT64 (κ = 0.84) in initial staging compared with the reference standard (P = 0.16). Response evaluation at EOT with FDG PET/ceCT (κ = 0.91) was superior compared with ceCT64 (κ = 0.307) (P < 0.001).

  1. Computer-assisted lung nodule volumetry from multi-detector row CT: Influence of image reconstruction parameters

    International Nuclear Information System (INIS)

    Honda, Osamu; Sumikawa, Hiromitsu; Johkoh, Takeshi; Tomiyama, Noriyuki; Mihara, Naoki; Inoue, Atsuo; Tsubamoto, Mitsuko; Natsag, Javzandulam; Hamada, Seiki; Nakamura, Hironobu

    2007-01-01

    Purpose: To investigate differences in volumetric measurement of pulmonary nodules caused by changing the reconstruction parameters for multi-detector row CT. Materials and methods: Thirty-nine pulmonary nodules less than 2 cm in diameter were examined by multi-slice CT. All nodules were solid, and located in the peripheral part of the lungs. The resultant 48 parameters images were reconstructed by changing slice thickness (1.25, 2.5, 3.75, or 5 mm), field of view (FOV: 10, 20, or 30 cm), algorithm (high-spatial frequency algorithm or low-spatial frequency algorithm) and reconstruction interval (reconstruction with 50% overlapping of the reconstructed slices or non-overlapping reconstruction). Volumetric measurements were calculated using commercially available software. The differences between nodule volumes were analyzed by the Kruskal-Wallis test and the Wilcoxon Signed-Ranks test. Results: The diameter of the nodules was 8.7 ± 2.7 mm on average, ranging from 4.3 to 16.4 mm. Pulmonary nodule volume did not change significantly with changes in slice thickness or FOV (p > 0.05), but was significantly larger with the high-spatial frequency algorithm than the low-spatial frequency algorithm (p < 0.05), except for one reconstruction parameter. The volumes determined by non-overlapping reconstruction were significantly larger than those of overlapping reconstruction (p < 0.05), except for a 1.25 mm thickness with 10 cm FOV with the high-spatial frequency algorithm, and 5 mm thickness. The maximum difference in measured volume was 16% on average between the 1.25 mm slice thickness/10 cm FOV/high-spatial frequency algorithm parameters and overlapping reconstruction. Conclusion: Volumetric measurements of pulmonary nodules differ with changes in the reconstruction parameters, with a tendency toward larger volumes in high-spatial frequency algorithm and non-overlapping reconstruction compared to the low-spatial frequency algorithm and overlapping reconstruction

  2. Comparison of radiation dose estimates, image noise, and scan duration in pediatric body imaging for volumetric and helical modes on 320-detector CT and helical mode on 64-detector CT

    International Nuclear Information System (INIS)

    Johnston, Jennifer H.; Podberesky, Daniel J.; Larson, David B.; Alsip, Christopher; Yoshizumi, Terry T.; Angel, Erin; Barelli, Alessandra; Toncheva, Greta; Egelhoff, John C.; Anderson-Evans, Colin; Nguyen, Giao B.; Frush, Donald P.; Salisbury, Shelia R.

    2013-01-01

    Advanced multidetector CT systems facilitate volumetric image acquisition, which offers theoretic dose savings over helical acquisition with shorter scan times. Compare effective dose (ED), scan duration and image noise using 320- and 64-detector CT scanners in various acquisition modes for clinical chest, abdomen and pelvis protocols. ED and scan durations were determined for 64-detector helical, 160-detector helical and volume modes under chest, abdomen and pelvis protocols on 320-detector CT with adaptive collimation and 64-detector helical mode on 64-detector CT without adaptive collimation in a phantom representing a 5-year-old child. Noise was measured as standard deviation of Hounsfield units. Compared to 64-detector helical CT, all acquisition modes on 320-detector CT resulted in lower ED and scan durations. Dose savings were greater for chest (27-46%) than abdomen/pelvis (18-28%) and chest/abdomen/pelvis imaging (8-14%). Noise was similar across scanning modes, although some protocols on 320-detector CT produced slightly higher noise. Dose savings can be achieved for chest, abdomen/pelvis and chest/abdomen/pelvis examinations on 320-detector CT compared to helical acquisition on 64-detector CT, with shorter scan durations. Although noise differences between some modes reached statistical significance, this is of doubtful diagnostic significance and will be studied further in a clinical setting. (orig.)

  3. Flat-detector computed tomography (FD-CT)

    International Nuclear Information System (INIS)

    Kalender, Willi A.; Kyriakou, Yiannis

    2007-01-01

    Flat-panel detectors or, synonymously, flat detectors (FDs) have been developed for use in radiography and fluoroscopy with the defined goal to replace standard X-ray film, film-screen combinations and image intensifiers by an advanced sensor system. FD technology in comparison to X-ray film and image intensifiers offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. Respective efforts date back a few years only, but FD-CT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. FD-CT provides a very efficient way of combining two-dimensional (2D) radiographic or fluoroscopic and 3D CT imaging. In addition, FD technology made its way into a number of dedicated CT scanner developments, such as scanners for the maxillo-facial region or for micro-CT applications. This review focuses on technical and performance issues of FD technology and its full range of applications for CT imaging. A comparison with standard clinical CT is of primary interest. It reveals that FD-CT provides higher spatial resolution, but encompasses a number of disadvantages, such as lower dose efficiency, smaller field of view and lower temporal resolution. FD-CT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations; but it has already proven unique for a number of dedicated CT applications, offering distinct practical advantages, above all the availability of immediate CT imaging in the interventional suite or the operating room. (orig.)

  4. Multi-detector row CT in the assessment of axillary lymph node metastasis in breast cancer

    International Nuclear Information System (INIS)

    Murakami, Shogo

    2003-01-01

    The purpose of this study is to evaluate the diagnostic capability instead of clinical efficacy of multi-detector row CT (MDCT) in the assessment of axillary lymph node metastasis in breast cancer. MDCT was performed in 63 patients with breast cancer, and multiplanar reformation (MPR) and volume rendering (VR) images were reconstructed for the evaluation of bilateral axillary lymph nodes. Two hundred sixty eight lymph nodes were depicted with MDCT, and correlation with pathological findings was performed. The short axis length of lymph node was measured on MPR image, and the shape of the nodes was analyzed with the pathological results statistically. The diagnostic criteria on size and shape of lymph node metastasis were discussed Dynamic study with contrast media was also performed, and the CT value ratios (CTVR) of the lymph nodes and breast tumors were calculated. No relevance of axillary lymph node metastasis was noted to the pathological types of breast cancer. The average short axis length of the ipsilateral axillary nodes was 8.9 mm±3.8 (SD) while that of the contralateral nodes was 4.9 mm±1.1 (SD) showing significant difference. More than 6.5 mm in short length of the lymph node was thought to be an effective criterion for positive metastasis, and its sensitivity was 96%. Soybean-shape lymph node was statistically common in metastasis, while non-metastatic nodes were commonly demonstrated as letter ''c'' shape or ring-like shape. Statistical relevance was obtained between the CTVR of axillary lymph nodes and that of breast tumors, suggesting clinical usefulness of dynamic study using contrast media in the evaluation of lymph node metastasis. With MPR and VR images using MDCT, more accurate morphological evaluation of axillary lymph nodes was possible. When soybean-shape node with more than 6.5 mm in short axis is depicted in the axillar region on MDCT metastasis should be the consideration. Comparison with the contralateral side as a control in coronal

  5. Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, N.G. [University of Otago, Department of Radiology, Christchurch (New Zealand); Butler, A.P. [University of Otago, Department of Radiology, Christchurch (New Zealand); University of Canterbury, Physics and Astronomy, Christchurch (New Zealand); Scott, N.J.A. [University of Otago, Department of Medicine, Christchurch (New Zealand); Cook, N.J. [Christchurch Hospital, Medical Physics and Bioengineering, Christchurch (New Zealand); Butzer, J.S. [Karlsruhe Institute of Technology, Physics Department, Karlsruhe (Germany); Schleich, N. [University of Canterbury, Physics and Astronomy, Christchurch (New Zealand); Christchurch Hospital, Medical Physics and Bioengineering, Christchurch (New Zealand); Firsching, M. [Friedrich Alexander University, Physics Department, Erlangen (Germany); Grasset, R.; Ruiter, N. de [University of Canterbury, Hitlab NZ, Christchurch (New Zealand); Campbell, M. [European Organisation for Nuclear Research, Physics Section, Geneva (Switzerland); Butler, P.H. [University of Canterbury, Physics and Astronomy, Christchurch (New Zealand)

    2010-09-15

    Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 {mu}A). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct from soft tissue and bone in all six mice. Calcium, iodine and barium were displayed as separate channels on 3D colour images at <55 {mu}m isotropic voxels. Spectral CT distinguishes contrast agents with K-edges only 4 keV apart. Multi-contrast imaging and molecular CT are potential future applications. (orig.)

  6. Comparison of a dental cone beam CT with a multi-detector row CT on effective doses and physical image quality

    International Nuclear Information System (INIS)

    Yoshida, Yutaka; Tokumori, Kenji; Okamura, Kazutoshi; Yoshiura, Kazunori

    2011-01-01

    The purpose of this study was to compare a dental cone beam computed tomography (dental CBCT) and a multi-detector row CT (MDCT) using effective doses and physical image quality. A dental mode (D-mode) and an implant mode (I-mode) were employed for calculating effective doses. Field of view (FOV) size of the MDCT was 150 mm. Three types of images were obtained using 3 different reconstruction functions: FC1 (for abdomen images), FC30 (for internal ear and bone images) and FC81 (for high resolution images). Effective doses obtained with the D-mode and with the I-mode were about 20% and 50% of those obtained with the MDCT, respectively. Resolution properties obtained with the D-mode and I-mode were superior to that of the MDCT in a high frequency range. Noise properties of the D-mode and the I-mode were better than those with FC81. It was found that the dental CBCT has better potential as compared with MDCT in both dental and implant modes. (author)

  7. Interesting detector shapes for 3rd generation CT

    Energy Technology Data Exchange (ETDEWEB)

    Kachelriess, Marc [Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. of Medical Physics (IMP)

    2011-07-01

    Third generation CT scanners typically comprise detectors which are flat or whose shape is the segment of a cylinder or a sphere that is focussed onto the focal spot of the X-ray source. There appear to be two design criteria that favor this choice of detector shape. One is the possibility of performing fan-beam and cone-beam filtered backprojection in the native geometry (without rebinning) and the other criterium is to enable the use of focussed anti scatter grids. It is less known, however, that other detector shapes may also have these properties. While these designs have been evaluated for 2D CT from a rather theoretical standpoint more than one decade ago we revisit and generalize these considerations, extend them to 3D circular, sequential and spiral cone-beam CT and propose an optimal design in terms of detector costs. (orig.)

  8. First experience of combined cardiac PET/64-detector CT angiography with invasive angiographic validation

    International Nuclear Information System (INIS)

    Groves, Ashley M.; Kayani, Irfan; Endozo, Raymondo; Menezes, Leon J.; Prvulovich, Elizabeth; Ell, Peter J.; Speechly-Dick, Marie-Elsya; McEwan, Jean; Pugliese, Francesca; Habib, Said B.

    2009-01-01

    Despite modern CT systems and expert evaluators, the diagnostic performance of coronary CT angiography is limited by overestimation of vessel stenosis which reduces the positive predictive value (PPV) of the test. The aim of this study was to evaluate the performance of combined cardiac PET/64-detector CT angiography. Included in this retrospective study were 33 consecutive patients (5 women, 28 men; mean age 61.6 years, range 47-87 years, mean BMI 27.3±5.2 kg/m 2 ) with clinically suspected flow-limiting coronary artery disease who underwent combined cardiac PET/64-detector CT angiography and invasive angiography. Combined PET/CT images were reported by an experienced dual-accredited radiologist/nuclear physician. An experienced cardiac CT radiologist re-read the CT images without PET. Stenotic disease was defined as >50% vessel narrowing. Invasive coronary angiography was used as a reference standard. Local ethics committee approval and patient consent were obtained. CT angiography (without PET data) was concordant with invasive angiography in 31/33 patients and at a patient level, the sensitivity in detecting significant coronary artery lesions was 100%, the specificity was 82%, the PPV was 92% and the negative predictive value (NPV) was 100%. Using combined PET/CT angiography the findings were concordant with invasive angiography in 32/33 patients and at a patient level, the sensitivity was 96%, the specificity was 100%, the PPV was 100% and the NPV was 91%. The use of integrated cardiac PET/64-detector CT angiography is feasible and appears to improve some aspects of the diagnostic performance of 64-detector coronary artery angiography in detecting coronary artery disease. (orig.)

  9. Normal mediastinal and hilar lymph nodes in children on multi-detector row chest computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Jong, Pim A. de; Nievelstein, Rutger-Jan A. [University Medical Center Utrecht and Wilhelmina Children' s Hospital, Department of Radiology, Utrecht (Netherlands)

    2012-02-15

    To study normal mediastinal and hilar lymph nodes on multi-detector chest computed tomography (CT). A cohort of 120 children aged 1-17 years underwent emergency CT, including the chest, after high-energy trauma. Axial 5-mm reconstructions were evaluated for lymph nodes at hilar and various mediastinal levels and the short-axis diameters were measured. At least one lymph node was found in 115 (96%) children, with subcarinal (69%), lower paratracheal (64%) and hilar (60%) nodes being most common. Up to 10 years of age most lymph nodes were smaller than or equal to 7 mm. In older children lymph nodes measuring up to 10-mm-short-axis diameter were found. Lymph nodes were rare along the mammary vessels, at lower oesophageal and at prevascular and posterior mediastinal levels in children. Mediastinal and hilar lymph nodes are more common than previously thought, probably because of increased detection by modern multi-detector CT. Lymph node location and age have to be taken into account when evaluating lymph nodes in the paediatric chest. (orig.)

  10. Normal mediastinal and hilar lymph nodes in children on multi-detector row chest computed tomography

    International Nuclear Information System (INIS)

    Jong, Pim A. de; Nievelstein, Rutger-Jan A.

    2012-01-01

    To study normal mediastinal and hilar lymph nodes on multi-detector chest computed tomography (CT). A cohort of 120 children aged 1-17 years underwent emergency CT, including the chest, after high-energy trauma. Axial 5-mm reconstructions were evaluated for lymph nodes at hilar and various mediastinal levels and the short-axis diameters were measured. At least one lymph node was found in 115 (96%) children, with subcarinal (69%), lower paratracheal (64%) and hilar (60%) nodes being most common. Up to 10 years of age most lymph nodes were smaller than or equal to 7 mm. In older children lymph nodes measuring up to 10-mm-short-axis diameter were found. Lymph nodes were rare along the mammary vessels, at lower oesophageal and at prevascular and posterior mediastinal levels in children. Mediastinal and hilar lymph nodes are more common than previously thought, probably because of increased detection by modern multi-detector CT. Lymph node location and age have to be taken into account when evaluating lymph nodes in the paediatric chest. (orig.)

  11. Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE.

    Science.gov (United States)

    Anderson, N G; Butler, A P; Scott, N J A; Cook, N J; Butzer, J S; Schleich, N; Firsching, M; Grasset, R; de Ruiter, N; Campbell, M; Butler, P H

    2010-09-01

    Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 microA). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct from soft tissue and bone in all six mice. Calcium, iodine and barium were displayed as separate channels on 3D colour images at contrast agents with K-edges only 4 keV apart. Multi-contrast imaging and molecular CT are potential future applications.

  12. Basic examination of in-plane spatial resolution in multi-slice CT

    International Nuclear Information System (INIS)

    Hara, Takanori; Kato, Hideki; Akiyama, Mitsutoshi; Murata, Katsutoshi

    2002-01-01

    In computed tomography (single-slice spiral CT, conventional CT), in-plane (x-y plane) spatial resolution is consistently identified as depending on the detector density of the in-plane (x-y plane). However, we considered that the in-plane (x-y plane) spatial resolution of multi-slice CT (MSCT) was influenced by an error in the detector's sensitivity to the Z-axis and by the frequency of use of direct row data and complementary row data when the image of spiral pitches (SP) was reconstructed. Our goal in this experiment was to analyze the relationship of the in-plane (x-y plane) spatial resolution of an asymmetric-type detector in MSCT to SP, tube current, and rotation time. By employing a tungsten wire phantom of 0.2 mm in diameter, we examined modulation transfer functions (MTF) by point-spread functions (PSF) of CT-images. Next, using the mean-square-root bandwidth theory, we analyzed the MTF of wire phantoms. The analysis of in-plane (x-y plane) spatial resolution revealed that various tube currents had no effect on the value of the mean-square-root bandwidth. However, rotation time and high spiral pitch did have an effect on mean-square-root bandwidth. Considering the results mentioned above, spiral pitch (z-axis reconstruction algorithm) had a slight effect on in-plane (x-y plane) spatial resolution of asymmetric-type detectors in MSCT. Accordingly, we proposed a new general view of VDDz (view/mm) in MSCT that considered view data density on the Z-axis according to spiral pitch (mm/rotation), rotation time (view/rotation), and slice collimation. (author)

  13. A new timing detector for the CT-PPS project

    Energy Technology Data Exchange (ETDEWEB)

    Arcidiacono, R. [INFN – Torino (Italy); Università del Piemonte Orientale (Italy)

    2017-02-11

    The CT-PPS detector will be installed close to the beam line on both sides of CMS, 200 m downstream the interaction point. This detector will measure forward scattered protons, allowing detailed studies of diffractive hadron physics and Central Exclusive Production. The main components of the CT-PPS detector are a silicon tracking system and a timing system. In this contribution we present the proposal of an innovative solution for the timing system, based on Ultra-Fast Silicon Detectors (UFSD). UFSD are a novel concept of silicon detectors potentially able to obtain the necessary time resolution (∼20 ps on the proton arrival time). The use of UFSD has also other attractive features as its material budget is small and the pixel geometries can be tailored to the precise physics distribution of protons. UFSD prototypes for CT-PPS have been designed by CNM (Barcelona) and FBK (Trento): we will present the status of the sensor productions and of the low-noise front-end electronics currently under development and test.

  14. Data explosion: the challenge of multidetector-row CT

    International Nuclear Information System (INIS)

    Rubin, Geoffrey D.

    2000-01-01

    The development of multi detector-row CT has brought many exciting advancements to clinical CT scanning. While multi detector-row CT offers unparalleled speed of acquisition, spatial resolution, and anatomic coverage, a challenge presented by these advantages is the substantial increase on the number of reconstructed cross-sections that are rapidly created and in need of analysis. This manuscript discusses currently available alternative visualization techniques for the assessment of volumetric data acquired with multi detector-row CT. Although the current capabilities of 3-D workstations offer many possibilities for alternative analysis of MCDT data, substantial improvements both in automated processing, processing speed and user interface will be necessary to realize the vision of replacing the primary analysis of transverse reconstruction's with alternative analyses. The direction that some of these future developments might take are discussed

  15. A anatomic evaluation of the lateral femoral circumflex artery system by using Multi detector-row CT

    International Nuclear Information System (INIS)

    Haraguchi, Kazunari; Kadota, Satoshi; Hosaka, Yoshiaki

    2010-01-01

    Flaps that are pedicled by perforators of the lateral femoral circumflex artery (LFCA) system have many advantages, including the transplantation of large and reliable skin with long pedicles and a large diameter, and little invasion of the donor sites. However, preoperative planning has been difficult because the perforators have many anatomic variations. We used multi detector-row CT for anatomical evaluation of the lateral femoral circumflex artery system. The patterns of LFCA from the main vessels were classified into three types and vessels coursing toward the lateral thigh region were classified into three groups. The distance from the anterior superior iliac spine to the lateral femoral circumflex artery showed no significant difference between men and women. We were able to evaluate vessels with a 2-mm diameter in the lateral femoral circumflex artery system, indicating that accurate evaluation and low invasive examination of the lateral femoral circumflex artery system, including the perforator area, can be achieved by adjusting the image conditions and the injection rate of the contrast dye. (author)

  16. Flat-detector computed tomography in the assessment of intracranial stents: comparison with multi detector CT and conventional angiography in a new animal model

    International Nuclear Information System (INIS)

    Struffert, Tobias; Ott, Sabine; Adamek, Edyta; Schwarz, Marc; Engelhorn, Tobias; Kloska, Stephan; Doerfler, Arnd; Deuerling-Zheng, Yu

    2011-01-01

    Careful follow up is necessary after intracranial stenting because in-stent restenosis (ISR) or residual stenosis (RS) is not rare. A minimally invasive follow-up imaging technique is desirable. The objective was to compare the visualisation of stents in Flat Detector-CT Angiography (FD-CTA) after intravenous contrast medium injection (i.v.) with Multi Detector Computed Tomography Angiography (MD-CTA) and Digital Subtracted Angiography (DSA) in an animal model. Stents were implanted in the carotid artery of 12 rabbits. In 6 a residual stenosis (RS) was surgically created. Imaging was performed using FD-CTA, MD-CTA and DSA. Measurements of the inner and outer diameter and cross-section area of the stents were performed. Stenosis grade was calculated. In subjective evaluation FD-CTA was superior to MD-CTA. FD-CTA was more accurate compared with DSA than MD-CTA. Cross-sectional area of the stent lumen was significantly larger (p < 0.05) in FD-CTA in comparison to MD-CTA. Accurate evaluation of stenosis was impossible in MD-CTA. There was no statistically significant difference in the stenosis grade of DSA and FD-CTA. Our results show that visualisation of stent and stenosis using intravenous FD-CTA compares favourably with DSA and may replace DSA in the follow-up of patients treated with intracranial stents. (orig.)

  17. CT findings of infant epilepsy

    International Nuclear Information System (INIS)

    Hojoh, Hiroatsu; Kataoka, Kenkichi; Nakagawa, Yoshihiro; Nakano, Shozo; Tomita, Yutaka.

    1982-01-01

    CT diagnosis of infantile epilepsy was evaluated. High incidence of abnormal CT findings in infantile spasms and Lennox-Gastaut syndrome was same as in other reports. Comparison between CT findings and neurological complications and that between CT findings and electroencephalogram findings revealed a stronger relationship existing in the former. This suggested that CT is more useful as a measure to detect underlying diseases which are due to organic change of the brain to cause epilepsy, rather than as that to disclose epileptic primary lesions of functional change. (Ueda, J.)

  18. Dual- and Multi-Energy CT: Principles, Technical Approaches, and Clinical Applications

    Science.gov (United States)

    Leng, Shuai; Yu, Lifeng; Fletcher, Joel G.

    2015-01-01

    In x-ray computed tomography (CT), materials having different elemental compositions can be represented by identical pixel values on a CT image (ie, CT numbers), depending on the mass density of the material. Thus, the differentiation and classification of different tissue types and contrast agents can be extremely challenging. In dual-energy CT, an additional attenuation measurement is obtained with a second x-ray spectrum (ie, a second “energy”), allowing the differentiation of multiple materials. Alternatively, this allows quantification of the mass density of two or three materials in a mixture with known elemental composition. Recent advances in the use of energy-resolving, photon-counting detectors for CT imaging suggest the ability to acquire data in multiple energy bins, which is expected to further improve the signal-to-noise ratio for material-specific imaging. In this review, the underlying motivation and physical principles of dual- or multi-energy CT are reviewed and each of the current technical approaches is described. In addition, current and evolving clinical applications are introduced. © RSNA, 2015 PMID:26302388

  19. Peritoneal mesothelioma: CT and MRI findings

    International Nuclear Information System (INIS)

    Puvaneswary, M.; Chen, S.; Proietto, T.

    2002-01-01

    Two patients with histologically proven diagnosis of peritoneal mesothelioma are presented. Both patients had CT scans of the abdomen. The second patient was also examined with MRI. Although imaging findings are striking, they are non-specific and diagnosing peritoneal mesothelioma in the absence of pleural calcification or pleural plaque on chest radiograph or CT is difficult. However, it is possible to suggest the correct diagnosis in a patient with the presence of non-calcified omental and peritoneal infiltration or masses without liver secondaries or lymphadenopathy. Magnetic resonance imaging with its multi-planar capabilities is a highly sensitive non-invasive modality in the evaluation of malignant peritoneal mesothelioma and can demonstrate the exact site and clarify whether the mass is arising from the peritoneal surface or within a visceral organ. Copyright (2002) Blackwell Science Pty Ltd

  20. Data explosion: the challenge of multidetector-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, Geoffrey D. E-mail: grubin@standford.edu

    2000-11-01

    The development of multi detector-row CT has brought many exciting advancements to clinical CT scanning. While multi detector-row CT offers unparalleled speed of acquisition, spatial resolution, and anatomic coverage, a challenge presented by these advantages is the substantial increase on the number of reconstructed cross-sections that are rapidly created and in need of analysis. This manuscript discusses currently available alternative visualization techniques for the assessment of volumetric data acquired with multi detector-row CT. Although the current capabilities of 3-D workstations offer many possibilities for alternative analysis of MCDT data, substantial improvements both in automated processing, processing speed and user interface will be necessary to realize the vision of replacing the primary analysis of transverse reconstruction's with alternative analyses. The direction that some of these future developments might take are discussed.

  1. Evaluation of a metal artifact reduction algorithm applied to post-interventional flat detector CT in comparison to pre-treatment CT in patients with acute subarachnoid haemorrhage

    International Nuclear Information System (INIS)

    Mennecke, Angelika; Svergun, Stanislav; Doerfler, Arnd; Struffert, Tobias; Scholz, Bernhard; Royalty, Kevin

    2017-01-01

    Metal artefacts can impair accurate diagnosis of haemorrhage using flat detector CT (FD-CT), especially after aneurysm coiling. Within this work we evaluate a prototype metal artefact reduction algorithm by comparison of the artefact-reduced and the non-artefact-reduced FD-CT images to pre-treatment FD-CT and multi-slice CT images. Twenty-five patients with acute aneurysmal subarachnoid haemorrhage (SAH) were selected retrospectively. FD-CT and multi-slice CT before endovascular treatment as well as FD-CT data sets after treatment were available for all patients. The algorithm was applied to post-treatment FD-CT. The effect of the algorithm was evaluated utilizing the pre-post concordance of a modified Fisher score, a subjective image quality assessment, the range of the Hounsfield units within three ROIs, and the pre-post slice-wise Pearson correlation. The pre-post concordance of the modified Fisher score, the subjective image quality, and the pre-post correlation of the ranges of the Hounsfield units were significantly higher for artefact-reduced than for non-artefact-reduced images. Within the metal-affected slices, the pre-post slice-wise Pearson correlation coefficient was higher for artefact-reduced than for non-artefact-reduced images. The overall diagnostic quality of the artefact-reduced images was improved and reached the level of the pre-interventional FD-CT images. The metal-unaffected parts of the image were not modified. (orig.)

  2. Evaluation of a metal artifact reduction algorithm applied to post-interventional flat detector CT in comparison to pre-treatment CT in patients with acute subarachnoid haemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Mennecke, Angelika; Svergun, Stanislav; Doerfler, Arnd; Struffert, Tobias [University of Erlangen-Nuremberg, Department of Neuroradiology, Erlangen (Germany); Scholz, Bernhard [Siemens Healthcare GmbH, Forchheim (Germany); Royalty, Kevin [Siemens Medical Solutions, USA, Inc., Hoffman Estates, IL (United States)

    2017-01-15

    Metal artefacts can impair accurate diagnosis of haemorrhage using flat detector CT (FD-CT), especially after aneurysm coiling. Within this work we evaluate a prototype metal artefact reduction algorithm by comparison of the artefact-reduced and the non-artefact-reduced FD-CT images to pre-treatment FD-CT and multi-slice CT images. Twenty-five patients with acute aneurysmal subarachnoid haemorrhage (SAH) were selected retrospectively. FD-CT and multi-slice CT before endovascular treatment as well as FD-CT data sets after treatment were available for all patients. The algorithm was applied to post-treatment FD-CT. The effect of the algorithm was evaluated utilizing the pre-post concordance of a modified Fisher score, a subjective image quality assessment, the range of the Hounsfield units within three ROIs, and the pre-post slice-wise Pearson correlation. The pre-post concordance of the modified Fisher score, the subjective image quality, and the pre-post correlation of the ranges of the Hounsfield units were significantly higher for artefact-reduced than for non-artefact-reduced images. Within the metal-affected slices, the pre-post slice-wise Pearson correlation coefficient was higher for artefact-reduced than for non-artefact-reduced images. The overall diagnostic quality of the artefact-reduced images was improved and reached the level of the pre-interventional FD-CT images. The metal-unaffected parts of the image were not modified. (orig.)

  3. Evaluation of peripheral artery stent with 64-slice multi-detector row CT angiography: Prospective comparison with digital subtraction angiography

    International Nuclear Information System (INIS)

    Li Xiaoming; Li Yuhua; Tian Jianming; Xiao Yi; Lu Jianping; Jing Zaiping; Sheng Jing; Edwin, Angela; Wu Fanghong

    2010-01-01

    Purpose: To assess the accuracy of 64-slice multi-detector row computed tomography (MDCT) angiography in the evaluation of peripheral artery in-stent or peristent restenosis, with conventional digital subtraction angiography (DSA) as the reference standard. Materials and methods: Forty-one patients (30 men, 11 women; mean age, 69.8 ± 9.2 years) with symptomatic peripheral arterial occlusive disease after peripheral artery stenting (81 stented lesions) underwent both conventional DSA and 64-slice MDCT angiography. Each stent was classified as evaluable or unevaluable, and every stent was divided into three segments (proximal stent, stent body, and distal stent), resulting in 243 segments. For evaluation, stenosis was graded as follows: 1, none or slight stenosis (<25%); 2, mild stenosis (25-49%); 3, moderate stenosis (50-74%); 4, severe stenosis or total occlusion (≥75%). Two readers evaluated all CT angiograms with regard to narrowing of in-stent or peristent restenosis by consensus. Results were compared with findings of the DSA. Results: Of 81 stents, 62 (76.5%) were determined to be assessable. The metal artifact of the gold marker and motion artifact increased uninterpretability of the images of stents. Overall, 24 of 28 in-stent restenosis and 38 of 53 persistent restenosis were correctly detected by MDCT (85.7% and 71.7% sensitivity). In evaluable stents, 21 of 22 in-stent restenoses and 27 of 28 persistent restenosis were correctly detected (95.4% and 96.4% sensitivity). Additionally, as the grade of stenosis increases, the mean level of CT values in the stent lumina decreases linearly accordingly. Conclusion: 64-Slice MDCT has a high accuracy for the detection of significant in-stent or peristent restenosis of assessable stents in patients with peripheral artery stent implantation and therefore can be considered as a valuable noninvasive technique for stent surveillance.

  4. Evaluation of the retrospective ECG-gated helical scan using half-second multi-slice CT. Motion phantom study for volumetry

    International Nuclear Information System (INIS)

    Yamamoto, Shuji; Matsumoto, Takashi; Nakanishi, Shohzoh; Hamada, Seiki; Takahei, Kazunari; Naito, Hiroaki; Ogata, Yuji

    2002-01-01

    ECG synchronized technique on multi-slice CT provide the thinner (less 2 mm slice thickness) and faster (0.5 sec/rotation) scan than that of the single detector CT and can acquire the coverage of the entire heart volume within one breath-hold. However, temporal resolution of multi-slice CT is insufficient on practical range of heart rate. The purpose of this study was to evaluate the accuracy of volumetry on cardiac function measurement in retrospective ECG-gated helical scan. We discussed the influence of the degradation of image quality and limitation of the heart rate in cardiac function measurement (volumetry) using motion phantom. (author)

  5. Electronic noise in CT detectors: Impact on image noise and artifacts.

    Science.gov (United States)

    Duan, Xinhui; Wang, Jia; Leng, Shuai; Schmidt, Bernhard; Allmendinger, Thomas; Grant, Katharine; Flohr, Thomas; McCollough, Cynthia H

    2013-10-01

    The objective of our study was to evaluate in phantoms the differences in CT image noise and artifact level between two types of commercial CT detectors: one with distributed electronics (conventional) and one with integrated electronics intended to decrease system electronic noise. Cylindric water phantoms of 20, 30, and 40 cm in diameter were scanned using two CT scanners, one equipped with integrated detector electronics and one with distributed detector electronics. All other scanning parameters were identical. Scans were acquired at four tube potentials and 10 tube currents. Semianthropomorphic phantoms were scanned to mimic the shoulder and abdominal regions. Images of two patients were also selected to show the clinical values of the integrated detector. Reduction of image noise with the integrated detector depended on phantom size, tube potential, and tube current. Scans that had low detected signal had the greatest reductions in noise, up to 40% for a 30-cm phantom scanned using 80 kV. This noise reduction translated into up to 50% in dose reduction to achieve equivalent image noise. Streak artifacts through regions of high attenuation were reduced by up to 45% on scans obtained using the integrated detector. Patient images also showed superior image quality for the integrated detector. For the same applied radiation level, the use of integrated electronics in a CT detector showed a substantially reduced level of electronic noise, resulting in reductions in image noise and artifacts, compared with detectors having distributed electronics.

  6. The Road to the Common PET/CT Detector

    Science.gov (United States)

    Nassalski, Antoni; Moszynski, Marek; Szczesniak, Tomasz; Wolski, Dariusz; Batsch, Tadeusz

    2007-10-01

    Growing interest in the development of dual modality positron emission/X-rays tomography (PET/CT) systems prompts researchers to face a new challenge: to acquire both the anatomical and functional information in the same measurement, simultaneously using the same detection system and electronics. The aim of this work was to study a detector consisting of LaBr3, LSO or LYSO pixel crystals coupled to an avalanche photodiode (APD). The measurements covered tests of the detectors in PET and CT modes, respectively. The measurements included the determination of light output, energy resolution, the non-proportionality of the light yield and the time resolution for 511 keV annihilation quanta; analysis also included characterizing the PET detector, and determining the dependence of counting rate versus mean current of the APD in the X-ray detection. In the present experiment, the use of counting and current modes in the CT detection increases the dynamic range of the measured dose of X-rays by a factor of 20, compared to the counting mode alone.

  7. Multi-detector row helical CT of the liver. Quantitative assessment of iodine concentration of intravenous contrast material on multiphasic CT. A prospective randomized study

    International Nuclear Information System (INIS)

    Tsurusaki, Masakatsu; Sugimoto, Koji; Fujii, Masahiko; Sugimura, Kazuro

    2004-01-01

    The purpose of this study was to assess the quantitative effects of contrast material concentration on hepatic parenchymal and vascular enhancement in multiphasic computed tomography (CT), using multi-detector row helical CT. We designed a prospective randomized study to test two different concentrations of contrast material on five phasic scans of the liver. One hundred patients were randomly assigned to two groups: an iodine concentration of 300 mg/mL in group A and 370 mg/mL in group B. All patients received a fixed volume of 100 mL at a 4 mL/sec injection rate. Enhancement values for the hepatic parenchyma and aorta at three levels (upper, middle, and lower level of the liver), and values for portal and hepatic veins were statistically compared between the two groups. Hepatic parenchymal enhancement values at all levels of the liver in portal phase (PP) and equilibrium phase (EP) were significantly higher in group B than in group A (p<0.01). Aortic enhancement values at two levels of the liver (middle and lower) in early hepatic arterial phase (EAP) were significantly higher in group B than in group A (p<0.05), however, there was no significant difference between groups A and B in aortic enhancement during the delayed hepatic arterial phase (DAP). Portal and hepatic venous enhancement values in PP and EP were significantly higher in group B than in group A (p<0.01). On multiphasic dynamic CT, the use of a higher iodine concentration of contrast material results in higher hepatic parenchymal enhancement and aortic enhancement, as well as higher portal and hepatic venous enhancement. (author)

  8. Integrated circuit detector technology in abdominal CT: added value in obese patients.

    Science.gov (United States)

    Morsbach, Fabian; Bickelhaupt, Sebastian; Rätzer, Susan; Schmidt, Bernhard; Alkadhi, Hatem

    2014-02-01

    The purpose of this article was to assess the effect of an integrated circuit (IC) detector for abdominal CT on image quality. In the first study part, an abdominal phantom was scanned with various extension rings using a CT scanner equipped with a conventional discrete circuit (DC) detector and on the same scanner with an IC detector (120 kVp, 150 effective mAs, and 75 effective mAs). In the second study part, 20 patients were included who underwent abdominal CT both with the IC detector and previously at similar protocol parameters (120 kVp tube current-time product and 150 reference mAs using automated tube current modulation) with the DC detector. Images were reconstructed with filtered back projection. Image quality in the phantom was higher for images acquired with the IC compared with the DC detector. There was a gradually increasing noise reduction with increasing phantom sizes, with the highest (37% in the largest phantom) at 75 effective mAs (p < 0.001). In patients, noise was overall significantly (p = 0.025) reduced by 6.4% using the IC detector. Similar to the phantom, there was a gradual increase in noise reduction to 7.9% in patients with a body mass index of 25 kg/m(2) or lower (p = 0.008). Significant correlation was found in patients between noise and abdominal diameter in DC detector images (r = 0.604, p = 0.005), whereas no such correlation was found for the IC detector (r = 0.427, p = 0.060). Use of an IC detector in abdominal CT improves image quality and reduces image noise, particularly in overweight and obese patients. This noise reduction has the potential for dose reduction in abdominal CT.

  9. Quantification of myocardial blood flow using dynamic 320-row multi-detector CT as compared with 15O-H2O PET

    International Nuclear Information System (INIS)

    Kikuchi, Yasuka; Oyama-Manabe, Noriko; Kudo, Kohsuke; Naya, Masanao; Manabe, Osamu; Tomiyama, Yuuki; Tamaki, Nagara; Sasaki, Tsukasa; Katoh, Chietsugu; Shirato, Hiroki

    2014-01-01

    This study introduces a method to calculate myocardium blood flow (MBF) and coronary flow reserve (CFR) using the relatively low-dose dynamic 320-row multi-detector computed tomography (MDCT), validates the method against 15 O-H 2 O positron-emission tomography (PET) and assesses the CFRs of coronary artery disease (CAD) patients. Thirty-two subjects underwent both dynamic CT perfusion (CTP) and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group), the calculation method for MBF and CFR was established. In the other 13 normal subjects (validation group), MBF and CFR obtained by dynamic CTP and PET were compared. Finally, the CFRs obtained by dynamic CTP and PET were compared between the validation group and CAD patients (n = 7). Correlation between MBF of MDCT and PET was strong (r = 0.95, P CT in the CAD group (2.3 ± 0.8) was significantly lower than that in the validation group (5.2 ± 1.8) (P = 0.0011). We established a method for measuring MBF and CFR with the relatively low-dose dynamic MDCT. Lower CFR was well demonstrated in CAD patients by dynamic CTP. (orig.)

  10. Multi-scale analysis of lung computed tomography images

    CERN Document Server

    Gori, I; Fantacci, M E; Preite Martinez, A; Retico, A; De Mitri, I; Donadio, S; Fulcheri, C

    2007-01-01

    A computer-aided detection (CAD) system for the identification of lung internal nodules in low-dose multi-detector helical Computed Tomography (CT) images was developed in the framework of the MAGIC-5 project. The three modules of our lung CAD system, a segmentation algorithm for lung internal region identification, a multi-scale dot-enhancement filter for nodule candidate selection and a multi-scale neural technique for false positive finding reduction, are described. The results obtained on a dataset of low-dose and thin-slice CT scans are shown in terms of free response receiver operating characteristic (FROC) curves and discussed.

  11. 320-detector row CT coronary angiography in patients with arrhythmia

    International Nuclear Information System (INIS)

    Lu Li; Zhang Zhaoqi; Xu Lei; Yang Lin

    2011-01-01

    Objective: To evaluate the feasibility of CT coronary angiography (CTCA) in patients with arrhythmia using 320-detector row CT. Methods: Thirty-one patients with persistent atrial fibrillation and 8 patients with premature ventricular contraction were enrolled in this study. All patients underwent 320- detector row CTCA. CT image quality was evaluated with 4-point grading scale by two radiologists. Inter- observer agreement was evaluated by Kappa statistics. The radiation dose was calculated. Results: In total 510 coronary segments, 496 (97.2%) segments met diagnostic standard. The mean effective dose was (12.7±4.8) mSv in this study. There was a good agreement in image quality scoring between the two reviewers (Kappa = 0.72). Conclusion: 320-detector row CTCA is feasible in patients with atrial fibrillation and premature ventricular contraction. Arrhythmia may not be considered as a contraindication to CTCA. (authors)

  12. Carotid artery wall thickness and ischemic symptoms: evaluation using multi-detector-row CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saba, Luca; Caddeo, Giancarlo; Mallarini, Giorgio [Azienda Ospedaliero Universitaria Polo di Monserrato, Department of Radiology, Cagliari (Italy); Sanfilippo, Roberto; Montisci, Roberto [Azienda Ospedaliero Universitaria Polo di Monserrato, Department of Vascular Surgery, Cagliari (Italy); Pascalis, Luigi [Azienda Ospedaliero Universitaria Polo di Cagliari, Division of II Internal Medicine, Cagliari (Italy)

    2008-09-15

    The purpose of this study was to determine if carotid artery wall thickness (CAWT) studied by using multi-detector-row CT angiography (MDCTA) can be considered an effective parameter predictive of increased risk of stroke. A total of 217 patients were retrospectively studied by using MDCTA. In all patients CAWT was measured with an internal digital caliper. Continuous data were described as the mean value {+-} standard deviation (SD), and they were compared with Student's t-test. Scatter plots to determine interobserver agreement were performed, and correlation coefficient was calculated with Pearson statistics. A P value <0.05 was considered to mean statistical significance. Measurements of the distal common CAWT ranged from 0.5 to 1.6 mm. In the patient group without stroke, average CAWT was 0.82 mm (0.22 SD), whereas in patient group with stroke it was 1.096 mm (0.21 SD). CAWT in patients without stroke showed statistical difference (P<0.0001) when compared to patients with stroke. By using a threshold of 1 mm, an important statistical association between thick CAWT and stroke was found (P<0.0001). In fact, patients with {>=}1 mm CAWT had stroke with an odds ratio of 8.16 when compared with patients with <1 mm CAWT. Resulting data suggested that an increased CAWT is an indicator for risk of stroke. This parameter should be considered in addition to other well-known risk factors such as diabetes, hypertension, smoking, and dyslipidemia. (orig.)

  13. Carotid artery wall thickness and ischemic symptoms: evaluation using multi-detector-row CT angiography

    International Nuclear Information System (INIS)

    Saba, Luca; Caddeo, Giancarlo; Mallarini, Giorgio; Sanfilippo, Roberto; Montisci, Roberto; Pascalis, Luigi

    2008-01-01

    The purpose of this study was to determine if carotid artery wall thickness (CAWT) studied by using multi-detector-row CT angiography (MDCTA) can be considered an effective parameter predictive of increased risk of stroke. A total of 217 patients were retrospectively studied by using MDCTA. In all patients CAWT was measured with an internal digital caliper. Continuous data were described as the mean value ± standard deviation (SD), and they were compared with Student's t-test. Scatter plots to determine interobserver agreement were performed, and correlation coefficient was calculated with Pearson statistics. A P value <0.05 was considered to mean statistical significance. Measurements of the distal common CAWT ranged from 0.5 to 1.6 mm. In the patient group without stroke, average CAWT was 0.82 mm (0.22 SD), whereas in patient group with stroke it was 1.096 mm (0.21 SD). CAWT in patients without stroke showed statistical difference (P<0.0001) when compared to patients with stroke. By using a threshold of 1 mm, an important statistical association between thick CAWT and stroke was found (P<0.0001). In fact, patients with ≥1 mm CAWT had stroke with an odds ratio of 8.16 when compared with patients with <1 mm CAWT. Resulting data suggested that an increased CAWT is an indicator for risk of stroke. This parameter should be considered in addition to other well-known risk factors such as diabetes, hypertension, smoking, and dyslipidemia. (orig.)

  14. Carotid artery wall thickness and ischemic symptoms: evaluation using multi-detector-row CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saba, Luca; Caddeo, Giancarlo; Mallarini, Giorgio [Azienda Ospedaliero Universitaria Polo di Monserrato, Department of Radiology, Cagliari (Italy); Sanfilippo, Roberto; Montisci, Roberto [Azienda Ospedaliero Universitaria Polo di Monserrato, Department of Vascular Surgery, Cagliari (Italy); Pascalis, Luigi [Azienda Ospedaliero Universitaria Polo di Cagliari, Division of II Internal Medicine, Cagliari (Italy)

    2008-09-15

    The purpose of this study was to determine if carotid artery wall thickness (CAWT) studied by using multi-detector-row CT angiography (MDCTA) can be considered an effective parameter predictive of increased risk of stroke. A total of 217 patients were retrospectively studied by using MDCTA. In all patients CAWT was measured with an internal digital caliper. Continuous data were described as the mean value {+-} standard deviation (SD), and they were compared with Student's t-test. Scatter plots to determine interobserver agreement were performed, and correlation coefficient was calculated with Pearson statistics. A P value <0.05 was considered to mean statistical significance. Measurements of the distal common CAWT ranged from 0.5 to 1.6 mm. In the patient group without stroke, average CAWT was 0.82 mm (0.22 SD), whereas in patient group with stroke it was 1.096 mm (0.21 SD). CAWT in patients without stroke showed statistical difference (P<0.0001) when compared to patients with stroke. By using a threshold of 1 mm, an important statistical association between thick CAWT and stroke was found (P<0.0001). In fact, patients with {>=}1 mm CAWT had stroke with an odds ratio of 8.16 when compared with patients with <1 mm CAWT. Resulting data suggested that an increased CAWT is an indicator for risk of stroke. This parameter should be considered in addition to other well-known risk factors such as diabetes, hypertension, smoking, and dyslipidemia. (orig.)

  15. Cancerogenesis Risks between 64 and 320 Row Detector CT for Coronary CTA Screening

    Directory of Open Access Journals (Sweden)

    Atif N Khan

    2014-01-01

    Full Text Available Objectives: This study compares cancerogenesis risks posed by the 64 row detector and the 320 row detector computed tomography scanners used during coronary computed tomography angiography (CCTA following decennial screening guidelines. Material and Methods: Data of the radiation absorbed after CCTA by lung, thyroid, and female breast in patients between 50 and 70 years of age obtained from prior published literature for the 64 row CT scanner were compared with data from our study using 320 row detector CT scanner. Data from the 64 row and the 320 row detector CT scanners was used to determine lifetime attributable risks (LAR of cancer based on the biological effects of ionizing radiation (BEIR VII report. Results: The relative reduction of LAR (% for 50-, 60-, and 70-year-old patients undergoing scanning with the 320 row detector CT scanner was 30% lower for lung, and more than 50% lower for female breast when compared with results from 64 row detector CT scanner. The use of 320 row detector CT would result in a combined cumulative cancer incidence of less than 1/500 for breast in women and less than 1/1000 for lung in men; By comparison, this is much lower than other more common risk factors: 16-fold for lung cancer in persistent smokers, 2-fold for breast cancer with a first degree family member history of breast cancer, and 10-fold for thyroid cancer with a family member with thyroid cancer. Decennial screening would benefit at least 355,000 patients from sudden cardiac death each year, 94% of whom have significant coronary artery disease, with at least one stenosis >75%. LAR for thyroid cancer was negligible for both scanners. Conclusion: Lung and female breast LAR reductions with 320 row detector compared with 64 row detector CT are substantial, and the benefits would outweigh increased cancer risks with decennial screening in the age group of 50-70 years.

  16. CT findings of the thymus

    International Nuclear Information System (INIS)

    Kang, Eun Young; Kim, Yun Hwan; Seol, Hae Young; Chung, Woun Kyun; Suh, Won Hyuck

    1987-01-01

    In 14 cases of normal and abnormal thymus proved surgically and histopathologically in korea University Hae Wha Hospital during recent 6 years, the clinical and CT findings were analyzed. 1. Of 14 cases, 2 cases were normal thymus, 5 cases were thymic hyperplasia, 4 cases were benign thymoma, 2 case were malignant thymoma and 1 case was thymic cyst. 2. Of 14 cases, 10 cases were associated with myasthenia gravis, and 7 of these 10 cases were 3rd to 5th decades females. Among 10 cases with myasthenia gravis. 5 cases were thymic hyperplasia, 1 case was benign thymoma, 2 cases were malignant thymoma, and 2 cases were normal thymus. 3. All 5 thymic hyperplasia were associated with myasthenia gravis. CT findings of thymic hyperplasia were normal in 4 cases and increased lobe thickness in 1 case. 4. Of 4 cases of benign thymoma, only 1 case was associated with myasthenia gravis, and all 4 cases were positive findings in CT scan. CT findings of benign thymoma were round or oval soft tissue mass in anterior mediastinum, and 1 case had punctuate calcifications. 5. Of 2 cases of malignant thymoma, all 2 cases were associated with myasthenia gravis and positive findings in CT scan. CT findings of malignant thymoma were anterior mediastinal soft tissue mass with obliteration of the normal fat planes surrounding great vessels. SVC compression, and pleural tumor implants. 6. CT yielded significant diagnostic information of differential diagnosis between thymoma and thymoma hyperplasia in myasthenia gravis patients. Also CT was highly sensitive test in detection of thymoma and determined the extent and invasiveness of thymoma.

  17. CT findings of the thymus

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Eun Young; Kim, Yun Hwan; Seol, Hae Young; Chung, Woun Kyun; Suh, Won Hyuck [Korea University College of Medicine, Seoul (Korea, Republic of)

    1987-02-15

    In 14 cases of normal and abnormal thymus proved surgically and histopathologically in korea University Hae Wha Hospital during recent 6 years, the clinical and CT findings were analyzed. 1. Of 14 cases, 2 cases were normal thymus, 5 cases were thymic hyperplasia, 4 cases were benign thymoma, 2 case were malignant thymoma and 1 case was thymic cyst. 2. Of 14 cases, 10 cases were associated with myasthenia gravis, and 7 of these 10 cases were 3rd to 5th decades females. Among 10 cases with myasthenia gravis. 5 cases were thymic hyperplasia, 1 case was benign thymoma, 2 cases were malignant thymoma, and 2 cases were normal thymus. 3. All 5 thymic hyperplasia were associated with myasthenia gravis. CT findings of thymic hyperplasia were normal in 4 cases and increased lobe thickness in 1 case. 4. Of 4 cases of benign thymoma, only 1 case was associated with myasthenia gravis, and all 4 cases were positive findings in CT scan. CT findings of benign thymoma were round or oval soft tissue mass in anterior mediastinum, and 1 case had punctuate calcifications. 5. Of 2 cases of malignant thymoma, all 2 cases were associated with myasthenia gravis and positive findings in CT scan. CT findings of malignant thymoma were anterior mediastinal soft tissue mass with obliteration of the normal fat planes surrounding great vessels. SVC compression, and pleural tumor implants. 6. CT yielded significant diagnostic information of differential diagnosis between thymoma and thymoma hyperplasia in myasthenia gravis patients. Also CT was highly sensitive test in detection of thymoma and determined the extent and invasiveness of thymoma.

  18. CT findings of inoperable lung carcinoma

    International Nuclear Information System (INIS)

    Gay, S.B.; Black, W.C.

    1987-01-01

    CT is useful in the evaluation of patients with newly diagnosed or highly suspected lung cancer. The principal role of CT is to screen those patients with metastatic disease beyond the hili from an attempt at curative thoracotomy. While CT is regarded as very sensitive, it is not considered highly specific, and thus a surgical procedure is usually recommended for definitive diagnosis of most ''positive'' CT findings. However, the authors demonstrate a few characteristic CT findings that are highly predictive of unresectable metastatic disease. These CT findings include massive mediastinal lymphadenopathy, diffuse mediastinal infiltration, pericardial involvement, vascular encasement, and advanced chest wall invasion

  19. Ketamine-associated CT findings of damage in liver and gall and urinary system

    International Nuclear Information System (INIS)

    Zhang Keyun; Wang Lijuan; Wang Jiajun; Cheng Kuishan; Chen Aidi; Xu Dasheng

    2011-01-01

    Objective: To investigate the image signs of damage e in urinary system and liver and gall system and diagnostic value of CT findings in abuse of ketamine. Methods: With ethics committee approval, a retrospective analysis of 10 patients with a history of taking K powder (1 to 10 years) was done with abdominal CT scan and enhanced scan data to analysis the imaging findings of ketamine-related abdominal organ damage. Results: CT images of the 10 patients showed different degrees of reduced bladder capacity, bladder wall thickening range of 3∼14 mm. Of which the wall were thickened on both sides with the waist-shaped in 5 patients. Bilateral hydronephrosis and hydroureterosis was found in 3 cases with uniform wall thickening of both ureters. 4 cases of renal multi-lesion papillary necrosis was found, of which 2 patients showed multi-lesion ischemic changes in renal parenchyma in both kidneys. Expansion of the common bile duct appeared in 3 cases, of which 2 cases with merger intrahepatic bile duct dilation. Conclusion: CT findings of ketamine associated abdominal organ injuries in the bladder and renal may have certain characteristics. It is helpful to make diagnosis with the combination of favorable clinical data and medical history. (authors)

  20. Multi-detector CT evaluation in patients suspected of tracheobronchomalacia: Comparison of end-expiratory with dynamic expiratory volumetric acquisitions

    Energy Technology Data Exchange (ETDEWEB)

    Ferretti, Gilbert R. [Department of Radiology (France)], E-mail: gferretti@chu-grenoble.fr; Jankowski, Adrien [Department of Radiology (France)], E-mail: ajankowski@chu-grenoble.fr; Perrin, Marie Amelie [Department of Radiology (France)], E-mail: maperrin@chu-grenoble.fr; Chouri, Nathalie [Department of Respiratory Diseases (France)], E-mail: nchouri@chu-grenoble.fr; Arnol, Nathalie [Sleep Laboratory and EFCR, University Hospital, Grenoble (France); HP2 Laboratory, INSERM ERI 0017 (Hypoxia: Pathophysiology), Joseph Fourier University, Grenoble (France)], E-mail: narnold@chu-grenoble.fr; Aubaud, Laurent [Department of Radiology (France)], E-mail: laubaud@chu-grenoble.fr; Pepin, Jean-Louis [Sleep Laboratory and EFCR, University Hospital, Grenoble (France); HP2 Laboratory, INSERM ERI 0017 (Hypoxia: Pathophysiology), Joseph Fourier University, Grenoble (France)], E-mail: jlpepin@chu-grenoble.fr

    2008-11-15

    Purpose: The aim of this study was to compare dynamic expiratory imaging and end-expiratory imaging using multi-detector CT (MDCT) of the central airways in patients suspected of tracheobronchomalacia (TBM). Methods: This study had local ethical committee approval. Seventy patients suspected of TBM were prospectively included. All patients underwent evaluation of central airways by three different low-dose MDCT acquisitions: end inspiration, end expiration, and dynamic expiration. Degree of airway collapse was measured by calculating the percentage change in the area and diameter of the airways between inspiratory and the two expiratory techniques at three levels of the trachea and in the sagittal diameter of the right and left main bronchi. Three threshold levels of percentage reduction in diameter or area (30%, 50%, and 70%) for defining TBM were evaluated. Results: In the entire population, the mean percentage of airway collapse was significantly greater with dynamic expiratory imaging than with the end-expiratory imaging at three different levels: lower thoracic trachea (26% vs. 16.6%, p < 0.009), right (25.2% vs. 14%, p < 0.01) and left main (24.7% vs. 13.3%, p < 0.01) bronchus. Whatever the threshold value for defining TBM, dynamic expiratory imaging always resulted in diagnosing TBM in more patients than end-expiratory imaging. Conclusions: Dynamic expiratory imaging shows a significantly greater degree and a significantly greater extent of airway collapse than standard end-expiratory imaging in patients suspected of TBM. Further evaluation of the clinical relevance of such findings is warranted.

  1. CT findings in Reye syndrome

    International Nuclear Information System (INIS)

    Lee, Kil Woo; Lim, Hyo Keun; Choo, In Wook; Bae, Sang Hoon

    1990-01-01

    We present here the CT findings in 10 patients with Reye syndrome. Acute findings is diffuse cerebral swelling with or without parenchymal low density. The cerebral swelling gradually changed to atrophy. The parenchymal low density predisposes in Lt temporoparietal area. Contrast enhanced CT scan showed no additional finding, except 1 case. The hemorrhagic infarction which has not been reported previously was seen in 1 case and resulted in the most prominent sequela. The sequelae were developed in all atrophic cases. So, the brain CT may be useful in monitoring cerebral swelling, determining treatment plan in acute stage, and in presenting prognosis and sequelae on fellow up CT

  2. Coronary dual source multi detector computed tomography in patients suspected of coronary artery disease: Prevalence of incidental extra-cardiac findings

    International Nuclear Information System (INIS)

    Bendix, K.; Jensen, J.M.; Poulsen, S.; Mygind, N.; Norgaard, B.L.

    2011-01-01

    Objectives: (1) To establish the prevalence of incidental extra-cardiac findings (ECFs) in coronary multi detector computed tomography (CCT) performed in a large, homogeneous cohort of patients suspected of coronary artery disease (CAD). (2) To examine whether any association can be established between ECFs and pretest risk as determined by conventional risk factors for CAD, the Diamond-Forrester risk model or coronary artery calcium scores. (3) To assess cost related to extra-cardiac examinations. Design: Retrospective study of consecutive patients who had CCT performed. A large field of view was recreated from the non-enhanced CT scan and evaluated by a radiologist for incidental ECFs. Subjects: Patients with chest pain referred to CTA by a cardiologist. Results: In 1383 patients a total of 481 ECFs were indentified, 378 minor (meaning no follow-up was needed) and 103 major ECFs (ECF followed up clinically and/or with additional imaging), in a total of 393 (28%) patients. 85 (6%) patients had one major ECF and 9 (0.7%) patients had two major ECFs. In 19 (4 cases of malignancy) patients the major ECF had therapeutic consequences. Significant positive associations were found between age and smoking, respectively and the presence of ECFs. The cost estimate of saving one life from malignant disease based on ECF examinations is 40,190 Euro . Conclusion: Incidental extra-cardiac findings are common, sometimes revealing serious, even malignant disease. Diagnostic follow-up of major ECFs seems to be cost-effective in a Danish clinical setting. We recommend investigating a large field of view for incidental ECFs following CCT.

  3. Clinical application of multi-detector CT-guided percutaneous coaxial biopsy for pulmonary lesions

    International Nuclear Information System (INIS)

    Jia Ningyang; Liu Shiyuan; Zhang Dianbo; Xiao Xiangsheng; Li Wentao; Li Chenzhou

    2008-01-01

    Objective: To evaluate the clinical application of multi-slice CT-guided percutaneous transthoracic lung coaxial-biopsy for pulmonary lesions. Methods: 152 times of 143 patients were performed with percutaneous transthoracic coaxial biopsy under multiple-slice CT-guidance. Analysis was carried out to investigate the diagnostic accuracy and the relationship between the size of the lesions for coaxial biopsy, together with the complications. Results: The diagnostic accuracy was 94.9% with specificity of 100%, including malignant tumors 116 cases (squamous cell cancer 48 cases, adenocarcinoma 34, small cell undifferentiated carcinoma 6, large cell carcinoma 4, bronchial alveolar carcinoma 8, metastatic carcinoma 16) and 19 cases of benign ones(TB 7 cases, inflammatory pseudotumor 9, hematoma 1, lung abscess 1). The size of lesion had a significant influence on the diagnostic accuracy. Conclusions: Percutaneous transthoracic coaxial lung biopsy is a safety method, possessing a high diagnostic accuracy. (authors)

  4. The track finding algorithm of the Belle II vertex detectors

    Directory of Open Access Journals (Sweden)

    Bilka Tadeas

    2017-01-01

    Full Text Available The Belle II experiment is a high energy multi purpose particle detector operated at the asymmetric e+e− - collider SuperKEKB in Tsukuba (Japan. In this work we describe the algorithm performing the pattern recognition for inner tracking detector which consists of two layers of pixel detectors and four layers of double sided silicon strip detectors arranged around the interaction region. The track finding algorithm will be used both during the High Level Trigger on-line track reconstruction and during the off-line full reconstruction. It must provide good efficiency down to momenta as low as 50 MeV/c where material effects are sizeable even in an extremely thin detector as the VXD. In addition it has to be able to cope with the high occupancy of the Belle II detectors due to the background. The underlying concept of the track finding algorithm, as well as details of the implementation are outlined. The algorithm is proven to run with good performance on simulated ϒ(4S → BB̄ events with an efficiency for reconstructing tracks of above 90% over a wide range of momentum.

  5. Percutaneous sacroplasty with the use of C-arm flat-panel detector CT: technical feasibility and clinical outcome

    International Nuclear Information System (INIS)

    Kang, Sung Eun; Lee, Joon Woo; Kim, Joo Hyung; Kang, Heung Sik; Park, Kun Woo; Yeom, Jin S.

    2011-01-01

    Sacroplasty for sacral insufficiency fractures (SIFs) has been performed mostly under computed tomography (CT) or fluoroscopy guidance. The purposes of this study are to describe technical tips and clinical outcomes of sacroplasty under C-arm flat panel detector CT (C-arm CT) guidance, and to compare the cement distributions shown on C-arm CT with those on multi-detector CT (MDCT). This study consisted of patients who underwent sacroplasty for SIF using C-arm CT from May 2006 to May 2009. Technical success was assessed in terms of cement filling and leakage. Clinical outcome was assessed at short-term (less than 1 month) and long-term (more than 1 month) follow-up using a four-grade patient satisfaction scale: poor, fair, good, and excellent. After sacroplasty, all patients underwent MDCT and three radiologists compared MDCT images with C-arm CT images in consensus, focusing on the cement distribution and cement leakage. Sacroplasties were performed on both sacral alae in all 8 patients (male:female = 2:6, mean age = 76.9, range = 63-82). The technical success rate was 100%. At short-term follow up, 6 patients (87.5%) reported significant improvement. Five patients (62.5%) were available for long-term follow-up and all 5 patients reported a reduced pain and an improved ability to ambulate. Using MDCT as the standard of reference, the cement distribution was visualized equally well by C-arm CT. Sacroplasty under C-arm CT showed excellent technical success and good clinical outcome. There was an excellent correlation between C-arm CT and MDCT in evaluating cement distribution and cement leakage. (orig.)

  6. Percutaneous sacroplasty with the use of C-arm flat-panel detector CT: technical feasibility and clinical outcome

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sung Eun; Lee, Joon Woo; Kim, Joo Hyung; Kang, Heung Sik [Seoul National University Bundang Hospital, Department of Radiology, Gyeonggi-do (Korea, Republic of); Park, Kun Woo; Yeom, Jin S. [Seoul National University Bundang Hospital, Department of Orthopaedic Surgery, Gyeonggi-do (Korea, Republic of)

    2011-04-15

    Sacroplasty for sacral insufficiency fractures (SIFs) has been performed mostly under computed tomography (CT) or fluoroscopy guidance. The purposes of this study are to describe technical tips and clinical outcomes of sacroplasty under C-arm flat panel detector CT (C-arm CT) guidance, and to compare the cement distributions shown on C-arm CT with those on multi-detector CT (MDCT). This study consisted of patients who underwent sacroplasty for SIF using C-arm CT from May 2006 to May 2009. Technical success was assessed in terms of cement filling and leakage. Clinical outcome was assessed at short-term (less than 1 month) and long-term (more than 1 month) follow-up using a four-grade patient satisfaction scale: poor, fair, good, and excellent. After sacroplasty, all patients underwent MDCT and three radiologists compared MDCT images with C-arm CT images in consensus, focusing on the cement distribution and cement leakage. Sacroplasties were performed on both sacral alae in all 8 patients (male:female = 2:6, mean age = 76.9, range = 63-82). The technical success rate was 100%. At short-term follow up, 6 patients (87.5%) reported significant improvement. Five patients (62.5%) were available for long-term follow-up and all 5 patients reported a reduced pain and an improved ability to ambulate. Using MDCT as the standard of reference, the cement distribution was visualized equally well by C-arm CT. Sacroplasty under C-arm CT showed excellent technical success and good clinical outcome. There was an excellent correlation between C-arm CT and MDCT in evaluating cement distribution and cement leakage. (orig.)

  7. How many CT detector rows are necessary to perform adequate three dimensional visualization?

    International Nuclear Information System (INIS)

    Fischer, Lars; Tetzlaff, Ralf; Schoebinger, Max; Radeleff, Boris; Bruckner, Thomas; Meinzer, H.P.; Buechler, M.W.; Schemmer, Peter

    2010-01-01

    Introduction: The technical development of computer tomography (CT) imaging has experienced great progress. As consequence, CT data to be used for 3D visualization is not only based on 4 row CTs and 16 row CTs but also on 64 row CTs, respectively. The main goal of this study was to examine whether the increased amount of CT detector rows is correlated with improved quality of the 3D images. Material and Methods: All CTs were acquired during routinely performed preoperative evaluation. Overall, there were 12 data sets based on 4 detector row CT, 12 data sets based on 16 detector row CT, and 10 data sets based on 64 detector row CT. Imaging data sets were transferred to the DKFZ Heidelberg using the CHILI teleradiology system. For the analysis all CT scans were examined in a blinded fashion, i.e. both the name of the patient as well as the name of the CT brand were erased. For analysis, the time for segmentation of liver, both portal and hepatic veins as well as the branching depth of portal veins and hepatic veins was recorded automatically. In addition, all results were validated in a blinded fashion based on given quality index. Results: Segmentation of the liver was performed in significantly shorter time (p < 0.01, Kruskal-Wallis test) in the 16 row CT (median 479 s) compared to 4 row CT (median 611 s), and 64 row CT (median 670 s), respectively. The branching depth of the portal vein did not differ significantly among the 3 different data sets (p = 0.37, Kruskal-Wallis test). However, the branching depth of the hepatic veins was significantly better (p = 0.028, Kruskal-Wallis test) in the 4 row CT and 16 row CT compared to 64 row CT. The grading of the quality index was not statistically different for portal veins and hepatic veins (p = 0.80, Kruskal-Wallis test). Even though the total quality index was better for the vessel tree based on 64 row CT data sets (mean scale 2.6) compared to 4 CT row data (mean scale 3.25) and 16 row CT data (mean scale 3.0), these

  8. Thoracic Injuries in earthquake-related versus non-earthquake-related trauma patients: differentiation via Multi-detector Computed Tomography

    Science.gov (United States)

    Dong, Zhi-hui; Yang, Zhi-gang; Chen, Tian-wu; Chu, Zhi-gang; Deng, Wen; Shao, Heng

    2011-01-01

    PURPOSE: Massive earthquakes are harmful to humankind. This study of a historical cohort aimed to investigate the difference between earthquake-related crush thoracic traumas and thoracic traumas unrelated to earthquakes using a multi-detector Computed Tomography (CT). METHODS: We retrospectively compared an earthquake-exposed cohort of 215 thoracic trauma crush victims of the Sichuan earthquake to a cohort of 215 non-earthquake-related thoracic trauma patients, focusing on the lesions and coexisting injuries to the thoracic cage and the pulmonary parenchyma and pleura using a multi-detector CT. RESULTS: The incidence of rib fracture was elevated in the earthquake-exposed cohort (143 vs. 66 patients in the non-earthquake-exposed cohort, Risk Ratio (RR) = 2.2; pchest (45/143 vs. 11/66 patients, RR = 1.9; ptraumas resulting from the earthquake were life threatening with a high incidence of bony thoracic fractures. The ribs were frequently involved in bilateral and severe types of fractures, which were accompanied by non-rib fractures, pulmonary parenchymal and pleural injuries. PMID:21789386

  9. Acute pancreatitis: clinical vs. CT findings

    International Nuclear Information System (INIS)

    Hill, M.C.; Barkin, J.; Isikoff, M.B.; Silver stein, W.; Kalser, M.

    1982-01-01

    In a prospective study of 91 patients with acute pancreatitis, computed tomographic (CT) findings were correlated with the clinical type of acute pancreatitis. In acute edematous pancreatitis (63 patients; 16 with repeat CT), CT was normal (28%) or showed inflammation limited to the pancreas (61%). Phlegmonous changes were present in 11%, including one patient with focal pancreatic hemorrhage, indicating that clinically unsuspected hemorrhagic pancreatitis can occur. In acute necrotizing (hemorrhagic, suppurative) pancreatitis (nine patients; eight with repeat CT), no patient had a normal CT scan and 89% had phlegmonous changes. One patient had hemorrhagic pancreatitis and three had abscesses. In acute exacerbation of chronic pancreatitis (10 patients; three with repeat CT), there were pancreatic calcifications (70%), a focal mass (40%), and pancreatic ductal dilation (30%). On follow-up CT, the findings of acute pancreatitis did not always disappear with resolution of the clinical symptons. This was especialy true of phlegmonous pancreatitis, where the CT findings could persist for months

  10. CT scan findings in focal epilepsy

    International Nuclear Information System (INIS)

    Kobayashi, Eiki; Mihara, Tadahiro; Yamamoto, Kunimitsu; Yamashita, Kenji; Asakura, Tetsuhiko

    1980-01-01

    In 80 cases of focal epilepsy, excluding such cases as late onset after the age of 30 and traumatic or expansive lesions, the epileptogenic foci have been studied by comparing the CT findings with the seizure types and the EEG findings. The results were as follows: (1) Abnormal CT findings were observed in 36% of the patients. (2) These findings were classified into 4 large groups: localized cerebral atrophy, localized low density, localized high density with contrast enhancement and diffuse cerebral atrophy. (3) The incidence of CT abnormality was higher in the cases with continuous and localized EEG abnormality than in the cases with other types of EEG abnormality. In 48% of the cases, the location of the abnormal CT findings coincided with their EEG foci. (4) In the cases of temporal lobe epilepsy without abnormal CT images, the print-out data compared with the bilateral promised temporal regions, before and after contrast enhancement. The EMI-No. of the medial temporal focus increased more than that of the contralateral side in 3 cases out of 4 after contrast-media injection. (5) Moreover, for the purpose of comparing the CT findings on general seizures with those in focal seizures, we have studied 80 cases of general seizures. In the cases of the general seizures, abnormal CT findings were observed in only 16%. These abnormal findings were diffuse in 5 cases, localized in 6 cases, and combined in 3 cases. (author)

  11. Assessment of vertebral artery stents using 16-slice multi-detector row CT angiography in vivo evaluation: Comparison of a medium-smooth kernel and a sharp kernel

    International Nuclear Information System (INIS)

    Yoo, Won Jong; Lim, Yeon Soo; Ahn, Kook Jin; Choi, Byung Gil; Kim, Ji Young; Kim, Sung Hoon

    2009-01-01

    Objectives: To assess the lumen visibility of extracranial vertebral artery stents examined with 16-slice multi-detector row computed tomography (MDCT) angiography in vivo using a medium-smooth kernel (B30s) and a sharp kernel (B60s), and to compare these with digital subtraction angiography (DSA) after stent placement. Methods: Twenty stents from 20 patients (14 men, 6 women; mean age, 62.7 ± 10.1 years) who underwent CT angiography (CTA) with 16-slice MDCT were retrospectively analyzed. In CT angiograms using a B30s and a B60s, the lumen diameters and CT attenuations of the stented vessels were measured three times by three observers, and artificial luminal narrowing (ALN) was calculated. To assess measurement reliability on CT angiograms, the intraclass correlation coefficient (ICC) was used. DSA served as the reference standard for the in-stent luminal measurements on CT angiography. The median interval between CT angiography and DSA was 1 day (range 1-10). Results: For interobserver reliability, intraclass correlation coefficients for the lumen diameters on CT angiograms with a B30s and a B60s were 0.90 and 0.96, respectively. The lumen diameters on CT angiograms using a B30s were consistently smaller than that on CT angiograms using a B60s (p < 0.01). The mean ALN was 37 ± 7% on CT angiograms using a B30s and 25 ± 9% on CT angiograms using a B60s. The mean CT attenuation in in-stent lumen was 347 ± 55 HU on CT angiograms using a B30s and 295 ± 46 HU on CT angiograms using a B60s. The ALN and CT attenuation within the stented vessels between CT angiograms using a B30s and a B60s was significant (p < 0.01). Conclusions: 16-slice MDCT using a sharp kernel allows good visualization of the stented vessels and is useful in the assessment of vertebral artery stent patency after stent placement.

  12. Mediastinal and hilar lymphadenopathy: cross-referenced anatomy on axial and coronal images displayed by using multi-detector row CT

    International Nuclear Information System (INIS)

    Lee, Ju Hyun; Lee, Kyung Soo; Kim, Tae Sung; Yi, Chin A; Cho, Jae Min; Lee, Min Hee

    2003-01-01

    The accurate evaluation of mediastinal and pulmonary hilar lymphadenopathy, especially in patients with lung cancer, is important for determining treatment options and evaluating the response to therapy. To indicate nodal location in detail, mediastinal and hilar lymph nodes have been assigned to one of 14 nodal stations. Mediastinal nodes of greater than 10 mm short-axis diameter are regarded as abnormal, irrespective of their nodal station, while hilar nodes are considered abnormal if their diameter is greater than 10 mm in any axis or they are convex compared to surrounding lung. By providing multiplanar images, multi-detector row CT allows detailed evaluation of thoracic anatomic structures more easily than in the past, when axial images only were available. At cross-referenced imaging, a lymph node depicted at axial imaging in one anatomical location can be visualized simultaneously and automatically at coronal imaging at the exactly corresponding anatomical location. Cross-referenced coincidental axial and coronal images help assess both the size and morphology of mediastinal and hilar lymph nodes

  13. CT findings at lupus mesenteric vasculitis

    International Nuclear Information System (INIS)

    Ko, S.F.; Lee, T.Y.; Cheng, T.T.; Ng, S.H.; Lai, H.M.; Cheng, Y.F.; Tsai, C.C.

    1997-01-01

    Purpose: To describe the spectrum of early CT findings of lupus mesenteric vasculitis (LMV) and to assess the utility of CT in the management of this uncommon entity. Methods: Abdominal CT was performed within 1-4 days (average 2.2 days) of the onset of severe abdominal pain and tenderness in 15 women with systemic lupus erythematosus. Prompt high-dose i.v. corticosteroid in 11 patients after the CT diagnosis of LMV was made. CT was performed after abdominal symptoms subsided. Results: Eleven cases revealed CT features suggestive of LMV including conspicuous prominence of mesentric vessels with palisade pattern or comb-like appearance (CT comb sign) supplying focal or diffuse dilated bowel loops (n=11), ascites with slightly increased peritoneal enhancement (n=11), small bowel wall thickening (n=10) with double halo or target sign (n=8). Follow-up CT before high-dose steroid therapy revealed complete or marked resolution of the abnormal CT findings. Conclusion: CT is helpful for confirming the diagnosis of LMV, especially the comb sign which may be an early sign. Bowel ischemia due to LMV is less ominous than previously expected, and the abnormal CT findings were reversible when early diagnosis and prompt i.v. steroid therapy could be achieved. (orig.)

  14. CT findings at lupus mesenteric vasculitis

    Energy Technology Data Exchange (ETDEWEB)

    Ko, S.F. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan); Lee, T.Y. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan); Cheng, T.T. [Chang Gung Medical College and Memorial Hospital, Dept. of Rheumatology, Kaohsiung Hsien (Taiwan); Ng, S.H. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan); Lai, H.M. [Chang Gung Medical College and Memorial Hospital, Dept. of Rheumatology, Kaohsiung Hsien (Taiwan); Cheng, Y.F. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan); Tsai, C.C. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan)

    1997-01-01

    Purpose: To describe the spectrum of early CT findings of lupus mesenteric vasculitis (LMV) and to assess the utility of CT in the management of this uncommon entity. Methods: Abdominal CT was performed within 1-4 days (average 2.2 days) of the onset of severe abdominal pain and tenderness in 15 women with systemic lupus erythematosus. Prompt high-dose i.v. corticosteroid in 11 patients after the CT diagnosis of LMV was made. CT was performed after abdominal symptoms subsided. Results: Eleven cases revealed CT features suggestive of LMV including conspicuous prominence of mesentric vessels with palisade pattern or comb-like appearance (CT comb sign) supplying focal or diffuse dilated bowel loops (n=11), ascites with slightly increased peritoneal enhancement (n=11), small bowel wall thickening (n=10) with double halo or target sign (n=8). Follow-up CT before high-dose steroid therapy revealed complete or marked resolution of the abnormal CT findings. Conclusion: CT is helpful for confirming the diagnosis of LMV, especially the comb sign which may be an early sign. Bowel ischemia due to LMV is less ominous than previously expected, and the abnormal CT findings were reversible when early diagnosis and prompt i.v. steroid therapy could be achieved. (orig.).

  15. Respiratory gated lung CT using 320-row area detector CT

    International Nuclear Information System (INIS)

    Sakamoto, Ryo; Noma, Satoshi; Higashino, Takanori

    2010-01-01

    Three hundred and twenty-row Area Detector CT (ADCT) has made it possible to scan whole lung field with prospective respiratory gated wide volume scan. We evaluated whether the respiratory gated wide volume scan enables to reduce motion induced artifacts in the lung area. Helical scan and respiratory gated wide volume scan were performed in 5 patients and 10 healthy volunteers under spontaneous breathing. Significant reduction of motion artifact and superior image quality were obtained in respiratory gated scan in comparison with helical scan. Respiratory gated wide volume scan is an unique method using ADCT, and is able to reduce motion artifacts in lung CT scans of patients unable to suspend respiration in clinical scenes. (author)

  16. A multi-channel photometric detector for multi-component analysis in flow injection analysis.

    Science.gov (United States)

    Tan, A; Huang, J; Geng, L; Xu, J; Zhao, X

    1994-01-01

    The detector, a multi-channel photometric detector, described in this paper was developed using multi-wavelength LEDs (light emitting diode) and phototransistors for absorbance measurement controlled by an Intel 8031 8-bit single chip microcomputer. Up to four flow cells can be attached to the detector. The LEDs and phototransistors are both inexpensive, and reliable. The results given by the detector for simultaneous determination of trace amounts of cobalt and cadmium in zinc sulphate electrolyte are reported. Because of the newly developed detector, this approach employs much less hardware apparatus than by employing conventional photometric detectors.

  17. Evaluation of spinal cord vessels using multi-slice CT angiography

    International Nuclear Information System (INIS)

    Chen Shuang; Zhu Ruijiang; Feng Xiaoyuan

    2006-01-01

    Objective: To evaluate the value of Multi-slice spiral CT angiography for spinal cord vessels. Methods: 11 adult subjects with suspected of myelopathy were performed with Multi-slice spiral CT angiography, An iodine contrast agent was injected at 3.5 ml/s, for total 100 ml. The parameters were axial 16 slice mode, 0.625 mm slice thickness, 0.8 s rotation, delay time depending on smartprep(15-25 s), multi-phase scan. The coronal and sagittal MPR and SSD were generated on a workstation compared with spinal digital subtraction angiography (DSA) to analyze normal or abnormal spinal cord vessels. Results: Normal findings at spinal CTA and digital subtraction angiography in six adult normal subjects and spinal cord vascular malformations (1 intradural extramedullary AVF, 4 dural AVFs) in five cases, Recognizable intradural vessels corresponding to anterior median (midline) veins and/or anterior spinal arteries were show in six adult normal subjects. Abnormal intradural vessels were detected in all five spinal cord vascular malformation with CT angiography, in comparison with digital subtraction angiography these vessels were primarily enlarged veins of the coronal venous plexus on the cord surface, radiculomedullary-dural arteries could not be clearly shown in four dural AVF, only one anterior spinal artery was detected in one patient with intradural medullary AVF, which direct shunt between anterior spinal artery and perimedullary vein with tortuous draining vessel. Conclusion: Multi-slice CT angiography is able to visualize the normal or abnormal spinal cord vessels. It could be used as a noninvasive method to screen the spinal cord vascular disease. (authors)

  18. CT findings of exophageal perforation

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Jeong Nam; Choi, Yo Won; Jeon, Seok Chol; Park, Choong Ki; Hahm, Chang Kok [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2002-09-01

    To determine which CT findings are useful for the early disgnosis of esophageal perforation, and on the basis of these findings, to assess the accuracy of prediction of the perforation site. A review of medical records indicated that between January 1995 and December 2001, 36 patients with esophageal perforation were admitted to our hospital. Thirteen of these [M:F=8:5, age; 28-69 (mean, 52.4) years], who had undergone CT chest scanning, were included in this study. The causes of esophageal perforation were trauma (n=5), infectious diseases (n=4), Boerhaave syndrome (n=1), lung cancer (n=1), esophageal cancer (n=1), and idiopathic. Two chest radiologists unaware of the clinical findings reviewed the CT scans and predicted whether the upper or lower esophagus was perforated. The most common CT finding was extraluminal air at the posterior mediastinum (n=11), while other findings included pulmonary consolidation (n=10), pleural effusion (n=7), discontinuity of the esophageal wall (n=6) and subcutaneous emphysema (n=4), fluid collection around the esophagus (n-4), esophageal wall thickening (n=4), pneumothorax (n=2), and lung abscess (n=2). The perforation site was accurately predicted in 76.9% of cases (10/13). The CT findings which help the diagnosis of esophageal perforation, and prediction of the sites at which it occurs, are extraluminal air of fluid collection, focal defect of the esophageal wall, and esophageal wall thickening.

  19. CT findings of exophageal perforation

    International Nuclear Information System (INIS)

    Heo, Jeong Nam; Choi, Yo Won; Jeon, Seok Chol; Park, Choong Ki; Hahm, Chang Kok

    2002-01-01

    To determine which CT findings are useful for the early disgnosis of esophageal perforation, and on the basis of these findings, to assess the accuracy of prediction of the perforation site. A review of medical records indicated that between January 1995 and December 2001, 36 patients with esophageal perforation were admitted to our hospital. Thirteen of these [M:F=8:5, age; 28-69 (mean, 52.4) years], who had undergone CT chest scanning, were included in this study. The causes of esophageal perforation were trauma (n=5), infectious diseases (n=4), Boerhaave syndrome (n=1), lung cancer (n=1), esophageal cancer (n=1), and idiopathic. Two chest radiologists unaware of the clinical findings reviewed the CT scans and predicted whether the upper or lower esophagus was perforated. The most common CT finding was extraluminal air at the posterior mediastinum (n=11), while other findings included pulmonary consolidation (n=10), pleural effusion (n=7), discontinuity of the esophageal wall (n=6) and subcutaneous emphysema (n=4), fluid collection around the esophagus (n-4), esophageal wall thickening (n=4), pneumothorax (n=2), and lung abscess (n=2). The perforation site was accurately predicted in 76.9% of cases (10/13). The CT findings which help the diagnosis of esophageal perforation, and prediction of the sites at which it occurs, are extraluminal air of fluid collection, focal defect of the esophageal wall, and esophageal wall thickening

  20. WE-B-207-01: CT Lung Cancer Screening and the Medical Physicist: Background, Findings and Participant Dosimetry Summary of the National Lung Screening Trial (NLST)

    International Nuclear Information System (INIS)

    Kruger, R.

    2015-01-01

    The US National Lung Screening Trial (NLST) was a multi-center randomized, controlled trial comparing a low-dose CT (LDCT) to posterior-anterior (PA) chest x-ray (CXR) in screening older, current and former heavy smokers for early detection of lung cancer. Recruitment was launched in September 2002 and ended in April 2004 when 53,454 participants had been randomized at 33 screening sites in equal proportions. Funded by the National Cancer Institute this trial demonstrated that LDCT screening reduced lung cancer mortality. The US Preventive Services Task Force (USPSTF) cited NLST findings and conclusions in its deliberations and analysis of lung cancer screening. Under the 2010 Patient Protection and Affordable Care Act, the USPSTF favorable recommendation regarding lung cancer CT screening assisted in obtaining third-party payers coverage for screening. The objective of this session is to provide an introduction to the NLST and the trial findings, in addition to a comprehensive review of the dosimetry investigations and assessments completed using individual NLST participant CT and CXR examinations. Session presentations will review and discuss the findings of two independent assessments, a CXR assessment and the findings of a CT investigation calculating individual organ dosimetry values. The CXR assessment reviewed a total of 73,733 chest x-ray exams that were performed on 92 chest imaging systems of which 66,157 participant examinations were used. The CT organ dosimetry investigation collected scan parameters from 23,773 CT examinations; a subset of the 75,133 CT examinations performed using 97 multi-detector CT scanners. Organ dose conversion coefficients were calculated using a Monte Carlo code. An experimentally-validated CT scanner simulation was coupled with 193 adult hybrid computational phantoms representing the height and weight of the current U.S. population. The dose to selected organs was calculated using the organ dose library and the abstracted scan

  1. WE-B-207-01: CT Lung Cancer Screening and the Medical Physicist: Background, Findings and Participant Dosimetry Summary of the National Lung Screening Trial (NLST)

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, R. [Marshfield Clinic, Marshfield, WI (United States)

    2015-06-15

    The US National Lung Screening Trial (NLST) was a multi-center randomized, controlled trial comparing a low-dose CT (LDCT) to posterior-anterior (PA) chest x-ray (CXR) in screening older, current and former heavy smokers for early detection of lung cancer. Recruitment was launched in September 2002 and ended in April 2004 when 53,454 participants had been randomized at 33 screening sites in equal proportions. Funded by the National Cancer Institute this trial demonstrated that LDCT screening reduced lung cancer mortality. The US Preventive Services Task Force (USPSTF) cited NLST findings and conclusions in its deliberations and analysis of lung cancer screening. Under the 2010 Patient Protection and Affordable Care Act, the USPSTF favorable recommendation regarding lung cancer CT screening assisted in obtaining third-party payers coverage for screening. The objective of this session is to provide an introduction to the NLST and the trial findings, in addition to a comprehensive review of the dosimetry investigations and assessments completed using individual NLST participant CT and CXR examinations. Session presentations will review and discuss the findings of two independent assessments, a CXR assessment and the findings of a CT investigation calculating individual organ dosimetry values. The CXR assessment reviewed a total of 73,733 chest x-ray exams that were performed on 92 chest imaging systems of which 66,157 participant examinations were used. The CT organ dosimetry investigation collected scan parameters from 23,773 CT examinations; a subset of the 75,133 CT examinations performed using 97 multi-detector CT scanners. Organ dose conversion coefficients were calculated using a Monte Carlo code. An experimentally-validated CT scanner simulation was coupled with 193 adult hybrid computational phantoms representing the height and weight of the current U.S. population. The dose to selected organs was calculated using the organ dose library and the abstracted scan

  2. CT findings of orbital inflammatory diseases

    International Nuclear Information System (INIS)

    Kim, Jang Min; Shin, Hyun Joon; Kim, Jung Hyuk; Suh, Won Hyuck

    1991-01-01

    Twenty-nine patients with orbital inflammatory disease (OIDs) were retrospectively reviewed in order to analyze detailed CT findings which might aid in differentiating OIDs. This study comprised 18 pseudotumors, 5 thyroid ophthalmopathies, and 6 cases of orbital cellulitis. CT scans of the pseudotumors showed various findings such as exophthalmos, scleritis, myositis of the extraocular muscle (MOM), and bone lesion. Bone lesions of the pseudo tumors, which have been rarely reported, were present in 7 cases in our series. Bilateral exophthalmos, myositis, and retrobulbar fat deposition were readily detected by CT in thyroid ophthalmopathy, and, in addition, we found bone erosions involving the orbital apices in 2 cases. In orbital cellulitis, extraorbital soft tissue swelling and lateral displacement of the medial rectus muscle in cases with ethmoiditis were the most conspicuous features. In summary, because of the overlapping CT findings in OIDs, careful examination of CT findings regarding the mode of EOM involvement and the presence or absence of scleritis or sinusitis might help narrow down the differential diagnosis. A pseudotumor with bone lesions could be mistaken as a malignant lesion, and therefore it is necessary to correlate clinical features with CT findings for an accurate diagnosis

  3. CT findings of slilcosis

    International Nuclear Information System (INIS)

    Jung, Dong Hee; Kim, Kun Il; Son, Hyun Ju; Ro, Young Jin; Jung, Doo Young; Park, Jae Yeong; Lee, Jun Woo; Kim, Byung Soo

    1996-01-01

    To describe chest radiographic and CT findings of silicosis, and to compare their findings. Ten coal miners and six stonemasons were included in this study. All were male and their mean age was 53.1. The mean duration of dust exposure was 15.2 years(range, 5-30 years) in coal miners and 25.3 years(range, 15-35 years) in stonemasons. Chest radiographs(n=16), conventional CT scans(n=4), and high resolution CT(HRCT) scans(n=13) were evaluated. Parenchymal abnormalities were interpreted on the basis of ILO standard films(1980) in chest radiographs and on the basis of CAP(College of American Pathologists, 1979) in CT(HRCT) films. Chest radiographs revealed large opacities(n=8), small opacities(n=6), and normal findings(n=2). Type r(n=4) and category 1/1(n=2) were most common for small opacities, while for large opacities, category B(n=4) and category c(n=4) were most common. These small and large opacities were located predominantly in the area of the upper and middle lung. Associated findings were emphysema(n=7), eggshell nodal calcifications(n=3), pneumothorax(n=3), C-P angle blunting(n=4), and pleural thickening(n=1). CT scans revealed micronodules(n=16), nodules(n=3), and progressive massive fibrosis(PMF, n=8). All these lesions were located in the upper and middle lungs, especially in the central portion of the posterior lung. PMF showed diffuse and homogenous(n=3) and puntate(n=2) calcifications, cavitations(n=5), air bronchograms(n=3), and necrosis(n=1). Peripheral paracicatrical emphysema was associated with PMF(n=8). Other findings were pneumothorax(n=4), emphysema(n=10), hilar and mediastinal nodal enlargement(n=11) bronchial wall thick- enings(n=6), bronchiectasis(n=1), pleural thickening(n=7), parenchymal fibrosis(n=1), and pulmonary tuberculosis(n=2). Small and large opacities in chest radiographs and micronodules, nodules, and PMFs in CT (HRCT) films were located predominately in the upper and middle lungs, especially in the central portion of the

  4. Double Chooz Improved Multi-Detector Measurements

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    The Double Chooz experiment (DC) is a reactor neutrino oscillation experiment running at Chooz nuclear power plant (2 reactors) in France. In 2011, DC first reported indication of non-zero θ13 with the far detector (FD) located at the maximum of oscillation effects (i.e. disappearance), thus challenging the CHOOZ non-observation limit. A robust observation of θ13 followed in 2012 by the Daya Bay experiments with multiple detector configurations. Since 2015 DC runs in a multi-detector configuration making thus the impact of several otherwise dominating systematics reduce strongly. DC’s unique almost "iso-flux" site, allows the near detector (ND) to become a direct accurate non-oscillation reference to the FD. Our first multi-detector results at MORIOND-2016 showed an intriguing deviation of θ13 with respect to the world average. We will address this issue in this seminar. The combined "reactor-θ13" measurement is expected to ...

  5. CT findings of colonic diverticulitis

    International Nuclear Information System (INIS)

    Sasaki, Shigeru; Ohba, Satoru; Mizutani, Masaru

    1998-01-01

    Although colonic diverticulitis has no indication for operation, but in some mistaken cases were operated with a diagnosis of acute appendicitis. We evaluated the CT findings of colonic diverticulitis about 19 cases and of asymptomatic colonic diverticula about 15 cases retrospectively. Diagnosis was confirmed of barium enema and operation. CT are complementary methods of examination that can delineated the range of thickening of the colon and the extension of inflammatory changes around the colon. We also believe that CT findings of colonic diverticulitis are useful for differentiating from a diagnosis of appendicitis. (author)

  6. Multi-detector thoracic CT findings in cerebro-costo-mandibular syndrome: rib gaps and failure of costo-vertebral separation.

    Science.gov (United States)

    Watson, Tom Anthony; Arthurs, Owen John; Muthialu, Nagarajan; Calder, Alistair Duncan

    2014-02-01

    Cerebro-costo-mandibular syndrome (CCMS) describes a triad of mandibular hypoplasia, brain dysfunction and posterior rib defects ("rib gaps"). We present the CT imaging for a 2-year-old girl with CCMS that highlights the rib gap defects and shows absent transverse processes with abnormal fusion of the ribs directly to the vertebral bodies. We argue that this is likely to relate to abnormal lateral sclerotome development in embryology, with the failure of normal costo-vertebral junctions compounding impaired thoracic function. The case also highlights the use of CT for specific indications in skeletal dysplasia.

  7. Multi-energy spectral CT: adding value in emergency body imaging.

    Science.gov (United States)

    Punjabi, Gopal V

    2018-04-01

    Most vendors offer scanners capable of dual- or multi-energy computed tomography (CT) imaging. Advantages of multi-energy CT scanning include superior tissue characterization, detection of subtle iodine uptake differences, and opportunities to reduce contrast dose. However, utilization of this technology in the emergency department (ED) remains low. The purpose of this pictorial essay is to illustrate the value of multi-energy CT scanning in emergency body imaging.

  8. CT findings of exophytic hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Jin; Cho, June Sik; Kim, Hyung Lyul; Lee, Chung Keun; Kim, Dae Hong; Rhee, Byung Chull [Chungnam National University College of Medicine, Daejeon (Korea, Republic of)

    1993-11-15

    We retrospectively evaluated the characteristic computed tomographic(CT) findings in nine patients with exohepatic hepatocellular carcinoma(HCC) pathologically prove by surgery(n=2) or percutaneous needle biopsy(n=7). The CT findings of exphepatic HCC were correlated with clinical findings and compared with those of usual HCC. Lesions were in the left lobe(n=7) and right lobe(n=2) of the liver. All lesions showed a well-marginated hypodense mass with capsular enhancement on enhanced CT scan. The patterns of capsular enhancement were complete in five and partial in four case. The portal vein thrombosis was seen only in one case. There was no difference between exohepatic HCC and usual HCC in clinical findings such as increased {alpha}-fetoprotein({alpha}-FP), positive hepatitis B surface antigen(HBsAg), and underlying liver cirrhosis. In conclusion, the CT findings of exohepatic HCC were a well-defined hyperdense mass with complete or partial capsular enhancement and these findings may be useful in differentiation from the tumors of adjacent organs.

  9. New developments in PET detector technology

    International Nuclear Information System (INIS)

    Niu Lingxin; Zhao Shujun; Zhang Bin; Liu Haojia

    2010-01-01

    The researches on PET detector are always active and innovative area. The research direction of PET detector includes improving performances of scintillator-based detectors, investigating new detectors suitable for multi-modality imaging (e.g. PET/CT and PET/MRI), meeting requirements of TOF and DOI technologies and boosting the development of the technologies. In this paper, new developments in PET detector technology about scintillation crystal, photodetector and semiconductor detector is introduced. (authors)

  10. Data acquisition for experiments with multi-detector arrays

    Indian Academy of Sciences (India)

    Experiments with multi-detector arrays have special requirements and place higher demands on computer data acquisition systems. In this contribution we discuss data acquisition systems with special emphasis on multi-detector arrays and in particular we describe a new data acquisition system, AMPS which we have ...

  11. Impact of multi-detector row computed tomography on the tactics of cardiovascular surgery. From qualitative evaluation to quantitative assessment

    International Nuclear Information System (INIS)

    Imagawa, Hiroshi; Kawachi, Kanji; Takano, Shinji

    2005-01-01

    We assessed the role of multi-detector row computed tomography in cardiovascular surgery. The efficacy of multi-detector row computed tomography was assessed concerning the graft patency of coronary artery bypass, arterial atheromatous degeneration, small vessel imaging, and left ventricular volume measurement. Images were reconstructed using both the volume-rendering and the maximum-intensity-profile methods. Arterial atherosclerotic degeneration was assessed by aortic wall volume and aortic calcification volume. In the assessment of bypass graft patency, multidetector row computed tomography showed a 98% correct positive ratio with sensitivity and specificity of 98% and 100%, respectively. Atheromatous degeneration showed matching results in more than 70% of cases compared with intraoperative findings. More than 92% of arterial branches with diameters of 3 mm or greater were detected by preoperative multi-detector row computed tomography images, though only 6% of branches with diameters of 2 mm or less could be visualized. There was a positive linear correlation between left ventricular volumes determined by multi-detector row computed tomography and those calculated from cine angiography. Multi-detector row computed tomography clearly visualized coronary bypass grafts and aortic arterial branches, providing detailed vascular images. Atheromatous degeneration assessed by multi-detector row computed tomography was equivalent with intraoperative findings in more than 70% of cases. Left ventricular volumes measured by multi-detector row computed tomography correlated closely with those determined by cine-angiography. Multidetector row computed tomography is an efficient and promising modality in cardiovascular surgery. (author)

  12. CT findings in patients with cerebral palsy

    International Nuclear Information System (INIS)

    Konno, Kimiichi

    1982-01-01

    Clinical findings and CT findings in 73 cases of cerebral palsy were studied. The causes of cerebral palsy were presumed to be as follows: abnormal cerebral development (36%), asphyxial delivery (34%), and immature delivery (19%), etc. CT findings were abnormal in 58% of the 73 cases, 83% of the spastic tetraplegia patients and all of the spastic hemiplegia patients showed abnormal CT findings. All the patients with spastic monoplegia presented normal CT findings. In 75% of the spastic hemiplegia cases, the CT abnormalities were due to cerebral parenchymal abnormality such as porencephaly and regional low absorption. In cases of spastic tetraplegia, cerebral parenchymal abnormality was found only in 10%. Cortical atrophy was found only in 15 of the 73 cases, whereas central atrophy was found in 36 cases. (Ueda, J.)

  13. Multi-detector thoracic CT findings in cerebro-costo-mandibular syndrome: rib gaps and failure of costo-vertebral separation

    Energy Technology Data Exchange (ETDEWEB)

    Watson, Tom Anthony; Arthurs, Owen John; Calder, Alistair Duncan [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); Muthialu, Nagarajan [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Cardiothoracic surgery, London (United Kingdom)

    2014-02-15

    Cerebro-costo-mandibular syndrome (CCMS) describes a triad of mandibular hypoplasia, brain dysfunction and posterior rib defects (''rib gaps''). We present the CT imaging for a 2-year-old girl with CCMS that highlights the rib gap defects and shows absent transverse processes with abnormal fusion of the ribs directly to the vertebral bodies. We argue that this is likely to relate to abnormal lateral sclerotome development in embryology, with the failure of normal costo-vertebral junctions compounding impaired thoracic function. The case also highlights the use of CT for specific indications in skeletal dysplasia. (orig.)

  14. Multi-detector thoracic CT findings in cerebro-costo-mandibular syndrome: rib gaps and failure of costo-vertebral separation

    International Nuclear Information System (INIS)

    Watson, Tom Anthony; Arthurs, Owen John; Calder, Alistair Duncan; Muthialu, Nagarajan

    2014-01-01

    Cerebro-costo-mandibular syndrome (CCMS) describes a triad of mandibular hypoplasia, brain dysfunction and posterior rib defects (''rib gaps''). We present the CT imaging for a 2-year-old girl with CCMS that highlights the rib gap defects and shows absent transverse processes with abnormal fusion of the ribs directly to the vertebral bodies. We argue that this is likely to relate to abnormal lateral sclerotome development in embryology, with the failure of normal costo-vertebral junctions compounding impaired thoracic function. The case also highlights the use of CT for specific indications in skeletal dysplasia. (orig.)

  15. CT findings of renal abscess

    International Nuclear Information System (INIS)

    Lee, Myung Jun; Kim, Mi Young; Woo, Jung Ju; Kim, Ho Kyun; Kim, Won Hong; Jeon, Jeong Dong; Jeon, Woo Ki; Han, Chang Yul

    1996-01-01

    The purpose of this study is to determine characteristic CT findings in renal abscess. Twenty cases of renal abscess were retrospectively analyzed for CT findings relating to the shape and extent of the abscess, change of nephrogram, peripheral rim enhancement, wedge-shaped enhancement on delayed scans, enlargement of the kidney involved and associated findings. Seven patients had a renal abscess at the right kidney, nine at the lift kidney and two bilaterally. The abscesses were round in 18 cases and finger-like in two. Rim enhancement around renal abscess was seen in four cases (20%). Changes in the nephrogram around the abscess were seen in 12 cases (60%). In all six patients who had undergone delayed postcontrast scans, wedge-shaped enhancement was shown around the abscess (100%). In the observation of the extent of renal abscesses, 14 cases were within the kidney, six cases extended the beyond renal capsule, and two were loculated in the renal fascia itself. Renal enlargement was seen in nine cases (45%). These results suggest that CT findings such as delayed wedge-shaped enhancement, change of nephrogram, peripheral rim enhancement, renal enlargement, and associated findings are valuable for diagnosis, and that CT also gives information concerning the extent, evolution and complication of a renal abscess

  16. Multi-detector row CT of the kidney: Optimizing scan delays for bolus tracking techniques of arterial, corticomedullary, and nephrographic phases

    Energy Technology Data Exchange (ETDEWEB)

    Goshima, Satoshi [Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Kanematsu, Masayuki [Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Department of Radiology Services, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Nishibori, Hironori; Kondo, Hiroshi; Tsuge, Yusuke [Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Yokoyama, Ryujiro; Miyoshi, Toshiharu [Department of Radiology Services, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Onozuka, Minoru [Department of Physiology and Neuroscience, Kanagawa Dental College, Yokosuka, Kanagawa (Japan); Shiratori, Yoshimune [Department of Medical Informatics, Gifu University School of Medicine, Gifu (Japan); Moriyama, Noriyuki [Department of Diagnostic Radiology, National Cancer Center Hospital, Tsukiji, Chuo-Ku, Tokyo (Japan); Bae, Kyongtae T. [Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO (United States)

    2007-09-15

    Purpose: To determine optimal scan delays for renal arterial-, corticomedullary-, and nephrographic-phase imaging with multi-detector row computed tomography (MDCT) of the kidney using a bolus-tracking technique. Methods and materials: One hundred and twenty-eight patients underwent three-phase CT scan of the kidney with eight-row MDCT after receiving 2 mL/kg of 300 mg I/mL contrast medium at 4 mL/s. Patients were prospectively randomized into three groups with different scan delays for the three scan phases (arterial, corticomedullary, and nephrographic) after bolus-tracking triggered at 50 HU of aortic contrast enhancement: group 1 (5, 20, 45 s); group 2 (10, 25, 50 s); and group 3 (15, 30, 55 s). Mean CT values (HU) of the abdominal aorta, renal artery, renal vein, renal cortex, and renal medulla were measured; increases in CT values pre- to post-contrast were assessed as contrast enhancement. Renal artery-to-vein and renal cortex-to-medulla contrast differences were also assessed. Qualitative analysis was also performed. Results: Mean renal artery enhancement was 240-288 HU at 5-15 s after the trigger and peaked at 10 s (P < .001). Mean renal cortical enhancement was 195-217 HU at 10-30 s and peaked at 25 s (P < .01). Contrast enhancement in the renal medulla increased gradually and reached mean 145 HU at 55 s. Cortex-to-medulla contrast difference was high (110-140 HU) at 5-30 s and decreased below 30 HU at 45 s after the trigger. Renal artery-to-vein contrast difference was high (121-125 HU) at 5-10 s. Qualitative results correlated well with quantitative results. Conclusion: For the injection protocol used in this study, optimal scan delays after the bolus-tracking trigger were 5-10 s for renal arterial, 15-25 s for corticomedullary, and 50-55 s for nephrographic phases.

  17. A Detector for Combined SPECT/CT. Final Technical Report

    International Nuclear Information System (INIS)

    Vivek Nagarkar

    2006-01-01

    The goal of the Phase I research was to demonstrate the feasibility of developing a high performance SPECT/CT detector module based on a combination of microcolumnar CsI(Tl) scintillator coupled to an EMCCD readout. We are very pleased to report that our Phase I research has demonstrated the technical feasibility of our approach with a very high degree of success. Specifically, we were able to implement a back-thinned EMCCD with a fiberoptic window which was successfully used to demonstrate the feasibility of near simultaneous radionuclide/CT using the proposed concept. Although significantly limited in imaging area (24 x 24 mm 2 ) and pixel resolution (512 x 512), this prototype has shown exceptional capabilities such as a single optical photon sensitivity, very low noise, an intrinsic resolution of 64 (micro)m for radionuclide imaging, and a resolution in excess of 10 lp/mm for x-ray imaging. Furthermore, the combination of newly developed, thick, microcolumnar CsI and an EMCCD has shown to be capable of operating in a photon counting mode, and that the position and energy information obtained from these data can be used to improve resolution in radionuclide imaging. Finally, the prototype system has successfully been employed for near simultaneous SPECT/CT imaging using both, 125 I and 99m Tc radioisotopes. The tomographic reconstruction data obtained using a mouse heart phantom and other phantoms clearly demonstrate the feasibility and efficacy of the detector in small animal research. The following were the objectives specified in the Phase I proposal: (1) In consultation with Professor Hasegawa, develop specifications for the Phase I/Phase II prototype detector; (2) Modify current vapor deposition protocols to fabricate ∼2 mm thick microcolumnar CsI(Tl) scintillators with excellent columnar structure, high light yield, and high spatial resolution; (3) Perform detailed characterization of the film morphology, light output, and spatial resolution, and use

  18. CT findings of focal organizing pneumonia: correlation with pathologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yang Soo; Kim, Young Goo; Park, Un Sup [College of Medicine, Chungang University, Seoul (Korea, Republic of)

    1994-11-15

    To evaluate the CT findings of focal organizing pneumonia and to correlate them with pathologic findings to help differentiating from lung cancer. We evaluated radiologic and pathologic findings of five patients with solitary pulmonary nodule which were confirmed as focal organizing pneumonia pathologically. On CT scan, focal organizing pneumonia had irregular margin contacting the pleura in all five cases. The shape of the nodules were spherical to wedge or elliptical and the size from 3.5cm to 5.5cm(average 4.2 cm) in largest diameter. On postcontrast CT scan, all nodules showed enhancement and four cases showed central low density components. Two nodules contained air within the nodule. In four cases, pleural changes such as effusion and/or focal thickening were noted. No lymphadenopathy was found in all cases. Pathologically, the enhancing portion on CT showed findings of organizing pneumonia such as granulation tissue with fibroblast proliferation in alveolar space and interstitial thickening. The central low density areas on CT were due to ischemic necrosis, abscess and exudate, transudate and infiltration of foamy histiocyte. The possibility of focal organizing pneumonia should be considered when peripherally located solitary pulmonary nodule had enhancing component with no combined lymphadenopathy on CT scan.

  19. CT findings of focal organizing pneumonia: correlation with pathologic findings

    International Nuclear Information System (INIS)

    Kim, Yang Soo; Kim, Young Goo; Park, Un Sup

    1994-01-01

    To evaluate the CT findings of focal organizing pneumonia and to correlate them with pathologic findings to help differentiating from lung cancer. We evaluated radiologic and pathologic findings of five patients with solitary pulmonary nodule which were confirmed as focal organizing pneumonia pathologically. On CT scan, focal organizing pneumonia had irregular margin contacting the pleura in all five cases. The shape of the nodules were spherical to wedge or elliptical and the size from 3.5cm to 5.5cm(average 4.2 cm) in largest diameter. On postcontrast CT scan, all nodules showed enhancement and four cases showed central low density components. Two nodules contained air within the nodule. In four cases, pleural changes such as effusion and/or focal thickening were noted. No lymphadenopathy was found in all cases. Pathologically, the enhancing portion on CT showed findings of organizing pneumonia such as granulation tissue with fibroblast proliferation in alveolar space and interstitial thickening. The central low density areas on CT were due to ischemic necrosis, abscess and exudate, transudate and infiltration of foamy histiocyte. The possibility of focal organizing pneumonia should be considered when peripherally located solitary pulmonary nodule had enhancing component with no combined lymphadenopathy on CT scan

  20. Usefulness of multi-plane dynamic subtraction CT (MPDS-CT) for intracranial high density lesions

    Energy Technology Data Exchange (ETDEWEB)

    Takagi, Ryo; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan)

    1996-02-01

    We present a new CT technique using the high speed CT scanner in detection and evaluation of temporal and spatial contrast enhancement of intracranial high density lesions. A multi-plane dynamic subtraction CT (MPDS-CT) was performed in 21 patients with intracranial high density lesions. These lesions consisted of 10 brain tumors, 7 intracerebral hemorrhages and 4 vascular malformations (2 untreated, 2 post-embolization). Baseline study was first performed, and 5 sequential planes of covering total high density lesions were selected. After obtaining the 5 sequential CT images as mask images, three series of multi-plane dynamic CT were performed for the same 5 planes with an intravenous bolus injection of contrast medium. MPDS-CT images were reconstructed by subtracting dynamic CT images from the mask ones. MPDS-CT were compared with conventional contrast-enhanced CT. MPDS-CT images showed the definite contrast enhancement of high density brain tumors and vascular malformations which were not clearly identified on conventional contrast-enhanced CT images because of calcified or hemorrhagic lesions and embolic materials, enabling us to eliminate enhanced abnormalities with non-enhanced areas such as unusual intracerebral hemorrhages. MPDS-CT will provide us further accurate and objective information and will be greatly helpful for interpreting pathophysiologic condition. (author).

  1. Half-dose non-contrast CT in the investigation of urolithiasis: image quality improvement with third-generation integrated circuit CT detectors.

    Science.gov (United States)

    Wang, Jun; Kang, Tony; Arepalli, Chesnal; Barrett, Sarah; O'Connell, Tim; Louis, Luck; Nicolaou, Savvakis; McLaughlin, Patrick

    2015-06-01

    The objective of this study is to establish the effect of third-generation integrated circuit (IC) CT detector on objective image quality in full- and half-dose non-contrast CT of the urinary tract. 51 consecutive patients with acute renal colic underwent non-contrast CT of the urinary tract using a 128-slice dual-source CT before (n = 24) and after (n = 27) the installation of third-generation IC detectors. Half-dose images were generated using projections from detector A using the dual-source RAW data. Objective image noise in the liver, spleen, right renal cortex, and right psoas muscle was compared between DC and IC cohorts for full-dose and half-dose images reconstructed with FBP and IR algorithms using 1 cm(2) regions of interest. Presence and size of obstructing ureteric calculi were also compared for full-dose and half-dose reconstructions using DC and IC detectors. No statistical difference in age and lateral body size was found between patients in the IC and DC cohorts. Radiation dose, as measured by size-specific dose estimates, did not differ significantly either between the two cohorts (10.02 ± 4.54 mGy IC vs. 12.28 ± 7.03 mGy DC). At full dose, objective image noise was not significantly lower in the IC cohort as compared to the DC cohort for the liver, spleen, and right psoas muscle. At half dose, objective image noise was lower in the IC cohort as compared to DC cohort at the liver (21.32 IC vs. 24.99 DC, 14.7% decrease, p 0.05 for all comparisons). Third-generation IC detectors result in lower objective image noise at full- and half-radiation dose levels as compared with traditional DC detectors. The magnitude of noise reduction was greater at half-radiation dose indicating that the benefits of using novel IC detectors are greater in low and ultra-low-dose CT imaging.

  2. Improved quantitation and reproducibility in multi-PET/CT lung studies by combining CT information.

    Science.gov (United States)

    Holman, Beverley F; Cuplov, Vesna; Millner, Lynn; Endozo, Raymond; Maher, Toby M; Groves, Ashley M; Hutton, Brian F; Thielemans, Kris

    2018-06-05

    Matched attenuation maps are vital for obtaining accurate and reproducible kinetic and static parameter estimates from PET data. With increased interest in PET/CT imaging of diffuse lung diseases for assessing disease progression and treatment effectiveness, understanding the extent of the effect of respiratory motion and establishing methods for correction are becoming more important. In a previous study, we have shown that using the wrong attenuation map leads to large errors due to density mismatches in the lung, especially in dynamic PET scans. Here, we extend this work to the case where the study is sub-divided into several scans, e.g. for patient comfort, each with its own CT (cine-CT and 'snap shot' CT). A method to combine multi-CT information into a combined-CT has then been developed, which averages the CT information from each study section to produce composite CT images with the lung density more representative of that in the PET data. This combined-CT was applied to nine patients with idiopathic pulmonary fibrosis, imaged with dynamic 18 F-FDG PET/CT to determine the improvement in the precision of the parameter estimates. Using XCAT simulations, errors in the influx rate constant were found to be as high as 60% in multi-PET/CT studies. Analysis of patient data identified displacements between study sections in the time activity curves, which led to an average standard error in the estimates of the influx rate constant of 53% with conventional methods. This reduced to within 5% after use of combined-CTs for attenuation correction of the study sections. Use of combined-CTs to reconstruct the sections of a multi-PET/CT study, as opposed to using the individually acquired CTs at each study stage, produces more precise parameter estimates and may improve discrimination between diseased and normal lung.

  3. Multi-Grid detector for neutron spectroscopy: results obtained on time-of-flight spectrometer CNCS

    Science.gov (United States)

    Anastasopoulos, M.; Bebb, R.; Berry, K.; Birch, J.; Bryś, T.; Buffet, J.-C.; Clergeau, J.-F.; Deen, P. P.; Ehlers, G.; van Esch, P.; Everett, S. M.; Guerard, B.; Hall-Wilton, R.; Herwig, K.; Hultman, L.; Höglund, C.; Iruretagoiena, I.; Issa, F.; Jensen, J.; Khaplanov, A.; Kirstein, O.; Lopez Higuera, I.; Piscitelli, F.; Robinson, L.; Schmidt, S.; Stefanescu, I.

    2017-04-01

    The Multi-Grid detector technology has evolved from the proof-of-principle and characterisation stages. Here we report on the performance of the Multi-Grid detector, the MG.CNCS prototype, which has been installed and tested at the Cold Neutron Chopper Spectrometer, CNCS at SNS. This has allowed a side-by-side comparison to the performance of 3He detectors on an operational instrument. The demonstrator has an active area of 0.2 m2. It is specifically tailored to the specifications of CNCS. The detector was installed in June 2016 and has operated since then, collecting neutron scattering data in parallel to the He-3 detectors of CNCS. In this paper, we present a comprehensive analysis of this data, in particular on instrument energy resolution, rate capability, background and relative efficiency. Stability, gamma-ray and fast neutron sensitivity have also been investigated. The effect of scattering in the detector components has been measured and provides input to comparison for Monte Carlo simulations. All data is presented in comparison to that measured by the 3He detectors simultaneously, showing that all features recorded by one detector are also recorded by the other. The energy resolution matches closely. We find that the Multi-Grid is able to match the data collected by 3He, and see an indication of a considerable advantage in the count rate capability. Based on these results, we are confident that the Multi-Grid detector will be capable of producing high quality scientific data on chopper spectrometers utilising the unprecedented neutron flux of the ESS.

  4. CT findings of early acute cerebral infarction

    International Nuclear Information System (INIS)

    Kim, Tae Hoon; Choi, Woo Suk; Ryu, Kyung Nam

    1992-01-01

    The CT findings of the acute cerebral infarction are well known. However the CT findings of early stroke within 24 hours of the onset have not been sufficiently reported. The purpose of this study is to evaluate early acute cerebral infarction on CT within 24 hours after ictus. The early and accurate CT diagnosis could lead to the appropriate therapy and improved outcome of the patients. Authors retrospectively analyzed 16 patients with early acute cerebral infarction. Acute cerebral infarction was confirmed by follow-up CT in 11 patients, SPECT in 4 patients, and MRI in 1 patient. The CT findings of early acute cerebral infarction include effacement of cortical sulci or cistern (n = 16, 100%), hyperattenuation of MCA (n = 3), obscuration of lentiform nucleus (n = 6), loss of insular ribbon (n = 6) and subtle low density in hemisphere (n = 5). The most frequent finding was effacement of cortical sulci in our study, and it was thought to be the most important sign of early acute cerebral infarction

  5. CT findings of early acute cerebral infarction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Hoon; Choi, Woo Suk; Ryu, Kyung Nam [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1992-11-15

    The CT findings of the acute cerebral infarction are well known. However the CT findings of early stroke within 24 hours of the onset have not been sufficiently reported. The purpose of this study is to evaluate early acute cerebral infarction on CT within 24 hours after ictus. The early and accurate CT diagnosis could lead to the appropriate therapy and improved outcome of the patients. Authors retrospectively analyzed 16 patients with early acute cerebral infarction. Acute cerebral infarction was confirmed by follow-up CT in 11 patients, SPECT in 4 patients, and MRI in 1 patient. The CT findings of early acute cerebral infarction include effacement of cortical sulci or cistern (n = 16, 100%), hyperattenuation of MCA (n = 3), obscuration of lentiform nucleus (n = 6), loss of insular ribbon (n = 6) and subtle low density in hemisphere (n = 5). The most frequent finding was effacement of cortical sulci in our study, and it was thought to be the most important sign of early acute cerebral infarction.

  6. Technical principles of dual source CT

    International Nuclear Information System (INIS)

    Petersilka, Martin; Bruder, Herbert; Krauss, Bernhard; Stierstorfer, Karl; Flohr, Thomas G.

    2008-01-01

    During the past years, multi-detector row CT (MDCT) has evolved into clinical practice with a rapid increase of the number of detector slices. Today's 64 slice CT systems allow whole-body examinations with sub-millimeter resolution in short scan times. As an alternative to adding even more detector slices, we describe the system concept and design of a CT scanner with two X-ray tubes and two detectors (mounted on a CT gantry with a mechanical offset of 90 deg.) that has the potential to overcome limitations of conventional MDCT systems, such as temporal resolution for cardiac imaging. A dual source CT (DSCT) scanner provides temporal resolution equivalent to a quarter of the gantry rotation time, independent of the patient's heart rate (83 ms at 0.33 s rotation time). In addition to the benefits for cardiac scanning, it allows to go beyond conventional CT imaging by obtaining dual energy information if the two tubes are operated at different voltages. Furthermore, we discuss how both acquisition systems can be used to add the power reserve of two X-ray tubes for long scan ranges and obese patients. Finally, future advances of DSCT are highlighted

  7. Simultaneous CT and SPECT tomography using CZT detectors

    Science.gov (United States)

    Paulus, Michael J.; Sari-Sarraf, Hamed; Simpson, Michael L.; Britton, Jr., Charles L.

    2002-01-01

    A method for simultaneous transmission x-ray computed tomography (CT) and single photon emission tomography (SPECT) comprises the steps of: injecting a subject with a tracer compound tagged with a .gamma.-ray emitting nuclide; directing an x-ray source toward the subject; rotating the x-ray source around the subject; emitting x-rays during the rotating step; rotating a cadmium zinc telluride (CZT) two-sided detector on an opposite side of the subject from the source; simultaneously detecting the position and energy of each pulsed x-ray and each emitted .gamma.-ray captured by the CZT detector; recording data for each position and each energy of each the captured x-ray and .gamma.-ray; and, creating CT and SPECT images from the recorded data. The transmitted energy levels of the x-rays lower are biased lower than energy levels of the .gamma.-rays. The x-ray source is operated in a continuous mode. The method can be implemented at ambient temperatures.

  8. Pseudomembranous colitis: CT findings in children

    International Nuclear Information System (INIS)

    Blickman, J.G.; Boland, G.W.L.; Cleveland, R.H.; Bramson, R.T.; Lee, M.J.

    1995-01-01

    A spectrum of nodular haustral thickening and an 'accordion' pattern have been reported as specific features of pseudomembranous colitis (PMC) in adults. A retrospective review of nine patients with PMC was performed to assess whether this spectrum of CT findings also occurred in children. In four girls and five boys, CT scans were performed within 3 days of a positive stool toxin assay for Clostridium difficile. Documented CT abnormalities included nodular haustral thickening, the 'accordion' pattern, colonic wall thickening, ascites, and pericolonic edema. These results were then correlated as to their impact on the clinical outcome. Circumferential colon wall thickening was identified in 7/9 (78%) patients (mean thickening 14.5 mm). Nodular haustral thickening was identified in 4/9 (44%) and the 'accordion' pattern in 2/9 (22%). Other findings included pericolonic edema in 3/9 (33%) and ascites in 1/9 (11%). Wall thickening was confined to the left colon and rectum in 2/9 (22%), to the right colon in 2/9 (22%), and involved the whole colon in 3/9 (33%). Although CT findings associated with PMC in children may be suggestive for this diagnosis, CT is less specific than laboratory and clinical findings. (orig.)

  9. Pseudomembranous colitis: CT findings in children

    Energy Technology Data Exchange (ETDEWEB)

    Blickman, J.G. [Massachusetts General Hospital, Boston, MA (United States); Boland, G.W.L. [Massachusetts General Hospital, Boston, MA (United States); Cleveland, R.H. [The Children`s Hospital, Boston, MA (United States); Bramson, R.T. [Massachusetts General Hospital, Boston, MA (United States); Lee, M.J. [Massachusetts General Hospital, Boston, MA (United States)

    1995-11-01

    A spectrum of nodular haustral thickening and an `accordion` pattern have been reported as specific features of pseudomembranous colitis (PMC) in adults. A retrospective review of nine patients with PMC was performed to assess whether this spectrum of CT findings also occurred in children. In four girls and five boys, CT scans were performed within 3 days of a positive stool toxin assay for Clostridium difficile. Documented CT abnormalities included nodular haustral thickening, the `accordion` pattern, colonic wall thickening, ascites, and pericolonic edema. These results were then correlated as to their impact on the clinical outcome. Circumferential colon wall thickening was identified in 7/9 (78%) patients (mean thickening 14.5 mm). Nodular haustral thickening was identified in 4/9 (44%) and the `accordion` pattern in 2/9 (22%). Other findings included pericolonic edema in 3/9 (33%) and ascites in 1/9 (11%). Wall thickening was confined to the left colon and rectum in 2/9 (22%), to the right colon in 2/9 (22%), and involved the whole colon in 3/9 (33%). Although CT findings associated with PMC in children may be suggestive for this diagnosis, CT is less specific than laboratory and clinical findings. (orig.)

  10. Objective image characterization of a spectral CT scanner with dual-layer detector

    Science.gov (United States)

    Ozguner, Orhan; Dhanantwari, Amar; Halliburton, Sandra; Wen, Gezheng; Utrup, Steven; Jordan, David

    2018-01-01

    This work evaluated the performance of a detector-based spectral CT system by obtaining objective reference data, evaluating attenuation response of iodine and accuracy of iodine quantification, and comparing conventional CT and virtual monoenergetic images in three common phantoms. Scanning was performed using the hospital’s clinical adult body protocol. Modulation transfer function (MTF) was calculated for a tungsten wire and visual line pair targets were evaluated. Image noise power spectrum (NPS) and pixel standard deviation were calculated. MTF for monoenergetic images agreed with conventional images within 0.05 lp cm-1. NPS curves indicated that noise texture of 70 keV monoenergetic images is similar to conventional images. Standard deviation measurements showed monoenergetic images have lower noise except at 40 keV. Mean CT number and CNR agreed with conventional images at 75 keV. Measured iodine concentration agreed with true concentration within 6% for inserts at the center of the phantom. Performance of monoenergetic images at detector based spectral CT is the same as, or better than, that of conventional images. Spectral acquisition and reconstruction with a detector based platform represents the physical behaviour of iodine as expected and accurately quantifies the material concentration.

  11. CT findings of chronic eosinophilic pneumonia

    International Nuclear Information System (INIS)

    Kigami, Yusuke; Nishizawa, Sadahiko; Kuroda, Yasumasa

    1992-01-01

    CT scans in 11 cases of chronic eosinophilic pneumonia (CEP) were reviewed. Peripheral dense opacities suggesting air-space consolidation were the most peculiar findings seen in 9 patients on CT, but 7 on chest radiographs. Five patients showed broad plate-like opacities parallel to the pleura, which were the results of resolution from the periphery of the consolidation. Diffuse interstitial opacities suggesting alveolitis were the predominant finding in 3 patients, one of which also had peripheral air-space consolidation. Follow-up CT showed no residual abnormality except one who had DIP concomitant with CEP. CT scans are useful tool for both diagnosis and follow-up of CEP. (author)

  12. Musculoskeletal wide detector CT: Principles, techniques and applications in clinical practice and research

    International Nuclear Information System (INIS)

    Gondim Teixeira, Pedro Augusto; Gervaise, Alban; Louis, Matthias; Lecocq, Sophie; Raymond, Ariane; Aptel, Sabine; Blum, Alain

    2015-01-01

    Highlights: • Wide area-detector CT availability is growing steadily. • Advanced techniques such as Dynamic CT, Perfusion CT and dual energy can be used in clinical practice. • Optimal acquisition protocol is needed to increase diagnostic performance and limit dose exposure. • Guidelines for data acquisition and interpretation may increase diagnostic performance and reproducibility. - Abstract: A progressive increase in the detector width in CT scanners has meant that advanced techniques such as dynamic, perfusion and dual-energy CT are now at the radiologist's disposal. Although these techniques may be important for the diagnosis of various musculoskeletal diseases, data acquisition and interpretation can be challenging. This article offers a practical guide for the use of these tools including acquisition protocol, post-processing options and data interpretation based on 7 years of clinical experience in a tertiary university hospital

  13. Solitary pulmonary nodules: Comparison of dynamic first-pass contrast-enhanced perfusion area-detector CT, dynamic first-pass contrast-enhanced MR imaging, and FDG PET/CT.

    Science.gov (United States)

    Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Seki, Shinichiro; Tsubakimoto, Maho; Fujisawa, Yasuko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

    2015-02-01

    To prospectively compare the capabilities of dynamic perfusion area-detector computed tomography (CT), dynamic magnetic resonance (MR) imaging, and positron emission tomography (PET) combined with CT (PET/CT) with use of fluorine 18 fluorodeoxyglucose (FDG) for the diagnosis of solitary pulmonary nodules. The institutional review board approved this study, and written informed consent was obtained from each subject. A total of 198 consecutive patients with 218 nodules prospectively underwent dynamic perfusion area-detector CT, dynamic MR imaging, FDG PET/CT, and microbacterial and/or pathologic examinations. Nodules were classified into three groups: malignant nodules (n = 133) and benign nodules with low (n = 53) or high (n = 32) biologic activity. Total perfusion was determined with dual-input maximum slope models at area-detector CT, maximum and slope of enhancement ratio at MR imaging, and maximum standardized uptake value (SUVmax) at PET/CT. Next, all indexes for malignant and benign nodules were compared with the Tukey honest significant difference test. Then, receiver operating characteristic analysis was performed for each index. Finally, sensitivity, specificity, and accuracy were compared with the McNemar test. All indexes showed significant differences between malignant nodules and benign nodules with low biologic activity (P Dynamic perfusion area-detector CT is more specific and accurate than dynamic MR imaging and FDG PET/CT in the diagnosis of solitary pulmonary nodules in routine clinical practice. © RSNA, 2014.

  14. EEG and CT findings of infant partial seizures

    International Nuclear Information System (INIS)

    Kajitani, Takashi; Kumanomido, Yoshiaki; Nakamura, Makoto; Ueoka, Kiyotaka

    1981-01-01

    Examination of EEG and cranial CT were performed in 19 cases of partial seizures with elementary symptomatology (PSES), 6 cases of partial seizures with complex symptomatology (PSCS), and 17 cases of benign focal pilepsy of childhood with Rolandic spikes (BFECRS). The results were as follows. 1) In 16 of 19 cases of PSES (84%), various abnormal CT findings such as localized cerebral atrophy (7 cases), localized cerebral atrophy complicated with porencephaly (4 cases), porencephaly alone (2 cases), and diffuse cerebral atrophy (3 cases) were found. 2) Of 6 cases of PSCS localized cerebral atrophy was found in 3 cases, porencephaly in one case, and localized calcification in one case. Normal CT findings were obtained in one case. 3) In comparison of EEG findings with CT findings in 25 cases of partial seizures CT findings correlated with the basic waves rather than the paroxysmal ones. 4) The fact that CT findings in patients with BFECRS were mostly normal suggests the functional origin of the seizures. 5) CT was valuable in partial seizures for detecting underlying disorders and predicting the prognosis. (Ueda, J.)

  15. CT findings of pancreatic carcinoma. Evaluation with the combined method of early enhancement CT and high dose enhancement CT

    International Nuclear Information System (INIS)

    Itoh, Shigeki; Endo, Tokiko; Isomura, Takayuki; Ishigaki, Takeo; Ikeda, Mitsuru; Senda, Kouhei.

    1995-01-01

    Computed tomographic (CT) findings of pancreatic ductal adenocarcinoma were studied with the combined method of early enhancement CT and high dose enhancement CT in 72 carcinomas. Common Findings were change in pancreatic contour, abnormal attenuation in a tumor and dilatation of the main pancreatic duct. The incidence of abnormal attenuation and dilatation of the main pancreatic duct and bile duct was constant regardless of tumor size. The finding of hypoattenuation at early enhancement CT was most useful for demonstrating a carcinoma. However, this finding was negative in ten cases, five of which showed inhomogenous hyperattenuation at high dose enhancement CT. The detection of change in pancreatic contour and dilatation of the main pancreatic duct was most frequent at high dose enhancement CT. The finding of change in pancreatic contour and/or abnormal attenuation in a tumor could be detected in 47 cases at plain CT, 66 at early enhancement CT and 65 at high dose enhancement CT. Since the four cases in which neither finding was detected by any CT method showed dilatated main pancreatic duct, there was no case without abnormal CT findings. This combined CT method will be a reliable diagnostic technique in the imaging of pancreatic carcinoma. (author)

  16. Multi-sensor radiation detector system

    International Nuclear Information System (INIS)

    Foster, R.G.; Cyboron, R.D.

    1975-01-01

    The invention is a multi-sensor radiation detection system including a self-powered detector and an ion or fission chamber, preferably joined as a unitary structure, for removable insertion into a nuclear reactor. The detector and chamber are connected electrically in parallel, requiring but two conductors extending out of the reactor to external electrical circuitry which includes a load impedance, a voltage source, and switch means. The switch means are employed to alternately connect the detector and chamber either with th load impedance or with the load impedance and the voltage source. In the former orientation, current through the load impedance indicates flux intensity at the self-powered detector and in the latter orientation, the current indicates flux intensity at the detector and fission chamber, though almost all of the current is contributed by the fission chamber. (auth)

  17. Abdominal aspergillosis: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Yeom, Suk Keu, E-mail: pagoda20@hanmail.net [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Kim, Hye Jin, E-mail: kimhyejin@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Byun, Jae Ho, E-mail: jhbyun@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Kim, Ah Young, E-mail: aykim@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Lee, Moon-Gyu, E-mail: mglee@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Ha, Hyun Kwon, E-mail: hkha@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of)

    2011-03-15

    Objective: In order to retrospectively evaluate the CT findings of abdominal aspergillosis in immunocompromised patients. Materials and methods: CT scans were reviewed with regard to the sites, number, morphologic appearance, attenuation, and the contrast enhancement patterns of the lesions in six patients (5 women, 1 man; mean age, 43.4 years; range, 23-59 years) with pathologically proved abdominal aspergillosis by two gastrointestinal radiologists in consensus. Medical records were also reviewed to determine each patient's clinical status and outcome. Results: All patients were immunocompromised state: 4 patients received immunosuppressive therapy for solid organ transplantation and 2 patients received chemotherapy for acute myeloid leukemia. Aspergillosis involved blood vessels (n = 3), liver (n = 2), spleen (n = 2), gastrointestinal tract (n = 2), native kidney (n = 1), transplanted kidney (n = 1), peritoneum (n = 1), and retroperitoneum (n = 1). CT demonstrated solid organ or bowel infarction or perforation secondary to vascular thrombosis or pseudoaneurysm, multiple low-attenuating lesions of solid organs presenting as abscesses, concentric bowel wall thickening mimicking typhlitis, or diffuse or nodular infiltration of the peritoneum and retroperitoneum. Conclusion: Familiarity with findings commonly presenting as angioinvasive features or abscesses on CT, may facilitate the diagnosis of rare and fatal abdominal aspergillosis.

  18. CT findings in epileptic children

    International Nuclear Information System (INIS)

    Koide, Nobuo; Kimura, Shigeru; Watanabe, Jun; Haneda, Satoshi; Takebe, Yukinao

    1981-01-01

    CT findings in 43 children with generalized seizures (grand mal seizures) (GM group) and in 50 children with partial seizures (P group), classified according to clinical seizure type, were studied. 1) CT abnormalities were demonstrated in 19% (8/43) in GM group and in 40% (20/50) in P group, including localized CT abnormalities in 9.3% (4/43) and in 34% (17/50) respectively. CT abnormalities were found more frequently in cases with abnormal past histories and/or mental defects (MD) than in those without them. 2) In P group, localized CT abnormalities and generalized brain atrophy were observed in 13 and 7 cases respectively. In 40 cases with focal epileptic discharges (FED) in EEG, localized CT abnormalities were demonstrated in 23% (9/40). The sites of localized CT abnormalities corresponded in 73% (11/15) to the sites of focal suppression in EEG (i.e., slowing, low amplitude and lazy pattern) regardless of FED. 3) The bicaudate cerebro-ventricular index (B-CVI) in 19 cases in the normal control group over 2 years of age was 10.0 +- 1.2 (mean +- SD). Ventricular narrowing (VN), with B-CVI less than 8.2 (mean - 1.5 SD), was observed in 5, 17 and 27% in control, GM and P groups respectively, indicating more frequently in epileptic children than in normal controls. Seizures were well controlled in 85% (11/13) in VN group and in 70% (26/36) in normal ventricular group. Brain atrophy in CT findings to inspection was ascertained in all cases by measuring B-CVI. (author)

  19. A new cone-beam X-ray CT system with a reduced size planar detector

    International Nuclear Information System (INIS)

    Li Liang; Chen Zhiqiang; Zhang Li; Xing Yuxiang; Kang Kejun

    2006-01-01

    In a traditional cone-beam CT system, the cost of product and computation is very high. The authors propose a transversely truncated cone-beam X-ray CT system with a reduced size detector positioned off-center, in which X-ray beams only cover half of the object. The reduced detector size cuts the cost and the X-ray dose of the CT system. The existing CT reconstruction algorithms are not directly applicable in this new CT system. Hence, the authors develop a BPF-type direct backprojection algorithm. Different from the traditional rebinding methods, our algorithm directly backprojects the pretreated projection data without rebinding. This makes the algorithm compact and computationally more efficient. Finally, some numerical simulations and practical experiments are done to validate the proposed algorithm. (authors)

  20. CT findings of pulmonary hypertension

    International Nuclear Information System (INIS)

    Inoue, Yukio; Tanimoto, Akihiro; Sato, Toru; Kuribayashi, Sachio

    2006-01-01

    For the treatment for pulmonary hypertension (PH), the differential diagnosis of its causal diseases is essential. To determine whether X-ray CT is useful for differentiating PH, we reviewed CT findings of 53 patients (18 men and 35 women, mean age of 44.9) given a diagnosis of PH, consisting of 25 with primary pulmonary hypertension (PPH), 18 with chronic pulmonary embolism (cPE), 6 with Eisenmenger syndrome, 5 cases of collagen diseases, 2 of acute PE, and 1 of cor pulmonale. The intrapulmonary distribution of CT findings (ground glass opacity [GGO], mosaic attenuation, striation and/or infiltration, and interlobular septal thickening) were reviewed and scored on a 4-point scale (grade 0: no findings, 1: involving one third of the lung, 2: involving one-two thirds, and 3: diffuse distribution) by two radiologists who reached a consensus. PPH showed preferentially diffuse distribution of GGO as compared with cPE (p<0.05). However, there was no apparent relationship between the pulmonary vascular resistance and the distribution of GGO in PPH cases. The mosaic attenuation pattern was more frequent in cPE (43%) than PPH (12%; p<0.05). Striation and/or infiltration was observed in 36% of cPE, but only 4% of PPH. Interlobular septal thickening was seen in 16% of PPH, and 0% in cPE. Evaluation of CT findings is useful to differentiate PH. (author)

  1. Optimization of Proton CT Detector System and Image Reconstruction Algorithm for On-Line Proton Therapy.

    Directory of Open Access Journals (Sweden)

    Chae Young Lee

    Full Text Available The purposes of this study were to optimize a proton computed tomography system (pCT for proton range verification and to confirm the pCT image reconstruction algorithm based on projection images generated with optimized parameters. For this purpose, we developed a new pCT scanner using the Geometry and Tracking (GEANT 4.9.6 simulation toolkit. GEANT4 simulations were performed to optimize the geometric parameters representing the detector thickness and the distance between the detectors for pCT. The system consisted of four silicon strip detectors for particle tracking and a calorimeter to measure the residual energies of the individual protons. The optimized pCT system design was then adjusted to ensure that the solution to a CS-based convex optimization problem would converge to yield the desired pCT images after a reasonable number of iterative corrections. In particular, we used a total variation-based formulation that has been useful in exploiting prior knowledge about the minimal variations of proton attenuation characteristics in the human body. Examinations performed using our CS algorithm showed that high-quality pCT images could be reconstructed using sets of 72 projections within 20 iterations and without any streaks or noise, which can be caused by under-sampling and proton starvation. Moreover, the images yielded by this CS algorithm were found to be of higher quality than those obtained using other reconstruction algorithms. The optimized pCT scanner system demonstrated the potential to perform high-quality pCT during on-line image-guided proton therapy, without increasing the imaging dose, by applying our CS based proton CT reconstruction algorithm. Further, we make our optimized detector system and CS-based proton CT reconstruction algorithm potentially useful in on-line proton therapy.

  2. TH-CD-207B-05: Measurement of CT Bow-Tie Profiles Using a Linear Array Detector

    Energy Technology Data Exchange (ETDEWEB)

    Yang, K; Li, X; Liu, B [Massachusetts General Hospital, Boston, MA (United States)

    2016-06-15

    Purpose: To accurately measure CT bow-tie profiles from various manufacturers and to provide non-proprietary information for CT system modeling. Methods: A GOS-based linear detector (0.8 mm per pixel and 51.2 cm in length) with a fast data sampling speed (0.24 ms/sample) was used to measure the relative profiles of bow-tie filters from a collection of eight CT scanners by three different vendors, GE (LS Xtra, LS VCT, Discovery HD750), Siemens (Sensation 64, Edge, Flash, Force), and Philips (iBrilliance 256). The linear detector was first calibrated for its energy response within typical CT beam quality ranges and compared with an ion chamber and analytical modeling (SPECTRA and TASMIP). A geometrical calibration process was developed to determine key parameters including the distance from the focal spot to the linear detector, the angular increment of the gantry at each data sampling, the location of the central x-ray on the linear detector, and the angular response of the detector pixel. Measurements were performed under axial-scan modes for most representative bow-tie filters and kV selections from each scanner. Bow-tie profiles were determined by re-binning the measured rotational data with an angular accuracy of 0.1 degree using the calibrated geometrical parameters. Results: The linear detector demonstrated an energy response as a solid state detector, which is close to the CT imaging detector. The geometrical calibration was proven to be sufficiently accurate (< 1mm in error for distances >550 mm) and the bow-tie profiles measured from rotational mode matched closely to those from the gantry-stationary mode. Accurate profiles were determined for a total of 21 bow-tie filters and 83 filter/kV combinations from the abovementioned scanner models. Conclusion: A new improved approach of CT bow-tie measurement was proposed and accurate bow-tie profiles were provided for a broad list of CT scanner models.

  3. CT-findings in ARDS

    Energy Technology Data Exchange (ETDEWEB)

    Stark, P; Greene, R; Kott, M M; Hall, T; Vanderslice, L

    1987-08-01

    The CT features of 28 patients with ARDS are described. Diffuse lung consolidation, multifocal patchy involvement and lobar or segmental disease were observed. Large lung cysts as well as small cysts producing a 'swiss-cheese' appearance of the parenchyma, were detected. These findings were not regularly appreciated on chest radiographs. The overall mortality of our 28 patients was 72.7% (22 out 28). Patients with lung cysts showed a trend toward higher mortality (87.5% or 13 out 16). Other unexpected findings were basilar lung abscesses and an empyema. In 15 out of 28 patients, CT scans provided additional information, not obvious on bedside chest radiographs and led to a change in management in five patients.

  4. Studies on CT findings and operation findings for acute appendicitis in children

    International Nuclear Information System (INIS)

    Sakakibara, Kenichi; Andoh, Shigemitsu; Karamatsu, Syouji; Urakami, Toshihiko; Tsuji, Hideki; Kobayashi, Tohru; Okahira, Kihiro

    1995-01-01

    Pediatric CT findings of acute appendicitis were reviewed retrospectively. The subjects were 29 patients (15 boys and 14 girls with an average age of 8.2 years), consisting of 17 with necrotic, 8 with phlegmonous inflammatory, and 4 with catarrhal appendicitis. CT findings were compared with the degree of inflammation. CT revealed abscess in 64.7%, 12.5%, and 0% for necrotic, phlegmonous inflammatory, and catarrhal types, respectively, and 41.4% for all types. An enlarged appendicitis was shown on CT in 86.2% (25/29). Fecalithes were shown on CT in 67.7% (19/29), which was associated with necrotic and phlegmonous inflammatory types, but not with catarrhal type. The other CT findings included thickened paramesocolon of the right lower abdomen, undefined wall of the inner side of the cecum. Inflammation was relatively slight in cases of catarrhal appendicitis, Nine patients less than 5 years of age had phlegmonous inflammatory or necrotic appendicitis. CT allowed definitive diagnosis of appendicitis in 2 of 3 patients with necrotic type. Ct was considered to be very useful in the diagnosis of appendicitis. (N.K.)

  5. CT finding of emphysematous gastritis

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sang Won; Juhn, Jae Ryang; Cha, Seong Sook; Eun, Tchoong Kie; Chung, Duck Hwan [Inje Medical College Paik HospitalYonsei University College of Medicine, Seoul (Korea, Republic of)

    1988-12-15

    Emphysematous gastritis is a rare entity of infectious gastritis caused by gas-forming organisms and only 32 cases have been reported. CT is helpful in the diagnosis particularly in mild cases that there is only a small amount of gas. Typical CT findings of emphysematous gastritis are gas bubbles within the irregular thickened gastric wall and dilated stomach filled with secretions, debris and a large amount of gas. We report a case that was diagnosed by CT and operation.

  6. CT finding of emphysematous gastritis

    International Nuclear Information System (INIS)

    Ahn, Sang Won; Juhn, Jae Ryang; Cha, Seong Sook; Eun, Tchoong Kie; Chung, Duck Hwan

    1988-01-01

    Emphysematous gastritis is a rare entity of infectious gastritis caused by gas-forming organisms and only 32 cases have been reported. CT is helpful in the diagnosis particularly in mild cases that there is only a small amount of gas. Typical CT findings of emphysematous gastritis are gas bubbles within the irregular thickened gastric wall and dilated stomach filled with secretions, debris and a large amount of gas. We report a case that was diagnosed by CT and operation.

  7. CT findings of peritoneal carcinomatosis

    International Nuclear Information System (INIS)

    Kim, Eun Sook; Park, Mi Sook; Cho, On Koo; Koh, Byung Hee; Kim, Soon Yong

    1989-01-01

    CT findings in 137 patients with peritoneal cacinomatosis were reviewed to determine the CT signs of peritoneal malignancy. CT of the 20 liver cirrhosis and 17 tuberculous peritonitis were also reviewed to define the differential point between benign and malignant peritoneal change. The results were as follows. 1. The most common primary malignancy encountered in peritoneal carcinomatosis was stomach Ca.(50.4%), followed by pancreas Ca, hepatoma, colon Ca. and ovarian Ca. 2. Ascites was the most common CT feature of peritoneal malignancy, present in 99 cases (72.3%). The amount of ascites was voluminous, grade III in 70% of cases and showed high density ascites with average 23 Hounsfield units. 3. Greater omentum involvement was noted in 88 patients, peritoneum in 71 patients and mesentery in 65% patients. There was no correlation of the primary malignancy type with the incidence or pattern of the above mentioned site. 4. Bowel wall thickenings were observed in 51 patients, among which transverse colon was most frequently involved. 5. Mean attenuation value of ascites in liver cirrhosis was 10.7 HU, which was much lower than that of peritoneal carcinomatosis. 6. Even though intraperitoneal findings in Tbc. Peritonitis showed tendency of relatively small amount of ascites with more predominant mesenteric change, but, the findings of high density ascites, change of peritoneum and omentum etc. were very similar to those of peritoneal carcinomatosis. Therefore, based on only intraperitoneal change, differential diagnosis between them was difficult. 7. False negatives in CT diagnosis of peritoneal carcinomatosis occurred in 7 cases. There were tiny nodular changes in intraperitoneal cavity without ascites on operative findings

  8. Accuracy of 16-slice multi-detector CT to quantify the degree of coronary artery stenosis: Assessment of cross-sectional and longitudinal vessel reconstructions

    Energy Technology Data Exchange (ETDEWEB)

    Cury, Ricardo C. [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States)]. E-mail: rcury@partners.org; Ferencik, Maros [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Achenbach, Stephan [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Division of Cardiology, Massachusetts General Hospital, Boston, MA (United States); Department of Internal Medicine II, University of Erlangen (Germany); Pomerantsev, Eugene [Division of Cardiology, Massachusetts General Hospital, Boston, MA (United States); Nieman, Koen [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Moselewski, Fabian [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Division of Cardiology, Massachusetts General Hospital, Boston, MA (United States); Abbara, Suhny [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Jang, Ik-Kyung [Division of Cardiology, Massachusetts General Hospital, Boston, MA (United States); Brady, Thomas J. [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Hoffmann, Udo [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States)

    2006-03-15

    Background: Sixteen-slice multi-detector computed tomography (MDCT) permits reliable noninvasive detection of significant coronary stenosis based on qualitative visual assessment. The purpose of this study was to determine the accuracy of MDCT to quantify the degree of coronary stenosis as compared to quantitative coronary angiography (QCA) using two different reconstruction methods. Methods: We studied 69 coronary artery lesions from 38 consecutive patients that underwent 16-slice MDCT as a part of research study, which enrolled consecutive subjects scheduled for clinically indicated invasive coronary angiography. Nine coronary artery lesions with motion artifacts, heavily calcified plaques or stents were excluded from the analysis. The degree of stenosis was calculated by two independent readers non-blinded to the location of the stenosis, but blinded to the results of the QCA. MDCT luminal diameters were measured in cross-sectional multi-planar reformatted (CS-MPR) images created perpendicular to the centerline of the vessel and in 5 mm thin-slab maximum intensity projections (MIP) parallel to the long axis of the vessel. Both MDCT methods were compared against QCA. Results: The mean degree of stenosis as measured by MDCT was closely correlated to QCA for both methods (CS-MPR versus QCA: 61 {+-} 23% versus 64 {+-} 29%; r {sup 2} = 0.83, p < 0.001 and MIP versus QCA: 64 {+-} 22% versus 64 {+-} 29%; r {sup 2} = 0.84, p < 0.001 for MIP. Bland-Altman analysis demonstrated a negative bias of the degree of stenosis of -2.8 {+-} 12% using CS-MPR and a minimally positive bias of 0.6 {+-} 12% for MIP. In stratified analysis for lesion severity (mild, 0-40%; moderate, 41-70% or severe, >70%) the agreement between both CS-MPR and MIP was high when compared to QCA ({kappa} = 0.74 and 0.71, respectively). Conclusion: Multi-detector spiral CT permits accurate quantitative assessment of the degree of coronary stenosis in selected data sets of sufficient quality using both

  9. Correlations of CT and EEG findings in brain affections

    International Nuclear Information System (INIS)

    Roth, B.; Nevsimalova, S.; Kvicala, V.

    1984-01-01

    The results were compared of electroencephalography (EEG) and computerized tomography (CT) examinations of 250 patients with different brain affections. In intracranial expansive processes the pre-operative CT findings were positive in 100% cases, the EEG findings in 89.7% of cases. In severe traumatic affections the EEG and CT findings were positive in all cases, in mild injuries and post-traumatic conditions the EEG findings were more frequently positive than the CT. In focal and diffuse vascular affections the EEG and CT findings were consistent, in transitory ischemic conditions the EEG findings were more frequently positive. In inflammatory cerebral affections and in paroxymal diseases the EEG findings were positive more frequently than the CT. The same applies for demyelinating and degenerative affections. Findings of other authors were confirmed to the effect that CT very reliably reveals morphological changes in cerebral tissue while EEG records the functional state of the central nervous system and its changes. The two methods are complementary. (author)

  10. CT findings of pulmonary aspergillosis

    International Nuclear Information System (INIS)

    Cheon, Jung Eun; Im, Jung Gi; Goo, Jin Mo; Kim, Hong Dae; Han, Man Chung

    1995-01-01

    The fungus aspergillus can cause a variety of pulmonary disorders. Aspergilloma is a noninvasive aspergillus colonization of virtually any type of preexisting pulmonary cavity or cystic space. Invasive pulmonary aspergillosis is serious, usually fatal infection in patients being treated with immunosuppressants or who have chronic debilitating disease. Allergic bronchopulmonary aspergillosis is characterized clinically by asthma, blood and sputum eosinophilia and positive immunologic reaction to aspergillus antigen. Awareness of the radiographic and CT findings of pulmonary aspergillosis is important in making the diagnosis of aspergillus-caused pulmonary disorders. In this pictorial essay, we illustrated various radiological findings of pulmonary aspergillosis focused on CT findings correlated with gross pathologic specimens

  11. Postoperative CT findings of aortic aneurysm and dissection

    International Nuclear Information System (INIS)

    Seong, Su Ok; Lee, Ghi Jai; Kim, Mi Young; Moon, Hi Eun; Shim, Jae Chan; Lee, Hong Sup; Kim, Ho Kyun; Han, Chang Yul

    1995-01-01

    To assess the postoperative CT findings of aortic aneurysms or dissections treared by resection-and graft replacement or continuous-suture graft-inclusion technique. We reviewed postoperative follow-up CT findings of 14 patients, 19 cases. There were 8 patients (10 cases) of aortic aneurysm and 6 patients (9 cases) of aortic dissection which involved the thoracic aorta in 9 patients (13 cases) and abdominal aorta in 5 patients (6 cases). The interval of follow-up after operation was from 9 days to 2 year 9 months. On CT scans, we analyzed the appearance of graft materials, differences of CT findings between two surgical techniques, and normal or abnormal postoperative CT findings. Most of grafts appeared as hyperdense ring on precontrast scan, and all of them were not separated from aortic lumen on postcontrast scan. On CT findings of patients who were operated by continuous-suture graft-inclusion technique, perigraft thrombus was concentrically located with sharp demarcation by native aortic wall and its density was homogeneous, but in cases of those operated by resection-and graft replacement, perigraft hematoma was eccentrically located with indistinct margin and its density was heterogeneous and native aortic wall could not be delineated. In patients without complication, perigraft thrombus or hematoma (15 cases), perigraft calcification (11 cases), residual intimal flap (6 cases), graft deformity (4 cases), perigraft air (2 cases) and reconstructed vessels (1 cases) were noted. And in one patient with complication, perigraft flow was noted with more increased perigraft hematoma. Precise knowledge of the differences of CT findings between two surgical techniques and normal postoperative CT findings is crucial to evaluated the postoperative CT findings in aortic aneurysm and dissection

  12. Comparison of quantitatively analyzed dynamic area-detector CT using various mathematic methods with FDG PET/CT in management of solitary pulmonary nodules.

    Science.gov (United States)

    Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Fujisawa, Yasuko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

    2013-06-01

    The objective of our study was to prospectively compare the capability of dynamic area-detector CT analyzed with different mathematic methods and PET/CT in the management of pulmonary nodules. Fifty-two consecutive patients with 96 pulmonary nodules underwent dynamic area-detector CT, PET/CT, and microbacterial or pathologic examinations. All nodules were classified into the following groups: malignant nodules (n = 57), benign nodules with low biologic activity (n = 15), and benign nodules with high biologic activity (n = 24). On dynamic area-detector CT, the total, pulmonary arterial, and systemic arterial perfusions were calculated using the dual-input maximum slope method; perfusion was calculated using the single-input maximum slope method; and extraction fraction and blood volume (BV) were calculated using the Patlak plot method. All indexes were statistically compared among the three nodule groups. Then, receiver operating characteristic analyses were used to compare the diagnostic capabilities of the maximum standardized uptake value (SUVmax) and each perfusion parameter having a significant difference between malignant and benign nodules. Finally, the diagnostic performances of the indexes were compared by means of the McNemar test. No adverse effects were observed in this study. All indexes except extraction fraction and BV, both of which were calculated using the Patlak plot method, showed significant differences among the three groups (p method, pulmonary arterial perfusion calculated using the dual-input method, and perfusion calculated using the single-input method were significantly larger than that of SUVmax (p method (69.8%, p method has better potential for the diagnosis of pulmonary nodules than dynamic area-detector CT analyzed using other methods and than PET/CT.

  13. Pulmonary CT findings in acute mercury vapour exposure

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Manabu; Sato, Kimihiko; Heianna, Jyouiti; Hirano, Yoshinori; Omachi, Kohiti; Izumi, Jyunichi; Watarai, Jiro

    2001-01-01

    AIM: We describe the pulmonary computed tomography (CT) findings in acute mercury poisoning. MATERIALS AND METHODS: Initial (n= 8) and follow-up (n= 6) chest CT examinations in eight patients exposed to mercury vapour while cutting pipes in a sulphuric acid plant were reviewed. Of the eight patients, two were asymptomatic and had normal CT results, two were asymptomatic but had abnormalities on CT, and four had both acute symptoms and positive CT results. The patients were all men whose ages ranged from 37 to 54 years (mean, 49 years). RESULTS: Poorly defined nodules were present in five of six patients with positive CT findings, present alone in two patients or as part of a mixed pattern in three. They were random in distribution. Alveolar consolidation (n= 3) and areas of ground-glass opacity (n= 4) were observed and were more prominent in the most severely affected patients with the highest blood and urine level of mercury, predominantly in the upper and/or middle zone. These abnormal findings on CT resolved with (n= 1) or without (n= 5) steroid therapy. Pathological findings (n= 1) demonstrated acute interstitial changes predominantly with oedema. CONCLUSION: We report CT findings in eight patients acutely exposed to mercury vapour. The pulmonary injury was reversible on CT in these cases. Hashimoto, M. (2001)

  14. PET/CT alignment calibration with a non-radioactive phantom and the intrinsic 176Lu radiation of PET detector

    International Nuclear Information System (INIS)

    Wei, Qingyang; Ma, Tianyu; Wang, Shi; Liu, Yaqiang; Gu, Yu; Dai, Tiantian

    2016-01-01

    Positron emission tomography/computed tomography (PET/CT) is an important tool for clinical studies and pre-clinical researches which provides both functional and anatomical images. To achieve high quality co-registered PET/CT images, alignment calibration of PET and CT scanner is a critical procedure. The existing methods reported use positron source phantoms imaged both by PET and CT scanner and then derive the transformation matrix from the reconstructed images of the two modalities. In this paper, a novel PET/CT alignment calibration method with a non-radioactive phantom and the intrinsic 176 Lu radiation of the PET detector was developed. Firstly, a multi-tungsten-alloy-sphere phantom without positron source was designed and imaged by CT and the PET scanner using intrinsic 176 Lu radiation included in LYSO. Secondly, the centroids of the spheres were derived and matched by an automatic program. Lastly, the rotation matrix and the translation vector were calculated by least-square fitting of the centroid data. The proposed method was employed in an animal PET/CT system (InliView-3000) developed in our lab. Experimental results showed that the proposed method achieves high accuracy and is feasible to replace the conventional positron source based methods.

  15. PET/CT alignment calibration with a non-radioactive phantom and the intrinsic 176Lu radiation of PET detector

    Science.gov (United States)

    Wei, Qingyang; Ma, Tianyu; Wang, Shi; Liu, Yaqiang; Gu, Yu; Dai, Tiantian

    2016-11-01

    Positron emission tomography/computed tomography (PET/CT) is an important tool for clinical studies and pre-clinical researches which provides both functional and anatomical images. To achieve high quality co-registered PET/CT images, alignment calibration of PET and CT scanner is a critical procedure. The existing methods reported use positron source phantoms imaged both by PET and CT scanner and then derive the transformation matrix from the reconstructed images of the two modalities. In this paper, a novel PET/CT alignment calibration method with a non-radioactive phantom and the intrinsic 176Lu radiation of the PET detector was developed. Firstly, a multi-tungsten-alloy-sphere phantom without positron source was designed and imaged by CT and the PET scanner using intrinsic 176Lu radiation included in LYSO. Secondly, the centroids of the spheres were derived and matched by an automatic program. Lastly, the rotation matrix and the translation vector were calculated by least-square fitting of the centroid data. The proposed method was employed in an animal PET/CT system (InliView-3000) developed in our lab. Experimental results showed that the proposed method achieves high accuracy and is feasible to replace the conventional positron source based methods.

  16. Multi-detector CT features of acute intestinal ischemia and their prognostic correlations.

    Science.gov (United States)

    Moschetta, Marco; Telegrafo, Michele; Rella, Leonarda; Stabile Ianora, Amato Antonio; Angelelli, Giuseppe

    2014-05-28

    Acute intestinal ischemia is an abdominal emergency occurring in nearly 1% of patients presenting with acute abdomen. The causes can be occlusive or non occlusive. Early diagnosis is important to improve survival rates. In most cases of late or missed diagnosis, the mortality rate from intestinal infarction is very high, with a reported value ranging from 60% to 90%. Multi-detector computed tomography (MDCT) is a fundamental imaging technique that must be promptly performed in all patients with suspected bowel ischemia. Thanks to the new dedicated reconstruction program, its diagnostic potential is much improved compared to the past and currently it is superior to that of any other noninvasive technique. The increased spatial and temporal resolution, high-quality multi-planar reconstructions, maximum intensity projections, vessel probe, surface-shaded volume rending and tissue transition projections make MDCT the gold standard for the diagnosis of intestinal ischemia, with reported sensitivity, specificity, positive and negative predictive values of 64%-93%, 92%-100%, 90%-100% and 94%-98%, respectively. MDCT contributes to appropriate treatment planning and provides important prognostic information thanks to its ability to define the nature and extent of the disease. The purpose of this review is to examine the diagnostic and prognostic role of MDCT in bowel ischemia with special regard to the state of art new reconstruction software.

  17. CT findings of subdural hematomas: as a special references of atypical CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Whi Yul; Chung, Tae Sub; Suh, Jung Ho; Kim, Dong Ik; Kim, Ki Whang; Park, Chang Yun [College of Medicine, Yonsei University, Seoul (Korea, Republic of)

    1987-10-15

    Subdural hematomas (SDH) are relatively common and the typical CT findings according to the age of them are well established. The CT findings of 82 patients with SDHs were reviewed and compared with the operative findings. The results were as follow: 1. The most common cause of SDHs was the direct trauma which was noted in 60 cases (73.2%). 2. The atypical CT findings of the mixed density were seen in 19 cases (23.2%), including acute SDH 7 cases (20%), subacute SDH 5 cases (41.7%), and chronic SDH 7 cases (20%). 3. The possible causes of the mixed density in acute SDH were unclotted blood in early stage of hematoma development or serum extruded during the early phase of clot retraction. But the possibility of cerebrospinal fluid within subdural space due to an arachnoid tear could not be excluded. 4. The possible causes of the mixed density in subacute and chronic SDH were serum extruded during the hematoma resolution and rebleeding. 5. Wall enhancement of hematomas was noted in 3 cases (25%) of subacute SDHs and 15 cases (42.9%) of chronic SDHs. 6. Most of SDHs was crescentic in shape, but lenticular in 4 cases (4.9%). Midline shift and compression of ventricles were proportional to the maximum thickness of SDHs. There were seen ipsilateral dilatation of ventricles in 9 cases (11.0%) and brain edema in 11 cases (13.4%)

  18. MRI and CT findings of intracranial neurosyphilis

    International Nuclear Information System (INIS)

    Suh, Hong Kil; Shim, Ya Seong; Kim, Seon Bok; Kim, Uk Jung; Lee, Shin Ho; Jung, Hae Kyuong; Lee, Eil Seong; Kang, Ik Won; Cho, Hyeun Cha

    1999-01-01

    To evaluate the CT and MRI findings of neurosyphilis. We retrospectively reviewed the CT and MR imaging findings in five patients with intracranial neurosyphilis confirmed by CSF, VDRL, TPHA, and clinical follow-up. MR imaging was performed in all five cases, and CT in two. The MRI and CT findings of intracranial neurosyphilis included infarction (n=3), focal inflammation (n=1) and encephalopathy (n=1). There was a total of ten infaretions : three of the basal ganglia, two each of the frontal lobe, watershed zone, and cerebellum, and one of the occipital lobe. Intaretion was most common in MCA territory (n=9; 50%), followed by the watershed zone (16.6%), posterior cerebral artery territory (16.6%), and posterior inferior cerebellar artery territory (11.1%). The size of the lesion varied from 1cm to larger than one lobe. One patient showed diffuse high signal intensity in the left temporal lobe, but on follow-up MRI, this had resolved. The most common finding of neurosyphilis, as seen on MRI and CT, was infarction in middle cerebral arterial territory

  19. MRI and CT findings of intracranial neurosyphilis

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Hong Kil; Shim, Ya Seong; Kim, Seon Bok; Kim, Uk Jung; Lee, Shin Ho; Jung, Hae Kyuong; Lee, Eil Seong; Kang, Ik Won [Hallym University College of Medicine, Seoul (Korea, Republic of); Cho, Hyeun Cha [Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)

    1999-02-01

    To evaluate the CT and MRI findings of neurosyphilis. We retrospectively reviewed the CT and MR imaging findings in five patients with intracranial neurosyphilis confirmed by CSF, VDRL, TPHA, and clinical follow-up. MR imaging was performed in all five cases, and CT in two. The MRI and CT findings of intracranial neurosyphilis included infarction (n=3), focal inflammation (n=1) and encephalopathy (n=1). There was a total of ten infaretions : three of the basal ganglia, two each of the frontal lobe, watershed zone, and cerebellum, and one of the occipital lobe. Intaretion was most common in MCA territory (n=9; 50%), followed by the watershed zone (16.6%), posterior cerebral artery territory (16.6%), and posterior inferior cerebellar artery territory (11.1%). The size of the lesion varied from 1cm to larger than one lobe. One patient showed diffuse high signal intensity in the left temporal lobe, but on follow-up MRI, this had resolved. The most common finding of neurosyphilis, as seen on MRI and CT, was infarction in middle cerebral arterial territory.

  20. Basics principles of flat detector computed tomography (FD-CT)

    International Nuclear Information System (INIS)

    Kyriakou, Y.; Struffert, T.; Doerfler, A.; Kalender, W.A.

    2009-01-01

    Flat detectors (FDs) have been developed for use in radiography and fluoroscopy to replace standard X-ray film, film-screen combinations and image intensifiers (II). In comparison to X-ray film and II, FD technology offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. FDCT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. Additionally, the introduction of FD technology was a milestone for soft-tissue CT imaging in the interventional suite which was not possible with II systems in the past. This review focuses on technical and performance issues of FD technology and its wide range of applications for CT imaging. FDCT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations, but it has already proven unique for a number of dedicated CT applications offering distinct practical advantages, above all the availability of immediate CT imaging during an intervention. (orig.) [de

  1. CT scan findings in cerebral paragonimiasis

    International Nuclear Information System (INIS)

    Udaka, Fukashi; Okuda, Bungo; Okada, Masako; Okae, Shunji; Kameyama, Masakuni

    1982-01-01

    Computed tomography was performed on 5 patients with chronic cerebral paragonimiasis. CT showed solitary or multiple, amorphous, round, or oval calcifications, and ventricular enlargement in all 5 cases. A large low-density area is also found in 4 of the 5 cases. These CT findings are compatible with previously reported findings of simple X-ray films of the skull, pneumoencephalography, and pathological studies. (author)

  2. CT findings of acute cholecystitis and its complications.

    Science.gov (United States)

    Shakespear, Jonathan S; Shaaban, Akram M; Rezvani, Maryam

    2010-06-01

    The purpose of this article is to describe and illustrate the CT findings of acute cholecystitis and its complications. CT findings suggesting acute cholecystitis should be interpreted with caution and should probably serve as justification for further investigation with abdominal ultrasound. CT has a relatively high negative predictive value, and acute cholecystitis is unlikely in the setting of a negative CT. Complications of acute cholecystitis have a characteristic CT appearance and include necrosis, perforation, abscess formation, intraluminal hemorrhage, and wall emphysema.

  3. CT findings of thymic tumors

    International Nuclear Information System (INIS)

    Chung, Ho Son; Lee, Sang Jin; Hwang, Mi Soo; Cho, Kil Ho; Chang, Jae Chun; Park, Bok Hwan

    1991-01-01

    A CT scan can make accurate diagnoses of most thymic masses by assessing their size, shape, and internal architecture and is especially effective in detecting pleural implants, mediastinal involvement, and pulmonary parenchymal invasion in malignant thymoma. The authors analyzed the CT findings of 10 histologically-proven thymic masses from 1983 to 1990 in Yeungnam University Hospital. There were 10 cases of thymic masses in the anterior mediastinum consisting of 6 benign, 3 invasive thymomas, and one thymolipoma, while myasthenia gravis was associated with 2 cases of benign thymomas and with one case of invasive thymomas. The CT findings of the benign thymomas (6 cases) were well-defined, bordered, round-or oval-shaped masses with a well-preserved fat plane between the thymic mass and mediastinal great vessels, with no evidence of pleural implants and lung parenchymal invasion. The CT findings of the invasive thymomas (3 cases) were irregular, marginated lobular masses with obliteration of the fat plane between the thymic mass and surrounding great vessels, with evidence of local invasion such as extension to A-P window and mass effect to bronchus. Irregular pleural thickening due to pleural metastasis, multiple metastatic lung parenchymal nodules, and multiple mediastinal lymph node enlargement were also seen in the invasive thymomas. One case of thymolipoma showed an approximately 20cm-size, well-defined fat density mass containing internal septations

  4. CT findings of thymic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Ho Son; Lee, Sang Jin; Hwang, Mi Soo; Cho, Kil Ho; Chang, Jae Chun; Park, Bok Hwan [College of Medicine, Yeungnam University, Daegu (Korea, Republic of)

    1991-05-15

    A CT scan can make accurate diagnoses of most thymic masses by assessing their size, shape, and internal architecture and is especially effective in detecting pleural implants, mediastinal involvement, and pulmonary parenchymal invasion in malignant thymoma. The authors analyzed the CT findings of 10 histologically-proven thymic masses from 1983 to 1990 in Yeungnam University Hospital. There were 10 cases of thymic masses in the anterior mediastinum consisting of 6 benign, 3 invasive thymomas, and one thymolipoma, while myasthenia gravis was associated with 2 cases of benign thymomas and with one case of invasive thymomas. The CT findings of the benign thymomas (6 cases) were well-defined, bordered, round-or oval-shaped masses with a well-preserved fat plane between the thymic mass and mediastinal great vessels, with no evidence of pleural implants and lung parenchymal invasion. The CT findings of the invasive thymomas (3 cases) were irregular, marginated lobular masses with obliteration of the fat plane between the thymic mass and surrounding great vessels, with evidence of local invasion such as extension to A-P window and mass effect to bronchus. Irregular pleural thickening due to pleural metastasis, multiple metastatic lung parenchymal nodules, and multiple mediastinal lymph node enlargement were also seen in the invasive thymomas. One case of thymolipoma showed an approximately 20cm-size, well-defined fat density mass containing internal septations.

  5. The development, validation and application of a multi-detector CT (MDCT) scanner model for assessing organ doses to the pregnant patient and the fetus using Monte Carlo simulations

    Science.gov (United States)

    Gu, J.; Bednarz, B.; Caracappa, P. F.; Xu, X. G.

    2009-05-01

    The latest multiple-detector technologies have further increased the popularity of x-ray CT as a diagnostic imaging modality. There is a continuing need to assess the potential radiation risk associated with such rapidly evolving multi-detector CT (MDCT) modalities and scanning protocols. This need can be met by the use of CT source models that are integrated with patient computational phantoms for organ dose calculations. Based on this purpose, this work developed and validated an MDCT scanner using the Monte Carlo method, and meanwhile the pregnant patient phantoms were integrated into the MDCT scanner model for assessment of the dose to the fetus as well as doses to the organs or tissues of the pregnant patient phantom. A Monte Carlo code, MCNPX, was used to simulate the x-ray source including the energy spectrum, filter and scan trajectory. Detailed CT scanner components were specified using an iterative trial-and-error procedure for a GE LightSpeed CT scanner. The scanner model was validated by comparing simulated results against measured CTDI values and dose profiles reported in the literature. The source movement along the helical trajectory was simulated using the pitch of 0.9375 and 1.375, respectively. The validated scanner model was then integrated with phantoms of a pregnant patient in three different gestational periods to calculate organ doses. It was found that the dose to the fetus of the 3 month pregnant patient phantom was 0.13 mGy/100 mAs and 0.57 mGy/100 mAs from the chest and kidney scan, respectively. For the chest scan of the 6 month patient phantom and the 9 month patient phantom, the fetal doses were 0.21 mGy/100 mAs and 0.26 mGy/100 mAs, respectively. The paper also discusses how these fetal dose values can be used to evaluate imaging procedures and to assess risk using recommendations of the report from AAPM Task Group 36. This work demonstrates the ability of modeling and validating an MDCT scanner by the Monte Carlo method, as well as

  6. The development, validation and application of a multi-detector CT (MDCT) scanner model for assessing organ doses to the pregnant patient and the fetus using Monte Carlo simulations

    International Nuclear Information System (INIS)

    Gu, J; Bednarz, B; Caracappa, P F; Xu, X G

    2009-01-01

    The latest multiple-detector technologies have further increased the popularity of x-ray CT as a diagnostic imaging modality. There is a continuing need to assess the potential radiation risk associated with such rapidly evolving multi-detector CT (MDCT) modalities and scanning protocols. This need can be met by the use of CT source models that are integrated with patient computational phantoms for organ dose calculations. Based on this purpose, this work developed and validated an MDCT scanner using the Monte Carlo method, and meanwhile the pregnant patient phantoms were integrated into the MDCT scanner model for assessment of the dose to the fetus as well as doses to the organs or tissues of the pregnant patient phantom. A Monte Carlo code, MCNPX, was used to simulate the x-ray source including the energy spectrum, filter and scan trajectory. Detailed CT scanner components were specified using an iterative trial-and-error procedure for a GE LightSpeed CT scanner. The scanner model was validated by comparing simulated results against measured CTDI values and dose profiles reported in the literature. The source movement along the helical trajectory was simulated using the pitch of 0.9375 and 1.375, respectively. The validated scanner model was then integrated with phantoms of a pregnant patient in three different gestational periods to calculate organ doses. It was found that the dose to the fetus of the 3 month pregnant patient phantom was 0.13 mGy/100 mAs and 0.57 mGy/100 mAs from the chest and kidney scan, respectively. For the chest scan of the 6 month patient phantom and the 9 month patient phantom, the fetal doses were 0.21 mGy/100 mAs and 0.26 mGy/100 mAs, respectively. The paper also discusses how these fetal dose values can be used to evaluate imaging procedures and to assess risk using recommendations of the report from AAPM Task Group 36. This work demonstrates the ability of modeling and validating an MDCT scanner by the Monte Carlo method, as well as

  7. Multi-channel data acquisition system for CT

    International Nuclear Information System (INIS)

    Cao Fuqiang; He Bin; Liu Guohua; Xu Minjian

    2009-01-01

    The architecture design and realization of a data acquisition system for multi-channel CT is described. The article introduces the conversion of analog signal to digital signal, the data cache and transmission. This data acquisition system can be widely used in the system which requires the multi-channel, weak current signal detection. (authors)

  8. CT and MR imaging findings of xanthogranulomatous cholecystitis: correlation with pathologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Shuto, R.; Kiyosue, H.; Komatsu, E.; Matsumoto, S.; Mori, H. [Oita Medical Univ. (Japan). Dept. of Radiology; Kawano, K. [Oita Medical Univ. (Japan). Dept. of First Surgery; Kondo, Y.; Yokoyama, S. [Oita Medical Univ. (Japan). Dept. of First Pathology

    2004-03-01

    The aim of this study was to evaluate CT and MRI findings in xanthogranulomatous cholecystitis (XGC) and to correlate the imaging findings with various pathologic parameters. The study included 13 patients with histopathologically confirmed XGC. The CT (n=13) and MRI (n=5) obtained in these patients were evaluated retrospectively. On CT, low-attenuation areas in the wall of XGC correlated with foam and inflammatory cells or necrosis and/or abscess in XGC. Areas of iso- to slightly high signal intensity on T2-weighted images, showing slight enhancement at early phase and strong enhancement at last phase on dynamic study, corresponded with areas of abundant xanthogranulomas. Areas with very high signal intensity on T2-weighted images without enhancement corresponded with necrosis and/or abscesses. Luminal surface enhancement (LSE) of gallbladder wall represented preservation of the epithelial layer. The early-enhanced areas of the liver bed on dynamic CT and MR images corresponded with accumulation of inflammatory cells and abundant fibrosis. Our results indicate that CT and MRI findings correlate well with the histopathologic findings of XGC.

  9. Mesenteric vascular occlusion: Comparison of ancillary CT findings between arterial and venous occlusions and independent CT findings suggesting life-threatening events

    International Nuclear Information System (INIS)

    Wong, Yon Cheong; Wu, Cheng Hsien; Wang, Li Jen; Chen, Huan Wu; Lin, Being Chuan; Huang, Chen Chih

    2013-01-01

    To compare the ancillary CT findings between superior mesenteric artery thromboembolism (SMAT) and superior mesenteric vein thrombosis (SMVT), and to determine the independent CT findings of life-threatening mesenteric occlusion. Our study was approved by the institution review board. We included 43 patients (21 SMAT and 22 SMVT between 1999 and 2008) of their median age of 60.0 years, and retrospectively analyzed their CT scans. Medical records were reviewed for demographics, management, surgical pathology diagnosis, and outcome. We compared CT findings between SMAT and SMVT groups. Multivariate analysis was conducted to determine the independent CT findings of life-threatening mesenteric occlusion. Of 43 patients, 24 had life-threatening mesenteric occlusion. Death related to mesenteric occlusion was 32.6%. A thick bowel wall (p < 0.001), mesenteric edema (p < 0.001), and ascites (p = 0.009) were more frequently associated with SMVT, whereas diminished bowel enhancement (p = 0.003) and paralytic ileus (p = 0.039) were more frequent in SMAT. Diminished bowel enhancement (OR = 20; p = 0.007) and paralytic ileus (OR = 16; p = 0.033) were independent findings suggesting life-threatening mesenteric occlusion. The ancillary CT findings occur with different frequencies in SMAT and SMVT. However, the independent findings indicating life-threatening mesenteric occlusion are diminished bowel wall enhancement and paralytic ileus.

  10. Epstein-Barr Virus-Associated Lymphoepithelioma-Like Gastric Carcinoma Presenting as a Submucosal Mass: CT Findings with Pathologic Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Won; Shin, Hyeong Cheol; Kim, Il Young; Kim, Chang Jin; Lee, Ji Hye; Lee, Chang Kyun; Jeong, Dong Jun [Soonchunhyang University Cheonan Hospital, Cheonan(Korea, Republic of)

    2010-12-15

    A lymphoepithelioma-like carcinoma, characterized by a carcinoma with heavy lymphocyte infiltration, is one of the histological patterns observed in patients with Epstein-Barr virus (EBV)-associated gastric carcinoma. Less than half of invasive carcinomas with lymphoepithelioma-like histology can grow to make a submucosal mass. These tumors generally have a better prognosis than conventional adenocarcinomas. We report a case of an EBV-associated lymphoepitheliomalike gastric carcinoma that presented as a submucosal mass on multi-detector (MD) CT and correlate them with the pathology

  11. Epstein-Barr Virus-Associated Lymphoepithelioma-Like Gastric Carcinoma Presenting as a Submucosal Mass: CT Findings with Pathologic Correlation

    International Nuclear Information System (INIS)

    Kim, Sang Won; Shin, Hyeong Cheol; Kim, Il Young; Kim, Chang Jin; Lee, Ji Hye; Lee, Chang Kyun; Jeong, Dong Jun

    2010-01-01

    A lymphoepithelioma-like carcinoma, characterized by a carcinoma with heavy lymphocyte infiltration, is one of the histological patterns observed in patients with Epstein-Barr virus (EBV)-associated gastric carcinoma. Less than half of invasive carcinomas with lymphoepithelioma-like histology can grow to make a submucosal mass. These tumors generally have a better prognosis than conventional adenocarcinomas. We report a case of an EBV-associated lymphoepitheliomalike gastric carcinoma that presented as a submucosal mass on multi-detector (MD) CT and correlate them with the pathology

  12. Volumetric CT with sparse detector arrays (and application to Si-strip photon counters).

    Science.gov (United States)

    Sisniega, A; Zbijewski, W; Stayman, J W; Xu, J; Taguchi, K; Fredenberg, E; Lundqvist, Mats; Siewerdsen, J H

    2016-01-07

    % reduction in the dispersion of SSIM in the volume compared to the constant penalty (both penalties applied at optimal regularization strength). Images of the spherical clutter and wrist phantoms confirmed the advantages of the spatially varying penalty, showing a 25% improvement in image uniformity and 1.8  ×  higher CNR (at matched spatial resolution) compared to the constant penalty. The studies elucidate the relationship between sampling in the detector plane, acquisition orbit, sampling of the reconstructed volume, and the resulting image quality. They also demonstrate the benefit of spatially varying regularization in MBIR for scenarios with irregular sampling patterns. Such findings are important and integral to the incorporation of a sparsely sampled Si-strip PCD in CT imaging.

  13. Multi-slice spiral CT diagnosis of carotid body tumor

    International Nuclear Information System (INIS)

    Li Peiling; Leng Renli; Li Shu; Xie Xiuli; Xu Ke

    2006-01-01

    Objective: to explore the Multi-slice spiral CT (MSCT) findings of carotid body tumor (CBT). Methods: Twelve cases of CBT proved by surgery were collected in this study and all patients accepted contrast-enhanced MSCT examination. Two-dimensional and three-dimensional post-processing were performed at diagnostic workstation using Aquilion 1.42. The CT features of CBT were analyzed. Results Each of 12 patients had one lesion. All lesions demonstrated well-marginated masses of homogeneous soft- tissue density with CT value within 29-48 HU on pre-enhanced images. All lesions were markedly enhanced with CT value over 200 HU on arterial-phase images, and the density of lesions decreased rapidly on delay- phase images. Twelve lesions were all located at the level of carotid artery bifurcation, 3 of them enveloping common carotid artery and internal/external carotid artery, and other 9 of them riding right on the carotid bifurcation. Internal carotid artery usually were shifted toward posterior-lateral, and external carotid artery toward anterior or anterior-medial. Conclusion: Contrast-enhanced MSCT examination not only can make a qualitative diagnosis of CBT, but determine its accurate location. It plays an importantly instructional role in clinical diagnosis and treatment. (authors)

  14. Can 16-detector multislice CT exclude skeletal lesions during tumour staging? Implications for the cancer patient

    International Nuclear Information System (INIS)

    Groves, Ashley M.; Beadsmoore, Clare J.; Courtney, Helen M.; Harish, Srinivasan; Bearcroft, Philip W.P.; Dixon, Adrian K.; Cheow, Heok K.; Balan, Kottekkattu K.; Kaptoge, Stephen; Win, Thida

    2006-01-01

    Current imaging guidelines recommend that many cancer patients undergo soft-tissue staging by computed tomography (CT) whilst the bones are imaged by skeletal scintigraphy (bone scan). New CT technology has now made it feasible, for the first time, to perform a detailed whole-body skeletal CT. This advancement could save patients from having to undergo duplicate investigations. Forty-three patients with known malignancy were investigated for bone metastasis using skeletal scintigraphy and 16-detector multislice CT. Both studies were performed within six weeks of each other. Whole-body images were taken 4 h after injection of 500 Mbq 99m Tc-MDP using a gamma camera. CT was performed on a 16-detector multislice CT machine from the vertex to the knee. The examinations were reported independently and discordant results were compared at follow-up. Statistical equivalence between the two techniques was tested using the Newcombe-Wilson method within the pre-specified equivalence limits of ±20%. Scintigraphy detected bone metastases in 14/43 and CT in 13/43 patients. There were seven discordances; four cases were positive on scintigraphy, but negative on CT; three cases were positive on CT and negative on scintigraphy. There was equivalence between scintigraphy and CT in detecting bone metastases within ±19% equivalence limits. Patients who have undergone full whole-body staging on 16-detector CT may not need additional skeletal scintigraphy. This should shorten the cancer patient's diagnostic pathway. (orig.)

  15. PET/CT alignment calibration with a non-radioactive phantom and the intrinsic {sup 176}Lu radiation of PET detector

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Qingyang [School of Automation and Electrical Engineering, University of Science & Technology Beijing, Beijing 100083 (China); Ma, Tianyu; Wang, Shi; Liu, Yaqiang [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Gu, Yu, E-mail: guyu@ustb.edu.cn [School of Automation and Electrical Engineering, University of Science & Technology Beijing, Beijing 100083 (China); Dai, Tiantian, E-mail: maxinedtt@163.com [Department of Radiation Oncology, China-Japan Friendship Hospital, Beijing 100029 (China)

    2016-11-01

    Positron emission tomography/computed tomography (PET/CT) is an important tool for clinical studies and pre-clinical researches which provides both functional and anatomical images. To achieve high quality co-registered PET/CT images, alignment calibration of PET and CT scanner is a critical procedure. The existing methods reported use positron source phantoms imaged both by PET and CT scanner and then derive the transformation matrix from the reconstructed images of the two modalities. In this paper, a novel PET/CT alignment calibration method with a non-radioactive phantom and the intrinsic {sup 176}Lu radiation of the PET detector was developed. Firstly, a multi-tungsten-alloy-sphere phantom without positron source was designed and imaged by CT and the PET scanner using intrinsic {sup 176}Lu radiation included in LYSO. Secondly, the centroids of the spheres were derived and matched by an automatic program. Lastly, the rotation matrix and the translation vector were calculated by least-square fitting of the centroid data. The proposed method was employed in an animal PET/CT system (InliView-3000) developed in our lab. Experimental results showed that the proposed method achieves high accuracy and is feasible to replace the conventional positron source based methods.

  16. Triple rule-out CT in the emergency department: protocols and spectrum of imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Frauenfelder, Thomas; Appenzeller, Philippe; Karlo, Christoph; Scheffel, Hans; Desbiolles, Lotus; Stolzmann, Paul; Marincek, Borut; Alkadhi, Hatem; Schertler, Thomas [University Hospital Zurich, Department of Medical Radiology, Institute of Diagnostic Radiology, Zurich (Switzerland)

    2009-04-15

    Triage decisions in patients suffering from acute chest pain remain a challenge. The patient's history, initial cardiac enzyme levels, or initial electrocardiograms (ECG) often do not allow selecting the patients in whom further tests are needed. Numerous vascular and non-vascular chest problems, such as pulmonary embolism (PE), aortic dissection, or acute coronary syndrome, as well as pulmonary, pleural, or osseous lesions, must be taken into account. Nowadays, contrast-enhanced multi-detector-row computed tomography (CT) has replaced previous invasive diagnostic procedures and currently represents the imaging modality of choice when the clinical suspicion of PE or acute aortic syndrome is raised. At the same time, CT is capable of detecting a multitude of non-vascular causes of acute chest pain, such as pneumonia, pericarditis, or fractures. Recent technical advances in CT technology have also shown great advantages for non-invasive imaging of the coronary arteries. In patients with acute chest pain, the optimization of triage decisions and cost-effectiveness using cardiac CT in the emergency department have been repetitively demonstrated. Triple rule-out CT denominates an ECG-gated protocol that allows for the depiction of the pulmonary arteries, thoracic aorta, and coronary arteries within a single examination. This can be accomplished through the use of a dedicated contrast media administration regimen resulting in a simultaneous attenuation of the three vessel territories. This review is intended to demonstrate CT parameters and contrast media administration protocols for performing a triple rule-out CT and discusses radiation dose issues pertinent to the protocol. Typical life-threatening and non-life-threatening diseases causing acute chest pain are illustrated. (orig.)

  17. Evidence-based recommendations for musculoskeletal kinematic 4D-CT studies using wide area-detector scanners: a phantom study with cadaveric correlation

    Energy Technology Data Exchange (ETDEWEB)

    Gondim Teixeira, Pedro Augusto; Formery, Anne-Sophie; Blum, Alain [CHRU-Nancy Hopital Central, Service d' Imagerie Guilloz, Nancy (France); Hossu, Gabriela [Universite de Lorraine, IADI U947, Nancy (France); INSERM, CIC-IT 1433, Nancy (France); Winninger, Daniel [IDCmem, Nancy (France); Batch, Toufik [Hopital de Mercy, Service de Radiologie, Metz (France); Gervaise, Alban [Legouest Military Instruction Hospital, Medical Imaging Department, Metz (France)

    2017-02-15

    To establish evidence-based recommendations for musculoskeletal kinematic 4D-CT on wide area-detector CT. In order to assess factors influencing image quality in kinematic CT studies, a phantom consisting of a polymethylmethacrylate rotating disk with round wells of different sizes was imaged with various acquisition protocols. Cadaveric acquisitions were performed on the ankle joint during motion in two different axes and at different speeds to allow validation of phantom data. Images were acquired with a 320 detector-row CT scanner and were evaluated by two readers. Motion artefacts were significantly correlated with various parameters (movement axis, distance to centre, rotation speed and volume acquisition speed) (p < 0.0001). The relation between motion artefacts and distance to motion fulcrum was exponential (R{sup 2} 0.99). Half reconstruction led to a 23 % increase in image noise and a 40 % decrease in motion artefacts. Cadaveric acquisitions confirmed phantom data. Based on these findings, high tube rotation speed and half reconstruction are recommended for kinematic CT. The axis of motion significantly influences image artefacts and should be considered in patient training and evaluation of acquisition protocol suitability. This study provides evidence-based recommendations for musculoskeletal kinematic 4D-CT. (orig.)

  18. CT findings in isolated ischemic proctosigmoiditis

    International Nuclear Information System (INIS)

    Wiesner, Walter; Mortele, Koenraad J.; Ji, Hoon; Khurana, Bharti; Ros, Pablo R.; Glickman, Jonathan N.

    2002-01-01

    The purpose of our study was to describe the CT features of ischemic proctosigmoiditis in correlation with clinical, laboratory, endoscopic, and histopathologic findings. Our study included seven patients with isolated ischemic proctosigmoiditis. Patients were identified by a retrospective review of all histopathologic records of colonoscopic biopsies performed during a time period of 4 years. All patients presented with left lower abdominal quadrant pain, bloody stools, and leukocytosis, and four patients had fever at the time of presentation. Four of seven patients suffered from diarrhea, one of seven was constipated and two of seven had normal stool consistency. The CT examinations were reviewed by two authors by consensus and compared with clinical and histopathologic results as well as with the initial CT diagnosis. The CT showed a wall thickening confined to the rectum and sigmoid colon in seven of seven patients, stranding of the pararectal fat in four of seven, and stranding of the perisigmoidal fat in one of seven patients. There were no enlarged lymph nodes, but five of seven patients showed coexistent diverticulosis and in three of these patients CT findings were initially misinterpreted as sigmoid diverticulitis. Endoscopies and histopathologic analyses of endoscopic biopsies confirmed non-transmural ischemic proctosigmoiditis in all patients. Isolated ischemic proctosigmoiditis often presents with unspecific CT features and potentially misleading clinical and laboratory findings. In an elderly patient or a patient with known cardiovascular risk factors the diagnosis of ischemic proctosigmoiditis should be considered when wall thickening confined to the rectum and sigmoid colon is seen that is associated with perirectal fat stranding. (orig.)

  19. CT and MRI findings in cerebral hydatid disease

    International Nuclear Information System (INIS)

    Topal, U.; Parlak, M.; Kilic, E.; Sivri, Z.; Sadikoglu, M.Y.; Tuncel, E.

    1995-01-01

    CT is the primary modality for the diagnosis. Two forms of cerebral hydatid cysts have been reported on the basis of CT appearances: unilocular and multilocular. Demonstration of the cyst wall is important for the diagnosis. MRI is superior to CT for demonstrating the cyst capsule and perifocal oedema. We retrospectively reveiwed the CT and MRI findings of 6 surgically proven cases of cerebral hydatid cyst and compared the two modalities on the basis of their demonstration of findings helpful in the diagnosis, such as the capsule and perifocal oedema. In 1 case CT showed the capsule. In 2 cases MRI showed a hypointense capsule around the cyst on T2-weighted images. While CT is the modality of choice, in clinical practice MRI is superior for demonstrating the cyst capsule, which is a helpful finding in the diagnosis and can be used in inconclusive cases. (orig.)

  20. CT findings of orbital langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Yi, Gina; Yoon, Hye Kyung; Han, Bokyung Kim; Kim, Kyeong Ah; Choo, In Wook

    2000-01-01

    To evaluate the CT findings in patients with Langerhans cell histiocytosis (LCH) involving the orbit. Orbital CT scans of six children with pathologically proven LCH were retrospectively analyzed. Follow-up CT (n=3D5) and MR (n=3D1) imaging findings were also reviewed. Initial CT scans revealed varying degree of bone destruction with soft-tissue masses, and on nonenhanced images the mean attenuation value was 44 Hounsfield units (HU). All masses showed mild to moderate enhancement with a mean attenuation value of 74 HU. The bony margins abutting onto soft tissue masses were irregular but clearly demarcated. No evidence of calcification or periosteal reaction was noted. Suprasellar mass and rib involvement was noted in one patient and hepatosplenomegaly in two. Follow-up CT and MR images showed that the soft tissue masses were almost completely resolved, with bone remodeling and reossification. A soft tissue mass with irregular but clearly demarcated bone destruction is thought to be a characteristic finding of LCH involving the orbit. Follow-up images after treatment showed bone remodeling and reossification. (author)

  1. Evaluation of CT findings for diagnosis of pleural effusions

    International Nuclear Information System (INIS)

    Arenas-Jimenez, J.; Alonso-Charterina, S.; Fernandez-Latorre, F.; Gil-Sanchez, S.; Sanchez-Paya, J.; Lloret-Llorens, M.

    2000-01-01

    Computed tomography studies are usually used to assess patients with pleural effusions, and radiologists should be aware of the significance of different CT findings for the diagnosis of the effusion. The purpose of this study was to evaluate CT findings for etiological diagnosis of pleural effusions. Contrast-enhanced CT of the chest of 211 patients with pleural effusion of definite diagnosis were evaluated. The CT images were evaluated for the presence and extent of pleural effusion, thickening or nodules, extrapleural fat and other changes in the mediastinum or lung. The CT scans were read by two independent observers and correlation between them was evaluated. Comparison of CT findings between benign and malignant effusions, between exudates and transudates, and between empyemas and the other parapneumonic effusions were carried out. Kappa values for most CT findings were >0.85. Loculation, pleural thickening, pleural nodules, and extrapleural fat of increased density were only present in exudative effusions. Multiple pleural nodules and nodular pleural thickening were the only pleural findings limited to malignant pleural effusions. The signs were also more frequently seen in empyemas than in other parapneumonic effusions. Computed tomography findings can help to distinguish between transudates and exudates. Although there is some overlap between benign and malignant pleural effusions, pleural nodules and nodular pleural thickening were present almost exclusively in the latter. Although differences between CT findings of empyemas and the other parapneumonic effusions exist, there is no finding which can definitely differentiate between them. (orig.)

  2. Development and performance evaluation of an experimental fine pitch detector multislice CT scanner.

    Science.gov (United States)

    Imai, Yasuhiro; Nukui, Masatake; Ishihara, Yotaro; Fujishige, Takashi; Ogata, Kentaro; Moritake, Masahiro; Kurochi, Haruo; Ogata, Tsuyoshi; Yahata, Mitsuru; Tang, Xiangyang

    2009-04-01

    The authors have developed an experimental fine pitch detector multislice CT scanner with an ultrasmall focal spot x-ray tube and a high-density matrix detector through current CT technology. The latitudinal size of the x-ray tube focal spot was 0.4 mm. The detector dimension was 1824 channels (azimuthal direction) x 32 rows (longitudinal direction) at row width of 0.3125 mm, in which a thinner reflected separator surrounds each detector cell coupled with a large active area photodiode. They were mounted on a commercial 64-slice CT scanner gantry while the scan field of view (50 cm) and gantry rotation speed (0.35 s) can be maintained. The experimental CT scanner demonstrated the spatial resolution of 0.21-0.22 mm (23.8-22.7 lp/cm) with the acrylic slit phantom and in-plane 50%-MTF 9.0 lp/cm and 10%-MTF 22.0 lp/cm. In the longitudinal direction, it demonstrated the spatial resolution of 0.24 mm with the high-resolution insert of the CATPHAN phantom and 0.34 mm as the full width at half maximum of the slice sensitivity profile. In low-contrast detectability, 3 mm at 0.3% was visualized at the CTDI(vol) of 47.2 mGy. Two types of 2.75 mm diameter vessel phantoms with in-stent stenosis at 25%, 50%, and 75% stair steps were scanned, and the reconstructed images can clearly resolve the stenosis at each case. The experimental CT scanner provides high-resolution imaging while maintaining low-contrast detectability, demonstrating the potentiality for clinical applications demanding high spatial resolution, such as imaging of inner ear, lung, and bone, or low-contrast detectability, such as imaging of coronary artery.

  3. Comparison of CT findings with upper GI series and surgical findings

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jin Kyo; Suh, Soo Jhi; Kim, Soon Yong [School of Medicine, Kyung Hee University, Seoul (Korea, Republic of)

    1981-09-15

    The authors made comparative studies of CT findings with upper GI series and surgical findings in 20 cases of histologically proven gastric cancers. The identification of chickening of gastric wall and local and remote metastasis by CT was thought to be great value in treatment planning and prediction of prognosis of the patients. The results were as follows: 1. Of 20 cases, 19 cases demonstrated thickening of gastric wall. Among 3 cases suggested as early cancer on upper GI series, 2 cases demonstrated thickened gastric wall on CT and it was proved to be advanced cancer at surgery. 2. Out of 8 cases showed no definite metastasis on CT, 4 cases had malignant infiltration histologically in the regional lymph nodes. But they were less than 1.5 cm in diameter. 3. The frequency order of remote metastasis found by CT was pancreas, liver, left adrenal gland and lung in organs and retroperitoneal, retrocrural and regional nodes in lymph nodes.

  4. Prevalence of ligamentum arteriosum calcification on multi-section spiral CT and digital radiography.

    Science.gov (United States)

    Hong, Gil-Sun; Goo, Hyun Woo; Song, Jae-Woo

    2012-06-01

    To investigate the prevalence of ligamentum arteriosum calcification (LAC) on multi-section spiral CT and digital radiography. Five hundred and eight children and 232 adults who performed multi-section chest CT were included in this study and were divided into nine age groups: A (0-5 years), B (6-10 years), C (11-15 years), D (16-20 years), E (21-30 years), F (31-40 years), G (41-50 years), H (51-60 years), and I (61-70 years). Two radiologists assessed the presence of LAC on axial and coronal CT images, defined as focal calcific density on both or on one plane with attenuation >100 Hounsfield unit. The prevalence of LAC on CT was compared between children and adults, and between unenhanced and enhanced CT in children. The prevalence of LAC on digital radiography was evaluated in 476 children. The prevalence of definite LAC on unenhanced multi-section CT was significantly higher in children (37.8 %) than in adults (11.2 %) (P CT were 4.5, 12.8, 8.1, 19.0, 0.0, 0.0, 0.0, 2.0, and 1.9 %. In children, the prevalence of LAC was significantly higher on unenhanced than on enhanced CT (37.8 vs. 16.4 %, P children. LAC is frequently observed in children and adults on multi-section spiral CT, more frequently than previously reported. Compared with that on multi-section spiral CT, the prevalence of LAC on digital radiography is substantially low.

  5. Development of planar CT system for multi-layer PCB inspection

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Ho; Youn, Hanbean; Kam, Soohwa; Park, Eunpyeong; Kim, Ho Kyung [Pusan National University, Busan (Korea, Republic of)

    2015-05-15

    X-ray defect inspection apparatus can be used in the production line to inspect the PCB. However, a simple X-ray radiography cannot discriminate defects from the multi-layer PCBs because the layers of them overlays the defects. To complement this issue, computed tomography (CT) technology is applied to the NDT system which can offer 3-dimensional information of object. However, CT requires hundreds of projection images to examine a single PCB, hence real-time inspection is nearly impossible. In this study, we develop a planar computed tomography (pCT) system appropriate for the multi-layer PCB inspection. For the image reconstruction of planar cross-section images, we use the digital tomosynthesis (DTS) concept in association with the limited angle scanning. and performance characterization of the pCT system for the PCB inspection. The 3-d Fourier characteristics and more quantitative performance, such as contrast, uniformity, depth resolution will be presented. The cross-sectional images of multi-layer PCBs will also be demonstrated.

  6. Finite detector based projection model for super resolution CT

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hengyong; Wang, Ge [Wake Forest Univ. Health Sciences, Winston-Salem, NC (United States). Dept. of Radiology; Virgina Tech, Blacksburg, VA (United States). Biomedical Imaging Div.

    2011-07-01

    For finite detector and focal spot sizes, here we propose a projection model for super resolution CT. First, for a given X-ray source point, a projection datum is modeled as an area integral over a narrow fan-beam connecting the detector elemental borders and the X-ray source point. Then, the final projection value is expressed as the integral obtained in the first step over the whole focal spot support. An ordered-subset simultaneous algebraic reconstruction technique (OS-SART) is developed using the proposed projection model. In the numerical simulation, our method produces super spatial resolution and suppresses high-frequency artifacts. (orig.)

  7. Pulmonary lymphangioleiomyomatosis: high-resolution CT findings

    International Nuclear Information System (INIS)

    Kirchner, J.; Stein, A.; Thalhammer, A.; Jacobi, V.

    1999-01-01

    Lymphangioleiomyomatosis (LAM) of the lung is a very rare disease. There are obvious discrepancies in the literature concerning the appearance of LAM on CT scans of the lung. This study adds the imaging findings of 11 patients and demonstrates how the imaging findings changed over time in four patients. Twenty-two CT examinations, and radiographs that had been obtained close to the CT examinations, of 11 patients with LAM confirmed by open lung biopsy were retrospectively evaluated with particular attention to the size of cystic lesions and wall thickness. Furthermore the CT scans were analysed for the type of pulmonary infiltration process and its distribution, presence or absence of pleural effusion, pneumothorax and lymph node enlargement. Clinical and CT follow-up studies were available in four patients. The CT scans revealed an increase in the interstitial pattern in all patients. Architectural distortion was seen in two patients and cystic lesions were present in all. The size of the cysts varied from small lesions to bullous emphysema. The cystic lesions revealed a wall thickness up to 2 mm but a wall was not perceptible in all. Pneumothorax was seen in only two patients; pleural effusion was seen in two patients. CT examination of patients with LAM reveals neither a uniform nor a pathognomonic appearance. In the early stages of LAM or in cases with interstitial changes the differential diagnosis of centrilobular emphysema or idiopathic pulmonary fibrosis seems to be more difficult than most authors believe. (orig.) (orig.)

  8. CT findings in silicosis due to denim sandblasting

    International Nuclear Information System (INIS)

    Alper, Fatih; Akgun, Metin; Araz, Omer; Onbas, Omer

    2008-01-01

    The purpose of this study was to describe the findings of CT performed on denim sandblasters with silicosis. Fifty consecutive male patients with silicosis were evaluated. Their clinical data and pulmonary function tests (PFT) were obtained. The CT findings were recorded and the correlations between CT nodular profusion score and the other parameters were assessed. The diagnoses of the patients were classified as accelerated silicosis (n = 43) and acute silicosis (n = 7). The most common CT finding was centrilobular nodules. Twenty-three patients had complicated silicosis based on pleural involvement and presence of progressive massive fibrosis (PMF). Lymphadenopathy (LAP) was positive in 50% of the patients, with calcification in 24%. The CT grade was highly correlated with the clinical data such as exposure duration and PFT. Our findings suggest that the clinical manifestation of silicosis in denim sandblasters is severe. Although the duration of exposure is shorter the rate of complicated silicosis patients with pleural involvement was unexpectedly higher in the cases. Because the most common radiological appearance was nodules and the CT grading of the nodules was highly correlated with the clinical data, nodule grading may be used in the management of such cases. (orig.)

  9. CT findings following diphenylhydantoin intoxication

    International Nuclear Information System (INIS)

    Baier, W.K.; Beck, U.; Hirsch, W.; Kiel Univ.

    1985-01-01

    CT findings in three female epileptic patients are presented. The patients were treated with toxic doses of the anticonvulsant diphenylhydantoin, leading to irreversible ataxia of varying severity. CT shows cerebellar atrophy, including discernible sulci, a dilated 4th ventricle, basal cisterns, and subarachnoid space. These effects of severe DPH toxicity are in the differential diagnosis from the ''idiopathic'' and other toxic and systemic atrophies, as well as from the dysontogenetic lesions of the cerebellum. (orig.)

  10. CT findings in primary pulmonary lymphomas

    International Nuclear Information System (INIS)

    Cardinale, Luciano; Allasia, Marco; Cataldi, Aldo; Ferraris, Fabrizio; Fava, Cesare; Parvis, Guido

    2005-01-01

    Purpose. To describe the CT findings of pathologically confirmed primary pulmonary lymphomas. Materials and methods. The CT examinations of 11 patients with pathologically proven primary pulmonary lymphoma (9 BALT lymphomas and 2 non-BALT lymphomas) were retrospectively reviewed by three radiologists. Evaluated findings included morphology (consolidation, mass, nodule), number and distribution of lesions. Other CT findings such as air bronchogram, lymphadenopathy atelectasis and pleural effusion were also assessed. Results. Pulmonary lesions were depicted as air-space consolidation (pneumonia-like) in 5 patients (45%), tumour-like rounded opacity in 4 (36%), and nodules in 4 (36%). Multiple and bilateral long lesions were seen in 3 patients (27%). Air bronchogram was present in 7 patients (63%), lymphadenopathy in 3 (27%), atelectasis in 4 (36%) and pleural effusion in only 1 (9%). Conclusions. Our results agree with previous studies regarding lesion patterns and their relative frequency. A smaller number of nodules and of multiple lesions were found compared with some previous studies. The most frequent pattern was airspace consolidation [it

  11. Variation in the quality of CT images of the upper abdomen when CT automatic exposure control is employed

    International Nuclear Information System (INIS)

    Aizawa, Isao; Muramatsu, Yoshihisa; Nomura, Keiichi; Shimizu, Fuminori

    2010-01-01

    The aim of this study was to analyze the reason for variation of image quality in the upper abdomen CT with the use of CT-automatic exposure control (AEC). The CT investigated was 3D modulation in the 16 multi detector row CT (MDCT) and lung cancer screening CT (LSCT) phantom was used to simulate the patient. When there was a phase difference, an image noise increase of around 15% at the maximum was accepted. It is concluded that the major reason for variation in image quality is respiratory motion and the importance of respiration control must be recognized. (author)

  12. Calibration and GEANT4 Simulations of the Phase II Proton Compute Tomography (pCT) Range Stack Detector

    Energy Technology Data Exchange (ETDEWEB)

    Uzunyan, S. A. [Northern Illinois Univ., DeKalb, IL (United States); Blazey, G. [Northern Illinois Univ., DeKalb, IL (United States); Boi, S. [Northern Illinois Univ., DeKalb, IL (United States); Coutrakon, G. [Northern Illinois Univ., DeKalb, IL (United States); Dyshkant, A. [Northern Illinois Univ., DeKalb, IL (United States); Francis, K. [Northern Illinois Univ., DeKalb, IL (United States); Hedin, D. [Northern Illinois Univ., DeKalb, IL (United States); Johnson, E. [Northern Illinois Univ., DeKalb, IL (United States); Kalnins, J. [Northern Illinois Univ., DeKalb, IL (United States); Zutshi, V. [Northern Illinois Univ., DeKalb, IL (United States); Ford, R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Rauch, J. E. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Rubinov, P. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Sellberg, G. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Wilson, P. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Naimuddin, M. [Univ. of Delhi, New Delhi (India)

    2015-12-29

    Northern Illinois University in collaboration with Fermi National Accelerator Laboratory (FNAL) and Delhi University has been designing and building a proton CT scanner for applications in proton treatment planning. The Phase II proton CT scanner consists of eight planes of tracking detectors with two X and two Y coordinate measurements both before and after the patient. In addition, a range stack detector consisting of a stack of thin scintillator tiles, arranged in twelve eight-tile frames, is used to determine the water equivalent path length (WEPL) of each track through the patient. The X-Y coordinates and WEPL are required input for image reconstruction software to find the relative (proton) stopping powers (RSP) value of each voxel in the patient and generate a corresponding 3D image. In this Note we describe tests conducted in 2015 at the proton beam at the Central DuPage Hospital in Warrenville, IL, focusing on the range stack calibration procedure and comparisons with the GEANT~4 range stack simulation.

  13. CT findings following diphenylhydantoin intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Baier, W.K.; Beck, U.; Hirsch, W.

    1985-05-01

    CT findings in three female epileptic patients are presented. The patients were treated with toxic doses of the anticonvulsant diphenylhydantoin, leading to irreversible ataxia of varying severity. CT shows cerebellar atrophy, including discernible sulci, a dilated 4th ventricle, basal cisterns, and subarachnoid space. These effects of severe DPH toxicity are in the differential diagnosis from the ''idiopathic'' and other toxic and systemic atrophies, as well as from the dysontogenetic lesions of the cerebellum.

  14. Pulmonary lymphangioleiomyomatosis: high-resolution CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Kirchner, J.; Stein, A.; Thalhammer, A.; Jacobi, V. [Mainz Univ. (Germany). Inst. fuer Allgemeine Roentgendiagnostik; Viel, K.; Dietrich, C.F. [Frankfurt Univ. (Germany). Medizinische Klinik II; Schneider, M. [Zentrum fuer Pathologie, Frankfurt Univ. (Germany)

    1999-02-01

    Lymphangioleiomyomatosis (LAM) of the lung is a very rare disease. There are obvious discrepancies in the literature concerning the appearance of LAM on CT scans of the lung. This study adds the imaging findings of 11 patients and demonstrates how the imaging findings changed over time in four patients. Twenty-two CT examinations, and radiographs that had been obtained close to the CT examinations, of 11 patients with LAM confirmed by open lung biopsy were retrospectively evaluated with particular attention to the size of cystic lesions and wall thickness. Furthermore the CT scans were analysed for the type of pulmonary infiltration process and its distribution, presence or absence of pleural effusion, pneumothorax and lymph node enlargement. Clinical and CT follow-up studies were available in four patients. The CT scans revealed an increase in the interstitial pattern in all patients. Architectural distortion was seen in two patients and cystic lesions were present in all. The size of the cysts varied from small lesions to bullous emphysema. The cystic lesions revealed a wall thickness up to 2 mm but a wall was not perceptible in all. Pneumothorax was seen in only two patients; pleural effusion was seen in two patients. CT examination of patients with LAM reveals neither a uniform nor a pathognomonic appearance. In the early stages of LAM or in cases with interstitial changes the differential diagnosis of centrilobular emphysema or idiopathic pulmonary fibrosis seems to be more difficult than most authors believe. (orig.) (orig.) With 5 figs., 2 tabs., 21 refs.

  15. [Clinical application of high-pitch excretory phase images during dual-source CT urography with stellar photon detector].

    Science.gov (United States)

    Sun, Hao; Xue, Hua-dan; Jin, Zheng-yu; Wang, Xuan; Chen, Yu; He, Yong-lan; Zhang, Da-ming; Zhu, Liang; Wang, Yun; Qi, Bing; Xu, Kai; Wang, Ming

    2014-10-01

    To retrospectively evaluate the clinical feasibility of high-pitch excretory phase images during dual-source CT urography with Stellar photon detector. Totally 100 patients received dual-source CT high-pitch urinary excretory phase scanning with Stellar photon detector [80 kV, ref.92 mAs, CARE Dose 4D and CARE kV, pitch of 3.0, filter back projection reconstruction algorithm (FBP)] (group A). Another 100 patients received dual-source CT high-pitch urinary excretory phase scanning with common detector(100 kV, ref.140 mAs, CARE Dose 4D, pitch of 3.0, FBP) (group B). Quantitative measurement of CT value of urinary segments (Hounsfield units), image noise (Hounsfield units), and effective radiation dose (millisievert) were compared using independent-samples t test between two groups. Urinary system subjective opacification scores were compared using Mann-Whitney U test between two groups. There was no significant difference in subjective opacification score of intrarenal collecting system and ureters between two groups (all P>0.05). The group A images yielded significantly higher CT values of all urinary segments (all P0.05). The effective radiation dose of group A (1.1 mSv) was significantly lower than that of group B (3.79 mSv) (Ppitch low-tube-voltage during excretory phase dual-source CT urography with Stellar photon detector is feasible, with acceptable image noise and lower radiation dose.

  16. Diagnostic performance of 320-detector CT coronary angiography in patients with atrial fibrillation: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lei; Yang, Lin; Fan, Zhanming; Yu, Wei; Lv, Biao; Zhang, Zhaoqi [Capital Medical University, Department of Radiology, Beijing Anzhen Hospital, Beijing (China)

    2011-05-15

    To evaluate the feasibility, diagnostic accuracy, and radiation dose of CT coronary angiography (CTCA) in patients with atrial fibrillation (AF) using 320-detector CT. Thirty-seven patients with persistent AF and suspected coronary artery disease (CAD) were enrolled. All patients underwent both 320-detector CTCA and conventional coronary angiography (CCA). CT image quality and the presence of significant ({>=}50%) stenosis were evaluated by two radiologists blinded to the results of CCA. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated using CCA as the reference standard. Differences in detection of coronary artery stenosis between 320-detector CTCA and CCA were evaluated with McNemar's test. Patient radiation dose was calculated by multiplying dose length product by conversion coefficient of 0.017. In total 474 evaluated coronary segments, 459 (96.8%) segments were diagnostically evaluable. On per-segment analysis, sensitivity, specificity, PPV and NPV were 90.0% (18 of 20), 99.3% (436 of 439), 85.7% (18 of 21) and 99.5% (436 of 438). No significant difference was found between 320-detector CTCA and CCA on the detection of significant stenosis (P = 1.000). Effective doses of 320-detector CTCA was 13.0 {+-} 4.7 mSv. 320-detector CTCA is feasible and accurate in excluding CAD in patients with AF. (orig.)

  17. Traumatic rupture of the diaphragm: CT findings

    International Nuclear Information System (INIS)

    Cho, Sung Tae; Kim, Sung Jin; Cha, Sang Hoon; Park, Kil Sun; Kim, Jin Hee; Yim, Se Hwan

    1995-01-01

    The aim of this study was to assess the clinical utility of the known CT signs of the traumatic rupture of the diaphragm. CT scans and chest radiographs were retrospectively reviewed in 13 patients who had diaphragmatic rupture confirmed by surgery. On chest radiographs the elevation of the diaphragm was evaluated. On CT, 1) discontinuity of the diaphragm, 2) lack of depiction of the diaphragm surrounding the herniated intraabdominal organs (absent diaphragm sign), and 3) fat seen lateral to the diaphragm (fat sign) were evaluated. Chest radiographs showed the elevation of the diaphragm in 11 patients (85%). CT scan showed absent diaphragm sign in 11 patients (85%), discontinuity of the diaphragm in 8 (62%), and fat sign in 7 (54%). All of 12 patients who had the left diaphragmatic rupture had one or more of the above findings. Discontinuity of the diaphragm, absent diaphragm sign, and fat sign may be helpful CT findings in the diagnosis of the traumatic rupture of the left diaphragm

  18. Multi-energy x-ray detectors to improve air-cargo security

    Science.gov (United States)

    Paulus, Caroline; Moulin, Vincent; Perion, Didier; Radisson, Patrick; Verger, Loïck

    2017-05-01

    X-ray based systems have been used for decades to screen luggage or cargo to detect illicit material. The advent of energy-sensitive photon-counting x-ray detectors mainly based on Cd(Zn)Te semi-conductor technology enables to improve discrimination between materials compared to single or dual energy technology. The presented work is part of the EUROSKY European project to develop a Single European Secure Air-Cargo Space. "Cargo" context implies the presence of relatively heavy objects and with potentially high atomic number. All the study is conducted on simulations with three different detectors: a typical dual energy sandwich detector, a realistic model of the commercial ME100 multi-energy detector marketed by MULTIX, and a ME100 "Cargo": a not yet existing modified multi-energy version of the ME100 more suited to air freight cargo inspection. Firstly, a comparison on simulated measurements shows the performances improvement of the new multi-energy detectors compared to the current dual-energy one. The relative performances are evaluated according to different criteria of separability or contrast-to-noise ratio and the impact of different parameters is studied (influence of channel number, type of materials and tube voltage). Secondly, performances of multi-energy detectors for overlaps processing in a dual-view system is accessed: the case of orthogonal projections has been studied, one giving dimensional values, the other one providing spectral data to assess effective atomic number. A method of overlap correction has been proposed and extended to multi-layer objects case. Therefore, Calibration and processing based on bi-material decomposition have been adapted for this purpose.

  19. Relationship between CT findings and electroencephalograms of children with cerebral palsy

    International Nuclear Information System (INIS)

    Hirata, Yoshiaki; Nakano, Masao; Soumiya, Kyoichi; Ito, Masamitsu; Asano, Seiji; Tsukimura, Yasuharu.

    1983-01-01

    Electroencephalograms and CT findings of 43 infants with cerebral palsy were evaluated. Nineteen of them (44%) had abnormal findings of CT. The incidences of epileptic attacks and abnormal electroencephalograms were 33% and 84% in each group, respectively, with no differences between a normal-CT group and an abnormal-CT one. In electroencephalograms, positive spikes did not correlate with abnormal CT findings, but abnormal basal waves, particularly, low voltage dysrhythmia did well. Lazy activity also correlated with the abnormal CT findings. (Ueda, J.)

  20. Necrotizing fasciitis : plain radiographic and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Dae; Park, Jeong Hee; Jeon, Hae Jeong; Lim, Jong Nam; Heo, Tae Haeng; Park, Dong Rib [Konkuk Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-11-01

    To evaluate the plain radiographic and CT findings of the necrotizing fasciitis. We retrospectively reviewed the radiologic findings of 4 cases with necrotizing fasciitis. Three cases were proven pathologically. We evaluated pattern and extent of the gas shadows in plain films. CT findings were analysed, with emphasis on : (a) gas pattern, (b) extent, (c) location and involved site, (d) associated focal abscess, and (e) swelling of the adjacent muscles. On plain radiographs, four cases showed streaky or mottled gas densities in the pelvis, three cases in the perineum, one case in the abdomen, and two cases in the thigh. On CT images, gas pattern was mottled and streaky appearance with swelling of the adjacent muscles. Gas shadows located in the extraperitoneal space in four cases, fascial layer in four cases, and subcutaneous layer in four cases. There were gas shadows in pelvic wall, perineum, abdominal wall, buttock, thigh, and scrotum. Focal low density lesion suggestive of focal abscess was not visualized. Plain radiography is useful for early diagnosis of the necrotizing fasciitis and CT is very useful for detection of precise location and extent of the disease. CT is also useful for differentiation of necrotizing fasciitis from focal abscess and cellulitis.

  1. CT findings in ileo-caval thrombosis

    International Nuclear Information System (INIS)

    Harder, T.; Distelmaier, W.; Koester, O.

    1982-01-01

    Thrombosis of a large vein can be demonstrated by CT. The thrombosed vein has a hyperdense lumen, with a somewhat increased diameter which does not opacify after intravenous contrast injection, but which shows a narrow hyperdense margin. Collateral vesels in the pelvic or paravertebral plexus and dilated veins in the abdominal skin are indirect evidence of ileo-caval thrombosis. CT can also demonstrate the cranial extent of a caval thrombosis. Venous thrombosis demonstrated by CT is an important additional finding in the pre-operative examination of the abdomen. (orig.) [de

  2. CT findings in recurrent pyogenic cholangitis

    International Nuclear Information System (INIS)

    Jung, Seung Hye; Lim, Jae Hoon; Ko, Young Tae; Lee, Dong Ho

    1991-01-01

    Recurrent pyogenic cholangitis is characterized clinically by recurrent attacks of right upper abdominal pain, fever and jaundice, and pathologically by chronic inflammation of the bile ducts with or without pigment bile duct stones. We analyzed the CT findings of 33 cases with recurrent pyogenic cholangitis. Twenty-four cases were confirmed by operation, and 9 cases were diagnosed clinically and cholangiographically. The CT findings of recurrent pyogenic cholangitis were dilatation of the intrahepatic ducts (n = 30), dilatation of the extrahepatic ducts (n = 24) intrahepatic stones (n = 16), extrahepatic stones (n = 12), stricture of the bile ducts (n = 10), wall enhancement of the bile ducts (n = 8), gallstones (n = 8), segmental atrophy of the liver (n = 7), pneumobilia (n = 4), abscess (n = 3), and segmental enhancement (n = 1) of the liver. A CT is considered helpful when sectional imaging is needed, but sonographic findings are equivocal or not confirmative; space-occupying lesions complicated with recurrent pyogenic cholangitis: hepatic resection is planned; and imaging guidance is needed for complex drainage procedures

  3. Retrospectively ECG-gated multi-detector row CT of the chest: does ECG-gating improve three-dimensional visualization of the bronchial tree?

    International Nuclear Information System (INIS)

    Schertler, T.; Wildermuth, S.; Willmann, J.K.; Crook, D.W.; Marincek, B.; Boehm, T.

    2004-01-01

    Purpose: To determine the impact of retrospectively ECG-gated multi-detector row CT (MDCT) on three-dimensional (3D) visualization of the bronchial tree and virtual bronchoscopy (VB) as compared to non-ECG-gated data acquisition. Materials and Methods: Contrast-enhanced retrospectively ECG-gated and non-ECG-gated MDCT of the chest was performed in 25 consecutive patients referred for assessment of coronary artery bypass grafts and pathology of the ascending aorta. ECG-gated MDCT data were reconstructed in diastole using an absolute reverse delay of -400 msec in all patients. In 10 patients additional reconstructions at -200 msec, -300 msec, and -500 msec prior to the R-wave were performed. Shaded surface display (SSD) and virtual bronchoscopy (VB) for visualization of the bronchial segments was performed with ECG-gated and non-ECG-gated MDCT data. The visualization of the bronchial tree underwent blinded scoring. Effective radiation dose and signal-to-noise ratio (SNR) for both techniques were compared. Results: There was no significant difference in visualizing single bronchial segments using ECG-gated compared to non-ECG-gated MDCT data. However, the total sum of scores for all bronchial segments visualized with non-ECG-gated MDCT was significantly higher compared to ECG-gated MDCT (P [de

  4. Choroidal osteoma: US and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Hun; Park, Sang Woo [Armed Forces Kwangju Hospital, Kwangju (Korea, Republic of); Kim, Jeong Hun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2003-02-01

    The purpose of this study was to evaluate US and CT features of choroidal osteoma. US and CT scans of seven cases of choroidal osteoma occurring in six patients were retrospectively analyzed. We analysed US and CT findings with particular attention to the location, size, and shape of calcification associated with choroidal osteoma, and sought the possible cause of the tumor, if any. None of six patients had any possible cause related to choroidal osteoma. All of seven cases of choroidal osteoma were manifested as calcified mass which were located in the posterior wall of the eyeball near the juxtapapillary region. Calcification ranged in size from 1 to 2 cm and had curvilinear shape. Both US and CT were equally useful to evaluate choroidal osteoma. By depicting the characteristic calcification, US and CT are useful imaging modalities in evaluating choroidal osteoma.

  5. Validation of multi-detector computed tomography as a non-invasive method for measuring ovarian volume in macaques (Macaca fascicularis).

    Science.gov (United States)

    Jones, Jeryl C; Appt, Susan E; Werre, Stephen R; Tan, Joshua C; Kaplan, Jay R

    2010-06-01

    The purpose of this study was to validate low radiation dose, contrast-enhanced, multi-detector computed tomography (MDCT) as a non-invasive method for measuring ovarian volume in macaques. Computed tomography scans of four known-volume phantoms and nine mature female cynomolgus macaques were acquired using a previously described, low radiation dose scanning protocol, intravenous contrast enhancement, and a 32-slice MDCT scanner. Immediately following MDCT, ovaries were surgically removed and the ovarian weights were measured. The ovarian volumes were determined using water displacement. A veterinary radiologist who was unaware of actual volumes measured ovarian CT volumes three times, using a laptop computer, pen display tablet, hand-traced regions of interest, and free image analysis software. A statistician selected and performed all tests comparing the actual and CT data. Ovaries were successfully located in all MDCT scans. The iliac arteries and veins, uterus, fallopian tubes, cervix, ureters, urinary bladder, rectum, and colon were also consistently visualized. Large antral follicles were detected in six ovaries. Phantom mean CT volume was 0.702+/-SD 0.504 cc and the mean actual volume was 0.743+/-SD 0.526 cc. Ovary mean CT volume was 0.258+/-SD 0.159 cc and mean water displacement volume was 0.257+/-SD 0.145 cc. For phantoms, the mean coefficient of variation for CT volumes was 2.5%. For ovaries, the least squares mean coefficient of variation for CT volumes was 5.4%. The ovarian CT volume was significantly associated with actual ovarian volume (ICC coefficient 0.79, regression coefficient 0.5, P=0.0006) and the actual ovarian weight (ICC coefficient 0.62, regression coefficient 0.6, P=0.015). There was no association between the CT volume accuracy and mean ovarian CT density (degree of intravenous contrast enhancement), and there was no proportional or fixed bias in the CT volume measurements. Findings from this study indicate that MDCT is a valid non

  6. Acute bowel ischemia: CT findings

    International Nuclear Information System (INIS)

    Angelelli, Giuseppe; Scardapane, Arnaldo; Memeo, Maurizio; Stabile Ianora, Amato Antonio; Rotondo, Antonio

    2004-01-01

    Acute bowel ischemia represents one of the most dramatic abdominal emergencies and, despite the fact it is more and more frequently observed in clinical practice, its mortality rate remains very high. In recent years Computed Tomography (CT) has proved to be a valid diagnostic tool in the evaluation of patients with acute abdominal syndrome and in the visualization of early signs of bowel ischemia. This paper reviews the aetiological and pathophysiological aspects as well as a broad spectrum of CT findings of this clinical condition

  7. Systematic implementation of spectral CT with a photon counting detector for liquid security inspection

    Science.gov (United States)

    Xu, Xiaofei; Xing, Yuxiang; Wang, Sen; Zhang, Li

    2018-06-01

    X-ray liquid security inspection system plays an important role in homeland security, while the conventional dual-energy CT (DECT) system may have a big deviation in extracting the atomic number and the electron density of materials in various conditions. Photon counting detectors (PCDs) have the capability of discriminating the incident photons of different energy. The technique becomes more and more mature in nowadays. In this work, we explore the performance of a multi-energy CT imaging system with a PCD for liquid security inspection in material discrimination. We used a maximum-likelihood (ML) decomposition method with scatter correction based on a cross-energy response model (CERM) for PCDs so that to improve the accuracy of atomic number and electronic density imaging. Experimental study was carried to examine the effectiveness and robustness of the proposed system. Our results show that the concentration of different solutions in physical phantoms can be reconstructed accurately, which could improve the material identification compared to current available dual-energy liquid security inspection systems. The CERM-base decomposition and reconstruction method can be easily used to different applications such as medical diagnosis.

  8. CT finding of secondary aorto-enteric fistulae

    International Nuclear Information System (INIS)

    Tacchini, Simona; Nicoletti, Roberto; Ghio, Domenica; Martinenghi, Carlo Maria Andrea; Del Maschio, Alessandro; Chiesa, Roberto

    2005-01-01

    Purpose. The aim of our study was to review CT finding concerning secondary aorto-enteric fistulae (AEF). In particular, we aimed to evaluate signs of contrast medium extravasation from the aortic graft into the bowel (active bleeding), in correlation with clinical and surgical reports. Materials and methods. Clinical and CT findings were retrospectively evaluated in 13 surgically proven cases of AEF. All patients underwent spiral CT examination with biphasic contrast technique, before and 30 and 80 seconds after intravenous injection of 120-150 ml of contrast medium (Ultravist 370; flow rate 2.5-3 ml/sec). Late scans (240 seconds) were also acquired on surgical anastomoses. We used 3 mm (arterial phase) and 5 mm (venous phase slices. Results. At surgery, all patients presented a communication between the bowel and the aortic graft. At CT examination, all 13 patients presented one or more CT signs indicating AEF (perigraft soft tissue, perigraft fluid, ectopic air or bowel wall thickening). Moreover, in 6 out of 13 patients, contrast medium extravasation from the aortic graft into the small bowel (active bleeding) was detected with CT. Detection of active bleeding was possible because CT examinations were performed without oral administration of contrast medium. Conclusions. CT is easily and readily available and provides an accurate evaluation of the aorta and surrounding retroperitoneal tissues. In our study we were able to identify the CT sign of active bleeding in more than a half of the patients with acute gastrointestinal bleeding (66%). Hence, we suggest that patients undergo CT examination without oral contrast medium administration in order to better appreciate the presence of active bleeding [it

  9. Characteristic findings of metrizamide CT cisternography in epidermoids

    International Nuclear Information System (INIS)

    Inoue, H.; Toya, Sh.; Ohtani, M.; Kawase, T.; Takenaka, N.; Okui, Sh.; Miyahara, Y.; Shiga, H.

    1984-01-01

    The characteristic findings of metrizamide CT cisternography in two cases of epidermoid are reported. The main finding was a 'cauliflower-like' appearance and was thought to be caused by the irregular interstices of epidermoids. Metrizamide CT cisternography may be helpful in making a diagnosis of an epidermoid. (Author)

  10. Correctness of multi-detector-row computed tomography for diagnosing mechanical prosthetic heart valve disorders using operative findings as a gold standard

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, I.Chen [Taichung Veterans General Hospital, Department of Radiology, Taichung (China); Institute of Clinical Medicine and Faculty of Medicine, National Yang-Ming University, Taipei (China); Lin, Yung-Kai; Chang, Yen; Wang, Chung-Chi; Hsieh, Shih-Rong; Wei, Hao-Ji; Tsai, Hung-Wen [Taichung Veterans General Hospital, Section of Cardiovascular Surgery, Cardiovascular Center, Taichung (China); Fu, Yun-Ching; Jan, Sheng-Ling [Institute of Clinical Medicine and Faculty of Medicine, National Yang-Ming University, Taipei (China); Taichung Veterans General Hospital, Section of Pediatric Cardiology, Department of Pediatrics, Taichung (China); Wang, Kuo-Yang [Taichung Veterans General Hospital, Section of General Cardiology, Cardiovascular Center, Taichung (China); Chung-Shan Medical University, Department of Medicine, Taichung (China); Chen, Min-Chi; Chen, Clayton Chi-Chang [Taichung Veterans General Hospital, Department of Radiology, Taichung (China); Central Taiwan University of Science and Technology, Department of Radiological Technology, Taichung (China)

    2009-04-15

    The purpose was to compare the findings of multi-detector computed tomography (MDCT) in prosthetic valve disorders using the operative findings as a gold standard. In a 3-year period, we prospectively enrolled 25 patients with 31 prosthetic heart valves. MDCT and transthoracic echocardiography (TTE) were done to evaluate pannus formation, prosthetic valve dysfunction, suture loosening (paravalvular leak) and pseudoaneurysm formation. Patients indicated for surgery received an operation within 1 week. The MDCT findings were compared with the operative findings. One patient with a Bjoerk-Shiley valve could not be evaluated by MDCT due to a severe beam-hardening artifact; thus, the exclusion rate for MDCT was 3.2% (1/31). Prosthetic valve disorders were suspected in 12 patients by either MDCT or TTE. Six patients received an operation that included three redo aortic valve replacements, two redo mitral replacements and one Amplatzer ductal occluder occlusion of a mitral paravalvular leak. The concordance of MDCT for diagnosing and localizing prosthetic valve disorders and the surgical findings was 100%. Except for images impaired by severe beam-hardening artifacts, MDCT provides excellent delineation of prosthetic valve disorders. (orig.)

  11. Development of CT and 3D-CT Using Flat Panel Detector Based Real-Time Digital Radiography System

    International Nuclear Information System (INIS)

    Ravindran, V. R.; Sreelakshmi, C.; Vibin

    2008-01-01

    The application of Digital Radiography in the Nondestructive Evaluation (NDE) of space vehicle components is a recent development in India. A Real-time DR system based on amorphous silicon Flat Panel Detector has been developed for the NDE of solid rocket motors at Rocket Propellant Plant of VSSC in a few years back. The technique has been successfully established for the nondestructive evaluation of solid rocket motors. The DR images recorded for a few solid rocket specimens are presented in the paper. The Real-time DR system is capable of generating sufficient digital X-ray image data with object rotation for the CT image reconstruction. In this paper the indigenous development of CT imaging based on the Realtime DR system for solid rocket motor is presented. Studies are also carried out to generate 3D-CT image from a set of adjacent CT images of the rocket motor. The capability of revealing the spatial location and characterisation of defect is demonstrated by the CT and 3D-CT images generated.

  12. Spectral response of multi-element silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ludewigt, B.A.; Rossington, C.S.; Chapman, K. [Univ. of California, Berkeley, CA (United States)

    1997-04-01

    Multi-element silicon strip detectors, in conjunction with integrated circuit pulse-processing electronics, offer an attractive alternative to conventional lithium-drifted silicon Si(Li) and high purity germanium detectors (HPGe) for high count rate, low noise synchrotron x-ray fluorescence applications. One of the major differences between the segmented Si detectors and the commercially available single-element Si(Li) or HPGe detectors is that hundreds of elements can be fabricated on a single Si substrate using standard silicon processing technologies. The segmentation of the detector substrate into many small elements results in very low noise performance at or near, room temperature, and the count rate of the detector is increased many-fold due to the multiplication in the total number of detectors. Traditionally, a single channel of detector with electronics can handle {approximately}100 kHz count rates while maintaining good energy resolution; the segmented detectors can operate at greater than MHz count rates merely due to the multiplication in the number of channels. One of the most critical aspects in the development of the segmented detectors is characterizing the charge sharing and charge loss that occur between the individual detector strips, and determining how these affect the spectral response of the detectors.

  13. Cardiac imaging using 256-detector row four-dimensional CT. Preliminary clinical report

    International Nuclear Information System (INIS)

    Kido, Teruhito; Kurata, Akira; Higashino, Hiroshi

    2007-01-01

    Along with the increase of detector rows on the z-axis and a faster gantry rotation speed, the spatial and temporal resolutions of the multislice computed tomography (CT) have been improved for noninvasive coronary artery imaging. We investigated the feasibility of the second specification prototype 256-detector row four-dimensional CT for assessing coronary artery and cardiac function. The subjects were five patients with coronary artery disease. Contrast medium (40-60 ml) was intravenously administered at the rate of 3-4 ml/s. The patient's whole heart was scanned for 1.5 s to cover at least one cardiac cycle during breathholding without electrocardiographic gating. Parameters used were 0.5 mm slice thickness, 0.5 s/rotation, 120 Kv, and 350 mA, with a half-scan reconstruction algorithm (temporal resolution 250 ms). Twenty-six transaxial datasets were reconstructed at intervals of 50 ms. The assessability of the coronary arteries in American Heart Association (AHA) segments 1, 2, 3, 5, 6, 7, 9, and 11 was visually evaluated, resulting in 29 of 32 (90.9%) segments being assessable. Functional assessment was also performed using animated movies without banding artifacts in all cases. The 256-detector row four-dimensional CT can assess the coronary artery and cardiac function using data during 1.5 s without banding artifacts. (author)

  14. Localized Castleman's disease: CT and MRI findings

    International Nuclear Information System (INIS)

    Chen Zuhua; Yang Guangzhao

    2008-01-01

    Objective: To study the CT and MRI findings of localized Castleman's disease (LCD). Methods: The CT (n=7) and MRI (n=2) appearance of LCD (n=7) confirmed by pathology and operation were retrospectively analyzed. Results Hyaline-vascular type(n=6) and plasma cell type (n=1) were confirmed by pathology in LCD (n=7). They were located in middle mediastinum (n=2), hilum pulmonis (n=l), posterior mediastinum (n=3), retro-peritoneum (n=1). Hyaline-vascular type focuses in CT scanning were manifested as round shape soft tissue masses, with homogeneous density, integrity envelope, distinct margin, and chaperonage arborizing and spot calcification. Marked persistent enhancement was apparent on contrast CT. MRI findings of hyaline-vascular type (n=2) was slightly isointense or hyperintense on T 1 WI, homogeneous hyperintense on T 2 WI, similar enhancement with CT after contrast. Plasma cell type focus were unhomogeneous density with abnormity necrosis, media and unhomogeneous enhancement after contrast. Conclusion: Marked persistent enhancement of LCD would be helpful to diagnosis and differential diagnosis in Castleman's disease. (authors)

  15. Squalene aspiration pneumonia : thin-section CT and histopathologic findings

    International Nuclear Information System (INIS)

    Lee, Jin Seong; Gong, Gyung Yub; Lim, Tae Hwan

    1998-01-01

    The purpose of this study was to describe the thin-section computed tomography (CT) findings and histopathologic findings of squalene aspiration pneumonia. Thin-section CT scans were obtained from nine patients with proven exogenous lipoid pneumonia resulting from aspiration of squalene (derived from shark liver oil). The condition was diagnosed by biopsy (n=3), bronchoalveolar lavage(n=4), or sputum cytology and clinical history (n=2) of squalene use was confirmed in all patients. Specimens of transbronchial lung biopsy were also reviewed and compared with thin-section CT findings. On the basis of these results, we concluded that squalene aspiration pneumonia can be reliably diagnosed by thin-section CT findings particularly when the appropriate history is known. (author). 19 refs., 3 figs

  16. AN EVALUATION OF THE BASIC CHARACTERISTICS OF A PLASTIC SCINTILLATING FIBRE DETECTOR IN CT RADIATION FIELDS.

    Science.gov (United States)

    Terasaki, Kento; Fujibuchi, Toshioh; Toyoda, Takatoshi; Yoshida, Yutaka; Akasaka, Tsutomu; Nohtomi, Akihiro; Morishita, Junji

    2016-12-01

    The ionisation chamber for computed tomography (CT) is an instrument that is most commonly used to measure the computed tomography dose index. However, it has been reported that the 10 cm effective detection length of the ionisation chamber is insufficient due to the extent of the dose distribution outside the chamber. The purpose of this study was to estimate the basic characteristics of a plastic scintillating fibre (PSF) detector with a long detection length of 50 cm in CT radiation fields. The authors investigated position dependence using diagnostic X-ray equipment and dependencies for energy, dose rate and slice thickness using an X-ray CT system. The PSF detector outputs piled up at a count rate of 10 000 counts ms -1 in dose rate dependence study. With calibration, this detector may be useful as a CT dosemeter with a long detection length except for the measurement at high dose rate. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. CASE SERIES Substantive incidental cardiac findings revealed by ...

    African Journals Online (AJOL)

    For years, the technological limitations inherent in CT imaging of the thorax meant that the heart was an ill-defined and largely ignored. 'space-filler' between the lungs. With the advent of multi-detector CT scanning (MDCT) in the late 1990s, and shortened imaging times, it has now become possible to clearly identify cardiac ...

  18. Adult polysplenia syndrome.CT findings

    International Nuclear Information System (INIS)

    Sebastia, M.C.; Hernandez, D.; Garriga, V.; Alvarez-Castells, A.

    1997-01-01

    We present a case of polysplenia in a 55-year-old patient that was diagnosed incidentally by CT. Chest X-ray disclosed a hooked prominence of the azygos vein over right hilum, left bronchial isomerism and the absence of the inferior vena cava in an X-ray of the right side. The abdominal CT findings included multiple spleens and stomach in upper right quadrant, centrally located liver and gallbladder, intestinal malrotation, interrupted inferior vena cava continued in the azygos system, and short pancreas. Echocardiography revealed mitral stenosis not associated with cardiac malformation. (Author)

  19. Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE

    CERN Document Server

    Anderson, NG; Firsching, M; de Ruiter, N; Schleich, N; Butzer, J S; Cook, N J; Grasset, R; Campbell, M; Scott, N J A; Anderson, N G

    2010-01-01

    Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 A mu A). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct f...

  20. Chest CT findings of toxocariasis: Correlation with laboratory results

    International Nuclear Information System (INIS)

    Hur, J.H.; Lee, I.J.; Kim, J.-H.; Kim, D.-G.; Hwang, H.J.; Koh, S.H.; Lee, K.

    2014-01-01

    Aim: To assess the relationship between chest computed tomography (CT) findings of patients with toxocariasis and levels of serological markers. Materials and methods: A total of 38 cases of patients diagnosed with toxocariasis by enzyme-linked immunosorbent assay (ELISA), CT, and serological markers were retrospectively reviewed. The presence of nodule with or without ground-glass opacity (GGO) halo, consolidation, focal GGO, pleural effusion, and lymphadenopathy at chest CT were evaluated. Statistical analysis was performed with the Fisher's exact test. Results: The most common chest CT findings were nodule (n = 12, 31.6%) and focal GGO (n = 12, 31.6%). In patients with normal eosinophil levels, focal GGO (n = 9, 37.5%) was the most common finding. In contrast, nodule with a GGO halo (n = 7, 50%) was the most common finding in the eosinophilia group. Nodule with a GGO halo was more common in the eosinophilia group, with a statistically significant difference (p = 0.017). Nodule was more common in the eosinophilia group, and focal GGO was more common in the normal eosinophil group. Conclusion: The most common chest CT findings in toxocariasis were nodule with or without GGO halo, and focal GGO. In the eosinophilia group, nodule with a GGO halo was significantly more frequent. Other CT findings did not show a statistically significant relationship with serological markers

  1. Scanning and contrast enhancement protocols for multi-slice CT in evaluation of the upper abdomen

    International Nuclear Information System (INIS)

    Awai, Kazuo; Onishi, Hiromitsu; Takada, Koichi; Yamaguchi, Yasuo; Eguchi, Nobuko; Hiraishi, Kumiko; Hori, Shinichi

    2000-01-01

    The advent of multi-slice CT is one of the quantum leaps in computed tomography since the introduction of helical CT. Multi-slice CT can rapidly scan a large longitudinal (z-axis) volume with high longitudinal resolution and low image artifacts. The rapid volume coverage speed of multi-slice CT can increase the difficulty in optimizing the delay time between the beginning of contrast material injection and the acquisition of images and we need accurate knowledge about optimal temporal window for adequate contrast enhancement. High z-axis resolution of multi-slice can improve the quality of three-dimensional images and MPR images and we must select adequate slice thickness and slice intervals in each case. We discuss basic considerations for adequate contrast enhancement and scanning protocols by multi-slice CT scanner in the upper abdomen. (author)

  2. Pediatric renal leukemia: spectrum of CT imaging findings

    International Nuclear Information System (INIS)

    Hilmes, Melissa A.; Dillman, Jonathan R.; Mody, Rajen J.; Strouse, Peter J.

    2008-01-01

    The kidneys are a site of extramedullary leukemic disease that can be readily detected by CT. To demonstrate the spectrum of CT findings in children with renal leukemic involvement. Twelve children were identified retrospectively as having renal leukemic involvement by contrast-enhanced CT of the abdomen. Contrast-enhanced CT images through the kidneys of each patient were reviewed by two pediatric radiologists. Pertinent imaging findings and renal lengths were documented. The electronic medical record was accessed to obtain relevant clinical and pathologic information. Five patients with renal leukemic involvement presented with multiple bilateral low-attenuation masses, while three patients demonstrated large areas of wedge-shaped and geographic low attenuation. Four other patients presented with unique imaging findings, including a solitary unilateral low-attenuation mass, solitary bilateral low-attenuation masses, multiple bilateral low-attenuation masses including unilateral large conglomerate masses, and bilateral areas of ill-defined parenchymal low attenuation. Two patients showed unilateral nephromegaly, while eight other patients showed bilateral nephromegaly. Two patients had normal size kidneys. Two patients had elevated serum creatinine concentrations at the time of imaging. Renal leukemic involvement in children can present with a variety of CT imaging findings. Focal renal abnormalities as well as nephromegaly are frequently observed. Most commonly, renal leukemic involvement does not appear to impair renal function. (orig.)

  3. Pediatric renal leukemia: spectrum of CT imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Hilmes, Melissa A. [University of Michigan Health System, C.S. Mott Children' s Hospital, Section of Pediatric Radiology, Ann Arbor, MI (United States); Vanderbilt University Children' s Hospital, Section of Pediatric Radiology, Nashville, TN (United States); Dillman, Jonathan R. [University of Michigan Health System, C.S. Mott Children' s Hospital, Section of Pediatric Radiology, Ann Arbor, MI (United States); University of Michigan Health System, Department of Radiology, Ann Arbor, MI (United States); Mody, Rajen J. [University of Michigan Health System, C.S. Mott Children' s Hospital, Division of Pediatric Hematology-Oncology and Bone Marrow Transplantation, Ann Arbor, MI (United States); Strouse, Peter J. [University of Michigan Health System, C.S. Mott Children' s Hospital, Section of Pediatric Radiology, Ann Arbor, MI (United States)

    2008-04-15

    The kidneys are a site of extramedullary leukemic disease that can be readily detected by CT. To demonstrate the spectrum of CT findings in children with renal leukemic involvement. Twelve children were identified retrospectively as having renal leukemic involvement by contrast-enhanced CT of the abdomen. Contrast-enhanced CT images through the kidneys of each patient were reviewed by two pediatric radiologists. Pertinent imaging findings and renal lengths were documented. The electronic medical record was accessed to obtain relevant clinical and pathologic information. Five patients with renal leukemic involvement presented with multiple bilateral low-attenuation masses, while three patients demonstrated large areas of wedge-shaped and geographic low attenuation. Four other patients presented with unique imaging findings, including a solitary unilateral low-attenuation mass, solitary bilateral low-attenuation masses, multiple bilateral low-attenuation masses including unilateral large conglomerate masses, and bilateral areas of ill-defined parenchymal low attenuation. Two patients showed unilateral nephromegaly, while eight other patients showed bilateral nephromegaly. Two patients had normal size kidneys. Two patients had elevated serum creatinine concentrations at the time of imaging. Renal leukemic involvement in children can present with a variety of CT imaging findings. Focal renal abnormalities as well as nephromegaly are frequently observed. Most commonly, renal leukemic involvement does not appear to impair renal function. (orig.)

  4. Laryngotracheobronchial papillomatosis: chest CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Fortes, Helena Ribeiro; Zanetti, Glaucia; Marchiori, Edson, E-mail: edmarchiori@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Ranke, Felipe Mussi von [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Escuissato, Dante Luiz [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Clinica Medica; Araujo Neto, Cesar Augusto [Universidade Federal da Bahia (UFBA), Salvador (Brazil). Dept. de Medicina e Apoio Diagnostico; Hochhegger, Bruno [Universidade Federal de Ciencias da Saude de Porto Alegre (UFCSPA), RS (Brazil). Diagnostico por Imagem; Irion, Klaus Loureiro [Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool (United Kingdom); Souza, Carolina Althoff [Dept. of Diagnostic Imaging, The Ottawa Hospital, University of Ottawa, Ontario (Canada)

    2017-07-15

    To evaluate the findings on chest CTs in 16 patients (8 men and 8 women) with laryngotracheobronchial papillomatosis. Methods: This was a retrospective study involving patients ranging from 2 to 72 years of age. The evaluation of the CT scans was independently performed by two observers, and discordant results were resolved by consensus. The inclusion criteria were presence of abnormalities on the CT scans, and the diagnosis was confirmed by anatomopathological examination of the papillomatous lesions. Results: The most common symptoms were hoarseness, cough, dyspnea, and recurrent respiratory infections. The major CT findings were nodular formations in the trachea, solid or cavitated nodules in the lung parenchyma, air trapping, masses, and consolidation. Nodular formations in the trachea were observed in 14 patients (87.5%). Only 2 patients had lesions in lung parenchyma without tracheal involvement. Only 1 patient had no pulmonary dissemination of the disease, showing airway involvement only. Solid and cavitated lung nodules were observed in 14 patients (87.5%) and 13 (81.2%), respectively. Masses were observed in 6 patients (37.5%); air trapping, in 3 (18.7%); consolidation in 3 (18.7%); and pleural effusion, in 1 (6.3%). Pulmonary involvement was bilateral in all cases. Conclusions: The most common tomography findings were nodular formations in the trachea, as well as solid or cavitated nodules and masses in the lung parenchyma. Malignant transformation of the lesions was observed in 5 cases. (author)

  5. {sup 18}F-FDG PET/CT and contrast-enhanced CT findings of pulmonary cryptococcosis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Si-yun, E-mail: wang_shuxia@outlook.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Chen, Gang, E-mail: cgggh@outlook.com [Department of Thoracic Surgery, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Luo, Dong-lan, E-mail: 695532870@qq.com [Department of Pathology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Shao, Dan, E-mail: shaodan501@outlook.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Liu, En-tao, E-mail: GDGH2015@gmail.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Sun, Taotao, E-mail: sunmoodsdaisy@bjmu.edu.cn [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Wang, Shu-Xia, E-mail: wsyggh@outlook.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China)

    2017-04-15

    Purpose: Pulmonary cryptococcosis is an uncommon cause of pulmonary nodules in non-AIDS patients. This study reports the {sup 18}F-fluorodeoxyglucose-positron emission tomography ({sup 18}F-FDG PET/CT) and contrast-enhanced CT (CE-CT) findings of 42 patients with pulmonary cryptococcosis. Materials and methods: A retrospective review of the {sup 18}F-FDG PET/CT and CE-CT findings of 42 patients with histologically proven pulmonary cryptococcosis was conducted. All patients underwent PET/CT and CE-CT in the same session. The CT diagnosis was based on the location, morphological features, and enhancement of lesions. The PET/CT findings were recorded, and clinical data and surgical and histopathological findings were collected. Results: The results of the PET scans revealed that 37 (88%) of 42 patients showed higher FDG uptake, and 5 (12%) patients demonstrated lower FDG uptake than the mediastinal blood pool. The maximum standardized uptake value (SUV) of pulmonary cryptococcosis ranged from 1.4 to 13.0 (average: 5.7 ± 3.3, median 4.9). A single nodular pattern was the most prevalent pattern observed and was found in 29 (69%) patients. This pattern was followed by scattered nodular (n = 4, 10%), clustered nodular (n = 3, 7%), mass-like (n = 3, 7%), and bronchopneumonic (n = 3, 7%) patterns. The most frequent pattern of immunocompetent patients was the single nodular pattern (29 of 33, 88%). Immunocompromised patients most frequently pattern exhibited mass-like (3 of 9, 33%) and bronchopneumonic (3 of 9, 33%) patterns. Conclusion: Pulmonary cryptococcosis most commonly appears as single nodules in immunocompetent patients. Mass-like and bronchopneumonic patterns were common in immunocompromised patients. In 88% of patients, lung lesions showed high FDG uptake, thus mimicking a possible malignant condition.

  6. CT findings of the patients with bronchial asthma

    International Nuclear Information System (INIS)

    Katagiri, Shiro; Ohshima, Kazuki; Ohsawa, Takehiko.

    1996-01-01

    CT scans were obtained in 45 patients with bronchial asthma including 23 patients during asthmatic attack. CT findings were as follows. 1) In all cases, thickening of bronchial wall throughout from central to peripheral bronchi and without tapering and/or slight swelling of bronchovascular bundles were observed. 2) Characteristics findings in 23 patients with asthmatic attack, lobular and multilobular high attenuation area were observed in 17 patients (74%) and nonhomogeneous attenuation in lung fields were noticed in 13 patients (57%). 3) Multiple centrilobular sized high attenuation area were observed in 23 patients, but it was difficult to differenciation whether these findings were due to tiny nodules or to small vessels. In conclusion, further studies are needed to know which pathomorphological and/or pathophysiological conditions are underlying these CT findings. (author)

  7. Craniofacial and temporal bone CT findings in cleidocranial dysplasia

    International Nuclear Information System (INIS)

    Gonzalez, Guido E.; Caruso, Paul A.; Curtin, Hugh D.; Small, Juan E.; Jyung, Robert W.; Troulis, Maria J.

    2008-01-01

    Cleidocranial dysplasia (CCD) is a multistructural polyostotic genetic disorder that results from mutation of the CBFA1 gene. Hearing loss is a frequent finding in CCD. We describe the CT craniofacial findings in CCD and provide a comprehensive discussion of the CT temporal bone findings in these patients. (orig.)

  8. A high-throughput, multi-channel photon-counting detector with picosecond timing

    Science.gov (United States)

    Lapington, J. S.; Fraser, G. W.; Miller, G. M.; Ashton, T. J. R.; Jarron, P.; Despeisse, M.; Powolny, F.; Howorth, J.; Milnes, J.

    2009-06-01

    High-throughput photon counting with high time resolution is a niche application area where vacuum tubes can still outperform solid-state devices. Applications in the life sciences utilizing time-resolved spectroscopies, particularly in the growing field of proteomics, will benefit greatly from performance enhancements in event timing and detector throughput. The HiContent project is a collaboration between the University of Leicester Space Research Centre, the Microelectronics Group at CERN, Photek Ltd., and end-users at the Gray Cancer Institute and the University of Manchester. The goal is to develop a detector system specifically designed for optical proteomics, capable of high content (multi-parametric) analysis at high throughput. The HiContent detector system is being developed to exploit this niche market. It combines multi-channel, high time resolution photon counting in a single miniaturized detector system with integrated electronics. The combination of enabling technologies; small pore microchannel plate devices with very high time resolution, and high-speed multi-channel ASIC electronics developed for the LHC at CERN, provides the necessary building blocks for a high-throughput detector system with up to 1024 parallel counting channels and 20 ps time resolution. We describe the detector and electronic design, discuss the current status of the HiContent project and present the results from a 64-channel prototype system. In the absence of an operational detector, we present measurements of the electronics performance using a pulse generator to simulate detector events. Event timing results from the NINO high-speed front-end ASIC captured using a fast digital oscilloscope are compared with data taken with the proposed electronic configuration which uses the multi-channel HPTDC timing ASIC.

  9. A high-throughput, multi-channel photon-counting detector with picosecond timing

    International Nuclear Information System (INIS)

    Lapington, J.S.; Fraser, G.W.; Miller, G.M.; Ashton, T.J.R.; Jarron, P.; Despeisse, M.; Powolny, F.; Howorth, J.; Milnes, J.

    2009-01-01

    High-throughput photon counting with high time resolution is a niche application area where vacuum tubes can still outperform solid-state devices. Applications in the life sciences utilizing time-resolved spectroscopies, particularly in the growing field of proteomics, will benefit greatly from performance enhancements in event timing and detector throughput. The HiContent project is a collaboration between the University of Leicester Space Research Centre, the Microelectronics Group at CERN, Photek Ltd., and end-users at the Gray Cancer Institute and the University of Manchester. The goal is to develop a detector system specifically designed for optical proteomics, capable of high content (multi-parametric) analysis at high throughput. The HiContent detector system is being developed to exploit this niche market. It combines multi-channel, high time resolution photon counting in a single miniaturized detector system with integrated electronics. The combination of enabling technologies; small pore microchannel plate devices with very high time resolution, and high-speed multi-channel ASIC electronics developed for the LHC at CERN, provides the necessary building blocks for a high-throughput detector system with up to 1024 parallel counting channels and 20 ps time resolution. We describe the detector and electronic design, discuss the current status of the HiContent project and present the results from a 64-channel prototype system. In the absence of an operational detector, we present measurements of the electronics performance using a pulse generator to simulate detector events. Event timing results from the NINO high-speed front-end ASIC captured using a fast digital oscilloscope are compared with data taken with the proposed electronic configuration which uses the multi-channel HPTDC timing ASIC.

  10. CT findings of tuberculous lymphadenifis in parotid gland

    International Nuclear Information System (INIS)

    Wang Changfu; Wang Binjie; Zhang Heping; Jin Haiying; Nie Peng; Chang Liang; Wei Haigang; Zou Ling

    2008-01-01

    Objective: To analyze the CT findings of tuberculous lymphadenitis in parotid gland, so as to improve the diagnostic accuracy of tuberculosis of parotid gland. Methods: Nine cases with tuberculous lymphadenitis in parotid gland confirmed by surgical pathology and acid-fast bacilli after preoperative spiral CT plain scan and two phases dynamic enhancement scan were retrospectively analyzed. Imaging findings of CT were reviewed and compared with surgical pathology. Results: Seven of the 9 cases of tuberculosis of the parotid gland occurred in the left side, and 2 in the right side, and superficial lobe involvement occurred in 8 cases and deep lobe in 1 case. The lesion was classified as tumour type (8 cases) and infiltration type (1 case). In turnout type, the number of lesion was from 1 to 4, and the size was from 2.7 to 5.3 cm in diameter. One case of infiltration type measured 3.4 cm in diameter. On CT plain scan, the lesions showed homogeneous slight high-density with regular edge in 5 cases and irregular low-density in 4 cases, and 2 of them with partly blurred edge. On CT enhanced scan, uniform moderate enhancement was seen in 3 cases, circular enhancement in 4 cases, inhomogeneous enhancement in 1 case, and lace-like enhancement in 1 case. Local infiltration occurred in 6 cases. Lymphadenovarix in the same side of lesion occurred in 2 cases. Conclusion: CT findings of tuberculous lymphadenitis in parotid gland present diversification, which correlate well with pathological changes. Understanding of characteristic CT findings of tuberculous lymphadenitis in parotid gland is helpful for differential diagnosis, but final diagnosis still depends on pathology and acid-fast bacilli. (authors)

  11. Diagnostic value of multi-slice spiral CT for atlantoaxial spine injuries in children

    International Nuclear Information System (INIS)

    Xia Chengde; Qin Hongwei; Li Junhong

    2009-01-01

    Objective: To evaluate the diagnostic value of multi-slice spiral CT (MSCT) for the atlantoaxial spine injuries in children. Methods: The CT findings of 21 cases with the atlantoaxial spine injuries in children were reviewed retrospectively. Results: Fractures of dens occurred in 4 cases, isolated atlantoaxial dislocation in 15 cases, subluxation of the C2/3 right vertebra facet in 1 and atlanto-occipital subluxation in 1. CT diagnosis was correct in all cases. And plain film diagnosis was correct ia 13. Conclusion: MSCT could clearly demonstrate the fractures and dislocations of the atlantoaxial spine injuries in children and correctly determine the type of the atlantoaxial spine injuries in children, MSCT is the modality of choice in diagnosis of the atlantoaxial spine injuries in children and should be performed routinely. (authors)

  12. Mixed connective tissue disease associated with noted pulmonary CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Souji; Tsukada, Atsuko; Furuya, Tatsutaka

    1984-10-01

    CT was performed in a 56-year-old woman with mixed connective tissue disease (MCTD). Much more definitive pulmonary findings were obtained by CT than by the conventional chest x-ray examination and pulmonary function test. CT findings disclosed pulmonary lesions extremely similar to those in cases of progressive systemic sclerosis. Pulmonary CT was considered useful in examining pulmonary lesions for MCTD.

  13. CT findings in abdominal actinomycosis

    International Nuclear Information System (INIS)

    Lee, In Jae; Ha, Hyun Kwon; Lee, Moon Gyu; Kim, Pyo Nyun; Auh, Yong Ho

    1999-01-01

    Abdominal actinomycosis is a chronic, progressive, suppurative disease with a favorable response to intravenous treatment with penicillin. In many instances, however, its clinical and radiological findings may overlap with those of other inflammatory and neoplastic conditions, and the familiarity with the various radiological features can thus avoid diagnostic delays. The purpose of this paper is to describe and discuss the CT findings of abdominal actinomycosis

  14. Added value of integrated circuit detector in head CT: objective and subjective image quality in comparison to conventional detector design.

    Science.gov (United States)

    Korn, Andreas; Bender, Benjamin; Spira, Daniel; Schabel, Christoph; Bhadelia, Rafeeque; Claussen, Claus; Ernemann, Ulrike; Brodoefel, Harald

    2014-12-01

    A new computed tomography (CT) detector with integrated electric components and shorter conducting pathways has recently been introduced to decrease system inherent electronic noise. The purpose of this study was to assess the potential benefit of such integrated circuit detector (ICD) in head CT by comparing objective and subjective image quality in low-dose examinations with a conventional detector design. Using a conventional detector, reduced-dose noncontrast head CT (255 mAs; effective dose, 1.7 mSv) was performed in 25 consecutive patients. Following transition to ICD, 25 consecutive patients were scanned using identical imaging parameters. Images in both groups were reconstructed with iterative reconstruction (IR) and filtered back projection (FBP) and assessed in terms of quantitative and qualitative image quality. Acquisition of head CT using ICD increased signal-to-noise ratio of gray and white matter by 14% (10.0 ± 1.6 vs. 11.4 ± 2.5; P = .02) and 17% (8.2 ± 0.8 vs. 9.6 ± 1.5; P = .000). The associated improvement in contrast-to-noise ratio was 12% (2.0 ± 0.5 vs. 2.2 ± 0.6; P = .121). In addition, there was a 51% increase in objective image sharpness (582 ± 85 vs. 884.5 ± 191; change in HU/Pixel; P < .000). Compared to standard acquisitions, subjective grading of noise and overall image quality scores were significantly improved with ICD (2.1 ± 0.3 vs. 1.6 ± 0.3; P < .000; 2.0 ± 0.5 vs. 1.6 ± 0.3; P = .001). Moreover, streak artifacts in the posterior fossa were substantially reduced (2.3 ± 0.7 vs. 1.7 ± 0.5; P = .004). At the same radiation level, acquisition of head CT with ICD achieves superior objective and subjective image quality and provides potential for significant dose reduction. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

  15. Evaluation of hepatic alveolar echinococcosis with multi-slices spiral CT

    International Nuclear Information System (INIS)

    Liu Wenya; Lou Jianru; Xing Yan; Wang Jing; Wang Haitao

    2005-01-01

    Objective: To analyze the multi-slices spiral CT (MSCT) findings of hepatic alveolar echinococcosis (HAE), and to evaluate the value of MSCT for diagnosis of HAE. Methods: Twenty-six cases with HAE were scanning by MSCT. The raw data were transmitted to advanced workstation for reconstruction imaging. Correlated studies were made between the CT features and pathology or other imaging results. Results: Altogether 28 lesions were detected. They all revealed as heterogeneous hypodense mass with ill-defined boundary in plain CT but were easily being distinguished from surrounding parenchyma after contrast medium injection. Characteristics of the lesions include different amount of calcification (26/26), liquefied necrosis in center area (20/26), peripheral lacunae or alveolar signs (15/26 ), compensatory hypertrophy of healthy hepatic part (18/26) and the retraction in the involved hepatic lobe or segment (12/26). The lesions that located at or extended to hepatic hilum caused dilatation of intra-hepatic biliary ducts (9/26), splenomegaly (12/26 ), and ascites (1/26). MSCT angiography (CTA) depicted signs of abnormalities of hepatic vessels such as compression, displacement, encasement and occlusion. Compared with findings of operation, the sensitivity, specificity and positive prediction value of CTA for evaluating the hepatic artery system disorders were 88%, 96% and 93%, respectively; and for portal venous system were 95%, 100% and 95%, respectively; while for hepatic venous system were 96%, 86% and 96%, respectively. Conclusion: MSCT is able to comprehensive display the CT features and vessels complication of HAE. It provides reliable imaging for both accuracy diagnosis and proper treatment of the disease. (authors)

  16. Endobronchial metastasis: CT findings and its usefulness in bronchoscopic correlation

    International Nuclear Information System (INIS)

    Ko, Ji Ho; Jung, Gyoo Sik; Kim, Seong Min; Huh Jin Do; Joh, Young Duk; Jang, Tae Weon

    2000-01-01

    To evaluate the CT findings of bronchial abnormalities in patients with endobronchial metastasis from extrapulmonary tumors, and to correlate these with the bronchoscopic findings. The authors retrospectively reviewed the CT and bronchoscopic findings of 17 patients (M:F =3D 9:8; mean age, 56 years) with histologically proven endobronchial metastasis from extrapulmonary primary tumors. Carcinoma of the uterine cervix (n=3D5) was the most common primary site for endobronchial metastasis. CT findings of bronchial abnormalities with associated peribronchial and lung parenchymal lesions were analyzed and compared with the bronchoscopic findings. Among the 17 patients, 20 sites of bronchial abnormalities were visualized bronchoscopically. CT findings of bronchial abnormalities were smooth narrowing (n=3D11), occlusion (n=3D3), intraluminal mass (n=3D4), and normal (n=3D2). Peribronchial lesions (lymph node enlargement or parenchymal mass) were found in 12 cases. Bronchoscopy revealed bronchial narrowing due to a mucosal nodule or intraluminal polypoid mass in 16 cases, and total obstruction of the bronchus in four. With regard to the identification of bronchial abnormalities, the findings of CT and of bronchoscopy agreed in 17 cases and disagreed in three. While bronchoscopy was advantageous for detecting early mucosal abnormality, CT effectively evaluated the extent of a lesion beyond the stenosis or bronchial obstruction. CT was also useful for predicting the causes of bronchial abnormalities. CT is relatively accurate in evaluating bronchial abnormalities, and in patients with endobronchial metastases may be used as a complementary procedure to bronchoscopy for evaluating the extent of the lesion. (author)

  17. Mixed connective tissue disease associated with noted pulmonary CT findings

    International Nuclear Information System (INIS)

    Yamazaki, Souji; Tsukada, Atsuko; Furuya, Tatsutaka

    1984-01-01

    CT was performed in a 56-year-old woman with mixed connective tissue disease (MCTD). Much more definitive pulmonary findings were obtained by CT than by the conventional chest x-ray examination and pulmonary function test. CT findings disclosed pulmonary lesions extremely similar to those in cases of progressive systemic sclerosis. Pulmonary CT was considered useful in examining pulmonary lesions for MCTD. (Namekawa, K.)

  18. In vitro evaluation of 56 coronary artery stents by 256-slice multi-detector coronary CT

    International Nuclear Information System (INIS)

    Steen, Henning; Andre, Florian; Korosoglou, Grigorios; Mueller, Dirk; Hosch, Waldemar; Kauczor, Hans-Ulrich; Giannitsis, Evangelos; Katus, Hugo A.

    2011-01-01

    Objective: We sought to investigate stent lumen visibility of 56 coronary stents with the newest 256-multi-slice-CT (256-MDCT) technology for different reconstruction algorithms in an in vitro model. Background: Early identification of in-stent restenosis (ISR) is important to avoid recurrent ischemia and prevent acute myocardial infarction (AMI). Since angiography has the disadvantage of high costs and its invasiveness, MDCT could be a convenient and safe non-invasive alternative for detection of ISR. Material and methods: Percentages of in-stent lumen diameter and in-stent signal attenuation (measured as contrast-to-noise ratio (CNR)) of 56 coronary stents (group A ≤2.5 mm; group B = 2.75-3.0 mm; group C = 3.5-4.0 mm) were evaluated in a coronary vessel in vitro phantom (iodine-filled plastic tubes) employing four different reconstruction algorithms (XCD, CC, CD, XCB) on a novel 256-MDCT (Philips-iCT, collimation = 128 mm x 0.625 mm; rotation time = 270 ms; tube current = 800 mA s with 120 kV). Analysis was conducted with the semi-automatical full-width-at-half-maximum (FWHM) method. P-values 60% for group C stents was significantly larger and CNR was significantly lower (both p 3.0 mm when analysed with cardio-dedicated sharp kernels, although clinical studies corroborating this claim should be performed. However, stents ≤3.0 mm reconstructed by soft kernels revealed insufficient in-stent lumen visualisation and should not be used in clinical practice. Further improvements in spatial and temporal image resolution as well as reductions of radiation exposure and image noise have to be accomplished for the ambitious goal of characterising both CT coronary artery anatomy and in-stent lumen.

  19. Evaluation of image quality and radiation dose at prospective ECG-triggered axial 256-slice multi-detector CT in infants with congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Mei-ping; Liang, Chang-hong; Zhao, Zhen-jun; Liu, Hui; Li, Jing-lei; Zhang, Jin-e; Cui, Yan-hai; Yang, Lin; Liu, Qi-shun [Guangdong Academy of Medical Sciences, Guangdong General Hospital, Department of Radiology, Guangzhou (China); Ivanc, Thomas B.; Vembar, Mani [Philips Healthcare, CT Clinical Science, Highland Heights, OH (United States)

    2011-07-15

    There are a limited number of reports on the technical and clinical feasibility of prospective electrocardiogram (ECG)-gated multi-detector computed tomography (MDCT) in infants with congenital heart disease (CHD). To evaluate image quality and radiation dose at weight-based low-dose prospectively gated 256-slice MDCT angiography in infants with CHD. From November 2009 to February 2010, 64 consecutive infants with CHD referred for pre-operative or post-operative CT were included. All were scanned on a 256-slice MDCT system utilizing a low-dose protocol (80 kVp and 60-120 mAs depending on weight: 60 mAs for {<=}3 kg, 80 mAs for 3.1-6 kg, 100 mAs for 6.1-10 kg, 120 mAs for 10.1-15 kg). No serious adverse events were recorded. A total of 174 cardiac deformities, confirmed by surgery or heart catheterization, were studied. The sensitivity of MDCT for cardiac deformities was 97.1%; specificity, 99.4%; accuracy, 95.9%. The mean heart rate during scan was 136.7 {+-} 14.9/min (range, 91-160) with a corresponding heart rate variability of 2.8 {+-} 2.2/min (range, 0-8). Mean scan length was 115.3 {+-} 11.7 mm (range, 93.6-143.3). Mean volume CT dose index, mean dose-length product and effective dose were 2.1 {+-} 0.4 mGy (range, 1.5-2.8), 24.7 {+-} 5.9 mGy.cm (range, 14.7-35.8) and 1.6 {+-} 0.3 mSv (range, 1.1-2.5), respectively. Diagnostic-quality images were achieved in all cases. Satisfactory diagnostic quality for visualization of all/proximal/distal coronary artery segments was achieved in 88.4/98.8/80.0% of the scans. Low-dose prospectively gated axial 256-slice CT angiography is a valuable tool in the routine clinical evaluation of infants with CHD, providing a comprehensive three-dimensional evaluation of the cardiac anatomy, including the coronary arteries. (orig.)

  20. CT findings in patient with skull fractures

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Han Gi; Suh, Won Hyuck [Korea University College of Medicine, Seoul (Korea, Republic of)

    1988-12-15

    CT scan has been inevitable method for patient with head trauma. CT scans of 94 cases, which were confirmed skull fracture by plain film, were reviewed for better and useful dealing of CT. The results were as follows: 1. Car accident was the most frequent cause of head injury. 2. No evidence of intracranial abnormality in CT scan of skull fractures on plane film was 45.7%, and alert mentality was 46.8% of skull fracture on skull fracture on simple film. 3. Detection rate on CT scan to skull fractures was 27.7%, but detection rate to depression fractures of skull fracture was 70.2%. 4. Mortality rate of patients with skull fracture was 10.6%. 5. Associated CT findings were pneumocephalus on CT scan 3.2%, contusion of edema 4.2%, epidural hematoma 16.0%, subdural hematoma 17.0%, subdural hygroma 2.1%, intracerebral hemorrhage 4.9%, and subarachnoid hemorrhage 2.0%.

  1. The role of multi-detector CT angiography in surgical planning for congenital cervicothoracic kyphoscoliosis: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun; Choi, Won Gyu; Shin, Ho Dong; Hwang, Byeong Wook; Lee, Sang Jin; Lee, Sang Ho [Busan Wooridul Spine Hospital, Busan (Korea, Republic of)

    2008-01-15

    Surgical correction of a cervicothoracic deformity is difficult with a potential risk of vascular injury. Comprehensive preoperative vascular evaluation is important for safe and successful surgery. The use of multi-detector computed tomography angiography (MDCTA) allows a combined display of vascular and osseous structures of the musculoskeletal system. However, no clinical reports have described the use of MDCTA for surgical planning of anterior cervicothoracic surgery in patients with vascular malformation. The case of a 7-year-old girl with congenital cervicothoracic kyphoscoliosis who underwent preoperative MDCTA evaluation and successful correction is presented in this report.

  2. Radiofrequency ablation of rabbit liver. Correlation between dual CT findings and pathological findings

    International Nuclear Information System (INIS)

    Tsuda, Masashi; Rikimaru, Yuya; Saito, Haruo; Ishibashi, Tadashi; Takahashi, Shyoki; Miyachi, Hideo; Yamada, Syogo

    2002-01-01

    The purpose of this study was to present the time-related imaging findings and correlative pathologic findings of radiofrequency pulse-irradiated regions of the liver. Radiofrequency (RF) ablation was performed in 22 rabbit livers with 15-gauge RF probes inserted percutaneously. Regions were imaged with dual-phase CT at 3 days (n=6), 2 weeks (n=6), 4 weeks (n=6), and 12 weeks (n=4) after RF ablation. At 3 days, the regions showed a two-zone structure on plain CT and peripheral enhancement. The regions presented a three-zone structure on pathological study. Hepatocytes appeared as acidophilic bodies, and nuclei were pyknotic at the inner necrotic zone. The middle whitish zone showed enlarged sinusoids. The marginal zone was a regenerative band. At 2 weeks, the two-zone structure was obscured on unenhanced CT. The region showed a two-zone structure on pathological study. At the inner zone, acidophilic degeneration had progressed, however, cell structure remained. The marginal zone showed fibrous tissue bundles. At 12 weeks, the region was obscured on plain CT. Nuclei and cell structures had disappeared almost completely at the inner zone. Collagen fiber had replaced the marginal zone. Zone structural CT findings reflect the pathological findings and time-related changes after RF ablation. Peripheral enhancement in the arterial phase reflects the granulation tissue layer, and its time-related decrease reflects replacement by fibrous tissue. (author)

  3. The CT-PPS project detector hardware and operational experience

    CERN Document Server

    Ravera, Fabio

    2017-01-01

    The CMS-TOTEM Precision Proton Spectrometer allows extending the LHC physics program by measuring protons in the very forward regions of CMS. Tracking and timing detectors have been installed along the beam pipe at $\\sim 210$~m from the CMS interaction point on both sides of the LHC tunnel. The tracking system consists of a station of silicon strip detectors and one of silicon pixel detectors on each side. The latter is composed of six planes of 3D silicon pixel sensors bump-bonded to the PSI46dig ROC developed for the CMS Phase I Pixel Tracker upgrade. A track resolution of $\\sim 10$~$\\mu$m is obtained. The future goal is to replace the present strip stations with pixel ones in order to ensure better multi-track reconstruction. Each timing station is made of three planes of diamond detectors and one plane equipped with an Ultra-Fast Silicon Detector (UFSD). A timing resolution of a few tens of picoseconds can be achieved with the present detector; a large R\\&D effort is ongoing to reach the $10$~ps targ...

  4. Analysis of discrepancy between neurologic findings and CT findings in 60 patients with herniated nucleus pulposus

    International Nuclear Information System (INIS)

    Lee, Hyun; Kim, Kab Tae; Sol, Chang Hyo; Kim, Byung Soo

    1987-01-01

    The herniated nucleus pulposus (HNP) is a major cause of low back pain and sciatica. High resolution computed tomography is the most accurate diagnostic tool to define a HNP, because it provides a complete in vivo analysis of bony framework of lumbar spine as well as the supporting soft tissue structures and neural elements. But the discrepancy between neurologic findings and CT findings is often confusing. From May 1983 to August 1986, sixty patients with HNP who had both CT and surgical intervention at Pusan National University Hospital were analyzed. The feasibility of the neurologic examination on HNP and the effect of HNP on nerve root were evaluated on the basis of CT findings. The results were as follows : 1. Thirty-four cases (56.7%) of clinical impression were matched to CT findings in determining level of HNP and affected nerve root. 2. In evaluation of affected level, there was high trend to cause discrepancy between neurologic findings and CT findings in multiple disc involvement than in single involvement. 3. There was no correlation between degree of nerve root compression determined by CT and pattern of neurologic signs (motor weakness, sensory deficit, and reflex change)

  5. Analysis of discrepancy between neurologic findings and CT findings in 60 patients with herniated nucleus pulposus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun; Kim, Kab Tae; Sol, Chang Hyo; Kim, Byung Soo [College of Medicine, Pusan National University, Busan(Korea, Republic of)

    1987-06-15

    The herniated nucleus pulposus (HNP) is a major cause of low back pain and sciatica. High resolution computed tomography is the most accurate diagnostic tool to define a HNP, because it provides a complete in vivo analysis of bony framework of lumbar spine as well as the supporting soft tissue structures and neural elements. But the discrepancy between neurologic findings and CT findings is often confusing. From May 1983 to August 1986, sixty patients with HNP who had both CT and surgical intervention at Pusan National University Hospital were analyzed. The feasibility of the neurologic examination on HNP and the effect of HNP on nerve root were evaluated on the basis of CT findings. The results were as follows : 1. Thirty-four cases (56.7%) of clinical impression were matched to CT findings in determining level of HNP and affected nerve root. 2. In evaluation of affected level, there was high trend to cause discrepancy between neurologic findings and CT findings in multiple disc involvement than in single involvement. 3. There was no correlation between degree of nerve root compression determined by CT and pattern of neurologic signs (motor weakness, sensory deficit, and reflex change)

  6. Development of a new photo-detector readout technique for PET and CT imaging

    CERN Document Server

    Powolny, François; Auffray, Etiennette; Dosanjh, Manjit; Jarron, Pierre; Kaplon, Jan; Lecoq, Paul; Meyer, T C; Trummer, Julia; Velitchko, Sandra

    2007-01-01

    In the framework of the European FP6's BioCare project, we develop a novel photo-detector readout technique to increase sensitivity and timing precision for molecular imaging in Positron Emission Tomography (PET) and Computer Tomography (CT). Within the Project's work packages, the CERN-BioCare group focuses on the development of a PET detection head suitable to process data from both PET and CT operation in one unit. The detector module consists of a LSO matrix coupled to an APD array. The signal is processed by a fast and low noise readout electronics recently developed for experiments at the Large Hadron Collider (LHC) at CERN. The functioning of the individual system components and the performance of the entire readout channel are presented.

  7. Gas scintillation glass GEM detector for high-resolution X-ray imaging and CT

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, T., E-mail: fujiwara-t@aist.go.jp [Research Institute for Measurement and Analytical Instrumentation, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Mitsuya, Y. [Nuclear Professional School, The University of Tokyo, Tokai, Naka, Ibaraki 319-1188 (Japan); Fushie, T. [Radiment Lab. Inc., Setagaya, Tokyo 156-0044 (Japan); Murata, K.; Kawamura, A.; Koishikawa, A. [XIT Co., Naruse, Machida, Tokyo 194-0045 (Japan); Toyokawa, H. [Research Institute for Measurement and Analytical Instrumentation, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Takahashi, H. [Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8654 (Japan)

    2017-04-01

    A high-spatial-resolution X-ray-imaging gaseous detector has been developed with a single high-gas-gain glass gas electron multiplier (G-GEM), scintillation gas, and optical camera. High-resolution X-ray imaging of soft elements is performed with a spatial resolution of 281 µm rms and an effective area of 100×100 mm. In addition, high-resolution X-ray 3D computed tomography (CT) is successfully demonstrated with the gaseous detector. It shows high sensitivity to low-energy X-rays, which results in high-contrast radiographs of objects containing elements with low atomic numbers. In addition, the high yield of scintillation light enables fast X-ray imaging, which is an advantage for constructing CT images with low-energy X-rays.

  8. Extra-appendiceal findings in pediatric abdominal CT for suspected appendicitis

    Energy Technology Data Exchange (ETDEWEB)

    Halverson, Mark; Delgado, Jorge; Mahboubi, Soroosh [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2014-07-15

    Much has been written regarding the incidence, types, importance and management of abdominal CT incidental findings in adults, but there is a paucity of literature on incidental findings in children. We sought to determine the prevalence and characteristics of extra-appendiceal and incidental findings in pediatric abdominal CT performed for suspected appendicitis. A retrospective review was performed of abdominal CT for suspected appendicitis in a pediatric emergency department from July 2010 to June 2012. Extra-appendiceal findings were recorded. Any subsequent imaging was noted. Extra-appendiceal findings were divided into incidental findings of doubtful clinical significance, alternative diagnostic findings potentially providing a diagnosis other than appendicitis explaining the symptoms, and incidental findings that were abnormalities requiring clinical correlation and sometimes requiring further evaluation but not likely related to the patient symptoms. One hundred sixty-five children had abdominal CT for suspected appendicitis. Seventy-seven extra-appendiceal findings were found in 57 (34.5%) patients. Most findings (64 of 77) were discovered in children who did not have appendicitis. Forty-one of these findings (53%) could potentially help explain the patient's symptoms, while 30 of the findings (39%) were abnormalities that were unlikely to be related to the symptoms but required clinical correlation and sometimes further work-up. Six of the findings (8%) had doubtful or no clinical significance. Extra-appendiceal findings are common in children who undergo abdominal CT in the setting of suspected appendicitis. A significant percentage of these patients have findings that help explain their symptoms. Knowledge of the types and prevalence of these findings may help radiologists in the planning and interpretation of CT examinations in this patient population. (orig.)

  9. Noncardiac findings on cardiac CT. Part II: spectrum of imaging findings.

    LENUS (Irish Health Repository)

    Killeen, Ronan P

    2012-02-01

    Cardiac computed tomography (CT) has evolved into an effective imaging technique for the evaluation of coronary artery disease in selected patients. Two distinct advantages over other noninvasive cardiac imaging methods include its ability to directly evaluate the coronary arteries and to provide a unique opportunity to evaluate for alternative diagnoses by assessing the extracardiac structures, such as the lungs and mediastinum, particularly in patients presenting with the chief symptom of acute chest pain. Some centers reconstruct a small field of view (FOV) cropped around the heart but a full FOV (from skin to skin in the area irradiated) is obtainable in the raw data of every scan so that clinically relevant noncardiac findings are identifiable. Debate in the scientific community has centered on the necessity for this large FOV. A review of noncardiac structures provides the opportunity to make alternative diagnoses that may account for the patient\\'s presentation or to detect important but clinically silent problems such as lung cancer. Critics argue that the yield of biopsy-proven cancers is low and that the follow-up of incidental noncardiac findings is expensive, resulting in increased radiation exposure and possibly unnecessary further testing. In this 2-part review we outline the issues surrounding the concept of the noncardiac read, looking for noncardiac findings on cardiac CT. Part I focused on the pros and cons for and against the practice of identifying noncardiac findings on cardiac CT. Part II illustrates the imaging spectrum of cardiac CT appearances of benign and malignant noncardiac pathology.

  10. Comparison radiation dose of Z-axis automatic tube current modulation technique with fixed tube current multi-detector row CT scanning of lower extremity venography

    International Nuclear Information System (INIS)

    Yoo, Beong Gyu; Kweon, Dae Cheol; Lee, Jong Seok; Jang, Keun Jo; Jeon, Sang Hwan; Kim, Yong Soo

    2007-01-01

    Z-axis automatic tube current modulation technique automatically adjusts tube current based on size of body region scanned. The purpose of the current study was to compare noise, and radiation dose of Multi-Detector row CT (MDCT) of lower extremity performed with Z-axis modulation technique of automatic tube current modulation with manual selection fixed tube current. Fifty consecutive underwent MDCT venography of lower extremity with use of a MDCT scanner fixed tube current and Z-axis automatic tube current modulation technique (10, 11 and 12 HU noise index, 70∼450 mA). Scanning parameters included 120 kVp, 0.5 second gantry rotation time, 1.35:1 beam pitch, and 1 mm reconstructed section thickness. For each subject, images obtained with Z-axis modulation were compared with previous images obtained with fixed tube current (200, 250, 300 mA) and with other parameters identical. Images were compared for noise at five levels: iliac, femoral, popliteal, tibial, and peroneal vein of lower extremity. Tube current and gantry rotation time used for acquisitions at these levels were recorded. All CT examinations of study and control groups were diagnostically acceptable, though objective noise was significantly more with Z-axis automatic tube current modulation. Compared with fixed tube current, Z-axis modulation resulted in reduction of CTDIvol (range, -6.5%∼-35.6%) and DLP (range,-0.2%∼-20.2%). Compared with manually selected fixed tube current, Z-axis automatic tube current modulation resulted in reduced radiation dose at MDCT of lower extremity venography

  11. CT findings in autoimmune pancreatitis: assessment using multiphase contrast-enhanced multisection CT

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, K., E-mail: Kojiro@med.nagoya-u.ac.j [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Itoh, S. [Department of Radiology, Nagoya Hirokoji Clinic, Nagoya (Japan); Nagasaka, T. [Departments of Medical Technology, Nagoya University School of Health Science, Nagoya (Japan); Ogawa, H.; Ota, T.; Naganawa, S. [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan)

    2010-09-15

    Aim: To assess the spectrum of findings using multiphase contrast-enhanced computed tomography (CT) in patients with autoimmune pancreatitis (AIP). Materials and methods: Fifty patients (four female and 46 male, mean age 65 years) were retrospectively identified from consecutive patients with abnormal CT findings of the pancreas and negative work-up for known causes. These patients had at least one finding supporting the diagnosis of AIP: serological abnormality, histopathological abnormality, or response to steroid. Two radiologists evaluated multiphase contrast-enhanced CT images in consensus. Results: The pancreas showed diffuse enlargement (n = 16; 32%), focal enlargement (n = 18; 36%), or no enlargement (n = 16; 32%). Forty-nine (98%) patients showed abnormal contrast enhancement in the affected pancreatic parenchyma, including hypoattenuation during the pancreatic phase (n = 45; 90%) and hyperattenuation during the delayed phase (n = 39; 87%). The following findings were also seen in the pancreas: a capsule-like rim (n = 24; 48%); no visualization of the main pancreatic duct lumen (n = 48; 96%); ductal enhancement (n = 26; 52%); upstream dilatation of the main pancreatic duct (n = 27; 54%); upstream atrophy of the pancreatic parenchyma (n = 27; 54%); calcification (n = 7; 14%); and cysts (n = 5; 10%). Forty-two (84%) patients showed one or more of the following extrapancreatic findings: biliary duct or gallbladder abnormality (n = 40; 80%); peripancreatic (n = 8; 16%) or para-aortic (n = 10; 20%) soft-tissue proliferation; and renal involvement (n = 15; 30%). Conclusion: Patients with AIP presented with a variety of CT findings in the pancreas and the extrapancreatic organs. The present study highlights pancreatic ductal enhancement in a subset of patients with AIP.

  12. CT findings of superior vena cava syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jun; Lee, Jae Mun; Kim, Choon Yul; Bahk, Yong Whee [Catholic Medical College, Seoul (Korea, Republic of)

    1986-10-15

    Since early 1980's high resolution CT has been used for detection of intrathoracic pathologic condition such as superior vena cava syndrome. Authors retrospectively analysed CT findings of 18 cases of proven SVC syndrome. The results were as follows: 1. The mean age was 50-year-old, and 14 cases were male. 2. Of 18 cases of SVC syndrome, 8 cases had confirmed to be lung cancers, malignant thymoma and teratoma were respectively each 2 cases, and malignant lymphoma, mediastinal abscess, thyroid adenoma and metastatic tumor were 1 case. 3. CT findings were A. Abnormal SVC consisted of compression with displacement (44.4%), intraluminal thrombus (27.8%), and encasement (27.8%). B. The collateral pathways were the azygos-homozygous (88.8%), vertebral (50%), internal mammary (44.4%), and lateral thoracic route (33.3%)

  13. CT findings of superior vena cava syndrome

    International Nuclear Information System (INIS)

    Lim, Jun; Lee, Jae Mun; Kim, Choon Yul; Bahk, Yong Whee

    1986-01-01

    Since early 1980's high resolution CT has been used for detection of intrathoracic pathologic condition such as superior vena cava syndrome. Authors retrospectively analysed CT findings of 18 cases of proven SVC syndrome. The results were as follows: 1. The mean age was 50-year-old, and 14 cases were male. 2. Of 18 cases of SVC syndrome, 8 cases had confirmed to be lung cancers, malignant thymoma and teratoma were respectively each 2 cases, and malignant lymphoma, mediastinal abscess, thyroid adenoma and metastatic tumor were 1 case. 3. CT findings were A. Abnormal SVC consisted of compression with displacement (44.4%), intraluminal thrombus (27.8%), and encasement (27.8%). B. The collateral pathways were the azygos-homozygous (88.8%), vertebral (50%), internal mammary (44.4%), and lateral thoracic route (33.3%).

  14. CT findings of cerebral paragonimiasis in the chronic state

    International Nuclear Information System (INIS)

    Udaka, F.; Okuda, B.; Tsuji, T.; Kameyama, M.; Okada, M.

    1988-01-01

    The CT findings in 5 patients with cerebral paragonimiasis in the chronic state are presented. The findings were: 1) multiple, densely calcified areas with a variety of round or nodular shapes in the brain, 2) a large low density area surrounding or connecting with the calcified areas, and 3) cortical atrophy and ventricular dilatation. The relation between the CT findings and the previously reported plain skull X-ray findings or neuropathological findings are discussed. (orig.)

  15. CT findings in the leptomeningeal dissemination of tumors

    International Nuclear Information System (INIS)

    Yamazaki, Shingo; Ito, Umeo; Tomita, Hiroki; Takada, Yoshiaki; Ohno, Kikuo; Momma, Seiji; Inaba, Yutaka.

    1986-01-01

    The communicating hydrocephalus, the enhancement of the basal and quadrigeminal cisterns, and the enhancement of the Sylvian fissure, the cortical sulci and the ventricular wall are CT findings reported with regard to the leptomeningeal dissemination of tumors (LMDT). However, these findings are not always observed in patients with LMDT. In the present study, CT findings on 4 patients with LMDT (one from spinal ependymoblastoma, two from gastric cancer; and one from pulmonary cancer) are reported. Depending on the stage of the disease, the appearances of the above LMDT are quite varied. In Case 1, only hydrocephalus was found on admission CT. About one month later, the enhancement of the basal cisterns, the Sylvian fissure, the cerebral sulci, and the ventricular wall was observed, and this enhancement was further intensified later on. In Case 2, the cortical sulci were enhanced without any enhancement of the hydrocephalus or anything else. In Case 3, only the cerebral margin of the posterior lobectomy was enhanced. In Case 4, only a communicating hydrocephalus was observed. However, in all four cases the CSF cytology was positive for tumor cells. The frequency of each CT finding is discussed for the reported 25 cases. (author)

  16. CT findings of osteogenesis imperfecta

    Energy Technology Data Exchange (ETDEWEB)

    Kojo, Nobuto; Otsuru, Katsuyasu; Lee, Soichi; Takagi, Shigeyuki; Shigemori, Minoru.

    1987-08-01

    Two cases of osteogenesis imperfecta found in one family (father and daughter) are reported, and the CT findings are described. Case 1 is a 58-year-old man who fell and struck his head at home on November 10, 1984. He was transferred to Omuta City Hospital when he became semicomatose and decerebrate posturing was noted. His family history revealed 8 persons with osteogenesis imperfecta. A skull X-ray film showed a large skull vault, many wormian bones at the lambdoid suture, platybasia, and a basilar impression. A CT scan demonstrated a right acute subdural hematoma, while the bone image showed well-developed mastoid air cells and a skull deformity characteristic of osteogenesis imperfecta. He had an emergency operation, and a 170-gr clot was successfully evacuated. A postoperative CT scan demonstrated brain atrophy, possibly present before head trauma. Case 2 is the daughter of Case 1 (a 27-year-old woman). She also showed characteristic neuroradiological manifestations on a plain skull film and on a CT scan. A basilar impression and platybasia were also demonstrated. In this report, the possible mechanism of the production of a traumatic acute subdural hematoma is also discussed.

  17. CT findings of osteogenesis imperfecta

    International Nuclear Information System (INIS)

    Kojo, Nobuto; Otsuru, Katsuyasu; Lee, Soichi; Takagi, Shigeyuki; Shigemori, Minoru.

    1987-01-01

    Two cases of osteogenesis imperfecta found in one family (father and daughter) are reported, and the CT findings are described. Case 1 is a 58-year-old man who fell and struck his head at home on November 10, 1984. He was transferred to Omuta City Hospital when he became semicomatose and decerebrate posturing was noted. His family history revealed 8 persons with osteogenesis imperfecta. A skull X-ray film showed a large skull vault, many wormian bones at the lambdoid suture, platybasia, and a basilar impression. A CT scan demonstrated a right acute subdural hematoma, while the bone image showed well-developed mastoid air cells and a skull deformity characteristic of osteogenesis imperfecta. He had an emergency operation, and a 170-gr clot was successfully evacuated. A postoperative CT scan demonstrated brain atrophy, possibly present before head trauma. Case 2 is the daughter of Case 1 (a 27-year-old woman). She also showed characteristic neuroradiological manifestations on a plain skull film and on a CT scan. A basilar impression and platybasia were also demonstrated. In this report, the possible mechanism of the production of a traumatic acute subdural hematoma is also discussed. (author)

  18. CT findings in children with Meckel diverticulum

    International Nuclear Information System (INIS)

    Olson, Doug E.; Donnelly, Lane F.; Kim, Yong-Woo

    2009-01-01

    Approximately 0.04% of the general population will present with a complication related to Meckel diverticulum. The classic teaching is that symptomatic children with Meckel diverticulum present with painless rectal bleeding and are evaluated with a radionuclide scan. Our subjective experience is that we see children with Meckel diverticulum who present with abdominal pain and are evaluated by CT. We reviewed the findings on CT in children with pathologically proven Meckel diverticulum to identify characteristic patterns of presentation. Databases were searched (2004-2008) for all children who had a pathologic diagnosis of Meckel diverticulum and a CT scan performed prior to surgery. Demographics, pathology, and CT features were reviewed. CT features reviewed included: soft-tissue stranding, abnormal calcifications, bowel obstruction, free air, free peritoneal fluid, cystic mass, intussusception, obvious lead point, location, and whether a normal appendix was identified. The frequency of Meckel diverticulum encountered on CT scans was compared to that found during the same period of time on technetium pertechnetate studies. The review identified 16 subjects (mean age 9.5 years, M:F 9:7). CT findings included: soft-tissue stranding in nine (56%), small-bowel obstruction (SBO) in nine (56%), intussusception in three (19%), free fluid in ten (63%), cystic mass in four (25%), calcification in none (0%), free air in one (6%), and no abnormalities in two (13%). A normal appendix was identified in only five children (31%). There were three basic patterns of presentation of abnormalities: SBO only in five, intussusception with SBO in three, or cystic mass with inflammatory stranding in four (one with SBO). Also, 2.3 times more Meckel diverticulum was encountered on CT than on technetium pertechnetate studies. Meckel diverticulum is currently more commonly encountered in children on CT performed for abdominal pain than on technetium pertechnetate studies. There are three

  19. Ring artifact correction for high-resolution micro CT

    International Nuclear Information System (INIS)

    Kyriakou, Yiannis; Prell, Daniel; Kalender, Willi A

    2009-01-01

    In high-resolution micro CT using flat detectors (FD), imperfect or defect detector elements may cause concentric-ring artifacts due to their continuous over- or underestimation of attenuation values, which often disturb image quality. We here present a dedicated image-based ring artifact correction method for high-resolution micro CT, based on median filtering of the reconstructed image and working on a transformed version of the reconstructed images in polar coordinates. This post-processing method reduced ring artifacts in the reconstructed images and improved image quality for phantom and in in vivo scans. Noise and artifacts were reduced both in transversal and in multi-planar reformations along the longitudinal axis. (note)

  20. Chronic eosinophilic pneumonia: CT findings

    International Nuclear Information System (INIS)

    Gutierrez, Haydee; Beccar Varela, Lucia; De Felippi, Maria S.

    2002-01-01

    Objective: To assess the usefulness of computerized tomography (CT) in the diagnosis of chronic eosinophilic pneumonia. Material and Methods: A double helical CT was performed in 6 patients referred to our center because of a chest X-ray with pulmonary infiltrates. Clinical presentation was cough, fever and eosinophilia in peripheral blood. Patients' age ranged from 25 to 55 years; 4 were women and 2 were men, one of the latter had a history of bronchial asthma. All patients received treatment with corticosteroids, with remission of the clinical and radiological parameters. Three patients underwent a control CT. Results: Findings consisted in focal parenchymal alterations, with areas of pulmonary consolidation and areas of 'ground glass' appearance; both patterns coexisted in certain areas. In 3 cases the lesions extended from the apices to the pulmonary bases, with predominance of the upper and middle fields. In 1 patient, there was frank predominance in the left hemi thorax. In another patient, who had a history of asthma, there were signs of pulmonary hyperinflation, with diffuse thickening of the bronchial walls, added to the previously mentioned findings, which involved the entire lung. In the mediastinum, 1 patient had lymph nodes larger than 1 cm, 3 had lymph nodes that were not enlarged but were more numerous than usual, and in the remaining patients no lymph nodes were found. The control CT's showed almost total resolution of the pulmonary infiltrates. Conclusion: The combination of eosinophilia and characteristic pulmonary infiltrates with a likely clinical presentation, associated with an optimal response to treatment with corticosteroids allows to make a reliable diagnosis and avoids the need for a pulmonary biopsy. (author)

  1. Comparison of image quality in head CT studies with different dose-reduction strategies

    DEFF Research Database (Denmark)

    Johansen, Jeppe; Nielsen, Rikke; Fink-Jensen, Vibeke

    The number of multi-detector CT examinations is increasing rapidly. They allow high quality reformatted images providing accurate and precise diagnosis at maximum speed. Brain examinations are the most commonly requested studies, and although they come at a lower effective dose than body CT, can...... account to a considerable radiation dose as many patients undergo repeated studies. Therefore, various dose-reduction strategies are applied such as automated tube current and voltage modulation and recently different iterative reconstruction algorithms. However, the trade-off of all dose......-reduction maneuvers is reduction of image quality due to image noise or artifacts. The aim of our study was therefore to find the best diagnostic images with lowest possible dose. We present results of dose- and image quality optimizing strategies of brain CT examinations at our institution. We compare sequential...

  2. Primary epiploic appendagitis: US and CT findings

    International Nuclear Information System (INIS)

    Molla, E.; Ripolles, T.; Martinez, M.J.; Morote, V.; Rosello-Sastre, E.

    1998-01-01

    A retrospective review is presented of seven cases of epiploic appendagitis, with surgical confirmation in one case. The main clinico-analytical data and the US and CT findings are described, as well as the histopathologic features in the sole case that underwent surgical resection. We also calculated the frequency of this entity in patients undergoing emergency abdominal US on clinical suspicion of diverticulitis. In all seven cases the clinico-analytical evidence was nonspecific (localized acute abdominal pain and slight leukocytosis), mimicking in six cases the clinical presentation of sigmoid diverticulitis and in one case that of acute appendicitis. US imaging findings were characteristic: a hyperechoic mass localized under the point of maximum pain, adjacent to the anterior peritoneal wall and fixed during deep breathing. In none of the cases did color Doppler US show flow. CT findings were also typical and showed a mass with a peripheral hyperattenuated rim surrounding an area of fatty attenuation. Overall 7.1 % of patients investigated to exclude sigmoid diverticulitis finally showed findings of primary epiploic appendagitis. Primary epiploic appendagitis thus shows characteristic US and CT findings that allow its diagnosis and follow-up. This entity is much more frequent than previously reported, especially in patients referred for US to exclude sigmoid diverticulitis. (orig.)

  3. Necrotizing pneumonia: CT findings and its clinical significance

    International Nuclear Information System (INIS)

    Park, Hong Suk; Im, Jung Gi; Ryoo, Jae Wook; Yeon, Kyung Mo; Han, Man Chung

    1995-01-01

    To analyze CT and follow-up chest radiographic findings in patients with necrotizing pneumonia and to evaluate clinical significance of the extent of necrosis. We reviewed medical records and retrospectively analysed CT scans and follow-up chest radiographs of 22 patients with necrotizing pneumonia, confirmed by biopsy (n = 7) and culture (n = 15). Inclusion criteria for necrotizing pneumonia was necrotic low attenuation, with or without cavitation on postcontrast enhanced CT scan. The study group included 15 men and seven women, aged 11-66 years (average: 47 years). The pathogens of necrotizing pneumonia were Klebsiella spp (n = 7), Enterobacter spp (n = 5), Actinomyces spp (n = 4), Pseudomonas spp (n = 4), Nocardia spp (n = 4), and others (n = 5). Average duration of pneumonia was 4.1 months. On CT scan, pneumonic consolidations were well-marginated in 14 patients and there were cavities on initial CT scan in 16 cases. Margins of the necrotic portion on CT scan were well-demarcated in majority of the patients (16/22). Low attenuation areas on initial CT scan resulted in cavitation, fibrosis and volume loss as shown on follow-up chest radiographs. The larger the necrotic areas on CT, the more the volume loss was. CT findings of necrotizing pneumonia were well-marginated air-space consolidation with low attenuation area, with or without cavity. The extent of necrotic area was closely related with the degree of fibrotic change later on. CT is important tool for diagnosis and prediction of parenchymal damage in necrotizing pneumonia

  4. CT findings in skeletal cystic echinococcosis

    Energy Technology Data Exchange (ETDEWEB)

    Tuezuen, M.; Hekimoglu, B. [Social Security Hospital, Ankara (Turkey). Dept. of Radiology

    2002-09-01

    Purpose: To evaluate the CT findings of skeletal cystic echinococcosis. Material and Methods: CT findings of 7 patients with pathologically confirmed skeletal cystic echinococcosis were evaluated. Results: There were 4 men and 3 women, aged 36-75 years. Hydatid cysts were located in the spine (n=2), a rib (n=3), the pelvis and a vertebra (n=1), the pelvis and the left femur (n=1). The size of the lesions varied from 1 cm to 15 cm. CT showed well defined, single or multiple cystic lesions with no contrast enhancement, no calcification, no daughter cysts, and no germinal membrane detachment. The cystic lesion had a honeycomb appearance in 2 cases, there was pathologic fracture in 2 cases, bone expansion in 5 cases, cortical thinning in 6 cases, cortical destruction in 6 cases, bone sclerosis in 1 case, and soft tissue extension in 6 cases. Conclusion: Preoperative differential diagnosis of skeletal cystic lesions should include cystic echinococcosis, especially in endemic areas, since this diagnosis may easily be missed unless kept in mind.

  5. Chest CT findings in pediatric Wegener's granulomatosis

    International Nuclear Information System (INIS)

    Levine, Daniel; Akikusa, Jonathan; Manson, David; Silverman, Earl; Schneider, Rayfel

    2007-01-01

    Although pulmonary involvement occurs in the majority of children and adolescents with Wegener's granulomatosis (WG), relatively little has been published regarding the CT imaging manifestations in this group of patients. To determine the frequency and types of chest CT abnormalities in active pediatric WG (pWG). The study was a retrospective examination of 29 chest CT examinations performed at diagnosis (n=14) and during disease flares (n=15) in 18 children. The most common abnormalities were nodules (seen in 90% of examinations), ground-glass opacification (52%), and air-space opacification (45%). Of examinations with nodules, 73% demonstrated nodules >5 mm in diameter and 69% demonstrated more than five nodules; 17% had cavitary lesions. The only abnormality with a significant difference in prevalence between diagnosis and disease flares was air-space opacification, present in 71% and 20%, respectively (P < 0.01). In accordance with the findings of published adult studies and at variance with those of prior pediatric studies, our findings indicate that chest CT abnormalities in active pWG are frequent, most commonly comprising nodules and ground-glass opacification, which may be difficult to detect on plain radiography. We therefore advocate the routine use of chest CT for all affected patients, both at the time of presentation and during disease flares. (orig.)

  6. Clinically relevant incidental cardiovascular findings in CT examinations

    International Nuclear Information System (INIS)

    Voigt, P.; Fahnert, J.; Kahn, T.; Surov, A.; Schramm, D.; Bach, A.G.

    2017-01-01

    Incidental cardiovascular findings are a frequent phenomenon in computed tomography (CT) examinations. As the result of a dedicated PubMed search this article gives a systemic overview of the current literature on the most important incidental cardiovascular findings, their prevalence and clinical relevance. The majority of incidental cardiovascular findings are of only low clinical relevance; however, highly relevant incidental findings, such as aortic aneurysms, thromboses and thromboembolic events can also occasionally be found, especially in oncology patients. The scans from every CT examination should also be investigated for incidental findings as they can be of decisive importance for the further clinical management of patients, depending on their clinical relevance. (orig.) [de

  7. CT findings of peritoneal mesothelioma

    International Nuclear Information System (INIS)

    Woo, Young Hoon; Oh, Yeon Hee; Kim, Hong; Kim, Jung Sik; Woo, Seong Ku; Kim, Ok Bae; Joo, Yang Goo

    1990-01-01

    The peritoneal mesothelioma is a rare neoplasm which arises from the peritoneal lining of the abdomen, tending to spread along the peritoneal cavity and to invade abdominal organs. Authors report the CT findings of 4 patients with histologically proven peritoneal mesothelioma seen at Dongsan Medical Center, School of Medicine, Keimyung University. None of them had a history of exposure to asbestos and no clear etiologic factor could be determined in any patient. CT showed peritoneal and mesenteric thickenings in all cases, omental thickenings in 3 cases, peritoneal nodules, mesenteric masses or omental masses in 2 cases each other, bowel wall involvement in 1 case, and disproportionally small ascites in 2 cases. Distant hematogenous metastases to the liver and retroperitoneal lymph nodes were seen in 1 case. Our experience with 4 peritoneal mesotheliomas as well as a review of the recent imaging literature shows excellent correlation between computed tomography and the operitoneoscopic findings

  8. Membranous lipodystrophy: skeletal findings on CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Nwawka, O.K.; Schneider, Robert; Mintz, Douglas N. [Hospital for Special Surgery, Department of Radiology and Imaging, New York, NY (United States); Bansal, Manjula [Hospital for Special Surgery, Department of Pathology and Laboratory Medicine, New York, NY (United States); Lane, Joseph [Hospital for Special Surgery, Department of Orthopedic Surgery, New York, NY (United States)

    2014-10-15

    Membranous lipodystrophy, also known as Nasu-Hakola disease, is a rare hereditary condition with manifestations in the nervous and skeletal systems. The radiographic appearance of skeletal lesions has been well described in the literature. However, CT and MRI findings of lesions in the bone have not been documented to date. This report describes the radiographic, CT, MRI, and histopathologic skeletal findings in a case of membranous lipodystrophy. With corroborative pathologic findings, a diagnosis of membranous lipodystrophy on imaging allows for appropriate clinical management of disease manifestations. (orig.)

  9. CT findings of lymphofollicular thymic hyperplasia in adult myasthenia gravis

    International Nuclear Information System (INIS)

    Liu Fugeng; Wei Jiahu; Pan Jishu; Zhou Cheng; Chen Qihang; Yu Jingying; Wu Guogeng; Xu Xianhao

    2006-01-01

    Objective: To evaluate the CT findings of lymphofollicular thymic hyperplasia in adult myasthenia gravis (MG). Methods: The CT findings of thymus area of 134 adult patients with lymphofollicular thymic hyperplasia in MG were reviewed, all of them with surgically and histologically proven diagnosis, and compared with the CT findings of 165 normal subjects. Results: In the group of patient, CT showed enlargement of thymus in 31 patients, 5 patients had nodule or mass ( 3 cm) and 9 patients (6.7%) had normal size thymus with soft-tissue density, it can considered with thymic hyperplasia. The spotty or streak shadow showed in other patients, though it could not be certain diagnosed as thymic hyperplasia, but could not be except it. The thymus area tissue complete replacement by fatty density were not found in patient group. The CT findings of patients had marked difference when compared with group of normal subjects (P<0.01), except the spotty or streak shadows. Conclusion: CT scan is an important method in diagnosing thymic lymphofollicular hyperplasia of MG in adult. (authors)

  10. CT findings of cerebral palsy and behaviour development

    International Nuclear Information System (INIS)

    Sakamoto, Zenji

    1987-01-01

    It is well recognized that CT scan is very useful in the early diagnosis of cerebral palsy. The author has studied this time the CT scan findings of cerebral palsy children in their relations to the type of palsy, cause of palsy, complications in the central nervous system, and prognosis of behaviour development, in order to predict the prognosis of behaviour development. Dilatation of the contralateral cerebral ventricle was found in 82 % of hemiplegic type. Abnormal EEG was found in 73 %, but their behaviour development was satisfactory, with good development of speech regardless to the side of palsy. This might be helped by compensational function of the brain due to plasticity. Diplegia presented bilateral moderate dilatation of ventricles with favorable prognosis. Tetraplegia was caused mostly by asphyxia or congenital anomaly and revealed marked dilatation of ventricles or severe cortical atrophy. Some cases presented diffuse cortical low-density, often associated with abnormal EEG, and their prognosis was worst. Athetosis had normal CT finding or mild ventricular dilatation, but all cases of ataxia presented normal CT findings. Hypotonia had mild ventricular dilatation. Two of three mixed type cases had normal CT findings and another had mild ventricular dilatation. No correlation was found between ventricular dilatation and behaviour development, but statistically significant difference was found in the cases with 30 % or more Evans' ratio (P < 0.05). Prognosis of severe ventricular dilatation cases was poor. (author)

  11. Primary thyroid lymphoma: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo-Cheol; Han, Moon Hee E-mail: hanmh@radcom.snu.ac.kr; Kim, Keon Ha; Jae, Hwan Jun; Lee, Sang Hyun; Kim, Sam Soo; Kim, Kwang Hyun; Chang, Kee-Hyun

    2003-06-01

    Introduction: To evaluate the computed tomographic (CT) findings of primary thyroid lymphoma. Methods and material: The clinicopathological data and CT images of nine patients with primary thyroid lymphoma were retrospectively reviewed. The CT appearances were classified into three types: type 1, a solitary nodule surrounded by normal thyroid tissue; type 2, multiple nodules in the thyroid, and type 3, a homogeneously enlarged both thyroid glands with a reduced attenuation with or without peripheral thin hyperattenuating thyroid tissue. Results: All patients had a rapidly enlarging thyroid mass and coexistent Hashimoto's thyroiditis. One patient showed type 1 pattern, three type 2, and five type 3. Six patients had homogeneous tumor isoattenuating to surrounding muscles. The tumors had a strong tendency to compress normal remnant thyroid and the surrounding structure without invasion. Conclusion: Primary thyroid lymphoma should be included in the differential diagnosis when old female had a homogeneous thyroidal mass isoattenuating to muscles, which does not invade surrounding structures.

  12. Positron CT findings of chronic schizophrenics

    International Nuclear Information System (INIS)

    Toyoda, Junzo; Miyazaki, Chihiro; Sugai, Yuichi; Iio, Masaaki.

    1983-01-01

    Positron CT images of 15 chronic schizophrenics (2 females and 13 males) were examined in contrast to 5 male controls. Average age of controls was 36 years and that of schizophrenics was 42 years. Schizophrenic cases were ill over 6 years, averaging 17 years. All were under antipsychotic drug therapy. Tracer compounds were 11 C-CO2 and 11 C-glucose photosynthesised, the former being inhalated once just before and the latter being administered orally 10-15 minutes before examinations. On positron CT images of all normal controls, hyper-radioactivities in frontal regions were observed. Some asymmetries of activities were observed but not remarkable. There wes no difference between the images with 11 C-CO2 and those with 11 C-glucose. In schizophrenic cases, (1) 7 out of 15 cases showed hypo-activities in the frontal regions both with 11 C-CO2 and 11 C-glucose. (2) With 11 C-glucose, relative activities in the brain were lower than those in the soft tissues around the scalp, suggesting the lowered selective uptake of 11 C-glucose by the brain. (3) With 11 C-CO 2, 4 cases showed higher activities in the right temporal regions and their subcortex than the left. By consideration of relationships between these positron CT findings and clinical data such as present age, age of onset of illness, duration of illness, psychiatric symptoms, present drug amount, summed drug amount from administration, EEG and X-ray CT findings, significant correlation was recognized only between low frontal radioactivities and apathy-abulia as main symptom. Limitation on the explanation of the findings with the image alone was discussed. (author)

  13. Multidetector CT findings of bowel Transection in blunt abdominal trauma

    International Nuclear Information System (INIS)

    Cho, Hyun Suk; Woo, Ji Young; Hong, Hye Suk; Park, Mee Hyun; Yang, Ik; Lee, Yul; Jung, Ah Young; Hwang, Ji Young; Ha, Hong Il

    2013-01-01

    Though a number of CT findings of bowel and mesenteric injuries in blunt abdominal trauma are described in literature, no studies on the specific CT signs of a transected bowel have been published. In the present study we describe the incidence and new CT signs of bowel transection in blunt abdominal trauma. We investigated the incidence of bowel transection in 513 patients admitted for blunt abdominal trauma who underwent multidetector CT (MDCT). The MDCT findings of 8 patients with a surgically proven complete bowel transection were assessed retrospectively. We report novel CT signs that are unique for transection, such as complete cutoff sign (transection of bowel loop), Janus sign (abnormal dual bowel wall enhancement, both increased and decreased), and fecal spillage. The incidence of bowel transection in blunt abdominal trauma was 1.56%. In eight cases of bowel transection, percentage of CT signs unique for bowel transection were as follows: complete cutoff in 8 (100%), Janus sign in 6 (100%, excluding duodenal injury), and fecal spillage in 2 (25%). The combination of complete cutoff and Janus sign were highly specific findings in patients with bowel transection. Complete cut off and Janus sign are the unique CT findings to help detect bowel transection in blunt abdominal trauma and recognition of these findings enables an accurate and prompt diagnosis for emergency laparotomy leading to reduced mortality and morbidity.

  14. CT, MRI, and FDG-PET/CT imaging findings of abdominopelvic desmoplastic small round cell tumors: Correlation with histopathologic findings

    International Nuclear Information System (INIS)

    Zhang Weidong; Li Chuanxing; Liu Qingyu; Hu Yingying; Cao Yun; Huang Jinhua

    2011-01-01

    Objective: To analyze computed tomography (CT), magnetic resonance imaging (MRI), and fluorodeoxyglucose-positron emission tomography (FDG-PET)/CT imaging features of abdominopelvic desmoplastic small round cell tumor (DSRCT) and to improve the diagnostic efficacy of these techniques for the detection of such tumor. Methods: We retrospectively analyzed 7 cases of abdominopelvic DSRCT confirmed by histopathologic analysis. Among the 7 patients, 5 patients had undergone CT scanning, 2 of which were also examined with FDG-PET/CT imaging, and 2 had undergone MRI. Unenhanced and contrast-enhanced examinations were performed in all patients, and 2 patients had also undergone dynamic CT contrast-enhanced examinations. Image characteristics, such as shape, size, number, edge, attenuation, and intensity of each lesion before and after contrast enhancement were analyzed and compared with the pathomorphology of the tumors. Results: Multiple large masses in the abdominopelvis were detected in 6 cases, and a large mass in the pelvis was detected in 1 case. Six cases showed largest mass in pelvis, and 1 case in mesentery. None of the masses had a definite organ origin. CT showed soft tissue masses with patchy foci of hypodense areas. MR T1-weighted images revealed lesions with mild hypointense areas and patchy hypointense areas in 2 cases and lesions with patchy hyperintense areas in 1 case. T2-weighted images showed lesions with mixed isointense and hyperintense areas in 1 case and lesions with mixed hypointense, isointense, and hyperintense areas in another. Contrast-enhanced CT and T1-weighted images showed mildly heterogeneous enhancement of the lesions. Other associated findings included peritoneal seeding (n = 3), peritoneal effusions (n = 3), hepatic metastasis (n = 2), bone metastasis (n = 1), and mesenteric and retroperitoneal lymphadenopathy (n = 4). FDG-PET/CT showed multiple nodular foci of increased metabolic activity in the abdominopelvic masses, in the hepatic and

  15. CT and MRI findings of calcified spinal meningiomas: correlation with pathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Won; Kim, Hak Jin [Pusan National University Hospital, Department of Radiology, Busan (Korea); Pusan National University School of Medicine, Medical Research Institute, Busan (Korea); Lee, In Sook [Pusan National University Hospital, Department of Radiology, Busan (Korea); Pusan National University School of Medicine, Medical Research Institute, Busan (Korea); Pusan National University School of Medicine, Department of Radiology, Busan (Korea); Choi, Kyung-Un [Pusan National University School of Medicine, Medical Research Institute, Busan (Korea); Pusan National University Hospital, Department of Pathology, Busan (Korea); Lee, Young Hwan [Catholic University of Daegu School of Medicine, Department of Radiology, Daegu (Korea); Yi, Jae Hyuck [Kyungpook National University Hospital, Department of Radiology, Daegu (Korea); Song, Jong Woon [Inje University Pusan Paik Hospital, Department of Radiology, Busan (Korea); Suh, Kyung Jin [Dongguk University Gyungju Hospital, College of Medicine, Dongguk University, Department of Radiology, Gyungju (Korea)

    2010-04-15

    This study was designed to present characteristic CT and MR findings of calcified spinal meningiomas that correlate with pathological findings and to assess the efficacy of CT for the detection of calcifications within a mass in comparison to MRI. Between 1998 and 2009, 10 out of 11 patients who had pathologically confirmed psammomatous meningiomas showed gross calcifications on CT images and were included in this study. On CT scans of the 10 patients, the distribution pattern, morphology and number of calcifications within masses were evaluated. MRI was performed in seven patients and signal intensities of masses were assessed. The pathological results analyzed semi-quantitatively were compared with the density or the size of calcifications within a mass as seen on a CT scan. Seven of 10 masses were located at the thoracic spine level. Eight masses had intradural locations. The other two masses had extradural locations. Four masses were completely calcified based on standard radiographs and CT. Symptoms duration, the size of the mass and size or number of calcifications within a mass had no correlation. The location, size, and distribution pattern of calcifications within masses were variable. On MR images, signal intensity of calcified tumor varied on all imaging sequences. All the masses enhanced after injection of intravenous contrast material. A calcified meningioma should be first suggested when extradural or intradural masses located in the spine contain calcifications regardless of the size or pattern as depicted on CT, especially in the presence of enhancement as seen on MR images. (orig.)

  16. WE-B-207-00: CT Lung Cancer Screening Part 1

    International Nuclear Information System (INIS)

    2015-01-01

    The US National Lung Screening Trial (NLST) was a multi-center randomized, controlled trial comparing a low-dose CT (LDCT) to posterior-anterior (PA) chest x-ray (CXR) in screening older, current and former heavy smokers for early detection of lung cancer. Recruitment was launched in September 2002 and ended in April 2004 when 53,454 participants had been randomized at 33 screening sites in equal proportions. Funded by the National Cancer Institute this trial demonstrated that LDCT screening reduced lung cancer mortality. The US Preventive Services Task Force (USPSTF) cited NLST findings and conclusions in its deliberations and analysis of lung cancer screening. Under the 2010 Patient Protection and Affordable Care Act, the USPSTF favorable recommendation regarding lung cancer CT screening assisted in obtaining third-party payers coverage for screening. The objective of this session is to provide an introduction to the NLST and the trial findings, in addition to a comprehensive review of the dosimetry investigations and assessments completed using individual NLST participant CT and CXR examinations. Session presentations will review and discuss the findings of two independent assessments, a CXR assessment and the findings of a CT investigation calculating individual organ dosimetry values. The CXR assessment reviewed a total of 73,733 chest x-ray exams that were performed on 92 chest imaging systems of which 66,157 participant examinations were used. The CT organ dosimetry investigation collected scan parameters from 23,773 CT examinations; a subset of the 75,133 CT examinations performed using 97 multi-detector CT scanners. Organ dose conversion coefficients were calculated using a Monte Carlo code. An experimentally-validated CT scanner simulation was coupled with 193 adult hybrid computational phantoms representing the height and weight of the current U.S. population. The dose to selected organs was calculated using the organ dose library and the abstracted scan

  17. WE-B-207-00: CT Lung Cancer Screening Part 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    The US National Lung Screening Trial (NLST) was a multi-center randomized, controlled trial comparing a low-dose CT (LDCT) to posterior-anterior (PA) chest x-ray (CXR) in screening older, current and former heavy smokers for early detection of lung cancer. Recruitment was launched in September 2002 and ended in April 2004 when 53,454 participants had been randomized at 33 screening sites in equal proportions. Funded by the National Cancer Institute this trial demonstrated that LDCT screening reduced lung cancer mortality. The US Preventive Services Task Force (USPSTF) cited NLST findings and conclusions in its deliberations and analysis of lung cancer screening. Under the 2010 Patient Protection and Affordable Care Act, the USPSTF favorable recommendation regarding lung cancer CT screening assisted in obtaining third-party payers coverage for screening. The objective of this session is to provide an introduction to the NLST and the trial findings, in addition to a comprehensive review of the dosimetry investigations and assessments completed using individual NLST participant CT and CXR examinations. Session presentations will review and discuss the findings of two independent assessments, a CXR assessment and the findings of a CT investigation calculating individual organ dosimetry values. The CXR assessment reviewed a total of 73,733 chest x-ray exams that were performed on 92 chest imaging systems of which 66,157 participant examinations were used. The CT organ dosimetry investigation collected scan parameters from 23,773 CT examinations; a subset of the 75,133 CT examinations performed using 97 multi-detector CT scanners. Organ dose conversion coefficients were calculated using a Monte Carlo code. An experimentally-validated CT scanner simulation was coupled with 193 adult hybrid computational phantoms representing the height and weight of the current U.S. population. The dose to selected organs was calculated using the organ dose library and the abstracted scan

  18. Haemodynamic findings on cardiac CT in children with congenital heart disease

    International Nuclear Information System (INIS)

    Goo, Hyun Woo

    2011-01-01

    In patients with congenital heart disease, haemodynamic findings demonstrated on cardiac CT might provide useful hints for understanding the haemodynamics of cardiac defects. In contrast to morphological features depicted on cardiac CT, such haemodynamic findings on cardiac CT have not been comprehensively reviewed in patients with congenital heart disease. This article describes normal haemodynamic phenomena of cardiovascular structures and various abnormal haemodynamic findings with their mechanisms and clinical significance on cardiac CT in patients with congenital heart disease. (orig.)

  19. Identifying the most infectious lesions in pulmonary tuberculosis by high-resolution multi-detector computed tomography

    International Nuclear Information System (INIS)

    Yeh, Jun Jun; Chen, Solomon Chih-Cheng; Teng, Wen-Bao; Chou, Chun-Hsiung; Hsieh, Shih-Peng; Lee, Tsung-Lung; Wu, Ming-Ting

    2010-01-01

    This study aimed to determine whether characteristics detected by multi-detector computed tomography (MDCT) were predictive of highly infectious, smear-positive, active pulmonary tuberculosis (PTB). Among 124 patients with active PTB, 84 had positive (group 1) and 40 had negative (group 2) smear results for acid-fast bacilli. Multiplanar MDCT, axial conventional CT and chest X-ray images were analysed retrospectively for morphology, number, and segmental (lobe) distribution of lesions. By multivariate analysis, consolidation over any segment of the upper, middle, or lingual lobes, cavitations, and clusters of nodules were associated with group 1, while centrilobular nodules were predictive of group 2. Using five independent variables associated with risk in group 1, a prediction model was created to distinguish between group 1 and group 2. ROC curve analysis showed an area under the curve of 0.951 ± 0.021 for this prediction model. With the ideal cutoff point score of 1, the sensitivity, specificity, and positive predictive values were 84.5%, 97.5%, and 98.0%, respectively. A model to predict smear-positive active PTB on the basis of findings from MDCT may be a useful tool for clinical decisions about isolating patients pending sputum smear results. (orig.)

  20. Identifying the most infectious lesions in pulmonary tuberculosis by high-resolution multi-detector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Jun Jun [Pingtung Christian Hospital, Pingtung (China); Mei-Ho Institute of Technology, Pingtung (China); China Medical University, Taichung (China); Chen, Solomon Chih-Cheng [Pingtung Christian Hospital, Pingtung (China); National Taiwan University, Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, Taipei (China); Teng, Wen-Bao; Chou, Chun-Hsiung; Hsieh, Shih-Peng; Lee, Tsung-Lung [Pingtung Christian Hospital, Pingtung (China); Wu, Ming-Ting [National Yang Ming University, Faculty of Medicine, School of Medicine, Taipei (China); Kaohsiung Veterans General Hospital, Section of Thoracic and Circulation Imaging, Department of Radiology, Kaohsiung (China)

    2010-09-15

    This study aimed to determine whether characteristics detected by multi-detector computed tomography (MDCT) were predictive of highly infectious, smear-positive, active pulmonary tuberculosis (PTB). Among 124 patients with active PTB, 84 had positive (group 1) and 40 had negative (group 2) smear results for acid-fast bacilli. Multiplanar MDCT, axial conventional CT and chest X-ray images were analysed retrospectively for morphology, number, and segmental (lobe) distribution of lesions. By multivariate analysis, consolidation over any segment of the upper, middle, or lingual lobes, cavitations, and clusters of nodules were associated with group 1, while centrilobular nodules were predictive of group 2. Using five independent variables associated with risk in group 1, a prediction model was created to distinguish between group 1 and group 2. ROC curve analysis showed an area under the curve of 0.951 {+-} 0.021 for this prediction model. With the ideal cutoff point score of 1, the sensitivity, specificity, and positive predictive values were 84.5%, 97.5%, and 98.0%, respectively. A model to predict smear-positive active PTB on the basis of findings from MDCT may be a useful tool for clinical decisions about isolating patients pending sputum smear results. (orig.)

  1. Ultrasonographic and CT findings of hepatosplenic tuberculosis

    International Nuclear Information System (INIS)

    Moon, Un Hyeon; Lee, Jeong Seok; Ko, Kang Seok; Park, Byung Ran; Yang, Dong Cheol; Im, Ju Hyeon; Kang, In Young

    1998-01-01

    To evaluate the ultrasonographic and CT findings of hepatosplenic tuberculosis Materials and Methods: We retrospectively reviewed the ultrasonographic and CT findings of confirmed hepatosplenic tuberculosis in 12 patients. Six were men and six were women ; their average age was 41, and most were in their twenties. Lesions of the liver and spleen, as well as associated findings such as abdominal tuberculosis and other organ involvement of tuberculosis were analyzed. Results : There were three cases of hepatic tuberculosis, seven of splenic tuberculosis, and two of hepatosplenic involvement of tuberculosis. On the basis of the ultrasonographic and CT findings, hepatosplenic tuberculosis was classified as one of two patterns : miliary or micronodular, ormacronodular. The micronodular type was more common (9/12 cases) being characterized by innumerable micronodules,and with easy coalescence in the liver and spleen in five of the nine cases. The macronodular type of low density mass was noted in the other three patients. Splenomegaly was noted in 12 cases and hepatomegaly in ten. Pulmonary tuberculosis-including the miliary type(n=5)-was noted in eight patients. Associated abdominal tuberculosis such as lymphadenopathy with central low density and peripheral rim enhancement (n=6), tuberculous peritonitis(n=3),highly attenuated ascites(n=6), adrenal tuberculosis(n=1), renal tuberculosis(n=1), ovarian abscess(n=1), psoasabscess(n=1), and systemic tuberculosis such as central nervous system tuberculoma(n=2), cervical lymphadenopathy(n=4) and tuberculous spondylitis(n=1) were noted. Conclusion : Ultrasonography and CT were valuable in the detection and diagnosis of hepatosplenic tuberculosis

  2. Ultrasonographic and CT findings of hepatosplenic tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Un Hyeon; Lee, Jeong Seok; Ko, Kang Seok; Park, Byung Ran; Yang, Dong Cheol; Im, Ju Hyeon [Kwangju Christian Hospital, Kwangju (Korea, Republic of); Kang, In Young [Kwangju Green Cross Hospital, Kwangju (Korea, Republic of)

    1998-08-01

    To evaluate the ultrasonographic and CT findings of hepatosplenic tuberculosis Materials and Methods: We retrospectively reviewed the ultrasonographic and CT findings of confirmed hepatosplenic tuberculosis in 12 patients. Six were men and six were women ; their average age was 41, and most were in their twenties. Lesions of the liver and spleen, as well as associated findings such as abdominal tuberculosis and other organ involvement of tuberculosis were analyzed. Results : There were three cases of hepatic tuberculosis, seven of splenic tuberculosis, and two of hepatosplenic involvement of tuberculosis. On the basis of the ultrasonographic and CT findings, hepatosplenic tuberculosis was classified as one of two patterns : miliary or micronodular, ormacronodular. The micronodular type was more common (9/12 cases) being characterized by innumerable micronodules,and with easy coalescence in the liver and spleen in five of the nine cases. The macronodular type of low density mass was noted in the other three patients. Splenomegaly was noted in 12 cases and hepatomegaly in ten. Pulmonary tuberculosis-including the miliary type(n=5)-was noted in eight patients. Associated abdominal tuberculosis such as lymphadenopathy with central low density and peripheral rim enhancement (n=6), tuberculous peritonitis(n=3),highly attenuated ascites(n=6), adrenal tuberculosis(n=1), renal tuberculosis(n=1), ovarian abscess(n=1), psoasabscess(n=1), and systemic tuberculosis such as central nervous system tuberculoma(n=2), cervical lymphadenopathy(n=4) and tuberculous spondylitis(n=1) were noted. Conclusion : Ultrasonography and CT were valuable in the detection and diagnosis of hepatosplenic tuberculosis.

  3. CT findings of diffuse malignant leptomeningeal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Katsuro; Sahashi, Ko; Takahashi, Akira; Nakagawa, Hiroshi [Aichi Medical Univ., Aichi (Japan); Sumi, Yasuhiko

    1982-04-01

    This was a case of malignant melanoma which spreaded diffusely in the meninges. The diagnosis was established by cytology of the cerebrospinal fluid. The CT images, cerebral angiographic findings and pathological findings by autopsy were presented.

  4. Renal and perirenal non-Hodgkin's lymphoma: CT findings

    International Nuclear Information System (INIS)

    Lee, Seon Kyu; Kim, Seung Hyup; Lee, Goo; Choi, Byeung In; Han, Man Chung

    1992-01-01

    CT findings of 19 kidneys in 12 patients with renal and perirenal non-Hodgkin's lymphoma were retrospectively reviewed to determine distinguishing characteristic and specific findings. CT manifestation of the renal and perirenal lymphoma included multiple nodules in five kidneys(26.3%), trans-capsular infiltration in three kidneys(15.8%), trans-sinus infiltration in nine kidneys(47.4%) and diffuse infiltration in two kidneys(10.5%). Perirenal changes were thickening of the renal fascia in ten kidneys(52.6%) and crescent lesion of low attenuation in the subcapsular area in five kidneys(26.3%) Retroperitoneal lymphadenopathy was evident in eleven patient(57.9%). Renal calyceal dilatation without renal pelvic dilatation(selective calycelal dilatation) was noted in three kidneys. Familiarity with these CT findings of renal and perirenal lymphoma may be helpful in the diagnosis and management of patient with non-Hodgkin's lymphoma

  5. Perforated appendicitis: accuracy of CT diagnosis and correlation of CT findings with the length of hospital

    International Nuclear Information System (INIS)

    Siddiqui, H.A.; Afzal, S.

    2007-01-01

    To determine the sensitivity and specificity of CT findings in the differentiation of perforated from nonperforated appendicitis and correlate CT diagnosis with the length of hospital stay. The study included 70 patients who presented with right lower quadrant abdominal pain and underwent preoperative CT scan followed by appendectomy. Patients were divided into two groups of having perforated and nonperforated appendicitis on the basis of CT scan findings. The surgical and pathological reports combined were considered the reference standard for the diagnosis of perforated appendicitis. Various CT scan findings and average duration of hospital stay in days was compared by t-test. Twenty-six (37%) of 70 patients had perforated appendicitis. It was correctly identified on pre-operative CT scan in 18 patients. There were 18 true positive diagnoses, 43 true negative diagnoses, 1 false positive diagnosis and 8 false negative diagnoses which yielded a sensitivity of 69%, specificity of 97%, positive predictive value of 94% and negative predictive value of 84%. Mean length of hospital stay in perforated group was 6.3 days and 2.9 days in nonperforated group. Severe periappendiceal inflammation, periappendiceal and or abdominopelvic fluid and abscess were significantly associated with perforated appendicitis and with a significant longer hospital stay (p <.001). CT scan is 69% sensitive and 97% specific for the diagnosis of perforated appendicitis and constellation of CT findings can be used to select patients with perforated appendicitis for initial non-operative management. Presence of CT signs of significant appendiceal inflammation is independent predictor of longer hospital stay. (author)

  6. Acute gynecologic disorders in adolescents: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Tong [Soonchunhyang Univ. Cheonan Hospital/Soonchunhyang Univ. College of Medicine, Cheonan (Korea, Republic of)

    2012-09-15

    Gynecologic disorders that cause pelvic pain in adolescents include hemorrhagic ovarian cysts, rupture or torsion of ovarian cyst or tumors, hematocolpos caused by vaginal obstruction, endometriosis, cystic uterine adenomyosis, pelvic inflammatory diseases, and pelvic inclusion cyst. The use of CT for the evaluation of pelvic pain is increasing, and CT is useful if ultrasound findings are not decisive and the lesion is extensive.

  7. CT findings in Arnold-Chiari malformation

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Y.; Nakamura, S. (Aichi Prefecture Colony, Kasugai (Japan). Central Hospital); Yamada, H.; Kageyama, N.

    1981-12-01

    CT scans of Arnold-Chiari malformations demonstrate many abnormal findings that are considered to be specific for this type of malformation. Fifty patients with Arnold-Chiari malformations were studied, and their CT findings were analyzed. This number included 14 preshunted neonatal cases and 36 post-shunted infantile cases. Craniolacunia was recognized only in the neonatal cases, but other skull changes, including scaphocephaly and petrous scalloping, were found more frequently in the infantile cases. The posterior fossa abnormality was composed of several specific changes, such as a non-visualized fourth ventricle, a lateral or upward growth of the cerebellum, or a beaking deformity of the midbrain. These findings were far more common in the infantile cases. However, in 7 neonatal cases on which CT cisternography was performed, these posterior fossa changes were well recognized in the majority of cases. Hydrocephalus was found in all cases. In half of the post-shunted infantile cases, the lateral ventricles were markedly collapsed. Characteristic features of the lateral ventricles, such as a protruding of the caudate nuclei, a pointing of the frontal and/or occipital horns, an absent septum pellucidum, or dominently dilated occipital horns, were commonly found in both neonatal and infantile cases. The subarachnoid space was remarkably widened at the retrothalamic cistern and/or the interhemispheric fissure in many cases.

  8. CT findings of overian teratomas : mature versus immature

    International Nuclear Information System (INIS)

    Kim, Jong Chul; Kim, Young Wol

    1996-01-01

    To differentiate mature and immature ovarian teratomas, using CT findings. The CT findings of ten mature ovarian teratomas (in one patient, bilateral) and ten which were immature were compared, using statistical analysis. Images were evaluated for size, margins, architecture, contents (mural nodules, fat, calcification), septa, local invasion and distant metastasis. These findings were compared with pathologic findings. Of the ten mature tumors, nine were well defined and predominantly cystic in internal architecture, and one was mixed. Mural nodules were found in six tumor, fat in all, distinct calcification in seven, and regular septa in three lesions. Of the ten immature humors, eight had irregular margins. Seven were predominantly solid in internal architecture and irregularly enhanced, two were mixed, and one was mainly cystic. Fat was detected in five lesions, indistinct scattered calcification in six, irregular septa in three, and local invasion of distant metastasis in four patients. Compared with mature ovarian teratomas, those that are immature tend to show CT findings of marginal irregularity, solid mass with irregular enhacement, scattered indistinct calcifications, septal irregularity, local invasion or distant metastasis. Our experience suggests that these findings may be helpful in differentiation of mature and immature ovarian teratomas

  9. TU-G-207-01: CT Imaging Using Energy-Sensitive Photon-Counting Detectors

    International Nuclear Information System (INIS)

    Taguchi, K.

    2015-01-01

    Last few years has witnessed the development of novel of X-ray imaging modalities, such as spectral CT, phase contrast CT, and X-ray acoustic/fluorescence/luminescence imaging. This symposium will present the recent advances of these emerging X-ray imaging modalities and update the attendees with knowledge in various related topics, including X-ray photon-counting detectors, X-ray physics underlying the emerging applications beyond the traditional X-ray imaging, image reconstruction for the novel modalities, characterization and evaluation of the systems, and their practical implications. In addition, the concept and practical aspects of X-ray activatable targeted nanoparticles for molecular X-ray imaging will be discussed in the context of X-ray fluorescence and luminescence CT. Learning Objectives: Present background knowledge of various emerging X-ray imaging techniques, such as spectral CT, phase contrast CT and X-ray fluorescence/luminescence CT. Discuss the practical need, technical aspects and current status of the emerging X-ray imaging modalities. Describe utility and future impact of the new generation of X-ray imaging applications

  10. CT scan findings of fungal pneumonia

    International Nuclear Information System (INIS)

    Heckmann, M.; Uder, M.; Bautz, W.; Heinrich, M.

    2008-01-01

    The importance of fungal infection of the lung in immunocompromised patients has increased substantially during the last decades. Numerically the most patients are those with neutropenia, e.g. patients with malignancies or solid organ and stem cell transplantation, chemotherapy, corticosteroid use and HIV infection. Although fungal infections can occur in immunocompetent patients, their frequency in this population is rare. The clinical symptoms such as fever accompanied with non-productive cough are unspecific. In some patients progression to hypoxemia and dyspnea may occur rapidly. In spite of improved antifungal therapy morbidity and mortality of these infections are still high. Therefore an early and non-invasive diagnosis is very important. That is why CT and even better High-Resolution-CT (HR-CT) is a very important modality in examining immunocompromised patients with a probability of fungal infection. CT is everywhere available and, as a non-invasive method, able to give the relevant diagnose efficiently. This paper should give an overview about the radiologic findings and possible differential diagnosis of diverse pulmonary fungal infections in CT. Pneumonias caused by Aspergillus, Cryptococcus, Candida, Histoplasma, Mucor and Geotrichum capitatum are illustrated. (orig.)

  11. Evaluation of K x-ray escape and crosstalk in CdTe detectors and multi-channel detectors

    International Nuclear Information System (INIS)

    Ohtsuchi, Tetsuro; Ohmori, Koichi; Tsutsui, Hiroshi; Baba, Sueki

    1995-01-01

    The simple structure of CdTe semiconductor detectors facilitates their downsizing, and their possible application to radiographic sensors has been studied. The escape of K X-rays from these detectors increases with reduction of their dimensions and affects the measurements of X- and gamma-ray spectra. K X-rays also produce crosstalk in multi-channel detectors with adjacent channels. Therefore, K X-rays which escape from the detector elements degrade both the precision of energy spectra and spatial resolution. The ratios of escape peak integrated counts to total photon counts for various sizes of CdTe single detectors were calculated for gamma rays using the Monte Carlo method. Also, escape and crosstalk ratios were simulated for the CdTe multi-channel detectors. The theoretical results were tested experimentally for 59.54-keV gamma rays from a 241 Am radioactive source. Results showed that escape ratios for single detectors were strongly dependent on element size and thickness. The escape and crosstalk ratios increased with closer channel pitch. The calculated results showed a good agreement with the experimental data. The calculations made it clear that K X-rays which escaped to neighboring channels induced crosstalk more frequently at smaller channel pitch in multichannel detectors. A radiation shielding grid which blocked incident photons between the boundary channels was also tested by experiment and by calculation. It was effective in reducing the probability of escape and crosstalk

  12. Functional imaging of larynx via 256-Slice Multi-Detector Computed Tomography in patients with laryngeal tumors: A faster, better and more reliable pre-therapeutic evaluation

    International Nuclear Information System (INIS)

    Celebi, Irfan; Basak, Muzaffer; Ucgul, Ayhan; Yildirim, Hakan; Oz, Aysel; Vural, Cetin

    2012-01-01

    Objective: To determine the clinical utility of using dynamic maneuvers during imaging of larynx via 256-Slice Multi-Detector Computed Tomography in the pre-therapeutic evaluation of laryngeal tumors. Materials and methods: A total of 27 patients (7 women, 20 men; aged 53–76 years) diagnosed with laryngeal squamous cell carcinoma were evaluated pre-therapeutically via contrast enhanced axial CT scans during consecutive phases of phonation (PP), inspiration (IP) and Valsalva maneuver (VP). Results: In 2 of 5 patients diagnosed with T1a glottic tumor, scans obtained during VP and PP were normal while the CT scans obtained during IP clearly showed a mass. In all patients (27/27) PP provided visualization of the ventricle, on coronal plane images and the pyriform sinus apices, on axial plane images. Involvement of the anterior commissure was best assessable on axial plane IP images (sensitivity 93%, specificity 92%). In cases of stage T1–T3 tumors use of dynamic maneuvers during laryngeal CT imaging showed the location and extension of the tumor better than the single phase CT scans did. We did not find a significant improvement in the pre-therapeutic evaluation in stage T4 tumors. Conclusion: Providing markedly clearer and more detailed evaluation of mucosal surfaces and deep structures of the larynx and mobility of the cords than do conventional scans, use of dynamic laryngeal maneuvers during laryngeal CT imaging seems to be an useful alternative in the pre-therapeutic assessment of laryngeal tumors.

  13. High-resolution CT findings in Streptococcus milleri pulmonary infection

    International Nuclear Information System (INIS)

    Okada, F.; Ono, A.; Ando, Y.; Nakayama, T.; Ishii, H.; Hiramatsu, K.; Sato, H.; Kira, A.; Otabe, M.; Mori, H.

    2013-01-01

    Aim: To assess pulmonary high-resolution computed tomography (CT) findings in patients with acute Streptococcus milleri pulmonary infection. Materials and methods: Sixty consecutive patients with acute S. milleri pneumonia who had undergone high-resolution CT chest examinations between January 2004 and March 2010 were retrospectively identified. Twenty-seven patients with concurrent infections were excluded. The final study group comprised 33 patients (25 men, 8 women; aged 20–88 years, mean 63.1 years) with S. milleri infection. The patients' clinical findings were assessed. Parenchymal abnormalities, enlarged lymph nodes, and pleural effusion were evaluated on high-resolution CT. Results: Underlying conditions included malignancy (n = 15), a smoking habit (n = 11), and diabetes mellitus (n = 8). CT images of all patients showed abnormal findings, including ground-glass opacity (n = 24), bronchial wall thickening (n = 23), consolidation (n = 17), and cavities (n = 7). Pleural effusion was found in 18 patients, and complex pleural effusions were found in seven patients. Conclusion: Pulmonary infection caused by S. milleri was observed mostly in male patients with underlying conditions such as malignancy or a smoking habit. The CT findings in patients with S. milleri consisted mainly of ground-glass opacity, bronchial wall thickening, pleural effusions, and cavities

  14. Dose reduction strategies for cardiac CT

    International Nuclear Information System (INIS)

    Midgley, S.M.; Einsiedel, P.; Langenberg, F.; Lui, E.

    2010-01-01

    Full text: Recent advances in CT technology have produced brighter X-ray sources. gantries capable of increased rotation speeds, faster scintil lation materials arranged into multiple rows of detectors, and associated advances in 3D reconstruction methods. These innovations have allowed multi-detector CT to be turned to the diagnosis of cardiac abnormalities and compliment traditional imaging techniques such as coronary angiography. This study examines the cardiac imaging solution offered by the Siemens Somatom Definition Dual Source 64 slice CT scanner. Our dose reduction strategies involve optimising the data acquisition protocols according to diagnostic task, patient size and heart rate. The relationship between scan parameters, image quality and patient dose is examined and verified against measurements with phantoms representing the standard size patient. The dose reduction strategies are reviewed with reference to survey results of patient dose. Some cases allow the insertion of shielding to protect radiosensitive organs, and results are presented to quantify the dose saving.

  15. CT findings of necrotizing pneumonia

    International Nuclear Information System (INIS)

    Kim, Hyae Young; Im, Jung Gi; Whang, Sung Il; Cheon, Jung Eun; Lee, Jae Kyo; Song, Jae Woo

    1998-01-01

    Necrotizing pneumonia causes necrosis of pulmonary parenchyma and may lead to pulmonary gangrene. Prior to the antibiotic era, extensive pulmonary involvement was potentially fatal, but the incidence of necrotizing pneumoniais now less common. On contrast-enhanced CT scans, consolidation with contrast enhancement containing necrotic foci with low attenuation and cavities is characteristic. Radiologic findings do not differ according to the causative organism and in most of cases, specific diagnosis may be impossible. Clinical findings and certain characteristic radiologic findings may be helpful for narrowing the differential diagnosis. We illustrate the clinical and radiologic characteristics of necrotizing pneumonia according to causative bacterial organisms

  16. Dynamic CT findings of pulmonary hamartoma: A comparison with histopathologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Wanglae; Jeong, Yeon Joo; Lee, Chang Hun; Lee, Ji Won; Kim, Yeong Dae [Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan (Korea, Republic of); Kim, Kun Il [Dept. of Radiology, Pusan National University Yangsan Hospital, Pusan National University School of Medicine and Medical Research Institute, Yangsan (Korea, Republic of)

    2013-12-15

    Describe the dynamic CT findings of pulmonary hamartoma and to compare these findings with histopathologic findings. he Institutional Review Board approved this retrospective study and the requirement for patient informed consent was waived. The hemodynamic CT features of 11 patients (M : F = 6 : 5; mean age, 53.6 years) with pathologically proven pulmonary hamartoma were evaluated. All 11 patients underwent enhanced dynamic CT using a helical technique. A series of images were obtained throughout each nodule with 2.5-mm collimation at 0, 30, 60, 90 and 120 seconds and at 4, 5 and 15 minutes after an intravenous injection of contrast medium. Extents and patterns of enhancement were correlated with histologic tumor components. ll 11 tumors showed persistent enhancement with variable degrees of net enhancement [mean tumor peak enhancement, 48.6 ± 19.0 Hounsfield unit (HU); mean tumor net enhancement, 31.9 ± 11.8 HU] and thick capsular and septal enhancement. Histologically, all 11 tumors were composed of mature cartilage and loose mesenchymal tissue. A significant positive correlation was found between the net enhancement values and loose connective tissue component percentages (r = 0.749, p = 0.008); further, a negative correlation was found between the net enhancement values and cartilaginous component percentages (r = -0.813, p = 0.002). n dynamic CT, hamartoma exhibited persistent enhancement without washout as well as thick capsular and septal enhancements. Net enhancement values were found to be positively correlated with the proportion of the loose connective tissue component. Thick capsular and septal enhancements were attributed histopathologically to loose connective tissue, separating tumors into cartilaginous lobules.

  17. Dynamic CT findings of pulmonary hamartoma: A comparison with histopathologic findings

    International Nuclear Information System (INIS)

    Cho, Wanglae; Jeong, Yeon Joo; Lee, Chang Hun; Lee, Ji Won; Kim, Yeong Dae; Kim, Kun Il

    2013-01-01

    Describe the dynamic CT findings of pulmonary hamartoma and to compare these findings with histopathologic findings. he Institutional Review Board approved this retrospective study and the requirement for patient informed consent was waived. The hemodynamic CT features of 11 patients (M : F = 6 : 5; mean age, 53.6 years) with pathologically proven pulmonary hamartoma were evaluated. All 11 patients underwent enhanced dynamic CT using a helical technique. A series of images were obtained throughout each nodule with 2.5-mm collimation at 0, 30, 60, 90 and 120 seconds and at 4, 5 and 15 minutes after an intravenous injection of contrast medium. Extents and patterns of enhancement were correlated with histologic tumor components. ll 11 tumors showed persistent enhancement with variable degrees of net enhancement [mean tumor peak enhancement, 48.6 ± 19.0 Hounsfield unit (HU); mean tumor net enhancement, 31.9 ± 11.8 HU] and thick capsular and septal enhancement. Histologically, all 11 tumors were composed of mature cartilage and loose mesenchymal tissue. A significant positive correlation was found between the net enhancement values and loose connective tissue component percentages (r = 0.749, p = 0.008); further, a negative correlation was found between the net enhancement values and cartilaginous component percentages (r = -0.813, p = 0.002). n dynamic CT, hamartoma exhibited persistent enhancement without washout as well as thick capsular and septal enhancements. Net enhancement values were found to be positively correlated with the proportion of the loose connective tissue component. Thick capsular and septal enhancements were attributed histopathologically to loose connective tissue, separating tumors into cartilaginous lobules.

  18. TH-CD-207B-06: Swank Factor of Segmented Scintillators in Multi-Slice CT Detectors: Pulse Height Spectra and Light Escape

    Energy Technology Data Exchange (ETDEWEB)

    Howansky, A; Peng, B; Lubinsky, A; Zhao, W [Stony Brook University, Stony Brook, NY (United States)

    2016-06-15

    Purpose: Pulse height spectra (PHS) have been used to determine the Swank factor of a scintillator by measuring fluctuations in its light output per x-ray interaction. The Swank factor and x-ray quantum efficiency of a scintillator define the upper limit to its imaging performance, i.e. DQE(0). The Swank factor below the K-edge is dominated by optical properties, i.e. variations in light escape efficiency from different depths of interaction, denoted e(z). These variations can be optimized to improve tradeoffs in x-ray absorption, light yield, and spatial resolution. This work develops a quantitative model for interpreting measured PHS, and estimating e(z) on an absolute scale. The method is used to investigate segmented ceramic GOS scintillators used in multi-slice CT detectors. Methods: PHS of a ceramic GOS plate (1 mm thickness) and segmented GOS array (1.4 mm thick) were measured at 46 keV. Signal and noise propagation through x-ray conversion gain, light escape, detection by a photomultiplier tube and dynode amplification were modeled using a cascade of stochastic gain stages. PHS were calculated with these expressions and compared to measurements. Light escape parameters were varied until modeled PHS agreed with measurements. The resulting estimates of e(z) were used to calculate PHS without measurement noise to determine the inherent Swank factor. Results: The variation in e(z) was 67.2–89.7% in the plate and 40.2–70.8% in the segmented sample, corresponding to conversion gains of 28.6–38.1 keV{sup −1} and 17.1–30.1 keV{sup −1}, respectively. The inherent Swank factors of the plate and segmented sample were 0.99 and 0.95, respectively. Conclusion: The high light escape efficiency in the ceramic GOS samples yields high Swank factors and DQE(0) in CT applications. The PHS model allows the intrinsic optical properties of scintillators to be deduced from PHS measurements, thus it provides new insights for evaluating the imaging performance of

  19. The relationship between image quality and CT dose index of multi-slice low-dose chest CT

    International Nuclear Information System (INIS)

    Zhu Xiaohua; Shao Jiang; Shi Jingyun; You Zhengqian; Li Shijun; Xue Yongming

    2003-01-01

    Objective: To explore the rationality and possibility of multi-slice low-dose CT scan in the examination of the chest. Methods: (1) X-ray dose index measurement: 120 kV tube voltage, 0.75 s rotation, 8 mm and 3 mm slice thickness, and the tube current setting of 115.0, 40.0, 25.0, and 7.5 mAs were employed in every section. The X-ray radiation dose was measured and compared statistically. (2) phantom measurement of homogeneity and noise: The technical parameters were 120 kV, 0.75 s, 8 mm and 3 mm sections, and every slice was scanned using tube current of 115.0, 40.0, 25.0, and 7.5 mAs. Five same regions of interest were measured on every image. The homogeneity and noise level of CT were appraised. (3) The multi-slice low-dose CT in patients: 30 patients with mass and 30 with patch shadow in the lung were selected randomly. The technical parameters were 120 kV, 0.75 s, 8 mm and 3 mm slice thickness. 115.0, 40.0, 25.0, 15.0, and 7.5 mAs tube current were employed in each same slice. Otherwise, 15 cases with helical scan were examined using 190, 150, 40, 25, and 15 mAs tube current. The reconstruction images of MIP, MPR, CVR, HRCT, 3D, CT virtual endoscopy, and variety of interval reconstruction were compared. (4) Evaluation of image quality: CT images were evaluated by four doctors using single-blind method, and 3 degrees including normal image, image with few artifact, and image with excessive artifact, were employed and analyzed statistically. Results: (1) The CT dose index with 115.0 mAs tube current exceeded those of 40.0, 25.0, and 7.5 mAs by about 60%, 70%, and 85%, respectively. (2) The phantom measurement showed that the lower of CT dose the lower of homogeneity, the lower of CT dose the higher of noise level. (3) Result of image quality evaluation: The percentage of the normal image had no significant difference between 8 and 3 mm in 115, 40, and 25 mAs (P>0.05). Conclusion: Multi-slice low-dose chest CT technology may protect the patients and guarantee the

  20. CT findings in gastrocolic fistula following percutaneous endoscopic gastrostomy

    International Nuclear Information System (INIS)

    Brown, Suki; McHugh, Kieran; Ledermann, Sarah; Pierro, Agostino

    2007-01-01

    We describe the CT findings in an initially asymptomatic boy aged 2 years 9 months with a gastrocolic fistula following percutaneous endoscopic gastrostomy (PEG) placement. The findings consisted of an unusual configuration of the gastrostomy tubing on an abdominal radiograph and upper gastrointestinal study indicating the possibility of transcolic PEG placement, which was confirmed with limited section CT. This well-known and major complication following a common procedure may be recognized on plain abdominal radiography, but it has not to our knowledge been documented previously on CT in a child. (orig.)

  1. CT findings in gastrocolic fistula following percutaneous endoscopic gastrostomy

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Suki [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); St. George' s Hospital, Radiology Department, London (United Kingdom); McHugh, Kieran [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Ledermann, Sarah [Great Ormond Street Hospital for Children, Department of Nephrology, London (United Kingdom); Pierro, Agostino [Great Ormond Street Hospital for Children, Department of Surgery, London (United Kingdom)

    2007-02-15

    We describe the CT findings in an initially asymptomatic boy aged 2 years 9 months with a gastrocolic fistula following percutaneous endoscopic gastrostomy (PEG) placement. The findings consisted of an unusual configuration of the gastrostomy tubing on an abdominal radiograph and upper gastrointestinal study indicating the possibility of transcolic PEG placement, which was confirmed with limited section CT. This well-known and major complication following a common procedure may be recognized on plain abdominal radiography, but it has not to our knowledge been documented previously on CT in a child. (orig.)

  2. CT findings of respiratory bronchiolitis caused by cigarette smoking

    Energy Technology Data Exchange (ETDEWEB)

    Katagiri, Siro; Osima, K.; Kim, S. [Chiba Tokusyukai Hospital, Funabashi (Japan)

    1998-07-01

    CT scans were performed in 11 cases of respiratory bronchiolitis caused by cigarette smoking. Characteristics of CT findings were as follows: Remarkable visualization of the branching in peripheral bronchi within secondary lobules, multiple ground-glass opacities of centrilobular or lobular size adjacent to the above mentioned bronchial branching, thickening of the bronchial wall without dilatation, and no or minimal centrilobular emphysema. These characteristic CT findings were observed in all of 11 cases, who are current smokers, and never observed in non-smokers, ex-smokers and patients with apparent centrilobular emphysema. (author)

  3. CT findings of respiratory bronchiolitis caused by cigarette smoking

    International Nuclear Information System (INIS)

    Katagiri, Siro; Osima, K.; Kim, S.

    1998-01-01

    CT scans were performed in 11 cases of respiratory bronchiolitis caused by cigarette smoking. Characteristics of CT findings were as follows: Remarkable visualization of the branching in peripheral bronchi within secondary lobules, multiple ground-glass opacities of centrilobular or lobular size adjacent to the above mentioned bronchial branching, thickening of the bronchial wall without dilatation, and no or minimal centrilobular emphysema. These characteristic CT findings were observed in all of 11 cases, who are current smokers, and never observed in non-smokers, ex-smokers and patients with apparent centrilobular emphysema. (author)

  4. Generalized multi-dimensional adaptive filtering for conventional and spiral single-slice, multi-slice, and cone-beam CT

    International Nuclear Information System (INIS)

    Kachelriess, Marc; Watzke, Oliver; Kalender, Willi A.

    2001-01-01

    In modern computed tomography (CT) there is a strong desire to reduce patient dose and/or to improve image quality by increasing spatial resolution and decreasing image noise. These are conflicting demands since increasing resolution at a constant noise level or decreasing noise at a constant resolution level implies a higher demand on x-ray power and an increase of patient dose. X-ray tube power is limited due to technical reasons. We therefore developed a generalized multi-dimensional adaptive filtering approach that applies nonlinear filters in up to three dimensions in the raw data domain. This new method differs from approaches in the literature since our nonlinear filters are applied not only in the detector row direction but also in the view and in the z-direction. This true three-dimensional filtering improves the quantum statistics of a measured projection value proportional to the third power of the filter size. Resolution tradeoffs are shared among these three dimensions and thus are considerably smaller as compared to one-dimensional smoothing approaches. Patient data of spiral and sequential single- and multi-slice CT scans as well as simulated spiral cone-beam data were processed to evaluate these new approaches. Image quality was assessed by evaluation of difference images, by measuring the image noise and the noise reduction, and by calculating the image resolution using point spread functions. The use of generalized adaptive filters helps to reduce image noise or, alternatively, patient dose. Image noise structures, typically along the direction of the highest attenuation, are effectively reduced. Noise reduction values of typically 30%-60% can be achieved in noncylindrical body regions like the shoulder. The loss in image resolution remains below 5% for all cases. In addition, the new method has a great potential to reduce metal artifacts, e.g., in the hip region

  5. WE-B-207-02: CT Lung Cancer Screening and the Medical Physicist: A Dosimetry Summary of CT Participants in the National Lung Cancer Screening Trial (NLST)

    International Nuclear Information System (INIS)

    Lee, C.

    2015-01-01

    The US National Lung Screening Trial (NLST) was a multi-center randomized, controlled trial comparing a low-dose CT (LDCT) to posterior-anterior (PA) chest x-ray (CXR) in screening older, current and former heavy smokers for early detection of lung cancer. Recruitment was launched in September 2002 and ended in April 2004 when 53,454 participants had been randomized at 33 screening sites in equal proportions. Funded by the National Cancer Institute this trial demonstrated that LDCT screening reduced lung cancer mortality. The US Preventive Services Task Force (USPSTF) cited NLST findings and conclusions in its deliberations and analysis of lung cancer screening. Under the 2010 Patient Protection and Affordable Care Act, the USPSTF favorable recommendation regarding lung cancer CT screening assisted in obtaining third-party payers coverage for screening. The objective of this session is to provide an introduction to the NLST and the trial findings, in addition to a comprehensive review of the dosimetry investigations and assessments completed using individual NLST participant CT and CXR examinations. Session presentations will review and discuss the findings of two independent assessments, a CXR assessment and the findings of a CT investigation calculating individual organ dosimetry values. The CXR assessment reviewed a total of 73,733 chest x-ray exams that were performed on 92 chest imaging systems of which 66,157 participant examinations were used. The CT organ dosimetry investigation collected scan parameters from 23,773 CT examinations; a subset of the 75,133 CT examinations performed using 97 multi-detector CT scanners. Organ dose conversion coefficients were calculated using a Monte Carlo code. An experimentally-validated CT scanner simulation was coupled with 193 adult hybrid computational phantoms representing the height and weight of the current U.S. population. The dose to selected organs was calculated using the organ dose library and the abstracted scan

  6. WE-B-207-02: CT Lung Cancer Screening and the Medical Physicist: A Dosimetry Summary of CT Participants in the National Lung Cancer Screening Trial (NLST)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C. [National Cancer Institute (United States)

    2015-06-15

    The US National Lung Screening Trial (NLST) was a multi-center randomized, controlled trial comparing a low-dose CT (LDCT) to posterior-anterior (PA) chest x-ray (CXR) in screening older, current and former heavy smokers for early detection of lung cancer. Recruitment was launched in September 2002 and ended in April 2004 when 53,454 participants had been randomized at 33 screening sites in equal proportions. Funded by the National Cancer Institute this trial demonstrated that LDCT screening reduced lung cancer mortality. The US Preventive Services Task Force (USPSTF) cited NLST findings and conclusions in its deliberations and analysis of lung cancer screening. Under the 2010 Patient Protection and Affordable Care Act, the USPSTF favorable recommendation regarding lung cancer CT screening assisted in obtaining third-party payers coverage for screening. The objective of this session is to provide an introduction to the NLST and the trial findings, in addition to a comprehensive review of the dosimetry investigations and assessments completed using individual NLST participant CT and CXR examinations. Session presentations will review and discuss the findings of two independent assessments, a CXR assessment and the findings of a CT investigation calculating individual organ dosimetry values. The CXR assessment reviewed a total of 73,733 chest x-ray exams that were performed on 92 chest imaging systems of which 66,157 participant examinations were used. The CT organ dosimetry investigation collected scan parameters from 23,773 CT examinations; a subset of the 75,133 CT examinations performed using 97 multi-detector CT scanners. Organ dose conversion coefficients were calculated using a Monte Carlo code. An experimentally-validated CT scanner simulation was coupled with 193 adult hybrid computational phantoms representing the height and weight of the current U.S. population. The dose to selected organs was calculated using the organ dose library and the abstracted scan

  7. Integrated visualization of multi-angle bioluminescence imaging and micro CT

    NARCIS (Netherlands)

    Kok, P.; Dijkstra, J.; Botha, C.P.; Post, F.H.; Kaijzel, E.; Que, I.; Löwik, C.W.G.M.; Reiber, J.H.C.; Lelieveldt, B.P.F.

    2007-01-01

    This paper explores new methods to visualize and fuse multi-2D bioluminescence imaging (BLI) data with structural imaging modalities such as micro CT and MR. A geometric, back-projection-based 3D reconstruction for superficial lesions from multi-2D BLI data is presented, enabling a coarse estimate

  8. Interferometric direction finding with a metamaterial detector

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesh, Suresh; Schurig, David, E-mail: david.schurig@utah.edu [Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Shrekenhamer, David; Padilla, Willie [Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States); Xu, Wangren; Sonkusale, Sameer [Department of Electrical and Computer Engineering, Tufts University, Medford, Massachusetts 02155 (United States)

    2013-12-16

    We present measurements and analysis demonstrating useful direction finding of sources in the S band (2–4 GHz) using a metamaterial detector. An augmented metamaterial absorber that supports magnitude and phase measurement of the incident electric field, within each unit cell, is described. The metamaterial is implemented in a commercial printed circuit board process with off-board back-end electronics. We also discuss on-board back-end implementation strategies. Direction finding performance is analyzed for the fabricated metamaterial detector using simulated data and the standard algorithm, MUtiple SIgnal Classification. The performance of this complete system is characterized by its angular resolution as a function of radiation density at the detector. Sources with power outputs typical of mobile communication devices can be resolved at kilometer distances with sub-degree resolution and high frame rates.

  9. Effects of dose reduction on multi-detector computed tomographic images in evaluating the maxilla and mandible for pre-surgical implant planning: a cadaveric study.

    Science.gov (United States)

    Koizumi, Hiroshi; Sur, Jaideep; Seki, Kenji; Nakajima, Koh; Sano, Tsukasa; Okano, Tomohiro

    2010-08-01

    To assess effects of dose reduction on image quality in evaluating maxilla and mandible for pre-surgical implant planning using cadavers. Six cadavers were used for the study using multi-detector computed tomography (CT) operated at 120 kV and the variable tube current of 80, 40, 20 and 10 mA. A slice thickness of 0.625 mm and pitch 1 were used. Multi-planar images perpendicular and parallel to dentitions were created. The images were evaluated by five oral radiologists in terms of visibility of the anatomical landmarks including alveolar crest, mandibular canal, floors of the maxillary sinus and nasal cavity, contours/cortical layer of jaw bones and the details of trabecular bone. Observers were asked to determine the quality of the images in comparison with 80 mA images based on the criteria: excellent, good, fair or non-diagnostic. The average scores of all observers were calculated for each specimen in all exposure conditions. The 40 mA images could visualize such landmarks and were evaluated to be same or almost equivalent in quality to the 80 mA images. Even the 20 mA images could be accepted just for diagnostic purpose for implant with substantial deterioration of the image quality. The 10 mA images may not be accepted because of the obscured contour caused by image noise. Significant dose reduction by lowering mA can be utilized for pre-surgical implant planning in multi-detector CT.

  10. Performance simulation of an x-ray detector for spectral CT with combined Si and Cd[Zn]Te detection layers.

    Science.gov (United States)

    Herrmann, Christoph; Engel, Klaus-Jürgen; Wiegert, Jens

    2010-12-21

    The most obvious problem in obtaining spectral information with energy-resolving photon counting detectors in clinical computed tomography (CT) is the huge x-ray flux present in conventional CT systems. At high tube voltages (e.g. 140 kVp), despite the beam shaper, this flux can be close to 10⁹ Mcps mm⁻² in the direct beam or in regions behind the object, which are close to the direct beam. Without accepting the drawbacks of truncated reconstruction, i.e. estimating missing direct-beam projection data, a photon-counting energy-resolving detector has to be able to deal with such high count rates. Sub-structuring pixels into sub-pixels is not enough to reduce the count rate per pixel to values that today's direct converting Cd[Zn]Te material can cope with (≤ 10 Mcps in an optimistic view). Below 300 µm pixel pitch, x-ray cross-talk (Compton scatter and K-escape) and the effect of charge diffusion between pixels are problematic. By organising the detector in several different layers, the count rate can be further reduced. However this alone does not limit the count rates to the required level, since the high stopping power of the material becomes a disadvantage in the layered approach: a simple absorption calculation for 300 µm pixel pitch shows that the required layer thickness of below 10 Mcps/pixel for the top layers in the direct beam is significantly below 100 µm. In a horizontal multi-layer detector, such thin layers are very difficult to manufacture due to the brittleness of Cd[Zn]Te. In a vertical configuration (also called edge-on illumination (Ludqvist et al 2001 IEEE Trans. Nucl. Sci. 48 1530-6, Roessl et al 2008 IEEE NSS-MIC-RTSD 2008, Conf. Rec. Talk NM2-3)), bonding of the readout electronics (with pixel pitches below 100 µm) is not straightforward although it has already been done successfully (Pellegrini et al 2004 IEEE NSS MIC 2004 pp 2104-9). Obviously, for the top detector layers, materials with lower stopping power would be advantageous

  11. CT findings as confirmatory criteria of brain death

    International Nuclear Information System (INIS)

    Shiogai, Toshiyuki; Takeuchi, Kazuo

    1983-01-01

    The absence of cerebral circulation and electrocerebral silence have served as an accurate index of irreversible brain death. It is proposed that computed tomography (CT) findings be evaluated as confirmatory criteria of brain death. To this end, CT evaluation of 14 patients satisfying the conventional criteria of brain death was performed. A CT finding of severe compression or dissappearance of the ventricular system, or so called ''brain tamponade'', was seen in 7 (50 %) of the 14 patients. Enhanced contrast CT, especially dynamic CT, usually distinctly reveals the cerebral vessels whenever the cerebral blood flow is preserved; conversely, the lack of enhanced brain structures, even comparing attenuation values, indicates the absence of cerebral blood flow. In 7 (70 %) of 10 patients, however, there was enhanced contrast of vascular brain structures, especially the circle of Willis, major cerebral arteries, choroid plexuses, and venous sinuses. It is suggested that this result is due to the improvement of demonstrability by CT. The usefulness of CT in the confirmation of brain death lies in visualization of the pathological changes associated with a dead brain, such as ''brain tamponade'', and the lack of enhanced contrast indicating the absence of cerebral blood flow. The latter point is still problematic as angiography revealed an extremely low cerebral blood flow in a few cases of ''dead brain'' patients. It is recommended that cerebral blood flow in brain death be evaluated by dynamic CT scanning and correlated with other methods of cerebral blood flow determination (e.g., intravenous digital subtraction angiography). (Author)

  12. CT findings as confirmatory criteria of brain death

    Energy Technology Data Exchange (ETDEWEB)

    Shiogai, Toshiyuki; Takeuchi, Kazuo (Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine)

    1983-12-01

    The absence of cerebral circulation and electrocerebral silence have served as an accurate index of irreversible brain death. It is proposed that computed tomography (CT) findings be evaluated as confirmatory criteria of brain death. To this end, CT evaluation of 14 patients satisfying the conventional criteria of brain death was performed. A CT finding of severe compression or dissappearance of the ventricular system, or so called ''brain tamponade'', was seen in 7 (50 %) of the 14 patients. Enhanced contrast CT, especially dynamic CT, usually distinctly reveals the cerebral vessels whenever the cerebral blood flow is preserved; conversely, the lack of enhanced brain structures, even comparing attenuation values, indicates the absence of cerebral blood flow. In 7 (70 %) of 10 patients, however, there was enhanced contrast of vascular brain structures, especially the circle of Willis, major cerebral arteries, choroid plexuses, and venous sinuses. It is suggested that this result is due to the improvement of demonstrability by CT. The usefulness of CT in the confirmation of brain death lies in visualization of the pathological changes associated with a dead brain, such as ''brain tamponade'', and the lack of enhanced contrast indicating the absence of cerebral blood flow. The latter point is still problematic as angiography revealed an extremely low cerebral blood flow in a few cases of ''dead brain'' patients. It is recommended that cerebral blood flow in brain death be evaluated by dynamic CT scanning and correlated with other methods of cerebral blood flow determination (e.g., intravenous digital subtraction angiography).

  13. CT findings in mucopolysaccharidoses

    International Nuclear Information System (INIS)

    Tsuchida, Tomio; Nemoto, Shigeru; Fujiwara, Kazue; Hayakawa, Isao; Nihei, Kenji.

    1981-01-01

    The CT findings for four patients with mucopolysaccharidosis were analyzed using a Delta scan-25 (Ohio Nuclear). In three cases of Hunter's syndrome (MPS IIA 13-year-old male, MPS IIB 12-year-old male, and 25-year-old male), a dilatation of the cortical sulci was observed. Moderate dilatations were also seen in the basal cistern, the quadrigeminal cistern, and the ambient cistern. In one case of Hunter's syndrome, a low-density area was observed in the bilateral tharamic regions. An irregular low-density area was also seen in the white matter in some cases. PVL was not apparent in any case. Marked ventricular dilations were observed in cases with mental retardation, for example, in one case of Hurler's syndrome (8-year-old male) and one case of MPS IIA. The circulation and absorbtion of CSF in cortical snbarachnoid spaces were supposed to be moderately retarded by metrizamide CT cisternography. (author)

  14. Helical CT imaging of clinically suspected appendicitis: Correlation of CT and histological findings

    International Nuclear Information System (INIS)

    Wong, S.K.; Chan, L.P.; Yeo, A.

    2002-01-01

    PURPOSE: The diagnosis of appendicitis is traditionally made on the basis of clinical findings supported by laboratory results. The aim of our study was to determine the accuracy and feasibility of using a relatively new technique of computed tomography (CT) using only colonic contrast medium. MATERIALS AND METHODS: A total of 50 patients clinically diagnosed as having appendicitis were prospectively examined before surgery with thin-collimation helical CT from the L3 level to the acetabular roof with only rectally administered colon contrast medium. The hard copy CT images were reviewed jointly by two radiologists and a consensus was reached for each patient. The results were then compared with the surgical and histological findings at appendicectomy. RESULTS: There were 35 true-positives, one false-positive, 12 true-negatives and two false-negatives for CT. This yielded an accuracy of 94%, sensitivity of 95%, specificity of 92%, positive predictive value of 97% and negative predictive value of 86%. The appendix was identified in 45 patients (90%) and obscured by an inflammatory mass in the remaining five. An alternative diagnosis was found in 10 of 12 normal CT examinations (83%). CONCLUSION: Helical CT with rectal contrast medium is a quick, well tolerated and accurate test to diagnose appendicitis. It can offer alternative, possibly non-surgical diagnosis in patients who would otherwise have undergone laparotomy. Wong, S.K. et al. (2002)

  15. Clinical menifestations and CT findings of lacunar infarction

    International Nuclear Information System (INIS)

    Shimada, Tsutomu; Kaneko, Mitsuo; Tanaka, Keisei; Sato, Kengo; Yamamoto, Toshiki

    1983-01-01

    Since the introduction of the CT scanner, the present authors have experienced 111 cases of lacunar infarction which were diagnosed on the basis of clinical manifestations and/or CT findings, being 35 % of total 318 cases of acute cerebral infarction in our series. The clinical features and their correlation with the CT findings were studied in the cases of lacunar infarction. The results were as follows. 1) Seventy-four per cent of the patients were hypertensive. 2) Fifty per cent of the patients had only motor deficit. 3) The patients who revealed small deep infarctions in the posterior two-thirds of the posterior limb of the internal capsule on CT scan had more marked motor impariment with more involvement of the upper extremity than the lower extremity. 4) The recovery of the motor deficit was generally good, but unsatisfactory when the patient had a larger lesion than 10 mm in diameter. (author)

  16. CT findings complicating percutaneous nephrostomy, lithotomy and lithotripsy

    Energy Technology Data Exchange (ETDEWEB)

    Kanazawa, Susumu; Douke, Tetsuya; Araki, Toru; Takamoto, Hitoshi; Yoshida, Mitsuhiro; Hata, Kazuhiro (Center for Adult Diseases, Kurashiki, Okayama (Japan)); Yasui, Kotaro

    1990-09-01

    Reviews of the CT scans of percutaneous nephrostomy, lithotomy and lithotripsy disclosed 14 out of 78 cases (17.9%) with evidence of complications. Renal and perirenal hematomas were detected in five cases and the other five cases showed collections of contrast material in the retroperitoneum except for the anterior pararenal space. CT demonstrated clearly the anatomic distribution and extent of renal hemorrhage and extravasation of contrast material. Three cases of pleural effusion on CT were accompanied by blood or contrast material collections in the posterior pararenal space. No patients required immediate surgery and CT findings helped the choice of conservative therapies. (author).

  17. CT findings of central nervous system in congenital syphilis infant

    International Nuclear Information System (INIS)

    Yang Cheng; Yang Xinghui; Wang Man

    2005-01-01

    Objective: To investigate the CT features of the central nervous system in congenital syphilis infant. Methods: CT findings of central nervous system in 11 infants with clinically proved congenital syphilis were analyzed retrospectively. Results: CT findings in 10 syphilis neonates were diffuse hypodense lesions in the white matter, with subarachnoid and intra-encephalic hemorrhage in 3 and 1 cases, respectively. One 2-month-old syphilis infant case and 5 cases of follow-up after 45 days to 6 months of treatment demonstrated bilateral widened sulci and cistern with enlarged ventricles in 3 of them. Conclusion: CT findings of the central nervous system in congenital syphilis infant are similar to those of hypoxic-ischemic encephalopathy in neonates, and extra-encephalic hydrocephalus or brain hypogenesis ensues later on. (authors)

  18. The significance of multi-slice helical CT multiplanar reconstruction in the diagnoses of laryngeal carcinoma

    International Nuclear Information System (INIS)

    Li Lin; Luo Dehong; Zhou Chunwu; Zhao Xinming; Jiang Liming; Huang Yao; Jiang Lingxia; Li Jing; Wu Ning

    2006-01-01

    Objective: To evaluate the significance of multi-slice helical CT with multiplanar reconstruction in laryngeal carcinoma. Methods: Thirty-five patients with laryngeal carcinoma were studied by helical CT, MPR were subsequently done. The lesion extent of the axial image findings, MPR findings and the combined image findings were compared with the pathological results respectively. The data were statistically analyzed. Results: In the evaluation of the anterior commissure, the axial image findings, MPR findings and the combined image findings were 82.9%, 68.6% and 91.4% in accuracy respectively, the results were statistically different (P 0.05). The combined images were superior to the axial images and the MPR images in sensitivity, specificity and accuracy of the lesion extent. Conclusion: The axial images could show the shape, size, extension of the tumor and the lymphadenopathy, MPR images displayed the shape, size and extension roundly and directly, they were the supplement for the axial images. Axial images combined with MPR could improve the accuracy in the diagnoses of laryngeal carcinoma. (authors)

  19. CASE SERIES Multi-detector computer tomography venography ...

    African Journals Online (AJOL)

    in the curved coronal plane with particular reference to the course of the common and external iliac veins through the pelvis. Axial venous. Aim. To evaluate the role of multi-detector computer tomography venography (MDCTV), compared with conventional venography, as a diagnostic tool in the management of patients with ...

  20. Upper limits of the photon fluence rate on CT detectors: Case study on a commercial scanner

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    Persson, Mats, E-mail: mats.persson@mi.physics.kth.se; Bornefalk, Hans; Danielsson, Mats [Department of Physics, Royal Institute of Technology, Stockholm SE-10691 (Sweden); Bujila, Robert; Nowik, Patrik; Andersson, Henrik [Unit of X-ray Physics, Section of Imaging Physics Solna, Department of Medical Physics, Karolinska University Hospital, Stockholm SE-17176 (Sweden); Kull, Love [Medical Radiation Physics, Sunderby Hospital, Luleå SE-97180 (Sweden); Andersson, Jonas [Department of Radiation Sciences, Radiation Physics, Umeå University, Umeå SE-90185 (Sweden)

    2016-07-15

    Purpose: The highest photon fluence rate that a computed tomography (CT) detector must be able to measure is an important parameter. The authors calculate the maximum transmitted fluence rate in a commercial CT scanner as a function of patient size for standard head, chest, and abdomen protocols. Methods: The authors scanned an anthropomorphic phantom (Kyoto Kagaku PBU-60) with the reference CT protocols provided by AAPM on a GE LightSpeed VCT scanner and noted the tube current applied with the tube current modulation (TCM) system. By rescaling this tube current using published measurements on the tube current modulation of a GE scanner [N. Keat, “CT scanner automatic exposure control systems,” MHRA Evaluation Report 05016, ImPACT, London, UK, 2005], the authors could estimate the tube current that these protocols would have resulted in for other patient sizes. An ECG gated chest protocol was also simulated. Using measured dose rate profiles along the bowtie filters, the authors simulated imaging of anonymized patient images with a range of sizes on a GE VCT scanner and calculated the maximum transmitted fluence rate. In addition, the 99th and the 95th percentiles of the transmitted fluence rate distribution behind the patient are calculated and the effect of omitting projection lines passing just below the skin line is investigated. Results: The highest transmitted fluence rates on the detector for the AAPM reference protocols with centered patients are found for head images and for intermediate-sized chest images, both with a maximum of 3.4 ⋅ 10{sup 8} mm{sup −2} s{sup −1}, at 949 mm distance from the source. Miscentering the head by 50 mm downward increases the maximum transmitted fluence rate to 5.7 ⋅ 10{sup 8} mm{sup −2} s{sup −1}. The ECG gated chest protocol gives fluence rates up to 2.3 ⋅ 10{sup 8} − 3.6 ⋅ 10{sup 8} mm{sup −2} s{sup −1} depending on miscentering. Conclusions: The fluence rate on a CT detector reaches 3 ⋅ 10{sup 8

  1. Thin-section chest CT findings in systemic lupus erythematosus with antiphospholipid syndrome: A comparison with systemic lupus erythematosus without antiphospholipid syndrome

    International Nuclear Information System (INIS)

    Oki, Hodaka; Aoki, Takatoshi; Saito, Kazuyoshi; Yamashita, Yoshiko; Hanamiya, Mai; Hayashida, Yoshiko; Tanaka, Yoshiya; Korogi, Yukunori

    2012-01-01

    Purpose: To assess thin-section chest CT findings in systemic lupus erythematosus (SLE) with antiphospholipid syndrome (APS), in comparison with SLE without APS. Materials and methods: We retrospectively reviewed the medical records and thin-section CT findings of 17 consecutive patients with an established diagnosis of SLE with APS, comparing with 37 consecutive SLE patients without APS, between 2004 and 2008, and patients who had other autoimmune disease, such as Sjögren syndrome, were excluded. No significant differences were seen between the two groups in age, gender, smoking habits, or history of steroid pulse and biological therapy. CT images of 2 mm thickness obtained with a 16- or 64-detector row CT were retrospectively evaluated by two radiologists in consensus on ultra high-resolution gray-scale monitors. Results: The frequency of thin-section CT abnormalities was higher in SLE with APS group (82%) than in SLE without APS group (43%). Ground-glass opacity (59%), architectural distortion (47%), reticulation (41%), enlarged peripheral pulmonary artery (29%), and mosaic attenuation (29%) were significantly more common in the SLE with APS group than in the SLE without APS group (Fisher's exact test, p < 0.01). Conclusion: SLE patients with APS have increased prevalence of thin-section chest CT abnormalities than those without APS.

  2. CT findings of perihepatic tuberculous abscess

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    Ryu, Jeong Ah; Lee, Jong Tae; Chung, Jae Joon; Park, Su Mi; Kim, Myeong Jin; Yoo, Hyung Sik [Yonsei Univ. College of Medicine, Research Institute of Radiological Science, Yonsei Univ., Seoul (Korea, Republic of)

    1999-12-01

    To evaluate the CT findings of perihepatic tuberculous abscesses. The CT scans of 11 patients (6 females and 5 males) with 14 pathologically proven perihepatic tuberculous abscess were retrospectively evaluated in terms of the morphological characteristics of the abscesses and changes in other abdominal organs and at other sites. A total of 14 absceses were noted in 11 patients. Six (43%) were in the right subphrenic space, three (21%) in the right perihepatic space, three (21%) in the left subphrenic space, and two (14%) in the left perihepatic space. The right side was predominant. The abscesses ranged in size from 1 to 10 (mean, 5) cm in diameter, with a wall thickness of 2-7 (mean, 3) mm. Of the 14 abscesses, 13 were oval, and one spherical. CT findings were as follows : a smooth abscess margin with even wall thickness in seven of the eleven patients (64%); calcification of the wall in two (18%); internal septa in seven (64%); localized fluid collection in nine (82%); lymphadenopathy in five (45%); and peritoneal enhancement in seven (64%). Lesions suggesting tuberculous infection coexisted at other sites in eight patients. These included the lung in six patients (55%), the neck in three (27%), an axilla in two (18%), the liver in two (18%), the spleen in one (9%), and the gastroin-testinal tract in one (9%). CT scanning is useful for establishing the diagnosis of perihepatic tuberculous abscesses by evaluating the morphological characteristics of the mass and by observing changes in other abdominal organs and at other sites.

  3. CT findings of perihepatic tuberculous abscess

    International Nuclear Information System (INIS)

    Ryu, Jeong Ah; Lee, Jong Tae; Chung, Jae Joon; Park, Su Mi; Kim, Myeong Jin; Yoo, Hyung Sik

    1999-01-01

    To evaluate the CT findings of perihepatic tuberculous abscesses. The CT scans of 11 patients (6 females and 5 males) with 14 pathologically proven perihepatic tuberculous abscess were retrospectively evaluated in terms of the morphological characteristics of the abscesses and changes in other abdominal organs and at other sites. A total of 14 absceses were noted in 11 patients. Six (43%) were in the right subphrenic space, three (21%) in the right perihepatic space, three (21%) in the left subphrenic space, and two (14%) in the left perihepatic space. The right side was predominant. The abscesses ranged in size from 1 to 10 (mean, 5) cm in diameter, with a wall thickness of 2-7 (mean, 3) mm. Of the 14 abscesses, 13 were oval, and one spherical. CT findings were as follows : a smooth abscess margin with even wall thickness in seven of the eleven patients (64%); calcification of the wall in two (18%); internal septa in seven (64%); localized fluid collection in nine (82%); lymphadenopathy in five (45%); and peritoneal enhancement in seven (64%). Lesions suggesting tuberculous infection coexisted at other sites in eight patients. These included the lung in six patients (55%), the neck in three (27%), an axilla in two (18%), the liver in two (18%), the spleen in one (9%), and the gastroin-testinal tract in one (9%). CT scanning is useful for establishing the diagnosis of perihepatic tuberculous abscesses by evaluating the morphological characteristics of the mass and by observing changes in other abdominal organs and at other sites

  4. Nonconcordance between Clinical and Head CT Findings: The Specter of Overdiagnosis

    Directory of Open Access Journals (Sweden)

    Kelli N. O'Laughlin

    2013-01-01

    Full Text Available Background. It is unclear whether history and physical examination findings can predict abnormalities on head computed tomography (CT believed to indicate increased risk of lumbar-puncture- (LP- induced brain herniation. The objectives of this study were to (1 identify head CT findings felt to be associated with increased risk of brain herniation and (2 to assess the ability of history and physical examination to predict those findings. Methods. Using a modified Delphi survey technique, an expert panel defined CT abnormalities felt to predict increased risk of LP-induced brain herniation. Presence of such findings on CT was compared with history and physical examination (H&P variables in 47 patients. Results. No H&P variable predicted “high-risk” CT; combining H&P variables to improve sensitivity led to extremely low specificity and still failed to identify all patients with high-risk CT. Conclusions. “High-risk” CT is not uncommon in patients with clinical characteristics known to predict an absence of actual risk from LP, and thus it may not be clinically relevant. “Overdiagnosis” will be increasingly problematic as technological advances identify increasingly subtle deviations from “normal.”

  5. Thoracic chordoma: CT and MR findings

    International Nuclear Information System (INIS)

    Cha, Yoo Mi; Hwang, Hee Young; Kim, Sang Joon; Chung, Hyo Sun; Han, Heon

    1993-01-01

    Chordoma arising from the notochordal remnants is a rare primary bone tumor in the cervicosacral region and is even more unusual in the thoracic region. The authors experienced a case of thoracic chordoma and reports its CT and MR findings

  6. Computed tomography (CT) findings in 88 neurofibromatosis 1 (NF1) patients: Prevalence rates and correlations of thoracic findings

    International Nuclear Information System (INIS)

    Ueda, Ken; Honda, Osamu; Satoh, Yukihisa; Kawai, Misa; Gyobu, Tomoko; Kanazawa, Toru; Hidaka, Shojiro; Yanagawa, Masahiro; Sumikawa, Hiromitsu; Tomiyama, Noriyuki

    2015-01-01

    Highlights: • Various thoracic CT findings, including cysts, mediastinal masses, etc. were found. • Cysts show upper and peripheral dominant distribution. • The number, size, and distribution of the pulmonary cysts in NF-1 revealed significant correlation. • It is suspected that thoracic CT findings in NF-1 occur independently. - Abstract: Purpose: To evaluate the prevalence rates and the correlations of thoracic computed tomography (CT) findings of neurofibromatosis 1 (NF1) in 88 patients. Materials and methods: Chest CT images of 88 NF1 patients were independently reviewed by three observers, and the CT findings were evaluated. If abnormal findings were present, their number, size, and distribution were recorded. The prevalence rate of each CT finding was calculated, and the correlations between CT findings were analyzed. Results: Of the 88 cases, 13 were positive for cysts, 16 for emphysema, 8 for nodules, 8 for GGNs (ground glass nodules), 13 for mediastinal masses, 20 for scoliosis, 44 for subcutaneous nodules, and 34 for skin nodules. Cysts showed upper and peripheral dominant distributions. Regarding 13 mediastinal masses, 2 were diagnosed as malignant peripheral nerve sheath tumors (MPNSTs), 1 was diagnosed as primary lung cancer, 2 were diagnosed as lateral meningocele, 3 were diagnosed as neurofibromas, and the remaining 7 were considered neurofibromas. There was a significant correlation between the prevalence of subcutaneous nodules and that of skin nodules. Significant positive correlations were also seen between size and number, size and rate of central distribution, and number and rate of central distribution of cysts. Conclusion: Various CT findings were found in NF-1 patients, and the prevalence rates of subcutaneous and skin nodules were higher than other findings. Though the prevalence rates of subcutaneous nodules and skin nodules were significantly correlated, the other CT findings in NF-1 occurred independently. The number, size, and

  7. Computed tomography (CT) findings in 88 neurofibromatosis 1 (NF1) patients: Prevalence rates and correlations of thoracic findings

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Ken, E-mail: k-ueda@radiol.med.osaka-u.ac.jp [Department of Radiology, Osaka University Graduate School of Medicine (Japan); Honda, Osamu [Department of Radiology, Osaka University Graduate School of Medicine (Japan); Satoh, Yukihisa [Department of Diagnostic Radiology, Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan); Kawai, Misa; Gyobu, Tomoko; Kanazawa, Toru; Hidaka, Shojiro; Yanagawa, Masahiro [Department of Radiology, Osaka University Graduate School of Medicine (Japan); Sumikawa, Hiromitsu [Department of Diagnostic Radiology, Osaka Rosai Hospital (Japan); Tomiyama, Noriyuki [Department of Radiology, Osaka University Graduate School of Medicine (Japan)

    2015-06-15

    Highlights: • Various thoracic CT findings, including cysts, mediastinal masses, etc. were found. • Cysts show upper and peripheral dominant distribution. • The number, size, and distribution of the pulmonary cysts in NF-1 revealed significant correlation. • It is suspected that thoracic CT findings in NF-1 occur independently. - Abstract: Purpose: To evaluate the prevalence rates and the correlations of thoracic computed tomography (CT) findings of neurofibromatosis 1 (NF1) in 88 patients. Materials and methods: Chest CT images of 88 NF1 patients were independently reviewed by three observers, and the CT findings were evaluated. If abnormal findings were present, their number, size, and distribution were recorded. The prevalence rate of each CT finding was calculated, and the correlations between CT findings were analyzed. Results: Of the 88 cases, 13 were positive for cysts, 16 for emphysema, 8 for nodules, 8 for GGNs (ground glass nodules), 13 for mediastinal masses, 20 for scoliosis, 44 for subcutaneous nodules, and 34 for skin nodules. Cysts showed upper and peripheral dominant distributions. Regarding 13 mediastinal masses, 2 were diagnosed as malignant peripheral nerve sheath tumors (MPNSTs), 1 was diagnosed as primary lung cancer, 2 were diagnosed as lateral meningocele, 3 were diagnosed as neurofibromas, and the remaining 7 were considered neurofibromas. There was a significant correlation between the prevalence of subcutaneous nodules and that of skin nodules. Significant positive correlations were also seen between size and number, size and rate of central distribution, and number and rate of central distribution of cysts. Conclusion: Various CT findings were found in NF-1 patients, and the prevalence rates of subcutaneous and skin nodules were higher than other findings. Though the prevalence rates of subcutaneous nodules and skin nodules were significantly correlated, the other CT findings in NF-1 occurred independently. The number, size, and

  8. Hypoxic ischemic encephalopathy in children : CT findings related to prognosis

    International Nuclear Information System (INIS)

    Cho, Jae Min; Il, Yim Byung; Kim, Ok Hwa; Kang, Doo Kyoung; Suh, Jung Ho

    1997-01-01

    To evaluate prognosis-related CT findings in hypoxic ischemic encephalopathy. For the purpose of prognosis, 28 children with a clinical history and CT findings suggestive of hypoxic ischemic encephalopathy (HIE) were restrospectively reviewed. The diagnostic criteria for HIE, as seen on CT scanning, were as follows : 1, ventricular collapse;2, effacement of cortical sulci;3, prominent enhancement of cortical vessels;4, poor differentiation of gray and white matter;5, reversal sign;6, obliteration of perimesencephalic cistern;7, high density on tentorial edge, as seen on precontrast scans;and 8, low density in thalamus, brain stem and basal ganglia. On the basis of clinical outcome, we divided the patients into three groups, as follows:group I(good prognosis);group II(neurologic sequelae), and group III(vegetative state or expire), and among these, compared CT findings. There were thirteen patients in group I, six in group II, and nine in group III. Ventricular collapse, effacement of cortical sulci, and prominent enhancement of cortical vessels were noted in all groups, whereas poor differentiation of gray and white matter, reversal sign, obliteration of perimesencephalic cistern, high density on tentorial edge, on precontrast scan, and low density in brain stem and basal ganglia were observed only in groups II and III. CT findings showed distinct differences between groups in whom prognosis was good, and in whom it was poor. An awareness of poor prognostic CT findings may be clinically helpful in the evaluation of patients with hypoxic ischemic encephalopathy

  9. CT findings of cerebral fat embolism

    International Nuclear Information System (INIS)

    Mashiyama, Shoji; Kawakami, Kiyoshi; Ohtsuki, Taisuke; Ishibashi, Takao.

    1986-01-01

    A case of cerebral fat embolism following multiple bone fractures is presented. A 27-year-old patient was admitted to our clinic 50 minutes after a traffic accident. He was somnolent on admission, but his consciousness level was gradually raised and respiratory symptoms (dyspnea, bloody sputum) appeared with petechiae of his conjunctiva and chest. We diagnosed cerebral fat embolism. On CT scan we found multiple high-density areas, which gradually turned into multiple low-density areas. Subsequent cerebral atrophy and subdural effusion developed one month after the injury. This patient showed a typical clinical course and CT findings of cerebral fat embolism. (author)

  10. CT and MR findings in retinoblastoma : correlation with histopathologic examination

    International Nuclear Information System (INIS)

    Park, Son Won; Han, Moon Hee; Chi, Je G.; Yu, Young Suk; Kim, Yeon Mee; Chung, Jin Haeng; Yu, In Kyu; Chang, Kee Hyun; Yeon, Kyung Mo

    1997-01-01

    To evaluate histopathologic correlation of the component of the lesion on CT and MR of retinoblastomas. Gross pathologic findings of 24 enucleated eyeballs in 24 patients with retinoblastomas were compared with preoperative CT (n=19) and MR (n=5) findings. In eight eyeballs, in which there were findings other than mass, histopathologic findings were reviewed and correlated with image findings. Retinal detachment and subretinal hemorrhage which were not detected on CT were demonstrated in two of eight eyeballs on histopathologic examination. In one eyeball, retinal detachment and subretinal effusion were detected on both CT and in a pathologic specimen. In two eyeballs with peripheral heterogeneous MR enhancement of the masses, tumor necrosis and calcification were demonstrated in the central non-emhancing portion of the mass, In two eveballs, linear soft tissue along the retina apart from the main mass were revealed as tumor spread along the retinal surface. In one patient, retinal thickening on MR was presumed to be an MR artifact and no lesion was found in the gross specimen. On CT, retinal detachment and subretinal hemorrhage associated with retinoblastoma can mimic mass, and tumor spread along the retinal surface can be seen as a linear retinal lesion. On MR, tumor necrosis and calcification can be a cause of heterogeneous enhancement

  11. A study on CT findings and electroencephalographic findings in severely handicapped children

    International Nuclear Information System (INIS)

    Nakashima, Masao; Nishimura, Masaaki; Kachi, Shozo; Sugimoto, Kimiyuki; Saito, Msahiko; Yamada, Shigeaki; Kameyama, Yoshio; Tanaka, Minoru; Hiraizumi, Yasuhisa.

    1987-01-01

    Sleep electroencephalographic (EEG) and computed tomographic (CT) features were examined in 40 institutionalized severely handicapped persons. Cranial CT appearance fell into five major types: (I) no abnormal findings (n=2), (II) generalized brain atrophy (n=16), (III) diffuse parenchymal disturbance (n=10), (IV) brain malformation (n=4), and (V) localized brain disturbance (n=8). In the I group, one person had normal EEG findings as well, but another person had the presence of focal spikes without spindles on EEG. Five of the II group had no abnormal EEG findings; ten had abnormality in basic waves and/or localized paroxysmal waves; and one had generalized spike-and-slow wave complex. All persons in the III group had flattening or disappearance of spindle waves. In the IV group, two persons with cerebral malformation and one with linear nevus sebaceous syndrome in association with hypoplasia of the cerebral hemisphere had abnormality in basic waves and localized paroxysmal waves. In the remaining one person with deficit of vermis cerebelli, there was no EEG abnormality. Among the last group of persons, there was no EEG abnormality corresponding to CT features. (Namekawa, K)

  12. A preliminary study on the CT finding in SARS following hospital discharge

    International Nuclear Information System (INIS)

    Zhang Lieguang; Liu Jinxing; Chen Bihua; Jiang Songfeng

    2004-01-01

    Objective: To study the CT finding of chest in patient with SARS following hospital discharge. Methods: Thirty-six patients (11 men, 25 women; age range, 20-73 years; mean age, 39 years) with confirmed SARS underwent follow-up spiral CT. The scans were obtained on average 187 days (range from 152 days to 225 days) after onset of symptoms. Patients were assigned to group 1 (with heavy SARS, n=19) and group 2 (with common SARS, n=17) for analysis. The chest X-ray films of the 36 patients in fastigium of film were retrospectively reviewed. Results: 58.33% (21 of 36) cases are normal on the CT of thorax. In group 1 42.11% (8 of 19) cases and in group 2 76.47%(13 of 17) cases. In group 1: 31.58%(6 of 19) cases present diffuse ground-glass opacification, 21.05% (4 of 19) cases present multi-patch ground-glass opacification, 5.26% (1 of 19) cases present local ground-glass opacification in single lobar, 31.58% (6 of 19) cases present intralobular interstitial thickening and/or interlobular septal thickening, 5.26% (1 of 19) present subpleural lines, 5.26% (1 of 19) present honeycombing, 5.26% (1 of 19) cases present bullae; In group 2: 11.76% (2 of 17) cases present local ground-glass opacification, 11.76%(2 of 17) cases present intralobular interstitial thickening and/or interlobular septal thickening, 5.88%(1 of 17) cases present organized pneumonia. In group 1, 73.68% (14/19) cases in fastigium of film present large areas of lung consolidation and diffuse ground-glass opacification. Conclusion: Most of the healing SARS cases after certain time are normal on the CT finding of thorax. Part of them remain manifests such as ground-glass opacification, intralobular interstitial thickening and/or interlobular septal thickening, subpleural lines, honeycombing, traction bronchiectasis, organized pneumonia and bullae. They relate to severeness of the lesion of the lung in fastigium of film. Such finding can last for long time and probably fibrosis can be developed. (authors)

  13. Sequential analysis of CT findings in herpes simplex encephalitis

    International Nuclear Information System (INIS)

    Kawamura, Mitsuru; Tokumaru, Yukio; Ito, Naoki; Yamada, Tatsuo; Hirayama, Keizo

    1982-01-01

    CT findings of six patients with serologically confirmed herpes simplex encephalitis were analyzed sequentially. The initial change in CT scan in 3 cases was generalized cerebral edema instead of low density areas in the anterior temporal lobes, which have generally been known as the initial findings. Then, bilateral (5 cases) or unilateral (1 case) island-shaped low absorption areas in the insular cortex and the claustrum appeared within 10 days of onset in all 6 cases. These findings, especially the latter, seem to be characteristic of the acute stage and useful in the early diagnosis of herpes simplex encephalitis. The low density areas, then, spread to the temporal lobes, rectal and cingulate gyri in the subacute stage (3 cases) and finally to the frontal and occipital lobes in the chronic stage (2 cases). In the basal ganglia, thalamus, brain stem and cerebellum, however, there were no low density areas. In 2 cases there was no progression of low density areas beyond those of the acute stage. In one case there were high density areas in the temporal lobes and parapontine cisterns bilaterally. This could correspond to the pathological findings in herpes simplex encephalitis. The improvement of CT findings (or arrest at the early stage) was noted in 2 cases in which the clinical state also improved. This might well be the effect of adenine arabinoside. The one case treated with cytosine arabinoside had extensive low density areas in CT and finally died. The importance of CT in the evaluation of adenine arabinoside therapy was stressed. (author)

  14. The clinical application studies of CT spinal angiography with 64-detector row spiral CT in diagnosing spinal vascular malformations

    International Nuclear Information System (INIS)

    Gao Sijia; Zhang Mengwei; Liu Xiping; Zh Yushen; Liu Jinghong; Wang Zhonghui; Zang Peizhuo; Shi Qiang; Wang Qiang; Liang Chuansheng; Xu Ke

    2009-01-01

    Background and purpose: To explore the value of CT spinal angiography with 64-detector row spiral CT in diagnosing spinal vascular malformations. Methods: Seventeen patients with initial MR and clinical findings suggestive of spinal vascular diseases underwent CT spinal angiography. Among these, 14 patients took DSA examination within 1 week after CT scan, 7 patients underwent surgical treatment, and 6 patients underwent vascular intervention embolotheraphy. CT protocol: TOSHIBA Aquilion 64 Slice CT scanner, 0.5 mm thickness, 0.5 s/r, 120 kV and 350 mA, positioned at the aortic arch level, and applied with 'sure start' technique with CT threshold of 180 Hu. Contrast agent Iohexol (370 mg I/ml) was injected at 6 ml/s velocity with total volume of 80 ml. The post-processing procedures included MPR, CPR, MIP, VR, etc. Among the 17 patients, four patients underwent fast dynamic contrast-enhanced 3D MR angiography imaging. CT spinal angiography and three-dimensional contrast-enhanced MR angiography (3D CE-MRA) images were compared and evaluated with DSA and operation results based on disease type, lesion range, feeding arteries, fistulas, draining veins of vascular malformation by three experienced neuroradiologists independently, using double blind method. The data were analyzed using SPSS analytic software with χ 2 -test. We compared the results with DSA and operation results. Results: The statistical analysis of the diagnostic results by the three experienced neuroradiologists had no statistical difference (P > 0.05). All of the 17 patients showed clearly the abnormality of spinal cord vessels and the range of lesions by CT spinal angiography. Among them, one patient was diagnosed as arteriovenous fistulas (AVF) by MRI and CT spinal angiography, which was verified by surgical operation. DSA of the same patient, however, did not visualize the lesion. One case was diagnosed as AVM complicated with AVF by DSA, but CT spinal angiography could only show AVM not AVF. The

  15. The clinical application studies of CT spinal angiography with 64-detector row spiral CT in diagnosing spinal vascular malformations

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    Gao Sijia [Department of Radiology, No. 1 Affiliated Hospital of China Medical University, Shenyang 110001 (China)], E-mail: scarlettgao@126.com; Zhang Mengwei; Liu Xiping; Zh Yushen; Liu Jinghong; Wang Zhonghui [Department of Radiology, No. 1 Affiliated Hospital of China Medical University, Shenyang 110001 (China); Zang Peizhuo [Department of Neurosurgery, No. 1 Affiliated Hospital of China Medical University, Shenyang 110001 (China); Shi Qiang; Wang Qiang [Department of Radiology, No. 1 Affiliated Hospital of China Medical University, Shenyang 110001 (China); Liang Chuansheng [Department of Neurosurgery, No. 1 Affiliated Hospital of China Medical University, Shenyang 110001 (China); Xu Ke [Department of Radiology, No. 1 Affiliated Hospital of China Medical University, Shenyang 110001 (China)

    2009-07-15

    Background and purpose: To explore the value of CT spinal angiography with 64-detector row spiral CT in diagnosing spinal vascular malformations. Methods: Seventeen patients with initial MR and clinical findings suggestive of spinal vascular diseases underwent CT spinal angiography. Among these, 14 patients took DSA examination within 1 week after CT scan, 7 patients underwent surgical treatment, and 6 patients underwent vascular intervention embolotheraphy. CT protocol: TOSHIBA Aquilion 64 Slice CT scanner, 0.5 mm thickness, 0.5 s/r, 120 kV and 350 mA, positioned at the aortic arch level, and applied with 'sure start' technique with CT threshold of 180 Hu. Contrast agent Iohexol (370 mg I/ml) was injected at 6 ml/s velocity with total volume of 80 ml. The post-processing procedures included MPR, CPR, MIP, VR, etc. Among the 17 patients, four patients underwent fast dynamic contrast-enhanced 3D MR angiography imaging. CT spinal angiography and three-dimensional contrast-enhanced MR angiography (3D CE-MRA) images were compared and evaluated with DSA and operation results based on disease type, lesion range, feeding arteries, fistulas, draining veins of vascular malformation by three experienced neuroradiologists independently, using double blind method. The data were analyzed using SPSS analytic software with {chi}{sup 2}-test. We compared the results with DSA and operation results. Results: The statistical analysis of the diagnostic results by the three experienced neuroradiologists had no statistical difference (P > 0.05). All of the 17 patients showed clearly the abnormality of spinal cord vessels and the range of lesions by CT spinal angiography. Among them, one patient was diagnosed as arteriovenous fistulas (AVF) by MRI and CT spinal angiography, which was verified by surgical operation. DSA of the same patient, however, did not visualize the lesion. One case was diagnosed as AVM complicated with AVF by DSA, but CT spinal angiography could only show

  16. Clinically relevant incidental cardiovascular findings in CT examinations; Klinisch relevante kardiovaskulaere Zufallsbefunde bei CT-Untersuchungen

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    Voigt, P.; Fahnert, J.; Kahn, T.; Surov, A. [Universitaetsklinikum Leipzig, Klinik fuer Diagnostische und Interventionelle Radiologie, Leipzig (Germany); Schramm, D.; Bach, A.G. [Universitaetsklinikum Halle (Saale), Klinik fuer Radiologie, Halle (Germany)

    2017-04-15

    Incidental cardiovascular findings are a frequent phenomenon in computed tomography (CT) examinations. As the result of a dedicated PubMed search this article gives a systemic overview of the current literature on the most important incidental cardiovascular findings, their prevalence and clinical relevance. The majority of incidental cardiovascular findings are of only low clinical relevance; however, highly relevant incidental findings, such as aortic aneurysms, thromboses and thromboembolic events can also occasionally be found, especially in oncology patients. The scans from every CT examination should also be investigated for incidental findings as they can be of decisive importance for the further clinical management of patients, depending on their clinical relevance. (orig.) [German] Inzidentelle kardiovaskulaere Befunde sind ein haeufiges Phaenomen bei CT-Untersuchungen. Mit dieser Arbeit soll nach gezielter PubMed-Recherche ein systematischer Literaturueberblick ueber die wichtigsten kardiovaskulaeren Zufallsbefunde sowie deren Haeufigkeit und klinische Relevanz gegeben werden. Die Mehrzahl der inzidentellen kardiovaskulaeren Befunde sind klinisch nur von untergeordneter Bedeutung, allerdings werden immer wieder auch hochgradig relevante Zufallsbefunde wie beispielsweise Aortenaneurysmata oder - gerade bei onkologischen Patienten - Thrombosen und thrombembolische Ereignisse detektiert. Jede CT-Untersuchung sollte gezielt nach inzidentellen Befunden durchsucht werden, da diese je nach klinischer Relevanz von entscheidender Bedeutung fuer das weitere klinische Management des Patienten sein koennen. (orig.)

  17. CT findings associated with survival in chronic hypersensitivity pneumonitis

    International Nuclear Information System (INIS)

    Chung, Jonathan H.; Montner, Steven M.; Adegunsoye, Ayodeji; Vij, Rekha; Noth, Imre; Strek, Mary E.; Oldham, Justin M.; Husain, Aliya N.

    2017-01-01

    To identify CT findings in chronic hypersensitivity pneumonitis (cHP) associated with survival. Two thoracic radiologists assessed CT scans for specific imaging findings and patterns in 132 subjects with cHP. Survival analyses were performed. The majority of subjects had an inconsistent with usual interstitial pneumonitis pattern on CT (55.3%,73/132). Hypersensitivity pneumonitis (HP) diagnosis on CT was less common in those with fibrosis (66.1%, 74/112) than those without fibrosis (85%,17/20). Smoking was associated with a lower prevalence of HP on CT (p=0.04). CT features of pulmonary fibrosis, especially traction bronchiectasis (HR 8.34, 95% CI 1.98-35.21) and increased pulmonary artery (PA)/aorta ratio (HR 2.49, 95% CI 1.27-4.89) were associated with worse survival, while ground-glass opacity (HR 0.31, 95% CI 0.12-0.79) was associated with improved survival. Survival association with imaging was less pronounced after adjustment for gender, age and physiology score. A substantial proportion of cHP cases have a non-HP-like appearance. Ground-glass opacity, pulmonary fibrosis features and elevated PA/aorta ratio on CT likely reflect varying degrees of disease severity in cHP and may inform future clinical prediction models. (orig.)

  18. CT findings associated with survival in chronic hypersensitivity pneumonitis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Jonathan H.; Montner, Steven M. [University of Chicago Medical Center, Department of Radiology, Chicago, IL (United States); Adegunsoye, Ayodeji; Vij, Rekha; Noth, Imre; Strek, Mary E. [University of Chicago Medical Center, Section of Pulmonary/Critical Care, Department of Medicine, Chicago, IL (United States); Oldham, Justin M. [University of California at Davis, Section of Pulmonary/Critical Care, Department of Medicine, Sacramento, CA (United States); Husain, Aliya N. [University of Chicago Medical Center, Department of Pathology, Chicago, IL (United States)

    2017-12-15

    To identify CT findings in chronic hypersensitivity pneumonitis (cHP) associated with survival. Two thoracic radiologists assessed CT scans for specific imaging findings and patterns in 132 subjects with cHP. Survival analyses were performed. The majority of subjects had an inconsistent with usual interstitial pneumonitis pattern on CT (55.3%,73/132). Hypersensitivity pneumonitis (HP) diagnosis on CT was less common in those with fibrosis (66.1%, 74/112) than those without fibrosis (85%,17/20). Smoking was associated with a lower prevalence of HP on CT (p=0.04). CT features of pulmonary fibrosis, especially traction bronchiectasis (HR 8.34, 95% CI 1.98-35.21) and increased pulmonary artery (PA)/aorta ratio (HR 2.49, 95% CI 1.27-4.89) were associated with worse survival, while ground-glass opacity (HR 0.31, 95% CI 0.12-0.79) was associated with improved survival. Survival association with imaging was less pronounced after adjustment for gender, age and physiology score. A substantial proportion of cHP cases have a non-HP-like appearance. Ground-glass opacity, pulmonary fibrosis features and elevated PA/aorta ratio on CT likely reflect varying degrees of disease severity in cHP and may inform future clinical prediction models. (orig.)

  19. CT findings in brain edema following the administration of corticosteroids

    International Nuclear Information System (INIS)

    Seki, Yojiro; Kumagai, Norimoto; Aiba, Tadashi

    1979-01-01

    Computed tomography (CT) is the first noninvasive method available for directly visualizing brain edema in man. On CT scans perifocal edema is shown as an area of low density surrounding a lesion. The purpose of this report is to evaluate the effect of corticosteroids on brain edema as seen by CT (HITACHI CT-H 250). Nine patients with brain-tumor and one with brain-abscess were treated with betamethasone for about ten days (dosage started with 12 - 16 mg/day, and tapered). In eight cases, and improvement in the neurological findings was observed. An impressive reduction of peritumoral edema was shown on CT scans in six of these eight cases. There was, however, no significant correlation between the degree of the reduction of edema on CT and that of the improvement in neurological findings. The mode of the CT number in the region of edema did not differ significantly between pre- and post-steroid treatment in the cases showing a recognizable reduction of edema on CT. This failure to change is probably due to the insufficient mechanical accuracy of the CT scanner at the present stage of technology. Through our experiences, it seems that CT is one of the most promising tools for a dynamic study of brain edema in man. (author)

  20. CT findings in brain edema following the administration of corticosteroids

    Energy Technology Data Exchange (ETDEWEB)

    Seki, Y; Kumagai, N; Aiba, T [Toranomon Hospital, Tokyo (Japan)

    1979-03-01

    Computed tomography (CT) is the first noninvasive method available for directly visualizing brain edema in man. On CT scans perifocal edema is shown as an area of low density surrounding a lesion. The purpose of this report is to evaluate the effect of corticosteroids on brain edema as seen by CT (HITACHI CT-H 250). Nine patients with brain-tumor and one with brain-abscess were treated with betamethasone for about ten days (dosage started with 12 - 16 mg/day, and tapered). In eight cases, and improvement in the neurological findings was observed. An impressive reduction of peritumoral edema was shown on CT scans in six of these eight cases. There was, however, no significant correlation between the degree of the reduction of edema on CT and that of the improvement in neurological findings. The mode of the CT number in the region of edema did not differ significantly between pre- and post-steroid treatment in the cases showing a recognizable reduction of edema on CT. This failure to change is probably due to the insufficient mechanical accuracy of the CT scanner at the present stage of technology. Through our experiences, it seems that CT is one of the most promising tools for a dynamic study of brain edema in man.

  1. CT findings of isthmic spondylolisthesis and degenerative spondylolisthesis

    International Nuclear Information System (INIS)

    Chang, Suk Kyeong; Cho, Seong II; Chung, Gyung Ho; Lee, Sang Yong; Han, Young Min; Sohn, Myung Hee; Kim, Chong Soo; Choi, Ki Chul

    1996-01-01

    CT evaluate the finding useful for differential diagnosis and associated abnormalities of isthmic spondylolisthesis and degenerative spondylolisthesis on CT. We reviewed retrospectively the CT images of 164 patients who were diagnosed spondylolisthesis. One hundred twelve patients had isthmic spondylolisthesis and 52 patients had degenerative spondylolisthesis. Isthmic spondylolisthesis most frequently occurred at L5. The degree of anterior displacement was grade I and II. The defect had a horizontal plane, an irregular surface, a sclerotic margin, and protruding hypertrophic bony spur in the spinal canal. The most frequently associated structural abnormality was a herniated nucleus pulposus at the upper level of the defect. Degenerative spondylolisthesis most frequently occurred at L4-5 and were grade I. The degenerative facet joint had a vertical plane, a hypertrophic bony spur, and a vacuum facet phenomenon. We frequently detected a pseudobulging disk. The most frequently associated structural abnormality was a herniated nucleus pulposus at the level of the displacement. In spondylolisthesis, the findings in CT were valuable for differential diagnosis of isthmic and degenerative types and the detection of associated symptomatic abnormalities

  2. A high-throughput, multi-channel photon-counting detector with picosecond timing

    CERN Document Server

    Lapington, J S; Miller, G M; Ashton, T J R; Jarron, P; Despeisse, M; Powolny, F; Howorth, J; Milnes, J

    2009-01-01

    High-throughput photon counting with high time resolution is a niche application area where vacuum tubes can still outperform solid-state devices. Applications in the life sciences utilizing time-resolved spectroscopies, particularly in the growing field of proteomics, will benefit greatly from performance enhancements in event timing and detector throughput. The HiContent project is a collaboration between the University of Leicester Space Research Centre, the Microelectronics Group at CERN, Photek Ltd., and end-users at the Gray Cancer Institute and the University of Manchester. The goal is to develop a detector system specifically designed for optical proteomics, capable of high content (multi-parametric) analysis at high throughput. The HiContent detector system is being developed to exploit this niche market. It combines multi-channel, high time resolution photon counting in a single miniaturized detector system with integrated electronics. The combination of enabling technologies; small pore microchanne...

  3. Noise variance analysis using a flat panel x-ray detector: A method for additive noise assessment with application to breast CT applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang Kai; Huang, Shih-Ying; Packard, Nathan J.; Boone, John M. [Department of Radiology, University of California, Davis Medical Center, 4860 Y Street, Suite 3100 Ellison Building, Sacramento, California 95817 (United States); Department of Radiology, University of California, Davis Medical Center, 4860 Y Street, Suite 3100 Ellison Building, Sacramento, California 95817 (United States) and Department of Biomedical Engineering, University of California, Davis, Davis, California, 95616 (United States)

    2010-07-15

    Purpose: A simplified linear model approach was proposed to accurately model the response of a flat panel detector used for breast CT (bCT). Methods: Individual detector pixel mean and variance were measured from bCT projection images acquired both in air and with a polyethylene cylinder, with the detector operating in both fixed low gain and dynamic gain mode. Once the coefficients of the linear model are determined, the fractional additive noise can be used as a quantitative metric to evaluate the system's efficiency in utilizing x-ray photons, including the performance of different gain modes of the detector. Results: Fractional additive noise increases as the object thickness increases or as the radiation dose to the detector decreases. For bCT scan techniques on the UC Davis prototype scanner (80 kVp, 500 views total, 30 frames/s), in the low gain mode, additive noise contributes 21% of the total pixel noise variance for a 10 cm object and 44% for a 17 cm object. With the dynamic gain mode, additive noise only represents approximately 2.6% of the total pixel noise variance for a 10 cm object and 7.3% for a 17 cm object. Conclusions: The existence of the signal-independent additive noise is the primary cause for a quadratic relationship between bCT noise variance and the inverse of radiation dose at the detector. With the knowledge of the additive noise contribution to experimentally acquired images, system modifications can be made to reduce the impact of additive noise and improve the quantum noise efficiency of the bCT system.

  4. CT and MR imaging findings of sinonasal angiomatous polyps

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Jing [Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong (China); Man, Fengyuan [Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing (China); Deng, Kai [Department of Radiology, Qingdao No. 4 People' s Hospital, Qingdao, Shandong (China); Zheng, Yuanyuan [Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong (China); Hao, Dapeng, E-mail: haodp_2009@163.com [Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong (China); Xu, Wenjian, E-mail: cjr.xuwenjian@vip.163.com [Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong (China)

    2014-03-15

    Objective: To characterize the CT and MR imaging findings of patients with sinonasal angiomatous polyps (SAPs) and evaluate their respective clinical value in the diagnosis of SAP. Methods: CT and MR imaging findings of 15 patients with pathologically proven SAP were examined. Assessed image features included location, size, margin, attenuation, and change of the bony walls of the sinonasal cavity on CT, and signal intensity and enhancement pattern on MR. Results: On CT, the SAP was mostly isoattenuated with patches of slight hyperattenuation. Most lesions caused changes in the adjacent bone, including expansile remodeling (n = 8), defect or destruction (n = 7), and hyperostosis (n = 6). All lesions examined by MR showed heterogeneous isointense signal intensity on T1-weighted images and mixed obvious hyperintense and hypointense signal intensity with linear hypointense septum internally (n = 10), and hypointense peripheral rim on T2-weighted images (n = 10). Postcontrast MR images demonstrated areas of heterogeneous and marked enhancement with an unenhanced hypointense rim and septa (n = 7). Conclusions: CT and MR imaging have respective advantages in the diagnosis of SAP. Combined application of CT and MR examinations is necessary for patients with suspected SAP.

  5. CT and MR imaging findings of sinonasal angiomatous polyps

    International Nuclear Information System (INIS)

    Zou, Jing; Man, Fengyuan; Deng, Kai; Zheng, Yuanyuan; Hao, Dapeng; Xu, Wenjian

    2014-01-01

    Objective: To characterize the CT and MR imaging findings of patients with sinonasal angiomatous polyps (SAPs) and evaluate their respective clinical value in the diagnosis of SAP. Methods: CT and MR imaging findings of 15 patients with pathologically proven SAP were examined. Assessed image features included location, size, margin, attenuation, and change of the bony walls of the sinonasal cavity on CT, and signal intensity and enhancement pattern on MR. Results: On CT, the SAP was mostly isoattenuated with patches of slight hyperattenuation. Most lesions caused changes in the adjacent bone, including expansile remodeling (n = 8), defect or destruction (n = 7), and hyperostosis (n = 6). All lesions examined by MR showed heterogeneous isointense signal intensity on T1-weighted images and mixed obvious hyperintense and hypointense signal intensity with linear hypointense septum internally (n = 10), and hypointense peripheral rim on T2-weighted images (n = 10). Postcontrast MR images demonstrated areas of heterogeneous and marked enhancement with an unenhanced hypointense rim and septa (n = 7). Conclusions: CT and MR imaging have respective advantages in the diagnosis of SAP. Combined application of CT and MR examinations is necessary for patients with suspected SAP

  6. Cardiac CT diagnosis in acute coronary syndrome. Significance of delayed enhancement effect in myocardium

    International Nuclear Information System (INIS)

    Yamaguchi, Takayoshi

    2007-01-01

    Authors have found that the effect in the title (DEE) exists in cardiac CT images due to the contrasting agent used for percutaneous coronary intervention (PCI) done shortly after the onset of acute coronary syndrome (ACS). To confirm the finding, they compared images of the cardiac CT and blood flow single photon emission computed tomography (SPECT) obtained several days after ACS. The cardiac CT images of 17 patients (M 15, F 2; average age 63.6 y) with ACS were obtained 20-30 min after the successfully attained emergent enhanced PCI, with the 4-row multi detector low CT (MDCT) machine Aquilion (Toshiba) in synchronization to R-R interval for processing to multiplanar reconstructed (MPR) images. Thereafter (5.5 days in average), myocardial SPECT was conducted with 99m Tc-tetrofosmin (740 MBq), of which images were also processed to MPR ones. The CT and SPECT images were compared in coronary arterial territories assigned to 17 segments in the left ventricle and to 20 areas in the Bull's-eye Map. Findings due to DEE in the former CT images were confirmed well correspondent with the lesion found in the latter SPECT, indicating that DEE is a useful tool for evaluation of ACS severity. (R.T.)

  7. US and CT findings in the diagnosis of tuberculous peritonitis

    Energy Technology Data Exchange (ETDEWEB)

    Demirkazik, F.B. [Dept. of Radiology, School of Medicine, Hacettepe Univ., Ankara (Turkey); Akhan, O. [Dept. of Radiology, School of Medicine, Hacettepe Univ., Ankara (Turkey); Oezmen, M.N. [Dept. of Radiology, School of Medicine, Hacettepe Univ., Ankara (Turkey); Akata, D. [Dept. of Radiology, School of Medicine, Hacettepe Univ., Ankara (Turkey)

    1996-07-01

    Purpose: To evaluate the ultrasonographic and CT findings of tuberculous peritonitis. Material and Methods: Ultrasonographic and CT findings of 11 patients with the ascitic type of tuberculous peritonitis were reviewed. Results: All patients had ascites, and ultrasonography (US) demonstrated fine complete and incomplete mobile septations in 10 patients. In 5 of them, the ascites had a lattice-like appearance. Diffuse regular peritoneal thickening was detected in all patients by CT and in 10 patients by US. CT demonstrated infiltration of the greater omentum in 9 patients, whereas US showed omental thickening in only 5 patients. Conclusion: Peritoneal and omental thickening detected by CT and ascites with fine, mobile septations shown by US strongly suggest the ascitic type of tuberculous peritonitis. The 2 imaging modalities should be used together for accurate diagnosis of tuberculous peritonitis. (orig.).

  8. US and CT findings in the diagnosis of tuberculous peritonitis

    International Nuclear Information System (INIS)

    Demirkazik, F.B.; Akhan, O.; Oezmen, M.N.; Akata, D.

    1996-01-01

    Purpose: To evaluate the ultrasonographic and CT findings of tuberculous peritonitis. Material and Methods: Ultrasonographic and CT findings of 11 patients with the ascitic type of tuberculous peritonitis were reviewed. Results: All patients had ascites, and ultrasonography (US) demonstrated fine complete and incomplete mobile septations in 10 patients. In 5 of them, the ascites had a lattice-like appearance. Diffuse regular peritoneal thickening was detected in all patients by CT and in 10 patients by US. CT demonstrated infiltration of the greater omentum in 9 patients, whereas US showed omental thickening in only 5 patients. Conclusion: Peritoneal and omental thickening detected by CT and ascites with fine, mobile septations shown by US strongly suggest the ascitic type of tuberculous peritonitis. The 2 imaging modalities should be used together for accurate diagnosis of tuberculous peritonitis. (orig.)

  9. Neonatal cerebral infarction; Symptoms, CT findings and prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, Shinji; Togari, Hajime; Sobajima, Hisanori; Suzuki, Shigesumi; Wada, Yoshiro (Nagoya City Univ. (Japan). Faculty of Medicine); Yokochi, Kenji; Nishimura, Yutaka; Inukai, Kazuhisa; Futamura, Masahide

    1992-01-01

    In a retrospective multi-center study, we investigated eighteen infants with unilateral cerebral infarctions confirmed by computed tomography (CT) scans. The initial symptoms were observed in all the patients between 0 and 3 days of age. Convulsions or apneic attacks were the initial symptoms in all but one. Only 4 patients had complicated obstetric histories and none showed polycythemia or electrolyte abnormalities. All of the initial CT scans revealed unilaterally localized hypodense areas. In 10, the initial CT scans were performed within 24 hours after the clinical onset. In 16, the lesions were within the territory of the middle cerebral artery, 9 of which also involved the cortico-spinal tract (CST). In the remaining 2 patients, the lesions were located whithin the territory of the posterior cerebral artery. None of the 9 patients without CST involvement developed hemiplegia, whereas 5 (56%) of the 9 with CST involvement had hemiplegia, which is a fairly low incidence compared with that in adult cases. This difference was thought to be related to neonatal brain plasticity. (author).

  10. Lead arthropathy: radiographic, CT and MRI findings

    International Nuclear Information System (INIS)

    Fernandes, Joao Luiz; Lopes Rocha, Arthemizio Antonio; Veloso Ayrimoraes Soares, Mayra; Lopes Viana, Sergio

    2007-01-01

    Lead arthropathy is a well-known complication of gunshot injuries with retained intra-articular bullets. Although several previous reports have discussed the radiological findings of this entity, computed tomography (CT) and magnetic resonance imaging (MRI) findings have never been described before in this setting. In this paper the authors review the imaging findings of 11 patients with lead arthropathy (1 of whom had clinical signs of lead poisoning as well), all of them studied by means of radiographs. In addition, non-enhanced CT scans were obtained in 3 patients and gadolinium-enhanced MRI in 1. Classic findings of intra-articular speckled lead deposits (occasionally with a ''lead arthrogram'' appearance), joint space narrowing and preserved bone density were found at radiographs in the great majority of cases. Furthermore, extension of intra-articular lead to adjacent tendon sheaths was observed in almost half of the patients, an observation rarely reported in the literature. CT scans and MRI, in their turn, were superior with regard to soft tissue abnormalities, accurately depicting joint effusion and the thickened synovium with lead particles embedded in it. Post-gadolinium MRI had the advantage of showing the enhancement pattern of the inflamed synovium and associated bone marrow edema pattern. Although it is not possible to establish the role of axial imaging in lead arthropathy from the small number of cases studied, this initial experience shows that both methods hold promise in this setting and may be useful, at least in selected cases. (orig.)

  11. Concepts for dose determination in flat-detector CT

    Science.gov (United States)

    Kyriakou, Yiannis; Deak, Paul; Langner, Oliver; Kalender, Willi A.

    2008-07-01

    Flat-detector computed tomography (FD-CT) scanners provide large irradiation fields of typically 200 mm in the cranio-caudal direction. In consequence, dose assessment according to the current definition of the computed tomography dose index CTDIL=100 mm, where L is the integration length, would demand larger ionization chambers and phantoms which do not appear practical. We investigated the usefulness of the CTDI concept and practical dosimetry approaches for FD-CT by measurements and Monte Carlo (MC) simulations. An MC simulation tool (ImpactMC, VAMP GmbH, Erlangen, Germany) was used to assess the dose characteristics and was calibrated with measurements of air kerma. For validation purposes measurements were performed on an Axiom Artis C-arm system (Siemens Medical Solutions, Forchheim, Germany) equipped with a flat detector of 40 cm × 30 cm. The dose was assessed for 70 kV and 125 kV in cylindrical PMMA phantoms of 160 mm and 320 mm diameter with a varying phantom length from 150 to 900 mm. MC simulation results were compared to the values obtained with a calibrated ionization chambers of 100 mm and 250 mm length and to thermoluminesence (TLD) dose profiles. The MCs simulations were used to calculate the efficiency of the CTDIL determination with respect to the desired CTDI∞. Both the MC simulation results and the dose distributions obtained by MC simulation were in very good agreement with the CTDI measurements and with the reference TLD profiles, respectively, to within 5%. Standard CTDI phantoms which have a z-extent of 150 mm underestimate the dose at the center by up to 55%, whereas a z-extent of >=600 mm appears to be sufficient for FD-CT; the baseline value of the respective profile was within 1% to the reference baseline. As expected, the measurements with ionization chambers of 100 mm and 250 mm offer a limited accuracy, whereas an increased integration length of >=600 mm appeared to be necessary to approximate CTDI∞ in within 1%. MC simulations

  12. Thoracic manifestation of Wegener's granulomatosis: CT findings in 30 patients

    International Nuclear Information System (INIS)

    Lee, Kyung Soo; Kim, Tae Sung; Kim, Eun A.; Fujimoto, Kiminori; Moriya, Hiroshi; Watanabe, Hideyuki; Tateishi, Ukihide; Ashizawa, Kazuoto; Johkoh, Takeshi; Kwon, O. Jung

    2003-01-01

    Our objective was to describe the CT findings of thoracic Wegener's granulomatosis. At presentation, both conventional and thin-section CT scans were available in 30 patients with Wegener's granulomatosis. Serial CT scans (range of intervals: 1-25 months, mean 4.5 months) were available in 20 patients. The initial and follow-up CT scans were analyzed retrospectively by two observers in terms of pattern and extent of parenchymal and airway lesions. Positive CT findings were seen in 29 of 30 (97%) patients at initial presentation. The most common pattern was nodules or masses seen in 27 of 30 (90%) patients. They were multiple in 23 of 27 (85%) patients, bilateral in 18 (67%), subpleural in 24 (89%), and peribronchovascular in 11 (41%) in distribution. Bronchial wall thickening in the segmental or subsegmental bronchi was seen in 22 (73%) patients. Large airways were also abnormal in 9 (30%) patients. Patchy areas of consolidation and ground-glass opacity were seen in 7 (23%) patients, respectively. In 17 of 20 (85%) patients in whom follow-up CT scans were available, the parenchymal or airway lesion showed complete or partial improvement with treatment. The CT findings of Wegener's granulomatosis, although multiple and variable, consist mainly of bilateral subpleural or peribronchovascular nodules or masses and bronchial wall thickening in the segmental or subsegmental bronchi. Parenchymal and airway lesions improve with treatment in most patients. (orig.)

  13. Nosocomial rapidly growing mycobacterial infections following laparoscopic surgery: CT imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Volpato, Richard [Cassiano Antonio de Moraes University Hospital, Department of Diagnostic Radiology, Vitoria, ES (Brazil); Campi de Castro, Claudio [University of Sao Paulo Medical School, Department of Radiology, Cerqueira Cesar, Sao Paulo (Brazil); Hadad, David Jamil [Cassiano Antonio de Moraes University Hospital, Nucleo de Doencas Infecciosas, Department of Internal Medicine, Vitoria, ES (Brazil); Silva Souza Ribeiro, Flavya da [Laboratorio de Patologia PAT, Department of Diagnostic Radiology, Unit 1473, Vitoria, ES (Brazil); Filho, Ezequiel Leal [UNIMED Diagnostico, Department of Diagnostic Radiology, Unit 1473, Vitoria, ES (Brazil); Marcal, Leonardo P. [The University of Texas M D Anderson Cancer Center, Department of Diagnostic Radiology, Unit 1473, Houston, TX (United States)

    2015-09-15

    To identify the distribution and frequency of computed tomography (CT) findings in patients with nosocomial rapidly growing mycobacterial (RGM) infection after laparoscopic surgery. A descriptive retrospective study in patients with RGM infection after laparoscopic surgery who underwent CT imaging prior to initiation of therapy. The images were analyzed by two radiologists in consensus, who evaluated the skin/subcutaneous tissues, the abdominal wall, and intraperitoneal region separately. The patterns of involvement were tabulated as: densification, collections, nodules (≥1.0 cm), small nodules (<1.0 cm), pseudocavitated nodules, and small pseudocavitated nodules. Twenty-six patients met the established criteria. The subcutaneous findings were: densification (88.5 %), small nodules (61.5 %), small pseudocavitated nodules (23.1 %), nodules (38.5 %), pseudocavitated nodules (15.4 %), and collections (26.9 %). The findings in the abdominal wall were: densification (61.5 %), pseudocavitated nodules (3.8 %), and collections (15.4 %). The intraperitoneal findings were: densification (46.1 %), small nodules (42.3 %), nodules (15.4 %), and collections (11.5 %). Subcutaneous CT findings in descending order of frequency were: densification, small nodules, nodules, small pseudocavitated nodules, pseudocavitated nodules, and collections. The musculo-fascial plane CT findings were: densification, collections, and pseudocavitated nodules. The intraperitoneal CT findings were: densification, small nodules, nodules, and collections. (orig.)

  14. Nosocomial rapidly growing mycobacterial infections following laparoscopic surgery: CT imaging findings

    International Nuclear Information System (INIS)

    Volpato, Richard; Campi de Castro, Claudio; Hadad, David Jamil; Silva Souza Ribeiro, Flavya da; Filho, Ezequiel Leal; Marcal, Leonardo P.

    2015-01-01

    To identify the distribution and frequency of computed tomography (CT) findings in patients with nosocomial rapidly growing mycobacterial (RGM) infection after laparoscopic surgery. A descriptive retrospective study in patients with RGM infection after laparoscopic surgery who underwent CT imaging prior to initiation of therapy. The images were analyzed by two radiologists in consensus, who evaluated the skin/subcutaneous tissues, the abdominal wall, and intraperitoneal region separately. The patterns of involvement were tabulated as: densification, collections, nodules (≥1.0 cm), small nodules (<1.0 cm), pseudocavitated nodules, and small pseudocavitated nodules. Twenty-six patients met the established criteria. The subcutaneous findings were: densification (88.5 %), small nodules (61.5 %), small pseudocavitated nodules (23.1 %), nodules (38.5 %), pseudocavitated nodules (15.4 %), and collections (26.9 %). The findings in the abdominal wall were: densification (61.5 %), pseudocavitated nodules (3.8 %), and collections (15.4 %). The intraperitoneal findings were: densification (46.1 %), small nodules (42.3 %), nodules (15.4 %), and collections (11.5 %). Subcutaneous CT findings in descending order of frequency were: densification, small nodules, nodules, small pseudocavitated nodules, pseudocavitated nodules, and collections. The musculo-fascial plane CT findings were: densification, collections, and pseudocavitated nodules. The intraperitoneal CT findings were: densification, small nodules, nodules, and collections. (orig.)

  15. Nosocomial rapidly growing mycobacterial infections following laparoscopic surgery: CT imaging findings.

    Science.gov (United States)

    Volpato, Richard; de Castro, Claudio Campi; Hadad, David Jamil; da Silva Souza Ribeiro, Flavya; Filho, Ezequiel Leal; Marcal, Leonardo P

    2015-09-01

    To identify the distribution and frequency of computed tomography (CT) findings in patients with nosocomial rapidly growing mycobacterial (RGM) infection after laparoscopic surgery. A descriptive retrospective study in patients with RGM infection after laparoscopic surgery who underwent CT imaging prior to initiation of therapy. The images were analyzed by two radiologists in consensus, who evaluated the skin/subcutaneous tissues, the abdominal wall, and intraperitoneal region separately. The patterns of involvement were tabulated as: densification, collections, nodules (≥1.0 cm), small nodules (<1.0 cm), pseudocavitated nodules, and small pseudocavitated nodules. Twenty-six patients met the established criteria. The subcutaneous findings were: densification (88.5%), small nodules (61.5%), small pseudocavitated nodules (23.1 %), nodules (38.5%), pseudocavitated nodules (15.4%), and collections (26.9%). The findings in the abdominal wall were: densification (61.5%), pseudocavitated nodules (3.8%), and collections (15.4%). The intraperitoneal findings were: densification (46.1%), small nodules (42.3%), nodules (15.4%), and collections (11.5%). Subcutaneous CT findings in descending order of frequency were: densification, small nodules, nodules, small pseudocavitated nodules, pseudocavitated nodules, and collections. The musculo-fascial plane CT findings were: densification, collections, and pseudocavitated nodules. The intraperitoneal CT findings were: densification, small nodules, nodules, and collections. • Rapidly growing mycobacterial infection may occur following laparoscopy. • Post-laparoscopy mycobacterial infection CT findings are densification, collection, and nodules. • Rapidly growing mycobacterial infection following laparoscopy may involve the peritoneal cavity. • Post-laparoscopy rapidly growing mycobacterial intraperitoneal infection is not associated with ascites or lymphadenopathy.

  16. Experimental MRI-SPECT insert system with Hybrid Semiconductor detectors Timepix for MR animal scanner Bruker 47/20

    Czech Academy of Sciences Publication Activity Database

    Zajíček, J.; Burian, M.; Soukup, P.; Novák, Vladimír; Macko, M.; Jakůbek, J.

    2017-01-01

    Roč. 12, January (2017), č. článku P01015. ISSN 1748-0221 Institutional support: RVO:68378297 Keywords : Gamma camera * SPECT * PET PET /CT * coronary CT angiography (CTA) * Gamma detectors (scintillators, CZT, HPG, HgI etc) * multi-modality systems * pixelated detectors and associated VLSI electronics Subject RIV: JB - Sensors, Measurment, Regulation OBOR OECD: Electrical and electronic engineering Impact factor: 1.220, year: 2016 http://iopscience.iop.org/article/10.1088/1748-0221/12/01/P01015

  17. CT and MRI of germ-cell tumors with metastasis or multi-located tumors

    International Nuclear Information System (INIS)

    Miyagami, Mitsusuke; Tazoe, Makoto; Tsubokawa, Takashi

    1989-01-01

    Twenty-seven cases of germ-cell tumors were examined with a CT scan in our clinic. In the 11 cases of metastasis or multi-localized tumors, the CT findings were studied in connection with the MRI findings. There were 6 cases of germ-cell tumors which had broad infiltrating tumors with multiple lesions on first admission. Their tumor sites were different from that in cases of malignant glioma, being frequently localized in the pineal and/or the suprasellar region, on the wall of the third and/or lateral ventricle, and in the region of the basal ganglia. Five of the cases of germ-cell tumors had metastasis with various patterns connected to a remote area - that is, to spinal cords, to the ventricular wall and basal cistern of the brain stem by CSF dissemination, to a lung by hematogeneous metastasis, and to the peritoneal wall or organs by a V-P shunt. The CT findings of germ-cell tumors were correlated mainly with the results of the histological diagnosis; they were found not to differ with the tumor site. The germinoma in the suprasellar region had less calcification than in the pineal region. Cysts, calcification, and an enlargement of the lateral ventricle on the tumor side were frequently seen in the germinoma of the basal ganglia. On the MRI of 5 cases of germinoma, the T 1 -weighted image revealed a slightly low or iso signal intensity, while the T 2 -weighted image showed a high signal intensity. In the case of multiple tumor lesions, some cases demonstrated different CT findings and radiosensitivities for each tumor. The possibility of a multicentric origin for the tumors is thus suggested in some cases of germ-cell tumors. (author)

  18. Pitch dependence of longitudinal sampling and aliasing effects in multi-slice helical computed tomography (CT)

    International Nuclear Information System (INIS)

    La Riviere, Patrick J.; Pan Xiaochuan

    2002-01-01

    In this work, we investigate longitudinal sampling and aliasing effects in multi-slice helical CT. We demonstrate that longitudinal aliasing can be a significant, complicated, and potentially detrimental effect in multi-slice helical CT reconstructions. Multi-slice helical CT scans are generally undersampled longitudinally for all pitches of clinical interest, and the resulting aliasing effects are spatially variant. As in the single-slice case, aliasing is shown to be negligible at the isocentre for circularly symmetric objects due to a fortuitous aliasing cancellation phenomenon. However, away from the isocentre, aliasing effects can be significant, spatially variant, and highly pitch dependent. This implies that measures more sophisticated than isocentre slice sensitivity profiles are needed to characterize longitudinal properties of multi-slice helical CT systems. Such measures are particularly important in assessing the question of whether there are preferred pitches in helical CT. Previous analyses have generally focused only on isocentre sampling patterns, and our more global analysis leads to somewhat different conclusions than have been reached before, suggesting that pitches 3, 4, 5, and 6 are favourable, and that half-integer pitches are somewhat suboptimal. (author)

  19. Role of mediastinal and multi-organ CT scans in staging presumable surgical candidates with non-small-cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Osada, Hiroaki; Nakajima, Yasuo; Taira, Yasuhiko; Yokote, Kumio; Noguchi, Teruhiko

    1987-09-01

    In order to evaluate the role of CT scan and bone scan in staging patients with non-small-cell lung cancer presumably indicated for surgery, 70 consecutive patients who underwent thoracotomy were reviewed. Most of them received mediastinal and multi-organ (brain, liver and adrenal) CT scans and a bone scan. In the most recent 40 of the 70 patients, CT findings of the mediastinal lymph nodes were compared to the pathology following complete sampling. The overall accuracy of the mediastinal CT was 60.0 per cent (12 true positive and 12 true negative), but the negative predictable value was 12/(12 + 3) or 80.0 per cent, whereas 3 were false negatives though they showed an acceptable postoperative course. Sixteen out of 21 patients with one, or at the most, three enlarged nodes detected on CT also did well postoperatively and retrospectively, were considered not to have required mediastinoscopy. A group of patients showing no, or at the most, three enlarged mediastinal lymph nodes on CT may be considered as candidates for surgery even without mediastinoscopy. Multi-organ survey by means of CT was believed cost-ineffective and omittable. Bone scan however, retrospectively detected three true positives among 20 patients with a positive uptake, so that it cannot be omitted out of hand, though further examination of this point is required.

  20. Multi-slice spiral CT perfusion imaging of chronic obstructive pulmonary disease

    International Nuclear Information System (INIS)

    Shao Yanhui; Qian Nong; Xue Yuejun; Dao Yinhong

    2008-01-01

    Objective: To evaluate the diagnostic value of multi-slice spiral CT (MSCT) perfusion imaging in chronic obstructive pulmonary disease (COPD). Methods: Twenty COPD patients and 20 volunteers underwent 8-row detector spiral CT (MSCT) perfusion imaging using cine scan mode with 5 mm slice thickness, 0.5 s rotation time and a total scan time of 45 s with 5 s intervals. 60 ml contrast agent (300 nag I/ml) were administered at a rate of 4 ml/s from the forearm superficial vein. The imaging data were transferred to a workstation. A time-density curve and pseudo-color map were generated automatically with GE CT perfusion 3 software, the blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface (PS) were measured. Results: Time-density curve was flatter and the peak of the curve was obviously lower in COPD patients than the volunteers. The BF, BV, PS in COPD patients was (24.77±11.49) ml·min -1 ·100 g -1 , (2.48±1.02) ml/100 g and (2.75±1.13) ml· min -1 ·100 g -1 respectively. In volunteers was (290.14±107.59) ml·min -1 ·100 g -1 , (16.51 ± 5.98) ml/100 g, (8.80±3.03) ml·min -1 ·100 g -1 respectively. The MTT in COPD patients and volunteers was (10.58±4.85) s and (4.50±1.71)s respectively. The BF, BV and PS in COPD patients was lower than the volunteers, the MTY was higher (P<0.01). Conclusion: MSCT perfusion imaging is helpful for the diagnosis of COPD. (authors)

  1. Basic and clinical studies of visualizing right inferior phrenic artery by multi detector row-CT

    International Nuclear Information System (INIS)

    Okumura, Yusuke; Takahashi, Shiro; Suzuki, Masayuki; Takemura, Akihiro; Matsui, Osamu; Takada, Tadanori; Kawahara, Kazuhiro; Matsuura, Yukihiro

    2007-01-01

    To perform transcatheter arterial embolization (TAE) successfully, it is important to obtain information about parasitic arterial supply to the hepatocellular carcinoma (HCC). Among these extrahepatic collateral vessels, the right inferior phrenic artery (RIPA) is the most frequent and important extrahepatic collateral artery supplying the HCC. In the present study, we obtained multi-planar reformation (MPR) images of RIPA using multi detector row computed tomography (MDCT), assessed the ability of MDCT to demonstrate the origin of RIPA, and then analyzed the morphology of the origin. In a basic study using an original phantom simulating vessel origin, the origin was poorly visualized depending on the phantom diameter and angle of the origin to the scanned section. A clinical study was performed in 28 patients with HCC who underwent both MDCT and angiography within a short period. In 19 of 28 patients, RIPA originated at the celiac artery. In 3 patients, RIPA originated at the right renal artery, and in 6, directly at the abdominal aorta. The origin of RIPA was categorized into four patterns according to the inclination of the origin on transverse sections of MDCT. RIPA that originated at the right renal artery and showed an upward course perpendicular to the scan section of MDCT were most clearly visualized at the origin. In addition, RIPA could be observed in an optional direction on the workstation. Pre-angiographic visualization of the origin of RIPA may save angiographic time, curtail contrast medium, and reduce radiation exposure. (author)

  2. Extra colonic Findings on CT Colonography in Symptomatic Patients

    International Nuclear Information System (INIS)

    Drahovska, I.; Nigut, F.; Mach, P.; Lazurova, I.; Gombosova, L.

    2011-01-01

    The paper is an analysis of the consequences of the extra colonic findings identified on CT colonography examination of symptomatic patients and the validity of the intravenous application of contrast medium in this examination. The authors enrolled 252 patients, who underwent CT colonogprahy.128 extra colonic findings was identified in 80 patients (31.74%). The average age was 65.62 years (SD = 12.7, min. age was 29, max. age. 85 years). According the clinical significance the extra colonic findings have been divided into three groups – low, moderate and very important extra colonic findings. Low significant findings were 68 (53.12%), moderate 26 (20.31%) and very important extra colonic findings were 34 (26.56%), of which 30 were malignant nature. (author)

  3. Artifact reduction of different metallic implants in flat detector C-arm CT.

    Science.gov (United States)

    Hung, S-C; Wu, C-C; Lin, C-J; Guo, W-Y; Luo, C-B; Chang, F-C; Chang, C-Y

    2014-07-01

    Flat detector CT has been increasingly used as a follow-up examination after endovascular intervention. Metal artifact reduction has been successfully demonstrated in coil mass cases, but only in a small series. We attempted to objectively and subjectively evaluate the feasibility of metal artifact reduction with various metallic objects and coil lengths. We retrospectively reprocessed the flat detector CT data of 28 patients (15 men, 13 women; mean age, 55.6 years) after they underwent endovascular treatment (20 coiling ± stent placement, 6 liquid embolizers) or shunt drainage (n = 2) between January 2009 and November 2011 by using a metal artifact reduction correction algorithm. We measured CT value ranges and noise by using region-of-interest methods, and 2 experienced neuroradiologists rated the degrees of improved imaging quality and artifact reduction by comparing uncorrected and corrected images. After we applied the metal artifact reduction algorithm, the CT value ranges and the noise were substantially reduced (1815.3 ± 793.7 versus 231.7 ± 95.9 and 319.9 ± 136.6 versus 45.9 ± 14.0; both P metallic objects and various sizes of coil masses. The rater study achieved an overall improvement of imaging quality and artifact reduction (85.7% and 78.6% of cases by 2 raters, respectively), with the greatest improvement in the coiling group, moderate improvement in the liquid embolizers, and the smallest improvement in ventricular shunting (overall agreement, 0.857). The metal artifact reduction algorithm substantially reduced artifacts and improved the objective image quality in every studied case. It also allowed improved diagnostic confidence in most cases. © 2014 by American Journal of Neuroradiology.

  4. Comparative study on findings of the brain computed tomography (X-ray-CT) and dynamic topography of VEP (VDT)

    International Nuclear Information System (INIS)

    Matsuura, Masashi

    1985-01-01

    Comparative study between morphological Xray-CT and functional VDT was conducted on 20 cases of cerebral diseases with visual dysfunction. Subjects were patients with cerebral infarction, intracranial hemorrhage, hemispherectomy, traumatic brain atrophy, brain tumor, Creutzfeldt-Jakob disease, anoxic encephalopathy, porencephaly, microcephaly and optic tract lesion. VEP topography was performed by flash stimulation and brain electrical activity mappings were displayed by EEG topography computer. In 9 cases out of 20, abolished function in VDT was correlated to the defective findings of Xray-CT. Cases with homonymous hemianopsia showed 2 types of BEAM. In cases with a lesion in the inner surface of the occipital lobe, asymmetric electric activity was distributed along the sagittal axis of the scalp. While, in cases with outer surface lesion of the occipital lobe, asymmetric electric activity appeared along the coronary axis. In cases with multi focal brain lesions in Xray-CT, there was no regular tendency in abnormality of VDT. Various aberration of VEP and VDT, such as component defect, stagnation, reduction, condensation and abnormal flow were demonstrated. In a case of optic tract lesion, Xray-CT showed no pathological findings but VDT showed a remarkable asymmetry of brain activity. (author)

  5. A new method for measuring coronary artery diameters with CT spatial profile curves

    International Nuclear Information System (INIS)

    Shimamoto, Ryoichi; Suzuki, Jun-ichi; Yamazaki, Tadashi; Tsuji, Taeko; Ohmoto, Yuki; Morita, Toshihiro; Yamashita, Hiroshi; Honye, Junko; Nagai, Ryozo; Akahane, Masaaki; Ohtomo, Kuni

    2007-01-01

    Purpose: Coronary artery vascular edge recognition on computed tomography (CT) angiograms is influenced by window parameters. A noninvasive method for vascular edge recognition independent of window setting with use of multi-detector row CT was contrived and its feasibility and accuracy were estimated by intravascular ultrasound (IVUS). Methods: Multi-detector row CT was performed to obtain 29 CT spatial profile curves by setting a line cursor across short-axis coronary angiograms processed by multi-planar reconstruction. IVUS was also performed to determine the reference coronary diameter. IVUS diameter was fitted horizontally between two points on the upward and downward slopes of the profile curves and Hounsfield number was measured at the fitted level to test seven candidate indexes for definition of intravascular coronary diameter. The best index from the curves should show the best agreement with IVUS diameter. Results: Of the seven candidates the agreement was the best (agreement: 16 ± 11%) when the two ratios of Hounsfield number at the level of IVUS diameter over that at the peak on the profile curves were used with water and with fat as the background tissue. These edge definitions were achieved by cutting the horizontal distance by the curves at the level defined by the ratio of 0.41 for water background and 0.57 for fat background. Conclusions: Vascular edge recognition of the coronary artery with CT spatial profile curves was feasible and the contrived method could define the coronary diameter with reasonable agreement

  6. Renal infarction: CT diagnosis and correlation between CT findings and etiologies

    International Nuclear Information System (INIS)

    Wong, W.S.; Moss, A.A.; Federle, M.P.; Cochran, S.T.; London, S.S.

    1984-01-01

    The CT scans and the clinical records of 12 patients who had renal infarction were reviewed. The renal infarcts were classified as either focal or global. The CT findings were correlated with the etiologies of renal infarction. Embolism was the most common cause of renal infarcts that were multifocal with involvement of both kidneys. Trauma caused a unilateral global type of infract. A case of sickle cell anemia presented with multiple ''slit-like'' focal infarcts and enlarged kidneys. Forty-seven per cent of infarcts demonstrated the cortical rim sign, 11% were acapsular fluid collection, and 6% had an abnormally thickened renal fascia

  7. Terahertz detectors for long wavelength multi-spectral imaging.

    Energy Technology Data Exchange (ETDEWEB)

    Lyo, Sungkwun Kenneth; Wanke, Michael Clement; Reno, John Louis; Shaner, Eric Arthur; Grine, Albert D.

    2007-10-01

    The purpose of this work was to develop a wavelength tunable detector for Terahertz spectroscopy and imaging. Our approach was to utilize plasmons in the channel of a specially designed field-effect transistor called the grating-gate detector. Grating-gate detectors exhibit narrow-linewidth, broad spectral tunability through application of a gate bias, and no angular dependence in their photoresponse. As such, if suitable sensitivity can be attained, they are viable candidates for Terahertz multi-spectral focal plane arrays. When this work began, grating-gate gate detectors, while having many promising characteristics, had a noise-equivalent power (NEP) of only 10{sup -5} W/{radical}Hz. Over the duration of this project, we have obtained a true NEP of 10{sup -8} W/{radical}Hz and a scaled NEP of 10{sup -9}W/{radical}Hz. The ultimate goal for these detectors is to reach a NEP in the 10{sup -9{yields}-10}W/{radical}Hz range; we have not yet seen a roadblock to continued improvement.

  8. CT findings of pulmonary cryptococcosis in immunocompetent children

    International Nuclear Information System (INIS)

    Wang Bei; Peng Yun; Zhou Chunjun; Zhao Shunying

    2012-01-01

    Objective: The aim of our study was to study the CT findings of cryptococcosis in immunocompetent children. Methods: CT scan and clinical data of 21 immunocompetent children with proven pulmonary cryptococcosis were retrospectively collected and analyzed. Results: The CT scans demonstrated 1 mm subpleural nodule in the lingula of left lung in 1 patient and multiple nodules in 20 patients.Of 20 patients with multiple nodules, peripheral or subpleural distribution was found in 12 patients,and diffuse distribution in 8 patients. Of 20 patients with multiple nodules,Nodules of < 10 mm was found in 18 patients,< 3 mm in 14 patients, and > 10 mm in 2 patients. Round nodular with smooth margin was detected in 15 of 20 patients with multiple nodules. Lymphadenopathy was found in 17 patients including 3 patients with mild contrast enhancement and 2 patients with circular enhancement. Extrapulmonary lesions distributing in liver, spleen, kidney, and the nervous system were found in 14 patients. In follow-up, 1 patient died and 20 patients fully recovered. Conclusions: Pulmonary multiple nodules with lymphadenopathy is the characteristic CT findings in immunocompetent children with pulmonary cryptococcosis which is prone to involve multiple extra-pulmonary organs. (authors)

  9. Accuracy Improvement of Boron Meter Adopting New Fitting Function and Multi-Detector

    Directory of Open Access Journals (Sweden)

    Chidong Kong

    2016-12-01

    Full Text Available This paper introduces a boron meter with improved accuracy compared with other commercially available boron meters. Its design includes a new fitting function and a multi-detector. In pressurized water reactors (PWRs in Korea, many boron meters have been used to continuously monitor boron concentration in reactor coolant. However, it is difficult to use the boron meters in practice because the measurement uncertainty is high. For this reason, there has been a strong demand for improvement in their accuracy. In this work, a boron meter evaluation model was developed, and two approaches were considered to improve the boron meter accuracy: the first approach uses a new fitting function and the second approach uses a multi-detector. With the new fitting function, the boron concentration error was decreased from 3.30 ppm to 0.73 ppm. With the multi-detector, the count signals were contaminated with noise such as field measurement data, and analyses were repeated 1,000 times to obtain average and standard deviations of the boron concentration errors. Finally, using the new fitting formulation and multi-detector together, the average error was decreased from 5.95 ppm to 1.83 ppm and its standard deviation was decreased from 0.64 ppm to 0.26 ppm. This result represents a great improvement of the boron meter accuracy.

  10. Accuracy improvement of boron meter adopting new fitting function and multi-detector

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Chidong; Lee, Hyun Suk; Tak, Tae Woo; Lee, Deok Jung [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of); KIm, Si Hwan; Lyou, Seok Jean [Users Incorporated Company, Hansin S-MECA, Daejeon (Korea, Republic of)

    2016-12-15

    This paper introduces a boron meter with improved accuracy compared with other commercially available boron meters. Its design includes a new fitting function and a multi-detector. In pressurized water reactors (PWRs) in Korea, many boron meters have been used to continuously monitor boron concentration in reactor coolant. However, it is difficult to use the boron meters in practice because the measurement uncertainty is high. For this reason, there has been a strong demand for improvement in their accuracy. In this work, a boron meter evaluation model was developed, and two approaches were considered to improve the boron meter accuracy: the first approach uses a new fitting function and the second approach uses a multi-detector. With the new fitting function, the boron concentration error was decreased from 3.30 ppm to 0.73 ppm. With the multi-detector, the count signals were contaminated with noise such as field measurement data, and analyses were repeated 1,000 times to obtain average and standard deviations of the boron concentration errors. Finally, using the new fitting formulation and multi-detector together, the average error was decreased from 5.95 ppm to 1.83 ppm and its standard deviation was decreased from 0.64 ppm to 0.26 ppm. This result represents a great improvement of the boron meter accuracy.

  11. Thoracic CT findings at hypovolemic shock

    International Nuclear Information System (INIS)

    Rotondo, A.; Angelelli, G.; Catalano, O.; Grassi, R.; Scialpi, M.

    1998-01-01

    Purpose: To describe and discuss the thoracic CT features of hypovolemic shock. Material and Methods: From a group of 18 patients with signs of hypovolemia on contrast-enhanced abdominal CT, 11 were selected for our study as having also undergone a complete chest examination. Pulse rate, blood pressure, trauma score value, Glasgow coma scale value, surgical result, and final outcome were retrospectively evaluated. The CT features analyzed were: decreased cardiac volume, reduced caliber of the thoracic aorta, aortic branches and caval venous system, increased enhancement of the aorta, and increased enhancement of the pulmonary collapses/contusions. Results: All 11 subjects presented severe injuries and hemodynamic instability; 7 were stable enough to undergo surgery; only 1 of the 11 survived. Two patients showed none of the features of thoracic hypovolemia. All the other patients presented at least two signs: reduced caliber of the thoracic aorta in 7 cases; decreased volume of the cardiac chambers and increased aortic enhancement in 6; decreased caliber of the aortic vessels in 4; decreased caliber of the caval veins in 3; and increased enhancement of the pulmonary collapses/contusions in 3. Conclusions: In patients with hypovolemia, CT may show several thoracic findings in addition to abdominal ones. Knowledge of these features is important for distinguishing them from traumatic injuries. (orig.)

  12. Multi-detector CT urography: effect of oral hydration and contrast medium volume on renal parenchymal enhancement and urinary tract opacification - a quantitative and qualitative analysis

    International Nuclear Information System (INIS)

    Szolar, Dieter H.; Tillich, Manfred; Preidler, Klaus W.

    2010-01-01

    To assess the effect of oral hydration and contrast-medium volume on renal enhancement and urinary tract opacification in multi-detector CT urography. A total of 192 patients were assigned to different protocols with varying doses of contrast agent with and without oral hydration. The attenuation was measured in the renal parenchyma in the unenhanced, nephrographic and excretory phase, and in the urinary tract in excretory phase imaging, respectively. Opacification of the urinary tract was graded on volume rendered images. Oral hydration did not significantly alter renal parenchymal enhancement in both the nephrographic and the excretory phase (p > 0.001), but significantly decreased mean attenuation of the urinary tract in the excretory phase (p ≤ 0.001), and improved continuous opacification of all ureter segments (p < 0.01). Higher volumes of contrast medium improved renal parenchymal enhancement (p ≤ 0.001) and continuous opacification of the urinary tract (p ≤ 0.01). Oral hydration leads to lower attenuation values in the urinary tract but improves the continuous opacification of the tract. Increase in contrast medium volume leads to higher renal parenchymal enhancement as well as to an increased continuous opacification of the urinary tract. Decrease in contrast medium volume cannot be compensated for by oral hydration in terms of parenchymal enhancement. (orig.)

  13. Enhanced CT in the diagnosis of acute appendicitis to evaluate the severity of disease. Comparison of CT findings and histological diagnosis

    International Nuclear Information System (INIS)

    Mori, Yoshiko; Yamasaki, Michio; Furukawa, Akira; Takahashi, Masashi; Murata, Kiyoshi

    2001-01-01

    To assess the potential of CT in evaluating the histological severity of acute appendicitis in comparison with surgical and pathological findings. The CT images of 75 patients with surgically proven appendicitis, including 10 cases of catarrhal, 34 of phlegmonous, and 31 of gangrenous appendicitis, were retrospectively analyzed for the following five CT findings: hazy periappendiceal densities, enlarged appendix, increased enhancement of the appendiceal wall, increased enhancement of the periappendiceal intestinal wall, and deficiency of the appendiceal wall. By comparing all the CT findings and the pathological severity of appendicitis (catarrhal, phlegmonous, and gangrenous), the prevalence of the five CT findings was calculated for each pathological category. Abnormal CT findings were noted in only one case of catarrhal appendicitis. Increased enhancement of the appendiceal wall was observed in all 29 cases of phlegmonous appendicitis (100%), but in only 66.7% (18 cases) of gangrenous appendicitis. Deficiency of the appendiceal wall was more frequently observed in gangrenous (19/27, 70.4%) than phlegmonous appendicitis (4/29, 13.8%). Findings of enhanced CT provide useful information in evaluating the pathological severity of acute appendicitis. (author)

  14. Current status and requirements for position-sensitive detectors in medicine

    CERN Document Server

    Speller, R

    2002-01-01

    This review considers the current status of detector developments for medical imaging using ionising radiation. This field is divided into two major areas; the use of X-rays for transmission imaging and the use of radioactive tracers in emission imaging (nuclear medicine). Until recently, most detector developments were for applications in nuclear medicine. However, in the past 5 years new developments in large area, X-ray-sensitive detectors have meant that both application domains are equally served. In X-ray imaging, work in CT and mammography are chosen as examples of sensor developments. Photodiode arrays in multi-slice spiral CT acquisitions are described and for mammography the use of amorphous silicon flat panel arrays is considered. The latter is an excellent example where new detector developments have required a re-think of traditional imaging methods. In gamma-ray imaging the recent developments in small area, task-specific cameras are described. Their limitations and current proposals to overcome...

  15. CT and MR findings of the inverted papilloma

    International Nuclear Information System (INIS)

    Lim, Seong Youb; Kim, Hak Jin; Lee, Jun Woo; Park, Jae Yeong; Lee, Sung Gap; Kim, Byung Soo; Roh, Hwan Jung; Baik, Seung Kook

    1997-01-01

    The purpose of this study is to describe the CT and MR findings of inverted papilloma and to determine the specific differential finding between inverted papilloma with and without coexisting malignancy. Twenty-two histopathologically proven inverted papillomas were included in this study ; in six patients there was coexisting malignancy. Twenty-two CT images and eight MR images were retrospectively reviewed. On CT images, the inverted papillomas were seen as unilateral sinonasal masses with bone remodeling (n=15) rather than bone destruction (n=1) and showed iso- or slightly high attenuation. Three of the six malignant cases showed aggressive bone destruction and widespread extension into the orbit, intracranial and buccal spaces, and pterygopalatine fossa. On MR images, the inverted papillomas (n=3) were iso- (n=2) or slightly high (n=1) in signal intensity in relation to muscle on T1-weighted images, and high (n=3) on T2-weighted images. Gadolinium enhanced images showed heterogenous moderate enhancement. In the cases of coexisting malignancy (n=5), the masses were iso- (n=5) on T1-weighted images, high (n=5) on T2-weighted images and also showed heterogenous moderate enhancement. Inverted papilloma should be considered in the differential diagnosis of a bulky unilateral nasal mass extending into the adjacent paranasal sinuses, especially in an elderly patient with chronic nasal obstruction. Although there were no specific differential findings in signal intensity and enhancement pattern on CT and MR images between benign and malignant inverted papilloma, aggressive bone destruction and widespread extension beyond the sinonasal cavity are findings which are highly suggestive of coexisting malignancy

  16. Specific CT findings of eclampsia

    International Nuclear Information System (INIS)

    Takahashi, Hiroshi; Nakazawa, Shozo; Imaya, Hisatoshi

    1985-01-01

    Two cases of specific computed tomographic (CT) findings of eclampsia were reported. Case 1 was a 25-year-old primipara in the 10th month of pregnancy, and Case 2 was a 36-year-old primipara in the 9th month of pregnancy. Both were brought to our hospital because of attacks of preeclampsia and eclampsia. On admission, they were in a comatose state. Computed tomography (CT) on admission showed low- and high-density areas in the basal ganglia regions in Case 1 and low-density areas in the same regions in Case 2. In Case 1, cerebral angiograms obtained two days after the attack showed diffuse cerebral vasospasms in the anterior and middle cerebral arteries of both sides and the basilar artery. In Case 2, however, cerebral angiograms obtained three days after the attack showed no abnormal findings. The patients were saved by crisis-overcoming emergency treatment and care. The neurological condition gradually improved. Repeated CT three weeks after the onset showed only a slight low-density area and a small high-density area in the left basal ganglia region in Case 1, while the low-density areas in the bilateral basal ganglia regions disappeared in Case 2. Seven weeks after the attack, cerebral angiography was again performed, but the diffuse vasospasms had disappeared. The clinical courses were good, and the patients were discharged about eight weeks after the onset, by which time their consciousness had become clear and the neurological deficits had been well overcome. Cerebrovascular disorders caused by toxemia of pregnancy is rare; when they do occur, the main lesions of the brain are edema, focal ischemia, thrombosis, and hemorrhage. They may be related to cerebral vasospasm, and subsequent ischemic changes are observed at times with eclampsia. (author)

  17. CT findings suggesting anastomotic leak and predicting the recovery period following gastric surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Ho; Kim, Jung Hoon; Shin, Cheong-Il; Kim, Se Hyung; Han, Joon Koo; Choi, Byung Ihn [Seoul National University College of Medicine, Department of Radiology, Institute of Radiation Medicine, Jongno-gu, Seoul (Korea, Republic of)

    2015-07-15

    To assess diagnostic performance of routine CT for detecting anastomotic leak after gastric surgery, and analyse the relationship between recovery period and CT findings. We included 179 patients who underwent immediate CT and fluoroscopy after gastric surgery. Two reviewers retrospectively rated the possibility of leak on CT using a five-point scale focused on predefined CT findings. They also evaluated CT findings. Patients were categorised as: Group I, leak on fluoroscopy; Group II, possible leak on CT but negative on fluoroscopy; Group III, no leak. We analysed the relationship between recovery period and group. Area under the curve for detecting leak on CT was 0.886 in R1 and 0.668 in R2 with moderate agreement (k = 0.482). Statistically common CT findings for leak included discontinuity, large amount of air-fluid and wall thickening at anastomosis site (p < 0.05). Discontinuity at anastomosis site and a large air-fluid collection were independently associated with leak (p < 0.05). The recovery period including hospitalisation and postoperative fasting period was longer in Group I than Group II or III (p < 0.05). Group II showed a longer recovery period than Group III (p < 0.05). Postoperative routine CT was useful for predicting anastomotic leak using specific findings, and for predicting length of recovery period. (orig.)

  18. CT and MRI findings of chorea associated with nonketotic hyperglycemia

    International Nuclear Information System (INIS)

    Hu Dongjin; Zhang Weidong; Wu Dingquan; Meng Lishi; Chen Jian

    2008-01-01

    Objective: To explore the imaging diagnosis of chorea associated with nonketotic hyperglycemia by describing its CT and MR findings and correlating those findings with the clinical manifestations. Methods: The imaging findings and clinical data from 6 patients with chorea associated with nonketotic hyperglycemia were retrospectively analyzed. All 6 patients had unenhanced CT scans, 1 also had MR imaging examination. Three of 6 patients had follow-up CT scans and 1 of 3 patients had follow-up MR imaging studies. Results: CT studies of all 6 patients showed unilateral or bilateral hyperdense striatum. The putamen was involved in all 6 patients, the caudate nucleus or lateral portion of the globus pallidus were involved in 5 of all 6 patients. All 3 follow-up CT studies depicted a decreased or resolved hyperdensity of the abnormal striatum. T 1 -weighted MR images in 1 patient showed the hyperintense lesions of bilateral lentiform nuclei, T 2 -weighted MR images of the patient showed the hypointense lesions of the corresponding lentiform nuclei, and its follow-up MR images depicted invariable signal intensity of T 1 -weighted and T 2 -weighted images. In all patients, the chorea resolved within 2 to 6 days after treatment of the hyperglycemia. Conclusion: The characteristic imaging findings of chorea associated with nonketotic hyperglycemia can suggest an accurate diagnosis. (authors)

  19. CT findings of benign omental lesions following abdominal cancer surgery

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Yun; Kim, Dong Won; Cho, Jin Han; Kwon, Hee Jin; Ha, Dong Ho; Oh, Jong Young [Diagnostic Radiology, Dong-A University College of Medicine, Busan (Korea, Republic of)

    2016-07-15

    The greater omentum is the largest peritoneal fold and can be the origin of primary pathologic conditions, as well as a boundary and conduit for disease processes. Most diseases involving the omentum manifest with nonspecific and overlapping features on computed tomography (CT). In particular, varying benign disease processes of traumatic, inflammatory, vascular, or systemic origin can occur in the omentum during the follow-up period after surgery for intra-abdominal malignancy. It can be challenging for radiologists due to various spectrum of CT findings. Thus, we reviewed the CT findings of various benign omental lesions after surgery for intra-abdominal malignancy.

  20. CT findings of fundal hemorrhage in subarachnoid hemorrhage

    International Nuclear Information System (INIS)

    Munemoto, Shigeru; Ishiguro, Shuzo; Kimura, Akira; Futami, Kazuya; Kogure, Yuzaburo; Wakamatsu, Koichi; Demachi, Hiroshi

    1987-01-01

    The patient was a 66-year-old man. He lost consciousness as a result of a third subarachnoid hemorrhage attack. On neurological examination, he was found to be comatose and to have no spontaneous respiration. A mydriasis was noticed on both eyes. Bilateral retinal bleeding was also observed, with the bleeding of the left side more severe than that of the right side. After his death, his brain and eyes were examined by means of a CT scan. The CT films showed a severe subarachnoid hemorrhage and ventricular hematoma. The thin-sliced CT films showed left retinal bleeding. Retinal bleeding may be caused by a subarachnoid hemorrhage. Usually we make a sketch of the retinal bleeding on the basis of a doctor's report. A photo of an optic fundus is a good record; however, taking a photo is troublesome for severely ill patients. The CT finding of retinal bleeding is gross, but a CT image is one good way to record retinal bleeding. (author)

  1. Accessory oral cavity associated with duplication of the tongue and the mandible in a newborn: a rare case of Diprosopus. Multi-row detector computed tomography diagnostic role.

    Science.gov (United States)

    Morabito, Rosa; Colonna, Michele R; Mormina, Enricomaria; Stagno d'Alcontres, Ferdinando; Salpietro, Vincenzo; Blandino, Alfredo; Longo, Marcello; Granata, Francesca

    2014-12-01

    Craniofacial duplication is a very rare malformation. The phenotype comprises a wide spectrum, ranging from partial duplication of few facial structures to complete dicephalus. We report the case of a newborn with an accessory oral cavity associated to duplication of the tongue and the mandible diagnosed by multi-row detector Computed Tomography, few days after her birth. Our case of partial craniofacial duplication can be considered as Type II of Gorlin classification or as an intermediate form between Type I and Type II of Sun classification. Our experience demonstrates that CT scan, using appropriate reconstruction algorithms, permits a detailed evaluation of the different structures in an anatomical region. Multi-row CT scan is also the more accurate diagnostic procedure for the pre-surgical evaluation of craniofacial malformations. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  2. Research on multi-spectrum detector in high-energy dual-energy X-ray imaging system

    International Nuclear Information System (INIS)

    Li Qinghua; Wang Xuewu; Li Jianmin; Kang Kejun; Li Yuanjing; Zhong Huaqiang

    2008-01-01

    The high-energy dual-energy X-ray imaging system can discriminate the material of the objects inspected, but when the objects are too thin, the discrimination becomes very difficult. This paper proposes the use of multi-spectrum detector to improve the ability to discriminate thin material, and a series of simulation were done with the Monte Carlo method. Firstly the X-ray depositions in the detectors with different thickness were calculated, and then the discrimination effects with different detector structure and parameters were calculated. The simulation results validated that using appropriate multi-spectrum detector can improve the discrimination accuracy of thin material, particularly thin high-Z material. (authors)

  3. X-ray and CT findings of costal eosinophilic granuloma

    International Nuclear Information System (INIS)

    Tu Zhanhai; Lin Zhengyu; Chen Yiguang

    2010-01-01

    Objective: To study the X-ray and CT features of costal eosinophilic granuloma for a better understanding. Methods: Eight patients with costal eosinophilic granuloma proved by surgery or biopsy were analyzed retrospectively. All patients had X-ray plain film, 6 patients had CT examination, including a case of enhanced CT scan. Results: All 8 lesions were solitary. Six lesions were in the anterior rib and 2 in the posterior rib. On X-ray, all case showed single cavity and oval lesion with clear boundary. On CT images, 5 lesions demonstrated expansile destruction of bone with cortical bone thinning, and 3 were osteolystic destruction with soft tissue mass around. On the patient with enhanced CT scan, the lesions showed a moderate and uniform enhancement. Conclusion: The X-ray and CT findings of costal eosinophilic granuloma are characteristic. (authors)

  4. Pulmonary actinomycosis: CT studies of diagnostic and post-treatment findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Su Jung; Song, Sun Wha; Bo, Seal Hwang; Park, Hyun Jin; Kim, Hyeon Sook; Kim, Ki Jun; Kim, Horrim; Park, Seog Hee [College of Medicine, the Catholic University of Korea, Uijeongbu (Korea, Republic of)

    2008-05-15

    To investigate the value of the computed tomography (CT) in the study of diagnostic and post-treatment findings of pulmonary actinomycosis. Clinical data and CT findings were retrospectively analyzed in 10 patients with histopathologically confirmed pulmonary actinomycosis. We analyzed the initial CT findings in search of patterns and distributions which suggest possible lung abnormalities and found the pleura, chest wall, and lymphadenopathy to be involved as part of the indicators of lung abnormalities. We analyzed follow-up CT findings for changes in the lungs after antibiotic therapy and recurrence after surgery. Of the 10 patients analyzed by CT for lung lesions, seven had been diagnosed with alcoholism and nine were male. The initial CTs (n = 10) indicated that all the pulmonary lesions were solitary without chest wall involvement. However, a transfissural extension was observed in 20% of the study population (n = 2). Furthermore, peripheral lung distribution and adjacent pleural thickening was observed in 70% of the study population (n = 7). Within the consolidation (n = 6) or mass (n = 4), a central low density with peripheral enhancement was seen in 70% of the study population (n = 7). A follow-up CT of the seven cases following antiobiotic therapy revealed that four cases showed minimal improvement or aggravation of their lung lesions, whereas three cases showed resolution or improvement. The improvement of the central low density was related to the improvement of consolidation or mass. Furthermore the presence of fibrosis was observed after the resolution of pulmonary lesions (n = 2). No relationship was found between the duration and response of antibiotic therapy. A follow-up CT (n = 4) subsequent to a lung resection revealed the onset of chest wall actinomycosis and a thickened pleura in one case. The results of this study highlight the value of the CT in pulmonary actinomycosis in order to diagnose and evaluate antibiotic responses, complications, or

  5. Bubble-like appearances are characteristic thin-section CT findings of adenocarcinoma

    International Nuclear Information System (INIS)

    Kojima, Yoko; Saito, Haruhiro; Ito, Hiroyuki

    2008-01-01

    Adenocarcinomas are often diagnosed as old inflammatory lesions which are sometimes overlooked. Some of these adenocarcinomas display characteristic thin-section computed tomography (TS-CT) findings. We reported on these bubble-like appearances (BLA). We studied the BLA characteristics of adenocarcinomas. We reviewed the TS-CT findings of 17 (6 men, 11 women) cases of adenocarcinoma with bubble-like appearances. All 17 patients had undergone surgery between August 2003 and March 2007. We studied correlations between the TS-CT findings, the pathological findings and the clinical characteristics. The average tumor diameter was 35.4 mm. The definition of BLA is; having a irregular shape with straight margins, peripheral ground-glass opacity (GGO), dilated air bronchograms (more than 3), prominent pleural indentation. The pathological characteristics of tumors with BLA were; peripheral bronchioloalveolar cell carcinoma (BAC) patterns, almost total collapse (about 80% of the tumor area), and several ectatic small bronchi. Six cases were initially overlooked, because the TS-CT findings appeared as old inflammation. The average tumor doubling time was 1167 days. After resection, there have been no recurrences. On TS-CT images, BLA type adenocarcinomas appear as irregular in shape and they have a very slow doubling time. These types of lesions require careful attention because they are often diagnosed as old inflammatory scarring. (author)

  6. CT findings of traumatic primary brain-stem injury

    International Nuclear Information System (INIS)

    Hosaka, Yasuaki; Hatashita, Shizuo; Bandou, Kuniaki; Ueki, Yasuyuki; Abe, Kouzou; Koga, Nobunori; Sugimura, Jun; Sakakibara, Tokiwa; Takagi, Suguru

    1984-01-01

    A series of 27 consecutive patients with traumatic primary brain stem injuries was studied. They were diagnosed by means of clinical signs, neurological examination, and computerized tomography (CT). The CT findings of the brain-stem lesions were classified into 4 types: Type H, spotty, high-density; Type H and L, high- and low-densities; Type L, low-density; Type I, isodensity. The Glasgow coma scale (GCS), neurological findings on admission, CT findings (findings in the brain stem, obliteration of perimesencephalic cistern (PMC), and other findings), and the Glasgow outcome scale (GOS) were examined. In the 9 cases of Type H, there was a correlation between the GCS and the GOS, and the spotty, high-density lesions were localized mainly in the dorsal and/or ventral midbrain parenchyma, but these lesions did not show focal signs and symptoms. Without an obliteration of the PMC, Type-H patients did not always have a bad outcome. In the 4 cases of Type H and L, the 2 cases of Type L, and the 12 cases of Type I, there was an obliteration of the PMC. All of the these cases had a bad outcome (1 case of moderate disability, 3 cases of severe disability, and 14 cases of death). The mechanism producing a spotty, high-density area was discussed. The weaker impact (than the other types) and individual anatomical differences weresupposed to make for a spotty, high-density are in the brain stem. (author)

  7. A case of suspected 'Bickerstaff's encephalitis' and its CT findings

    International Nuclear Information System (INIS)

    Moto, Atsufumi; Endo, Shunro; Ohmori, Tomoaki; Oka, Nobuo; Takaku, Akira

    1985-01-01

    A case of suspected ''Bickerstaff's encephalitis'' was presented with special reference to the CT findings. A 4-year-old girl exhibited fever and nausea after the beginning of December, 1983, followed by unsteady gait on January 1, 1984. She was admitted to another hospital and diagnosed by means of a spinalfluid examination as having aseptic meningitis. Her symptoms subsided transiently, but then she began again to suffer recurrently from unsteady gait on January 27. After that she developed dysarthria and dysphagia, a disturbance of eye movement was observed, and she became lethargic and disoriented. On February 6, she was transferred to our hospital. Plain CT scan on admission revealed a low-density area on the left cerebellar peduncle and the inferior medial part of the left temporal lobe. Moreover, the low-density area was heterogenously enhanced with the contrast medium. Angiography showed no abnormal findings. Considering these CT findings, we suspected a pontine tumor. Four days after her admission, however, her symptoms and signs began rapidly to subside, and also the abnormal findings on the CT scan diminished gradually as the symptoms were relieved. On March 2, she was discharged without any neurological abnormality. (author)

  8. CT findings of hepatoblastoma before and after chemotherapy : correlation with pathologic features

    International Nuclear Information System (INIS)

    Seo, Joon Beom; Kim, Woo Sun; Kim, In One; Jang, Ja June; Kim, Chong Jai; Ahn, Hyo Seop; Yeon, Kyung Mo

    1998-01-01

    The purpose of this study was to analyze the CT findings of hepatoblastoma before and after chemotherapy, and to compare them with surgical and pathologic features. Twelve hepatoblastoma patients underwent chemotherapy prior to surgery; in all cases, CT scanning was performed before and after chemotherapy. We reviewed the findings with special attention to changes in tumor volume, the extent and pattern of contrast enhancement, the extent of low-attenuation area in the tumor, the presence of a septum, and calcification or ossification or ossification within the mass before and after chemotherapy. Post-chemotherapy CT findings were compared with operative and pathologic findings. After chemotheapy, the volume of the tumor mass decreased in all patients, and the extent of involved segments decreased in nine (75%), the non-enhancing area within the mass, on the other hand, increased in nine (75 %). On pre-chemotherapy CT, calcifications were detected in seven patients (58%), and on post-chemotherapy CT, in nine (75%); the extent of calcification were detected in seven patients. On the basis of CT findings, viable tumor and necrosis areas could not be distinguished. Massive calcification or osteoid mixed with loose connective tissue was noted in the mesenchymal component of the tumor; the whirling pattern of enhancement within the area of low density seen on CT scanning corresponded to osteoid mixed with loose connective tissue, which contained rich blood vessels. We describe the CT findings of hepatoblastoma both before and after chemotherapy, highlighting the changes which occurred. An understanding of these changes is helpful for the proper management of this condition. (author). 18 refs., 1 tab., 5 figs

  9. CT findings of laryngeal tuberculosis : comparison with laryngeal carcinoma

    International Nuclear Information System (INIS)

    Kim, Man Deuk; Kim, Dong Ik; Lee, Byung Hee; Sung, Ki Joon; Jung, Tae Sub; Cho, Jae Min; Yune, Heun Yune; Kim, Sun Yong

    1996-01-01

    To determine the value of CT(Computerized Tomography) in the diagnosis of laryngeal tuberculosis and to assess to what extent its characteristic findings different from those of laryngeal carcinoma. CT scans of twelve patients with laryngeal tuberculosis were reviewed and compared with those of fifteen patients with laryngeal cancer, retrospectively. Clinical symptoms, laryngoscopic examinations and the presence of pulmonary tuberculosis chest radiographs were also reviewed. In laryngeal tuberculosis, bilateral symmetric or asymmetric involvement was noted in nine(75%) patients, while unilateral involvement was seen in three(25%). This was significantly different from laryngeal cancer in which unilateral involvement was noted in twelve patients(80%). Diffuse thickening of the free margin of the epiglottis was a characteristic and frequent finding in tuberculosis(n=6, 50%). No deep submucosal infiltration of preepiglottic and paralaryngeal fat spaces is seen in tuberculosis in spite of large areas of involvement of laryngeal mucosa, while twelve patients(80%) with laryngeal cancer showed thickened deep infiltration which resulted in a submucosal mass. CT was useful in the diagnosis of laryngeal tuberculosis and its CT findings were characterized by bilateral involvement, thickening of the free margin of the epiglottis and good preservation of preepiglottic and paralaryngeal fat spaces in spite of large areas of involvement

  10. Noninvasive evaluation of cerebral arteriovenous malformations by 4D-CT angiography using 320-detector row CT

    International Nuclear Information System (INIS)

    Tajiri, H.; Jin, L.; Tsukiyama, M.; Suzuki, Y.; Sekine, S.; Shimizu, T.; Ohiwa, T.

    2012-01-01

    Full text: Objective: Four-dimensional computed tomography angiography (4D-CTA) is a new and promising technique in the diagnosis of patients with cerebral arteriovenous malformations (AVMs). The purpose of this retrospective study was to investigate the utility of 4D-CTA using whole-brain 320-detector row CT for assessing cerebral AVMs compared with conventional angiography (CA). Materials and methods: Participants included patients admitted to our institution from November 2010 to March 2012 due to cerebral AVMs who underwent both 4D-CTA and CA within 14 days. The diagnosis of AVM was finally confirmed by CA. Two readers reviewed 4D-CTA and CA under consensus regarding AVM detection rate and each component of the AVM (feeders, nidi, drainers) using a four-point grading scale (excellent=3, good=2, fair=1, poor=0), and the Spetzler-Martin (S-M) grade. Results: During the study period, 11 patients met the inclusion criteria. The average score for feeders, nidi, and drainers was 2.0, 2.3, and 2.5 in 4D-CTA and 2.4, 2.6, and 2.7 in CA, respectively. The average S-M grade score was 2.0 in all patients. There were no statistically significant differences between the two modalities (P<.005). Conclusion: 4D-CTA using 320-detector row CT is a very reliable method and offers diagnostic performance equivalent to CA for detecting and predicting S-M classification of cerebral AVMs.

  11. Nontuberculous Mycobacterial (NTM) Disease in Immunocompetent Patients: Expanding Image Findings on Chest CT

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hyo Hyun; Seon, Hyun Ju; Kim, Mok Hee; Choi, Song; Song, Sang Gook; Shin, Sang Soo; Kim, Yun Hyeon; Park, Jin Gyoon [Chonnam National University Hospital, Gwangju (Korea, Republic of)

    2010-04-15

    The aim of this study was to evaluate the chest CT features of nontuberculous mycobacterial (NTM) disease regardless of the specific organisms. This study included 74 consecutive patients (35 men, 39 women; mean age, 63 years; age range, 25-89 years) who were diagnosed with NTM disease according to the American Thoracic Society Guidelines (1997 and 2007) between January 2005 and July 2007. Chest CT images were randomly reviewed by two radiologists with consensus. The most common organism associated with NTM disease is M. avium-intracellulare complex (87.8%), followed by M. abscesses, M. kansasii, and M. chelonae. The most common chest CT finding was a nodular bronchiectatic lesion (n = 35, 46.7%), followed by a cavitary lesion of the upper lobe (n = 21, 28.0%), combined lesions of two prior subtypes (n = 6, 8.0%), consolidative lesion (s) (n = 5, 6.7%), a bronchogenic spreading pulmonary tuberculosis-like lesion (n = 5, 6.7%), a cavitary mass lesion with small satellite nodules (n = 2, 2.7%), and a miliary nodular lesion (n = 1, 1.3%). More than 5 segments were involved in 60 cases (81.1%). The nodular bronchiectatic lesion or cavitary lesion of upper lobe presents with multi-segmental involvement and the occurrence of combined consolidation is indicative of NTM disease

  12. Value of multi-slice spiral CT MPVR reconstruction in the diagnosis of acute appendicitis

    International Nuclear Information System (INIS)

    Wang Kang; Zhao Zehua; Wang Zhi; Wang Weizhong; Xu Songsen; Zhang Miao; Liu Wenjin; Zhang Guozhen; Feng Dianxu

    2005-01-01

    Objective: To investigate the value of multi-slice spiral CT MPVR reconstruction in the diagnosis of acute appendicitis. Methods: A total of 39 patients with clinically suspected acute appendicitis underwent surgery from February, 2002 to September, 2003. They were prospectively examined before surgery with routine CT scanning and MPVR reconstruction spiral CT. 31 cases of appendicitis were confirmed after appendectomy. CT scans and surgery-pathology reports were evaluated on a five-grade scale from hyperemic-edematous appendix to abscess (normal appendix: 0 grade). Results: The results of spiral CT MPVR reconstruction were compared with the surgical and pathologic findings at appendectomy, yielding an accuracy of 87.2%, sensitivity of 90.3%, specificity of 75%, positive predictive value of 93.3%, and negative predictive value of 66.7%, respectively. Results of routine CT yielded an accuracy of 38.5%, sensitivity of 38.7%, specificity of 37.5%, positive predictive value of 70.6%, and negative predictive value of 13.6%, respectively. MPVR reconstruction signs of 28 patients with acute appendicitis included enlarged appendix ( > 6 mm) (96.4%), appendicoliths (26.7%), caecal apical thickening (36.7%), periappendiceal inflammation (71.4%), and abscess (10.7%). Conclusion: The use of spiral CT MPVR reconstruction in patients with equivocal clinical presentation suspected of having acute appendicitis can lead to a significant improvement in the preoperative diagnosis and maybe a decrease in surgical-pathologic severity of appendiceal disease. (authors)

  13. Preliminary application of 320-detector spiral CT with ECG editing for assessing coronary artery in-stent restenosis

    International Nuclear Information System (INIS)

    Li Zhiming; Tan Lilian; Li Shuxin; Fu Xi; He Weihong; Liu Ke; Huang Yong; Yu Lin

    2011-01-01

    Objective: To determine the value of 320-detector spiral CT with retrospective ECG gating and editing software for detecting coronary artery in-stent restenosis. Methods: CT scans of 14 patients with coronary artery stnets were retrospectively analyzed. The examinations were performed using a 320-detector spiral CT scanner and retrospective ECG gating combined with ECG editing software. The image quality of reconstructed coronary artery in-stents was compared before and after the editing of synchronously recorded ECG. The paired-sample t test was used for statistical analysis. Results: Before ECG editing, arrhythmia and in-stent artifact resulted in image blurring, missing arterial segments, significant stepladder artifacts or non-visualization of the interior of stents. Of 14 cases before ECG editing, in-stent restenosis was detected in 10 and patency in 3. The coronary artery stent and distal bifurcation were delineated in one patient. After ECG editing, the image quality of coronary artery stents was improved with detection of in-stent restenosis (4 cases) including the one case that not evaluable before ECG editing. The average image quality score before ECG editing (2.14±0.86) was significantly (P<0.001) lower than that after ECG editing (3.07±0.73). Conclusion: Retrospective ECG gating combined with ECG editing of 320-detector spiral CT can reduce the artifacts produced by arrhythmia or in-stent swings and improve the imaging quality of coronary artery stents. (authors)

  14. CT, MRI, and FDG PET/CT findings of sinonasal sarcoma: Differentiation from squamous cell carcinoma

    International Nuclear Information System (INIS)

    Kim, Jin Ho; Yoon, Dae Young; Baek, Sora; Park, Min Woo; Kwon, Kee Hwan; Rho, Young Soo

    2016-01-01

    To evaluate computed tomography (CT), magnetic resonance imaging (MRI), and 18F-fluorodeoxyglucose (FDG) positron emission tomography/CT (PET/CT) findings for the differentiation of sinonasal sarcoma from squamous cell carcinoma (SCC). We retrospectively reviewed CT, MRI, and FDG PET/CT results in 20 patients with pathologically proven sinonasal sarcoma (n = 7) and SCC (n = 13). Imaging characteristics of tumors, such as the shape, size, margin, MRI signal intensity, pattern of enhancement, local tumor invasion, and maximum standardized uptake value (SUVmax) were analyzed and compared between sarcoma and SCC. The SUVmax of sarcomas (7.4 ± 2.1) was significantly lower than the SUVmax of the SCCs (14.3 ± 4.5) (p = 0.0013). However, no significant difference in the shape, size, margin, MRI signal intensity, pattern of enhancement, and local tumor invasion was observed between sarcoma and SCC. Although CT and MR imaging features are nonspecific, FDG PET/CT is useful in distinguishing between sinonasal sarcoma and SCC based on the SUVmax value

  15. CT, MRI, and FDG PET/CT findings of sinonasal sarcoma: Differentiation from squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Ho; Yoon, Dae Young; Baek, Sora; Park, Min Woo; Kwon, Kee Hwan; Rho, Young Soo [Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of)

    2016-07-15

    To evaluate computed tomography (CT), magnetic resonance imaging (MRI), and 18F-fluorodeoxyglucose (FDG) positron emission tomography/CT (PET/CT) findings for the differentiation of sinonasal sarcoma from squamous cell carcinoma (SCC). We retrospectively reviewed CT, MRI, and FDG PET/CT results in 20 patients with pathologically proven sinonasal sarcoma (n = 7) and SCC (n = 13). Imaging characteristics of tumors, such as the shape, size, margin, MRI signal intensity, pattern of enhancement, local tumor invasion, and maximum standardized uptake value (SUVmax) were analyzed and compared between sarcoma and SCC. The SUVmax of sarcomas (7.4 ± 2.1) was significantly lower than the SUVmax of the SCCs (14.3 ± 4.5) (p = 0.0013). However, no significant difference in the shape, size, margin, MRI signal intensity, pattern of enhancement, and local tumor invasion was observed between sarcoma and SCC. Although CT and MR imaging features are nonspecific, FDG PET/CT is useful in distinguishing between sinonasal sarcoma and SCC based on the SUVmax value.

  16. Muscular involvement by malignant lymphoma: CT and MR findings

    International Nuclear Information System (INIS)

    Kim, Baek Hyun

    2000-01-01

    To investigate the CT and MR findings of muscular involvement by malignant lymphoma. Thirteen patients with biopsy-proved muscular involvement by malignant lymphoma were included in this study. Two patients were primary muscle lymphoma and 11 patients were muscle lymphoma by secondary involvement of malignant lymphoma. CT of 10 patients (6 pre-contrast CT and 9 postcontrast CT) and MRI of 6 patients (all with pre a nd post-contrast studies) were retrospectively analyzed. In the majority of patients (84.6%, 11/13), the appearance of muscular involvement was the diffuse enlargement of several muscles as like as a group. The muscles involved by malignant lymphoma showed iso-attenuation (5/6) and homogeneity (6/6) on pre-contrast CT scan, and high attenuation (5/9) or iso-attenuation (4/9) and homogeneity (7/9) on post-contrast CT scan. The signal intensity of involved muscle showed slightly hyper- (4/6) or iso-intense (2/6) and homogeneous (6/6) on T1-weighted images, and hyper-intense (6/6) and homogeneous (4/6) on T2- and Gadolinium-enhanced T1-weighted images. Adjacent bone change was demonstrated in 69.2% (9/13), subcutaneous fat change in 61.5% (8/13), and neurovascular encasement within involved muscle in 53.8% (7/13). The CT and MR findings of muscular involvement by malignant lymphoma were diffuse enlargement of several muscles with homogeneous attenuation or signal intensity, and frequent changes in adjacent bones and subcutaneous fat, or neurovascular encasement. (author)

  17. Multi-layer cube sampling for liver boundary detection in PET-CT images.

    Science.gov (United States)

    Liu, Xinxin; Yang, Jian; Song, Shuang; Song, Hong; Ai, Danni; Zhu, Jianjun; Jiang, Yurong; Wang, Yongtian

    2018-06-01

    Liver metabolic information is considered as a crucial diagnostic marker for the diagnosis of fever of unknown origin, and liver recognition is the basis of automatic diagnosis of metabolic information extraction. However, the poor quality of PET and CT images is a challenge for information extraction and target recognition in PET-CT images. The existing detection method cannot meet the requirement of liver recognition in PET-CT images, which is the key problem in the big data analysis of PET-CT images. A novel texture feature descriptor called multi-layer cube sampling (MLCS) is developed for liver boundary detection in low-dose CT and PET images. The cube sampling feature is proposed for extracting more texture information, which uses a bi-centric voxel strategy. Neighbour voxels are divided into three regions by the centre voxel and the reference voxel in the histogram, and the voxel distribution information is statistically classified as texture feature. Multi-layer texture features are also used to improve the ability and adaptability of target recognition in volume data. The proposed feature is tested on the PET and CT images for liver boundary detection. For the liver in the volume data, mean detection rate (DR) and mean error rate (ER) reached 95.15 and 7.81% in low-quality PET images, and 83.10 and 21.08% in low-contrast CT images. The experimental results demonstrated that the proposed method is effective and robust for liver boundary detection.

  18. Indeterminate findings on oncologic PET/CT: What difference dose PET/MRI make?

    Energy Technology Data Exchange (ETDEWEB)

    Fraum, Tyler J.; Fowler, Kathryn J.; McConathy, Jonathan; Dehdashti, Farokh [Mallinckrodt Institute of Radiology, Washington University School of Medicine, Saint Louis (United States)

    2016-12-15

    Positron emission tomography/computed tomography (PET/CT) with 2-deoxy-2-[{sup 18}F]fluoro-D-glucose (FDG) has become the standard of care for the initial staging and subsequent treatment response assessment of many different malignancies. Despite this success, PET/CT is often supplemented by MRI to improve assessment of local tumor invasion and to facilitate detection of lesions in organs with high background FDG uptake. Consequently, PET/MRI has the potential to expand the clinical value of PET examinations by increasing reader certainty and reducing the need for subsequent imaging. This study evaluates the ability of FDG-PET/MRI to clarify findings initially deemed indeterminate on clinical FDG-PET/CT studies. A total of 190 oncology patients underwent whole-body PET/CT, immediately followed by PET/MRI utilizing the same FDG administration. Each PET/CT was interpreted by our institution's nuclear medicine service as a standard-of-care clinical examination. Review of these PET/CT reports identified 31 patients (16 %) with indeterminate findings. Two readers evaluated all 31 PET/CT studies, followed by the corresponding PET/MRI studies. A consensus was reached for each case, and changes in interpretation directly resulting from PET/MRI review were recorded. Interpretations were then correlated with follow-up imaging, pathology results, and other diagnostic studies. In 18 of 31 cases with indeterminate findings on PET/CT, PET/MRI resulted in a more definitive interpretation by facilitating the differentiation of infection/inflammation from malignancy (15/18), the accurate localization of FDG-avid lesions (2/18), and the characterization of incidental non-FDG-avid solid organ lesions (1/18). Explanations for improved reader certainty with PET/MRI included the superior soft tissue contrast of MRI and the ability to assess cellular density with diffusion-weighted imaging. The majority (12/18) of such cases had an appropriate standard of reference; in all 12 cases

  19. Indeterminate findings on oncologic PET/CT: What difference dose PET/MRI make?

    International Nuclear Information System (INIS)

    Fraum, Tyler J.; Fowler, Kathryn J.; McConathy, Jonathan; Dehdashti, Farokh

    2016-01-01

    Positron emission tomography/computed tomography (PET/CT) with 2-deoxy-2-["1"8F]fluoro-D-glucose (FDG) has become the standard of care for the initial staging and subsequent treatment response assessment of many different malignancies. Despite this success, PET/CT is often supplemented by MRI to improve assessment of local tumor invasion and to facilitate detection of lesions in organs with high background FDG uptake. Consequently, PET/MRI has the potential to expand the clinical value of PET examinations by increasing reader certainty and reducing the need for subsequent imaging. This study evaluates the ability of FDG-PET/MRI to clarify findings initially deemed indeterminate on clinical FDG-PET/CT studies. A total of 190 oncology patients underwent whole-body PET/CT, immediately followed by PET/MRI utilizing the same FDG administration. Each PET/CT was interpreted by our institution's nuclear medicine service as a standard-of-care clinical examination. Review of these PET/CT reports identified 31 patients (16 %) with indeterminate findings. Two readers evaluated all 31 PET/CT studies, followed by the corresponding PET/MRI studies. A consensus was reached for each case, and changes in interpretation directly resulting from PET/MRI review were recorded. Interpretations were then correlated with follow-up imaging, pathology results, and other diagnostic studies. In 18 of 31 cases with indeterminate findings on PET/CT, PET/MRI resulted in a more definitive interpretation by facilitating the differentiation of infection/inflammation from malignancy (15/18), the accurate localization of FDG-avid lesions (2/18), and the characterization of incidental non-FDG-avid solid organ lesions (1/18). Explanations for improved reader certainty with PET/MRI included the superior soft tissue contrast of MRI and the ability to assess cellular density with diffusion-weighted imaging. The majority (12/18) of such cases had an appropriate standard of reference; in all 12 cases, the

  20. Concepts for dose determination in flat-detector CT

    International Nuclear Information System (INIS)

    Kyriakou, Yiannis; Deak, Paul; Langner, Oliver; Kalender, Willi A

    2008-01-01

    Flat-detector computed tomography (FD-CT) scanners provide large irradiation fields of typically 200 mm in the cranio-caudal direction. In consequence, dose assessment according to the current definition of the computed tomography dose index CTDI L=100mm , where L is the integration length, would demand larger ionization chambers and phantoms which do not appear practical. We investigated the usefulness of the CTDI concept and practical dosimetry approaches for FD-CT by measurements and Monte Carlo (MC) simulations. An MC simulation tool (ImpactMC, VAMP GmbH, Erlangen, Germany) was used to assess the dose characteristics and was calibrated with measurements of air kerma. For validation purposes measurements were performed on an Axiom Artis C-arm system (Siemens Medical Solutions, Forchheim, Germany) equipped with a flat detector of 40 cm x 30 cm. The dose was assessed for 70 kV and 125 kV in cylindrical PMMA phantoms of 160 mm and 320 mm diameter with a varying phantom length from 150 to 900 mm. MC simulation results were compared to the values obtained with a calibrated ionization chambers of 100 mm and 250 mm length and to thermoluminesence (TLD) dose profiles. The MCs simulations were used to calculate the efficiency of the CTDI L determination with respect to the desired CTDI ∞ . Both the MC simulation results and the dose distributions obtained by MC simulation were in very good agreement with the CTDI measurements and with the reference TLD profiles, respectively, to within 5%. Standard CTDI phantoms which have a z-extent of 150 mm underestimate the dose at the center by up to 55%, whereas a z-extent of ≥600 mm appears to be sufficient for FD-CT; the baseline value of the respective profile was within 1% to the reference baseline. As expected, the measurements with ionization chambers of 100 mm and 250 mm offer a limited accuracy, whereas an increased integration length of ≥600 mm appeared to be necessary to approximate CTDI ∞ in within 1%. MC

  1. The value of brain CT findings in acute methanol toxicity

    International Nuclear Information System (INIS)

    Taheri, Morteza Sanei; Moghaddam, Hossein Hassanian; Moharamzad, Yashar; Dadgari, Shahrzad; Nahvi, Vahideh

    2010-01-01

    Objective: Due to depressant effects of methanol on the central nervous system, brain computed tomography (CT) scan has been introduced as a diagnostic device in methanol intoxication. The authors aimed to present brain CT findings in patients with acute methanol intoxication and to determine signs associated with death. Materials and methods: This cohort study involved 42 consecutive patients with acute methanol intoxication. Inclusion criteria were consisted of characteristic clinical presentation of methanol poisoning, and metabolic acidosis with increased anion and osmolar gaps. Brain CT scans without contrast medium were obtained. To determine the association between the CT findings and death, the chi-square test or the Fisher's exact test, odds ratio (OR) and its 95% confidence interval (95% CI) were calculated. Results: Twenty-eight patients (66.6%) had a total of 55 abnormal findings on brain CT, in which bilateral putaminal hypodense lesions was the most common manifestation (27 cases, 96.4%). Putaminal hemorrhage with varying degrees was observed in 7 patients (25%). Six patients (21.4%) had low attenuation lesions in the subcortical white matter of the insula. A significant association was observed between putaminal hemorrhage (OR = 8, 95% CI = 1.187-53.93, P = 0.018) and subcortical necrosis of the insula (OR = 11, 95% CI = 1.504-80.426, P = 0.007) with death. Conclusion: In addition to clinical and laboratory findings, presence of putaminal hemorrhage and insular subcortex white matter necrosis are associated with a poor clinical outcome in patients with methanol poisoning.

  2. CT findings of pulmonary mucosa-associated lymphoid tissue lymphoma

    International Nuclear Information System (INIS)

    Zhang Weidong; Guan Yubao; Li Chuanxing; Wu Peihong

    2010-01-01

    Objective: To study the CT findings of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma. Methods: The CT examinations of 12 patients with pathologically proven pulmonary MALT lymphoma were reviewed retrospectively. Evaluated imaging findings included number, distribution, shape, attenuation and other associated findings of each lesion were evaluated. Results: Thirty-two pulmonary lesions, including consolidations, masses, nodules and lesions with ground glass attenuation, were identified in 12 patients. Multiple lesions were founded in 10 of 12 patients and solitary lesion in 2 patients. Multiple lesions found in one lung in 2 patients, and multiple lesions found in both lungs in 8 patients. Ten cases demonstrated 21 consolidation lesions with air bronchogram, and one of the ten cases demonstrated two lesions with airway dilatation. Three cases demonstrated 5 masses or nodular lesions, 3 of these 5 lesions showed air bronchogram. Two cases demonstrated 6 ground glass attenuation lesions. One case showed mediastinal and hilar lymphadenopathy. Conclusion: Pulmonary MALT lymphoma usually appears as multiple bilateral consolidations, masses, nodules with air bronchogram or lesions with ground- glass attenuation at CT imaging. The imaging findings described above and with an indolent clinical course may suggest the diagnosis of pulmonary MALT lymphoma. (authors)

  3. CT diagnosis of peritoneal metastasis tumor

    International Nuclear Information System (INIS)

    Deng Xueying; Chen Xiaoqi; Qi Le; Huang Feng

    2005-01-01

    Objective: To study the CT findings and diagnosis of peritoneal metastasis. Methods: The CT findings of 17 cases with surgical- pathologically proved peritoneal metastasis were analyzed retrospectively. Results The CT findings of peritoneal metastasis included: (1)ascites (12 cases ); (2)the aternation of parietal peritoneum including broad band thickening (7 cases), nodular sign (2 cases), and massive thickening (1 cases); (3) the involved omentum and mesenterium: 'smut' appearances (7 cases), nodular sign (2 cases), 'omental cake' (5 cases); (4) the invlovement of mesenteric vessels; (5) single-or multi-cystic lesions within peritoneum (1 case) . Conclusion: CT scan is the first choice for metastasis of peritoneum. (authors)

  4. CT findings of traumatic posterior hip dislocation after reduction

    International Nuclear Information System (INIS)

    Moon, Sung Kyoung; Park, Ji Seon; Ryu, Kyung Nam; Jin, Wook; Jin Wook

    2008-01-01

    To evaluate the CT images of reduced hips after posterior hip dislocation and to propose specific diagnostic criteria based on the CT results. We retrospectively reviewed the CT findings on 18 reduced hips from 17 patients with radiographs and clinical histories of traumatic posterior hip dislocations by evaluating 18 corresponding CT scans for joint space asymmetry, intra-articular abnormalities (intra-articular fat obliteration, loose bodies, and joint effusion), changes in posterior soft tissue (capsule, muscles, and adjacent fat), the presence, and location of fractures (acetabulum and femoral head). All 18 hips (100%) showed posterior soft tissue changes. In total, 17 hips (94.4%) had intra-articular abnormalities and 15 hips (83.3%) had joint space asymmetries. In addition, 17 hips (94.4%) had fractures involving the acetabula (15 cases, 88.2%) the femoral head (13 cases, 76.5%), or on both sides (11 cases, 64.7%). The most frequent fracture location was in he posterior wall (13/15, 86.7%) of the acetabulum and in the anterior aspect (10/13, 76.9%) of the femoral head. Patients with a prior history of posterior hip dislocation showed specific CT findings after reduction, suggesting the possibility of previous posterior hip dislocations in patients

  5. Chest CT findings in pediatric Wegener's granulomatosis

    Energy Technology Data Exchange (ETDEWEB)

    Levine, Daniel [British Columbia Children' s Hospital, Department of Radiology and Nuclear Medicine, Vancouver, British Columbia (Canada); Akikusa, Jonathan [Royal Children' s Hospital Melbourne, Department of Rheumatology, Melbourne (Australia); Manson, David [Hospital for Sick Children, Department of Radiology, Toronto (Canada); Silverman, Earl; Schneider, Rayfel [Hospital for Sick Children, Department of Rheumatology, Toronto (Canada)

    2007-01-15

    Although pulmonary involvement occurs in the majority of children and adolescents with Wegener's granulomatosis (WG), relatively little has been published regarding the CT imaging manifestations in this group of patients. To determine the frequency and types of chest CT abnormalities in active pediatric WG (pWG). The study was a retrospective examination of 29 chest CT examinations performed at diagnosis (n=14) and during disease flares (n=15) in 18 children. The most common abnormalities were nodules (seen in 90% of examinations), ground-glass opacification (52%), and air-space opacification (45%). Of examinations with nodules, 73% demonstrated nodules >5 mm in diameter and 69% demonstrated more than five nodules; 17% had cavitary lesions. The only abnormality with a significant difference in prevalence between diagnosis and disease flares was air-space opacification, present in 71% and 20%, respectively (P < 0.01). In accordance with the findings of published adult studies and at variance with those of prior pediatric studies, our findings indicate that chest CT abnormalities in active pWG are frequent, most commonly comprising nodules and ground-glass opacification, which may be difficult to detect on plain radiography. We therefore advocate the routine use of chest CT for all affected patients, both at the time of presentation and during disease flares. (orig.)

  6. Tuberculous adenitis: comparison of CT and MRI findings with histopathological features

    International Nuclear Information System (INIS)

    Backer, A.I. de; Mortele, K.J.; Heuvel, E. van den; Vanschoubroeck, I.J.; Kockx, M.M.; Vyvere, M. van de

    2007-01-01

    Our aim was to investigate the relationship between the various histopathological features and the CT and MRI findings in routinely submitted histopathological specimens for the diagnosis of tuberculous lymphadenopathy. Twelve formalin-fixed, paraffin-embedded tissue blocks from ten patients who were clinically suspected of having tuberculous lymphadenopathy were evaluated. We assessed the presence of histopathological features including granuloma formation, caseous necrosis, and presence of Langhans-type giant cells, calcifications, fibrosis or normal lymphoid tissue. We performed polymerase chain reaction (PCR)-based assay for mycobacterial DNA and Ziehl-Neelsen staining for acid-fast bacilli (AFB). Findings were compared with those of CT and MRI, including signal intensities on unenhanced MR images, lymph node homogeneity, attenuation values on contrast-enhanced CT and enhancement patterns on MRI. Based on CT and MRI findings, four lymph node types could be defined: (1) homogeneous nodes, visible on both pre- and post-contrast images and corresponding histopathologically to granulation tissue without or with minimal caseation necrosis (n = 2); (2) heterogeneous nodes, showing heterogeneous enhancement patterns with central non-enhancing areas and corresponding to minor or moderate intranodal caseation/liquefaction necrosis (n = 3); (3) nodes showing peripheral rim enhancement and corresponding to moderate or extensive intranodal caseation/liquefaction necrosis (n = 5); (4) heterogeneous nodes showing intranodal hyperdensities on CT and hypointense areas on T1- and T2-weighted images and corresponding to fibrosis and calcifications (n = 2). On CT and MRI, the findings reflect different stages of the tuberculous process. Imaging findings depend on the presence and the degree of granuloma formation, caseation/liquefaction necrosis, fibrosis and calcifications. (orig.)

  7. Is hepatotropic contrast enhanced MR a more effective method in differential diagnosis of hemangioma than multi-phase CT and unenhanced MR?

    Directory of Open Access Journals (Sweden)

    Markiet Karolina

    2011-04-01

    Full Text Available Abstract Background Cavernous hemangiomas are the most frequent neoplasms of the liver and in routine clinical practice they often need to be differentiated from malignant tumors and other benign focal lesions. The purpose of this study is to evaluate whether diagnostic accuracy of magnetic resonance imaging (MRI of hepatic hemangiomas, showing atypical pattern on US, improves with the use of Gd-BOPTA in comparison with contrast-enhanced multi-phase computed tomography (CT. Methods 178 consecutive patients with ambiguous hepatic masses showing atypical hyperechoic pattern on grey-scale US, underwent unenhanced and contrast-enhanced multi-phase multi-detector CT and MR (1.5T with the use of liver-specific contrast medium gadobenate dimeglumine (Gd-BOPTA. After intravenous contrast administration arterial (HAP, venous-portal (PVP, equilibrium phases (EP both in CT and MR and additionally hepatobiliary phase (HBP in MR were obtained. 398 lesions have been detected including 99 hemangiomas and 299 other lesions. Results In non-enhanced MDCT examination detection of hemangiomas was characterized by sensitivity of 76%, specificity of 90%, PPV of 71%, NPV of 92% and accuracy of 86%. Non-enhanced MR examination showed sensitivity of 98%, specificity of 99%, PPV of 99%, NPV of 99% and accuracy of 99%. After intravenous administration of contrast medium in MR the mentioned above parameters did not increase significantly. Conclusion Gd-BOPTA-enhanced MR in comparison with unenhanced MRI does not improve diagnostic accuracy in discriminating hemangiomas that show non-specific appearance in ultrasound examination. Unenhanced MR as a method of choice should directly follow US in course of diagnostic algorithm in differentiation of hemangiomas from other liver tumors.

  8. CT and MRI normal findings

    International Nuclear Information System (INIS)

    Moeller, T.B.; Reif, E.

    1998-01-01

    This book gives answers to questions frequently heard especially from trainees and doctors not specialising in the field of radiology: Is that a normal finding? How do I decide? What are the objective criteria? The information presented is three-fold. The normal findings of the usual CT and MRI examinations are shown with high-quality pictures serving as a reference, with inscribed important additional information on measures, angles and other criteria describing the normal conditions. These criteria are further explained and evaluated in accompanying texts which also teach the systematic approach for individual picture analysis, and include a check list of major aspects, as a didactic guide for learning. The book is primarily intended for students, radiographers, radiology trainees and doctors from other medical fields, but radiology specialists will also find useful details of help in special cases. (orig./CB) [de

  9. Quantification of myocardial blood flow using dynamic 320-row multi-detector CT as compared with ¹⁵O-H₂O PET.

    Science.gov (United States)

    Kikuchi, Yasuka; Oyama-Manabe, Noriko; Naya, Masanao; Manabe, Osamu; Tomiyama, Yuuki; Sasaki, Tsukasa; Katoh, Chietsugu; Kudo, Kohsuke; Tamaki, Nagara; Shirato, Hiroki

    2014-07-01

    This study introduces a method to calculate myocardium blood flow (MBF) and coronary flow reserve (CFR) using the relatively low-dose dynamic 320-row multi-detector computed tomography (MDCT), validates the method against (15)O-H₂O positron-emission tomography (PET) and assesses the CFRs of coronary artery disease (CAD) patients. Thirty-two subjects underwent both dynamic CT perfusion (CTP) and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group), the calculation method for MBF and CFR was established. In the other 13 normal subjects (validation group), MBF and CFR obtained by dynamic CTP and PET were compared. Finally, the CFRs obtained by dynamic CTP and PET were compared between the validation group and CAD patients (n = 7). Correlation between MBF of MDCT and PET was strong (r = 0.95, P dynamic CTP and PET (r = 0.67, P = 0.0126). CFRCT in the CAD group (2.3 ± 0.8) was significantly lower than that in the validation group (5.2 ± 1.8) (P = 0.0011). We established a method for measuring MBF and CFR with the relatively low-dose dynamic MDCT. Lower CFR was well demonstrated in CAD patients by dynamic CTP. • MBF and CFR can be calculated using dynamic CTP with 320-row MDCT. • MBF and CFR showed good correlation between dynamic CTP and PET. • Lower CFR was well demonstrated in CAD patients by dynamic CTP.

  10. Transient acute tubular dysfunction in the newborn: CT findings

    International Nuclear Information System (INIS)

    McLaughlin, M.G.; Schwartz, J.R.; Swayne, L.C.; Columbia Univ., New York; Rubenstein, J.B.; University of Medicine and Dentistry of New Jersey, Newark, NJ; Block, D.C.

    1990-01-01

    We report the CT and sonographic findings of transient acute tubular disease in a newborn infant, who was dehydrated at birth. The initial CT scan demonstrated focal areas of increased attenuation within the central portions of both kidneys, and sonography showed echogenic medullary pyramids. After adequate hydration, a follow-up examination demonstrated complete spontaneous resolution. (orig.)

  11. CT findings of rectosigmoid carcinoma showing exophytic growth

    International Nuclear Information System (INIS)

    Ohgi, Kazuyuki; Kohno, Atsushi; Higuchi, Mutsumi

    1987-01-01

    CT findings of 7 rectosigmoid carcinomas showing exophytic growth were evaluated. All cases had bulky masses, ranging from 6.0 to 11.5 cm in maximum diameter. All masses were difficult to differentiate from the other pelvic masses on CT, presumably due to their exophytic growth and/or invasion to the surrounding organs. However, 3 out of 7 cases showed diffuse rectosigmoidal wall thickening adjacent to the primary tumor, and it is considered to be valuable in the determination of primary site. All female cases had gynecological symptom such as genital bleeding, due to uterine and/or vaginal invasion. When indeterminate pelvic mass is revealed by CT, rectosigmoid carcinoma should be considered into differential diagnosis. (author)

  12. Prevalence of incidental or unexpected findings on low-dose CT performed during routine SPECT/CT nuclear medicine studies

    International Nuclear Information System (INIS)

    Yap, Kelvin Kwok-Ho; Sutherland, Tom; Shafik-Eid, Raymond; Taubman, Kim; Schlicht, Stephen; Ramaseshan, Ganeshan

    2015-01-01

    In nuclear medicine, single-photon-emission computed tomography (SPECT) is often combined with ‘simultaneous’ low-dose CT (LDCT) to provide complementary anatomical and functional correlation. As a consequence, numerous incidental and unexpected findings may be detected on LDCT. Recognition of these findings and appropriate determination of their relevance can add to the utility of SPECT/CT. We aimed to evaluate the prevalence and categorise the relevance of incidental and unexpected findings on LDCT scans performed as part of routine SPECT/CT studies. All available LDCT scans performed as part of SPECT/CT studies at St. Vincent's Hospital Melbourne in the year 2013 were retrospectively reviewed. Two qualified radiologists independently reviewed the studies and any previous available imaging and categorised any detected incidental findings. A total of 2447 LDCT studies were reviewed. The relevance of the findings was classified according to a modified version of a scale used in the Colonography Reporting and Data System: E1 = normal or normal variant (28.0%); E2 = clinically unimportant (63.5%); E3 = likely unimportant or incompletely characterised (6.2%); E4 = potentially important (2.5%). Imaging specialists need to be cognisant of incidental and unexpected findings present on LDCT studies performed as part of SPECT/CT. Appropriate categorisation of findings and communication of potentially important findings to referring clinicians should form part of routine practice. The overall prevalence of potentially significant incidental and unexpected findings in our series was 8.7% (E3, 6.2%; E4, 2.5%) and was comparable to rates in other published imaging series.

  13. High-quality 3D correction of ring and radiant artifacts in flat panel detector-based cone beam volume CT imaging

    Science.gov (United States)

    Abu Anas, Emran Mohammad; Kim, Jae Gon; Lee, Soo Yeol; Kamrul Hasan, Md

    2011-10-01

    The use of an x-ray flat panel detector is increasingly becoming popular in 3D cone beam volume CT machines. Due to the deficient semiconductor array manufacturing process, the cone beam projection data are often corrupted by different types of abnormalities, which cause severe ring and radiant artifacts in a cone beam reconstruction image, and as a result, the diagnostic image quality is degraded. In this paper, a novel technique is presented for the correction of error in the 2D cone beam projections due to abnormalities often observed in 2D x-ray flat panel detectors. Template images are derived from the responses of the detector pixels using their statistical properties and then an effective non-causal derivative-based detection algorithm in 2D space is presented for the detection of defective and mis-calibrated detector elements separately. An image inpainting-based 3D correction scheme is proposed for the estimation of responses of defective detector elements, and the responses of the mis-calibrated detector elements are corrected using the normalization technique. For real-time implementation, a simplification of the proposed off-line method is also suggested. Finally, the proposed algorithms are tested using different real cone beam volume CT images and the experimental results demonstrate that the proposed methods can effectively remove ring and radiant artifacts from cone beam volume CT images compared to other reported techniques in the literature.

  14. High-quality 3D correction of ring and radiant artifacts in flat panel detector-based cone beam volume CT imaging

    International Nuclear Information System (INIS)

    Anas, Emran Mohammad Abu; Hasan, Md Kamrul; Kim, Jae Gon; Lee, Soo Yeol

    2011-01-01

    The use of an x-ray flat panel detector is increasingly becoming popular in 3D cone beam volume CT machines. Due to the deficient semiconductor array manufacturing process, the cone beam projection data are often corrupted by different types of abnormalities, which cause severe ring and radiant artifacts in a cone beam reconstruction image, and as a result, the diagnostic image quality is degraded. In this paper, a novel technique is presented for the correction of error in the 2D cone beam projections due to abnormalities often observed in 2D x-ray flat panel detectors. Template images are derived from the responses of the detector pixels using their statistical properties and then an effective non-causal derivative-based detection algorithm in 2D space is presented for the detection of defective and mis-calibrated detector elements separately. An image inpainting-based 3D correction scheme is proposed for the estimation of responses of defective detector elements, and the responses of the mis-calibrated detector elements are corrected using the normalization technique. For real-time implementation, a simplification of the proposed off-line method is also suggested. Finally, the proposed algorithms are tested using different real cone beam volume CT images and the experimental results demonstrate that the proposed methods can effectively remove ring and radiant artifacts from cone beam volume CT images compared to other reported techniques in the literature.

  15. Multi-detector CT findings of primary tubercular appendicitis: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Il Young; Kim, Shin Young; Park, Ji Sang; Kim, Sang Won; Cho, Hyun Deuk; Shin, Hyeong Cheol [Soonchunhyang University Cheonan Hospital, Cheonan (Korea, Republic of)

    2008-07-15

    The frequency of intestinal tuberculosis is relatively common; however, primary tuberculosis of the appendix remains a rarity. We report on a case of primary tuberculous appendicitis for which we obtained the MDCT images revealing thickening of the appendix and the surrounding lymphadenopathies.

  16. 2-D response mapping of multi-linear silicon drift detectors

    International Nuclear Information System (INIS)

    Castoldi, A.; Guazzoni, C.; Hartmann, R.; Mezza, D.; Strueder, L.; Tassan Garofolo, F.

    2010-01-01

    Multi-linear silicon drift detectors (MLSDDs) are good candidates to fulfill simultaneous requirements for 2-D position-sensing and spectroscopy applications. The optimization of their design and performance as 2-D imagers requires a detailed study of timing properties of the charge cloud in the MLSDD architecture. In particular it is important to experimentally determine the dependence of the measured amplitude and time-of-arrival on the photon position of interaction so as to derive the 2D detector response. In this paper we will present a detailed experimental characterization aimed at measuring the detector amplitude response and its timing response. The dependence of charge cloud drift time on precise position of interaction has been measured as a function of detector biasing conditions.

  17. Temporal bone trauma: correlative study between CT findings and clinical manifestations

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Hee; Kim, Hyung Jin; Kim, Jae Hyoung [College of Medicine, Gyeongsang National University, Jinju (Korea, Republic of)

    1994-11-15

    To assess how accurately computed tomography (CT) can demonstrate the abnormal findings which are believed to cause the clinical signs and symptoms of hearing loss (HL), vertigo and facial paralysis (FP) in patients with temporal bone trauma. The authors studied CT scans of 39 ears in 35 patients with temporal bone trauma. CT scans were performed with 1-1.5 mm slice thickness and table incrementation. Both axial and coronal scans were obtained in 32 patients and in three patients only axial scans were obtained. We analyzed CT with special reference to the structural abnormalities of the external auditory canal, middle ear cavity, bony labyrinth, and facial nerve canal, and correlated these findings with the actual clinical signs and symptoms. As to hearing loss, we evaluated 32 ears in which pure tone audiometry or brainstem evoked response audiometry had been performed. With respect to the specific types of HL, CT accurately showed the abnormalities in 84% (16/19) in conductive HL, 100% (2/2) in sensorineural HL, and 25% (2/8) for mixed HL. When we categorized HL simply as conductive and sensorineural, assuming that mixed be the result of combined conductive and sensorineural HL, CT demonstrated the abnormalities in 89% (24/27) for conductive HL and 50% (5/10) for sensorineural HL. Concerning vertigo and FP, CT demonstrated abnormalities in 67%(4/6), and 29% (4/14), respectively. Except for conductive HL, CT seems to have a variable degree of limitation for the demonstration of the structural abnormalities resulting sensorineural HL, vertigo or facial paralysis. It is imperative to correlate the CT findings with the signs and symptoms in those clinical settings.

  18. Temporal bone trauma: correlative study between CT findings and clinical manifestations

    International Nuclear Information System (INIS)

    Kim, Jung Hee; Kim, Hyung Jin; Kim, Jae Hyoung

    1994-01-01

    To assess how accurately computed tomography (CT) can demonstrate the abnormal findings which are believed to cause the clinical signs and symptoms of hearing loss (HL), vertigo and facial paralysis (FP) in patients with temporal bone trauma. The authors studied CT scans of 39 ears in 35 patients with temporal bone trauma. CT scans were performed with 1-1.5 mm slice thickness and table incrementation. Both axial and coronal scans were obtained in 32 patients and in three patients only axial scans were obtained. We analyzed CT with special reference to the structural abnormalities of the external auditory canal, middle ear cavity, bony labyrinth, and facial nerve canal, and correlated these findings with the actual clinical signs and symptoms. As to hearing loss, we evaluated 32 ears in which pure tone audiometry or brainstem evoked response audiometry had been performed. With respect to the specific types of HL, CT accurately showed the abnormalities in 84% (16/19) in conductive HL, 100% (2/2) in sensorineural HL, and 25% (2/8) for mixed HL. When we categorized HL simply as conductive and sensorineural, assuming that mixed be the result of combined conductive and sensorineural HL, CT demonstrated the abnormalities in 89% (24/27) for conductive HL and 50% (5/10) for sensorineural HL. Concerning vertigo and FP, CT demonstrated abnormalities in 67%(4/6), and 29% (4/14), respectively. Except for conductive HL, CT seems to have a variable degree of limitation for the demonstration of the structural abnormalities resulting sensorineural HL, vertigo or facial paralysis. It is imperative to correlate the CT findings with the signs and symptoms in those clinical settings

  19. The Multi-Purpose Detector (MPD) of the collider experiment

    Energy Technology Data Exchange (ETDEWEB)

    Golovatyuk, V.; Kekelidze, V.; Kolesnikov, V.; Rogachevsky, O. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Sorin, A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Nuclear University (MEPhI), Moscow (Russian Federation)

    2016-08-15

    The project NICA (Nuclotron-based Ion Collider fAcility) is aimed to study dense baryonic matter in heavy-ion collisions in the energy range up to √(s{sub NN}) = 11 GeV with average luminosity of L = 10{sup 27} cm{sup -2}s{sup -1} (for {sup 197}Au{sup 79}). The experimental program at the NICA collider will be performed with the Multi-Purpose Detector (MPD). We report on the main physics objectives of the NICA heavy-ion program and present the main detector components. (orig.)

  20. Chest CT findings in breast cancer patients treated with postoperative irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Yeon Joo; Kim, Kun Il; Lee, Suk Hong; Kim, Dong Won; Bae, Yeong Tae [College of Medicine, Pusan National Univ., Pusan (Korea, Republic of)

    2002-07-01

    The determine the chest CT findings in breast cancer patients who have undergone postoperative irradiation. The chest CT findings in 36 female patients who underwent breast surgery and radiotherapy between May 1996 and March 2000 were rerospectively analysed. Prior to radiotheraphy, baseline chest CT depicted normal parenchyma in all cases. In 11 patients, the ipsilateral breast and chest wall were irradiated using opposed tangential fields, while 25 were treated by the four fields method (opposed tangential fields plus anterior and posterior supraclavicular/high axillary fields), with a total dose of 5040-5400 cGy for 5-9 weeks. CT after radiotherapy demonstrated reticular opacity (n=24), perpendicular linear opacity (n=15), traction bronchiectasis (n=7), consolidation (n=6), ground glass attenuation (n=3), pathologic rib fractures (n=3) pleural effusion (n=2), and pleural thickening (n=1), while in five patients no abnormality was observed. in addition, in the anterolateral lung area of 23 (64%) of 36 patients who underwent tangential beam irradiation, CT demonstrated peripheral opacities. When supraclavicular and axillary portals were used, radiation-induced lung changes mostly occurred at the apex of the lung (n=24). Chest radiographs were abnormal in 26 patients and normal in ten; in five of these ten, CT demonstrated reticular opacity. Depending on the irradiation CT findings of radiation-induced lung injury in breast cancer include areas of increased opacity with or without fibrosis, in apical and/or anterior subpleural regions. CT may help differentiate radiation-induced parenchymal change from superimposed or combined lung disease.

  1. Rhabdomyosarcoma of children in the head and neck : CT and MR finding

    International Nuclear Information System (INIS)

    Park, Byung Kwan; Kim, In One; Kim, Woo Sun; Han, Sang Wook; Kim, Hyun Beom; Yeon, Myung Mo

    1998-01-01

    The purpose of this study is to evaluate radiologic findings of rhabdomyosarcoma of children in the head and neck concerning the origin, morphologic characteristics, extent, and the route of intracranial extension on CT and MR. Twenty cases of pathologically proven rhabdomyosarcoma were analyzed. Fifteen CT scans (postcontrast CT (n=13), precontrast CT (n=2)) and eleven MR scans were obtained. Postcontrast MR scans were performed in the ten cases. Six cases had CT and MR scans. Nine cases had only CT scan and five had only MR scans. We retrospectively analyzed the origin, morphologic characteristics (attenuation, signal intensity, margin), extent,intracranial extension, route and clinical staging of rhabdomyosarcoma on CT and MR scans. Rhabdomyosarcoma of children in the head and neck tends to show relatively severe bony destruction of skull base and various intracranial extension routes can be helpful radiologic findings on the CT or MR scan although its CT density or signal intensity of MR was not specific. And it is peculiar that infratempral fossa was the most common site of origin of rhabdomyosarcoma. (author). 28 refs., 2 tabs., 5 figs

  2. FDG PET/CT for therapeutic response monitoring in multi-site non-respiratory tuberculosis

    International Nuclear Information System (INIS)

    Geng Tian; Yong Xiao; Bin Chen; Jun Xia; Hong Guan; Qunyi Deng

    2010-01-01

    Background: Tuberculosis (TB) can produce positive signals during 18 F-fluorodeoxyglucose positron emission/computed tomography (FDG PET/CT) scanning. Until now, there has been no better method than clinical assessment to evaluate the therapeutic response of non-respiratory TB (NRTB). Purpose: To retrospectively assess the ability of FDG PET/CT to evaluate the response to anti-TB treatment in patients with NRTB. Material and Methods: Three patients with multi-site NRTB underwent repeat PET/CT scans during anti-TB treatment. Changes in maximal standard uptake value (SUVmax) of the TB lesions on PET/CT images were analyzed between two scans. Initial PET/CT scans were performed before the start of anti-TB treatment, and later scans were performed after completion of the treatment. Results: Patient 1, a 63-year-old female, and patient 2, a 50-year-old male, were diagnosed as multi-site NRTB by biopsy. Patient 3, a 37-year-old male was diagnosed clinically. These patients demonstrated multiple FDG-avid lesions in whole body on initial PET/CT images. The highest SUVmax of patient 1, 2, and 3 were 13.6, 17.7, and 13.9 separately. After completion of the treatment, all positive signals of patient 1, 2, and 3 decreased to undetectable value on repeated PET/CT scans with intervals of 318 days, 258 days, and 182 days separately. Conclusion: FDG PET/CT scan may be useful for monitoring responses to anti-TB treatment in patients with NRTB

  3. CT findings of adenocarcinoma of the lung

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, T. J.; Kim, S. J.; Lee, D. Y.; Ahn, C. M [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-03-01

    To evaluate CT findings of primary adenocarcinoma of the lung and to assess distant metastasis at the time of diagnosis. CT findings of 150 patients with adenocarcinoma, confirmed by histopathologic methods, were classified as central or peripheral lesion and pattern analysis of typical findings noted in this cancer was carried out. Intra and extrathoracic metastases of adenocarcinoma were also investigated. Of 150 cases of adenocarcinoma of the lung, 121 were found to be of the peripheral type and 29 were of the central type. These peripheral lesions comprised 105 nodules, 11 consolidations, four cavities and one linear lesion, while the central lesions consisted of 19 cases of atelectasis and tens of branchial wall thickening. lung to lung(nine cases), lymphangitic(five cases), and pleural metastasis(16 cases) were presented as intrathoracic metastasis, while bone(17), brain,(six), liver(two) and adrenal metastasis(one case)were presented as extrathoracic metastasis. The most common radiologic finding of adenocarcinoma is a peripheral single mass or nodule but consolidation, cavity or tubular lesions, as well as atelectasis or bronchial wall thickening alone can be presented as unusual findings of adenocarcinoma. As a consequence, it is in many cases difficult to differentially diagnose. Distant metastasis was also noted in many cases of early T-stage lesion, so to successfully manage the patient, careful evaluation of the metastasis is essential.

  4. CT findings of adenocarcinoma of the lung

    International Nuclear Information System (INIS)

    Jeon, T. J.; Kim, S. J.; Lee, D. Y.; Ahn, C. M

    1996-01-01

    To evaluate CT findings of primary adenocarcinoma of the lung and to assess distant metastasis at the time of diagnosis. CT findings of 150 patients with adenocarcinoma, confirmed by histopathologic methods, were classified as central or peripheral lesion and pattern analysis of typical findings noted in this cancer was carried out. Intra and extrathoracic metastases of adenocarcinoma were also investigated. Of 150 cases of adenocarcinoma of the lung, 121 were found to be of the peripheral type and 29 were of the central type. These peripheral lesions comprised 105 nodules, 11 consolidations, four cavities and one linear lesion, while the central lesions consisted of 19 cases of atelectasis and tens of branchial wall thickening. lung to lung(nine cases), lymphangitic(five cases), and pleural metastasis(16 cases) were presented as intrathoracic metastasis, while bone(17), brain,(six), liver(two) and adrenal metastasis(one case)were presented as extrathoracic metastasis. The most common radiologic finding of adenocarcinoma is a peripheral single mass or nodule but consolidation, cavity or tubular lesions, as well as atelectasis or bronchial wall thickening alone can be presented as unusual findings of adenocarcinoma. As a consequence, it is in many cases difficult to differentially diagnose. Distant metastasis was also noted in many cases of early T-stage lesion, so to successfully manage the patient, careful evaluation of the metastasis is essential

  5. An Anomaly Detector Based on Multi-aperture Mapping for Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    LI Min

    2016-10-01

    Full Text Available Considering the correlationship of spectral content between anomaly and clutter background, inaccurate selection of background pixels induced estimation error of background model. In order to solve the above problems, a multi-aperture mapping based anomaly detector was proposed in this paper. Firstly, differing from background model which focused on feature extraction of background, multi-aperture mapping of hyperspectral data characterized the feature of whole hyperspectral data. According to constructed basis set of multi-aperture mapping, anomaly salience index of every test pixel was proposed to measure the relative statistic difference. Secondly, in order to analysis the moderate salience anomaly precisely, membership value was constructed to identify anomaly salience of test pixels continuously based on fuzzy logical theory. At same time, weighted iterative estimation of multi-aperture mapping was expected to converge adaptively with membership value as weight. Thirdly, classical defuzzification was proposed to fuse different detection results. Hyperspectral data was used in the experiments, and the robustness and sensitivity to anomaly with lower silence of proposed detector were tested.

  6. CT cystography

    International Nuclear Information System (INIS)

    Tsili, A.

    2012-01-01

    Full text: Cancer of the urinary bladder is one of the commonest urothelial neoplasms. Conventional cystoscopy remains the mainstay in the diagnosis of urinary bladder carcinomas. But it is an invasive and uncomfortable procedure, associated with complications. Computed tomographic (CT) virtual cystoscopy has been proposed as an alternative imaging modality with potential advantages in the detection of urinary bladder neoplasms and good patient acceptance. It is a minimally invasive technique, allowing imaging of the urinary bladder in multiple planes and a 360 0 view. CT cystoscopy provides information about the location, size and morphologic features of urinary bladder lesions, indicating appropriate areas for biopsy. It can be performed in cases in which conventional cystoscopy is not feasible, such as in the presence of urethral strictures, marked prostatic hypertrophy or active bleeding, and in cases in which cystoscopic findings are inconclusive. The technique can be used to evaluate areas of the urinary bladder difficult to evaluate with cystoscopy, such as the anterior bladder neck and narrowmouthed diverticula. Finally, virtual cystoscopy provides both intraluminal and extraluminal pathologic changes, so intravesical disease and exrtavesical extension can be evaluated in the same study. One of the limitations of this technique is the difficulty to demonstrate small-sized lesions. The introduction of multi-detector row CT (MDCT) scanners was a major technological advancement because among other things it substantially improves z-axis resolution by reducing section collimation and allowing the detection of very small lesions. The near isotropic or isotropic pixels achieved with a multidetector CT scanner, enable the creation of multiplanar reformatted images with a resolution very close to that of the axial images and three-dimensional (3D) renderings of outstanding quality. Transverse, multiplanar reformations and virtual endoscopic images are complementary

  7. CT scan findings of fungal pneumonia; Diagnose der Pilzpneumonie in der Thorax-CT

    Energy Technology Data Exchange (ETDEWEB)

    Heckmann, M.; Uder, M.; Bautz, W.; Heinrich, M. [Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. fuer Diagnostische Radiologie

    2008-07-01

    The importance of fungal infection of the lung in immunocompromised patients has increased substantially during the last decades. Numerically the most patients are those with neutropenia, e.g. patients with malignancies or solid organ and stem cell transplantation, chemotherapy, corticosteroid use and HIV infection. Although fungal infections can occur in immunocompetent patients, their frequency in this population is rare. The clinical symptoms such as fever accompanied with non-productive cough are unspecific. In some patients progression to hypoxemia and dyspnea may occur rapidly. In spite of improved antifungal therapy morbidity and mortality of these infections are still high. Therefore an early and non-invasive diagnosis is very important. That is why CT and even better High-Resolution-CT (HR-CT) is a very important modality in examining immunocompromised patients with a probability of fungal infection. CT is everywhere available and, as a non-invasive method, able to give the relevant diagnose efficiently. This paper should give an overview about the radiologic findings and possible differential diagnosis of diverse pulmonary fungal infections in CT. Pneumonias caused by Aspergillus, Cryptococcus, Candida, Histoplasma, Mucor and Geotrichum capitatum are illustrated. (orig.)

  8. Peripheral pulmonary arteries: identification at multi-slice spiral CT with 3D reconstruction

    International Nuclear Information System (INIS)

    Coche, Emmanuel; Pawlak, Sebastien; Dechambre, Stephane; Maldague, Baudouin

    2003-01-01

    Our objective was to analyze the peripheral pulmonary arteries using thin-collimation multi-slice spiral CT. Twenty consecutive patients underwent enhanced-spiral multi-slice CT using 1-mm collimation. Two observers analyzed the pulmonary arteries by consensus on a workstation. Each artery was identified on axial and 3D shaded-surface display reconstruction images. Each subsegmental artery was measured at a mediastinal window setting and compared with anatomical classifications. The location and branching of every subsegmental artery was recorded. The number of well-visualized sub-subsegmental arteries at a mediastinal window setting was compared with those visualized at a lung window setting. Of 800 subsegmental arteries, 769 (96%) were correctly visualized and 123 accessory subsegmental arteries were identified using the mediastinal window setting. One thousand ninety-two of 2019 sub-subsegmental arteries (54%) identified using the lung window setting were correctly visualized using the mediastinal window setting. Enhanced multi-slice spiral CT with thin collimation can be used to analyze precisely the subsegmental pulmonary arteries and may identify even more distal pulmonary arteries. (orig.)

  9. CT and MRI findings of Madelung syndrome

    International Nuclear Information System (INIS)

    Liu Changhua; Zeng Yinglang; Zou Donglu; Wu Guihua

    2011-01-01

    Objective: To determine the CT and MR findings of Madelung syndrome. Methods: Five cases of Madelung syndrome were collected in our hospital from February 2006 to June 2009, including 3 cases of type Ⅰ Madelung syndrome and 2 cases of type Ⅱ Madelung syndrome. The 5 cases were all examined by CT, meanwhile 1 case by CT enhancement scanning and 2 cases by MR. The clinical characteristics and imaging manifestations were analyzed. Results: CT and MR images in 3 patients of type Ⅰ Madelung syndrome displayed fat accumulation within the subcutaneous tissue of the upper trunk and deep layer tissue of neck. The diffuse masses were located around the neck, upper chest and shoulders, which were called 'horse collar' and 'buffalo hump'. The other 2 cases of type Ⅱ Madelung syndrome displayed fat thickening within the subcutaneous tissue of the proximal extremities, anterior chest wall, showing special appearance of 'vigorous sailor'. All the 5 patients showed fat deposit within the subcutaneous tissue of the anterior rectus abdominis, inguina and fat accumulation within the scrotum. CT showed proliferated fat at the subcutaneous tissue of the involved regions. The CT value of proliferated fat were between - 30 and -70 HU. The proliferated fat tissue all could be displayed on MR T 1 WI, T 2 WI and T 2 WI fat suppression sequence, with typical hypointensity on T 1 WI and hyperintensity on T 2 WI, hypointensity on fat-suppression sequence and fibrous septation presenting among fat tissue. Conclusion: Combination with the history of long-term alcohol abuse, the Madelung syndrome could be diagnosed by CT and MR, which had great value in the surgical planning for identifying the extent of disease. (authors)

  10. Tuberculous otitis media: findings on high-resolution CT

    International Nuclear Information System (INIS)

    Lungenschmid, D.; Buchberger, W.; Schoen, G.; Schoepf, R.; Mihatsch, T.; Birbamer, G.; Wicke, K.

    1993-01-01

    We describe two cases of tuberculous otitis media studied with high-resolution computed tomography (CT). Findings included extensive soft tissue densities with fluid levels in the tympanic cavity, the antrum, the mastoid and petrous air cells. Multifocal bony erosions and reactive bone sclerosis were seen as well. CT proved valuable for planning therapy by accurately displaying the involvement of the various structures of the middle and inner ear. However, the specific nature of the disease could only be presumed. (orig.)

  11. CT findings of esophageal schwannoma: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Man Ho; Ryu, Dae Shick; Eom, Dae Woon; Shin, Dong Rock; Choi, Soo Jung; Ahn, Jae Hong; Park, Man Soo; Yoo, Dong Kon [Gangneung Asan Hospital, College of Medicine, University of Ulsan, Gangneung (Korea, Republic of)

    2015-03-15

    Esophageal schwannomas are a relative rare benign neoplasm that usually occurs in the upper esophagus, in the middle aged women. We report a case of a 67-year-old man with a lower esophageal schwannoma. This lesion was composed of homogenous density, iso-attenuating with the chest wall muscle on pre- and post-contrast chest computed tomography (CT). The CT findings of the esophageal schwannoma are similar to those of esophageal leiomyoma. Hense, esophageal schwannoma may be a differential diagnosis with esophageal leiomyoma.

  12. CT scan findings and EEG in systemic lupus erythematodes patients with neuro-psychiatric disorders

    Energy Technology Data Exchange (ETDEWEB)

    Kan, Rumiko; Hagiwara, Mariko; Katayose, Keiko; Yashima, Yuko; Kumashiro, Hisashi

    1988-06-01

    In 14 patients with systemic lupus erythematodes presenting with neuro-psychiatric disorders, CT scans were compared with encephalographic (EEG) findings. CT findings were markedly abnormal in 6, slight with a sulcal enlargement in 3, and normal in 5. In the group of markedly abnormal CT findings, focal abnormal low density areas were detected in 2, severe generalized cerebral atrophy in one, and severe atrophy of the right hemisphere in one. EEG findings included focal paroxysmal abnormality of high voltage slow burst at the left frontal dominance and positive spike on the right hemisphere. Epileptic seizure and depressed sensorium seemed to be related to CT abnormality. In 3 patients with epileptic seizures, their symptoms were closely related to CT abnormality. Parkinsonisms and depressed sensorium were also related to CT abnormality. (Namekawa, K).

  13. CT scan findings and EEG in systemic lupus erythematodes patients with neuro-psychiatric disorders

    International Nuclear Information System (INIS)

    Kan, Rumiko; Hagiwara, Mariko; Katayose, Keiko; Yashima, Yuko; Kumashiro, Hisashi

    1988-01-01

    In 14 patients with systemic lupus erythematodes presenting with neuro-psychiatric disorders, CT scans were compared with encephalographic (EEG) findings. CT findings were markedly abnormal in 6, slight with a sulcal enlargement in 3, and normal in 5. In the group of markedly abnormal CT findings, focal abnormal low density areas were detected in 2, severe generalized cerebral atrophy in one, and severe atrophy of the right hemisphere in one. EEG findings included focal paroxysmal abnormality of high voltage slow burst at the left frontal dominance and positive spike on the right hemisphere. Epileptic seizure and depressed sensorium seemed to be related to CT abnormality. In 3 patients with epileptic seizures, their symptoms were closely related to CT abnormality. Parkinsonisms and depressed sensorium were also related to CT abnormality. (Namekawa, K)

  14. CT findings of lumbar intervertebral disc: II. Disc herniation (HNP)

    International Nuclear Information System (INIS)

    Yang, W. J.; Lee, J. M.; Bahk, Y. W.

    1984-01-01

    In lumbar region the epidural fat pad is relatively abundant so that CT can provides sufficient information in diagnosis of lumbar HNP. Many authors have reported on the CT findings of HNP such as focal nodular protrusion of the posterior disc margin, obliteration of epidural fat pad, impingement of dural sac and nerve root, swelling of nerve root, soft tissue density in the spinal canal and calcification of disc. However there was so previous report describing incidence and reliability of the findings. It is the purpose of the present study to survey the frequency, reliability, and limitation of these CT findings. The clinical material was consisted of 30 operatively proven cases of HNP of the lumbar spine. Each lumbar CT scan was reviewed retrospectively and the findings were analysed by two radiologists independently. There were 20 males and 10 females and the mean age was 36.7 years. Involvement of L4-S5 level was 2.3 times more frequent than that of L5-S1 level. Of 30 cases, 22 were unilateral posterolateral types and 8 cases central or unilateral far lateral types. CT findings observed were nodular protrusion of the posterior margin of the disc, obliteration of epidural fat pad, impingement of dural sac or nerve root, soft tissue density in the spinal canal and calcification in the posterior portion of the protruded disc, in order of decreasing frequency. The conclusions are follows: 1. Nodular protrusion of the posterior disc margin accompanied by obliteration of epidural fat pad was observed in every case. The former findings was designated as direct sign and the latter indirect. 2. Obliteration of the epidural fat appears to be significant in lateral recesses especially when it occurs unilaterally. This was not true, however, in the centrally located fat pad. 3. Impingement of the dural sac and nerve root were observed in 90% and 67%, respectively, and were very helpful in establishing HNP diagnosis when the direct and indirect signs were equivocal

  15. Simultaneous acquisition of X-ray spectra using a multi-wire, position-sensitive gas flow detector

    International Nuclear Information System (INIS)

    Beaven, Peter A.; Marmotti, Mauro; Kampmann, Reinhard; Knoth, Joachim; Schwenke, Heinrich

    2003-01-01

    A multi-wire, gas-filled position-sensitive detector has been developed for the simultaneous recording of wavelength-dispersed X-ray signals that enables X-ray fluorescence spectrometry with a limited multi-element capability in the low Z element range. Details of the modular construction of the detector are given. The detector performance was characterized using Al-Kα radiation and a variable slit system. The detector has been applied in a laboratory spectrometer equipped with an electron source and a double multilayer mirror device as the wavelength-dispersing element. Spectra from Al and Si obtained in the simultaneous acquisition mode show good agreement with calculations performed using a ray-tracing model

  16. Thoracic Injuries in earthquake-related versus non-earthquake-related trauma patients: differentiation via Multi-detector Computed Tomography

    Directory of Open Access Journals (Sweden)

    Zhi-hui Dong

    2011-01-01

    Full Text Available PURPOSE: Massive earthquakes are harmful to humankind. This study of a historical cohort aimed to investigate the difference between earthquake-related crush thoracic traumas and thoracic traumas unrelated to earthquakes using a multi-detector Computed Tomography (CT. METHODS: We retrospectively compared an earthquake-exposed cohort of 215 thoracic trauma crush victims of the Sichuan earthquake to a cohort of 215 non-earthquake-related thoracic trauma patients, focusing on the lesions and coexisting injuries to the thoracic cage and the pulmonary parenchyma and pleura using a multi-detector CT. RESULTS: The incidence of rib fracture was elevated in the earthquake-exposed cohort (143 vs. 66 patients in the non-earthquake-exposed cohort, Risk Ratio (RR = 2.2; p<0.001. Among these patients, those with more than 3 fractured ribs (106/143 vs. 41/66 patients, RR=1.2; p<0.05 or flail chest (45/143 vs. 11/66 patients, RR=1.9; p<0.05 were more frequently seen in the earthquake cohort. Earthquake-related crush injuries more frequently resulted in bilateral rib fractures (66/143 vs. 18/66 patients, RR= 1.7; p<0.01. Additionally, the incidence of non-rib fracture was higher in the earthquake cohort (85 vs. 60 patients, RR= 1.4; p<0.01. Pulmonary parenchymal and pleural injuries were more frequently seen in earthquake-related crush injuries (117 vs. 80 patients, RR=1.5 for parenchymal and 146 vs. 74 patients, RR = 2.0 for pleural injuries; p<0.001. Non-rib fractures, pulmonary parenchymal and pleural injuries had significant positive correlation with rib fractures in these two cohorts. CONCLUSIONS: Thoracic crush traumas resulting from the earthquake were life threatening with a high incidence of bony thoracic fractures. The ribs were frequently involved in bilateral and severe types of fractures, which were accompanied by non-rib fractures, pulmonary parenchymal and pleural injuries.

  17. Isovaleric acidaemia: cranial CT and MRI findings

    International Nuclear Information System (INIS)

    Sogut, Ayhan; Acun, Ceyda; Tomsac, Nazan; Demirel, Fatma; Aydin, Kubilay; Aktuglu, Cigdem

    2004-01-01

    Isovaleric acidaemia is an inborn error of leucine metabolism due to deficiency of isovaleryl-CoA dehydrogenase, which results in accumulation of isovaleric acid in body fluids. There are acute and chronic-intermittent forms of the disease. We present the cranial CT and MRI findings of a 19-month-old girl with the chronic-intermittent form of isovaleric acidaemia. She presented with severe metabolic acidosis, hyperglycaemia, glycosuria, ketonuria and acute encephalopathy. Cranial CT revealed bilateral hypodensity of the globi pallidi. MRI showed signal changes in the globi pallidi and corticospinal tracts of the mesencephalon, which were hypointense on T1-weighted and hyperintense on T2-weighted images. (orig.)

  18. Isovaleric acidaemia: cranial CT and MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Sogut, Ayhan; Acun, Ceyda; Tomsac, Nazan; Demirel, Fatma [Department of Paediatrics, Karaelmas University, Zonguldak (Turkey); Aydin, Kubilay [Department of Radiology, Istanbul Medical School, Istanbul University, Camlikyolu, B. mehmetpasa sokak yavuz apt. No:10/10, Etiler, Istanbul (Turkey); Aktuglu, Cigdem [Department of Paediatrics, Cerrahpasa Medical School, Istanbul University, Istanbul (Turkey)

    2004-02-01

    Isovaleric acidaemia is an inborn error of leucine metabolism due to deficiency of isovaleryl-CoA dehydrogenase, which results in accumulation of isovaleric acid in body fluids. There are acute and chronic-intermittent forms of the disease. We present the cranial CT and MRI findings of a 19-month-old girl with the chronic-intermittent form of isovaleric acidaemia. She presented with severe metabolic acidosis, hyperglycaemia, glycosuria, ketonuria and acute encephalopathy. Cranial CT revealed bilateral hypodensity of the globi pallidi. MRI showed signal changes in the globi pallidi and corticospinal tracts of the mesencephalon, which were hypointense on T1-weighted and hyperintense on T2-weighted images. (orig.)

  19. CT Findings of Small Bowel Anisakiasis: Analysis of Four Cases

    International Nuclear Information System (INIS)

    Kim, Wee Kyoung; Song, Soon Young; Cho, On Koo; Koh, Byung Hee; Kim, Yong Soo; Jung, Woo Kyoung; Kim, Min Yeong

    2011-01-01

    We wanted to describe the CT findings of small bowel anisakiasis with the pathologic correlation. Four patients with surgically and pathologically proven small bowel anisakiasis were included in this retrospective study. They were three men and one woman and their ages ranged from 28 to 43 years (mean age: 38 years). We evaluated their clinical, CT and histological findings. All the patients had a history of ingesting raw fish within 24 hours from the time of symptom onset. They complained of abdominal pain (n=4), nausea (n=4), vomiting (n=2) and diarrhea (n=1). Physical examination revealed tenderness (n=4), rebound tenderness (n=4) and increased bowel sounds (n=3). Leukocytosis was noted in all the patients on the laboratory examination. None of the patients showed eosinophilia. The CT findings were segmental small bowel wall thickening with preserved layering (n=4), focal segmental luminal narrowing with proximal dilatation (n=4), peritoneal thickening (n=3), mesenteric or omental infiltration (n=4) and varying degrees of ascites (n=4). On the histopathologic examination, they revealed an infiltration of eosinophils (n=4) in all layers of the bowel wall with severe edema. The larvae were found on surgico-pathologic examination in all the cases. The CT findings may be helpful to make the specific diagnosis of small bowel anisakiasis in a patient with the clinical findings of an acute abdomen and a history of eating raw fish

  20. CT Findings of Small Bowel Anisakiasis: Analysis of Four Cases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Wee Kyoung; Song, Soon Young; Cho, On Koo; Koh, Byung Hee [Hanyang University College of Medicine, Seoul (Korea, Republic of); Kim, Yong Soo; Jung, Woo Kyoung; Kim, Min Yeong [Hanyang University Guri Hospital, College of Medicine, Guri (Korea, Republic of)

    2011-02-15

    We wanted to describe the CT findings of small bowel anisakiasis with the pathologic correlation. Four patients with surgically and pathologically proven small bowel anisakiasis were included in this retrospective study. They were three men and one woman and their ages ranged from 28 to 43 years (mean age: 38 years). We evaluated their clinical, CT and histological findings. All the patients had a history of ingesting raw fish within 24 hours from the time of symptom onset. They complained of abdominal pain (n=4), nausea (n=4), vomiting (n=2) and diarrhea (n=1). Physical examination revealed tenderness (n=4), rebound tenderness (n=4) and increased bowel sounds (n=3). Leukocytosis was noted in all the patients on the laboratory examination. None of the patients showed eosinophilia. The CT findings were segmental small bowel wall thickening with preserved layering (n=4), focal segmental luminal narrowing with proximal dilatation (n=4), peritoneal thickening (n=3), mesenteric or omental infiltration (n=4) and varying degrees of ascites (n=4). On the histopathologic examination, they revealed an infiltration of eosinophils (n=4) in all layers of the bowel wall with severe edema. The larvae were found on surgico-pathologic examination in all the cases. The CT findings may be helpful to make the specific diagnosis of small bowel anisakiasis in a patient with the clinical findings of an acute abdomen and a history of eating raw fish

  1. Castleman disease of the neck: CT and MR imaging findings

    International Nuclear Information System (INIS)

    Jiang, Xin-hua; Song, Hao-ming; Liu, Qing-yu; Cao, Yun; Li, Guo-hong; Zhang, Wei-dong

    2014-01-01

    Objective: To characterize the computed tomography (CT) and magnetic resonance imaging (MRI) findings of Castleman disease of the neck. Methods: The imaging findings of 21 patients with Castleman disease of the neck were reviewed retrospectively. Of the 21 patients, 16 underwent unenhanced and contrast-enhanced CT scans; 5 underwent unenhanced and contrast-enhanced MRI scans. Results: The unenhanced CT images showed isolated or multiple well-defined homogenous mild hypodensity lesions in fifteen cases, and a heterogeneous nodule with central areas of mild hypodensity in one case. Calcification was not observed in any of the patients. In five patients, MR T1-weighted images revealed well-defined, homogeneous isointense or mild hyperintense lesions to the muscle; T2-weighted images showed these as intermediate hyperintense. Sixteen cases showed intermediate to marked homogeneous enhancement on contrast-enhanced CT or MR T1-weighted images. Of the other five cases that underwent double-phase CT scans, four showed mild or intermediate heterogeneous enhancement at the arterial phase, and homogeneous intermediate or marked enhancement at the venous phase; the remaining case showed mild and intermediate ring-enhancement with a central non-enhanced area at the arterial and venous phases, respectively. Conclusion: Castleman disease of the neck can be characterized as solitary or multiple well-defined, mild hypodensity or homogeneous intense lesions on plain CT/MR scans, and demonstrates intermediate and marked enhancement on contrast-enhanced CT/MR scans. On double-phase CT scans, Castleman disease often demonstrates mild enhancement at the arterial phase, and gradually uniform enhancement at venous phase. Double-phase enhanced CT or MRI may help to differentiate Castleman disease from other diseases

  2. Castleman disease of the neck: CT and MR imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xin-hua [Department of Radiology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060 (China); Song, Hao-ming [Department of Cardiology, Shanghai Tongji Hospital, Shanghai 200065 (China); Liu, Qing-yu [Department of Radiology, The Second Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510120 (China); Cao, Yun [Department of Pathology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060 (China); Li, Guo-hong [Department of Radiology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060 (China); Zhang, Wei-dong, E-mail: dongw.z@163.com [Department of Radiology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060 (China)

    2014-11-15

    Objective: To characterize the computed tomography (CT) and magnetic resonance imaging (MRI) findings of Castleman disease of the neck. Methods: The imaging findings of 21 patients with Castleman disease of the neck were reviewed retrospectively. Of the 21 patients, 16 underwent unenhanced and contrast-enhanced CT scans; 5 underwent unenhanced and contrast-enhanced MRI scans. Results: The unenhanced CT images showed isolated or multiple well-defined homogenous mild hypodensity lesions in fifteen cases, and a heterogeneous nodule with central areas of mild hypodensity in one case. Calcification was not observed in any of the patients. In five patients, MR T1-weighted images revealed well-defined, homogeneous isointense or mild hyperintense lesions to the muscle; T2-weighted images showed these as intermediate hyperintense. Sixteen cases showed intermediate to marked homogeneous enhancement on contrast-enhanced CT or MR T1-weighted images. Of the other five cases that underwent double-phase CT scans, four showed mild or intermediate heterogeneous enhancement at the arterial phase, and homogeneous intermediate or marked enhancement at the venous phase; the remaining case showed mild and intermediate ring-enhancement with a central non-enhanced area at the arterial and venous phases, respectively. Conclusion: Castleman disease of the neck can be characterized as solitary or multiple well-defined, mild hypodensity or homogeneous intense lesions on plain CT/MR scans, and demonstrates intermediate and marked enhancement on contrast-enhanced CT/MR scans. On double-phase CT scans, Castleman disease often demonstrates mild enhancement at the arterial phase, and gradually uniform enhancement at venous phase. Double-phase enhanced CT or MRI may help to differentiate Castleman disease from other diseases.

  3. CT findings of plastic bronchitis in children after a Fontan operation

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    Goo, Hyun Woo [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea); Jhang, Won Kyoung; Kim, Young Hwee; Ko, Jae Kon; Park, In Sook [University of Ulsan College of Medicine, Department of Pediatric Cardiology, Asan Medical Center, Seoul (Korea); Park, Jeong-Jun; Yun, Tae-Jin; Seo, Dong-Man [University of Ulsan College of Medicine, Department of Pediatric Cardiac Surgery, Asan Medical Center, Seoul (Korea)

    2008-09-15

    Plastic bronchitis is a rare cause of acute obstructive respiratory failure in children. Life-threatening events are much more frequent in patients with repaired cyanotic congenital heart disease, and most frequent following a Fontan operation. Commonly, the diagnosis is not made until bronchial casts are expectorated. Detailed CT findings in plastic bronchitis have not been described. To describe the CT findings in plastic bronchitis in children after a Fontan operation. Three children with plastic bronchitis after a Fontan operation were evaluated by chest CT. Bronchial casts were spontaneously expectorated and/or extracted by bronchoscopy. Airway and lung abnormalities seen on CT were analyzed in the three children. CT demonstrated bronchial casts in the central airways with associated atelectasis and consolidation in all children. The affected airways were completely or partially obstructed by the bronchial casts without associated bronchiectasis. The airway and lung abnormalities rapidly improved after removal of the bronchial casts. CT can identify airway and lung abnormalities in children with plastic bronchitis after a Fontan operation. In addition, CT can be used to guide bronchoscopy and to monitor treatment responses, and thereby may improve clinical outcomes. (orig.)

  4. CNS Involvement in Hemophagocytic Lymphohistiocytosis: CT and MR Findings

    International Nuclear Information System (INIS)

    Chung, Tae Woong

    2007-01-01

    Hemophagocytic lymphohistiocytosis (HLH) is a rare disorder that is characterized by proliferation of benign histiocytes, and this commonly involves the liver, spleen, lymph nodes, bone marrow and central nervous system (CNS). We report here on the CT and MR imaging findings in a case of CNS HLH that showed multiple ring enhancing masses mimicking abscess or another mass on the CT and MR imaging. emophagocytic lymphohistiocytosis (HLH) is a rare disorder that is characterized by nonmalignant diffuse infiltration of multiple organs, including the central nervous system (CNS), by lymphocytes and histiocytes (1). Many radiologic reports describing diffuse white matter infiltrations, parenchymal atrophy and calcification have been published, but the characteristics of these findings remain non-specific, especially in immunocompromised patients. We present here a case of HLH in a 3-year-old boy who presented with multiple ring enhancing lesions involving the brain. In conclusion, although the CT and MRI findings of HLH with ring enhancing parenchymal lesions are nonspecific and mimic abscess, and especially in the immunosuppressed patients, increased diffusion at the center on DWI may be a finding of HLH to differentiate it from abscess, which has restricted diffusion at the center. However, the pathologic correlation with DWI according to the lesion stage certainly needs further study with a larger number of patients

  5. Evaluation on temporal bone CT findings of cholesteatoma

    International Nuclear Information System (INIS)

    Lee, Kun Won; Lee, Nam Joon; Kang, Eun Young; Chung, Kyoo Byung; Suh, Won Hyuck

    1989-01-01

    Cholesteatomas are thought to result from ingrowth of keratinizing squamous epithelium from external ear to middle ear. The cholesteatomas are usually diagnosed by clinical symptoms and signs, otoscopy, and plain radiograms. But various view points are emphasized radiologically before operation, leading to examine by computed tomography (CT), especially in complicated cases. We retrospectively reviewed the CT findings of cholesteatomas in 25 surgically proven cases during the period from May, 1983 to Aug, 1988. The results were as follows: 1. Most cholesteatomas showed soft tissue mass and bony erosion of ossicles (88%), attic wall and mastoid antrum (84%) on temporal bone CT scan. 2. The CT members of cholesteatomas ranged from 25 to 50 HU (avg. 33 HU). 3. Involved sites were attic (16%), antrum (28%), and both attic and antrum (56%). Other sites were middle ear cavity and external auditory canal. 4. Extra-tympanomastoid extension of cholesteatoma was intracranial abscess (8%), exposure of dural sinus (8%), and extension along with neck (4%)

  6. Contribution to data acquisition software of Eurogram and Diamant multi detectors in an Unix/VXWorks environment

    International Nuclear Information System (INIS)

    Diarra, C.

    1994-06-01

    Questions on nuclear matter, need to have new performant equipments. Eurogram is a 4 PI gamma radiations multi detector and a precious tool in gamma spectroscopy, but it is necessary to use a charged particles detector and in this aim Diamant is an Eurogram partner. These two multi detectors needed special software data acquisition systems. The whole of acquisition control and management is based on sun stations with unix system. 56 figs., 64 refs

  7. CT findings of the pulmonary tuberculosis in patients with diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chang Kyu; Hong, Deok Hwa; Kim, Yeong Tong; Kim, Hyung Lyul; Lee, Jong Myeong; Kim, Jong Kun; Lee, So Hyun; Jeong, Gun Young [Taejon Sun General Hospital, Taejon (Korea, Republic of)

    1998-07-01

    To evaluate the CT findings of pulmonary tuberculosis in patients with diabetes mellitus (MD),according to the diabetic control state. Materials and Methods: We retrospectively studied 34 cases of pulmonary tuberculosis accompanied by DM. We divided the right lung three lobes and ten segments and the left into two lobes and eight segments and analyzed CT findings of bronchogenic spread, cavitary lesion, ill-defined nodule, lobular consolidation, lobar and segmental consolidation, atelectasis, interlobular septal thickening, fibrotic band, and associated findings such as lymph node enlargement, pleural effusion and empyema. We also tried to determine the typical CT findings of pulmonary tuberculosis according to diabetic duration and controlled state of DM focusing by FBS 160 and HbA1C 8.0. Results: Among 34 CT scans, bronchogenic spread was seen on 29 (85.3%), cavitary lesion on 26 (76.5%), ill-defined nodules on 11 (32.4%), lobular consolidation on 14 (41.2%), lobar and segmental consolidation on 12 (35.3%), atelectasis on four (14.7%), and fibrotic band on eight (23.5%). Multiple cavities were present in 76.9% of total cavitary lesions, and consolidation with bronchogenic spread in 75%; associated findings were as follows: lymph node enlargement (n=1), pleural effusion (n=10), empyema (n=2), and pericardial effusion (n=2). In 46.7% of cases, general tubercular lesions were in an unusual location, but among cases of secondary pulmonary tuberculosis, 73.9% of lesions were in the usual location. More lobular consolidation was seen in patients with less than FBS 160 on admission, and this result was statistically significant (p<0.05); CT findings did not, however, differ according to diabetic duration and HbA1C. Conclusion: In patients with DM,general fubercular lesions were found infrequently, but in secondary tubereulosis, multiple cavitary lesions-in the usual location-were very frequent. In patients with DM, CT findings of pulmonary tuberculosis did not vary

  8. CT findings of the pulmonary tuberculosis in patients with diabetes mellitus

    International Nuclear Information System (INIS)

    Yang, Chang Kyu; Hong, Deok Hwa; Kim, Yeong Tong; Kim, Hyung Lyul; Lee, Jong Myeong; Kim, Jong Kun; Lee, So Hyun; Jeong, Gun Young

    1998-01-01

    To evaluate the CT findings of pulmonary tuberculosis in patients with diabetes mellitus (MD),according to the diabetic control state. Materials and Methods: We retrospectively studied 34 cases of pulmonary tuberculosis accompanied by DM. We divided the right lung three lobes and ten segments and the left into two lobes and eight segments and analyzed CT findings of bronchogenic spread, cavitary lesion, ill-defined nodule, lobular consolidation, lobar and segmental consolidation, atelectasis, interlobular septal thickening, fibrotic band, and associated findings such as lymph node enlargement, pleural effusion and empyema. We also tried to determine the typical CT findings of pulmonary tuberculosis according to diabetic duration and controlled state of DM focusing by FBS 160 and HbA1C 8.0. Results: Among 34 CT scans, bronchogenic spread was seen on 29 (85.3%), cavitary lesion on 26 (76.5%), ill-defined nodules on 11 (32.4%), lobular consolidation on 14 (41.2%), lobar and segmental consolidation on 12 (35.3%), atelectasis on four (14.7%), and fibrotic band on eight (23.5%). Multiple cavities were present in 76.9% of total cavitary lesions, and consolidation with bronchogenic spread in 75%; associated findings were as follows: lymph node enlargement (n=1), pleural effusion (n=10), empyema (n=2), and pericardial effusion (n=2). In 46.7% of cases, general tubercular lesions were in an unusual location, but among cases of secondary pulmonary tuberculosis, 73.9% of lesions were in the usual location. More lobular consolidation was seen in patients with less than FBS 160 on admission, and this result was statistically significant (p<0.05); CT findings did not, however, differ according to diabetic duration and HbA1C. Conclusion: In patients with DM,general fubercular lesions were found infrequently, but in secondary tubereulosis, multiple cavitary lesions-in the usual location-were very frequent. In patients with DM, CT findings of pulmonary tuberculosis did not vary

  9. Pneumatosis intestinalis: CT findings and clinical features

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hye Lin; Lee, Hae Kyung; Park, Seong Jin; Yi, Boem Ha; Ko, Bong Min; Hong, Hyun Sook; Paik, Sang Hyun [Soonchunhyang University Hospital Bucheon, Bucheon (Korea, Republic of)

    2008-02-15

    The purpose of this study is to evaluate the CT findings and clinical features of patients with pneumatosis intestinalis. From January 2001 to October 2007, 15 patients with pneumatosis intestinalis were diagnosed by the use of CT. We analyzed the clinical features and CT findings to assess the involvement site, the presence of portal and mesenteric vein gas, and the existence of accompanied ischemic change. Of the 15 patients, five patients had end stage renal disease (33.3%), two patients underwent a gastrectomy, one patient underwent a laminectomy, one patient had tuberculous enteritis, one patient had lung cancer and one patient had pneumonia. Four patients presented with no specific disease. There was portal or mesenteric venous gas in six cases, and strangulation or an ischemic change of the bowel in five cases. Otherwise, pneumatosis intestinalis was associated with hydropneumoperitoneum in two cases, pneumoperitoneum in one case and a single case of perforated appendicitis. Nine patients underwent surgery for ischemic change of the bowel, pneumoperitoneum, appendicitis, and a clinical sign of panperitonitis. Among the remaining six patients, three patients recovered and were discharged, and three patients expired during progression of the disease. End stage renal disease is the most common condition associated with pneumatosis intestinalis. The presence of portomesenteric venous gas, ischemic change of the bowel, and linear pneumatosis intestinalis are indicative of a poor prognosis.

  10. CT findings and differential diagnosis of cystic neck masses

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Yeon; Lee, Kil Jun; Jeong, Seong Ki; Han, Seong Nim; Tae, Seok; Shin, Kyoung Ja; Lee, Sang Chun [Seoul Red Cross Hospital, Seoul (Korea, Republic of)

    1995-10-15

    The purpose of this study is to analyze the CT features of the cystic masses in the neck and to review differential diagnosis. We retrospectively reviewed and analyzed the CT findings of 22 histopathologically proved, cystic neck masses in regard to the location in fascial plane and relationship with adjacent organ. Of 22 cases, ten congenital cysts two ranulas, seven inflammatory lesions, and three solid tumors were included. Ten congenital cystic masses were located in typical locations as branchial cleft cyst (5) in mandibular angle, thyroglossal duct cyst (3) in visceral space embeded within the strap muscles, cystic hygroma (1) and cavernous hemangioma (1) in posterior cervical space with insinuating appearance. Two cases of ranula included one simple ranula localized in sublingual space and a plunging ranula extending to adjacent submandibular space. Seven cases of inflammatory lesions were characterized by multispatial locations and good contrast-enhancement of walls and adjacent tissue. Solid masses of low density mimicking cyst were two pleomorphic adenomas of submandibular gland and one neurilemmoma. It is considered that thorough analysis of the CT findings with attention to typical location, CT appearance, and the relationship with the adjacent structures usually leads to the correct diagnosis.

  11. The experimental study on bowel ischemia in closed loop obstruction by using multi-phase spiral CT

    International Nuclear Information System (INIS)

    Zhang Xiaoming; Yang Hanfeng; Huang Xiaohua; Tang Xianying; Jian Pu; Yang Zhengwei; Zhou Jiyong; Zhao Zongwen

    2005-01-01

    Objective: To evaluate the bowel ischemia in experimental closed loop obstruction by using multi-phase spiral CT. Methods: Twenty-four New Zealand rabbits of both sexes (mean age, 4 months, and mean body weight, 2.5-3.0 kg) were divided randomly into three groups with each group containing 8 rabbits. After clamping 10-15 cm segments of small bowel and their veins for 0.5 hours (Group A), 1-2 hours (Group B), and 3-5 hours (Group C), respectively, multi-phase spiral CT was performed at baseline, and at arterial, venous, and delayed phases after intravenous contrast administration. Then the rabbits were sacrificed to observe their surgical and histological changes. Two radiologists, blinded to the animal model classification and their histological results, individually reviewed the CT images to observe the CT appearances of the closed loop. Statistical significance criteria was determined by P 0.05) at baseline, however, they were significantly different (P<0.05) at all phases after enhancement. Among rabbits without necrotic closed loop, 11 of 13 had continuous enhancement at all phases, while only 1 of 11 rabbits with necrotic closed loop showed continuous enhancement (P<0.05). Conclusion: The ischemia of bowel wall in different phases after clamping small bowel and their veins can be evaluated by using enhanced multi-phase spiral CT. Continuous enhancement of bowel wall in multi-phase spiral CT can be seen prominently in the early bowel ischemia, but necrotic bowel shows no enhancement. (authors)

  12. CT findings of trigeminal neurinoma (root type)

    International Nuclear Information System (INIS)

    Munemoto, Shigeru; Ishiguro, Shuzo; Kimura, Akira; Shoin, Katsuo; Futami, Kazuya; Rikimaru, Shigeho; Shimizu, Hiroshi; Inoue, Kazuhiko

    1986-01-01

    The CT findings of three patients with trigeminal neurinomas arising from the trigeminal nerve roots were analysed. The tumors were seated behind the posterior wall of the petrous bone: The tumors showed a low density, an isodensity, or a mixed iso and low density on the CT scan. After contrast infusion, the two tumors were markedly enhanced, and the last showed rim enhancement. All the tumors had cystic lesions. None of the tumors had surrounding brain edema. In the 1st case, the tumor compressed the cerebellum mainly; in the 2nd case, it compressed the brain stem, and in the last case, it compressed both the brain stem and the cerebellum. The 2nd case is easy to differentiate from the acoustic neurinoma by its location. The other two cases could be differentiated from the acoustic neurinoma by means of CECT, because the enhanced masses were attached to the apex of the petrous bone. Metrizamide CT cisternography played an important role in circumscribing the tumor. (author)

  13. CT and the diagnosis of myopathies. Preliminary findings in 42 cases

    Energy Technology Data Exchange (ETDEWEB)

    Calgo, M; Crisi, G; Martinelli, C; Colombo, A; Schoenhuber, R; Gibertoni, M

    1986-01-01

    A total of 42 patients with myopathies underwent CT scans in order to study the relationship between CT images and clinical findings. CT is a valuable diagnostic aid to distinguish primary from neurogenic myopathies, to facilitate directed biopsy and finally to classify the disease according to the degree and extent of the muscular lesion. (orig.).

  14. CT and MR findings in HIV-negative neurosyphilis

    Energy Technology Data Exchange (ETDEWEB)

    Peng Fuhua [Department of Neurology, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, 510630 Guangdong Province (China)], E-mail: pfh93@21cn.com; Hu Xueqiang [Department of Neurology, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, 510630 Guangdong Province (China)], E-mail: huxueqiangqm@yahoo.com.cn; Zhong Xiufeng [State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center of Sun Yat-Sen University, 54 Xianlie Road, Guangzhou, 510060 Guangdong Province (China)], E-mail: xiufengzhong@yahoo.com.cn; Wei Qiu [Department of Neurology, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, 510630 Guangdong Province (China)], E-mail: qw9406@tom.com; Jiang Ying [Department of Neurology, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, 510630 Guangdong Province (China)], E-mail: jiangying722@163.com; Bao Jian [Department of Neurology, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, 510630 Guangdong Province (China)], E-mail: baoj92@tom.com; Wu Aimin [Department of Neurology, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, 510630 Guangdong Province (China)], E-mail: wuaim@126.com; Pei Zhong [Department of Neurology, First Affiliated Hospital of Sun Yat-Sen University, 89 Zhongshaner Road, Guangzhou, 510080 Guangdong Province (China)], E-mail: peizhong@yahoo.com

    2008-04-15

    Background and purpose: The purpose of this study was to describe and evaluate neuroimaging findings of patients with neurosyphilis. Methods: The neuroimaging studies of 14 patients with documented neurosyphilis were reviewed. Diagnosis was established in 14 patients with cerebrospinal fluid for a Treponema Pallidum Particle Agglutination (TPPA) test. All patients had reactive TPPA and Unheated Serum Regain test (USR) in their sera. Imaging studies included plain, contrast-enhanced CT of the brain, plain and gadolinium-enhanced MR, and MR angiography. Results: In the 14 HIV-negative patients with neurosyphilis, CT and MR showed the presence of cerebral infarction in six cases, arteritis in four cases, nonspecific white matter lesion in three cases, acute syphilitic meningitis in one case and normal neuroimaging finding in one case. In addition, 4 in 14 patients had general paresis, and MRI showed high signal intensity on T2 -weighted images involving frontotemporal lobes, hippocampus and periventricular area. Treatment with penicillin significantly diminished the size of these high signal intensity on T2-weighted images with general paresis. Conclusion: These results suggest that MR and CT images have some characteristic manifestations in patients of neurosyphilis. Because early diagnosis and treatment of neurosyphilis are crucial to avoid persistent brain damage, the neuroimaging findings are valuable adjunct to clinical diagnosis and to provide useful information to follow-up after therapy.

  15. Coronary artery anomalies in adults: imaging at dual source CT coronary angiography

    International Nuclear Information System (INIS)

    Laspas, Fotios; Roussakis, Arkadios; Mourmouris, Christos; Kritikos, Nikolaos; Efthimiadou, Roxani; Andreou, John

    2013-01-01

    Congenital abnormalities of the coronary arteries have an incidence of 1%, and most of these are benign. However, a small number are associated with myocardial ischaemia and sudden death. Various imaging modalities are available for coronary artery assessment. Recently, multi-detector CT has emerged as an accurate diagnostic tool for defining coronary artery anomalies. The purpose of this pictorial essay is to review the dual source CT appearance of congenital anomalies of the coronary arteries in adults.

  16. Multiple detector-row CT angiography of the renal and mesenteric vessels

    Energy Technology Data Exchange (ETDEWEB)

    Fleischmann, Dominik. E-mail: dominik.fleischmann@univie.ac.at

    2003-03-01

    Computed tomography angiography (CTA) of the abdomen with multiple detector-row computed tomography (MD-CT) is an effective technique for minimally invasive imaging of the renal arteries and the visceral vasculature. This article reviews the clinical and technical aspects of MD-CT angiography in terms of image acquisition and reconstruction parameters, contrast medium application, and three-dimensional visualization with special attention to renal and mesenteric vascular imaging. Because of its high sensitivity to detect renal artery stenosis on the one hand, and because a normal renal CTA virtually excludes the presence of a significant renal artery stenosis on the other hand, renal CTA plays a useful role in the management of patients with suspected renovascular hypertension. Mesenteric CTA is a useful tool for visualizing normal vascular anatomy and its variants--particularly in the setting of organ transplantation. Vascular pathology, e.g. atherosclerotic disease (abdominal angina), or aneurysms of the visceral arteries are reliably assessed with CTA. Mesenteric CTA is an invaluable adjunct to abdominal CT in the setting of abdominal emergencies, because of its ability to detect the causes of acute intestinal ischemia (superior mesenteric artery embolism or thrombosis, superior mesenteric vein thrombosis). Accurate timing of the CTA acquisition and the subsequent parenchymal phase acquisition relative to the contrast medium transit time is critical to obtain excellent image quality in double-pass abdominal CT acquisitions.

  17. Lung cancer in patients with idiopathic pulmonary fibrosis: frequency and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hak Jong; Im, Jung Gi; Ahn, Joong Mo; Yeon, Kyung Mo [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    1994-12-15

    The incidence of lung cancer in patients with idiopathic pulmonary fibrosis(lPF) is higher than that of general population. To evaluate the frequency and CT findings of lung cancer associated with idiopathic pulmonary fibrosis, we analyzed 19 patients with lung cancer associated with idiopathic pulmonary fibrosis. We analyzed retrospectively 19 patients with histologically confirmed lung cancer out of 208 patients diagnosed as IPF either by CT and clinical findings(n=188) or histologically(n=20). All 19 patients were male, aged 40-85 years (mean 66 years). Scanning techniques were conventional CT in 12 patients, HRCT in 1 patient and both conventional CT and HRCT in 6 patients. We analyzed the CT patterns of lung cancer and IPF, locations of the tumor and histologic types of lung cancer. The incidence of lung cancer in patients with idiopathic pulmonary fibrosis was 9.1%(19/208). In 11 of 19 patients, CT findings of lung cancer were ill-defined consolidation-like mass. Lung cancer was located mainly in lower lobes(right lower lobe; 10/19, left lower lobe; 5/19) and at the periphery(12/19). Histologically, squamous cell carcinoma was the most common cell type (11/19). The incidence of lung cancer in patients with idiopathic pulmonary fibrosis was much higher than that of general population. Typical CT findings of lung cancer were predominantly ill-defined consolidation like mass at the peripheral lung portion which is the location where the most advanced fibrosis occur.

  18. Lung cancer in patients with idiopathic pulmonary fibrosis: frequency and CT findings

    International Nuclear Information System (INIS)

    Lee, Hak Jong; Im, Jung Gi; Ahn, Joong Mo; Yeon, Kyung Mo

    1994-01-01

    The incidence of lung cancer in patients with idiopathic pulmonary fibrosis(lPF) is higher than that of general population. To evaluate the frequency and CT findings of lung cancer associated with idiopathic pulmonary fibrosis, we analyzed 19 patients with lung cancer associated with idiopathic pulmonary fibrosis. We analyzed retrospectively 19 patients with histologically confirmed lung cancer out of 208 patients diagnosed as IPF either by CT and clinical findings(n=188) or histologically(n=20). All 19 patients were male, aged 40-85 years (mean 66 years). Scanning techniques were conventional CT in 12 patients, HRCT in 1 patient and both conventional CT and HRCT in 6 patients. We analyzed the CT patterns of lung cancer and IPF, locations of the tumor and histologic types of lung cancer. The incidence of lung cancer in patients with idiopathic pulmonary fibrosis was 9.1%(19/208). In 11 of 19 patients, CT findings of lung cancer were ill-defined consolidation-like mass. Lung cancer was located mainly in lower lobes(right lower lobe; 10/19, left lower lobe; 5/19) and at the periphery(12/19). Histologically, squamous cell carcinoma was the most common cell type (11/19). The incidence of lung cancer in patients with idiopathic pulmonary fibrosis was much higher than that of general population. Typical CT findings of lung cancer were predominantly ill-defined consolidation like mass at the peripheral lung portion which is the location where the most advanced fibrosis occur

  19. CT and MR findings of primitive neuroectodermal tumor

    International Nuclear Information System (INIS)

    Kook, Shin Ho; Kim, In One; Chang, Kee Hyun; Han, Moon Hee; Cho, Byung Kyu

    1991-01-01

    Cerebral primitive neuroectodermal tumor (PNET), consisting of undifferentiated primitive cells, is a neoplasm of children and young adults that occurs predominantly in the supratentorial compartment. In this report, we retrospectively reviewed and analyzed 18 CT and 6 MR findings in 18 patients with pathologically-proven PNET to discover the characteristic findings, if may. The most characteristic feature of the PNETs was a well-defined multilobular oval or round large mass with components of peripheral cystic change or calcification in the cerebral hemisphere, especially in the parietal lobe. Usually there was only minimal surrounding edema. The CT density of the tumor was iso - or slightly high density with homogeneous contrast enhancement in the solid portion and low density in the cystic area. MR findings demonstrated iso - signal intensity on both T1 - weighted (T1WI) and T2-weighted (T2WI) images and dense enhancement in the solid element. The cystic portion revealed low intensity on T1WI and high intensity on T2WI

  20. Brain tumor and CT, 1. Relationship between the consistency of a brain tumor and the CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, N.; Katada, K.; Shinomiya, Y.; Sano, H.; Kanno, T. (Fujita Gakuen Univ., School of Medicine, Toyoake, Aichi (Japan))

    1981-08-01

    It is very important for a neurosurgeon to know the consistency of a brain tumor preoperatively, since the information is of much use in indicating the likely difficulty of the operation, which operative tools should be selected, the amount of bleeding to be expected from the tumor, and so on. The authors, therefore, tried to evaluate the consistency of brain tumors preoperatively. Twenty-seven cases in which the margin of the tumor was made clear with a homogeneous stain were studied concerning the relationship between the tumor consistency and the CT findings. The results are as follows: 1) A higher CT number on a plain CT indicated a harder consistency of the tumor. 2) A lesser contrast index (CT number on enhancement CT/CT number on plain CT) showed a harder consistency of the tumor.