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)

Internal carotid arterial occlusion in computed tomography. Correlation of CT and angiographic findings

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Harada, K.; Miura, T.; Nishikubo, Y.; Kawai, R.; Mitomo, M. (Osaka Univ. (Japan). Faculty of Medicine)

1981-09-01

The computed tomographic appearance of internal carotid arterial occlusion was reviewed in 33 patients. In 23 of them, who underwent 4-vessel study, the angiographic and CT findings were compared. Ten patients were disclosed to have watershed infarction by CT. Seven of them had watershed processes in the centrum semiovale which were considered to be terminal infarction. Patients who showed watershed infarction under CT revealed inadequate circle of Willis and well-developed cortical anastomosis under angiography. Unilaterally accentuated cerebral atrophy, which we have called asymmetrical atrophy in this paper, was noted in 10 patients. The findings of asymmetrical cerebral atrophy sometimes resemble the changes secondary to old infarction. However, the changes in the lateral ventricle caused by asymmetrical cerebral atrophy are somewhat different from those resulting from old infarction. The angiographic findings suggested that asymmetrical cerebral atrophy is, in addition to being associated with incomplete circle of Willis, also associated with local circulatory disturbances which further decrease the regional cerebral blood flow in the affected hemisphere.

Multidetector-row CT duodenography in familial adenomatous polyposis: a pilot study

International Nuclear Information System (INIS)

Taylor, S.A.; Halligan, S.; Moore, L.; Saunders, B.P.; Gallagher, M.; Phillips, R.K.S.; Bartram, C.I.

2004-01-01

AIM: To investigate the feasibility of using multidetector-row computed tomography (CT) duodenography to stage duodenal polyposis in patients with familial adenomatous polyposis. MATERIALS AND METHODS: Six patients underwent multidetector-row CT duodenography before upper gastrointestinal endoscopy. A single-blinded radiologist used a surface shaded three-dimensional endoluminal fly though and two-dimensional axial and multiplanar reformats to assign a score for maximum polyp size and number based on the Spigelman classification. Comparison was made with the corresponding Spigelman scores obtained from subsequent endoscopy. RESULTS: CT duodenography was technically successful in five of six patients. The CT derived Spigelman score based on maximum polyp size was accurate in all five patients. The CT derived Spigelman score based on polyp number was accurate in only two cases: Polyp number was overestimated in one patient and underestimated in a further two. In retrospect, fine carpeting of tiny duodenal polyps was poorly visualized with CT. CONCLUSIONS: CT duodenography is technically feasible and accurately predicts maximum polyp size but CT estimates of polyp number are relatively inaccurate. CT duodenography potentially has a useful role for duodenal surveillance in those patients intolerant of conventional endoscopy

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)

Multidetector-row CT: economics and workflow

International Nuclear Information System (INIS)

Pottala, K.M.; Kalra, M.K.; Saini, S.; Ouellette, K.; Sahani, D.; Thrall, J.H.

2005-01-01

With rapid evolution of multidetector-row CT (MDCT) technology and applications, several factors such ad technology upgrade and turf battles for sharing cost and profitability affect MDCT workflow and economics. MDCT workflow optimization can enhance productivity and reduce unit costs as well as increase profitability, in spite of decrease in reimbursement rates. Strategies for workflow management include standardization, automation, and constant assessment of various steps involved in MDCT operations. In this review article, we describe issues related to MDCT economics and workflow. (orig.)

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.

Use of multidetector row CT with volume renderings in right lobe living liver transplantation

International Nuclear Information System (INIS)

Ishifuro, Minoru; Akiyama, Yuji; Kushima, Toshio; Horiguchi, Jun; Nakashige, Aya; Tamura, Akihisa; Marukawa, Kazushi; Fukuda, Hiroshi; Ono, Chiaki; Ito, Katsuhide

2002-01-01

Multidetector row CT is a feasible diagnostic tool in pre- and postoperative liver partial transplantation. We can assess vascular anatomy and liver parenchyma as well as volumetry, which provide useful information for both donor selection and surgical planning. Disorders of the vascular and biliary systems are carefully observed in recipients. In addition, we evaluate liver regeneration of both the donor and the recipient by serial volumetry. We present how multidetector row CT with state-of-the-art three-dimensional volume renderings may be used in right lobe liver transplantation. (orig.)

Breast multidetector-row CT with histopathologic correlation

International Nuclear Information System (INIS)

Takeuchi, Makiko; Yamashita, Akiyoshi; Ohgi, Kazuyuki; Kobori, Kenichi; Furukawa, Takashi

2004-01-01

The purpose of this study was to evaluate the correlation between multidetector-row CT (MDCT) and histopathologic findings using the same MDCT image as the histopathologic cross-section. MDCT with contrast enhancement was performed in 10 patients with breast cancers (8 invasive ductal carcinomas, one invasive lobular carcinoma, and one non-invasive ductal carcinoma). We tried to reconstruct multiplanar reconstructions (MPR) in the same plane as the histopathologic cross-section, and we evaluated the histopathologic findings of the false-positive lesions. In all cases, we obtained the same MDCT image as the histopathologic cross-section. There were 10 main lesions and 18 other lesions. In the other lesions, we found no false-negative lesions and 11 false-positive lesions. False-positive lesions included periductal fibrosis, cystic change, duct papillomatosis, sclerosing adenosis, fibroadenoma, and others. Using MDCT of the breast, it is possible to obtain good correlation between CT images and histopathologic findings. MDCT is thought to be useful in the evaluation CT findings on the basis of histopathologic evidence. (author)

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)

T-staging of gastric cancer of air-filling multidetector-row CT: Comparison with hydro-multidetector-row CT

Energy Technology Data Exchange (ETDEWEB)

Kumano, Seishi, E-mail: kumano@radiol.med.kindai.ac.jp [Department of Radiology, Kinki University School of Medicine, Osakasayama, Osaka 589-8511 (Japan); Okada, Masahiro; Shimono, Taro; Kuwabara, Masatomo; Yagyu, Yukinobu; Imaoka, Izumi; Ashikaga, Ryuichiro; Ishii, Kazunari; Murakami, Takamichi [Department of Radiology, Kinki University School of Medicine, Osakasayama, Osaka 589-8511 (Japan)

2012-11-15

Purpose: The purpose of this study was to evaluate the accuracy of T-staging of gastric cancer by air-filling multidetector-row CT (air-MDCT) compared with water-filling MDCT (hydro-MDCT). Materials and methods: One hundred fifteen patients with histologically diagnosed gastric cancer were included in this study. Fifty-eight patients underwent air-MDCT, and the remaining 57 had hydro-MDCT using a 64-channel scanner. Based on the volumetric data of contrast-enhanced MDCT obtained about 75 s after intravenously injecting 525 mg iodine per kilogram patients weight (525 mgI/kg) nonionic contrast material at the rate of 2 ml/s, oblique coronal and oblique sagittal multi-planar reformatted images perpendicular to the stomach wall, including the tumor, were reconstructed on a workstation. Mural invasion of gastric cancer into the gastric wall, as visualized by CT, was classified according to the TNM classification, and the results of T-staging by MDCT were compared with those by pathologic analysis after surgery. Results: Correct assessment of T-staging by air-CT was achieved in 48 of 58 patients (83%), and that by hydro-MDCT was 49 of 57 patients (86%). The sensitivity, specificity, and accuracy of the technique in determining the invasion of serosa were 88%, 93%, and 91% for air-CT and 83%, 95%, and 91% for hydro-CT. There were no significant differences between hydro-MDCT and air-MDCT in sensitivity (P = 0.73), specificity (P = 0.71) and accuracy (P = 0.98). Conclusion: Air-MDCT is a very valuable tool in T-staging of gastric cancer as well as hydro-MDCT.

Multidetector row CT for imaging the paediatric tracheobronchial tree

International Nuclear Information System (INIS)

Papaioannou, Georgia; Young, Carolyn; Owens, Catherine M.

2007-01-01

The introduction of multidetector row computed tomography (MDCT) scanners has altered the approach to imaging the paediatric thorax. In an environment where the rapid acquisition of CT data allows general hospitals to image children instead of referring them to specialist paediatric centres, it is vital that general radiologists have access to protocols appropriate for paediatric applications. Thus a dramatic reduction in the delivered radiation dose is ensured with optimal contrast bolus delivery and timing, and inappropriate repetition of the scans is avoided. This article focuses on the main principles of volumetric CT imaging that apply generically to all MDCT scanners. We describe the reconstruction techniques for imaging the paediatric thorax and the low-dose protocols used in our institution on a 16-slice detector CT scanner. Examples of the commonest clinical applications are also given. (orig.)

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.)

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, ...

Analysis of 64-row multidetector CT images for preoperative angiographic evaluation of potential living kidney donors; Analyse der mehrphasigen 64-Zeilen-Multidetektor-Computertomographie zur praeoperativen angiographischen Evaluation potenzieller Lebendnierenspender

Energy Technology Data Exchange (ETDEWEB)

Blondin, D.; Andersen, K.; Kroepil, P.; Cohnen, M.; Moedder, U.; Jung, G. [Universitaetsklinikum Duesseldorf, Institut fuer Diagnostische Radiologie, Duesseldorf (Germany); Sandmann, W. [Universitaetsklinikum Duesseldorf, Klinik fuer Gefaesschirurgie und Nierentransplantation, Duesseldorf (Germany); Ivens, K. [Universitaetsklinikum Duesseldorf, Klinik fuer Nephrologie, Duesseldorf (Germany)

2008-07-15

Anatomical imaging and the ascertainment of any anomalies in the renal vessels and the ureters are essential in the planning of a kidney donation. The aim of the present study was to assess the value of 64-row multidetector CT in noninvasive examination of the renal vessels and ureters of potential living kidney donors. The evaluation embraced 63 living renal donors (LNS) who underwent preoperative CT examination from December 2004 to January 2007. The examinations were all carried out using a Somatom Sensation -Cardiac 64 (Siemens Medical Solutions, Germany). As well as CT angiography (CTA), a venous phase of the abdomen and a late phase after 15 min using low-dose technique were performed for CT urography (CTU). The radiological findings were compared with the surgical results, or with the angiograms in 2 cases. Sensitivity, specificity and both negative and positive predictive value were calculated. In the 63 (31 female, 32 male) donors CTA had a sensitivity of 100% in examination of the main and accessory renal arteries and of 98.3% when the venous and ureteric anatomy were assessed. The sensitivity of low-dose CTU was also 100%. The findings recorded in this study indicate that noninvasive preoperative planning with 64-row multidetector CTA and CTU is a reliable 'one-stop shopping' method of examination for potential living kidney donors. (orig.) [German] Die anatomische Darstellung und Erfassung moeglicher Anomalien der Nierengefaesse und Ureteren ist fuer die Planung einer Lebendnierenspende von essenzieller Bedeutung. Die vorliegende Untersuchung soll die Wertigkeit der nichtinvasiven Evaluation mit der 64-Zeilen-Multidetektor-CT untersuchen. In die Auswertung wurden 63 Lebendnierenspender (LNS) eingeschlossen, die im Zeitraum 12.2004 bis 01.2007 mit der CT praeoperativ untersucht wurden. Die Untersuchungen erfolgten mit einem Somatom-Sensation-Cardiac-64 (Siemens Medical Solutions, Deutschland). Neben einer CT-Angiographie (CTA) wurden eine

The quality of reconstructed 3D images in multidetector-row helical CT: experimental study involving scan parameters

International Nuclear Information System (INIS)

Shin, Ji Hoon; Lee, Ho Kyu; Choi, Choong Gon; Suh, Dae Chul; Lim, Tae Hwan; Kang, Weechang

2002-01-01

To determine which multidetector-row helical CT scanning technique provides the best-quality reconstructed 3D images, and to assess differences in image quality according to the levels of the scanning parameters used. Four objects with different surfaces and contours were scanned using multidetector-row helical CT at three detector-row collimations (1.25, 2.50, 5.00 mm), two pitches (3.0, 6.0), and three different degrees of overlap between the reconstructed slices (0%, 25%, 50%). Reconstructed 3D images of the resulting 72 sets of data were produced using volumetric rendering. The 72 images were graded on a scale from 1 (worst) to 5 (best) for each of four rating criteria, giving a mean score for each criterion and an overall mean score. Statistical analysis was used to assess differences in image quality according to scanning parameter levels. The mean score for each rating criterion, and the overall mean score, varied significantly according to the scanning parameter levels used. With regard to detector-row collimation and pitch, all levels of scanning parameters gave rise to significant differences, while in the degree of overlap of reconstructed slices, there were significant differences between overlap of 0% and of 50% in all levels of scanning parameters, and between overlap of 25% and of 50% in overall accuracy and overall mean score. Among the 18 scanning sequences, the highest score (4.94) was achieved with 1.25 mm detector-row collimation, 3.0 pitch, and 50% overlap between reconstructed slices. Comparison of the quality of reconstructed 3D images obtained using multidetector-row helical CT and various scanning techniques indicated that the 1.25 mm, 3.0, 50% scanning sequence was best. Quality improved as detector-row collimation decreased; as pitch was reduced from 6.0 to 3.0; and as overlap between reconstructed slices increased

Hereditary haemorrhagic telangiectasia: study of hepatic vascular alterations with multi-detector row helical CT and reconstruction programs

International Nuclear Information System (INIS)

Memeo, Maurizio; Stabile Ianora, Amato Antonio; Scaldapane, Arnaldo; Rotondo, Antonio; Angelelli, Giuseppe; Suppressa, Patrizia; Cirulli, Anna; Sabba', Carlo

2005-01-01

Purpose: To evaluate hepatic alterations in patients affected by Hereditary Haemorrhagic Telangiectasia (HHT) by using multidetector row helical CT (MDCT) and new reconstruction programs. Materials and methods: An MDCT multiphasic study of the liver was performed in 105 consecutive patients: 89 considered to be affected by HHT and 16 with suspicion of disease alone. The scan delay was determined by using a test bolus of contrast material. The CT examination was performed with a triphasic technique (double arterial phase and portal venous phase). multiplanar and angiographic reconstructions were then obtained, and the images checked for the presence of shunts, hepatic perfusion disorders, vascular lesions (telangiectasis and large confluent vascular masses), indirect signs of portal hypertension, and anatomical vascular variants. Results: Hepatic vascular alterations were found in 78/105 cases (67/89) patients affected by HHT and 11/16 patients with clinical suspicion alone). Therefore HHT diagnosis was excluded in 5 patients. 78/100 (78%) patients with HHT had intrahepatic vascular alterations: arterioportal shunts in 40/78 (51.2%) arteriosystemic shunts in 16/78 (20.5%) and both shunt types in 22/78 (28.3%). Intraparenchymal perfusion disorders were found in 46/78 (58.9%) patients. Telangiectasis were recognised in 50/78 (64.1%) patients. Large confluent vascular masses (LCVMs) were identified in 20/78 (25.6%) patients. indirect signs of portal hypertension were found in 46/78 (58.9%) cases. Variant hepatic arterial anatomy was present in 38/100 cases (38%). Conclusions: Multiphasic MDCT and the new reconstruction programs enable the identification and characterisation of the complex vascular alterations typical of HHT [it

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

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.

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.

Traumatic thoracic injury: the role of Multidetector-row CT

Energy Technology Data Exchange (ETDEWEB)

Park, Kyung Joo; Kang, Doo Kyung; Kim, Tae Hee [Ajou University School of Medicine, Suwon (Korea, Republic of)

2006-05-15

The introduction of Multidetector-row CT (MDCT) has revolutionized the diagnostic strategy of multitrauma patients. The rapid acquisition of a large scanning volume with a thin slice collimation allows for motion-free images of high spatial resolution, and this enables the application of the multiplanar reformat (MPR) and 3D volume-rendering (VR) images. The MPR images more accurately demonstrate aortic rupture or dissection, diaphragmatic injuries and fracture of vertebrae, sternum and costal cartilages. Diagnosing vascular injuries can be aided by using the MIP images. Rib fracture, trachea and bronchial laceration are more easily detected by the 3D images, while airway and vascular injuries can be detected from performing virtual endoscopy. We introduce our current CT imaging protocol and we present our clinical experience with using MDCT in the assessment of patients with blunt thoracic trauma.

Multidetector-row CT angiography of hepatic artery: comparison with conventional angiography

International Nuclear Information System (INIS)

Kim, Jin Woong; Jeong, Yong Yeon; Yoon, Woong; Kim, Jae Kyu; Park, Jin Gyoon; Seo, Jeong Jin; Kang, Heoung Keun

2003-01-01

To determine the usefulness of three-dimensional CT angiography using multidetector-row CT (MD-CT) for delineating the arterial anatomy of the liver. Hepatic arterial three-dimensional CT angiography was performed using MDCT (lightspeed Qx/I; GE medical systems, milwaukee, Wis., U.S.A.) in 45 patients with HCC undergoing conventional angiography for transcatheter hepatic arterial chemoembolization. The scanning parameters during the early arterial phase were 2.5 mm slice thickness, 7.5 mm rotation of table speed, and a pitch of 3. Images were obtained by one radiologist using maximum intensity projection from axial CT images obtained during the early arterial phase. Two radiologists blinded to the findings of conventional angiography independently evaluated the hepatic arterial anatomy and the quality of the images obtained. Compared with conventional angiography, reader A correctly evaluated the hepatic arterial anatomy depicted at three-dimensional CT angiography. Reader B's evaluation was correct in 40 of 45 patients. Interobserver agreement was good (kappa value, 0.73), and both readers assessed the quality of three-dimensional CT angiography as excellent. Three-dimensional CT angiography using MDCT was accurate for delineating the arterial anatomy of the liver, and interobserver agreement was good. The modality may provide, prior to conventional angiography, valuable information regrading a patient's hepatic arterial anatomy

The value of contrast-enhanced 64-row CT in differentiating benign from malignant serous ovarian neoplasms

International Nuclear Information System (INIS)

Dong Tianfa; Wu Meixian; Zhang Jiayun; Song Ting

2009-01-01

Objective: To assess the diagnostic value of contrast-enhanced 64-row CT scanning in deciding benign or malignant serous ovarian tumors. Methods: Fifty-eight cases of serous ovarian tumors proved pathologically were reviewed, including 25 malignant tumors, 25 benign, 8 borderline tumors. All patients underwent 64-row CT scanning, including plain scanning and contrast-enhance scanning. The tumors' shape, density, blood supply and enhancement features were evaluated. Results: Twenty-five cases of benign serous cystic adenoma were mostly unicameral, and showed a moderate mural enhancement only in 4 cases (16%) due to chronic pelvic infection and the others (21/25, 84%) had no of slight enhancement. Malignant tumors were cystic-solid mass with unclear margin, irregular shape and septa. Twenty-two cases of serous cystadenocarcinoma out of 25 cases (88%) appeared obvious enhancement and other 3 cases no enhancement. And 7 cases out of 8 (87.5%) borderlined serous cystadenomas showed different enhancement patterns. Conclusion: Benign ovarian serous neoplasms were mostly unicameral and no strong mural enhancement, suggesting a lack of blood supply. While, there were obvious enhancement in the ovarian serous cystadenocarcinoma and borderline serous cystadenoma with malignant potential. The 64-row CT is helpful for differentiating the nature of the serous ovarian neoplasm. (authors)

Invaded depth of extrahepatic bile duct cancer diagnosed on angiographic CT during late contrast enhancement

International Nuclear Information System (INIS)

Kikuyama, Masataka; Sasada, Yuzo; Koide, Shigeki; Hirai, Ritsuko; Oota, Yuji

2006-01-01

Thirteen patients with extrahepatic bile duct cancer were evaluated for enhancement pattern and tumor feature during late contrast enhancement on angiographic CT (AG-CT), performed before surgery. Eleven patients with late contrast enhancement had advanced cancers with invasion over the subserosal layer. Eight of these patients whose cancer had an irregular outer layer had invasion over the serosal layer (≥panc 1 b, General Rules for Surgical and Pathological Studies on Cancer of the Biliary Tract, Japanese Society of Biliary Surgery). Seven of the 13 patients had intra-pancreatic bile duct cancer. Among them, five had an irregular outer layer of the intra-pancreatic bile duct cancer; one of three with a wall thickness under 5 mm on AG-CT had panc 1 b invasion, and the other two had panc 2 (General Rules for Surgical and Pathological Studies on Cancer of the Biliary Tract, Japanese Society of Biliary Surgery) invasion. Two with a wall thickness over 5 mm on AG-CT had panc 2 invasion. These results suggest that late contrast enhancement on AG-CT is effective for diagnosing the depth of tumor invasion of the bile duct. (author)

Multidetector-row helical CT: analysis of time management and workflow

Energy Technology Data Exchange (ETDEWEB)

Roos, Justus E.; Desbiolles, Lotus M.; Willmann, Juergen K.; Weishaupt, Dominik; Marincek, Borut; Hilfiker, Paul R. [Institute of Diagnostic Radiology, University Hospital Zurich (Switzerland)

2002-03-01

The purpose of this study was to evaluate time management and workflow for multidetector-row helical CT (MDCT). Time for patient and data handling of at total of 580 patients were evaluated at two different time periods (December 1999, August 2000), each for the following baseline measurements: (a) change of clothes/instruction; (b) patient placement on the CT table/i.v. catheter; (c) CT planning and programming; (d) CT data acquisition; (e) CT data reconstruction; (f) CT data storage/printing. All imaging was performed on a Somatom Volume Zoom (Siemens, Erlangen, Germany). Time measurements summarized for different CT protocols revealed the following: (a) 5:01 min ({+-}2.06 min); (b) 4:36 min ({+-}2.43 min); (c) 4:11 min ({+-}2.55 min); (d) 0:43 min ({+-}0.15 min); (e) 6:59 min ({+-}2.39 min); (f) 09:51 min ({+-}3.51 min). Planning and programming was most time-consuming for CT angiography, whereas chest and abdominal CT needed only 3:26 and 3:30 min, respectively. Reconstruction time was highest for HRCT (9:22 min) and CTA (9:03 min). Data storage/printing was most time-consuming for HRCT (13:02 min), followed by combined neck-chest-abdomen examinations (12:19 min). Comparing the two time periods, during which a software update was performed, a mean time reduction of 4:31 min per patient (15%, p<0.001) was achieved. Whereas CT data acquisition time is no longer a problem with MDCT, patient management, data reconstruction, and data storage are the most time-consuming parts. Well-trained technicians, state-of-the-art workstations, and fast networking are the most important factors to improve workflow. (orig.)

The anterior choroidal artery syndrome. Pt. 2. CT and/or MR in angiographically verified cases

International Nuclear Information System (INIS)

Takahashi, S.; Ishii, K.; Matsumoto, K.; Higano, S.; Ishibashi, T.; Suzuki, M.; Sakamoto, K.

1994-01-01

We reviewed 12 cases of infarcts in the territory of the anterior choroidal artery (AChA) on CT and/or MRI. In each case vascular occlusion in the region was verified angiographically. Although the extent of the lesion on CT/MR images was variable, all were located on the axial images within an arcuate zone between the striatium anterolaterally and the thalamus posteromedially. The distribution of the lesions on mutiplanar MRI conformed well to the territory of the AChA demonstrated microangiographically. The variability of the extent of the infarcts may be explained by variations in the degree of occlusive changes in the AChA or the development of collateral circulation through anastomoses between the AChA and the posterior communicating and posterior cerebral arteries. The extent of the lesion appeared to be closely related to the degree of neurological deficit. (orig.)

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.

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

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)

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)

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

Thin-section multiplanar reformats from multidetector-row CT data: Utility for assessment of regional tumor extent in non-small cell lung cancer

International Nuclear Information System (INIS)

Higashino, Takanori; Ohno, Yoshiharu; Takenaka, Daisuke; Watanabe, Hirokazu; Nogami, Munenobu; Ohbayashi, Chiho; Yoshimura, Masahiro; Satouchi, Miyako; Nishimura, Yoshihiro; Fujii, Masahiko; Sugimura, Kazuro

2005-01-01

Purpose: To determine the clinical utility of thin-section multiplanar reformats (MPRs) from multidetector-row CT (MDCT) data sets for assessing the extent of regional tumors in non-small cell lung cancer (NSCLC) patients. Materials and methods: Sixty consecutive NSCLC patients, who were considered candidates for surgical treatment, underwent contrast-enhanced MDCT examinations, surgical resection and pathological examinations. All MDCT examinations were performed with a 4-detector row computed tomography (CT). From each raw CT data set, 5 mm section thickness CT images (routine CT), 1.25 mm section thickness CT images (thin-section CT) and 1.25 mm section thickness sagittal (thin-section sagittal MPR) and coronal images (thin-section coronal MPR) were reconstructed. A 4-point visual score was used to assess mediastinal, interlobar and chest wall invasions on each image set. For assessment of utility in routine clinical practice, mean reading times for each image set were compared by means of Fisher's protected least significant difference (PLSD) test. A receiver operator characteristic (ROC) analysis was performed to determine the diagnostic capability of each of the image data sets. Finally, sensitivity, specificity and accuracy of the reconstructed images were compared by McNemar test. Results: Mean reading times for thin-section sagittal and coronal MPRs were significantly shorter than those for routine CT and thin-section CT (p < 0.05). Areas under the curve (Azs) showing interlobar invasion on thin-section sagittal and coronal MPRs were significantly larger than that on routine CT (p = 0.03), and the Az on thin-section sagittal MPR was also significantly larger than that on routine CT (p = 0.02). Accuracy of chest wall invasion by thin-section sagittal MPR was significantly higher than that by routine CT (p = 0.04). Conclusion: Thin-section multiplanar reformats from multidetector-row CT data sets are useful for assessing the extent of regional tumors in non

Whole-brain 320-detector row dynamic volume CT perfusion detected crossed cerebellar diaschisis after spontaneous intracerebral hemorrhage

Energy Technology Data Exchange (ETDEWEB)

Fu, Jun; Chen, Wei-jian; Wang, Mei-hao; Li, Jian-ce; Zhang, Qian; Xia, Neng-zhi; Yang, Yun-jun [Wenzhou Medical University, Department of Radiology, First Affiliated Hospital, Wenzhou (China); Wu, Gui-yun [Cleveland Clinics Foundation, Department of Nuclear Medicine, Imaging Institute, Cleveland, OH (United States); Cheng, Jing-liang; Zhang, Yong [Zhengzhou University, Department of Radiology, First Affiliated Hospital, Zhengzhou (China); Zhuge, Qichuan [Wenzhou Medical University, Department of Neurosurgery, First Affiliated Hospital, Wenzhou (China)

2014-11-09

The purpose of this study was to evaluate the value of 320-detector row CT used to detect crossed cerebellar diaschisis (CCD) in patients with unilateral supratentorial spontaneous intracerebral hemorrhage (SICH). We investigated 62 of 156 patients with unilateral supratentorial SICH using 320-detector row CT scanning. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), mean transit time (rMTT), and time to peak (rTTP) levels were measured in different regions of interest (ROIs) that were manually outlined on computed tomography perfusion (CTP) for the cerebrum, including normal-appearing brain tissue that surrounded the perilesional low-density area (NA) and the perihematomal low-density area (PA) in all patients and the cerebellum (ipsilateral and contralateral) in CCD-positive patients. Of 62 cases, a total of 14 met the criteria for CCD due to cerebellar perfusion asymmetry on CTP maps. In the quantitative analysis, significant differences were found in the perfusion parameters between the contralateral and ipsilateral cerebellum in CCD-positive cases. No significant differences were found between the CCD-positive group and the CCD-negative group according to the hematoma volume, NIHSS scores, and cerebral perfusion abnormality (each P > 0.05). The correlation analysis of the degree of NA, PA perfusion abnormality, and the degree of CCD severity showed negative and significant linear correlations (R, -0.66∝-0.56; P < 0.05). 320-detector row CT is a robust and practicable method for the comprehensive primary imaging work-up of CCD in unilateral supratentorial SICH patients. (orig.)

Whole-brain 320-detector row dynamic volume CT perfusion detected crossed cerebellar diaschisis after spontaneous intracerebral hemorrhage

International Nuclear Information System (INIS)

Fu, Jun; Chen, Wei-jian; Wang, Mei-hao; Li, Jian-ce; Zhang, Qian; Xia, Neng-zhi; Yang, Yun-jun; Wu, Gui-yun; Cheng, Jing-liang; Zhang, Yong; Zhuge, Qichuan

2015-01-01

The purpose of this study was to evaluate the value of 320-detector row CT used to detect crossed cerebellar diaschisis (CCD) in patients with unilateral supratentorial spontaneous intracerebral hemorrhage (SICH). We investigated 62 of 156 patients with unilateral supratentorial SICH using 320-detector row CT scanning. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), mean transit time (rMTT), and time to peak (rTTP) levels were measured in different regions of interest (ROIs) that were manually outlined on computed tomography perfusion (CTP) for the cerebrum, including normal-appearing brain tissue that surrounded the perilesional low-density area (NA) and the perihematomal low-density area (PA) in all patients and the cerebellum (ipsilateral and contralateral) in CCD-positive patients. Of 62 cases, a total of 14 met the criteria for CCD due to cerebellar perfusion asymmetry on CTP maps. In the quantitative analysis, significant differences were found in the perfusion parameters between the contralateral and ipsilateral cerebellum in CCD-positive cases. No significant differences were found between the CCD-positive group and the CCD-negative group according to the hematoma volume, NIHSS scores, and cerebral perfusion abnormality (each P > 0.05). The correlation analysis of the degree of NA, PA perfusion abnormality, and the degree of CCD severity showed negative and significant linear correlations (R, -0.66∝-0.56; P < 0.05). 320-detector row CT is a robust and practicable method for the comprehensive primary imaging work-up of CCD in unilateral supratentorial SICH patients. (orig.)

Multidetector-Row CT Findings of an Internal Supravesical Hernia: A Case Report

International Nuclear Information System (INIS)

Kim, Sang Won; Shin, Hyeong Cheol; Kim, Hyung Hwan; Kim, Young Tong; Kim, Il Young; Kang, Kil Ho

2010-01-01

A supravesical hernia occurs in the supravesical fossa and is either classified as an external or internal supravesical hernia. Most patients with internal supravesical hernias present with small bowel obstruction. Internal supravesical hernias are less common than external supravesical hernia. To date, there are few reports describing the radiological findings of supravesical hernias. To our knowledge, this is the first reported multidetector row CT (MDCT) depiction of this type of hernia. We report here on the MDCT findings of a patient with an internal supravesical hernia presenting with small bowel obstruction

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.

Diagnostic value of multidetector row CT in rectal cancer staging: comparison of multiplanar and axial images with histopathology

International Nuclear Information System (INIS)

Sinha, R.; Verma, R.; Rajesh, A.; Richards, C.J.

2006-01-01

Aim: Although magnetic resonance (MR) imaging is widely used for rectal cancer staging, many centres in the UK perform computed tomography (CT) for staging rectal cancer at present. Furthermore in a small proportion of cases contraindications to MR imaging may lead to staging using CT. The purpose of this study was to evaluate the accuracy of current generation multidetector row CT (MDCT) in local staging of rectal cancer. In particular the accuracy of multiplanar (MPR) versus axial images in the staging of rectal cancer was assessed. Material and methods: Sixty-nine consecutive patients were identified who had undergone staging of rectal cancer on CT. The imaging data were reviewed as axial images and then as MPR images (coronal and sagittal) perpendicular and parallel to the tumour axis. CT staging on axial and MPR images was then compared to histopathological staging. Results: MPR images detected more T4 and T3 stage tumours than axial images alone. The overall accuracy of T-staging on MPR images was 87.1% versus 73.0% for axial images alone. The overall accuracy of N staging on MPR versus axial images was 84.8% versus 70.7%. There was a statistically significant difference in the staging of T3 tumours between MPR and axial images (p < 0.001). Conclusion: Multidetector row CT has high accuracy for local staging of rectal cancer. Addition of MPR images to standard axial images provides higher accuracy rates for T and N staging of rectal cancer than axial images alone

Patient-related factors influencing detectability of coronary arteries in 320-row CT angiography in infants with complex congenital heart disease.

Science.gov (United States)

Yamasaki, Yuzo; Kawanami, Satoshi; Kamitani, Takeshi; Sagiyama, Koji; Shin, Seitaro; Hino, Takuya; Nagata, Hazumu; Yabuuchi, Hidetake; Nagao, Michinobu; Honda, Hiroshi

2018-05-05

To investigate the performance of second-generation 320-row computed tomographic (CT) angiography (CTA) in detecting coronary arteries and identify factors influencing visibility of the coronary arteries in infants with complex congenital heart disease (CHD). Data of 60 infants (aged 0-2 years, median 2 months) with complex CHD who underwent examination using 320-row CTA with low-dose prospective electrocardiogram-triggered volume target scanning were reviewed. The coronary arteries of each infant were assessed using a 0-4-point scoring system based on the number of coronary segments with a visible course. Clinical parameters, the CT value in the ascending aorta, image noise, and the radiation dose were subjected to univariate and multivariate analyses. The mean coronary score for all examinations was 2.6 ± 1.5 points. The mean attenuation in the ascending aorta was 306.7 ± 66.2 HU and the mean standard deviation was 21.7 ± 4.4. The mean effective radiation dose was 1.27 ± 0.39 mSv. Multivariate regression analysis showed significant correlations between coronary score and body weight (p < 0.05) and between coronary score and the CT value in the ascending aorta (p < 0.02). Second-generation 320-row CTA with prospective electrocardiogram-triggered volume target scanning and hybrid iterative reconstruction allows good visibility of the coronary arteries in infants with complex CHD. Body weight and the CT value in the ascending aorta are important factors influencing the visibility of the coronary arteries in infants.

Multidetector Row CT Detection of a Patent Foramen Ovale Causing Neurologic Deficits in an Adolescent: A Case Report

Energy Technology Data Exchange (ETDEWEB)

Lee, Jung Bin [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Kim, Dong Hun; Oh, Jae Hee [Dept. of Radiology, Chosun University College of Medicine, Gwangju (Korea, Republic of); Seo, Hye Sun [Dept. of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Suk, Eun Ha [Dept. of Anesthesiology and Pain Medicine, Asan Medical Center, Seoul (Korea, Republic of)

2012-02-15

A patent foramen ovale (PFO) is a persisting fetal circulation structural abnormality that can cause neurologic deficits such as migraine and cryptogenic stroke. Here we report a case of PFO diagnosed by cardiac multidetector row CT in an adolescent male with chronic migraine and stroke.

Multidetector Row CT Detection of a Patent Foramen Ovale Causing Neurologic Deficits in an Adolescent: A Case Report

International Nuclear Information System (INIS)

Lee, Jung Bin; Kim, Dong Hun; Oh, Jae Hee; Seo, Hye Sun; Suk, Eun Ha

2012-01-01

A patent foramen ovale (PFO) is a persisting fetal circulation structural abnormality that can cause neurologic deficits such as migraine and cryptogenic stroke. Here we report a case of PFO diagnosed by cardiac multidetector row CT in an adolescent male with chronic migraine and stroke.

Integrated cardio-thoracic imaging with ECG-Gated 64-slice multidetector-row CT: initial findings in 133 patients

International Nuclear Information System (INIS)

Salem, Randa; Remy-Jardin, Martine; Delhaye, Damien; Khalil, Chadi; Teisseire, Antoine; Remy, Jacques; Delannoy-Deken, Valerie; Duhamel, Alain

2006-01-01

The purpose of this study was to investigate the possibility of assessing the underlying respiratory disease as well as cardiac function during ECG-gated CT angiography of the chest with 64-slice multidetector-row CT (MDCT). One hundred thirty-three consecutive patients in sinus rhythm with known or suspected ventricular dysfunction underwent an ECG-gated CT angiographic examination of the chest without β-blockers using the following parameters: (1) collimation: 32 x 0.6 mm with z-flying focal spot for the acquisition of 64 overlapping 0.6-mm slices (Sensation 64; Siemens); rotation time: 0.33 s; pitch: 0.3; 120 kV; 200 mAs; ECG-controlled dose modulation (ECG-pulsing) and (2) 120 ml of a 35% contrast agent. Data were reconstructed: (1) to evaluate the underlying respiratory disease (1-mm thick lung and mediastinal scans reconstructed at 55% of the R-R interval; i.e., ''morphologic scans'') and (2) to determine right (RVEF) and left (LVEF) ventricular ejection fractions (short-axis systolic and diastolic images; Argus software; i.e., ''functional scans''). The mean heart rate was 73 bpm (range: 42-120) and the mean scan time was 18.11±2.67 s (range: 10-27). A total of 123 examinations (92%) had both lung and mediastinal images rated as diagnostic scans, whereas 10 examinations (8%) had non-diagnostic images altered by the presence of respiratory-motion artifacts (n=4) or cyclic artifacts related to the use of a pitch value of 0.3 in patients with a very low heart rate during data acquisition (n=6). Assessment of right and left ventricular function was achievable in 124 patients (93%, 95% CI: 88-97%). For these 124 examinations, the mean RVEF was 46.10% (±9.5; range: 20-72) and the mean LVEF was 58.23% (±10.88; range: 20-83). In the remaining nine patients, an imprecise segmentation of the right and left ventricular cavities was considered as a limiting factor for precise calculation of end-systolic and end-diastolic ventricular volumes. The mean (±SD) DLP

Multidetector row CT of the brain and carotid artery: a correlative analysis

International Nuclear Information System (INIS)

Saba, L.; Montisci, R.; Sanfilippo, R.; Mallarini, G.

2009-01-01

Aim: To evaluate the association between types of carotid plaque, the presence of prior ischaemic events detectable with CT, and patient's symptoms. Materials and methods: Between January 2004 and May 2006, 112 patients were evaluated using multidetector row computed tomography angiography (MDCTA) of the carotid arteries and computed tomography (CT) of the brain. Carotid arteries were categorized by evaluating the degree of stenosis according to North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria, the type of plaque, and the presence of plaque ulceration. The brain was assessed via CT for the presence, type, and position of lesions. Chi-square tests, Student's t test, and simple logistic regression analysis were performed and the Cohen kappa test was applied for interobserver variability measurement. Results: The Chi-square test indicated a statistically significant association between the presence of fatty plaques (p = 0.005) and CT-detectable lesions in the brain (p = 0.004). Moreover, the number of patients with CT-detectable brain lesions was greater in patients with >70% stenosis than in those with 70% stenosis and symptoms (p = 0.041), and an inverse association between calcified plaque and symptoms (p = 0.009). Conclusion: MDCTA allows adequate evaluation of the type of plaque. The results of the present study indicate that there is an association between cerebral lesions, symptoms, and fatty plaque in the carotid artery. The degree of stenosis also correlated with cerebral lesions and symptoms. According to the obtained data, the type of carotid plaque should be included among primary parameters in the classification of patients' risk class.

Chronic thromboembolic pulmonary hypertension: Evaluation with 64-detector row CT versus digital substraction angiography

Energy Technology Data Exchange (ETDEWEB)

Reichelt, Angela [Department of Diagnostic Radiology, Hannover Medical School, Carl Neuberg Str. 1, 30625 Hannover (Germany)], E-mail: Reichelt.Angela@mh-hannover.de; Hoeper, Marius M. [Department of Respiratory Medicine, Hannover Medical School (Germany); Galanski, Michael [Department of Diagnostic Radiology, Hannover Medical School, Carl Neuberg Str. 1, 30625 Hannover (Germany); Keberle, Marc [Department of Diagnostic Radiology and Nuclear Medicine, Bruederkrankenhaus St. Josef Paderborn (Germany)

2009-07-15

The aim of the study was to evaluate the role of 64-row CT in the diagnostic workup of patients with chronic thromboembolic pulmonary hypertension (CTEPH) using digital substraction angiography (DSA) as the method of diagnostic reference. CT and DSA studies of 27 patients (54 main, 162 lobar and 540 segmental arteries) with a clinical suspicion of CTEPH were included in this retrospective and blinded analysis. Axial images and multiplanar thin maximum intensity projections (MIPs) (3 mm) were consequently used for exact image interpretation whereas additional reconstructed thick MIPs gave an overview of the entire vascular tree comparable to DSA. Sensitivity and specificity of CT regarding CTEPH-related pathological changes in general were 98.3% and 94.8% at main/lobar level and 94.1% and 92.9% at segmental level, respectively. Sensitivity and specificity of CT regarding the different pathological criteria of CTEPH (complete obstruction, intimal irregularities, bands and webs, indirect signs) were 88.9-100% and 96.1-100% at main/lobar level and 84.3-90.5% and 92-98.7% at segmental level, respectively. Our results show that CT is an accurate and reliable non-invasive alternative to conventional DSA in the diagnostic workup in patients with CTEPH.

Chronic thromboembolic pulmonary hypertension: Evaluation with 64-detector row CT versus digital substraction angiography

International Nuclear Information System (INIS)

Reichelt, Angela; Hoeper, Marius M.; Galanski, Michael; Keberle, Marc

2009-01-01

The aim of the study was to evaluate the role of 64-row CT in the diagnostic workup of patients with chronic thromboembolic pulmonary hypertension (CTEPH) using digital substraction angiography (DSA) as the method of diagnostic reference. CT and DSA studies of 27 patients (54 main, 162 lobar and 540 segmental arteries) with a clinical suspicion of CTEPH were included in this retrospective and blinded analysis. Axial images and multiplanar thin maximum intensity projections (MIPs) (3 mm) were consequently used for exact image interpretation whereas additional reconstructed thick MIPs gave an overview of the entire vascular tree comparable to DSA. Sensitivity and specificity of CT regarding CTEPH-related pathological changes in general were 98.3% and 94.8% at main/lobar level and 94.1% and 92.9% at segmental level, respectively. Sensitivity and specificity of CT regarding the different pathological criteria of CTEPH (complete obstruction, intimal irregularities, bands and webs, indirect signs) were 88.9-100% and 96.1-100% at main/lobar level and 84.3-90.5% and 92-98.7% at segmental level, respectively. Our results show that CT is an accurate and reliable non-invasive alternative to conventional DSA in the diagnostic workup in patients with CTEPH.

Bronchial and non-bronchial systemic arteries: value of multidetector CT angiography in diagnosis and angiographic embolisation feasibility analysis

International Nuclear Information System (INIS)

Lin, Yuning; Chen, Ziqian; Yang, Xizhang; Zhong, Qun; Zhang, Hongwen; Yang, Li; Xu, Shangwen; Li, Hui

2013-01-01

The aim of this study is to evaluate the diagnostic performance of multidetector CT angiography (CTA) in depicting bronchial and non-bronchial systemic arteries in patients with haemoptysis and to assess whether this modality helps determine the feasibility of angiographic embolisation. Fifty-two patients with haemoptysis between January 2010 and July 2011 underwent both preoperative multidetector CTA and digital subtraction angiography (DSA) imaging. Diagnostic performance of CTA in depicting arteries causing haemoptysis was assessed on a per-patient and a per-artery basis. The feasibility of the endovascular treatment evaluated by CTA was analysed. Sensitivity, specificity, and positive and negative predictive values for those analyses were determined. Fifty patients were included in the artery-presence-number analysis. In the per-patient analysis, neither CTA (P=0.25) nor DSA (P=1.00) showed statistical difference in the detection of arteries causing haemoptysis. The sensitivity, specificity, and positive and negative predictive values were 94%, 100%, 100%, and 40%, respectively, for the presence of pathologic arteries evaluated by CTA, and 98%, 100%, 100%, and 67%, respectively, for DSA. On the per-artery basis, CTA correctly identified 97% (107/110). Fifty-two patients were included in the feasibility analysis. The performance of CTA in predicting the feasibility of angiographic embolisation was not statistically different from the treatment performed (P=1.00). The sensitivity, specificity, and positive and negative predictive values were 96%, 80%, 98% and 67%, respectively, for CTA. Multidetector CTA is an accurate imaging method in depicting the presence and number of arteries causing haemoptysis. This modality is also useful for determining the feasibility of angiographic embolisation for haemoptysis.

SimDoseCT: dose reporting software based on Monte Carlo simulation for a 320 detector-row cone-beam CT scanner and ICRP computational adult phantoms

Science.gov (United States)

Cros, Maria; Joemai, Raoul M. S.; Geleijns, Jacob; Molina, Diego; Salvadó, Marçal

2017-08-01

This study aims to develop and test software for assessing and reporting doses for standard patients undergoing computed tomography (CT) examinations in a 320 detector-row cone-beam scanner. The software, called SimDoseCT, is based on the Monte Carlo (MC) simulation code, which was developed to calculate organ doses and effective doses in ICRP anthropomorphic adult reference computational phantoms for acquisitions with the Aquilion ONE CT scanner (Toshiba). MC simulation was validated by comparing CTDI measurements within standard CT dose phantoms with results from simulation under the same conditions. SimDoseCT consists of a graphical user interface connected to a MySQL database, which contains the look-up-tables that were generated with MC simulations for volumetric acquisitions at different scan positions along the phantom using any tube voltage, bow tie filter, focal spot and nine different beam widths. Two different methods were developed to estimate organ doses and effective doses from acquisitions using other available beam widths in the scanner. A correction factor was used to estimate doses in helical acquisitions. Hence, the user can select any available protocol in the Aquilion ONE scanner for a standard adult male or female and obtain the dose results through the software interface. Agreement within 9% between CTDI measurements and simulations allowed the validation of the MC program. Additionally, the algorithm for dose reporting in SimDoseCT was validated by comparing dose results from this tool with those obtained from MC simulations for three volumetric acquisitions (head, thorax and abdomen). The comparison was repeated using eight different collimations and also for another collimation in a helical abdomen examination. The results showed differences of 0.1 mSv or less for absolute dose in most organs and also in the effective dose calculation. The software provides a suitable tool for dose assessment in standard adult patients undergoing CT

Mesenteric Castleman's disease: ultrasound, computed tomography and angiographic appearance

International Nuclear Information System (INIS)

Malara, F.A.; Price, D.; Fabiny

2000-01-01

The localized form of Castleman's disease is rare, and a mesenteric location is particularly unusual. A case of an asymptomatic young woman having the hyaline vascular type is presented and the ultrasound, computed tomography (CT) and angiographic features of the condition are demonstrated. Copyright (1999) Blackwell Science Pty Ltd

Radiation Dose and Image Quality from Coronary Angiography in 320-Detecor Row CT

International Nuclear Information System (INIS)

Thanomphudsa, J.; Krisanachinda, A.; Tumkosit, M.

2012-01-01

Introduction: Coronary Computed Tomography Angiography examinations are increasing rapidly. New Computed Tomography has been developed to improve image quality with the patient dose reduction. The purpose of this study is to evaluate radiation dose and image quality of Coronary Computed Tomography Angiography in patients using 320-detector row CT. Methods: Forty-one patients referred for cardiac CT examinations at King Chulalongkorn Memorial Hospital were included in this study. All coronary computed tomographic angiography (CCTA) examinations were performed on the 320-detector row CT, Toshiba Aquilion One. Scanning protocol was investigated on dose estimates and image quality. Patients were scanned base on heart rate (HR) by HR 75 bpm use retrospective with dose modulation. Scanning parameters, kVp, mAs, HR, BMI, CTDIvol(mGy) and DLP(mGy.cm), were recorded to study the factors affecting the image quality and patient dose. And mA and kVp setting depend on BMI of the patient. Effective dose is calculated from DLP using specific conversion factor. The image quality was evaluated in 4 vessels by two radiologists. Noise assessment was also studied quantitatively. Results: The patient effective dose in prospective gating 70-80% was 3.6 ± 0.9 mSv, prospective gating 30-80% (1R-R) was 6.3 ± 1.9 mSv, and 30-80% (2R-R) was 10.8 ± 1.8 mSv and in retrospective with tube current modulation was 12.1± 7.7 mSv. Image noise was highest in PGT 70-80% 1R-R and decreased in RGT with tube current modulation, PGT 30-80% 1R-R and lowest in PGT 30-80% 2 R-R. And overall qualitative image quality was mostly good to excellent score. Discussion: The heart rate, heart rate variability and disease of the patient are affecting in the radiation dose and image quality so the suitable acquisition protocol used could be necessary. the effective dose and the image noise for the image quality. (author)

Blunt renal trauma: comparison of contrast-enhanced CT and angiographic findings and the usefulness of transcatheter arterial embolization

International Nuclear Information System (INIS)

Kitase, M.; Mizutani, M.; Tomita, H.; Kono, T.; Sugie, C.; Shibamoto, Y.

2007-01-01

Full text: Background: The purpose of this study was to evaluate the role of contrast-enhanced CT and the usefulness of super selective embolization therapy in the management of arterial damage in patients with severe blunt renal trauma. Patients and Methods: Nine cases of severe renal trauma were evaluated. In all cases, we compared contrast enhanced CT findings with angiographic findings, and performed transcatheter arterial embolization (TAE) in six of them with microcoils and gelatin sponge particles. Morphological changes in the kidney and site of infarction after TAE were evaluated on follow-up CT Chronological changes in blood biochemistry findings after injury, degree of anemia and renal function were investigated. Adverse effects or complications such as duration of hematuria, fever, abdominal pain, renovascular hypertension and abscess formation were also evaluated. Results: The CT finding of extravasation was a reliable sign of active bleeding and useful for determining the indication of TAE. In all cases, bleeding was effectively controlled with super selective embolization. There was minimal procedure-related loss of renal tissue. None of the patients developed abscess, hypertension or other complications. Conclusions: In blunt renal injury, contrast-enhanced CT was useful for diagnosing arterial hemorrhage. Arterial bleeding may produce massive hematoma and TAE was a useful treatment for such cases. By using selective TAE for a bleeding artery, it was possible to minimize renal parenchymal damage, with complications of TAE rarely seen. (author)

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.)

3D automatic exposure control for 64-detector row CT: Radiation dose reduction in chest phantom study

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Keiko, E-mail: palm_kei@yahoo.co.jp [Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Department of Radiology, Yamanashi University, Shimokato, Yamanashi (Japan); Ohno, Yoshiharu; Koyama, Hisanobu; Kono, Atsushi [Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Inokawa, Hiroyasu [Toshiba Medical Systems, Ohtawara, Tochigi (Japan); Onishi, Yumiko [Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Nogami, Munenobu [Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Image-Based Medicine, Institute of Biomedical Research and Innovation, Kobe, Hyogo (Japan); Takenaka, Daisuke [Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Araki, Tsutomu [Department of Radiology, Yamanashi University, Shimokato, Yamanashi (Japan); Sugimura, Kazuro [Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan)

2011-03-15

Purpose: The purpose of this study was to determine the utility of three-dimensional (3D) automatic exposure control (AEC) for low-dose CT examination in a chest phantom study. Materials and methods: A chest CT phantom including simulated focal ground-glass opacities (GGOs) and nodules was scanned with a 64-detector row CT with and without AEC. Performance of 3D AEC included changing targeted standard deviations (SDs) of image noise from scout view. To determine the appropriate targeted SD number for identification, the capability of overall identification with the CT protocol adapted to each of the targeted SDs was compared with that obtained with CT without AEC by means of receiver operating characteristic analysis. Results: When targeted SD values equal to or higher than 250 were used, areas under the curve (Azs) of nodule identification with CT protocol using AEC were significantly smaller than that for CT protocol without AEC (p < 0.05). When targeted SD numbers at equal to or more than 180 were adapted, Azs of CT protocol with AEC had significantly smaller than that without AEC (p < 0.05). Conclusion: This phantom study shows 3D AEC is useful for low-dose lung CT examination, and can reduce the radiation dose while maintaining good identification capability and good image quality.

Spiral CT during pharmacoangiography with angiotensin II in patients with pancreatic disease. Technique and diagnostic efficacy

Energy Technology Data Exchange (ETDEWEB)

Kuroda, C.; Mihara, N.; Hosomi, N.; Inoue, E.; Fujita, M. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Diagnostic Radiology; Ohigashi, H.; Ishikawa, O. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Surgery; Nakaizumi, A. [Osaka Medical Center for Cancer and Cardiovascular Deseases (Japan). Dept. of Internal Medicine; Ishiguro, S. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Pathology

1998-03-01

Purpose: To compare the diagnostic efficacy of pancreatic pharmacoangiographic CT using angiotensin II with conventional angiographic CT. Material and Methods: Eighteen patients with space-occupying pancreatic disease were examined in this study. Pharmacoangiographic CT was performed with a 1-3-{mu}/6-ml solution of angiotensin II injected through a catheter into the celiac artery during spiral CT. Results: In 17 of the 18 (94%) patients, the area of pancreatic parenchymal enhancement was the same or larger at pharmacoangiographic CT than at conventional angiographic CT. The attenuation value of the pancreatic parenchyma was significantly increased at pharmacoangiographic CT (p=0.0010). Although the attenuation value of tumors was also increased on images obtained after the injection of angiotensin II, the tumor-to-pancreas contrast was significantly greater at pharmacoangiographic CT (p=0.0479). The mean differences in attenuation between tumor and pancreas at angiographic CT with and without angiotensin II were respectively 182 HU and 115 HU. Conclusion: Pharmacoangiographic CT with angiotensin II proved superior to conventional angiographic CT in the diagnosis of pancreatic disease. We therefore recommend it as a supplementary technique at the angiographic examination of patients with suspected pancreatic tumor. (orig.).

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.)

320-Multidetector row whole-head dynamic subtracted CT angiography and whole-brain CT perfusion before and after carotid artery stenting: Technical note

International Nuclear Information System (INIS)

San Millan Ruiz, Diego; Murphy, Kieran; Gailloud, Philippe

2010-01-01

Introduction: Multidetector CT (MDCT) is increasingly used for the investigation of neurovascular disorders, but restricted z-axis coverage (3.2 cm for 64-MDCT) currently limits perfusion to a small portion of the brain close to the circle of Willis, and precludes dynamic angiographic appreciation of the entire brain circulation. We illustrate the clinical potential of recently developed 320-MDCT extending the z-axis coverage to 16 cm in a patient with symptomatic carotid artery stenosis. Methods: In a 74-year-old patient presenting with critical symptomatic stenosis of the left CCA, pre- and post-carotid artery stenting whole-head subtracted dynamic MDCT angiography and perfusion were obtained in addition to CT angiography of the supra-aortic trunks. Both whole-head subtracted MDCT angiography and perfusion demonstrated delayed left ICA circulation, which normalized after carotid stenting. Discussion: 320-MDCT offers unprecedented z-axis coverage allowing for whole-brain perfusion and subtracted dynamic angiography of the entire intracranial circulation. These innovations can consolidate the role of MDCT as a first intention imaging technique for cerebrovascular disorders, in particular for the acute management of stroke.

Bronchial and non-bronchial systemic arteries: value of multidetector CT angiography in diagnosis and angiographic embolisation feasibility analysis.

Science.gov (United States)

Lin, Yuning; Chen, Ziqian; Yang, Xizhang; Zhong, Qun; Zhang, Hongwen; Yang, Li; Xu, Shangwen; Li, Hui

2013-12-01

The aim of this study is to evaluate the diagnostic performance of multidetector CT angiography (CTA) in depicting bronchial and non-bronchial systemic arteries in patients with haemoptysis and to assess whether this modality helps determine the feasibility of angiographic embolisation. Fifty-two patients with haemoptysis between January 2010 and July 2011 underwent both preoperative multidetector CTA and digital subtraction angiography (DSA) imaging. Diagnostic performance of CTA in depicting arteries causing haemoptysis was assessed on a per-patient and a per-artery basis. The feasibility of the endovascular treatment evaluated by CTA was analysed. Sensitivity, specificity, and positive and negative predictive values for those analyses were determined. Fifty patients were included in the artery-presence-number analysis. In the per-patient analysis, neither CTA (P = 0.25) nor DSA (P = 1.00) showed statistical difference in the detection of arteries causing haemoptysis. The sensitivity, specificity, and positive and negative predictive values were 94%, 100%, 100%, and 40%, respectively, for the presence of pathologic arteries evaluated by CTA, and 98%, 100%, 100%, and 67%, respectively, for DSA. On the per-artery basis, CTA correctly identified 97% (107/110). Fifty-two patients were included in the feasibility analysis. The performance of CTA in predicting the feasibility of angiographic embolisation was not statistically different from the treatment performed (P = 1.00). The sensitivity, specificity, and positive and negative predictive values were 96%, 80%, 98% and 67%, respectively, for CTA. Multidetector CTA is an accurate imaging method in depicting the presence and number of arteries causing haemoptysis. This modality is also useful for determining the feasibility of angiographic embolisation for haemoptysis. © 2013 The Authors. Journal of Medical Imaging and Radiation Oncology © 2013 The Royal Australian and New Zealand College of Radiologists.

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

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.

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

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.

Usefulness of multidetector-row computed tomography (MD-CT) for diagnosis and evaluation of cardiovascular anomalies in infants

International Nuclear Information System (INIS)

Kani, Hiroyuki; Narabayashi, Isamu; Tanikake, Masato; Matsuki, Mitsuru; Uesugi, Yasuo

2005-01-01

We examined the effectiveness of multidetector-row CT (MD-CT) in the diagnosis and evaluation of cardiovascular anomalies in infants. MD-CT was performed 34 times on 21 patients with cardiovascular anomalies. We performed three evaluations: 1) The assessment of the specificity of MD-CT in detecting the morphological features of cardiovascular anomalies. 2) The diameters of aortae with coronary artery (CoA), and the diameters of pulmonary artery, measured by using MD-CT were compared with those by angiography. 3) The amount of exposure to radiation was measured. 1) MD-CT can detect CoA, pulmonary arteriovenous anomalies among extracardiac anomalies in all the patients. The diagnostic accuracy for intracardiac anomalies was poor as only six of the 15 anomalies could be accurately diagnosed. 2) The diameters of aortae and pulmonary artery obtained using MD-CT showed a good correlation with those obtained using arteriography (r=0.97, 0.95). 3) The average dose-length product was 269.2 mGy·cm. And the average effective dose was 5.1 mSv. MD-CT is not suitable for the evaluation of intracardiac anomalies, but is extremely effective in the evaluation of extracardiac major vascular anomalies. On the basis of the amount of information and noninvasive nature, MD-CT should be used first before angiography. (author)

The comparison of coronary arteries imaging features between Uygur and Han populations in Xinjiang with 64-slice spiral CT

International Nuclear Information System (INIS)

Pan Cunxue; Zhao Yanping; Liu Wenya; Wang Haitao; Dang Jun; Yang Wen; Sun Yajing; Li Xiaoyu

2010-01-01

Objective: To analyze the imaging findings of coronary angiography using 64-slice row CT and investigate the difference of coronary artery's morphological characteristics between Uygur and Han populations. Methods: A retrospective study was made to coronary CT angiographic images of 88 Uygur cases matched with 88 Han cases. The data were analyzed with X 2 test and paired Wilcoxon test. Results: The coronary CT angiographic findings were different between Uygur population and Han population in the following aspects: there were 62, 18, and 8 cases with the left coronary artery originating from intra-sinus, para-sinus and extra-sinus location respectively in Uygur population, while there were 73, 14, and 8 cases in Han population respectively (t=8319, P 2 =5.8381, P 2 =5.1948, P<0.05). The cases with LCA variations were 28 and 49 cases in the two populations respectively (t=2692, P<0.05) and the number with RCA variations were 33 and 27 cases in the two populations respectively (t=968, P<0.05). Conclusions: There are lots of differences of the coronary artery morphology between the Uygur and Han populations. Firstly, these differences may be related to different patterns in coronary angiography. Secondly, these differences may be related to differences between Uygur and Han populations in the incidence and severity of coronary heart disease. (authors)

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

Impact of imaging quality of change pitch on coronary CTA with 64-detector row CT

International Nuclear Information System (INIS)

Li Xiang; Jin Chaolin; Zhang Shutong

2009-01-01

Objective: To investigate the impact of imaging quality of pitch on coronary CT angiography (CTA) with 64-detector row CT. Methods: 566 patients were divided into four groups according to heart rate (≤ 50, 51 ∼ 70, 71 ∼ 80 and ≥ 80 bpm). Three dimensional reconstructions were used such as volume rendering (VR), maximum intensity projection(MIP) and curved planar reformation (CPR). Each group was divided into control group and experimential group randomly, using normal pitch and revised pitch respectively, and the imaging quality and influencing factors were analyzed among the four groups. Results: There was significant difference in imaging quality among the four groups (P < 0.05). Each group had difference in imaging quality with normal pitch and revised pitch. Conclusions: The revised pitch helps to improve the imaging quality and meet the demand of diagnosis. (authors)

Whole brain CT perfusion deficits using 320-detector-row CT scanner in TIA patients are associated with ABCD2 score.

Science.gov (United States)

Mehta, Bijal K; Mustafa, Ghulam; McMurtray, Aaron; Masud, Mohammed W; Gunukula, Sameer K; Kamal, Haris; Kandel, Amit; Beltagy, Abdelrahman; Li, Ping

2014-01-01

Transient ischemic attacks (TIA) are cerebral ischemic events without infarction. The uses of CT perfusion (CTP) techniques such as cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT) and cerebral blood flow (CBF) provide real time data about ischemia. It has been shown that CTP changes occur in less sensitive CTP scanners in patients with TIA. Larger detector row CTP (whole brain perfusion studies) may show that CTP abnormalities are more prevalent than previously noted. It is also unclear if these changes are associated with TIA severity. To demonstrate that TIA patients are associated with perfusion deficits using whole brain 320-detector-row CT perfusion, and to determine an association between ABCD2 score and perfusion deficit using whole brain perfusion. We retrospectively reviewed all TIA patients for CTP deficits from 2008-2010. Perfusion imaging was reviewed at admission; and it was determined if a perfusion deficit was present along with vascular territory involved. Of 364 TIA patients, 62 patients had CTP deficits. The largest group of patients had MCA territory involved with 48 of 62 patients (77.42%). The most common perfusion abnormality was increased TTP with 46 patients (74.19%). The ABCD2 score was reviewed in association with perfusion deficit. Increased age >60, severe hypertension (>180/100 mmHg), patients with speech abnormalities, and duration of symptoms >10 min were associated with a perfusion deficit but history of diabetes or minimal/moderate hypertension (140/90-179/99 mmHg) was not. There was no association between motor deficit and perfusion abnormality. Perfusion deficits are found in TIA patients using whole brain CTP and associated with components of the ABCD2 score.

[Multidisciplinary protocol for computed tomography imaging and angiographic embolization of splenic injury due to trauma: assessment of pre-protocol and post-protocol outcomes].

Science.gov (United States)

Koo, M; Sabaté, A; Magalló, P; García, M A; Domínguez, J; de Lama, M E; López, S

2011-11-01

To assess conservative treatment of splenic injury due to trauma, following a protocol for computed tomography (CT) and angiographic embolization. To quantify the predictive value of CT for detecting bleeding and need for embolization. The care protocol developed by the multidisciplinary team consisted of angiography with embolization of lesions revealed by contrast extravasation under CT as well as embolization of grade III-V injuries observed, or grade I-II injuries causing hemodynamic instability and/or need for blood transfusion. We collected data on demographic variables, injury severity score (ISS), angiographic findings, and injuries revealed by CT. Pre-protocol and post-protocol outcomes were compared. The sensitivity and specificity of CT findings were calculated for all patients who required angiographic embolization. Forty-four and 30 angiographies were performed in the pre- and post-protocol periods, respectively. The mean (SD) ISSs in the two periods were 25 (11) and 26 (12), respectively. A total of 24 (54%) embolizations were performed in the pre-protocol period and 28 (98%) after implementation of the protocol. Two and 7 embolizations involved the spleen in the 2 periods, respectively; abdominal laparotomies numbered 32 and 25, respectively, and 10 (31%) vs 4 (16%) splenectomies were performed. The specificity and sensitivity values for contrast extravasation found on CT and followed by embolization were 77.7% and 79.5%. The implementation of this multidisciplinary protocol using CT imaging and angiographic embolization led to a decrease in the number of splenectomies. The protocol allows us to take a more conservative treatment approach.

Inter- and intrascanner variability of pulmonary nodule volumetry on low-dose 64-row CT: an anthropomorphic phantom study

Science.gov (United States)

Xie, X; Willemink, M J; Zhao, Y; de Jong, P A; van Ooijen, P M A; Oudkerk, M; Greuter, M J W

2013-01-01

Objective: To assess inter- and intrascanner variability in volumetry of solid pulmonary nodules in an anthropomorphic thoracic phantom using low-dose CT. Methods: Five spherical solid artificial nodules [diameters 3, 5, 8, 10 and 12 mm; CT density +100 Hounsfield units (HU)] were randomly placed inside an anthropomorphic thoracic phantom in different combinations. The phantom was examined on two 64-row multidetector CT (64-MDCT) systems (CT-A and CT-B) from different vendors with a low-dose protocol. Each CT examination was performed three times. The CT examinations were evaluated twice by independent blinded observers. Nodule volume was semi-automatically measured by dedicated software. Interscanner variability was evaluated by Bland–Altman analysis and expressed as 95% confidence interval (CI) of relative differences. Intrascanner variability was expressed as 95% CI of relative variation from the mean. Results: No significant difference in CT-derived volume was found between CT-A and CT-B, except for the 3-mm nodules (pvolumetry of artificial pulmonary nodules between 5 mm and 12 mm in diameter. Inter- and intrascanner variability decreases at a larger nodule size to a maximum of 4.9% for ≥8 mm nodules. Advances in knowledge: The commonly accepted cut-off of 25% to determine nodule growth has the potential to be reduced for ≥8 mm nodules. This offers the possibility of reducing the interval for repeated CT scans in lung cancer screenings. PMID:23884758

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

Characteristics of images of angiographically proven normal coronary arteries acquired by adenosine-stress thallium-201 myocardial perfusion SPECT/CT-IQ[Symbol: see text]SPECT with CT attenuation correction changed stepwise.

Science.gov (United States)

Takahashi, Teruyuki; Tanaka, Haruki; Kozono, Nami; Tanakamaru, Yoshiki; Idei, Naomi; Ohashi, Norihiko; Ohtsubo, Hideki; Okada, Takenori; Yasunobu, Yuji; Kaseda, Shunichi

2015-04-01

Although several studies have shown the diagnostic and prognostic value of CT-based attenuation correction (AC) of single photon emission computed tomography (SPECT) images for diagnosing coronary artery disease (CAD), this issue remains a matter of debate. To clarify the characteristics of CT-AC SPECT images that might potentially improve diagnostic performance, we analyzed images acquired using adenosine-stress thallium-201 myocardial perfusion SPECT/CT equipped with IQ[Symbol: see text]SPECT (SPECT/CT-IQ[Symbol: see text]SPECT) from patients with angiographically proven normal coronary arteries after changing the CT attenuation correction (CT-AC) in a stepwise manner. We enrolled 72 patients (Male 36, Female 36) with normal coronary arteries according to findings of invasive coronary angiography or CT-angiography within three months after a SPECT/CT study. Projection images were reconstructed at CT-AC values of (-), 40, 60, 80 and 100 % using a CT number conversion program according to our definition and analyzed using polar maps according to sex. CT attenuation corrected segments were located from the mid- and apical-inferior spread through the mid- and apical-septal regions and finally to the basal-anterior and basal- and mid-lateral regions in males, and from the mid-inferior region through the mid-septal and mid-anterior, and mid-lateral regions in females as the CT-AC values increased. Segments with maximal mean counts shifted from the apical-anterior to mid-anterolateral region under both stress and rest conditions in males, whereas such segments shifted from the apical-septal to the mid-anteroseptal region under both stress and rest conditions in females. We clarified which part of the myocardium and to which degree CT-AC affects it in adenosine-stress thallium-201 myocardial perfusion SPECT/CT-IQ[Symbol: see text]SPECT images by changing the CT-AC value stepwise. We also identified sex-specific shifts of segments with maximal mean counts that changed as

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

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

Coronary artery imaging with 64-slice spiral CT in atrial fibrillation patients: initial experience

International Nuclear Information System (INIS)

Zhou Xuhui; Yan Chaogui; Xie Hongbo; Li Xiangmin; Li Ziping; Meng Quanfei; Chen Xing

2008-01-01

Objective: To discuss the clinical value of coronary artery imaging using 64-slice spiral CT in patient with atrial fibrillation. Methods: The images of 31 patients with atrial fibrillation who underwent contrast-enhanced CT coronary angiography were evaluated. The presence of stenosis on each segment of coronary arteries was recorded and their degree of stenosis was measured using the vessel analysis software. Ten patients additionally underwent conventional coronary angiography. The results of conventional coronary angiography were compared with CT coronary angiography of the 10 patients. Results: Image reconstruction was based on absolute timing. The image quality of 364 coronary vessel segments on the images from 31 patients was evaluated and defined as excellent, fine, moderate or poor. The image quality was excellent, fine, moderate and poor in 85, 41, 5, and 8 vessel segments respectively in patient group with heart rate between 47 beat per minent (bpm) and 69 bpm; and in 63, 16, 13, and 15 vessel segments respectively in patent group with heart rate between 70 bpm and 79 bpm;and in 46, 25, 23, and 24 vessel segments in patient group with heart rate between 80 bpm and 105 bpm. There was significant difference among the three patient groups (H=22.08, P<0.01). Comparison was carried out between CT angiographic findings and conventional angiographic findings of the 125 segments of the coronary arteries in the 10 patients who underwent conventional coronary angiography. The sensitivity and specificity of CT angiography for diagnosing vessel with significant coronary stenosis (≥50% narrowing) was 85.0% (17/20) and 95.2% (100/105), respectively. Positive predictive value was 77.3% (17/22), and negative predictive value was 97.1% (100/103). Coronary CTA underestimated the lesions of 3 vessel segments and overestimated the lesions of 5 vessel segments. Conclusion: Coronary artery imaging with 64-slice row CT had clinical value for patients with atrial fibrillation

Association between the mean CT value on a scout view and the dependent mA selection method in coronary artery imaging on 64-row multi-slice spiral CT

International Nuclear Information System (INIS)

Gao Jianhua; Li Tao; Mi Fengtang; Li Na; Cui Ying; Dai Ruping; Li Jianying

2009-01-01

Objective: To characterize the association between the mean CT value on a scout view and the dependent mA selection method, and to evaluate the clinical value of a mA selection method based on scout view mean CT value in obtaining individualized scan protocol and consistent image quality for patient population on 64-row MSCT CT coronary angiography (CTCA). Methods: One hundred patients (group A) underwent CTCA consecutively using standard protocol with a fixed mA. The mean CT value of a fixed ROI (region of interest) from the scout AP view and the CTCA image noise (standard deviation on the root of ascending aorta) were measured. The correlation between CT values and noise was studied to establish a formula and a list to determine the required mA for obtaining a consistent CTCA image noise based on the measured SV CT value. Another 100 patients (group B) were scanned using the same parameters as group A except the mA and the CT value was also measured. The mA was determined by the list established previously. The CTCA image quality (IQ) as well as the image noise (IN) and the effective dose (ED) from the two groups were statistically analyzed using t-test. The CT findings for the 32 patients in the group B were also compared with the selective coronary angiography (SCA) results. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CTCA for detection of significant stenosis were obtained. Results: The formula between the required mA and the CT value was: XmA=FmA x [(K 1 x CTscout + C 1 )/INa] 2 . The CTCA images in B group had statistically higher IN (27.66±2.57, 22.22±4.17, t=11.33, P=0.000), but no statistical difference between IQ scores for the two groups (3.29±0.66, 3.37±0.67, t=0.009, P=0.990), and ED [(8.72±2.51) versus (12.53±0.90) mSv] was 30% lower for the B group (P<0.01). For the 32 patients in the B group who had SCA, the CTCA sensitivity, specificity, positive predictive value, negative

Clinical usefulness of multidetector-row CT to evaluate coronary artery calcium score in type 2 diabetes

International Nuclear Information System (INIS)

Nishioka, Makiko; Sakuma, Toru; Sano, Hironari; Utsunomiya, Kazunori; Agata, Toshihiko; Shimizu, Keisuke; Tajima, Naoko

2004-01-01

According to recent studies, multidetector-row CT (MDCT) with a retrospective electrocardiogram (ECG)-gating reconstruction algorithm shows a high correlation with coronary artery calcium score determined using electron-beam CT. Diabetes leads to many macrovascular complications, including coronary artery disease. The aim of this study was to evaluate risk factors for cardiac macroangiopathy in type 2 diabetes using MDCT. An observational cross-sectional study was performed in 90 patients with diabetes mellitus. Coronary calcium data was acquired by MDCT (SOMATOM Volume Zoom, Siemens AG, Medical Solutions, Germany). Physical examinations, laboratory data, glycemic control, and control of other risk factors were analyzed. The coronary artery calcium score increased with age. Multivariant analysis revealed that the coronary calcium score was closely correlated with electrocardiogram evaluation and control of hypertension. Coronary artery calcium score as determined by MDCT can be used as a screening radiological examination for cardiac macroangiopathy in diabetes patients with electrocardiogram abnormality and hypertension. (author)

Diagnosis of preoperative staging of bladder cancer by CT and angiography

International Nuclear Information System (INIS)

Munechika, Hirotsugu; Saito, Kazuhiko; Tanaka, Osamu; Tomiie, Fumitaka; Aihara, Toshinori

1982-01-01

The accuracy of computed tomography (CT) and angiography in defining the extent of local invasion was studied retrospectively in 19 patients with surgically proven carcinoma of the bladder. The overall accuracy of CT and angiographic staging in these cases was 54 percent and 47 percent respectively. The diagnosis of carcinoma of the bladder by CT tended to do overstaging rather than understaging. A tangential view of the tumor-bearing area by the selective internal iliac arteriography allows an accurate estimation of the perivesical tumor extension. The topographic diagnosis should be made by CT prior to the angiographic study. (author)

Tuberculous Addison's disease: Morphological and quantitative evaluation with multidetector-row CT

International Nuclear Information System (INIS)

Ma Ensen; Yang Zhigang; Li Yuan; Guo Yingkun; Deng Yuping; Zhang Xiaochun

2007-01-01

Objective: To determine the characteristics of tuberculous Addison's disease on the axial and multiplanar reformatted (MPR) images of the multidetector-row computed tomography (MDCT). Materials and methods: The unenhanced and contrast-enhanced MDCT features in 19 patients with tuberculous Addison's disease were retrospectively assessed for the location, contour, size, calcification, attenuation, and enhancement patterns. The correlation between the duration of Addison's disease and the percentage of calcification presence was evaluated. Results: The adrenal glands were infected bilaterally in all of the 19 cases (100%, 38 glands). Enlargement of the glands appeared in 18 cases (94.7%, 36 glands) and the remaining one case (5.3%, two glands) showed atrophy bilaterally. Of the 36 enlarged adrenals, 13 (36.1%) had preserved contours, and the other 23 (63.9%) were mass-like. The size of the adrenals ranged from 0.6 to 4.8cm (mean 1.92+/-0.96cm). Calcification was revealed in 16 adrenals (16/38, 42.1%), increasing in incidence with disease progression. Fourteen of the 36 (38.9%) enlarged adrenals showed peripheral enhancement while the remaining 22 (61.1%) demonstrated heterogeneous enhancement. The ΔCT value, the attenuation measurement of mass-like lesions, was less in the central area (7+/-4HU) than that in the peripheral area (32+/-14HU) (P<0.01) between the unenhanced and contrast-enhanced scan. Conclusion: MDCT can reveal the characteristic morphology and CT attenuation in the tuberculous Addison's disease. Combined with its clinical presentations and biochemical findings, we can diagnose and stage adrenal tuberculosis with high specificity and accuracy on MDCT

Suitability of helical multislice acquisition technique for routine unenhanced brain CT: an image quality study using a 16-row detector configuration

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Hernalsteen, Danielle; Cosnard, Guy; Grandin, Cecile; Duprez, Thierry [Universite Catholique de Louvain, Cliniques Universitaires Saint-Luc, Department of Radiology and Medical Imaging, Brussels (Belgium); Robert, Annie [Public Health School, Universite Catholique de Louvain, Department of Epidemiologics and Medical Statistics, Brussels (Belgium); Vlassenbroek, Alain [CT Clinical Science, Philips Medical Systems, Cleveland, OH (United States)

2007-04-15

Subjective and objective image quality (IQ) criteria, radiation doses, and acquisition times were compared using incremental monoslice, incremental multislice, and helical multislice acquisition techniques for routine unenhanced brain computed tomography (CT). Twenty-four patients were examined by two techniques in the same imaging session using a 16-row CT system equipped with 0.75-width detectors. Contiguous ''native'' 3-mm-thick slices were reconstructed for all acquisitions from four detectors for each slice (4 x 0.75 mm), with one channel available per detector. Two protocols were tailored to compare: (1) one-slice vs four-slice incremental images; (2) incremental vs helical four-slice images. Two trained observers independently scored 12 subjective items of IQ. Preference for the technique was assessed by one-tailed t test and the interobserver variation by two-tailed t test. The two observers gave very close IQ scores for the three techniques without significant interobserver variations. Measured IQ parameters failed to reveal any difference between techniques, and an approximate half radiation dose reduction was obtained by using the full 16-row configuration. Acquisition times were cumulatively shortened by using the multislice and the helical modality. (orig.)

Suitability of helical multislice acquisition technique for routine unenhanced brain CT: an image quality study using a 16-row detector configuration

International Nuclear Information System (INIS)

Hernalsteen, Danielle; Cosnard, Guy; Grandin, Cecile; Duprez, Thierry; Robert, Annie; Vlassenbroek, Alain

2007-01-01

Subjective and objective image quality (IQ) criteria, radiation doses, and acquisition times were compared using incremental monoslice, incremental multislice, and helical multislice acquisition techniques for routine unenhanced brain computed tomography (CT). Twenty-four patients were examined by two techniques in the same imaging session using a 16-row CT system equipped with 0.75-width detectors. Contiguous ''native'' 3-mm-thick slices were reconstructed for all acquisitions from four detectors for each slice (4 x 0.75 mm), with one channel available per detector. Two protocols were tailored to compare: (1) one-slice vs four-slice incremental images; (2) incremental vs helical four-slice images. Two trained observers independently scored 12 subjective items of IQ. Preference for the technique was assessed by one-tailed t test and the interobserver variation by two-tailed t test. The two observers gave very close IQ scores for the three techniques without significant interobserver variations. Measured IQ parameters failed to reveal any difference between techniques, and an approximate half radiation dose reduction was obtained by using the full 16-row configuration. Acquisition times were cumulatively shortened by using the multislice and the helical modality. (orig.)

Effectiveness of thin-slice axial images of multidetector row CT for visualization of bronchial artery before bronchial arterial embolization

International Nuclear Information System (INIS)

Shida, Yoshitaka; Hasuo, Kanehiro; Aibe, Hitoshi; Kubo, Yuko; Terashima, Kotaro; Kinjo, Maya; Kamano, H.; Yoshida, Atsuko

2008-01-01

We assessed the ability of visualization of bronchial artery (BA) by using thin-slice axial images of 4-detector multidetector row CT in 65 patients with hemoptysis. In all patients, the origins of BA were well identified with observation of consecutive axial images with 1 mm thickness by paging method and bronchial arterial embolization (BAE) was performed successfully. Thin-slice axial images were considered to be useful to recognize BA and to perform BAE in patients with hemoptysis. (author)

Angiographic frequency of blunt cerebrovascular injury in patients with carotid canal or vertebral foramen fractures on multidetector CT

International Nuclear Information System (INIS)

McKinney, Alexander; Ott, Frederick; Short, James; McKinney, Zeke; Truwit, Charles

2007-01-01

Purpose: Blunt carotid injuries (BCI's) and blunt vertebral artery injuries (BVI's), known jointly as BCVI's, are common in 'high risk' patients. The purpose is to evaluate the rate of occurrence of BCI/BVI in patients screened purely by the radiologic criteria of fracture through the carotid canal or vertebral transverse foramina, or significant cervical subluxation, noted by multidetector CT. Methods: Seventy-one patients with 108 catheterized vessels were included over a 13-month interval. The angiographic examinations were prompted by current hospital protocol, solely by the presence of fractures involving/adjacent to the carotid canal, cervical fractures involving/adjacent to the foramen transversarium, or cervical fractures with significant subluxation. The incidence of each grade of blunt injury was calculated after review of the CT scans and catheter angiograms by two neuroradiologists. Results: Two thousand and seventy-three total blunt trauma admissions occurred during the time period, with a BCVI rate of 0.92-1.0% (depending on the reviewer), similar to previous studies. Mean time to catheter angiography was 16.6 h. Of the 71 included patients, there were 11-12 BCI's and 10-12 BVI's, an overall rate of 27-30% of BCVI in the patients with foraminal fractures. Interobserver agreement in reviewing the catheter angiograms was excellent (Kappa 0.795). Of note, three internal carotid pseudoaneurysms resolved spontaneously after anticoagulation or aspirin. Conclusion: This study confirms that there is a high rate of BCVI in the presence of carotid canal or vertebral foramen fractures that are noted by multidetector CT. Utilization of purely radiologic criteria of foraminal involvement may be a significant screening tool in the decision of whether to evaluate these patients acutely by catheter or CT angiography, and for early detection of patients at risk for symptomatology, to initiate prompt, prophylactic treatment

Angiographic frequency of blunt cerebrovascular injury in patients with carotid canal or vertebral foramen fractures on multidetector CT

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McKinney, Alexander [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States)]. E-mail: mckin022@umn.edu; Ott, Frederick [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States); Short, James [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States); McKinney, Zeke [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States); Truwit, Charles [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States)

2007-06-15

Purpose: Blunt carotid injuries (BCI's) and blunt vertebral artery injuries (BVI's), known jointly as BCVI's, are common in 'high risk' patients. The purpose is to evaluate the rate of occurrence of BCI/BVI in patients screened purely by the radiologic criteria of fracture through the carotid canal or vertebral transverse foramina, or significant cervical subluxation, noted by multidetector CT. Methods: Seventy-one patients with 108 catheterized vessels were included over a 13-month interval. The angiographic examinations were prompted by current hospital protocol, solely by the presence of fractures involving/adjacent to the carotid canal, cervical fractures involving/adjacent to the foramen transversarium, or cervical fractures with significant subluxation. The incidence of each grade of blunt injury was calculated after review of the CT scans and catheter angiograms by two neuroradiologists. Results: Two thousand and seventy-three total blunt trauma admissions occurred during the time period, with a BCVI rate of 0.92-1.0% (depending on the reviewer), similar to previous studies. Mean time to catheter angiography was 16.6 h. Of the 71 included patients, there were 11-12 BCI's and 10-12 BVI's, an overall rate of 27-30% of BCVI in the patients with foraminal fractures. Interobserver agreement in reviewing the catheter angiograms was excellent (Kappa 0.795). Of note, three internal carotid pseudoaneurysms resolved spontaneously after anticoagulation or aspirin. Conclusion: This study confirms that there is a high rate of BCVI in the presence of carotid canal or vertebral foramen fractures that are noted by multidetector CT. Utilization of purely radiologic criteria of foraminal involvement may be a significant screening tool in the decision of whether to evaluate these patients acutely by catheter or CT angiography, and for early detection of patients at risk for symptomatology, to initiate prompt, prophylactic treatment.

Detection and evaluation of intracranial aneurysms with 16-row multislice CT angiography

International Nuclear Information System (INIS)

Tipper, G.; U-King-Im, J.M.; Price, S.J.; Trivedi, R.A.; Cross, J.J.; Higgins, N.J.; Farmer, R.; Wat, J.; Kirollos, R.; Kirkpatrick, P.J.; Antoun, N.M.; Gillard, J.H.

2005-01-01

AIM: The aim of this study was to assess the usefulness of 16-row multislice CT angiography (CTA) in evaluating intracranial aneurysms, by comparison with conventional digital subtraction angiography (DSA) and intraoperative findings. METHODS: A consecutive series of 57 patients, scheduled for DSA for suspected intracranial aneurysm, was prospectively recruited to have CTA. This was performed with a 16-detector row machine, detector interval 0.75 mm, 0.5 rotation/s, table speed 10 mm/rotation and reconstruction interval 0.40 mm. CTA studies were independently and randomly assessed by two neuroradiologists and a vascular neurosurgeon blinded to the DSA and surgical findings. Review of CTA was performed on workstations with an interactive 3D volume-rendered algorithm. RESULTS: DSA or intraoperative findings or both confirmed 53 aneurysms in 44 patients. For both independent readers, sensitivity and specificity per aneurysm of DSA were 96.2% and 100%, respectively. Sensitivity and specificity of CTA were also 96.2% and 100%, respectively. Mean diameter of aneurysms was 6.3 mm (range 1.9 to 28.1 mm, SD 5.2 mm). For aneurysms of less than 3 mm, CTA had a sensitivity of 91.7% for each reader. Although the neurosurgeon would have been happy to proceed to surgery on the basis of CTA alone in all cases, he judged that DSA might have provided helpful additional anatomical information in 5 patients. CONCLUSION: The diagnostic accuracy of 16-slice CTA is promising and appears equivalent to that of DSA for detection and evaluation of intracranial aneurysms. A strategy of using CTA as the primary imaging method, with DSA reserved for cases of uncertainty, appears to be practical and safe

Three-dimensional reconstructions of the orbital floor by volume-rendering of multidetector-row CT data

International Nuclear Information System (INIS)

Yoshikawa, Tetsuya; Miyajima, Akira; Fujita, Yuko; Yamada, Kazuo

2011-01-01

The advent of 3D-CT has made the evaluation of complicated facial fractures much easier than before. However, its use in injuries involving the orbital floor has been limited by the difficulty of visualizing the thin bony structures given artifacts caused by the partial volume effect. Nevertheless, high-technology machines such as multidetector-row CT (MDCT) and new-generation software have improved the quality of 3D imaging, and this paper describes a procedure for obtaining better visualization of the orbital floor using a MDCT scanner. Forty trauma cases were subject to MDCT: 13 with injury to the orbital floor, and 27 without. All scans were performed in the standard manner, at slice thicknesses of 0.5 mm. 3D-CT images were created overlooking the orbital floor including soft tissue to minimize the pseudo-foramen artifacts produced through volume rendering. Bone deficits, fracture lines, and grafted bone were visible in the 3D images, and visualization was supported by the ready creation of stereoscopic images from MDCT volume data. Measurement of the pseudo-foramen revealed approximately half the artifacts to be less than 5 mm in diameter, suggesting practicality of this method without subjecting the patient to undue increases in radiation exposure in the treatment of cases involving injury to the orbital floor. (author)

Image quality of high-resolution CT with 16-channel multidetector-row CT. Comparison between helical scan and conventional step-shoot scan

International Nuclear Information System (INIS)

Sumikawa, Hiromitsu; Johkoh, Takeshi; Koyama, Mitsuhiro

2005-01-01

The aim of this study was to evaluate the image quality of high-resolution CT (HRCT) reconstructed from volumetric data with 16-channel multidetector-row CT (MDCT). Eleven autopsy lungs that were diagnosed histopathologically were scanned by 16-channel MDCT with the step-and-shoot scan mode and three helical scan modes. Each helical mode had each size of focal spot, pitch, and time of gantry rotation. HRCT images were reconstructed from the volumetric data with each helical mode and axial sequence data. Two observers evaluated the image quality and noted the most appropriate diagnosis for each imaging. Visualization of abnormal structures with one helical mode was equal to those with axial mode, whereas those with the other two helical modes were inferior to those with axial mode (Wilcoxon signed rank test; p<0.0001). There was no significant difference in diagnostic efficacy between modes. The image quality of HRCT with appropriate helical mode is equal to that with axial mode and diagnostic efficacy is equal among all modes. These results may indicate that sufficient HRCT images can be obtained by only one helical scan without the addition of conventional axial scans. (author)

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.

Using 80 kVp on a 320-row scanner for hepatic multiphasic CT reduces the contrast dose by 50 % in patients at risk for contrast-induced nephropathy

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Taguchi, Narumi; Oda, Seitaro; Utsunomiya, Daisuke; Nakaura, Takeshi; Imuta, Masanori; Yamamura, Sadahiro; Yuki, Hideaki; Kidoh, Masafumi; Hirata, Kenichiro; Namimoto, Tomohiro; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto (Japan); Funama, Yoshinori [Kumamoto University, Department of Medical Physics, Faculty of Life Sciences, Kumamoto (Japan); Hatemura, Masahiro; Kai, Noriyuki [Kumamoto University Hospital, Department of Central Radiology, Kumamoto (Japan)

2017-02-15

We evaluated the effects of a low contrast material (CM) dose protocol using 80-kVp on the image quality of hepatic multiphasic CT scans acquired on a 320-row CT scanner. We scanned 30 patients with renal insufficiency (eGFR < 45 mL/min/1.73 m{sup 2}) using 80-kVp and a CM dose of 300mgI/kg. Another 30 patients without renal insufficiency (eGFR > 60 mL/min/1.73 m{sup 2}) were scanned with the conventional 120-kVp protocol and the standard CM dose of 600mgI/kg. Quantitative image quality parameters, i.e. CT attenuation, image noise, and the contrast-to-noise ratio (CNR) were compared and the visual image quality was scored on a four-point scale. The volume CT dose index (CTDI{sub vol}) and the size-specific dose estimate (SSDE) recorded with the 80- and the 120-kVp protocols were also compared. Image noise and contrast enhancement were equivalent for the two protocols. There was no significant difference in the CNR of all anatomic sites and in the visual scores for overall image quality. The CTDI{sub vol} and SSDE were approximately 25-30 % lower under the 80-kVp protocol. Hepatic multiphase CT using 80-kVp on a 320-row CT scanner allowed for a decrease in the CM dose and a reduction in the radiation dose without image quality degradation in patients with renal insufficiency. (orig.)

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).

Evaluation of different 16-row CT colonography protocols using a porcine model; Evaluation unterschiedlicher 16-Zeilen-CT-Colonographie-Protokolle am Schweinedarmmodell

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Luz, O.; Schaefer, J.; Dammann, F.; Heuschmid, M.; Claussen, C.D. [Tuebingen Univ. (Germany). Abt. fuer Radiologische Diagnostik; Vonthein, R. [Universitaet Tuebingen (Germany). Institut fuer Biometrie

2004-10-01

Purpose: To develop and to test an easily produced biological colon model with simulated polypoid lesions. Application of this phantom for the selection of an optimized scan protocol of 16-row CT colonography (CTC) for clinical use. Methods and Material: Six polypoid lesions (1-6 mm) were simulated with sutures on the inner face of a porcine colon segment (20 cm). After distending the colon segment with air, the phantom was placed in a water quench and CT scans were performed on a MDCT-scanner (Somatom Sensation 16, Siemens, Forchheim). At constant values for collimation (16 x 0.75 mm) and voltage (120 kV), 54 different combinations of mAs values (50, 75 and 100 mAs), pitch factors (1, 1.25 and 1.5) and slice thicknesses (0.75, 1.0, 1.5, 2.0, 3.0 and 5.0 mm) were tested systematically. The phantom was scanned in the longitudinal and transverse axis to simulate the different orientation of the colon in the abdomen. Axial slice images and virtual endoscopic views of all data sets were presented separately to 2 radiologists who independently determined number and size of detectable polyps. Dose exposure was measured with an Alderson phantom. Results: The colon model offered a realistic imitation of a polyp-covered, human colon. The experimental set-up allowed a systematic evaluation of polyp detection related to lesion size, orientation of the colon and CTC parameters, with other influencing factors mostly excluded. Polyps were significantly better detected in the longitudinal than in the transverse orientation of the colon. For the detection of lesions of at least 3 mm, a low dose (50 mAs) 16-row CTC should be combined with a pitch of 1.5 and a maximum slice thickness of 3 mm. For the depiction of polyps smaller than 3 mm, slice thickness and pitch should amount to 1 mm and 1.0, respectively. Effective dose of this low dose protocol is 4.08 mSv. (orig.)

Renal artery origins: best angiographic projection angles.

Science.gov (United States)

Verschuyl, E J; Kaatee, R; Beek, F J; Patel, N H; Fontaine, A B; Daly, C P; Coldwell, D M; Bush, W H; Mali, W P

1997-10-01

To determine the best projection angles for imaging the renal artery origins in profile. A mathematical model of the anatomy at the renal artery origins in the transverse plane was used to analyze the amount of aortic lumen that projects over the renal artery origins at various projection angles. Computed tomographic (CT) angiographic data about the location of 400 renal artery origins in 200 patients were statistically analyzed. In patients with an abdominal aortic diameter no larger than 3.0 cm, approximately 0.5 mm of the proximal part of the renal artery and origin may be hidden from view if there is a projection error of +/-10 degrees from the ideal image. A combination of anteroposterior and 20 degrees and 40 degrees left anterior oblique projections resulted in a 92% yield of images that adequately profiled the renal artery origins. Right anterior oblique projections resulted in the least useful images. An error in projection angle of +/-10 degrees is acceptable for angiographic imaging of the renal artery origins. Patients sex, site of interest (left or right artery), and local diameter of the abdominal aorta are important factors to consider.

Angiographic CT: in vitro comparison of different carotid artery stents-does stent orientation matter?

Science.gov (United States)

Lettau, Michael; Bendszus, Martin; Hähnel, Stefan

2013-06-01

Our aim was to evaluate the in vitro visualization of different carotid artery stents on angiographic CT (ACT). Of particular interest was the influence of stent orientation to the angiography system by measurement of artificial lumen narrowing (ALN) caused by the stent material within the stented vessel segment to determine whether ACT can be used to detect restenosis within the stent. ACT appearances of 17 carotid artery stents of different designs and sizes (4.0 to 11.0 mm) were investigated in vitro. Stents were placed in different orientations to the angiography system. Standard algorithm image reconstruction and stent-optimized algorithm image reconstruction was performed. For each stent, ALN was calculated. With standard algorithm image reconstruction, ALN ranged from 19.0 to 43.6 %. With stent-optimized algorithm image reconstruction, ALN was significantly lower and ranged from 8.2 to 18.7 %. Stent struts could be visualized in all stents. Differences in ALN between the different stent orientations to the angiography system were not significant. ACT evaluation of vessel patency after stent placement is possible but is impaired by ALN. Stent orientation of the stents to the angiography system did not significantly influence ALN. Stent-optimized algorithm image reconstruction decreases ALN but further research is required to define the visibility of in-stent stenosis depending on image reconstruction.

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)

Clinical assessment of hypopharyngeal and laryngeal disorders by three-dimensional multidetector-row CT. Feasibility of imaging during phonation

International Nuclear Information System (INIS)

Tan, Xiaotian

2002-01-01

The hypopharynx and larynx can adapt their structures to physiological functions. To clarify the relation between morphologic changes and the development of pharyngeal and laryngeal disorders, images of the hypopharynx and larynx were obtained by multidetector-row CT (MD-CT) during phonation and quiet breathing. The clinical usefulness of such imaging study was assessed by comparing the images taken in the two phases. The study included 23 subjects, 20 patients with a hypopharyngeal or laryngeal disorder and 3 healthy volunteers. MD-CT scanning of the hypopharynx and larynx was not influenced by breathing and body movement. The volume rendering (VR) method was useful in that three-dimensional imaging could visualize the internal structure of the hypopharynx and larynx. Thus, the volume rendering method can be regarded as a virtual three-dimensional method. The normal anatomic structure of the hypopharynx and larynx were depicted in full and three-dimensionally. The extent of hypopharyngeal and laryngeal cancer was shown clearly. Edema due to paralysis of recurrent nerve was demonstrated in full and three-dimensionally, providing for functional diagnosis. In the case of mucosal edema caused by trauma, the extent of the edema and its effect on the airway were clearly observed. These results suggest that MD-CT with three-dimensional imaging during phonation is useful in the diagnosis of hypopharyngeal and laryngeal disorders. (author)

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

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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.

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.

Economic evaluation of angiographic interventions including a whole-radiology in- and outpatient care

International Nuclear Information System (INIS)

Nolte-Ernsting, C.; Abel, K.; Krupski, G.; Lorenzen, J.; Adam, G.

2006-01-01

Purpose: To determine the economic efficiency of a whole-radiology in- and outpatient treatment with angiographic interventions performed as the main or sole therapy. Materials and Methods: The calculations represent the data of a university radiology department, including the following angiographic interventions (neuroradiology not considered): Vascular intervention (PTA, stent implantation) of kidneys and extremities, recanalization of hemodialysis access, chemoembolization, diagnostic arterioportal liver CT, port implantation, varicocele embolization, PTCD, percutaneous implantation of biliary stent. First, the different angiographic interventions are categorized with reference to the German DRG system 2005. Considering the example of a university hospital, the individual cost of each intervention is calculated and correlated with reimbursements by G-DRG2005 and so-called ''ambulant operation'' (EBM200plus). With these data, profits and losses are calculated for both in- and outpatient care. Results: Radiologic interventions of inpatients yield a profit in the majority of cases. With a base rate of 2900 Euro, the profits in our university hospital range between -872 Euro and +3411 Euro (mean: +1348 Euro). On the other hand, those angiographic interventions suitable for ''ambulant operation'' generate average profits of +372 Euro, if only direct costs are considered. The data of outpatient radiological interventions average between 381 Euro up to 1612 Euro lower than compared with profits obtained from in patient care. (orig.)

Pediatric renovascular hypertension in Thailand: CT angiographic findings

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Visrutaratna, Pannee; Srisuwan, Tanop; Sirivanichai, Chusak [Chiang Mai University, Department of Radiology, Faculty of Medicine, Chiang Mai (Thailand)

2009-12-15

Renovascular disease is an uncommon but important cause of hypertension in children. When unrecognized and untreated, renovascular hypertension in children can have serious complications. To review the causes of renovascular hypertension and computed tomography angiographic (CTA) findings in children and adolescents. Twenty-eight CTAs from January 2004 to March 2008 of 23 children and adolescents with hypertension were reviewed for the causes and CTA findings. Nine of the 23 children (39%) had abnormal renal arteries with or without abnormal abdominal aortas. Four of these children had Takayasu arteritis, one had moyamoya disease, and one had median arcuate ligament syndrome. One with chronic pyelonephritis had severe stenosis of the proximal right renal artery. The other two children had renal artery stenosis with a nonspecific cause. One child with a normal abdominal aorta and renal arteries had a right suprarenal mass. On pathological examination a ganglioneuroma was found. CTA can help in diagnosis of renovascular hypertension in children and adolescents. Although CTA is not a screening modality, it is appropriate in some situations. (orig.)

Pediatric renovascular hypertension in Thailand: CT angiographic findings

International Nuclear Information System (INIS)

Visrutaratna, Pannee; Srisuwan, Tanop; Sirivanichai, Chusak

2009-01-01

Renovascular disease is an uncommon but important cause of hypertension in children. When unrecognized and untreated, renovascular hypertension in children can have serious complications. To review the causes of renovascular hypertension and computed tomography angiographic (CTA) findings in children and adolescents. Twenty-eight CTAs from January 2004 to March 2008 of 23 children and adolescents with hypertension were reviewed for the causes and CTA findings. Nine of the 23 children (39%) had abnormal renal arteries with or without abnormal abdominal aortas. Four of these children had Takayasu arteritis, one had moyamoya disease, and one had median arcuate ligament syndrome. One with chronic pyelonephritis had severe stenosis of the proximal right renal artery. The other two children had renal artery stenosis with a nonspecific cause. One child with a normal abdominal aorta and renal arteries had a right suprarenal mass. On pathological examination a ganglioneuroma was found. CTA can help in diagnosis of renovascular hypertension in children and adolescents. Although CTA is not a screening modality, it is appropriate in some situations. (orig.)

Upper abdominal gadoxetic acid-enhanced and diffusion-weighted MRI for the detection of gastric cancer: Comparison with two-dimensional multidetector row CT

International Nuclear Information System (INIS)

Jang, K.M.; Kim, S.H.; Lee, S.J.; Lee, M.W.; Choi, D.; Kim, K.M.

2014-01-01

Aim: To evaluate the diagnostic performance of abdominal magnetic resonance imaging (MRI) for the detection of gastric cancer in comparison with that of two-dimensional (2D) multidetector row computed tomography (CT). Materials and methods: The study included 189 patients with 170 surgically confirmed gastric cancers and 19 patients without gastric cancer, all of whom underwent gadoxetic acid-enhanced MRI with diffusion-weighted (DW) imaging, and multidetector contrast-enhanced abdominal CT imaging. Two observers independently analysed three sets of images (CT set, conventional MRI set, and combined conventional and DW MRI set). A five-point scale for likelihood of gastric cancer was used. Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were evaluated. Quantitative [apparent diffusion coefficient (ADC) analyses with Mann–Whitney U-test were conducted for gastric cancers and the nearby normal gastric wall. Results: The diagnostic accuracy and sensitivity for detection of gastric cancer were significantly higher on combined conventional and DW MRI set (77.8–78.3%; 75.3–75.9%) than the CT imaging set (67.7–71.4%; 64.1–68.2%) or the conventional MRI set (72–73%; 68.8–70%; p < 0.01). In particular, for gastric cancers with pT2 and pT3, the combined conventional and DW MRI set (91.6–92.6%) yielded significantly higher sensitivity for detection of gastric cancer than did the CT imaging set (76.8–81.1%) by both observers (p < 0.01). The mean ADC of gastric cancer lesions (1 ± 0.23 × 10 −3 mm 2 /s) differed significantly from that of normal gastric wall (1.77 ± 0.25 × 10 −3  mm 2 /s; p < 0.01). Conclusion: Abdominal MRI with DW imaging was more sensitive for the detection of gastric cancer than 2D-multidetector row CT or conventional MRI alone. - Highlights: • The sensitivity for detection of gastric cancer is high on abdominal MR imaging. • DW imaging is helpful for

Angiographic features of 26 children with Takayasu's arteritis

International Nuclear Information System (INIS)

McCulloch, M.; Goddard, E.; Sinclair, P.; Andronikou, S.; Mandelstam, S.; Beningfield, S.J.; Lawrenson, J.; Millar, A.J.W.

2003-01-01

Background: Takayasu's arteritis (TA) is a chronic idiopathic inflammatory disease affecting primarily the aorta, its proximal branches and the pulmonary arteries Objectives: To retrospectively review the angiograms of children with TA so as to describe the patterns of vascular involvement. Patients and methods: Twenty-six children with TA who differed from most other studies in that almost all of them presented with hypertension, reflecting the incidence of abdominal aortic and renal artery involvement. Results: The most consistent finding was stenosis of the aorta. Marginal irregularity/undulation of the aorta was also a useful angiographic diagnostic feature in subtle disease. The incidence of aneurysms was high compared to other studies and both fusiform and saccular aneurysms were encountered. Percutaneous transluminal angioplasty (PTA) was successful in all eight patients in whom it was performed. MRI, CT angiography and US are discussed as less invasive imaging alternatives. TA is a significant cause of renovascular hypertension in children in South Africa where there is a high incidence of tuberculous infection. Knowledge of the angiographic features and pattern of aortic involvement is essential for diagnosis and initiation of early and appropriate treatment, including PTA. (orig.)

Prevalence and configuration of pulmonary nodules on multi-row CT in children without malignant diseases

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Renne, Julius; Wacker, Frank; Berthold, Lars-Daniel; Weidemann, Juergen [Hannover Medical School, Institute for Diagnostic and Interventional Radiology, Hannover (Germany); Linderkamp, Christin [Hannover Medical School, Pediatric Oncology, Hannover (Germany)

2015-09-15

To assess the prevalence and morphologic characterization of pulmonary nodules in children on a chest computed tomography (CT). Two hundred and fifty-nine trauma chest CTs in children aged 0-18 years were retrospectively reviewed by two radiologists, each with more than 10 years of experience. Images were acquired on a 64-row CT. Pulmonary lobes with trauma affections such as contusion or haemorrhage were excluded. All pulmonary nodules were evaluated for distance from the pleural surface, location, calcification and size on axial slices. A total of 1,190/1,295 (92 %) pulmonary lobes without traumatic injury were included in this study. In 86 of 259 (33 %) patients, 131 pulmonary nodules were detected. Number of nodules per patient ranged from 1 to 4. Calcifications were seen in 19 % (25) of all nodules. Diameters ranged from 1 to 5 mm. 59 % (77) were located in the lower lobes, 9 % (12) in the middle lobe and 32 % (42) in the upper lobes. 84 % of the non-calcified nodules >2 mm showed a slightly angular or triangular (mostly pleural nodes) shape. Pulmonary nodules smaller than 5 mm can be detected frequently in children without malignant disease and are predominantly located in the lower lobes. (orig.)

Radiological emergency room management with emphasis on multidetector-row

Energy Technology Data Exchange (ETDEWEB)

Philipp, M.O.; Kubin, K.; Hoermann, M.; Metz, V.M. E-mail: viktor.metz@univie.ac.at

2003-10-01

Trauma is the fifth leading cause of death after disease of the cardiovascular system, malignomas and disease of the respiratory and digestive system. The management of severely injured patients, including radiological imaging, is a matter of ongoing development. In particular, as for the imaging modalities, multidetector-row CT represents a substantial refinement in the diagnostic work-up of multitrauma patients. Sufficient therapy within the first hour after trauma increases the patient's chances for survival significantly. Thus, therapeutic procedures and diagnostic evaluation have to be concomitant events, performed by a multidisciplinary team, namely trauma surgeon, anesthesiologist and, last but not least, radiologist. The increased performance of multidetector-row CT leads to increased spatial resolution, which is a prerequisite for sophisticated two- and three-dimensional postprocessing. The increased volume coverage speed allows for comprehensive whole-body CT at still high levels of spatial resolution, resulting in significant spare of time which influences patient's survival. Using this technique conventional imaging such as plane film or angiography may be omitted.

Chronic intestinal pseudo-obstruction in adult patients: multidetector row helical CT features

International Nuclear Information System (INIS)

Merlin, Aurelie; Soyer, Philippe; Boudiaf, Mourad; Hamzi, Lounis; Rymer, Roland

2008-01-01

Chronic intestinal pseudo-obstruction (CIPO) is a rare condition due to severe gastrointestinal motility disorder. Adult patients with CIPO experience symptoms of mechanical obstruction, but reliable clinical signs that may help distinguish between actual mechanical obstruction and CIPO are lacking. Additionally, abdominal plain films that commonly show bowel dilatation with air-fluid levels do not reach acceptable degrees of specificity to exclude actual obstruction. Therefore, most adult patients with CIPO usually undergo multiple and often fruitless surgery, often leading to repeated bowel resections before diagnosis is made. In these patients who present with abdominal signs mimicking symptoms that would warrant surgical exploration, multidetector-row helical CT (MDCT) is helpful to resolve this diagnostic dilemma. MDCT shows a diffusely distended bowel and helps to rule out a mechanical cause of obstruction, thus suggesting CIPO and obviating the need for unnecessary laparotomy. In adult patients with CIPO, MDCT may show pneumatosis intestinalis, pneumoperitoneum or intussusception. However, these conditions generally do not require surgery in patients with CIPO. This pictorial essay presents the more and less common MDCT features of CIPO in adult patients, to make the reader more familiar with this disease. (orig.)

Extended use of cranial CT in the evaluation of patients with stroke and transient ischaemic attacks

International Nuclear Information System (INIS)

Stevens, J.M.; Barber, C.J.; Kerslake, R.; Broz, M.; Barter, S.

1991-01-01

The hypothesis was explored that patterns of ischaemic brain damage shown by CT may be of greater value in estimating the relevance of angiographic stenosis in the carotico-vertebral arteries in some patients than presenting clinical features. Five angiographic and six CT abnormalities were defined and charted independently in a blinded manner in 312 patients in whom clinical features and subsequent management were known. Charts were combined for statistical analysis. Statistically significant associations were found between two types of CT lesion and angiographic abnormalities, but these were present in only 18% of cases. The distribution of clinical features did not differ significantly within this subset compared to the whole population, from which it was concluded that the hypothesis was upheld. Furthermore significantly more patients in this subset were subjected to carotid endarterectomy, suggesting that management decisions may have been modulated by CT findings in some patients. (orig.)

Percutaneous vertebroplasty with a high-quality rotational angiographic unit

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Pedicelli, Alessandro [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: apedicelli@rm.unicatt.it; Rollo, Massimo [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: mrollo@rm.unicatt.it; Piano, Mariangela [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: mariangela.piano@gmail.com; Re, Thomas J. [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: tomjre@gmail.com; Cipriani, Maria C. [Department of Gerontology, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: alexped@yahoo.com; Colosimo, Cesare [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: colosimo@rm.unicatt.it; Bonomo, Lorenzo [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: lbonomo@rm.unicatt.it

2009-02-15

We evaluated the reliability of a rotational angiographic unit (RA) with flat-panel detector as a single technique to guide percutaneous vertebroplasty (PVP) and for post-procedure assessment by 2D and 3D reformatted images. Fifty-five consecutive patients (104 vertebral bodies) were treated under RA fluoroscopy. Rotational acquisitions with 2D and 3D reconstruction were obtained in all patients for immediate post-procedure assessment. In complex cases, this technique was also used to evaluate the needle position during the procedure. All patients underwent CT scan after the procedure. RA and CT findings were compared. In all cases, a safe trans-pedicular access and an accurate control of the bone-cement injection were successfully performed with high-quality fluoroscopy, even at the thoracic levels and in case of vertebra plana. 2D and 3D rotational reconstructions permitted CT-like images that clearly showed needle position and were similar to CT findings in depicting intrasomatic implant-distribution. RA detected 40 cement leakages compared to 42 demonstrated by CT and showed overall 95% sensitivity and 100% specificity compared to CT for final post-procedure assessment. Our preliminary results suggest that high-quality RA is reliable and safe as a single technique for PVP guidance, control and post-procedure assessment. It permits fast and cost-effective procedures avoiding multi-modality imaging.

Evaluation of angiographic delayed vasospasm due to ruptured aneurysm in comparison with cerebral circulation time measured by IA-DSA

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Okada, Yoshikazu; Shima, Takeshi; Nishida, Masahiro; Yamane, Kanji; Okita, Shinji; Hatayama, Takashi; Yoshida, Akira; Naoe, Yasutaka; Shiga, Naoko (Chugoku Rosai Hospital, Hiroshima (Japan))

1994-05-01

Delayed vasospasm due to ruptured aneurysm has been basically evaluated by angiographic changes in contrast to clinical features such as delayed ischemic neurological deficits (DIND). However, the discrepancies between angiographic and clinical findings have been pointed out. In this study, angiographic changes and cerebral circulation time in ruptured aneurysms were simultaneously investigated with IA-DSA. Thirty-two patients, who had ruptured aneurysms at the anterior circle of Willis and neck clippings at the acute stage, were investigated. Carotid angiogram was performed with IA-DSA on the 7-13th day after the attack. Angiographic changes were evaluated by Fischer's classification and circulation time was calculated in the following way. A time-density curve was obtained at the two ROI's: the C3-C4 portion and the rolandic vein. Circulation time was defined by the difference between the time showing peak optical density at the carotid and the venous portion. The control value of this circulation time obtained from 20 cases with non-rupture aneurysm and epilepsy was 3.4 sec (53 year old) on the average. X-ray CT scan examination was performed at the same time and clinical features were observed every day. Angiographically, 3 cases were free from vasospasm, 18 cases were found to present slight to moderate vasospasm, and 11 cases showed severe vasospasm. Circulation time in patients with no spasm was 3.6 seconds, in patients with slight to moderate vasospasm it was 4.3 seconds and in patients with severe vasospasm it was 6.8 seconds. Ten patients showing cerebral infarction on CT scans demonstrated significantly long circulation time, 7.0 seconds on the average. And all patients having severe vasospasm with circulation time more than 6 seconds presented DIND such as hemiparesis. (author).

Evaluation of Deep Vein Thrombosis with Multidetector Row CT after Orthopedic Arthroplasty: a Prospective Study for Comparison with Doppler Sonography

International Nuclear Information System (INIS)

Byun, Sung Su; Kim, Youn Jeong; Chun, Yong Sun; Kim, Won Hong; Kim, Jeong Ho; Park, Chul Hi

2008-01-01

This prospective study evaluated the ability of indirect 16-row multidetector CT venography, in comparison with Doppler sonography, to detect deep vein thrombosis after total hip or knee replacement. Sixty-two patients had undergone orthopedic replacement surgery on a total of 30 hip joints and 54 knee joints. The CT venography (scan delay time: 180 seconds; slice thickness/increment: 2/1.5 mm) and Doppler sonography were performed 8 to 40 days after surgery. We measured the z-axis length of the beam hardening artifact that degraded the image quality so that the presence of deep vein thrombosis couldn't be evaluated on the axial CT images. The incidence and location of deep vein thrombosis was analyzed. The diagnostic performance of the CT venograms was evaluated and compared with that of Doppler sonography as a standard of reference. The z-axis length (mean±standard deviation) of the beam hardening artifact was 4.5±0.8 cm in the arthroplastic knees and 3.9±2.9 cm in the arthroplastic hips. Deep vein thrombosis (DVT) was found in the popliteal or calf veins on Doppler sonography in 30 (48%) of the 62 patients. The CT venography has a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 90%, 97%, 96%, 91% and 94%, respectively. The ability of CT venography to detect DVT was comparable to that of Doppler sonography despite of beam hardening artifact. Therefore, CT venography is feasible to use as an alternative modality for evaluating postarthroplasty patients

Evaluation of Deep Vein Thrombosis with Multidetector Row CT after Orthopedic Arthroplasty: a Prospective Study for Comparison with Doppler Sonography

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Byun, Sung Su; Kim, Youn Jeong; Chun, Yong Sun; Kim, Won Hong [Inha University, College of Medicine, Incheon (Korea, Republic of); Kim, Jeong Ho; Park, Chul Hi [Gachon University, Gil Medical Center, Incheon (Korea, Republic of)

2008-02-15

This prospective study evaluated the ability of indirect 16-row multidetector CT venography, in comparison with Doppler sonography, to detect deep vein thrombosis after total hip or knee replacement. Sixty-two patients had undergone orthopedic replacement surgery on a total of 30 hip joints and 54 knee joints. The CT venography (scan delay time: 180 seconds; slice thickness/increment: 2/1.5 mm) and Doppler sonography were performed 8 to 40 days after surgery. We measured the z-axis length of the beam hardening artifact that degraded the image quality so that the presence of deep vein thrombosis couldn't be evaluated on the axial CT images. The incidence and location of deep vein thrombosis was analyzed. The diagnostic performance of the CT venograms was evaluated and compared with that of Doppler sonography as a standard of reference. The z-axis length (mean{+-}standard deviation) of the beam hardening artifact was 4.5{+-}0.8 cm in the arthroplastic knees and 3.9{+-}2.9 cm in the arthroplastic hips. Deep vein thrombosis (DVT) was found in the popliteal or calf veins on Doppler sonography in 30 (48%) of the 62 patients. The CT venography has a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 90%, 97%, 96%, 91% and 94%, respectively. The ability of CT venography to detect DVT was comparable to that of Doppler sonography despite of beam hardening artifact. Therefore, CT venography is feasible to use as an alternative modality for evaluating postarthroplasty patients.

[CT measurement and clinical application of double-row suture anchor reconstruction for the treatment of Tossy type III acromioclavicular joint dislocation].

Science.gov (United States)

Zhang, Chuan-Kai; Liu, Chen; Han, Bing; Feng, Hui; Chen, Qi-Zhong; Sunx, Sun Yi-Yan

2017-04-25

To study feasibility and reliability of reconstruction of the acromioclavicular ligament with double-row suture anchor for the treatment of acromioclavicular joint dislocation through coracoid coronal CT measurement, and to provide a new operation method for treating acromioclavicular joint dislocation. Total 60 healthy people received CT examination of shoulder joint, including 30 males and 30 females, ranging in age from 18 to 50 years old. The coronal width, thickness and 20 degree camber angle in the medial part of the toot of coronal were measured using CT scan. The results were applied to clinical treatment for 12 patients with acromioclavicular joint dislocation of Tossy III type. The width in the medial part of the root of the coracoid was(17.65±1.82) mm(left side) and (17.67±1.80) mm(right side) in males; (16.55±1.78) mm(left side) and (16.52±1.74) mm (right side) in females. The vertical thickness of the roots of the coracoid: (13.11±2.11) mm(left side) and (13.16±2.09) mm(right side) in males;(12.79±2.21) mm(left side) and (12.76±2.19) mm (right side) in females. The thickness of 20 degrees camber angle of the coracoid roots: (16.32±1.74) mm (left side) and (16.30±1.69) mm(right side) in males; (15.68±1.44) mm(left side) and (15.67±1.43) mm(right side) in females. Total 12 patients were treated with anchor nail with extraversion 20 degrees. The postoperative X-ray films showed bone anchors were located in the coracoid process, no bone splitting. Double-row suture anchor of 5 mm diameter nails can be placed into coracoid with extraversion 20 degrees, which is safety.

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 ...

Adrenal pseudomasses due to varices: angiographic-CT-MRI-pathologic correlations

International Nuclear Information System (INIS)

Brady, T.M.; Gross, B.H.; Glazer, G.M.; Williams, D.M.

1985-01-01

Periadrenal and adrenal portosystemic collaterals are a recently reported cause of adrenal pseudotumor on computed tomography (CT). Nine patients with this left adrenal pseudotumor illustrate its typical position and appearance on CT, angiography, CT-angiography, and magnetic resonance imaging (MRI). The anatomic basis for variceal adrenal pseudotumors is the left inferior phrenic vein, which passes immediately anterior to the left adrenal gland and which serves as a collateral pathway from splenic to left renal vein in portal hypertension. Thus, unlike previously described adrenal pseudotumors, these venous collaterals are not anatomically distinguishable from the adrenal gland on CT. Bolus dynamic CT is usually diagnostic, but in equivocal cases, MRI may prove useful

Adrenal pseudomasses due to varices: angiographic-CT-MRI-pathologic correlations

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Brady, T.M.; Gross, B.H.; Glazer, G.M. Williams, D.M.

1985-08-01

Periadrenal and adrenal portosystemic collaterals are a recently reported cause of adrenal pseudotumor on computed tomography (CT). Nine patients with this left adrenal pseudotumor illustrate its typical position and appearance on CT, angiography, CT-angiography, and magnetic resonance imaging (MRI). The anatomic basis for variceal adrenal pseudotumors is the left inferior phrenic vein, which passes immediately anterior to the left adrenal gland and which serves as a collateral pathway from splenic to left renal vein in portal hypertension. Thus, unlike previously described adrenal pseudotumors, these venous collaterals are not anatomically distinguishable from the adrenal gland on CT. Bolus dynamic CT is usually diagnostic, but in equivocal cases, MRI may prove useful.

A study of low-density areas, clinical findings, and angiographic findings in patients with cerebral infarction

International Nuclear Information System (INIS)

Saiki, Iwao; Sakai, Yoshiaki; Oikawa, Tadato; Koide, Kohji; Kanaya, Haruyuki.

1978-01-01

55 out of 62 patients with cerebral infarction were investigated in terms of CT scan findings, angiographic findings, and clinical symptoms. The results obtained were as follows: 1) The low-density areas of the CT scan findings were classified into the following four types: large hemispheric or lobular --Type I; wedge-shaped --Type II; small --Type III; and lacunar low-density area. --Type IV. 2) Almost all patients with angiographically occlusive findings showed low-density areas of Type I; however, one patient with ICA occlusion revealed only a lacunar low-density area. 3) The patients with lacunar low-density areas showed an angiographically delayed filling of the angular artery and posterior parietal artery of the middle cerebral artery. 4) The relationship between the types of low-density areas and the clinical conscious disorders was not clear. On the other hand, the patients with Type I low-density areas almost all had motor disturbances, while patients with other types of low-density areas showed only 60 - 70% motor disturbances. 5) In patients with speech disorders, total aphasia cases were found in patients with large hemispheric low-density areas on the left side. Although, motor aphasia cases were seen in patients with various low-density areas on the left inferior frontal and precentral gyri, dysarthria cases were found in the patients with several low-density areas on both sides. 6) The localization of lacunar low-density areas seemed to be near the caudate nucleus on the right side and in the putaminal regions on the left side. The mean and the standard deviation of CT numbers in the lacunar low-density areas showed higher values on the right side than on the left side. (author)

Pitfalls in multidetector row CT colonography

International Nuclear Information System (INIS)

Stoyneva, V.

2009-01-01

Full text:MDCT colonography is a reliable method for detection and identification of type of the colon lesions. At every step of the examination an error could be made and that would be lead to an incorrect diagnosis. Problems and pitfalls can be overcome with various useful techniques. The relatively clean and dry colon after careful preparation, allows avoiding problems of residual fluid and faeces. The knowledge about the structure and thickness characteristics of lesions of the colon and artefacts can to be useful in distinction of the polypoidal lesions from normal findings. The aim of this lecture is to describe common and less common pitfalls in CT colonography and to clarify features and CT criteria to distinction of organic formations from pseudo lesions. Inadequate preparation of the patient, weaknesses into the protocol, gaps and errors in interpretation are responsible for false positive and false negative results. The training which reduces the residual solids and liquid, marking, protocols elaboration and CAD allows achieving higher sensitivity and specificity. The 2D and 3D application techniques and solid knowledge about CT characteristic of the colon organic findings and pseudo lesions will reduce the rate of false positive results

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)

Surgical Management of Juvenile Nasopharyngeal Angiofibroma Without Angiographic Embolization

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Raja Ahmad

2008-10-01

Full Text Available Juvenile nasopharyngeal angiofibroma (JNA is a rare benign neoplasm that occurs almost exclusively in the nasopharynx of adolescent males. Surgery remains the primary treatment of choice. JNA has always presented a management challenge to surgeons because of its vascular nature, site of occurrence, and local tissue destruction. The surgical approaches are either standard open method which include external or intraoral incisions, or the recent advanced approach, i.e. via using the endonasal endoscope. It is widely accepted that the use of preoperative angiographic embolization reduces the occurrence of intraoperative bleeding and facilitates tumour removal. However, angiographic embolization is not available at all centres. The purpose of this article is to present our experience with five patients diagnosed with JNA who were resected without embolization, using various surgical approaches. Two tumours were removed via endonasal endoscopic surgery. None of the tumours were embolized prior to surgery. We highlight the preoperative evaluation of tumour extent, using both computed tomography (CT and magnetic resonance angiography, and the importance of temporary clamping of the external carotid artery intraoperatively. Our results suggest that the latter procedure is a safe and effective means of facilitating surgery and reducing intraoperative bleeding.

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)

Coronary CT in Acute Cardiac Care

NARCIS (Netherlands)

A. Dedic (Admir)

2016-01-01

markdownabstractCoronary CT angiography is a well-established diagnostic modality for stable angina pectoris. It provides an angiographic, non-invasive alternative for the diagnosis of coronary artery disease, exceeding in the ability to exclude important coronary artery disease. Having the ability

Assessment of coronary arteries in infants by 64-detector-row multislice spiral computed tomography

International Nuclear Information System (INIS)

Tahara, Masahiro; Waki, Chiaki; Komatsu, Hiroaki; Hayashi, Tomohiro; Sato, Tomoyasu

2008-01-01

Heart rate is one of the most important factors for optimal visualization of cardiac CT. We investigated the relation between heart rate and visibility of the coronary arteries with 64-detector row multislice spiral computed tomography (MSCT). Three simulated coronary artery stenosis models (3, 4, and 5 mm) were attached to a moving heart phantom and scanned using 64-detector row MSCT. The heart rate of the phantom was varied between 60 and 150 beats per minutes (bpm). The visibility of simulated coronary arteries was assessed in comparison between cardiac half reconstruction (CHR) and multi-sector reconstruction (MSR). Then contrast-enhanced 64-detector row MSCT was performed in 16 patients under 3 years of age with congenital heart disease and Kawasaki disease without heart rate control. The visibility of coronary artery segments was graded on a three-point scale. The simulated coronary artery patency was detected in the moving phantom at maximum heart rate (150 bpm) with MSR. Minimum lumen diameter was 0.75 mm. Electrocardiogram (ECG)-gated cardiac CT was performed in 9 patients, and non-ECG-gated cardiac CT was performed in 7 patients. The origin and proximal course of coronary arteries in all 9 patients with ECG-gated acquisition were visually evaluated. 64-detector row MSCT with ECG-gated acquisition is able to visualize the origin and proximal course of coronary arteries in infants under 3 years of age. (author)

CT findings of diffuse malignant leptomeningeal melanoma

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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.

Radiologist and angiographic procedures. Absorbed radiation dose

International Nuclear Information System (INIS)

Tryhus, M.; Mettler, F.A. Jr.; Kelsey, C.

1987-01-01

The radiation dose absorbed by the angiographer during angiographic procedures is of vital importance to the radiologist. Nevertheless, most articles on the subject are incomplete, and few measure gonadal dose. In this study, three TLDs were used for each of the following sites: radiologist's eyes, thyroid, gonads with and without shielding apron, and hands. The average dose during carotid angiograms was 2.6, 4.1, 0.4, 4.7, and 7.1 mrads to the eyes, thyroid, gonads with and without .5 mm of lead shielding, and hands, respectively. Average dose during abdominal and peripheral vascular angiographic procedures was 5.2, 7.5, 1.2, 8.5, and 39.9 mrads to the eyes, thyroid, gonads with and without shielding, and hands, respectively. A literature review demonstrates a significant reduction in radiation dose to the angiographer after the advent of automated injectors. Our measured doses for carotid angiography are compatible with contemporary reported values. There was poor correlation with fluoroscopy time and measured dose to the angiographer

Radiation dose during angiographic procedures

International Nuclear Information System (INIS)

Lavoie, Ch.; Rasuli, P.

2001-01-01

The use of angiographic procedures is becoming more prevalent as new techniques and equipment are developed. There have been concerns in the scientific community about the level of radiation doses received by patients, and indirectly by staff, during some of these radiological procedures. The purpose of this study was to assess the level of radiation dose from angiographic procedures to patient at the Ottawa Hospital, General Campus. Radiation dose measurements, using Thermo-Luminescent Dosimeters (TLDs), were performed on more than 100 patients on various procedures. The results show that while the patient dose from the great majority of angiographic procedures is less than 2 Gy, a significant number of procedures, especially interventional procedures may have doses greater than 2 Gy and may lead to deterministic effects. (author)

Missed rib fractures on evaluation of initial chest CT for trauma patients: pattern analysis and diagnostic value of coronal multiplanar reconstruction images with multidetector row CT.

Science.gov (United States)

Cho, S H; Sung, Y M; Kim, M S

2012-10-01

The objective of this study was to review the prevalence and radiological features of rib fractures missed on initial chest CT evaluation, and to examine the diagnostic value of additional coronal images in a large series of trauma patients. 130 patients who presented to an emergency room for blunt chest trauma underwent multidetector row CT of the thorax within the first hour during their stay, and had follow-up CT or bone scans as diagnostic gold standards. Images were evaluated on two separate occasions: once with axial images and once with both axial and coronal images. The detection rates of missed rib fractures were compared between readings using a non-parametric method of clustered data. In the cases of missed rib fractures, the shapes, locations and associated fractures were evaluated. 58 rib fractures were missed with axial images only and 52 were missed with both axial and coronal images (p=0.088). The most common shape of missed rib fractures was buckled (56.9%), and the anterior arc (55.2%) was most commonly involved. 21 (36.2%) missed rib fractures had combined fractures on the same ribs, and 38 (65.5%) were accompanied by fracture on neighbouring ribs. Missed rib fractures are not uncommon, and radiologists should be familiar with buckle fractures, which are frequently missed. Additional coronal imagescan be helpful in the diagnosis of rib fractures that are not seen on axial images.

Diagnostic accuracy of unenhanced, contrast-enhanced perfusion and angiographic MRI sequences for pulmonary embolism diagnosis: results of independent sequence readings

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Revel, Marie Pierre [Hopital Europeen Georges Pompidou, APHP, Departments of Radiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); Hotel-Dieu, Service de Radiologie, Paris (France); Sanchez, Olivier; Meyer, Guy [Hopital Europeen Georges Pompidou, APHP, Respiratory and intensive care and, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); INSERM Unite 765, Paris (France); Lefort, Catherine; Couchon, Sophie; Hernigou, Anne; Frija, Guy [Hopital Europeen Georges Pompidou, APHP, Departments of Radiology, Paris (France); Niarra, Ralph [Hopital Europeen Georges Pompidou, APHP, Clinical Epidemiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); Chatellier, Gilles [Hopital Europeen Georges Pompidou, APHP, Clinical Epidemiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); INSERM CIC-EC E4, Paris (France)

2013-09-15

To independently evaluate unenhanced, contrast-enhanced perfusion and angiographic MR sequences for pulmonary embolism (PE) diagnosis. Prospective investigation, including 274 patients who underwent perfusion, unenhanced 2D steady-state-free-precession (SSFP) and contrast-enhanced 3D angiographic MR sequences on a 1.5-T unit, in addition to CTA (CT angiography). Two independent readers evaluated each sequence independently in random order. Sensitivity, specificity, predictive values and inter-reader agreement were calculated for each sequence, excluding sequences judged inconclusive. Sensitivity was also calculated according to PE location. Contrast-enhanced angiographic sequences showed the highest sensitivity (82.9 and 89.7 %, reader 1 and reader 2, respectively), specificity (98.5 and 100 %) and agreement (kappa value 0.77). Unenhanced angiographic sequences, although less sensitive overall (68.7 and 76.4 %), were sensitive for the detection of proximal PE (92.7 and 100 %) and showed high specificity (96.1 and 99.1 %) and good agreement (kappa value 0.62). Perfusion sequences showed lower sensitivity (75.0 and 79.3 %), specificity (84.8 and 89.7 %) and agreement (kappa value 0.51), and a negative predictive value of 84.8 % at best. Compared with contrast-enhanced angiographic sequences, unenhanced sequences demonstrate lower sensitivity, except for proximal PE, but high specificity and agreement. The negative predictive value of perfusion sequences was insufficient to safely rule out PE. (orig.)

Detection of intracranial aneurysms with 64 channel multidetector row computed tomography: Comparison with digital subtraction angiography

International Nuclear Information System (INIS)

Pozzi-Mucelli, Fabio; Bruni, Stefano; Doddi, Marco; Calgaro, Antonio; Braini, Massimiliano; Cova, Maria

2007-01-01

Purpose: To compare the contribution of 64 channel multidetector row computed tomography angiography (64MDCT-angiography) with digital subtraction angiography (DSA) in the detection of intracranial aneurysms. Methods and materials: Twenty-nine patients (10 males and 19 females, age: 40-84 years; average: 61.9 years) with clinical and imaging findings strongly suggesting the presence of subaracnoid hemorrhage underwent 64MDCT-angiography and DSA with a short interval between the two examinations (less than 12 h-5 days). CT parameters were: 64 mm x 0.5 mm collimation, pitch-0.828 and helical pitch-53. DSA were performed with standard technique (four vessel catheterization) and multiple projections. Axial CT scans as well as maximum intensity projection, volume rendering and multiplanar reformations and angiographic views were independently reviewed by four readers (two for 64MDCT-angiography and two for DSA). Consensus was reached for discordant cases. DSA was considered as the standard of reference. Results: In 29 patients, 28 aneurysms were found (14 patients had 1 aneurysm, 4 patients had 2 aneurysms and 2 patients had 3 aneurysms; in 9 patients no aneurysm were found). 64MDCT-angiography detected 26/28 aneurysms. No false-positive sites were recognized. The sensitivity, specificity, positive and negative predictive values and diagnostic accuracy were, respectively, 92.8, 100, 100, 99.4 and 99.5%. Conclusions: 64MDCT-angiography is helpful in detecting intracranial aneurysms with results similar to those of DSA but with less discomfort and risks for the patients and can be considered for the first line imaging technique. Conventional angiography is still needed in doubtful cases or negative MDCT-angiography associated with a strong clinical suspect

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)

The usefulness of contrast material injection at the dorsal vein of the hand in 64-detecter row helical CT coronary angiography

International Nuclear Information System (INIS)

Kawano, Youji; Yakabe, Kazuaki; Urata, Jungo; Eto, Miyuki; Yamaguchi, Hiroichiro

2011-01-01

In 315 cases of multi detector row CT (MDCT) coronary angiography contrast material were injected at the dorsal vein of the hand. Early 168 cases were used 80 ml of 370 mgI/ml contrast material and later 147 cases were used 350-480 mgI/kg contrast material. In all cases contrast material was injected by 4 ml/sec with post injection of 30-40 ml physiologic saline. The attenuation of RCA No.3 and other coronary arteries or coronary artery bypass graft (CABG) graft was measured. In later cases the usefulness of above 300 HU was 95.2%. In all cases the usefulness was 92.6%. (author)

Dose related, comparative evaluation of a novel bone-subtraction algorithm in 64-row cervico-cranial CT angiography

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Siebert, E.; Bohner, G. [Department of Neuroradiology, Charite Universitary Medicine Berlin (Germany); Dewey, M.; Bauknecht, C. [Department of Radiology, Charite Universitary Medicine Berlin (Germany); Klingebiel, R. [Department of Neuroradiology, Charite Universitary Medicine Berlin (Germany)], E-mail: randolf.klingebiel@charite.de

2010-01-15

Purpose: Comparative evaluation of a low-dose scan protocol for a novel bone-subtraction (BS) algorithm, applicable to 64-row cervico-cranial (cc) CT angiography (MSCTA). Methods and patients: BS algorithm assessment was performed in cadaveric phantom studies by stepwise variation of tube current and head malrotation using a 64-row CT scanner. In order to define minimum dose requirements and the rotation correction capacity, a low dose BS MSCTA protocol was defined and evaluated in 12 patients in comparison to a common manual bone removal algorithm. Standard MIPs of both modalities were evaluated in a blinded manner by two neuroradiologists for image quality composed, of vessel contour sharpness and bony vessel superposition, by using a five-point score each. Effective Dose (E) and data post-processing times were defined. Results: In experimental studies prescan tube current could be cut down to one-sixth of post-contrast scan doses without compromise of bone-subtraction whereas incomplete subtraction appeared from four degrees head malrotation on. Prescan E amounted to additional 1.1 mSv (+25%) in clinical studies. BS MSCTA performed significantly superior in terms of bony superposition for vascular segments C3-C7 (p < 0.001), V1-V2, V3-V4 (p < 0.05, p < 0.001 respectively) and the ophthalmic artery (p < 0.05), whereas vessel contour sharpness in BS MSCTA only proved superior for arterial segments V3-V4 (p < 0.001) and C3-C7 (p < 0.001). MBR MSCTA received higher ratings in vessel contour sharpness for C1-C2 (p < 0.001), callosomarginal artery (p < 0.001), M1, M2, M3 (p < 0.001 each) and the basilar artery (p < 0.001). Reconstruction times amounted to an average of 1.5 (BS MSCTA) and 3 min (MBR MSCTA) respectively. Conclusion: The novel BS algorithm provides superior skull base artery visualisation as compared to common manual bone removal algorithms, increasing the Effective Dose by one-fourth. Yet, inferior vessel contour sharpness was noted intracranially, thus

Dose related, comparative evaluation of a novel bone-subtraction algorithm in 64-row cervico-cranial CT angiography

International Nuclear Information System (INIS)

Siebert, E.; Bohner, G.; Dewey, M.; Bauknecht, C.; Klingebiel, R.

2010-01-01

Purpose: Comparative evaluation of a low-dose scan protocol for a novel bone-subtraction (BS) algorithm, applicable to 64-row cervico-cranial (cc) CT angiography (MSCTA). Methods and patients: BS algorithm assessment was performed in cadaveric phantom studies by stepwise variation of tube current and head malrotation using a 64-row CT scanner. In order to define minimum dose requirements and the rotation correction capacity, a low dose BS MSCTA protocol was defined and evaluated in 12 patients in comparison to a common manual bone removal algorithm. Standard MIPs of both modalities were evaluated in a blinded manner by two neuroradiologists for image quality composed, of vessel contour sharpness and bony vessel superposition, by using a five-point score each. Effective Dose (E) and data post-processing times were defined. Results: In experimental studies prescan tube current could be cut down to one-sixth of post-contrast scan doses without compromise of bone-subtraction whereas incomplete subtraction appeared from four degrees head malrotation on. Prescan E amounted to additional 1.1 mSv (+25%) in clinical studies. BS MSCTA performed significantly superior in terms of bony superposition for vascular segments C3-C7 (p < 0.001), V1-V2, V3-V4 (p < 0.05, p < 0.001 respectively) and the ophthalmic artery (p < 0.05), whereas vessel contour sharpness in BS MSCTA only proved superior for arterial segments V3-V4 (p < 0.001) and C3-C7 (p < 0.001). MBR MSCTA received higher ratings in vessel contour sharpness for C1-C2 (p < 0.001), callosomarginal artery (p < 0.001), M1, M2, M3 (p < 0.001 each) and the basilar artery (p < 0.001). Reconstruction times amounted to an average of 1.5 (BS MSCTA) and 3 min (MBR MSCTA) respectively. Conclusion: The novel BS algorithm provides superior skull base artery visualisation as compared to common manual bone removal algorithms, increasing the Effective Dose by one-fourth. Yet, inferior vessel contour sharpness was noted intracranially, thus

Evaluation of thoracic abnormalities on 64-row multi-detector row CT: Comparison between axial images versus coronal reformations

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Nishino, Mizuki [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave., Boston, MA 02215 (United States)]. E-mail: mnishino@bidmc.harvard.edu; Kubo, Takeshi [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave., Boston, MA 02215 (United States); Kataoka, Milliam L. [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave., Boston, MA 02215 (United States); Gautam, Shiva [Department of General Clinical Research Center and Biometrics, Beth Israel Deaconess Medical Center, 330 Brookline Ave., Boston, MA 02215 (United States); Raptopoulos, Vassilios [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave., Boston, MA 02215 (United States); Hatabu, Hiroto [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave., Boston, MA 02215 (United States)

2006-07-15

Purpose: To evaluate the capability of coronal reformations of chest on 64-row MDCT in demonstrating thoracic abnormalities in comparison with axial images. Materials and methods: Thirty-eight consecutive patients who underwent pulmonary CTA on 64-row MDCT were retrospectively studied with institutional review board (IRB) approval. Contiguous 2 mm axial and coronal images were reviewed independently with a 1-week interval, by consensus reading of two board-certified radiologists. Overall image quality was graded using a five-point scale. Abnormalities in mediastinum, hilum, pulmonary vessels, aorta, heart, esophagus, pleura, chest wall, and lung parenchyma were scored: 1 = definitely absent, 2 = probably absent, 3 = equivocal, 4 probably present, 5 = definitely present. Scores on axial and coronal images were compared using weighted {kappa} analysis. Results: Overall image quality was not different with statistical relevance between axial and coronal images (mean/median scores; 3.7/4; 3.6/4, respectively, P = 0.286, Wilcoxon signed-rank test). Significant agreement was observed between axial and coronal scores (mean weighted {kappa}, 0.661; range, 0.362-1). Agreement was almost perfect for pneumothorax, lung and pleural mass, effusion and consolidation (weighted {kappa} = 0.833-1); substantial for pulmonary embolism, trachea, mediastinal lymphadenopathy and non-skeletal chest wall lesion, heart, esophagus, and emphysema (weighted {kappa}, 0.618-0.799); moderate for atelectasis, mediastinum, hilar nodes, aorta, other lung lesions, skeletal chest wall lesions, linear scarring, nodules >1 cm, pulmonary artery abnormalities and pleural thickening (weighted {kappa}, 0.405-0.592); and fair for nodules <1 cm (weighted {kappa} = 0.362). Conclusion: Coronal reformations on 64-row MDCT had substantial agreement with axial images for evaluation of the majority of thoracic abnormalities.

Evaluation of thoracic abnormalities on 64-row multi-detector row CT: Comparison between axial images versus coronal reformations

International Nuclear Information System (INIS)

Nishino, Mizuki; Kubo, Takeshi; Kataoka, Milliam L.; Gautam, Shiva; Raptopoulos, Vassilios; Hatabu, Hiroto

2006-01-01

Purpose: To evaluate the capability of coronal reformations of chest on 64-row MDCT in demonstrating thoracic abnormalities in comparison with axial images. Materials and methods: Thirty-eight consecutive patients who underwent pulmonary CTA on 64-row MDCT were retrospectively studied with institutional review board (IRB) approval. Contiguous 2 mm axial and coronal images were reviewed independently with a 1-week interval, by consensus reading of two board-certified radiologists. Overall image quality was graded using a five-point scale. Abnormalities in mediastinum, hilum, pulmonary vessels, aorta, heart, esophagus, pleura, chest wall, and lung parenchyma were scored: 1 = definitely absent, 2 = probably absent, 3 = equivocal, 4 probably present, 5 = definitely present. Scores on axial and coronal images were compared using weighted κ analysis. Results: Overall image quality was not different with statistical relevance between axial and coronal images (mean/median scores; 3.7/4; 3.6/4, respectively, P = 0.286, Wilcoxon signed-rank test). Significant agreement was observed between axial and coronal scores (mean weighted κ, 0.661; range, 0.362-1). Agreement was almost perfect for pneumothorax, lung and pleural mass, effusion and consolidation (weighted κ = 0.833-1); substantial for pulmonary embolism, trachea, mediastinal lymphadenopathy and non-skeletal chest wall lesion, heart, esophagus, and emphysema (weighted κ, 0.618-0.799); moderate for atelectasis, mediastinum, hilar nodes, aorta, other lung lesions, skeletal chest wall lesions, linear scarring, nodules >1 cm, pulmonary artery abnormalities and pleural thickening (weighted κ, 0.405-0.592); and fair for nodules <1 cm (weighted κ = 0.362). Conclusion: Coronal reformations on 64-row MDCT had substantial agreement with axial images for evaluation of the majority of thoracic abnormalities

Multidetector-row computed tomography for the preoperative evaluation of axillary nodal status in patients with breast cancer

International Nuclear Information System (INIS)

Ogasawara, Yutaka; Doihara, Hiroyoshi; Shiraiwa, Misaki; Ishihara, Setsuko

2008-01-01

We evaluated the effectiveness of multidetector-row computed tomography (MD-CT) for detecting axillary lymph nodal status (ALNS) in patients with breast cancer. We reviewed 42 patients with breast cancer. A metastatic lymph node on MD-CT was defined as oval or round, with more than 5 mm on the short axis. We evaluated ALNS preoperatively by both palpation and MD-CT findings and performed sentinel lymph node biopsy (SLNB) and complete axillary lymph node dissection (ALND). For establishing the ALNS, MD-CT showed a sensitivity of 76.9%, a specificity of 96.6%, and an accuracy of 90.5%. On the basis of the MD-CT findings, misdiagnosis was made in 4 of the 42 patients, only one of which was false positive. On the other hand, one patient with a histologically negative sentinel lymph node (SLN) result had metastasis only in a non-SLN. Preoperative MD-CT showed a positive node in this patient. Multidetector-row computed tomography assists in identifying women who require ALND without SLNB, with sufficient positive predictive value. False-negative detection by SLNB could be avoided with careful interpretation of the axillary lymph nodes shown by MD-CT. (author)

Single-row versus double-row rotator cuff repair: techniques and outcomes.

Science.gov (United States)

Dines, Joshua S; Bedi, Asheesh; ElAttrache, Neal S; Dines, David M

2010-02-01

Double-row rotator cuff repair techniques incorporate a medial and lateral row of suture anchors in the repair configuration. Biomechanical studies of double-row repair have shown increased load to failure, improved contact areas and pressures, and decreased gap formation at the healing enthesis, findings that have provided impetus for clinical studies comparing single-row with double-row repair. Clinical studies, however, have not yet demonstrated a substantial improvement over single-row repair with regard to either the degree of structural healing or functional outcomes. Although double-row repair may provide an improved mechanical environment for the healing enthesis, several confounding variables have complicated attempts to establish a definitive relationship with improved rates of healing. Appropriately powered rigorous level I studies that directly compare single-row with double-row techniques in matched tear patterns are necessary to further address these questions. These studies are needed to justify the potentially increased implant costs and surgical times associated with double-row rotator cuff repair.

Multidetector row computed tomography of acute pancreatitis: Utility of single portal phase CT scan in short-term follow up

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Kwon, Yongwonn [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of); Park, Hee Sun, E-mail: heesun.park@gmail.com [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of); Kim, Young Jun; Jung, Sung Il; Jeon, Hae Jeong [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of)

2012-08-15

Objective: The purpose of this study is to evaluate the question of whether nonenhanced CT or contrast enhanced portal phase CT can replace multiphasic pancreas protocol CT in short term monitoring in patients with acute pancreatitis. Materials and methods: This retrospective study was approved by the Institutional Review Board. From April 2006 to May 2010, a total of 52 patients having acute pancreatitis who underwent initial dual phase multidetector row CT (unenhanced, arterial, and portal phase) at admission and a short term (within 30 days) follow up dual phase CT (mean interval 10.3 days, range 3-28 days) were included. Two abdominal radiologists performed an independent review of three sets of follow up CT images (nonenhanced scan, single portal phase scan, and dual phase scan). Interpretation of each image set was done with at least 2-week interval. Radiologists evaluated severity of acute pancreatitis with regard to pancreatic inflammation, pancreatic necrosis, and extrapancreatic complication, based on the modified CT severity index. Scores of each image set were compared using a paired t-test and interobserver agreement was evaluated using intraclass correlation coefficient statistics. Results: Mean scores of sum of CT severity index on nonenhanced scan, portal phase scan, and dual phase scan were 5.7, 6.6, and 6.5 for radiologist 1, and 5.0, 5.6, and 5.8 for radiologist 2, respectively. In both radiologists, contrast enhanced scan (portal phase scan and dual phase scan) showed significantly higher severity score compared with that of unenhanced scan (P < 0.05), while portal phase and dual phase scan showed no significant difference each other. The trend was similar regarding pancreatic inflammation and extrapancreatic complications, in which contrast enhanced scans showed significantly higher score compared with those of unenhanced scan, while no significant difference was observed between portal phase scan and dual phase scan. In pancreatic necrosis

Imaging of acute mesenteric ischemia using multidetector CT and CT angiography in a porcine model.

Science.gov (United States)

Rosow, David E; Sahani, Dushyant; Strobel, Oliver; Kalva, Sanjeeva; Mino-Kenudson, Mari; Holalkere, Nagaraj S; Alsfasser, Guido; Saini, Sanjay; Lee, Susanna I; Mueller, Peter R; Fernández-del Castillo, Carlos; Warshaw, Andrew L; Thayer, Sarah P

2005-12-01

Acute mesenteric ischemia, a frequently lethal disease, requires prompt diagnosis and intervention for favorable clinical outcomes. This goal remains elusive due, in part, to lack of a noninvasive and accurate imaging study. Traditional angiography is the diagnostic gold standard but is invasive and costly. Computed tomography (CT) is readily available and noninvasive but has shown variable success in diagnosing this disease. The faster scanning time of multidetector row CT (M.D.CT) greatly facilitates the use of CT angiography (CTA) in the clinical setting. We sought to determine whether M.D.CT-CTA could accurately demonstrate vascular anatomy and capture the earliest stages of mesenteric ischemia in a porcine model. Pigs underwent embolization of branches of the superior mesenteric artery, then imaging by M.D.CT-CTA with three-dimensional reconstruction protocols. After scanning, diseased bowel segments were surgically resected and pathologically examined. Multidetector row CT and CT angiography reliably defined normal and occluded mesenteric vessels in the pig. It detected early changes of ischemia including poor arterial enhancement and venous dilatation, which were seen in all ischemic animals. The radiographic findings--compared with pathologic diagnoses-- predicted ischemia, with a positive predictive value of 92%. These results indicate that M.D.CT-CTA holds great promise for the early detection necessary for successful treatment of acute mesenteric ischemia.

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)

Detection of intracranial aneurysms using three-dimensional multidetector-row CT angiography: Is bone subtraction necessary?

International Nuclear Information System (INIS)

Hwang, Seung Bae; Kwak, Hyo Sung; Han, Young Min; Chung, Gyung Ho

2011-01-01

Purpose: The aim of this study was to evaluate the usefulness of three-dimensional CT angiography (3D CTA) with bone subtraction in a comparison with 3D CTA without bone subtraction for the detection of intracranial aneurysms. Materials and methods: Among 337 consecutive patients who had intracranial aneurysms detected on 3D CTA, 170 patients who underwent digital subtraction angiography (DSA) were included in the study. CTA was performed with a 16-slice multidetector-row CT (MDCT) scanner. We created the 3D reconstruction images with and without bone subtraction by using the volume rendering technique. Three neuroradiologists in a blinded fashion interpreted both 3D CTA images with and without bone subtraction. The diagnostic accuracy of both techniques was evaluated using the alternative free-response receiver operating characteristic (ROC) analysis. The sensitivity and positive predictive value were also evaluated. Results: A total of 200 aneurysms (size: 2-23 mm) were detected in 170 patients. The area under the receiver operating characteristic curve (Az) for 3D CTA with bone subtraction (mean, Az = 0.933) was significantly higher than that for 3D CTA without bone subtraction (mean, Az = 0.879) for all observers (P < 0.05). The sensitivity of 3D CTA with bone subtraction for three observers was 90.0, 92.0 and 92.5%, respectively, while the sensitivity of 3D CTA without bone subtraction was 83.5, 83.5 and 87.5%, respectively. No significant difference in positive predictive value was observed between the two modalities. Conclusions: 3D CTA with bone subtraction showed significantly higher diagnostic accuracy for the detection of intracranial aneurysms as compared to 3D CTA without bone subtraction.

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)

Sensitivity and accuracy of volumetry of pulmonary nodules on low-dose 16- and 64-row multi-detector CT: an anthropomorphic phantom study

International Nuclear Information System (INIS)

Xie, Xueqian; Zhao, Yingru; Ooijen, Peter M.A. van; Vliegenthart, Rozemarijn; Snijder, Roland A.; Greuter, Marcel J.W.; Jong, Pim A. de; Oudkerk, Matthijs; Bock, Geertruida H. de

2013-01-01

To assess the sensitivity of detection and accuracy of volumetry by manual and semi-automated quantification of artificial pulmonary nodules in an anthropomorphic thoracic phantom on low-dose CT. Fifteen artificial spherical nodules (diameter 3, 5, 8, 10 and 12 mm; CT densities -800, -630 and +100 HU) were randomly placed inside an anthropomorphic thoracic phantom. The phantom was examined on 16- and 64-row multidetector CT with a low-dose protocol. Two independent blinded observers screened for pulmonary nodules. Nodule diameter was measured manually, and volume calculated. For solid nodules (+100 HU), diameter and volume were also evaluated by semi-automated software. Differences in observed volumes between the manual and semi-automated method were evaluated by a t-test. Sensitivity was 100 % for all nodules of >5 mm and larger, 60-80 % for solid and 0-20 % for non-solid 3-mm nodules. No false-positive nodules but high inter-observer reliability and inter-technique correlation were found. Volume was underestimated manually by 24.1 ± 14.0 % for nodules of any density, and 26.4 ± 15.5 % for solid nodules, compared with 7.6 ± 8.5 % (P 5 mm in diameter. Semi-automated volumetry yielded more accurate nodule volumes than manual measurements. (orig.)

Angiographic appearances of rare renal tumours

International Nuclear Information System (INIS)

Schmidt, M.; Taenzer, V.

1980-01-01

Oncocytomas, called oxyphil proximal tubular adenomas in the Anglo Saxon literature, and benign hypernephromas are non-malignant, usually symptomless, rare tumours belonging to the renal adenomas. Oncocytomas have angiographic appearances sufficiently uniform to permit a tentative diagnosis. Histologically benign hypernephromas do not possess characteristic angiographic appearances and, in the presence of tumour in the renal vein or necrotic avascular areas, must be regarded as potentially malignant. (orig.) [de

Spontaneous vertebral dissection: Clinical, conventional angiographic, CT, and MR findings

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Provenzale, J.M.; Morgenlander, J.C. [Duke Univ. Medical Center, Durham, NC (United States); Gress, D. [Univ. of California, San Francisco, CA (United States)

1996-03-01

The purpose of this study was to determine if typical clinical and neuroradiologic patterns exist in patients with spontaneous vertebral artery (VA) dissection. The medical records and neuroradiologic examinations of 14 patients with spontaneous VA dissection were reviewed. The medical records were examined to exclude patients with a history of trauma and to record evidence of a nontratimatic precipitating event ({open_quotes}trivial trauma{close_quotes}) and presence of possible risk factors such as hypertension. All patients under-went conventional angiography, 13 either CT or MRI (II both CT and MRI), and 3 MRA. Conventional arteriograrris were evaluated for dissection site, evidence of fibromuscular dysplasia, luminal stenosis or occlusion, and pseudoaneurysm formation, CT examinations for the presence of infarction or subarachnoid hemorrhage, MR examinations for the presence of infarction or arterial signal abnormality, and MR angiograms for abnormality of the arterial signal column. Seven patients had precipitating events within 24 h of onset of symptoms that may have been causative of dissection and five had hypertension. At catheter angiography, two patients had dissections in two arteries (both VAs in one patient, VA and internal carotid artery in one patient), giving a total of 15 VAs with dissection. Dissection sites included V1 in four patients, V2 in one patient, V3 in three patients, V4 in six patients, and both V3 and V4 in one patient. Luminal stenosis was present in 13 VAs, occlusion in 2, pseudoaneurysm in 1, and evidence of fibromuscular dysplasia in 1. Posterior circulation infarcts were found on CT or MR in five patients. Subarachnoid hemorrhage was found on CT in two patients and by lumbar puncture alone in two patients. Abnormal periarterial signal on MRI was seen in three patients. MRA demonstrated absent VA signal in one patient, pseudoaneurysm in one, and a false-negative examination in one.

CT pulmonary angiography using 64-row multi-slice spiral CT: a comparative study in low tube voltage setting combined with personalized contrast agent application

International Nuclear Information System (INIS)

Zhou Xuhui; Peng Zhenpeng; Zheng Lili; Li Shurong; Yang Zhiyun; Meng Quanfei; Chen Xing

2009-01-01

Objective: To investigate the feasibility of the low tube voltage setting and personalized contrast agent application in 64-row multi-slice spiral CT pulmonary angiography. Methods: Ninety patients with high risk of pulmonary artery embolism were sequentially enrolled in the study and divided into 3 groups employing completely randomized design: (l)Regular group included 30 patients using 120 kV and fixed dose of 70 ml contrast agent, (2)Another 30 patients were in 120 kV group, using 120 kV and the contrast amount was determined according to the patient weight (1.0 ml/kg), (3) The remaining 30 patients were included in 100 kV group, using 100 kV and the contrast amount was also determined according to the patient weight(1.0 ml/kg). Administration of contrast agent was completed within 20 seconds for all the patients, followed by 20 ml of saline. The objective and subjective indexes for assessing CT image quality, CT dose index volume (CTDIvol) and effective received dose (ERD) were compared between 120 kV group and 100 kV group; then the contrast media volume, injection rate, objective CT image indexes and subjective indexes for image quality was compared between the 100 kV group and regular group. The variance analysis and post hoc test were employed for the statistical analysis. Results: Compared with 120 kV group (3.4±0.7), the image quality of 100 kV group (5.2±1.8) had higher noise (52.9%), but subjective index for the image quality demonstrated no differences (q=0.272, P=0.063) in mediastinum window while CTDIvol and ERD decreased for 34.9% [(9.5±0.0) vs (14.6±0.0) mGy] and 36.8% [(3.8±0.6) vs (2.4±0.4) mSv]. The mean CT values on pulmonary artery of 100 kV group[ (269.2±54.7) HU] were 13.4% (31.8/237.4) higher than the 120 kV group [(237.4±62.9)HU], but there was no statistical differences compared to normal group (q=0.172,P=0.260). Conclusion: Using low kV setting (100 kV) to reduce radiation dose is proved to be effective and feasible in 64-MSCT

Imaging of Acute Mesenteric Ischemia Using Multidetector CT and CT Angiography in a Porcine Model

OpenAIRE

Rosow, David E.; Sahani, Dushyant; Strobel, Oliver; Kalva, Sanjeeva; Mino-Kenudson, Mari; Holalkere, Nagaraj S.; Alsfasser, Guido; Saini, Sanjay; Lee, Susanna I.; Mueller, Peter R.; Castillo, Carlos Fernández-del; Warshaw, Andrew L.; Thayer, Sarah P.

2005-01-01

Acute mesenteric ischemia, a frequently lethal disease, requires prompt diagnosis and intervention for favorable clinical outcomes. This goal remains elusive due, in part, to lack of a noninvasive and accurate imaging study. Traditional angiography is the diagnostic gold standard but is invasive and costly. Computed tomography (CT) is readily available and noninvasive but has shown variable success in diagnosing this disease. The faster scanning time of multidetector row CT (M.D.CT) greatly f...

Left ventricular functional parameters and geometric patterns in Korean adults on coronary CT angiography with a 320-detector-row CT scanner

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Kang, Eun Ju; Lee, Ki Nam; Cho, Won Jin; Kim, Young Dae [College of Medicine, Dong-A University, Busan (Korea, Republic of); Shin, Kyung Min; Lim, Jae Kwang; Lee, Jong Min [Dept. of Radiology, Kyungpook National University, Daegu (Korea, Republic of)

2017-08-01

To assess the normal reference values of left ventricle (LV) functional parameters in Korean adults on coronary CT angiography (CCTA) with a 320-detector-row CT scanner, and to analyze sex-related differences and correlations with various clinical characteristics. This study retrospectively enrolled 172 subjects (107 men and 65 women; age, 58 ± 10.9 years; body surface area [BSA], 1.75 ± 0.2 m{sup 2}) who underwent CCTA without any prior history of cardiac disease. The following parameters were measured by post-processing the CT data: LV volume, LV functional parameters (ejection fraction, stroke volume, cardiac output, etc.), LV myocardial mass, LV inner diameter, and LV myocardial thickness (including septal wall thickness [SWT], posterior wall thickness [PWT], and relative wall thickness [RWT = 2 × PWT / LV inner diameter]). All of the functional or volumetric parameters were normalized using the BSA. The general characteristics and co-morbidities for the enrolled subjects were recorded, and the correlations between these factors and the LV parameters were then evaluated. The LV myocardial thickness (SWT, 1.08 ± 0.18 cm vs. 0.90 ± 0.17 cm, p < 0.001; PWT, 0.91 ± 0.15 cm vs. 0.78 ± 0.10 cm, p < 0.001; RWT, 0.38 ± 0.08 cm vs. 0.33 ± 0.05 cm, p < 0.001), LV volume (LV end-diastolic volume, 112.9 ± 26.1 mL vs. 98.2 ± 21.0 mL, p < 0.001; LV end-systolic volume, 41.7 ± 14.7 mL vs. 33.7 ± 12.2 mL, p = 0.001) and mass (145.0 ± 29.1 g vs. 107.9 ± 20.0 g, p < 0.001) were significantly greater in men than in women. However, these differences were not significant after normalization using BSA, except for the LV mass (LV mass index, 79.6 ± 14.0 g/m{sup 2} vs. 66.2 ± 11.0 g/m{sup 2},p < 0.001). The cardiac output and ejection fraction were not significantly different between the men and women (cardiac output, 4.3 ± 1.0 L/min vs. 4.2 ± 0.9 L/min, p = 0.452; ejection fraction, 63.4 ± 7.7% vs. 66.4 ± 7.6%, p = 0.079). Most of the LV parameters were

Angiographic-CT-FDG-Pathologic Correlations of the Incidentally Discovered Adrenal Mass

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Bi-Fang Lee

2011-01-01

Full Text Available During abdominal ultrasonography of a 37-year-old man a 3.2 cm hypoechoic mass in the right hepatic lobe was found incidentally. This prompted an abdominal CT, an FDG PET/CT, and an angiography to evaluate the nature of the mass. Laboratory data showed positive anti-HBs/anti-HBe, and negative HCV antibody. The alfa-fetoprotein and liver function tests were within normal limits. Contrast-enhanced CT found an enhanced hepatic tumor and primary hepatocellular carcinoma was suspected. PET/CT revealed no abnormal FDG accumulation in the right hepatic mass. The digital subtraction angiographies of the right inferior phrenic artery and right renal artery revealed a hypervascular tumor in the right adrenal gland. Therefore, a diagnosis of a right adrenal tumor was made. Serum aldosterone, serum cortisol, and urine vanillylmandelic acid, and catecholamine were all within normal limits. Laparoscopic right adrenalectomy was performed and adrenal cortical adenoma was diagnosed on a histological study.

Angiographic findings of congenital vascular malformation in soft tissue

International Nuclear Information System (INIS)

Choi, Dae Seob; Park, Jae Hyung; Han, Joon Koo; Chung, Jin Wook; Moon, Woo Kyung; Han, Man Chung

1994-01-01

We evaluated the clinical, plain radiographic, and angiographic findings of congenital vascular malformation of the soft tissue. Retrospective analysis was performed in 36 patients. Pathological diagnosis was done in 25 patients by surgery and the others were clinically and angiographically diagnosed. On the basis of angiographic findings, we classified the lesions to three groups as arteriovenous malformation (AVM), hemangioma, and venous malformation. In pathologically proven 25 cases, we compared the angiographic diagnosis with the pathologic diagnosis. By angiographic classification, AVM was 13 cases, hemangioma 16 cases, and venous malformation 7 cases. The locations of the lesions were upper extremities in 14 cases, lower extremities in 20 cases, both extremities in 1 case, and back in 1 case. Clinical findings were bruit and thrill in 13 cases(12 AVMs,1 hemangioma) and varicosities in 16 cases(11 AVMs, 3 hemangiomas and 2 venous malformations). The varicosities in AVM were pulsating nature, but not in hemangioma and venous malformation. The concordance rate of the angiographic and pathologic diagnosis was 100%(6/6) in AVM, 71%(10/14) in hemangioma and 60% (3/5) in venous malformation. We think that angiography is an essential study for accurate diagnosis and appropriate treatment of congenital vascular malformation

Preoperative assessment of hilar cholangiocarcinoma using multidetector-row CT. Correlation with histopathological findings

International Nuclear Information System (INIS)

Watadani, Takeyuki; Akahane, Masaaki; Ohtomo, Kuni; Yoshikawa, Takeharu

2008-01-01

Our aim was to investigate the diagnostic reliability of multidetector-row computed tomography (MDCT) for preoperative assessment of local tumoral spread in hilar cholangiocarcinoma. Thirteen of 30 consecutive patients with hilar cholangiocarcinoma who underwent surgery, excluding 17 patients who underwent biliary drainage or preoperative portal embolization, were retrospectively evaluated. Using MDCT systems of 4 detector rows or 16 detector rows, plain and dynamic contrast-enhanced images of three phases were obtained. Extent of tumor spread and lymph node metastasis were assessed with MDCT and compared with histopathological findings. The Bismuth-Corlette classification of hilar cholangiocarcinoma with MDCT were type I, 1 patient; type IIIa, 3 patients; type IIIb, 4 patients; and type IV, 5 patients; those with histopathological findings were type I, 1 patient; type IIIa, 2 patients; type IIIb, 4 patients; and type IV, 6 patients. One patient diagnosed as type IIIa with MDCT was pathologically diagnosed as type IV. Accuracy of MDCT in tumoral spread was 92.3%, although that of lymph node metastasis was 54%. MDCT is likely to play an important role in evaluation of focal lesion spread especially in intrapancreatic tumor invasion, although a greater number of cohort cases are necessary to clearly define its role. (author)

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.

Using multidetector-row CT in neonates with complex congenital heart disease to replace diagnostic cardiac catheterization for anatomical investigation: initial experiences in technical and clinical feasibility

International Nuclear Information System (INIS)

Lee, Tain; Tsai, I.C.; Chen, Min-Chi; Fu, Yun-Ching; Jan, Sheng-Lin; Wang, Chung-Chi; Chang, Yen

2006-01-01

Echocardiography is the first-line modality for the investigation of neonatal congenital heart disease. Diagnostic cardiac catheterization, which has a small but recognized risk, is usually performed if echocardiography fails to provide a confident evaluation of the lesions. To verify the technical and clinical feasibilities of replacing diagnostic cardiac catheterization with multidetector-row CT (MDCT) in neonatal complex congenital heart disease. Over a 1-year period we prospectively enrolled all neonates with complex congenital heart disease referred for diagnostic cardiac catheterization after initial assessment by echocardiography. MDCT was performed using a 40-detector-row CT scanner with dual syringe injection. A multidisciplinary congenital heart disease team evaluated the MDCT images and decided if further diagnostic cardiac catheterization was necessary. The accuracy of MDCT in detecting separate cardiovascular anomalies and bolus geometry of contrast enhancement were calculated. A total of 14 neonates were included in the study. No further diagnostic cardiac catheterization was needed in any neonate. The accuracy of MDCT in diagnosing separate cardiovascular anomalies was 98% (53/54) with only one atrial septal defect missed in a patient with coarctation syndrome. The average cardiovascular enhancement in evaluated chambers was 471 HU. No obvious beam-hardening artefact was observed. The technical and clinical feasibility of MDCT in complex congenital heart disease in neonates is confirmed. After initial assessment with echocardiography, MDCT could probably replace diagnostic cardiac catheterization for further anatomical clarification in neonates. (orig.)

Flat-Panel Computed Tomography (DYNA-CT) in Neuroradiology. From High-Resolution Imaging of Implants to One-Stop-Shopping for Acute Stroke.

Science.gov (United States)

Doerfler, A; Gölitz, P; Engelhorn, T; Kloska, S; Struffert, T

2015-10-01

Originally aimed at improving standard radiography by providing higher absorption efficiency and a wider dynamic range, flat-panel detector technology has meanwhile got widely accepted in the neuroradiological community. Especially flat-panel detector computed tomography (FD-CT) using rotational C-arm mounted flat-panel detector technology is capable of volumetric imaging with a high spatial resolution. By providing CT-like images of the brain within the angio suite, FD-CT is able to rapidly visualize hemorrhage and may thus improve complication management without the need of patient transfer. As "Angiographic CT" FD-CT may be helpful during many diagnostic and neurointerventional procedures and for noninvasive monitoring and follow-up. In addition, spinal interventions and high-resolution imaging of the temporal bone might also benefit from FD-CT. Finally, using novel dynamic perfusion and angiographic protocols, FD-CT may provide functional information on brain perfusion and vasculature with the potential to replace standard imaging in selected acute stroke patients.

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

Functional and structural outcomes of single-row versus double-row versus combined double-row and suture-bridge repair for rotator cuff tears.

Science.gov (United States)

Mihata, Teruhisa; Watanabe, Chisato; Fukunishi, Kunimoto; Ohue, Mutsumi; Tsujimura, Tomoyuki; Fujiwara, Kenta; Kinoshita, Mitsuo

2011-10-01

Although previous biomechanical research has demonstrated the superiority of the suture-bridge rotator cuff repair over double-row repair from a mechanical point of view, no articles have described the structural and functional outcomes of this type of procedure. The structural and functional outcomes after arthroscopic rotator cuff repair may be different between the single-row, double-row, and combined double-row and suture-bridge (compression double-row) techniques. Cohort study; Level of evidence, 3. There were 206 shoulders in 201 patients with full-thickness rotator cuff tears that underwent arthroscopic rotator cuff repair. Eleven patients were lost to follow-up. Sixty-five shoulders were repaired using the single-row, 23 shoulders using the double-row, and 107 shoulders using the compression double-row techniques. Clinical outcomes were evaluated at an average of 38.5 months (range, 24-74 months) after rotator cuff repair. Postoperative cuff integrity was determined using Sugaya's classification of magnetic resonance imaging (MRI). The retear rates after arthroscopic rotator cuff repair were 10.8%, 26.1%, and 4.7%, respectively, for the single-row, double-row, and compression double-row techniques. In the subcategory of large and massive rotator cuff tears, the retear rate in the compression double-row group (3 of 40 shoulders, 7.5%) was significantly less than those in the single-row group (5 of 8 shoulders, 62.5%, P row group (5 of 12 shoulders, 41.7%, P row and suture-bridge techniques, which had the lowest rate of postoperative retear, is an effective option for arthroscopic repair of the rotator cuff tendons because the postoperative functional outcome in patients with a retear is inferior to that without retear.

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.)

Incidence of retear with double-row versus single-row rotator cuff repair.

Science.gov (United States)

Shen, Chong; Tang, Zhi-Hong; Hu, Jun-Zu; Zou, Guo-Yao; Xiao, Rong-Chi

2014-11-01

Rotator cuff tears have a high recurrence rate, even after arthroscopic rotator cuff repair. Although some biomechanical evidence suggests the superiority of the double-row vs the single-row technique, clinical findings regarding these methods have been controversial. The purpose of this study was to determine whether the double-row repair method results in a lower incidence of recurrent tearing compared with the single-row method. Electronic databases were systematically searched to identify reports of randomized, controlled trials (RCTs) comparing single-row with double-row rotator cuff repair. The primary outcome assessed was retear of the repaired cuff. Secondary outcome measures were the American Shoulder and Elbow Surgeons (ASES) shoulder score, the Constant shoulder score, and the University of California, Los Angeles (UCLA) score. Heterogeneity between the included studies was assessed. Six studies involving 428 patients were included in the review. Compared with single-row repair, double-row repair demonstrated a lower retear incidence (risk ratio [RR]=1.71 [95% confidence interval (CI), 1.18-2.49]; P=.005; I(2)=0%) and a reduced incidence of partial-thickness retears (RR=2.16 [95% CI, 1.26-3.71]; P=.005; I(2)=26%). Functional ASES, Constant, and UCLA scores showed no difference between single- and double-row cuff repairs. Use of the double-row technique decreased the incidence of retears, especially partial-thickness retears, compared with the single-row technique. The functional outcome was not significantly different between the 2 techniques. To improve the structural outcome of the repaired rotator cuff, surgeons should use the double-row technique. However, further long-term RCTs on this topic are needed. Copyright 2014, SLACK Incorporated.

Angiographic diagnosis of the carotid artery pseudoaneurysm

International Nuclear Information System (INIS)

Qi Yueyong; Zou Liguang; Dai Shuhua; Tan Yinghui; Li Zhongyu; Zhou Zheng

2004-01-01

Objective: To create a further understanding of the angiographic features of the carotid artery pseudoaneurysm (CAPA) and to explore the clinical diagnostic value of angiography. Methods: Sixteen cases of CAPA with clinical and angiographic data were analyzed retrospectively. The angiographic appearances in all of the patients were observed dynamically and precisely with a double blind method by two experienced radiologists together and formed a consensus interpretation. Results: Angiography provided a definite diagnosis for all cases. The parent arteries included the common carotid artery (1 case), common carotid artery bifurcation (9 cases), internal carotid artery (5 cases) and external carotid artery (1 case). The angiographic features of the CAPA were: All cases showed the contrast media retension in the aneurysms; turbulent flow within aneurysm in 9 cases; the 'jetting sign' at the leak of the parent artery in 7 cases; increase angulation of the bifurcation of internal and external carotid arteries in 12 cases. Conclusions: Angiography is the most valuable examination method in diagnosis of CAPA, and it can not only provide definite diagnosis, but also play an important role in selection of therapeutic plan. (authors)

Sensitivity and accuracy of volumetry of pulmonary nodules on low-dose 16- and 64-row multi-detector CT: an anthropomorphic phantom study

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Xie, Xueqian; Zhao, Yingru; Ooijen, Peter M.A. van; Vliegenthart, Rozemarijn [University of Groningen, University Medical Center Groningen, Department of Radiology, EB44, P.O. Box 30.001, Groningen (Netherlands); University of Groningen, University Medical Center Groningen, Center for Medical Imaging-North East Netherlands, Department of Radiology, Groningen (Netherlands); Snijder, Roland A.; Greuter, Marcel J.W. [University of Groningen, University Medical Center Groningen, Department of Radiology, EB44, P.O. Box 30.001, Groningen (Netherlands); Jong, Pim A. de [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Oudkerk, Matthijs [University of Groningen, University Medical Center Groningen, Center for Medical Imaging-North East Netherlands, Department of Radiology, Groningen (Netherlands); Bock, Geertruida H. de [University of Groningen, University Medical Center Groningen, Department of Epidemiology, Groningen (Netherlands)

2013-01-15

To assess the sensitivity of detection and accuracy of volumetry by manual and semi-automated quantification of artificial pulmonary nodules in an anthropomorphic thoracic phantom on low-dose CT. Fifteen artificial spherical nodules (diameter 3, 5, 8, 10 and 12 mm; CT densities -800, -630 and +100 HU) were randomly placed inside an anthropomorphic thoracic phantom. The phantom was examined on 16- and 64-row multidetector CT with a low-dose protocol. Two independent blinded observers screened for pulmonary nodules. Nodule diameter was measured manually, and volume calculated. For solid nodules (+100 HU), diameter and volume were also evaluated by semi-automated software. Differences in observed volumes between the manual and semi-automated method were evaluated by a t-test. Sensitivity was 100 % for all nodules of >5 mm and larger, 60-80 % for solid and 0-20 % for non-solid 3-mm nodules. No false-positive nodules but high inter-observer reliability and inter-technique correlation were found. Volume was underestimated manually by 24.1 {+-} 14.0 % for nodules of any density, and 26.4 {+-} 15.5 % for solid nodules, compared with 7.6 {+-} 8.5 % (P < 0.01) semi-automatically. In an anthropomorphic phantom study, the sensitivity of detection is 100 % for nodules of >5 mm in diameter. Semi-automated volumetry yielded more accurate nodule volumes than manual measurements. (orig.)

Double-row vs single-row rotator cuff repair: a review of the biomechanical evidence.

Science.gov (United States)

Wall, Lindley B; Keener, Jay D; Brophy, Robert H

2009-01-01

A review of the current literature will show a difference between the biomechanical properties of double-row and single-row rotator cuff repairs. Rotator cuff tears commonly necessitate surgical repair; however, the optimal technique for repair continues to be investigated. Recently, double-row repairs have been considered an alternative to single-row repair, allowing a greater coverage area for healing and a possibly stronger repair. We reviewed the literature of all biomechanical studies comparing double-row vs single-row repair techniques. Inclusion criteria included studies using cadaveric, animal, or human models that directly compared double-row vs single-row repair techniques, written in the English language, and published in peer reviewed journals. Identified articles were reviewed to provide a comprehensive conclusion of the biomechanical strength and integrity of the repair techniques. Fifteen studies were identified and reviewed. Nine studies showed a statistically significant advantage to a double-row repair with regards to biomechanical strength, failure, and gap formation. Three studies produced results that did not show any statistical advantage. Five studies that directly compared footprint reconstruction all demonstrated that the double-row repair was superior to a single-row repair in restoring anatomy. The current literature reveals that the biomechanical properties of a double-row rotator cuff repair are superior to a single-row repair. Basic Science Study, SRH = Single vs. Double Row RCR.

Clinical study of acute cerebral infarction with a midline shift on the CT scan

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Takemae, T; Mizukami, M; Kin, H; Kawase, T; Araki, G [Mihara Memorial Hospital, Isezaki, Gunma (Japan)

1978-12-01

Twenty-one cases of acute cerebral infarction with a midline shift on the CT scan were studied with respect to the development of the midline shift, the angiographic findings, the clinical pictures and the outcome of these patients. The CT findings of hemorrhagic infarction were also studied. No cases showed a midline shift on a CT scan taken within 6 hours after the onset. A midline shift was, however, noted as early as 9 hours after the onset, and it reached its peak between the 2nd and 7th day of the onset. It gradually disappeared by the end of the third week. Hemorrhagic infarction was diagnosed in 6 patients by either spinal tap or autopsy. The CT findings of these hemorrhagic infarction were divided into two types, solid hemorrhages with an unequivocal high density within the low-density area, and small, scattered hemorrhagic of almost the same density as normal brain tissue within the low-density area. In 19 of 21 patients, an round-edged occlusion and/or embolus were observed on the initial angiograms. The recanalization of the occluded vessels was proved in 10 of 14 patients by subsequent angiographic studies. Twenty of 21 patients showed a sudden development of neurological symptoms, and 15 patients had a history of various kinds of heart disease, such as atrial fibrillation, valvular heart disease and myocardial infarction. The patients had atrial fibrillation on EKG on admission. These angiographic findings and clinical pictures strongly suggest that the infarction with a midline shift on the CT scan may be caused by a cerebral embolism of cardiac origin. Eight patients died of cerebral herniation between the 2nd and 6th day of the onset. Taking these poor outcomes into consideration, surgical as well as medical decompression of the brain would seem to be most important when the CT scan shows a midline shift.

Angiographic features of rapidly involuting congenital hemangioma (RICH)

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Konez, Orhan; Burrows, Patricia E. [Department of Radiology, Children' s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Mulliken, John B. [Division of Plastic Surgery, Children' s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Fishman, Steven J. [Department of Pediatric Surgery, Children' s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Kozakewich, Harry P.W. [Department of Pathology, Children' s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States)

2003-01-01

Rapidly involuting congenital hemangioma (RICH) is a recently recognized entity in which the vascular tumor is fully developed at birth and undergoes rapid involution. Angiographic findings in two infants with congenital hemangioma are reported and compared with a more common postnatal infantile hemangioma and a congenital infantile fibrosarcoma. Congenital hemangiomas differed from infantile hemangiomas angiographically by inhomogeneous parenchymal staining, large and irregular feeding arteries in disorganized patterns, arterial aneurysms, direct arteriovenous shunts, and intravascular thrombi. Both infants had clinical evidence of a high-output cardiac failure and intralesional bleeding. This congenital high-flow vascular tumor is difficult to distinguish angiographically from arteriovenous malformation and congenital infantile fibrosarcoma. (orig.)

Coronary imaging quality in routine ECG-gated multidetector CT examinations of the entire thorax: preliminary experience with a 64-slice CT system in 133 patients

International Nuclear Information System (INIS)

Delhaye, Damien; Remy-Jardin, Martine; Salem, Randa; Teisseire, Antoine; Khalil, Chadi; Remy, Jacques; Delannoy-Deken, Valerie; Duhamel, Alain

2007-01-01

To evaluate image quality in the assessment of the coronary arteries during routine ECG-gated multidetector CT (MDCT) of the chest. One hundred and thirty three patients in sinus rhythm underwent an ECG-gated CT angiographic examination of the entire chest without β-blockers with a 64-slice CT system. In 127 patients (95%), it was possible to assess the coronary arteries partially or totally; coronary artery imaging failed in six patients (5%), leading to a detailed description of the coronary arteries in 127 patients. Considering ten coronary artery segments per patient, 75% of coronary segments were assessable (948/1270 segments). When the distal segments were excluded from the analysis (i.e., seven coronary segments evaluated per patient), the percentage of assessable segments was 86% (768/889 proximal and mid coronary segments) and reached 93% (474/508) when assessing proximal segments exclusively. The mean number of assessable segments was significantly higher in patients with a heart rate ≤80 bpm (n=95) than in patients with a heart rate >80 bpm (n=38) (p<0.002). Proximal and mid-coronary segments can be adequately assessed during a whole-chest ECG-gated CT angiographic examination without administration of β-blockers in patients with a heart rate below 80 bpm. (orig.)

Early Angiographic Resolution of Cerebral Vasospasm with High Dose Intravenous Milrinone Therapy

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F. A. Zeiler

2015-01-01

Full Text Available Background. Treatment of symptomatic delayed cerebral ischemia (DCI after subarachnoid hemorrhage (SAH is difficult. Recent studies suggest intravenous (IV high dose milrinone as a potential therapy. The timing to angiographic response with this is unclear. Methods. We reviewed the chart of one patient admitted for SAH who developed symptomatic DCI and was treated with high dose IV milrinone. Results. A 66-year-old female was admitted with a Hunt and Hess clinical grade 4, World Federation of Neurological Surgeons (WFNS clinical grade 4, and SAH secondary to a left anterior choroidal artery aneurysm which was clipped. After bleed day 6, the patient developed symptomatic DCI. We planned for angioplasty of the proximal segments. We administered high dose IV milrinone bolus followed by continuous infusion which led to clinical improvement prior to angiography. The angiogram performed 1.5 hours after milrinone administration displayed resolution of the CT angiogram and MRI based cerebral vasospasm such that further intra-arterial therapy was aborted. She completed 6 days of continuous IV milrinone therapy, was transferred to the ward, and subsequently rehabilitated. Conclusions. High dose IV milrinone therapy for symptomatic DCI after SAH can lead to rapid neurological improvement with dramatic early angiographic improvement of cerebral vasospasm.

CT and MR angiography

International Nuclear Information System (INIS)

Bert, A.L.; Marshal, G.

1995-01-01

CT-angiography is a new vessel imaging technique based on the volumetric scanning of the region of interst during the first pass of IV bolus injection of contrast medium. MR-angiography is a titally noninvasive technique. The differentiation of flowing blood from the adjecent stationary tissues is based on the detection of blood motion. The flowing blood is highlighted with white light. CT- and MR-angiographic techniques are used to establish% stenoses and occlusions in intracranial arteries; aneurisms; trombosis of intracranial veins and venous angioma; diseases of neck vessels, thoracic vessels, abdominal vessels. Blood flow direction in cirrotic patients with portal hypertension can be determined in the portal vein, as well as the presence of thrombosis

Multidetector-row CT finding of gastric cystic lymphangioma: A case report

International Nuclear Information System (INIS)

Kang, Tae Wook; Lee, Soon Jin; Song, Hye Jong

2008-01-01

Cystic lymphangioma is a rare benign submucosal tumor of the stomach thought to originate from sequestered lymphatic tissue that fails to communicate with the normal lymphatic system. The most commonly used method of evaluation for cystic lymphangioma of the stomach is an endoscopic ultrasonography. We report the multidetector-row computed tomography findings of a cystic lymphangioma of the stomach in a 46-year-old man along with a literature review

Exposure doses to angiographers during interventional angiography

International Nuclear Information System (INIS)

Fukutomi, Yukimi; Yasuhara, Yoshifumi; Sugata, Shigenori; Fujii, Takashi; Kawakami, Toshiaki; Ikezoe, Junpei

1997-01-01

We report the exposure doses to angiographers during interventional angiography and the protective efficacy of protective aprons against X-rays in this study. The first (main) angiographer was exposed to the maximum dose of 1 μSv/min at the left chest area and lower abdominal area inside the protective apron. The second (assistant) angiographer was exposed to the maximum dose of 2 μSv/min at the left chest area and 1 μSv/min at the lower abdominal area. X-ray transmission ratio of the protective apron was 4.9 percent or less for UL25L, O percent for 0.35 mmPb and 4.3 percent or less for 0.5 mmPb. These results were lower than the dose equivalent limit based on the laws and ordinances. The protection capacities of these protective aprons proved to be sufficient. The exposure dose at the left extremity area outside the protective apron, however, was 24 times higher than at the left chest area inside. The data showed that it was not protected from scattered X-rays outside the protective apron. It is imperative to consider secondary protective material for the area outside the protective apron. Considering the risk of radiation, we need to better control exposure to angiographers. (author)

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

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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.)

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.)

Clinical application of digital angiographic system DIGITEX2400

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Kawai, Masumi; Tanaka, Shuji; Fujino, Yoshiyuki; Yasumi, Masayuki (Shimadzu Corp., Kyoto (Japan))

1992-10-01

Digital angiography (DA) has been of widespread use clinically, and it has attracted considerable attention in angiographic examination today. And under the condition of the spread of interventional angiography, not only high quality image but also ease of operation are required to the system. The clinical usefullness of digital angiographic system DIGITEX2400 are reported in this paper. (author).

Clinical application of digital angiographic system DIGITEX2400

International Nuclear Information System (INIS)

Kawai, Masumi; Tanaka, Shuji; Fujino, Yoshiyuki; Yasumi, Masayuki

1992-01-01

Digital angiography (DA) has been of widespread use clinically, and it has attracted considerable attention in angiographic examination today. And under the condition of the spread of interventional angiography, not only high quality image but also ease of operation are required to the system. The clinical usefullness of digital angiographic system DIGITEX2400 are reported in this paper. (author)

Comparison of CT and MRI in diagnosis of cerebrospinal leak induced by multiple fractures of skull base

International Nuclear Information System (INIS)

Wang, Xuhui; Xu, Minhui; Liang, Hong; Xu, Lunshan

2011-01-01

Multiple basilar skull fracture and cerebrospinal leak are common complications of traumatic brain injury, which required a surgical repair. But due to the complexity of basilar skull fracture after severe trauma, preoperatively an exact radiological location is always difficult. Multi-row spiral CT and MRI are currently widely applied in the clinical diagnosis. The present study was performed to compare the accuracy of cisternography by multi-row spiral CT and MRI in the diagnosis of cerebrospinal leak. A total of 23 patients with multiple basilar skull fracture after traumatic brain injury were included. The radiological and surgical data were retrospectively analyzed. 64-row CT (mm/row) scan and three-dimensional reconstruction were performed in 12 patients, while MR plain scan and cisternography were performed in another 11 patients. The location of cerebrospinal leak was diagnosed by 2 experienced physicians majoring neurological radiology. Surgery was performed in all patients. The cerebrospinal leak location was confirmed and repaired during surgery. The result was considered as accurate when cerebrospinal leak was absent after surgery. According to the surgical exploration, the preoperative diagnosis of the active cerebrospinal leak location was accurate in 9 out of 12 patients with CT scan. The location could not be confirmed by CT because of multiple fractures in 2 patients and the missed diagnosis occurred in 1 patient. The preoperative diagnosis was accurate in 10 out of 11 patients with MRI examination. MRI cisternography is more advanced than multi-row CT scan in multiple basilar skull fracture. The combination of the two examinations may increase the diagnostic ratio of active cerebrospinal leak

Optical RAM row access using WDM-enabled all-passive row/column decoders

Science.gov (United States)

Papaioannou, Sotirios; Alexoudi, Theoni; Kanellos, George T.; Miliou, Amalia; Pleros, Nikos

2014-03-01

Towards achieving a functional RAM organization that reaps the advantages offered by optical technology, a complete set of optical peripheral modules, namely the Row (RD) and Column Decoder (CD) units, is required. In this perspective, we demonstrate an all-passive 2×4 optical RAM RD with row access operation and subsequent all-passive column decoding to control the access of WDM-formatted words in optical RAM rows. The 2×4 RD exploits a WDM-formatted 2-bit-long memory WordLine address along with its complementary value, all of them encoded on four different wavelengths and broadcasted to all RAM rows. The RD relies on an all-passive wavelength-selective filtering matrix (λ-matrix) that ensures a logical `0' output only at the selected RAM row. Subsequently, the RD output of each row drives the respective SOA-MZI-based Row Access Gate (AG) to grant/block the entry of the incoming data words to the whole memory row. In case of a selected row, the data word exits the row AG and enters the respective CD that relies on an allpassive wavelength-selective Arrayed Waveguide Grating (AWG) for decoding the word bits into their individual columns. Both RD and CD procedures are carried out without requiring any active devices, assuming that the memory address and data word bits as well as their inverted values will be available in their optical form by the CPU interface. Proof-of-concept experimental verification exploiting cascaded pairs of AWGs as the λ-matrix is demonstrated at 10Gb/s, providing error-free operation with a peak power penalty lower than 0.2dB for all optical word channels.

Maximum-intensity-projection CT angiography for evaluating head and neck tumors. Usefulness of helical CT and auto bone masking method

International Nuclear Information System (INIS)

Sakai, Osamu; Nakashima, Noriko; Ogawa, Chiaki; Shen, Yun; Takata, Yasunori; Azemoto, Shougo.

1994-01-01

Angiographic images of 10 adult patients with head and neck tumors were obtained by helical computed tomography (CT) using maximum intensity projection (MIP). In all cases, the vasculature of the head and neck region was directly demonstrated. In the head and neck, bone masking is a more important problem than in other regions. We developed an effective automatic bone masking method (ABM) using 2D/3D connectivity. Helical CT angiography with MIP and ABM provided accurate anatomic depiction, and was considered to be helpful in preoperative evaluation of head and neck tumors. (author)

High-Resolution CT and Angiographic Evaluation of NexStent Wall Adaptation

International Nuclear Information System (INIS)

Nemes, Balazs; Lukacs, Levente; Balazs, Gyoergy; Dosa, Edit; Berczi, Viktor; Huettl, Kalman

2009-01-01

Carotid stenting is a minimally invasive treatment for extracranial carotid artery stenosis. Stent design may affect technical success and complications in a certain subgroup of patients. We examined the wall adaptability of a new closed-cell carotid stent (NexStent), which has a unique rolled sheet design. Forty-one patients had 42 carotid arteries treated with angioplasty and stenting for internal carotid artery stenosis. The mean patient age was 65 ± 10 years. All patients underwent high-resolution computed tomographic angiography after the stent implantation. Data analysis included pre- and postprocedural stenosis, procedure complications, plaque calcification, and stent apposition. We reviewed the angiographic and computed tomographic images for plaque coverage and stent expansion. All procedures were technically successful. Mean stenosis was reduced from 84 ± 8% before the procedure to 15.7 ± 7% after stenting. Two patients experienced transient ischemic attack; one patient had bradycardia and hypotension. Stent induced kinking was observed in one case. Good plaque coverage and proper overlapping of the rolled sheet was achieved in all cases. There was weak correlation between the residual stenosis and the amount of calcification. The stent provides adequate expansion and adaptation to the tapering anatomy of the bifurcation.

The usefulness of the adaptive dose shield for the infant CT

International Nuclear Information System (INIS)

Kojima, Hideyuki; Tsujimura, Asuka; Yabe, Hitoshi

2011-01-01

The spiral scan with a wide detector row such as the 64-detector row computed tomography (CT) system may increase radiation exposure for infants because the irradiation range is wider than the planned range. The adaptive dose shield (ADS) prevents radiation exposure greater than the planned range. We examined the usefulness of the protection effect of the ADS for the infant inner ear CT. To confirm the protection effect of the ADS, we scanned X-ray films by using the 64-detector row CT system and measured the difference of the planned range and the irradiation range. The result of that is that when the planned range was small, the protection effect for the scan ending side was inferior to the scan starting side. And also, when the gantry rotation speed and pitch factor (PF) were high values, the protection effect was inferior to a low gantry rotation speed and low PF. There was a combination of gantry rotation speed and PF at which the protection effect decreases. Due to changes of the scanning direction and PF for the infant inner ear, the crystalline lens radiation exposure dose decreased from 11.89 mGy to 4.37 mGy. In conclusion, the ADS can reduce the radiation exposure dose of an adjacent organ. Therefore, it was thought that the ADS was a useful radiation exposure reduction function for infants in the 64-detector row CT system. (author)

Technical Note: Evaluation of a 160-mm/256-row CT scanner for whole-heart quantitative myocardial perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

So, Aaron, E-mail: aso@robarts.ca [Imaging Program, Lawson Health Research Institute, London, Ontario N6A 4V2 (Canada); Imai, Yasuhiro; Nett, Brian; Jackson, John; Nett, Liz; Hsieh, Jiang [CT Engineering, GE Healthcare, Waukesha, Wisconsin 53188 (United States); Wisenberg, Gerald; Teefy, Patrick; Yadegari, Andrew [Cardiology, University Hospital, London Health Sciences Centre, London, Ontario N6A 5A5 (Canada); Islam, Ali [Radiology, St. Joseph’s Hospital London, Ontario N6A 4V2 (Canada); Lee, Ting-Yim [Imaging Program, Lawson Health Research Institute, London, Ontario N6A 4V2, Canada and Imaging Research Laboratories, Robarts Research Institute, London, Ontario N6A 5K8 (Canada)

2016-08-15

Purpose: The authors investigated the performance of a recently introduced 160-mm/256-row CT system for low dose quantitative myocardial perfusion (MP) imaging of the whole heart. This platform is equipped with a gantry capable of rotating at 280 ms per full cycle, a second generation of adaptive statistical iterative reconstruction (ASiR-V) to correct for image noise arising from low tube voltage potential/tube current dynamic scanning, and image reconstruction algorithms to tackle beam-hardening, cone-beam, and partial-scan effects. Methods: Phantom studies were performed to investigate the effectiveness of image noise and artifact reduction with a GE Healthcare Revolution CT system for three acquisition protocols used in quantitative CT MP imaging: 100, 120, and 140 kVp/25 mAs. The heart chambers of an anthropomorphic chest phantom were filled with iodinated contrast solution at different concentrations (contrast levels) to simulate the circulation of contrast through the heart in quantitative CT MP imaging. To evaluate beam-hardening correction, the phantom was scanned at each contrast level to measure the changes in CT number (in Hounsfield unit or HU) in the water-filled region surrounding the heart chambers with respect to baseline. To evaluate cone-beam artifact correction, differences in mean water HU between the central and peripheral slices were compared. Partial-scan artifact correction was evaluated from the fluctuation of mean water HU in successive partial scans. To evaluate image noise reduction, a small hollow region adjacent to the heart chambers was filled with diluted contrast, and contrast-to-noise ratio in the region before and after noise correction with ASiR-V was compared. The quality of MP maps acquired with the CT system was also evaluated in porcine CT MP studies. Myocardial infarct was induced in a farm pig from a transient occlusion of the distal left anterior descending (LAD) artery with a catheter-based interventional procedure. MP

Technical Note: Evaluation of a 160-mm/256-row CT scanner for whole-heart quantitative myocardial perfusion imaging

International Nuclear Information System (INIS)

So, Aaron; Imai, Yasuhiro; Nett, Brian; Jackson, John; Nett, Liz; Hsieh, Jiang; Wisenberg, Gerald; Teefy, Patrick; Yadegari, Andrew; Islam, Ali; Lee, Ting-Yim

2016-01-01

Purpose: The authors investigated the performance of a recently introduced 160-mm/256-row CT system for low dose quantitative myocardial perfusion (MP) imaging of the whole heart. This platform is equipped with a gantry capable of rotating at 280 ms per full cycle, a second generation of adaptive statistical iterative reconstruction (ASiR-V) to correct for image noise arising from low tube voltage potential/tube current dynamic scanning, and image reconstruction algorithms to tackle beam-hardening, cone-beam, and partial-scan effects. Methods: Phantom studies were performed to investigate the effectiveness of image noise and artifact reduction with a GE Healthcare Revolution CT system for three acquisition protocols used in quantitative CT MP imaging: 100, 120, and 140 kVp/25 mAs. The heart chambers of an anthropomorphic chest phantom were filled with iodinated contrast solution at different concentrations (contrast levels) to simulate the circulation of contrast through the heart in quantitative CT MP imaging. To evaluate beam-hardening correction, the phantom was scanned at each contrast level to measure the changes in CT number (in Hounsfield unit or HU) in the water-filled region surrounding the heart chambers with respect to baseline. To evaluate cone-beam artifact correction, differences in mean water HU between the central and peripheral slices were compared. Partial-scan artifact correction was evaluated from the fluctuation of mean water HU in successive partial scans. To evaluate image noise reduction, a small hollow region adjacent to the heart chambers was filled with diluted contrast, and contrast-to-noise ratio in the region before and after noise correction with ASiR-V was compared. The quality of MP maps acquired with the CT system was also evaluated in porcine CT MP studies. Myocardial infarct was induced in a farm pig from a transient occlusion of the distal left anterior descending (LAD) artery with a catheter-based interventional procedure. MP

Technical Note: Evaluation of a 160-mm/256-row CT scanner for whole-heart quantitative myocardial perfusion imaging.

Science.gov (United States)

So, Aaron; Imai, Yasuhiro; Nett, Brian; Jackson, John; Nett, Liz; Hsieh, Jiang; Wisenberg, Gerald; Teefy, Patrick; Yadegari, Andrew; Islam, Ali; Lee, Ting-Yim

2016-08-01

The authors investigated the performance of a recently introduced 160-mm/256-row CT system for low dose quantitative myocardial perfusion (MP) imaging of the whole heart. This platform is equipped with a gantry capable of rotating at 280 ms per full cycle, a second generation of adaptive statistical iterative reconstruction (ASiR-V) to correct for image noise arising from low tube voltage potential/tube current dynamic scanning, and image reconstruction algorithms to tackle beam-hardening, cone-beam, and partial-scan effects. Phantom studies were performed to investigate the effectiveness of image noise and artifact reduction with a GE Healthcare Revolution CT system for three acquisition protocols used in quantitative CT MP imaging: 100, 120, and 140 kVp/25 mAs. The heart chambers of an anthropomorphic chest phantom were filled with iodinated contrast solution at different concentrations (contrast levels) to simulate the circulation of contrast through the heart in quantitative CT MP imaging. To evaluate beam-hardening correction, the phantom was scanned at each contrast level to measure the changes in CT number (in Hounsfield unit or HU) in the water-filled region surrounding the heart chambers with respect to baseline. To evaluate cone-beam artifact correction, differences in mean water HU between the central and peripheral slices were compared. Partial-scan artifact correction was evaluated from the fluctuation of mean water HU in successive partial scans. To evaluate image noise reduction, a small hollow region adjacent to the heart chambers was filled with diluted contrast, and contrast-to-noise ratio in the region before and after noise correction with ASiR-V was compared. The quality of MP maps acquired with the CT system was also evaluated in porcine CT MP studies. Myocardial infarct was induced in a farm pig from a transient occlusion of the distal left anterior descending (LAD) artery with a catheter-based interventional procedure. MP maps were generated

CT of the musculoskeletal system: What is left is the days of MRI?

International Nuclear Information System (INIS)

West, A.T.H.; Marshall, T.J.; Bearcroft, P.W.

2009-01-01

Magnetic resonance imaging (MRI) plays a central role in the modern imaging of musculoskeletal disorders, due to its ability to produce multiplanar images and characterise soft tissues accurately. However, computed tomography (CT) still has an important role to play, not merely as an alternative to MRI, but as being the preferred imaging investigation in some situations. This article briefly reviews the history of CT technology, the technical factors involved and a number of current applications, as well as looking at future areas where CT may be employed. The advent of ever-increasing numbers of rows of detectors has opened up more possible uses for CT technology. However, diagnostic images may be obtained from CT systems with four rows of detectors or more, and their ability to produce near isotropic voxels and therefore multiplanar reformats. (orig.)

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)

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.)

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.)

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.)

Single-row versus double-row repair of the distal Achilles tendon: a biomechanical comparison.

Science.gov (United States)

Pilson, Holly; Brown, Philip; Stitzel, Joel; Scott, Aaron

2012-01-01

Surgery for recalcitrant insertional Achilles tendinopathy often consists of partial or total release of the insertion site, debridement of the diseased portion of the tendon, calcaneal ostectomy, and reattachment of the Achilles to the calcaneus. Although single-row and double-row techniques exist for repair of the detached Achilles tendon, biomechanical data are lacking to support one technique over the other. Based on data extrapolated from the study of rotator cuff repairs, we hypothesized that a double-row construct would provide superior fixation strength over a single-row repair. Eighteen human cadaveric Achilles tendons (9 matched pairs) with attached calcanei were repaired with single-row or double-row techniques. Specimens were mounted in a servohydraulic materials testing machine, subjected to a preconditioning cycle, and loaded to failure. Failure was defined as suture breakage or pullout, midsubstance tendon rupture, or anchor pullout. Among the failures were 12 suture failures, 5 proximal-row anchor failures, and 1 distal-row anchor failure. No midsubstance tendon ruptures or testing apparatus failures were observed. There were no statistically significant differences in the peak load to failure between the single-row and double-row repairs (p = .46). Similarly, no significant differences were observed with regards to mean energy expenditure to failure (p = .069). The present study demonstrated no biomechanical advantages of the double-row repair over a single-row repair. Despite the lack of a clear biomechanical advantage, there may exist clinical advantages of a double-row repair, such as reduction in knot prominence and restoration of the Achilles footprint. Copyright © 2012 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

A simple method for 3D lesion reconstruction from two projected angiographic images: implementation to a stereotactic radiotherapy treatment planning system

International Nuclear Information System (INIS)

Theodorou, K.; Kappas, C.; Gaboriaud, G.; Mazal, A.D.; Petrascu, O.; Rosenwald, J.C.

1997-01-01

Introduction: The most used imaging modality for diagnosis and localisation of arteriovenous malformations (AVMs) treated with stereotactic radiotherapy is angiography. The fact that the angiographic images are projected images imposes the need of the 3D reconstruction of the lesion. This, together with the 3D head anatomy from CT images could provide all the necessary information for stereotactic treatment planning. We have developed a method to combine the complementary information provided by angiography and 2D computerized tomography, matching the reconstructed AVM structure with the reconstructed head of the patient. Materials and methods: The ISIS treatment planning system, developed at Institute Curie, has been used for image acquisition, stereotactic localisation and 3D visualisation. A series of CT slices are introduced in the system as well as two orthogonal angiographic projected images of the lesion. A simple computer program has been developed for the 3D reconstruction of the lesion and for the superposition of the target contour on the CT slices of the head. Results and conclusions: In our approach we consider that the reconstruction can be made if the AVM is approximated with a number of adjacent ellipses. We assessed the method comparing the values of the reconstructed and the actual volumes of the target using linear regression analysis. For treatment planning purposes we overlapped the reconstructed AVM on the CT slices of the head. The above feature is to our knowledge a feature that the majority of the commercial stereotactic radiotherapy treatment planning system could not provide. The implementation of the method into ISIS TPS shows that we can reliably approximate and visualize the target volume

Comparison between single-row and double-row rotator cuff repair: a biomechanical study.

Science.gov (United States)

Milano, Giuseppe; Grasso, Andrea; Zarelli, Donatella; Deriu, Laura; Cillo, Mario; Fabbriciani, Carlo

2008-01-01

The aim of this study was to compare the mechanical behavior under cyclic loading test of single-row and double-row rotator cuff repair with suture anchors in an ex-vivo animal model. For the present study, 50 fresh porcine shoulders were used. On each shoulder, a crescent-shaped full-thickness tear of the infraspinatus was performed. Width of the tendon tear was 2 cm. The lesion was repaired using metal suture anchors. Shoulders were divided in four groups, according the type of repair: single-row tension-free repair (Group 1); single-row tension repair (Group 2); double-row tension-free repair (Group 3); double-row tension repair (Group 4); and a control group. Specimens were subjected to a cyclic loading test. Number of cycles at 5 mm of elongation and at failure, and total elongation were calculated. Single-row tension repair showed significantly poorest results for all the variables considered, when compared with the other groups. Regarding the mean number of cycles at 5 mm of elongation and at failure, there was a nonsignificant difference between Groups 3 and 4, and both of them were significantly greater than Group 1. For mean total elongation, the difference between Groups 1, 3, and 4 was not significant, but all of them were significantly lower than the control group. A single-row repair is particularly weak when performed under tension. Double-row repair is significantly more resistant to cyclic displacement than single-row repair in both tension-free and tension repair. Double-row repair technique can be primarily considered for large, unstable rotator cuff tears to improve mechanical strength of primary fixation of tendons to bone.

Hyperdense middle cerebral artery CT sign

International Nuclear Information System (INIS)

Bastianello, S.; Pierallini, A.; Colonnese, C.; Brughitta, G.; Angeloni, U.; Antonelli, M.; Fantozzi, L.M.; Fieschi, C.; Bozzao, L.

1991-01-01

The early CT finding of an hyperdensity of a portion of the middle cerebral artery Hyperdense Middle Cerebral Artery Sign (HMCAS), in patients with supratentorial stroke, is often indicative of an embolic occlusion. Aim of this study was to verify the incidence and reliability of the HMCAS and its possible correlation with early CT findings and with the extent of late brain damage. We studied 36 patients presenting with symptoms of stroke in the MCA territory, by means of CT and angiography performed respectively within 4 and 6 hours. Follow-up CT scans were then obtained after one week and three months from the ischemic event. The HMCAS was present in 50% of our patients and in this group it always correlated positively with the angiographic finding of occlusion. The same group presented a high incidence of early CT hypodensity (88%). Finally the presence of HMCAS might be considered a negative prognostic sign for the development of extensive brain damage. (orig.)

The cost-effectiveness of single-row compared with double-row arthroscopic rotator cuff repair.

Science.gov (United States)

Genuario, James W; Donegan, Ryan P; Hamman, Daniel; Bell, John-Erik; Boublik, Martin; Schlegel, Theodore; Tosteson, Anna N A

2012-08-01

Interest in double-row techniques for arthroscopic rotator cuff repair has increased over the last several years, presumably because of a combination of literature demonstrating superior biomechanical characteristics and recent improvements in instrumentation and technique. As a result of the increasing focus on value-based health-care delivery, orthopaedic surgeons must understand the cost implications of this practice. The purpose of this study was to examine the cost-effectiveness of double-row arthroscopic rotator cuff repair compared with traditional single-row repair. A decision-analytic model was constructed to assess the cost-effectiveness of double-row arthroscopic rotator cuff repair compared with single-row repair on the basis of the cost per quality-adjusted life year gained. Two cohorts of patients (one with a tear of row compared with single-row arthroscopic rotator cuff repair was $571,500 for rotator cuff tears of row repair was less than $287 for small or moderate tears and less than $352 for large or massive tears compared with the cost of single-row repair, then double-row repair would represent a cost-effective surgical alternative. On the basis of currently available data, double-row rotator cuff repair is not cost-effective for any size rotator cuff tears. However, variability in the values for costs and probability of retear can have a profound effect on the results of the model and may create an environment in which double-row repair becomes the more cost-effective surgical option. The identification of the threshold values in this study may help surgeons to determine the most cost-effective treatment.

CT Angiographic Demonstration of a Mesenteric Vessel 'Whirlpool' in Intestinal Malrotation and Midgut Volvulus: a Case Report

International Nuclear Information System (INIS)

Bozlar, Ugur; Ugurel, Mehmet Sahin; Ustunsoz, Bahri; Coskun, Unsal

2008-01-01

Although the color Doppler ultrasonography diagnosis of intestinal malrotation with midgut volvulus, based on the typical 'whirlpool' appearance of the mesenteric vascular structures is well-defined in the peer-reviewed literature, the combination of both the angiographic illustration of these findings and the contemporary state-of-the-art imaging techniques is lacking. We report the digital subtraction angiography and multidetector computed tomography angiography findings of a 37-year-old male with intestinal malrotation

A comparative clinical evaluation of arthroscopic single-row versus double-row supraspinatus tendon repair.

Science.gov (United States)

Buess, Eduard; Waibl, Bernhard; Vogel, Roger; Seidner, Robert

2009-10-01

Cadaveric studies and commercial pressure have initiated a strong trend towards double-row repair in arthroscopic cuff surgery. The objective of this study was to evaluate if the biomechanical advantages of a double-row supraspinatus tendon repair would result in superior clinical outcome and higher abduction strength. A retrospective study of two groups of 32 single-row and 33 double-row repairs of small to medium cuff tears was performed. The Simple Shoulder Test (SST) and a visual analog scale for pain were used to evaluate the outcome. The participation rate was 100%. A subset of patients was further investigated with the Constant Score (CS) including electronic strength measurement. The double-row repair patients had significantly more (p = 0.01) yes answers in the SST than the single-row group, and pain reduction was slightly better (p = 0.03). No difference was found for the relative CS (p = 0.86) and abduction strength (p = 0.74). Patient satisfaction was 100% for double-row and 97% for single-row repair. Single- and double-row repairs both achieved excellent clinical results. Evidence of superiority of double-row repair is still scarce and has to be balanced against the added complexity of the procedure and higher costs.

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

Influence of a combined CT/C-arm system on periprocedural workflow and procedure times in mechanical thrombectomy

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Pfaff, Johannes; Herweh, Christian; Pham, Mirko; Heiland, Sabine; Bendszus, Martin; Moehlenbruch, Markus Alfred [University of Heidelberg, Department of Neuroradiology, Heidelberg (Germany); Schoenenberger, Silvia; Nagel, Simon; Ringleb, Peter Arthur [University of Heidelberg, Department of Neurology, Heidelberg (Germany)

2017-09-15

To achieve the fastest possible workflow in ischaemic stroke, we developed a CT/C-arm system, which allows imaging and endovascular treatment on the same patient table. This prospective, monocentric trial was conducted between October 2014 and August 2016. Patients received stroke imaging and mechanical thrombectomy under general anaesthesia (GA) or conscious sedation (CS) using our combined setup comprising a CT-scanner and a mobile C-arm X-ray device. Primary endpoint was time between stroke imaging and groin puncture. We compared periprocedural workflow and procedure times with the literature and a matched patient cohort treated with a biplane angiographic system before installation of the CT/C-arm system. In 50 patients with acute ischaemic stroke due to large-vessel occlusion in the anterior circulation, comparable recanalization rates were achieved by using the CT/C-arm setup (TICI2b-3:CT/C-arm-GA: 85.7%; CT/C-arm-CS: 90.9%; Angiosuite: 78.6%; p = 0.269) without increasing periprocedural complications. Elimination of patient transport resulted in a significant reduction of the time between stroke imaging and groin puncture: median, min (IQR): CT/C-arm-GA: 43 (35-52); CT/C-arm-CS: 39 (28-49); Angiosuite: 64 (48-74); p < 0.0001. The combined CT/C-arm system allows comparable recanalization rates as a biplane angiographic system and accelerates the start of the endovascular stroke treatment. (orig.)

Influence of a combined CT/C-arm system on periprocedural workflow and procedure times in mechanical thrombectomy

International Nuclear Information System (INIS)

Pfaff, Johannes; Herweh, Christian; Pham, Mirko; Heiland, Sabine; Bendszus, Martin; Moehlenbruch, Markus Alfred; Schoenenberger, Silvia; Nagel, Simon; Ringleb, Peter Arthur

2017-01-01

To achieve the fastest possible workflow in ischaemic stroke, we developed a CT/C-arm system, which allows imaging and endovascular treatment on the same patient table. This prospective, monocentric trial was conducted between October 2014 and August 2016. Patients received stroke imaging and mechanical thrombectomy under general anaesthesia (GA) or conscious sedation (CS) using our combined setup comprising a CT-scanner and a mobile C-arm X-ray device. Primary endpoint was time between stroke imaging and groin puncture. We compared periprocedural workflow and procedure times with the literature and a matched patient cohort treated with a biplane angiographic system before installation of the CT/C-arm system. In 50 patients with acute ischaemic stroke due to large-vessel occlusion in the anterior circulation, comparable recanalization rates were achieved by using the CT/C-arm setup (TICI2b-3:CT/C-arm-GA: 85.7%; CT/C-arm-CS: 90.9%; Angiosuite: 78.6%; p = 0.269) without increasing periprocedural complications. Elimination of patient transport resulted in a significant reduction of the time between stroke imaging and groin puncture: median, min (IQR): CT/C-arm-GA: 43 (35-52); CT/C-arm-CS: 39 (28-49); Angiosuite: 64 (48-74); p < 0.0001. The combined CT/C-arm system allows comparable recanalization rates as a biplane angiographic system and accelerates the start of the endovascular stroke treatment. (orig.)

Angiographic diagnosis and treatment of gastrointestinal bleeding

International Nuclear Information System (INIS)

Park, Jae Hyung; Sung, Kyu Bo; Koo, Kyung Hoi; Bae, Tae Young; Chung, Eun Chul; Han, Man Chung

1986-01-01

Diagnostic angiographic evaluations were done in 33 patients with gastrointestinal bleeding for recent 5 years at Department of Radiology, Seoul National University Hospital. On 11 patients of them, therapeutic interventional procedures were made and the results were analysed. 1. In a total of 33 cases, there were 18 cases of upper GI bleeding and 15 cases of lower GI bleeding. The most frequent causes were peptic ulcer in the former and intestinal typhoid fever in the latter. 2. Bleeding sites were localized angiographically in 28 cases, so the detection rate was 85%. Four of the five angiographically negative cases were lower GI bleeding cases. 3. The most frequent bleeding site was left gastric artery (7/33). The next was ileocecal branch of superior mesenteric artery (6/33). 4. Among the 11 interventional procedures, Gelfoam embolization was done in 7 cases and Vasopressin infusion was tried in 4 cases. They were successful in 4 and 3 cases, suggesting 57% and 47% success rates respectively.

Angiographic diagnosis and treatment of gastrointestinal bleeding

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Park, Jae Hyung; Sung, Kyu Bo; Koo, Kyung Hoi; Bae, Tae Young; Chung, Eun Chul; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1986-02-15

Diagnostic angiographic evaluations were done in 33 patients with gastrointestinal bleeding for recent 5 years at Department of Radiology, Seoul National University Hospital. On 11 patients of them, therapeutic interventional procedures were made and the results were analysed. 1. In a total of 33 cases, there were 18 cases of upper GI bleeding and 15 cases of lower GI bleeding. The most frequent causes were peptic ulcer in the former and intestinal typhoid fever in the latter. 2. Bleeding sites were localized angiographically in 28 cases, so the detection rate was 85%. Four of the five angiographically negative cases were lower GI bleeding cases. 3. The most frequent bleeding site was left gastric artery (7/33). The next was ileocecal branch of superior mesenteric artery (6/33). 4. Among the 11 interventional procedures, Gelfoam embolization was done in 7 cases and Vasopressin infusion was tried in 4 cases. They were successful in 4 and 3 cases, suggesting 57% and 47% success rates respectively.

Assessment of coronary artery stent patency by electron-beam CT

International Nuclear Information System (INIS)

Knollmann, Friedrich D.; Felix, Roland; Moeller, Joerg; Gebert, Axel; Bethge, Christian

2004-01-01

Following coronary angioplasty and stent implantation, restenosis remains common and its outcome difficult to predict. We set out to determine the diagnostic accuracy of electron-beam computed tomography (EBCT) for the non-invasive detection of stent obstruction. In a prospective, blinded investigation, we included 152 coronary artery segments in 117 patients treated with a stent implant. All segments were evaluated by a dynamic EBCT study that depicted contrast bolus passage distal to the stent and a CT angiographic study of the entire coronary arteries. It was found that delayed contrast enhancement in the distal segment correlated with angiographic stent obstruction (Spearman's rank correlation, P=0.008), while all other indicators of stent occlusion did not correlate with angiographic diagnosis. However, direct comparison of patients with obstruction of less vs. more than 75% of luminal diameter did not yield any statistically significant differences of distal enhancement delay, and for the detection of >90% occlusion, the sensitivity was 72% at a specificity of 60%. Although delayed contrast enhancement distal to the stent upon EBCT did correlate with angiographical obstruction, the correlation did not suffice to appear clinically satisfactory. (orig.)

Assessment of coronary artery stent patency by electron-beam CT

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Knollmann, Friedrich D.; Felix, Roland [Department of Radiology, Charite, Campus Virchow-Klinikum, Humboldt-University, Augustenburger Platz 1, 13353, Berlin (Germany); Moeller, Joerg; Gebert, Axel; Bethge, Christian [Department of Cardiology, Juedisches Krankenhaus, Berlin (Germany)

2004-08-01

Following coronary angioplasty and stent implantation, restenosis remains common and its outcome difficult to predict. We set out to determine the diagnostic accuracy of electron-beam computed tomography (EBCT) for the non-invasive detection of stent obstruction. In a prospective, blinded investigation, we included 152 coronary artery segments in 117 patients treated with a stent implant. All segments were evaluated by a dynamic EBCT study that depicted contrast bolus passage distal to the stent and a CT angiographic study of the entire coronary arteries. It was found that delayed contrast enhancement in the distal segment correlated with angiographic stent obstruction (Spearman's rank correlation, P=0.008), while all other indicators of stent occlusion did not correlate with angiographic diagnosis. However, direct comparison of patients with obstruction of less vs. more than 75% of luminal diameter did not yield any statistically significant differences of distal enhancement delay, and for the detection of >90% occlusion, the sensitivity was 72% at a specificity of 60%. Although delayed contrast enhancement distal to the stent upon EBCT did correlate with angiographical obstruction, the correlation did not suffice to appear clinically satisfactory. (orig.)

Cerebral cavernous angioma. 16 cases. Aspects in CT and MR

International Nuclear Information System (INIS)

Pina, J.I.; Medrano, J.; Lasierra, R.; Benito, J.L. de; Feijoo, R.; Fernandez, J.A.; Villavieja, J.L.

1995-01-01

The cerebral cavernous angioma (CA) is included in the group of cerebral malformations that can not be detected angiographically. We present the retrospective study of 16 patients, diagnosed as having CA, comparing the data provided by CT and MR, as well as the contribution of cerebral angiography. (Author) 25 refs

Detection of coronary calcification in ultrafast CT compared to coronary angiography

International Nuclear Information System (INIS)

Koesling, S.; Hoffmann, U.; Rother, T.; Lieberenz, S.; Heywang-Koebrunner, S.H.; Schulz, H.G.

1994-01-01

The angiographical findings of 24 patients with coronary artery disease were compared with qualitative and quantitative detection of coronary calcification by ultrafast CT. Doubts concerning the capabilities of the ultrafast CT for a screening of coronary artery disease arise when the results of one third false positive and fase negative findings are considered. Variations in the quantification of coronary calcification were too great to allow a realistic assessment of the degree of stenosis of the coronary arteries. (orig.) [de

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.)

Physics and basic technology of CT

International Nuclear Information System (INIS)

Mahesh, Mahadevappa

2017-01-01

Computed Tomography is one of the prime imaging modalities in any hospital around the globe. From its inception in 1973, CT technology have advanced leaps and bounds in medical diagnosis. Advances in X-ray tubes, detection technologies and image reconstruction methods led to the development of multiple-row detector CT (MDCT) technologies in early 2000, that has been the impetus for new fields such as Cardiovascular CT, Hybrid CT (PET-CT and SPECT-CT), CT Perfusion, Cone Beam CT, etc. It is now possible to image the entire organ (such as heart) in less than 0.3 seconds providing isotropic resolution images with high temporal resolution. With all X-ray imaging modalities, including CT, the concern is the radiation dose. Since CT procedures are one of the major imaging procedures performed in any hospital, it is important to optimize CT protocols in order to provide quality images at optimal radiation dose

Coronary angiographic characteristics that influence fractional flow reserve.

Science.gov (United States)

Natsumeda, Makoto; Nakazawa, Gaku; Murakami, Tsutomu; Torii, Sho; Ijichi, Takeshi; Ohno, Yohei; Masuda, Naoki; Shinozaki, Norihiko; Ogata, Nobuhiko; Yoshimachi, Fuminobu; Ikari, Yuji

2015-01-01

Percutaneous coronary intervention (PCI) guided with fractional flow reserve (FFR) has been shown to improve clinical outcome. Although coronary angiography is the standard method for PCI guidance, the visual severity of stenosis is not always correlated with functional severity, suggesting that there are additional angiographic factors that affect functional ischemia. To evaluate angiographic predictors of positive FFR in stenotic lesions, angiographic characteristics of 260 consecutive patients (362 lesions) who underwent FFR testing from April 2009 to September 2012 were analyzed. A scoring system (STABLED score) using these predictors was developed and compared with quantitative coronary angiography (QCA). %Diameter stenosis >50% (OR, 8.43; P20 mm (OR, 5.40; P=0.0002), and distance from ostium <20 mm (OR, 1.94; P=0.028) were determined as independent predictors of positive FFR. Area under the ROC curve for probability of positive FFR using the STABLED score (Stenosis 2 points, TAndem lesion 1 point, Bifurcation 1 point, LEsion length 1 point, Distance from ostium 1 point) was 0.85, higher than that for QCA stenosis alone (0.76). STABLED score ≥3 had 72.3% sensitivity and 83.6% specificity for predicting positive FFR, and PPV was 76.7%. Specific angiographic features are applicable for predicting functional ischemia. STABLED score correlates well with FFR.

Row fault detection system

Science.gov (United States)

Archer, Charles Jens [Rochester, MN; Pinnow, Kurt Walter [Rochester, MN; Ratterman, Joseph D [Rochester, MN; Smith, Brian Edward [Rochester, MN

2008-10-14

An apparatus, program product and method checks for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

Economic evaluation of angiographic interventions including a whole-radiology in- and outpatient care; Wirtschaftliche Evaluation angiographischer Interventionen einschliesslich einer radiologischen stationaeren und ambulanten Patientenbetreuung

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Nolte-Ernsting, C.; Abel, K.; Krupski, G.; Lorenzen, J.; Adam, G. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Hamburg-Eppendorf (Germany)

2006-01-01

Purpose: To determine the economic efficiency of a whole-radiology in- and outpatient treatment with angiographic interventions performed as the main or sole therapy. Materials and Methods: The calculations represent the data of a university radiology department, including the following angiographic interventions (neuroradiology not considered): Vascular intervention (PTA, stent implantation) of kidneys and extremities, recanalization of hemodialysis access, chemoembolization, diagnostic arterioportal liver CT, port implantation, varicocele embolization, PTCD, percutaneous implantation of biliary stent. First, the different angiographic interventions are categorized with reference to the German DRG system 2005. Considering the example of a university hospital, the individual cost of each intervention is calculated and correlated with reimbursements by G-DRG2005 and so-called ''ambulant operation'' (EBM200plus). With these data, profits and losses are calculated for both in- and outpatient care. Results: Radiologic interventions of inpatients yield a profit in the majority of cases. With a base rate of 2900 Euro, the profits in our university hospital range between -872 Euro and +3411 Euro (mean: +1348 Euro). On the other hand, those angiographic interventions suitable for ''ambulant operation'' generate average profits of +372 Euro, if only direct costs are considered. The data of outpatient radiological interventions average between 381 Euro up to 1612 Euro lower than compared with profits obtained from in patient care. (orig.)

Outcomes of single-row and double-row arthroscopic rotator cuff repair: a systematic review.

Science.gov (United States)

Saridakis, Paul; Jones, Grant

2010-03-01

Arthroscopic rotator cuff repair is a common procedure that is gaining wide acceptance among orthopaedic surgeons because it is less invasive than open repair techniques. However, there is little consensus on whether to employ single-row or double-row fixation. The purpose of the present study was to systematically review the English-language literature to see if there is a difference between single-row and double-row fixation techniques in terms of clinical outcomes and radiographic healing. PubMed, the Cochrane Central Register of Controlled Trials, and EMBASE were reviewed with the terms "arthroscopic rotator cuff," "single row repair," and "double row repair." The inclusion criteria were a level of evidence of III (or better), an in vivo human clinical study on arthroscopic rotator cuff repair, and direct comparison of single-row and double-row fixation. Excluded were technique reports, review articles, biomechanical studies, and studies with no direct comparison of arthroscopic rotator cuff repair techniques. On the basis of these criteria, ten articles were found, and a review of the full-text articles identified six articles for final review. Data regarding demographic characteristics, rotator cuff pathology, surgical techniques, biases, sample sizes, postoperative rehabilitation regimens, American Shoulder and Elbow Surgeons scores, University of California at Los Angeles scores, Constant scores, and the prevalence of recurrent defects noted on radiographic studies were extracted. Confidence intervals were then calculated for the American Shoulder and Elbow Surgeons, University of California at Los Angeles, and Constant scores. Quality appraisal was performed by the two authors to identify biases. There was no significant difference between the single-row and double-row groups within each study in terms of postoperative clinical outcomes. However, one study divided each of the groups into patients with small-to-medium tears ( or = 3 cm in length), and the

CT and MR angiographic findings in dissection of cervical vessels

International Nuclear Information System (INIS)

Link, J.; Brinkmann, G.; Heuser, K.; Heller, M.

1996-01-01

Purpose: To determine the usefulness of CT angiography (CTA) and MR angiography (MRA) for evaluation of dissection in cervical vessels. Material and methods: Dissection of cervical vessels was revealed by conventional angiography in 4 patients (two female, two male) of 30-62 years of age. Dissection was located in the carotid artery (n=3) and in the vertebral artery (n=1). In two patients CTA and in two patients MRA was performed. Results: Diagnosis of dissection was possible by CTA (internal carotid artery: n=2) and by MRA (internal carotid artery and vertebral artery). Imaging of the dissection membrane of the vessel wall was possible in one case with MRA. Conclusion: CT and MR angiography was successful for detection of typical morphology of dissection in all cases. If results in a greater number can be obtained it seems to be conceivable that both methods can be used in primary diagnosis. (orig.) [de

Biomechanical evaluation of a single-row versus double-row repair for complete subscapularis tears.

Science.gov (United States)

Wellmann, Mathias; Wiebringhaus, Philipp; Lodde, Ina; Waizy, Hazibullah; Becher, Christoph; Raschke, Michael J; Petersen, Wolf

2009-12-01

The purpose of the study was to compare a single-row repair and a double-row repair technique for the specific characteristics of a complete subscapularis lesion. Ten pairs of human cadaveric shoulder human shoulder specimens were tested for stiffness and ultimate tensile strength of the intact tendons in a load to failure protocol. After a complete subscapularis tear was provoked, the specimens were assigned to two treatment groups: single-row repair (1) and a double-row repair using a "suture bridge" technique (2). After repair cyclic loading a subsequent load to failure protocol was performed to determine the ultimate tensile load, the stiffness and the elongation behaviour of the reconstructions. The intact subscapularis tendons had a mean stiffness of 115 N/mm and a mean ultimate load of 720 N. The predominant failure mode of the intact tendons was a tear at the humeral insertion site (65%). The double-row technique restored 48% of the ultimate load of the intact tendons (332 N), while the single-row technique revealed a significantly lower ultimate load of 244 N (P = 0.001). In terms of the stiffness, the double-row technique showed a mean stiffness of 81 N/mm which is significantly higher compared to the stiffness of the single-row repairs of 55 N/mm (P = 0.001). The double-row technique has been shown to be stronger and stiffer when compared to a conventional single-row repair. Therefore, this technique is recommended from a biomechanical point of view irrespectively if performed by an open or arthroscopic approach.

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

Biomechanical evaluation of arthroscopic rotator cuff repairs: double-row compared with single-row fixation.

Science.gov (United States)

Ma, C Benjamin; Comerford, Lyn; Wilson, Joseph; Puttlitz, Christian M

2006-02-01

Recent studies have shown that arthroscopic rotator cuff repairs can have higher rates of failure than do open repairs. Current methods of rotator cuff repair have been limited to single-row fixation of simple and horizontal stitches, which is very different from open repairs. The objective of this study was to compare the initial cyclic loading and load-to-failure properties of double-row fixation with those of three commonly used single-row techniques. Ten paired human supraspinatus tendons were split in half, yielding four tendons per cadaver. The bone mineral content at the greater tuberosity was assessed. Four stitch configurations (two-simple, massive cuff, arthroscopic Mason-Allen, and double-row fixation) were randomized and tested on each set of tendons. Specimens were cyclically loaded between 5 and 100 N at 0.25 Hz for fifty cycles and then loaded to failure under displacement control at 1 mm/sec. Conditioning elongation, peak-to-peak elongation, ultimate tensile load, and stiffness were measured with use of a three-dimensional tracking system and compared, and the failure type (suture or anchor pull-out) was recorded. No significant differences were found among the stitches with respect to conditioning elongation. The mean peak-to-peak elongation (and standard error of the mean) was significantly lower for the massive cuff (1.1 +/- 0.1 mm) and double-row stitches (1.1 +/- 0.1 mm) than for the arthroscopic Mason-Allen stitch (1.5 +/- 0.2 mm) (p row fixation (287 +/- 24 N) than for all of the single-row fixations (p row fixation had a significantly higher ultimate tensile load than the three types of single-row fixation stitches. Of the single-row fixations, the massive cuff stitch had cyclic and load-to-failure characteristics similar to the double-row fixation. Anterior repairs of the supraspinatus tendon had significantly stronger biomechanical behavior than posterior repairs.

Angiographically occult vascular malformation of the brain: MR imaging at 1.5 T

International Nuclear Information System (INIS)

Patel, S.C.; Sanders, W.P.; Fuentes, J.; Haggar, A.M.; Mehta, B.A.; Boulos, R.S.; Froelich, J.W.

1986-01-01

MR imaging was performed in nine patients with 12 angiographically occult arteriovenous malformations using a 1.5-T superconducting magnet; four additional patients were imaged using a 0.3-T system. All images were reviewed in conjunction with CT scans. The following observations were made. (1) Eleven of 14 supratentorial lesions were located at the junction of gray and white matter. (2) Exclusing acute hemorrhage, only two lesions displayed mild mass effect. (3) All lesions displayed central foci of high signal intensity, probably representing subacute hemorrhage. (4) All lesions but one showed a peripheral rim of low signal intensity which progressively lost signal with increasing T2 weighting. This most likely represents iron-containing hemosiderin deposition. (5) Lesions were best demonstrated with long repetition times and moderate T2 weighting (TR = 2,500 msec, TE = 25-100 msec). (6) All lesions but one were hyperdense on non-contrast-enhanced CT, although only three had unequivocal calcification. The possibility of hyperdensity due to blood or iron deposition is discussed

Vascular imaging with spiral CT. The way to CY angiography

International Nuclear Information System (INIS)

Prokop, M.; Schaefer, C.; Kalender, W.A.; Polacin, A.; Galanski, M.

1993-01-01

Spiral CT is a technique that allows for high-quality two-dimensional angiographic projections and 3D imaging of vascular structures. The authors present the technical and methodological principles of the technique, including scan parameters and parameters of contrast application for various clinical imaging tasks. They present their experience with over 150 clinical cases using spiral CT angiography. Suitable applications of this technique include cogenital anomalies, aneurysms, dissections, stenoses, thrombi and vascular tumor involvement. Given a problem-adapted examination technique, pathologic changes in vessels of as little as 2 mm can be visualized. In some cases with complex vascular anatomy, spiral CT angiography can be superior to arterial angiography. (orig.) [de

Noninvasive Coronary Angiography using 64-Detector-Row Computed Tomography in Patients with a Low to Moderate Pretest Probability of Significant Coronary Artery Disease

International Nuclear Information System (INIS)

Schlosser, T.; Mohrs, O.K.; Magedanz, A.; Nowak, B.; Voigtlaender, T.; Barkhausen, J.; Schmermund, A.

2007-01-01

Purpose: To evaluate the value of 64-detector-row computed tomography for ruling out high-grade coronary stenoses in patients with a low to moderate pretest probability of significant coronary artery disease. Material and Methods: The study included 61 patients with a suspicion of coronary artery disease on the basis of atypical angina or ambiguous findings in noninvasive stress testing and a class II indication for invasive coronary angiography (ICA). All patients were examined by 64-detector-row computed tomography angiography (CTA) and ICA. On a coronary segmental level, the presence of significant (>50% diameter) stenoses was examined. Results: In a total of 915 segments, CTA detected 62 significant stenoses. Thirty-four significant stenoses were confirmed by ICA, whereas 28 stenoses could not be confirmed by ICA. Twenty-two of them showed wall irregularities on ICA, and six were angiographically normal. Accordingly, on a coronary segmental basis, 28 false-positive and 0 false-negative findings resulted in a sensitivity of 100%, a specificity of 96.8%, a positive predictive value of 54.8%, and a negative predictive value of 100%. The diagnostic accuracy was 96.9%. Conclusion: Sixty-four-detector-row computed tomography reliably detects significant coronary stenoses in patients with suspected coronary artery disease and appears to be helpful in the selection of patients who need to undergo ICA. Calcified and non-calcified plaques are detected. Grading of stenoses in areas with calcification is difficult. Frequently, stenosis severity is overestimated by 64-detector-row computed tomography

Noninvasive Coronary Angiography using 64-Detector-Row Computed Tomography in Patients with a Low to Moderate Pretest Probability of Significant Coronary Artery Disease

Energy Technology Data Exchange (ETDEWEB)

Schlosser, T.; Mohrs, O.K.; Magedanz, A.; Nowak, B.; Voigtlaender, T.; Barkhausen, J.; Schmermund, A. [Dept. of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen (Germany)

2007-04-15

Purpose: To evaluate the value of 64-detector-row computed tomography for ruling out high-grade coronary stenoses in patients with a low to moderate pretest probability of significant coronary artery disease. Material and Methods: The study included 61 patients with a suspicion of coronary artery disease on the basis of atypical angina or ambiguous findings in noninvasive stress testing and a class II indication for invasive coronary angiography (ICA). All patients were examined by 64-detector-row computed tomography angiography (CTA) and ICA. On a coronary segmental level, the presence of significant (>50% diameter) stenoses was examined. Results: In a total of 915 segments, CTA detected 62 significant stenoses. Thirty-four significant stenoses were confirmed by ICA, whereas 28 stenoses could not be confirmed by ICA. Twenty-two of them showed wall irregularities on ICA, and six were angiographically normal. Accordingly, on a coronary segmental basis, 28 false-positive and 0 false-negative findings resulted in a sensitivity of 100%, a specificity of 96.8%, a positive predictive value of 54.8%, and a negative predictive value of 100%. The diagnostic accuracy was 96.9%. Conclusion: Sixty-four-detector-row computed tomography reliably detects significant coronary stenoses in patients with suspected coronary artery disease and appears to be helpful in the selection of patients who need to undergo ICA. Calcified and non-calcified plaques are detected. Grading of stenoses in areas with calcification is difficult. Frequently, stenosis severity is overestimated by 64-detector-row computed tomography.

Single-row versus double-row arthroscopic rotator cuff repair in small- to medium-sized tears.

Science.gov (United States)

Aydin, Nuri; Kocaoglu, Baris; Guven, Osman

2010-07-01

Double-row rotator cuff repair leads to superior cuff integrity and clinical results compared with single-row repair. The study enrolled 68 patients with a full-thickness rotator cuff tear who were divided into 2 groups of 34 patients according to repair technique. The patients were followed-up for at least 2 years. The results were evaluated by Constant score. Despite the biomechanical studies and cadaver studies that proved the superiority of double-row fixation over single-row fixation, our clinical results show no difference in functional outcome between the two methods. It is evident that double-row repair is more technically demanding, expensive, and time-consuming than single-row repair, without providing a significant improvement in clinical results. Comparison between groups did not show significant differences. At the final follow-up, the Constant score was 82.2 in the single-row group and 78.8 in the double-row group. Functional outcome was improved in both groups after surgery, but the difference between the 2 groups was not significant. At long-term follow-up, arthroscopic rotator cuff repair with the double-row technique showed no significant difference in clinical outcome compared with single-row repair in small to medium tears. 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

A clinical study of acute cerebral infarction with a midline shift on the CT scan

International Nuclear Information System (INIS)

Takemae, Toshiki; Mizukami, Masahiro; Kin, Hiroshi; Kawase, Takeshi; Araki, Goro

1978-01-01

Twenty-one cases of acute cerebral infarction with a midline shift on the CT scan were studied with respect to the development of the midline shift, the angiographic findings, the clinical pictures and the outcome of these patients. The CT findings of hemorrhagic infarction were also studied. No cases showed a midline shift on a CT scan taken within 6 hours after the onset. A midline shift was, however, noted as early as 9 hours after the onset, and it reached its peak between the 2nd and 7th day of the onset. It gradually disappeared by the end of the third week. Hemorrhagic infarction was diagnosed in 6 patients by either spinal tap or autopsy. The CT findings of these hemorrhagic infarction were divided into two types, solid hemorrhages with an unequivocal high density within the low-density area, and small, scattered hemorrhagic of almost the same density as normal brain tissue within the low-density area. In 19 of 21 patients, an round-edged occlusion and/or embolus were observed on the initial angiograms. The recanalization of the occluded vessels was proved in 10 of 14 patients by subsequent angiographic studies. Twenty of 21 patients showed a sudden development of neurological symptoms, and 15 patients had a history of various kinds of heart disease, such as atrial fibrillation, valvular heart disease and myocardial infarction. The patients had atrial fibrillation on EKG on admission. These angiographic findings and clinical pictures strongly suggest that the infarction with a midline shift on the CT scan may be caused by a cerebral embolism of cardiac origin. Eight patients died of cerebral herniation between the 2nd and 6th day of the onset. Taking these poor outcomes into consideration, surgical as well as medical decompression of the brain would seem to be most important when the CT scan shows a midline shift. (author)

Prevalence of Congenital Coronary Artery Anomalies and Variants in 2697 Consecutive Patients Using 64-Detector Row Coronary CTAngiography

International Nuclear Information System (INIS)

Shabestari, Abbas Arjmand; Akhlaghpoor, Shahram; Tayebivaljozi, Reza; Fattahi Masrour, Farzaneh

2012-01-01

Coronary artery anomalies are not common, but could be very serious. This study determines the frequency of coronary anomalies and normal variants by multi-detector-row computed tomography (MDCT). The results of cardiac MDCT study in 2697 consecutive patients were analyzed retrospectively. Acquisition was performed by a 64-detector row CT machine. Imaging results were assessed by experienced radiologists. Myocardial bridging was by far the most frequent coronary variant (n = 576, 21.3%). Eighty-three subjects (3.1%) showed other coronary anomalies and variants. Anomalies of origination and course of the left main coronary artery (LMCA) were detected in 1.09% of the subjects. The frequency of these anomalies in the right coronary artery (RCA), left circumflex artery (LCx), left anterior descending artery (LAD), posterior descending artery (PDA) and obtuse marginal (OM) artery were 1.24%, 0.33%, 0.1%, 0.07% and 0.03%, respectively. The single coronary pattern was seen in 0.18% and coronary fistulas in 0.07%. Based on the fact that coronary CT-angiography using MDCT can display different coronary anomalies, this study shows similar results to other reports on the subject. Future advances in the performance of CT machines will further improve the quality of CT-based cardiac imaging

Thin-section CT of lung without ECG gating: 64-detector row CT can markedly reduce cardiac motion artifact which can simulate lung lesions

International Nuclear Information System (INIS)

Yanagawa, Masahiro; Tomiyama, Noriyuki; Sumikawa, Hiromitsu; Inoue, Atsuo; Daimon, Tadahisa; Honda, Osamu; Mihara, Naoki; Johkoh, Takeshi; Nakamura, Hironobu

2009-01-01

Purpose: Motion artifacts, which can mimic thickened bronchial wall and the cystic appearance of bronchiectasis, constitute a potential pitfall in the diagnosis of interstitial or bronchial disease. Therefore, purpose of our study was to evaluate whether 64-detector row CT (64-MDCT) enables a reduction in respiratory or cardiac motion artifacts in the lung area on thin-section CT without ECG gating, and to examine the correlation between cardiac motion artifact and heart rate. Materials and methods: Thirty-two patients with suspected diffuse lung disease, who underwent both 8- and 64-MDCT (gantry rotation time, 0.5 and 0.4 s, respectively), were included. The heart rates of an additional 155 patients were measured (range, 48-126 beats per minute; mean, 76 beats per minute) immediately prior to 64-MDCT, and compared to the degree of cardiac motion artifact. Two independent observers evaluated the following artifacts on a monitor without the knowledge of relevant clinical information: (1) artifacts on 8- and 64-MDCT images with 1.25-mm thickness and those on 64-MDCT images with 0.625-mm thickness in 32 patients; and (2) artifacts on 64-MDCT images with 0.625-mm thickness in 155 patients. Results: Interobserver agreement was good in evaluating artifacts on 8-MDCT images with 1.25-mm thickness (weighted Kappa test, κ = 0.61-0.71), and fair or poor in the other evaluations (κ < 0.31). Two observers stated that cardiac motion artifacts were more significant on 8-MDCT than on 64-MDCT in all 32 patients. Statistically significant differences were found at various checkpoints only in comparing artifacts between 8- and 64-MDCT for 1.25-mm thickness (Wilcoxon's signed-rank test, p < 0.0017). Cardiac motion artifacts on 64-MDCT had no significant correlation with heart rate (Spearman's correlation coefficient by rank test). Conclusion: The high temporal resolution of 64-MDCT appears to reduce cardiac motion artifact that can affect thin-section scans of the lung parenchyma

Thin-section CT of lung without ECG gating: 64-detector row CT can markedly reduce cardiac motion artifact which can simulate lung lesions

Energy Technology Data Exchange (ETDEWEB)

Yanagawa, Masahiro [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan)], E-mail: m-yanagawa@radiol.med.osaka-u.ac.jp; Tomiyama, Noriyuki; Sumikawa, Hiromitsu; Inoue, Atsuo [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Daimon, Tadahisa [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Department of Medicine, Division of Pulmonary Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498 (Japan); Honda, Osamu [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Mihara, Naoki [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Department of Radiology, Osaka Advanced Medical Imaging Center, 5-20-1 Momoyamadai, Suita-city, Osaka 565-0854 (Japan); Johkoh, Takeshi [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Department of Medical Physics, Osaka University Graduate School of Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Nakamura, Hironobu [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan)

2009-01-15

Purpose: Motion artifacts, which can mimic thickened bronchial wall and the cystic appearance of bronchiectasis, constitute a potential pitfall in the diagnosis of interstitial or bronchial disease. Therefore, purpose of our study was to evaluate whether 64-detector row CT (64-MDCT) enables a reduction in respiratory or cardiac motion artifacts in the lung area on thin-section CT without ECG gating, and to examine the correlation between cardiac motion artifact and heart rate. Materials and methods: Thirty-two patients with suspected diffuse lung disease, who underwent both 8- and 64-MDCT (gantry rotation time, 0.5 and 0.4 s, respectively), were included. The heart rates of an additional 155 patients were measured (range, 48-126 beats per minute; mean, 76 beats per minute) immediately prior to 64-MDCT, and compared to the degree of cardiac motion artifact. Two independent observers evaluated the following artifacts on a monitor without the knowledge of relevant clinical information: (1) artifacts on 8- and 64-MDCT images with 1.25-mm thickness and those on 64-MDCT images with 0.625-mm thickness in 32 patients; and (2) artifacts on 64-MDCT images with 0.625-mm thickness in 155 patients. Results: Interobserver agreement was good in evaluating artifacts on 8-MDCT images with 1.25-mm thickness (weighted Kappa test, {kappa} = 0.61-0.71), and fair or poor in the other evaluations ({kappa} < 0.31). Two observers stated that cardiac motion artifacts were more significant on 8-MDCT than on 64-MDCT in all 32 patients. Statistically significant differences were found at various checkpoints only in comparing artifacts between 8- and 64-MDCT for 1.25-mm thickness (Wilcoxon's signed-rank test, p < 0.0017). Cardiac motion artifacts on 64-MDCT had no significant correlation with heart rate (Spearman's correlation coefficient by rank test). Conclusion: The high temporal resolution of 64-MDCT appears to reduce cardiac motion artifact that can affect thin-section scans of

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.

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

Diagnostic performance of combined noninvasive coronary angiography and myocardial perfusion imaging using 320 row detector computed tomography

DEFF Research Database (Denmark)

Vavere, Andrea L; Simon, Gregory G; George, Richard T

2013-01-01

Multidetector coronary computed tomography angiography (CTA) is a promising modality for widespread clinical application because of its noninvasive nature and high diagnostic accuracy as found in previous studies using 64 to 320 simultaneous detector rows. It is, however, limited in its ability...... to detect myocardial ischemia. In this article, we describe the design of the CORE320 study ("Combined coronary atherosclerosis and myocardial perfusion evaluation using 320 detector row computed tomography"). This prospective, multicenter, multinational study is unique in that it is designed to assess...... the diagnostic performance of combined 320-row CTA and myocardial CT perfusion imaging (CTP) in comparison with the combination of invasive coronary angiography and single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). The trial is being performed at 16 medical centers located in 8...

Importance of stand density, inter row spacing, "mother" and "father" row distance in corn seed production

Directory of Open Access Journals (Sweden)

Marinković Branko

2006-01-01

Full Text Available Importance of stand density, "mother" and "father" row distance is very important for corn seed production. Inter row spacing from 70,60 and 50 cm, and their influence on "mother" grain yield was investigated during 7 years trials. In seed production, at density ratio 6 + 2, beside inter row spacing, yield influence on stand density was followed as well. Five stand densities (40.8000, 52.900, 64.900, 79.400, 89.300, total plant number per ha and density ration 6 + 2, was investigated. The next results were obtained: at 70 cm inter row spacing, the highest yield was achieved with the 64.900 plant/ha stand density (4.35 tha-1 "mother" seed. At the first row, yield was higher for 360 and 550 kgha-1 in dependence from the second and the third "mother" row. At 60 cm inter row spacing, yield was increasing till the highest density, and significant difference, in relation to 40.800 plants/ha, was at 79.400 plants/ha stands density. At the second and the third row in rela­tion to the first "mother" row, yield difference was 430 and 510 kgha-1. The same conclusions can be made at the 50 cm inter row spacing. With the "mother" row space increasing, yield was decreased for 370 and 460 kgha-1.

Current development of cardiac imaging with multidetector-row CT

International Nuclear Information System (INIS)

Becker, Christoph R.; Ohnesorge, Bernd M.; Schoepf, U. Joseph; Reiser, Maximilian F.

2000-01-01

Multidector-row CT (MDCT) with retrospective ECG gating allows scanning the entire heart with 1.25 mm slice thickness and 250 ms effective exposure time within 35 s investigation time. The resulting images allow for an accurate high-resolution assessment of morphological detail of both the coronary arteries and the cardiac chambers. Performing a contrast-enhanced MDCT angiography (MD-CTA) in addition to a non-enhanced scan for the detection and quantification of coronary calcifications may be indicated in patients with atypical chest pain and in young patients with high cardiovascular risk. This group of patients may show non-calcified plaques as the first sign of their coronary artery disease. As the proximal part of the coronary arteries is well displayed by MD-CTA it also helps to delineate the course in anomalous coronary vessels. Additional information is drawn from the preoperative use of MD-CTA do determine the distance of the left internal mammarian artery to the left anterior descending coronary artery prior to minimal invasive bypass grafting. Additional indications for MD-CTA are the non-invasive follow up after venous bypass grafting, PTCA, and coronary stent interventions. MD-CTA allows following the course of the coronary vessels to the level of third generation coronary segmental arteries. A definite diagnosis to rule out coronary artery disease can be reliably made in vessels with a diameter of 1.5 mm or greater. With MDCT a number of different atherosclerotic changes can be observed in diseased coronary arteries. Non-stenotic lesions may show tiny calcifications surrounded by large areas of irregularly distributed soft tissue. Calcifications in this type of atherosclerotic coronary artery wall changes appear as 'the tip of iceberg'. Heavy calcifications usually tend to be non-stenotic because of vessel remodelling resulting in a widening of the coronary vessel lumen. Therefore, heavy calcifications appear to act like an 'internal stent' for a

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

Diagnosis of clinical staging of bladder cancer by CT and angiography

International Nuclear Information System (INIS)

Kobayashi, Isao; Igawa, Mikio; Ohnishi, Yoshio; Nakano, Hiroshi; Nihira, Hiromi; Mori, Masaki; Okada, Mitsuo.

1984-01-01

The preoperative staging of bladder cancer is of fundamental importance for prognostic evaluation and surgical indication. We studied the accuracy of computed tomography (CT) and angiography in defining the extent of local invasion in 16 patients with surgically proven carcinoma of the bladder. The overall accuracy of CT and angiographic staging in these cases was 75 % and 50 % respectively. In low stage, the accuracy was 90 % in CT and 70 % in angiography. In high stage, the accuracy was 50 % in CT and 16.7 % in angiography. Our results seems to indicate lower accuracy in high stage bladder cancer compared with other research. Data from a much larger series are required to ascertain whether the additional information provided by CT and angiography will produce any improvement in patient management. (author)

Influence of detector collimation and beam pitch for identification and image quality of ground-glass attenuation and nodules on 16- and 64-detector row CT systems: experimental study using chest phantom.

Science.gov (United States)

Ohno, Yoshiharu; Koyama, Hisanobu; Kono, Astushi; Terada, Mari; Inokawa, Hiroyasu; Matsumoto, Sumiaki; Sugimura, Kazuro

2007-12-01

The purpose of the present study was to determine the influence of detector collimation and beam pitch for identification and image quality of ground-glass attenuation (GGA) and nodules on 16- and 64-detector row CTs, by using a commercially available chest phantom. A chest CT phantom including simulated GGAs and nodules was scanned with different detector collimations, beam pitches and tube currents. The probability and image quality of each simulated abnormality was visually assessed with a five-point scoring system. ROC-analysis and ANOVA were then performed to compare the identification and image quality of either protocol with standard values. Detection rates of low-dose CTs were significantly reduced when tube currents were set at 40mA or less by using detector collimation 16 and 64x0.5mm and 16 and 32mmx1.0mm for low pitch, and at 100mA or less by using detector collimation 16 and 64x0.5mm and 16 and 32mmx1.0mm for high pitch (pdetector collimation 16 and 64x0.5mm and 16 and 32x1.0mm for low pitch, and at 150mA or less by using detector collimation 16 and 64x0.5mm and 16 and 32x1.0mm for high pitch (pDetector collimation and beam pitch were important factors for the image quality and identification of GGA and nodules by 16- and 64-detector row CT.

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.

Angiographic embolization in the treatment of intrahepatic arterial bleeding in patients with blunt abdominal trauma.

Science.gov (United States)

Kong, Ya-Lin; Zhang, Hong-Yi; He, Xiao-Jun; Zhao, Gang; Liu, Cheng-Li; Xiao, Mei; Zhen, Yu-Ying

2014-04-01

Angiographic embolization (AE) as an adjunct non-operative treatment of intrahepatic arterial bleeding has been widely used. The present study aimed to evaluate the efficacy of selective AE in patients with hepatic trauma. Seventy patients with intrahepatic arterial bleeding after blunt abdominal trauma who had undergone selective AE in 10 years at this institution were retrospectively reviewed. The criteria for selective AE included active extravasation on contrast-enhanced CT, an episode of hypotension or a decrease in hemoglobin level during the non-operative treatment. The data of the patients included demographics, grade of liver injuries, mechanism of blunt abdominal trauma, associated intra-abdominal injuries, indications for AE, angiographic findings, type of AE, and AE-related hepatobiliary complications. In the 70 patients, 32 (45.71%) had high-grade liver injuries. Extravazation during the early arterial phase mainly involved the right hepatic segments. Thirteen (18.57%) patients underwent embolization of intrahepatic branches and the extrahepatic trunk and these patients all developed AE-related hepatobiliary complications. In 19 patients with AE-related complications, 14 received minimally invasive treatment and recovered without severe sequelae. AE is an adjunct treatment for liver injuries. Selective and/or super-selective AE should be advocated to decrease the incidence and severity of AE-related hepatobiliary complications.

The selective angiographic diagnosis and endovascular embolization treatment of severe epistaxis

International Nuclear Information System (INIS)

Zhang Xiquan; Lu Yonghong; Sun Jinghua; Guo Deqiang; Li Yuzhen; Wei Aihua

2002-01-01

Objective: To evaluate selective angiographic diagnosis and embolization of severe epistaxis in 57 cases. Methods: 41 cases with spontaneous haemorrhage, 11 cases with traumatic haemorrhage, 3 cases with haemorrhage of nasopharyngeal fibroangioma, and 2 case with haemorrhage of nasopharyngeal carcinoma were included in the study. Selective angiographic diagnosis and embolization of epistaxis were performed with absorbable gelatin sponge or balloon or spring coil by using Seldinger's method. Results: 59 procedure of angiographic diagnosis and embolization were performed in 57 cases. Both maxillaris internal artery embolization was performed in 6 cases. After embolization, satisfactory results were achieved immediately in 55 cases. After 6 months to 2 years' follow-up, no haemorrhage recurred. In 4 cases with traumatic haemorrhage in the face, simple maxillaris internal artery embolization was performed in 2 cases. Conclusion: Selective angiographic diagnosis and embolization are safe, effective, and successful method of choices in the treatment of severe epistaxis

Meta-analysis of Clinical and Radiographic Outcomes After Arthroscopic Single-Row Versus Double-Row Rotator Cuff Repair.

Science.gov (United States)

Perser, Karen; Godfrey, David; Bisson, Leslie

2011-05-01

Double-row rotator cuff repair methods have improved biomechanical performance when compared with single-row repairs. To review clinical outcomes of single-row versus double-row rotator cuff repair with the hypothesis that double-row rotator cuff repair will result in better clinical and radiographic outcomes. Published literature from January 1980 to April 2010. Key terms included rotator cuff, prospective studies, outcomes, and suture techniques. The literature was systematically searched, and 5 level I and II studies were found comparing clinical outcomes of single-row and double-row rotator cuff repair. Coleman methodology scores were calculated for each article. Meta-analysis was performed, with treatment effect between single row and double row for clinical outcomes and with odds ratios for radiographic results. The sample size necessary to detect a given difference in clinical outcome between the 2 methods was calculated. Three level I studies had Coleman scores of 80, 74, and 81, and two level II studies had scores of 78 and 73. There were 156 patients with single-row repairs and 147 patients with double-row repairs, both with an average follow-up of 23 months (range, 12-40 months). Double-row repairs resulted in a greater treatment effect for each validated outcome measure in 4 studies, but the differences were not clinically or statistically significant (range, 0.4-2.2 points; 95% confidence interval, -0.19, 4.68 points). Double-row repairs had better radiographic results, but the differences were also not statistically significant (P = 0.13). Two studies had adequate power to detect a 10-point difference between repair methods using the Constant score, and 1 study had power to detect a 5-point difference using the UCLA (University of California, Los Angeles) score. Double-row rotator cuff repair does not show a statistically significant improvement in clinical outcome or radiographic healing with short-term follow-up.

Biomechanical comparison of a single-row versus double-row suture anchor technique for rotator cuff repair.

Science.gov (United States)

Kim, David H; Elattrache, Neal S; Tibone, James E; Jun, Bong-Jae; DeLaMora, Sergai N; Kvitne, Ronald S; Lee, Thay Q

2006-03-01

Reestablishment of the native footprint during rotator cuff repair has been suggested as an important criterion for optimizing healing potential and fixation strength. A double-row rotator cuff footprint repair will demonstrate superior biomechanical properties compared with a single-row repair. Controlled laboratory study. In 9 matched pairs of fresh-frozen cadaveric shoulders, the supraspinatus tendon from 1 shoulder was repaired with a double-row suture anchor technique: 2 medial anchors with horizontal mattress sutures and 2 lateral anchors with simple sutures. The tendon from the contralateral shoulder was repaired using a single lateral row of 2 anchors with simple sutures. Each specimen underwent cyclic loading from 10 to 180 N for 200 cycles, followed by tensile testing to failure. Gap formation and strain over the footprint area were measured using a video digitizing system; stiffness and failure load were determined from testing machine data. Gap formation for the double-row repair was significantly smaller (P row repair for the first cycle (1.67 +/- 0.75 mm vs 3.10 +/- 1.67 mm, respectively) and the last cycle (3.58 +/- 2.59 mm vs 7.64 +/- 3.74 mm, respectively). The initial strain over the footprint area for the double-row repair was nearly one third (P row repair. Adding a medial row of anchors increased the stiffness of the repair by 46% and the ultimate failure load by 48% (P row repair improved initial strength and stiffness and decreased gap formation and strain over the footprint when compared with a single-row repair. To achieve maximal initial fixation strength and minimal gap formation for rotator cuff repair, reconstructing the footprint attachment with 2 rows of suture anchors should be considered.

Intra-arterial angio-CT for radiosurgery of cerebral arteriovenous malformations

International Nuclear Information System (INIS)

Tanami, Yutaka; Kunieda, Etsuo; Onozuka, Satoshi

1998-01-01

Intra-arterial CT-angiograms were performed for four patients undergoing stereotactic radiosurgery for cerebral arteriovenous malformations (AVM). Helical and dynamic CT scans were carried out with a scanner installed in a angiographic examination room following routine angiography. Helical scans were performed with continuous arterial infusion of contrast media. Then, dynamic scans were repeated at several table positions. Subtractions were achieved for a post-embolization case. Normal and pathological vascular structures were demonstrated with different enhancement phases with the dynamic scans. The coordinates of the target points in the nidus could be clearly determined. We concluded that intra-arterial CT-angiograms are practical and useful for treatment planning of radiosurgery for cerebral AVM. (author)

Intra-arterial angio-CT for radiosurgery of cerebral arteriovenous malformations

Energy Technology Data Exchange (ETDEWEB)

Tanami, Yutaka; Kunieda, Etsuo; Onozuka, Satoshi [Keio Univ., Tokyo (Japan) School of Medicine] [and others

1998-08-01

Intra-arterial CT-angiograms were performed for four patients undergoing stereotactic radiosurgery for cerebral arteriovenous malformations (AVM). Helical and dynamic CT scans were carried out with a scanner installed in a angiographic examination room following routine angiography. Helical scans were performed with continuous arterial infusion of contrast media. Then, dynamic scans were repeated at several table positions. Subtractions were achieved for a post-embolization case. Normal and pathological vascular structures were demonstrated with different enhancement phases with the dynamic scans. The coordinates of the target points in the nidus could be clearly determined. We concluded that intra-arterial CT-angiograms are practical and useful for treatment planning of radiosurgery for cerebral AVM. (author)

Intra-arterial CT-angiography for cerebral arteriovenous malformation--initial experiences for treatment planning of radiosurgery

International Nuclear Information System (INIS)

Kunieda, Etsuo; Kawaguchi, Osamu; Onozuka, Satoshi; Momoshima, Suketaka; Takeda, Atsuya; Shigematsu, Naoyuki; Hashimoto, Subaru; Ohira, Takayuki; Kubo, Atsushi

2002-01-01

Purpose: To clarify the feasibility and effectiveness of intra-arterial CT angiography (IACTA) for treatment planning of arteriovenous malformation radiosurgery. Methods and Materials: A CT scanner installed in an angiographic examination room was used. Helical IACTA was performed in 22 patients during continuous intra-arterial infusion of contrast medium via the internal carotid or vertebral artery, and dynamic IACTA was performed in 20 of these patients with reconstruction at 0.2-s intervals. The dynamic IACTA was repeated for each 3- or 5-mm increment to encompass the nidus. Subtractions were performed in postembolization cases. A retrospective review of IACTA was performed to assess the effectiveness of dynamic scans. Results: No complications related to the angiographic procedure or CT imaging were detected. High contrast enhancement was obtained for both helical and dynamic IACTA. In 18 of the 20 cases (90%), draining veins were separated from the nidus by using the enhancement patterns, and in 13 cases (65%), feeding arteries were separated. Conclusion: Dynamic IACTA added important information for target-volume determinations. Conventional CT and MRI could be omitted from the protocol, and the period that patients wore the frame was substantially shortened. We conclude that IACTA is a practical and useful method for radiosurgical treatment planning of arteriovenous malformations

A comparison of chemoembolization endpoints using angiographic versus transcatheter intraarterial perfusion/MR imaging monitoring.

Science.gov (United States)

Lewandowski, Robert J; Wang, Dingxin; Gehl, James; Atassi, Bassel; Ryu, Robert K; Sato, Kent; Nemcek, Albert A; Miller, Frank H; Mulcahy, Mary F; Kulik, Laura; Larson, Andrew C; Salem, Riad; Omary, Reed A

2007-10-01

Transcatheter arterial chemoembolization (TACE) is an established treatment for unresectable liver cancer. This study was conducted to test the hypothesis that angiographic endpoints during TACE are measurable and reproducible by comparing subjective angiographic versus objective magnetic resonance (MR) endpoints of TACE. The study included 12 consecutive patients who presented for TACE for surgically unresectable HCC or progressive hepatic metastases despite chemotherapy. All procedures were performed with a dedicated imaging system. Angiographic series before and after TACE were reviewed independently by three board-certified interventional radiologists. A subjective angiographic chemoembolization endpoint (SACE) classification scheme, modified from an established angiographic grading system in the cardiology literature, was designed to assist in reproducibly classifying angiographic endpoints. Reproducibility in SACE classification level was compared among operators, and MR imaging perfusion reduction was compared with SACE levels for each observer. Twelve patients successfully underwent 15 separate TACE sessions. SACE levels ranged from I through IV. There was moderate agreement in SACE classification (kappa = 0.46 +/- 0.12). There was no correlation between SACE level and MR perfusion reduction (r = 0.16 for one operator and 0.02 for the other two). Angiographic endpoints during TACE vary widely, have moderate reproducibility among operators, and do not correlate with functional MR imaging perfusion endpoints. Future research should aim to determine ideal angiographic and functional MR imaging endpoints for TACE according to outcome measures such as imaging response, pathologic response, and survival.

ECG-triggered MDR-CT for the detection of pulmonary metastases

International Nuclear Information System (INIS)

Pauls, S.; Wahl, J.; Aschoff, A.J.; Brambs, H.J.; Fleiter, T.R.

2003-01-01

Purpose: Comparison of multidetector-row CT (MDR-CT) of the chest with and without ECG triggering for the detection of pulmonary metastases. Materials and Methods: Fifty patients with malignant tumors underwent CT of the chest. The unenhanced phase was performed with ECG-triggered MDR-CT and the contrast-enhanced phase with helical MDR-CT. The ECG-triggered and standard helical scans were interpreted in separate sessions, with the analysis determining the number and demarcation of the intrapulmonary nodules and the delineation of the mediastinal structure (rated 1 = excellent to 5 = poor). Results: ECG-MDR-CT images detected 38% more pulmonary nodules than MDR-CT. The detection rate for tumors [de

Meta-analysis of Clinical and Radiographic Outcomes After Arthroscopic Single-Row Versus Double-Row Rotator Cuff Repair

OpenAIRE

Perser, Karen; Godfrey, David; Bisson, Leslie

2011-01-01

Context: Double-row rotator cuff repair methods have improved biomechanical performance when compared with single-row repairs. Objective: To review clinical outcomes of single-row versus double-row rotator cuff repair with the hypothesis that double-row rotator cuff repair will result in better clinical and radiographic outcomes. Data Sources: Published literature from January 1980 to April 2010. Key terms included rotator cuff, prospective studies, outcomes, and suture techniques. Study Sele...

Angiographic findings of hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Han, Man Chung; Cho, Byung Jae; Huh, Seung Jae; Bae, Sang Hoon; Kim, Ung Jin; Kim, Chung Yong; Kim, Noe Kyeong [Yonsei University College of Medicine, Seoul (Korea, Republic of)

1985-12-15

From March 1977 to July 1979, 69 cases of angiograms of hepatocellular carcinoma were observed in Seoul National University Hospital. The findings of selective celiac and/or hepatic arteriography in total 69 cases of confirmed hepatocellular carcinoma, with clinical and laboratory findings, were analyzed. The summarized results are as follows; 1. Among 69 cases od hepatoma, 62 were male and 7 were female with sex ratio of 8.9 : 1. Peak incidence is 5th to 7th decades (72.5%). Epigastric pain, indigestion, and palpable mass in right upper quadrant were common symptoms and sign. Laboratory findings showed elevated serum alkaline phosphatase more than 5 Bodansky unit in 75.4%. Alpha-feto protein was positive in 65.2% of all the patients. 2 All 69 cases were classified into 31 cases of massive type, 22 cases of diffuse type, and 16 cases of nodular type, in accordance with angiographic gross anatomy. The frequency of angiographic findings were hypervascularities and tumor vessels (100%), tumor stainings (98.5%), arteriovenous shunt (71.0%), displacement of intrahepatic arteries (66.7%), vascular lakes and channel (59.4%). Encasement of hepatic artery and portal vein regurgitation was respectively 4 cases. Tumor mass in portal vein were 6 cases and tumor mass in hepatic vein was 1 case. 3. Intraarterial infusion of 5-FU was performed in 15 hepatoma patients, and the results were that angiographic improvement was demonstrated in 3 cases, no improvement in 8 cases, and incomplete infusion in 4 cases. 4. The selective celiac and/or hepatic angiograms are excellent diagnostic tools as well as therapeutic management for intraarterial infusion of anticancerous drugs.

Angiographic findings of hepatocellular carcinoma

International Nuclear Information System (INIS)

Han, Man Chung; Cho, Byung Jae; Huh, Seung Jae; Bae, Sang Hoon; Kim, Ung Jin; Kim, Chung Yong; Kim, Noe Kyeong

1985-01-01

From March 1977 to July 1979, 69 cases of angiograms of hepatocellular carcinoma were observed in Seoul National University Hospital. The findings of selective celiac and/or hepatic arteriography in total 69 cases of confirmed hepatocellular carcinoma, with clinical and laboratory findings, were analyzed. The summarized results are as follows; 1. Among 69 cases od hepatoma, 62 were male and 7 were female with sex ratio of 8.9 : 1. Peak incidence is 5th to 7th decades (72.5%). Epigastric pain, indigestion, and palpable mass in right upper quadrant were common symptoms and sign. Laboratory findings showed elevated serum alkaline phosphatase more than 5 Bodansky unit in 75.4%. Alpha-feto protein was positive in 65.2% of all the patients. 2 All 69 cases were classified into 31 cases of massive type, 22 cases of diffuse type, and 16 cases of nodular type, in accordance with angiographic gross anatomy. The frequency of angiographic findings were hypervascularities and tumor vessels (100%), tumor stainings (98.5%), arteriovenous shunt (71.0%), displacement of intrahepatic arteries (66.7%), vascular lakes and channel (59.4%). Encasement of hepatic artery and portal vein regurgitation was respectively 4 cases. Tumor mass in portal vein were 6 cases and tumor mass in hepatic vein was 1 case. 3. Intraarterial infusion of 5-FU was performed in 15 hepatoma patients, and the results were that angiographic improvement was demonstrated in 3 cases, no improvement in 8 cases, and incomplete infusion in 4 cases. 4. The selective celiac and/or hepatic angiograms are excellent diagnostic tools as well as therapeutic management for intraarterial infusion of anticancerous drugs.

Influence of a combined CT/C-arm system on periprocedural workflow and procedure times in mechanical thrombectomy.

Science.gov (United States)

Pfaff, Johannes; Schönenberger, Silvia; Herweh, Christian; Pham, Mirko; Nagel, Simon; Ringleb, Peter Arthur; Heiland, Sabine; Bendszus, Martin; Möhlenbruch, Markus Alfred

2017-09-01

To achieve the fastest possible workflow in ischaemic stroke, we developed a CT/C-arm system, which allows imaging and endovascular treatment on the same patient table. This prospective, monocentric trial was conducted between October 2014 and August 2016. Patients received stroke imaging and mechanical thrombectomy under general anaesthesia (GA) or conscious sedation (CS) using our combined setup comprising a CT-scanner and a mobile C-arm X-ray device. Primary endpoint was time between stroke imaging and groin puncture. We compared periprocedural workflow and procedure times with the literature and a matched patient cohort treated with a biplane angiographic system before installation of the CT/C-arm system. In 50 patients with acute ischaemic stroke due to large-vessel occlusion in the anterior circulation, comparable recanalization rates were achieved by using the CT/C-arm setup (TICI2b-3:CT/C-arm-GA: 85.7%; CT/C-arm-CS: 90.9%; Angiosuite: 78.6%; p = 0.269) without increasing periprocedural complications. Elimination of patient transport resulted in a significant reduction of the time between stroke imaging and groin puncture: median, min (IQR): CT/C-arm-GA: 43 (35-52); CT/C-arm-CS: 39 (28-49); Angiosuite: 64 (48-74); p < 0.0001. The combined CT/C-arm system allows comparable recanalization rates as a biplane angiographic system and accelerates the start of the endovascular stroke treatment. • The CT/C-arm setup reduces median time from stroke imaging to groin puncture. • Mechanical thrombectomy using a C-arm device is feasible without increasing peri-interventional complications. • The CT/C-arm setup might be a valuable fallback solution for emergency procedures. • The CT/C-arm setup allows immediate control CT images during and after treatment.

CT Angiographic Demonstration of a Mesenteric Vessel 'Whirlpool' in Intestinal Malrotation and Midgut Volvulus: a Case Report

Energy Technology Data Exchange (ETDEWEB)

Bozlar, Ugur; Ugurel, Mehmet Sahin; Ustunsoz, Bahri [Gulhane Military Medical Academy, Ankara (Turkmenistan); Coskun, Unsal [Gulhane Military Medical Academy, Turkish Armed Forces Rehabilitation Center, Ankara (Turkmenistan)

2008-10-15

Although the color Doppler ultrasonography diagnosis of intestinal malrotation with midgut volvulus, based on the typical 'whirlpool' appearance of the mesenteric vascular structures is well-defined in the peer-reviewed literature, the combination of both the angiographic illustration of these findings and the contemporary state-of-the-art imaging techniques is lacking. We report the digital subtraction angiography and multidetector computed tomography angiography findings of a 37-year-old male with intestinal malrotation.

Multidetector-row CT of right hemidiaphragmatic rupture caused by blunt trauma: a review of 12 cases

International Nuclear Information System (INIS)

Rees, O.; Mirvis, S.E.; Shanmuganathan, K.

2005-01-01

AIM: To determine the usefulness of multidetector-row CT (MDCT) with multiplanar reformatted (MPR) images in the sagittal and coronal plane in diagnosing acute right hemidiaphragmatic rupture. MATERIALS AND METHODS: Twelve patients were identified who received chest and abdominal MDCT after major blunt trauma diagnosed with right diaphragmatic injury. Sagittal and coronal reformations were performed in all cases. The images were retrospectively reviewed by two experienced radiologists for signs of right diaphragm injury, such as direct diaphragm discontinuity, the 'collar sign', the 'dependent viscera sign', and intra-thoracic location of herniated abdominal contents. RESULTS: Of the 12 cases of right hemidiaphragm rupture, diaphragm discontinuity was seen in seven (58%) cases, the collar sign in five (42%), the dependent viscera sign in four (33%), and transdiaphragmatic herniation of the right colon and fat in another. Two variants of the collar sign were apparent on high-quality sagittal and coronal reformations. The first, termed the 'hump sign', describes a rounded portion of liver herniating through the diaphragm forming a hump-shaped mass, and the second, termed the 'band sign,' is a linear lucency across the liver along the torn edges of the hemidiaphragm. The hump sign occurred in 10 (83%) patients and the band sign in four (33%). CONCLUSION: MDCT is very useful in the diagnosis of right hemidiaphragm injury caused by blunt trauma when sagittal and coronal reformatted images are obtained, and should allow more frequent preoperative diagnosis

Imaging of peripheral arteries by 16-row multidetector computed tomography angiography: A feasible tool?

Energy Technology Data Exchange (ETDEWEB)

Mishra, Anuj [Department of Radiology, National Organ Transplant Program, Tripoli (Libyan Arab Jamahiriya)]. E-mail: dranujmish@yahoo.com; Bhaktarahalli, Jahnavi Narayanaswamy [Department of Clinical Pathology, Tripoli Medical Centre, Tripoli (Libyan Arab Jamahiriya); Ehtuish, Ehtuish F. [Department of Surgery, National Organ Transplant Program, Tripoli (Libyan Arab Jamahiriya)

2007-03-15

Objective: To evaluate the efficacy of multidetector (16-row) computed tomography (MDCT) in imaging the upper and lower limb arterial tree in trauma and peripheral arterial occlusive disease (PAOD). Methods: Thirty-three patients underwent MDCT angiography (MDCTA) of the upper or the lower limb on 16-row MDCT scanner between November, 2004 and July, 2005. The findings were compared with the surgical outcome in cases with trauma and suspected arterial injuries or color Doppler correlation was obtained for patients of PAOD. Results: MDCTA allowed a comprehensive diagnostic work-up in all trauma cases with suspected arterial injuries. In the 23 cases of PAOD, MDCT adequately demonstrated the presence of stenosis or occlusion, its degree and extent, the presence of collaterals and plaques. Conclusion: Our experience of CT angiography (CTA) with 16-row MDCT scanner has clearly demonstrated its efficacy as a promising, new, fast, accurate, safe and non-invasive imaging modality of choice in cases of trauma with suspected arterial injuries and as a useful screening modality in cases of PAOD for diagnosis and for grading.

Imaging of peripheral arteries by 16-row multidetector computed tomography angiography: A feasible tool?

International Nuclear Information System (INIS)

Mishra, Anuj; Bhaktarahalli, Jahnavi Narayanaswamy; Ehtuish, Ehtuish F.

2007-01-01

Objective: To evaluate the efficacy of multidetector (16-row) computed tomography (MDCT) in imaging the upper and lower limb arterial tree in trauma and peripheral arterial occlusive disease (PAOD). Methods: Thirty-three patients underwent MDCT angiography (MDCTA) of the upper or the lower limb on 16-row MDCT scanner between November, 2004 and July, 2005. The findings were compared with the surgical outcome in cases with trauma and suspected arterial injuries or color Doppler correlation was obtained for patients of PAOD. Results: MDCTA allowed a comprehensive diagnostic work-up in all trauma cases with suspected arterial injuries. In the 23 cases of PAOD, MDCT adequately demonstrated the presence of stenosis or occlusion, its degree and extent, the presence of collaterals and plaques. Conclusion: Our experience of CT angiography (CTA) with 16-row MDCT scanner has clearly demonstrated its efficacy as a promising, new, fast, accurate, safe and non-invasive imaging modality of choice in cases of trauma with suspected arterial injuries and as a useful screening modality in cases of PAOD for diagnosis and for grading

Angiographic patterns of carotid-cavernous fistulas

International Nuclear Information System (INIS)

Georgieva, G.; Jekova, M.; Genov, P.; Hadjidekov, V.

2006-01-01

Full text: The aim of the study is to present our experience in angiographic evaluation of carotid-cavernous fistulas. 8 patients with carotid-cavernous fistula (6 men and 2 women, range of age from 15 to 62) are included in the study out of all undergone cerebral angiography for a four year period (1996 - 2000). All patients underwent CT brain examination, two out of 8 - MRI. Visualization of ipsi- and contra lateral cavernous sinus and ophthalmic vein dilatation are assessed. In all cases the communication between the internal carotid artery and the cavernous sinus has been assessed as direct. Near simultaneous visualization of the home internal carotid artery, the dilated ipsilateral cavernous sinus and dilated superior ophthalmic vein is found in 2 patients, simultaneous visualization of both cavernous sinuses - in two. In 1 patient the early visualization of the cavernous sinus through the fistula enabled visualization of ipsilateral main internal carotid artery from the contra lateral circulation through the communicating arteries.In 1 excessive contralateral cavernous sinus and contralateral superior ophthalmic vein dilatation is detected. In other 1 excessive flow to dilated ipsilateral cavernous sinus lead insufficient circulation in distal vessels. Digital subtraction Angiography remains the most suitable imaging method in carotid-cavernous fistula assessment regarding type of communication and level of following vessels morphology changes

Evaluation of multiple trauma victims with 16-row multidetector CT (MDCT): a time analysis

International Nuclear Information System (INIS)

Heyer, C.M.; Nicolas, V.

2005-01-01

Purpose: Description and time analysis of a 16-row MDCT protocol in the evaluation of multiple trauma patients considering transport, time of scanning, patient positioning, image reconstruction, and image interpretation. Materials and methods: Between May and December 2004, 60 multiple trauma patients underwent 16-row MDCT (Sensation, Siemens, Erlangen, Germany). The protocol included serial scanning of the head, spiral scanning of the cervical spine and contrast-enhanced spiral scanning of the thorax/abdomen with multiplanar reformations (MPR) of the thoracic/lumbar spine and the pelvis. All time intervals including transport, patient positioning, scanning, duration of MPR, total time in the examination room, and time to first and final image interpretation were prospectively evaluated. Furthermore, patient characteristics, trauma profiles, and mortality rates were recorded. Results: 46 male and 14 female patients (mean age 43.6 years) were enrolled in the study. Time analysis of 16-row MDCT revealed the following results (mean time standard deviation): Emergency room treatment and transport 19.2±6.7 min, patient positioning 16.5±6.5 min, scan duration 8.0±3.3 min, total time in examination room 24.5±7.2 min, image reconstruction including MPR 32.0±16.4 min, and time of first (16.4±4.7 min) and final image interpretation (82.5±30.4 min). Trauma profiles revealed thoracic injuries in 35/60 patients (58.3%), head injuries in 23/60 patients (38.3%), abdominal injuries in 15/60 patients (25.0%), injuries of the cervical (9/60 patients, 15.0%), thoracic (12/60 patients, 20.0%), and lumbar spine (19/60 patients, 31.7%), pelvic injuries in 13/60 patients (21.7%), and injuries of extremities in 39/60 patients (65.0%). The mortality rate was 21.7%. (orig.)

Evaluation of various image reconstruction parameters in lower extremity stents using multidetector-row CT angiography: initial findings

International Nuclear Information System (INIS)

Heuschmid, Martin; Wiesinger, Benjamin; Tepe, Gunnar; Luz, Oliver; Kopp, Andreas F.; Claussen, Claus D.; Duda, Stephan H.

2007-01-01

Image quality, visible lumen and patency of lower limb stents was assessed by multidetector-row computed tomography (MDCT) angiography using various reconstruction parameters and the results compared with conventional angiography. Fourteen patients (25 stents) were evaluated. From MDCT datasets, axial and coronal oblique reformations were reconstructed using differing reconstruction parameters (slice thickness, kernel, views). Artifacts and image quality were assessed using a five-degree scale (1=excellent, 5=poor). Visible stent diameter was measured. Stenosis severity was compared with calibrated catheter angiography. The image quality of medium and sharp image kernels were good/fair (1.9-2.4), while smooth kernel provided only acceptable/poor image quality (3.9-4.4). Coronal oblique images were rated superior to assess in-stent lumen rather than axial. Using medium and sharp kernels, the visible stent lumen was significantly greater than using smooth kernel (P<0.001). thirteen out of fourteen patients (24/25 stents) were correctly classified as patent. In one patient, in-stent stenosis (≥50%) was falsely diagnosed using CT angiography (CTA) with smooth kernel and was, therefore, rated as false positive. Coronal oblique views, as well as medium and sharp kernels, have shown the best results regarding image quality to assess stent patency in the lower limb. Therefore, MDCT could be a valuable non-invasive modality for stent imaging in the peripheral vasculature. (orig.)

CT of blunt pancreatic trauma-A pictorial essay

International Nuclear Information System (INIS)

Venkatesh, Sudhakar Kundapur; Wan, John Mun Chin

2008-01-01

Blunt trauma to pancreas is uncommon and clinical features are often non-specific and unreliable leading to possible delays in diagnosis and therefore increased morbidity. CT has been established as the imaging modality of choice for the diagnosis of abdominal solid-organ injury in the blunt trauma patient. The introduction of multidetector-row CT allows for high resolution scans and multiplanar reformations that improve diagnosis. Detection of pancreatic injuries on CT requires knowledge of the subtle changes produced by pancreatic injury. The CT appearance of pancreatic injury ranges from a normal initial appearance of the pancreas to active pancreatic bleeding. Knowledge of CT signs of pancreatic trauma and a high index of suspicion is required in diagnosing pancreatic injury

Dose modulated retrospective ECG-gated versus non-gated 64-row CT angiography of the aorta at the same radiation dose: Comparison of motion artifacts, diagnostic confidence and signal-to-noise-ratios

International Nuclear Information System (INIS)

Schernthaner, Ruediger E.; Stadler, Alfred; Beitzke, Dietrich; Homolka, Peter; Weber, Michael; Lammer, Johannes; Czerny, Martin; Loewe, Christian

2012-01-01

Purpose: To compare ECG-gated and non-gated CT angiography of the aorta at the same radiation dose, with regard to motion artifacts (MA), diagnostic confidence (DC) and signal-to-noise-ratios (SNRs). Materials and methods: Sixty consecutive patients prospectively randomized into two groups underwent 64-row CT angiography, with or without dose-modulated ECG-gating, of the entire aorta, due to several pathologies of the ascending aorta. MA and DC were both assessed using a four-point scale. SNRs were calculated by dividing the mean enhancement by the standard deviation. The dose-length-product (DLP) of each examination was recorded and the effective dose was estimated. Results: Dose-modulated ECG-gating showed statistically significant advantages over non-gated CT angiography, with regard to MA (p < 0.001) and DC (p < 0.001), at the aortic valve, at the origin of the coronary arteries, and at the dissection membrane, with a significant correlation (p < 0.001) between MA and DC. At the aortic wall, however, ECG-gated CT angiography showed statistically significant fewer MA (p < 0.001), but not a statistically significant higher DC (p = 0.137) compared to non-gated CT angiography. At the supra-aortic vessels and the descending aorta, the ECG-triggering showed no statistically significant differences with regard to MA (p = 0.861 and 0.526, respectively) and DC (p = 1.88 and 0.728, respectively). The effective dose of ECG-gated CT angiography (23.24 mSv; range, 18.43–25.94 mSv) did not differ significantly (p = 0.051) from that of non-gated CT angiography (24.28 mSv; range, 19.37–29.27 mSv). Conclusion: ECG-gated CT angiography of the entire aorta reduces MA and results in a higher DC with the same SNR, compared to non-gated CT angiography at the same radiation dose.

Ergometer rowing with and without slides

DEFF Research Database (Denmark)

Larsen, Anders Holsgaard; Jensen, K

2010-01-01

A rowing ergometer can be placed on a slide to imitate 'on-water' rowing. The present study examines I) possible differences in biomechanical and physiological variables of ergometer rowing with and without slides and II) potential consequences on training load during exercise. 7 elite oars......-women rowed in a randomized order in a slide or stationary ergometer at 3 predefined submaximal and at maximal intensity. Oxygen uptake was measured and biomechanical variables of the rowing were calculated based upon handle force (force transducer) and velocity/length (potentiometer) of the stroke. Stroke...

Added diagnostic benefit of 16-row whole-body spiral CT in patients with multiple trauma differentiated by region and injury severity according to the ATLS registered concept

International Nuclear Information System (INIS)

Maurer, M.H.; Knopke, S.; Schroeder, R.J.

2008-01-01

Purpose: to determine the added diagnostic benefit of using MS-CT in multiple trauma patients differentiated by severity of injury and affected body region. Materials and methods: a retrospective analysis was performed of the 16-row whole-body spiral CT findings in 275 multiple trauma patients (73% men, 27% women; age 39.6 ± 18.9 years) with regard to additional findings and new findings obtained with CT compared to the findings obtained by conventional projection radiography and abdominal ultrasound in the emergency room. The additional and new findings were differentiated by body region (head, face, chest, pelvis, abdomen, spine) and the degree of severity according to the three classes of injuries distinguished by the ATLS registered concept (class 1: simple injury, class 2: potentially life threatening, class 3: immediately life threatening). Results: a total of 921 additional findings (findings potentially relevant for further diagnosis and therapy in addition to the findings obtained by conventional radiography or ultrasound) were obtained by MS-CT in all patients. The distribution by number of patients and body region was as follows: 22 neck, 76 face, 125 chest, 112 abdomen, 50 pelvis, and 91 spine. Most additional findings were categorized as potentially life threatening (ATLS class 2). In addition, there were 439 completely new findings, involving the head in 128 patients (mostly ATLS class 3), the face in 18, the chest in 47, the abdomen in 26, and the spine in 9 patients. Most new findings involving the face, abdomen, and spine were ATLS class 2 injuries. (orig.)

Evaluation of detectability of right inferior phrenic artery root in dynamic CT

Energy Technology Data Exchange (ETDEWEB)

Sato, Osamu [Akashi Municipal Hospital, Hyogo (Japan); Kizu, Osamu; Shimizu, Toshihisa; Takahashi, Takeshi; Ohno, Koji; Ohmura, Makoto; Maeda, Tomoho

1995-05-01

We evaluated the detectability of the root of the right inferior phrenic artery in dynamic CT over the entire liver as used for the diagnosis of hepatocellular carcinoma. The results showed no detection in three cases, poor detection in seven, detection in 12 and good detection in eight. The right inferior phrenic artery could be detected in many cases. Identification was easier in cases with direct branching from the aorta. It can be concluded that for angiographic examination, dynamic CT over the entire liver is useful for catheterization to the right inferior phrenic artery. (author).

Evaluation of detectability of right inferior phrenic artery root in dynamic CT

International Nuclear Information System (INIS)

Sato, Osamu; Kizu, Osamu; Shimizu, Toshihisa; Takahashi, Takeshi; Ohno, Koji; Ohmura, Makoto; Maeda, Tomoho.

1995-01-01

We evaluated the detectability of the root of the right inferior phrenic artery in dynamic CT over the entire liver as used for the diagnosis of hepatocellular carcinoma. The results showed no detection in three cases, poor detection in seven, detection in 12 and good detection in eight. The right inferior phrenic artery could be detected in many cases. Identification was easier in cases with direct branching from the aorta. It can be concluded that for angiographic examination, dynamic CT over the entire liver is useful for catheterization to the right inferior phrenic artery. (author)

Hepatic dimple sign on CT

International Nuclear Information System (INIS)

Matsumoto, Kunihiko; Nakajima, Teiichi; Ishikawa, Nobuyoshi; Ebihara, Reiko; Saida, Yukihisa

1983-01-01

The ''Dimple sign'' has been coined by Baltaxe et al. in 1974 and was said to be useful angiographic sign of avascular tumor. Similar dimple can be seen in the margin of the liver on CT examination of the hepatic tumors. We called this hepatic dimple sign and its clinical usefulness on CT examination was studied with 133 cases of hepatic tumors. Among 133 cases, there were 68 cases of hepatocellular carcinoma, 57 cases of metastatic liver tumor, 5 cases of hemangioma of the liver and 3 cases of hepatoblastoma. Hepatic dimple sign was recognized on 2 cases of metastatic liver tumor, 1 case of hemangioma, and 1 case of carcinoma of the gallbladder with hepatic infiltration. Cases experienced in the affiliated hospitals were also studied. A case of hepatocellular carcinoma and a case of metastatic liver tumor were evaluated. These tumors were relativly large measuring over 5cm in the greatest diameter and low density areas were apparent on plain CT. Therefore, dimples in the hepatic margin seen in CT scan did not contribute to the diagnostic accuracy of the liver tumor in these cases. (author)

Hepatic dimple sign on CT

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Kunihiko; Nakajima, Teiichi; Ishikawa, Nobuyoshi; Ebihara, Reiko; Saida, Yukihisa

1983-06-01

The ''Dimple sign'' has been coined by Baltaxe et al. in 1974 and was said to be useful angiographic sign of avascular tumor. Similar dimple can be seen in the margin of the liver on CT examination of the hepatic tumors. We called this hepatic dimple sign and its clinical usefulness on CT examination was studied with 133 cases of hepatic tumors. Among 133 cases, there were 68 cases of hepatocellular carcinoma, 57 cases of metastatic liver tumor, 5 cases of hemangioma of the liver and 3 cases of hepatoblastoma. Hepatic dimple sign was recognized on 2 cases of metastatic liver tumor, 1 case of hemangioma, and 1 case of carcinoma of the gallbladder with hepatic infiltration. Cases experienced in the affiliated hospitals were also studied. A case of hepatocellular carcinoma and a case of metastatic liver tumor were evaluated. These tumors were relativly large measuring over 5cm in the greatest diameter and low density areas were apparent on plain CT. Therefore, dimples in the hepatic margin seen in CT scan did not contribute to the diagnostic accuracy of the liver tumor in these cases. (author).

Usefulness of CT angiography after metallic stent implantation of the internal carotid artery

International Nuclear Information System (INIS)

Yoon, Man Won; Kim, Hyeon Chul; Kim, Jae Kyu; Seo, Jeong Jin; Jeong, Gwang Woo; Kang, Heoung Keun

1999-01-01

To evaluate the usefulness of CT angiography in patients with implantation of metallic stent for stenosed internal carotid artery. Seven patients with atherosclerotic stenosis of the internal carotid artery underwent metallic stent implantation. All were male and their ages ranged from 36 to 69 years. A total of seven stents were placed in the internal carotid artery in five patients and in the carotid bifurcation in two. Spiral CT scans were obtained and CT angiographic images were reconstructed using MPR or curved MPR techniques at a workstation. The interval between CT and conventional angiography did not exceed six days except in one patient, in whom it was 61days. CT and conventional angiography were compared for stent position with respect to the carotid bifurcation, stent deformation, intraluminal filling defect, and luminal caliber and outflow. Luminal patency of the implanted stent was measured according to NASCET(North American Symptomatic Carotid Endarterectomy Trial) criteria, and statistically processed (p>.05). The presence or absence of intrastent thrombus and vascular wall calcification was determined using axial source images. In all patients, CT angiographic findings matched those obtained by conventional angiography. Complications such as migration or deformation of an implanted stent, intraluminal filling defect, change of luminal caliber or outflow of implanted stent were not observed in any patient. In two studies in which Wilcoxon signed rank test was used, degree of stent expansion correlated closely(p=0.237). Axial source images showed that in no patient was an intrastent thrombus present, though in five, vascular wall calcification of internal carotid arteries outside the stent was noted. CT angiography is useful for the assessment of positional change, occlusion, and luminal patency of a stent-implanted internal carotid artery

Accessory left gastric artery: angiographic anatomy

Energy Technology Data Exchange (ETDEWEB)

Lee, Kang Soo; Lim, Hyung Guhn; Kim, Hong Soo; Jeon, Doo Sung [Presbyterian Medical Center, Chunju (Korea, Republic of); Chung, Jin Wook; Park, Jae Hyung [College of Medicine and the Institute of Radiation Medicine, Seoul National University, Seoul (Korea, Republic of); Song, Soon Young [Myongji Hospital, College of Medicine, Kwandong University, Seoul (Korea, Republic of)

2000-09-01

To evaluate the angiographic anatomy of the accessory left gastric artery (accLGA). We evaluated the angiographic findings of the accLGA in 50 patients (Angiostar; Siemens, Erlangen, Germany). Performing celiac and selective angiography in 50 and 34 patients, respectively. By means of celiac angiography, (1) site of origin, (2) anatomical course, (3) diameter, (4) degree of tortuosity, and (5) distal tapering were evaluated, while selective angiography was used to determine (1) arterial branching, (2) area of blood supply, and (3) patterns of gastric wall stain. Celiac angiography showed that the accLGA arose from the left hepatic artery (LHA) in 45 cases (90%) and from the proper hepatic artery in five (10%). If the accLGA arose from the LHA, its origin entirely depended on the branching pattern of the latter. It always arose from the lateral branch of the LHA furthest to the left and uppermost, and proximal to its umbilical point. The most common anatomical course of the accLGA, seen in 27 cases (54%), was between the S2 and S3 segmental branch. The diameter and degree of tortuosity of the accLGA were similar to those of adjacent intrahepatic branches in 21 (42%) and 33 cases (66%), respectively. The degree of tapering was less than that of adjacent intrahepatic vessel in 28 (56%). Selective angiography demonstrated esophageal branching of the acc LGA in 27 cases (79%), inferior phrenic arterial branching in three (9%), a mediastinal branch in one (3%), and hypervascularity of the lung in one (3%). In 15 cases (44%), bifurcation of the accLGA was recognized. The vascular territory of the accLGA was the gastric fundus together with the distal esophagus in 21 cases (62%), mainly the gastric fundus in six (18%), and mainly the distal esophagus in four (12%). The pattern of gastric mucosal stain was curvilinear wall in 31 cases (91%) and nodular in three (9%). A knowledge of the angiographic anatomy of the accLGA facilitates accurate recognition of this artery on

64-Row multidetector CT virtual hysterosalpingography. Findings in 2500 patients

International Nuclear Information System (INIS)

Carrascosa, Patricia; Capunay, Carlos; Baronio, Mariano; Vallejos, Javier; Papier, Sergio; Carrascosa, Jorge

2011-01-01

Objective. To depict typical features of virtual hysterosalpingography (VHSG) in infertile patients. Material and methods: 2500 VHSG performed using a 64-row MOCT were evaluated. Results: Cervical abnormalities visualized corresponded to parietal irregularities (21%); thickened folds (9%); polyps (11%); diverticula (5%); cervical strictures (8%), and synechiae (1.5%). At the level of uterine cavity, polyps (44%); submucous myomas (8%); intramural and subserosal fibroids (11%); synechiae (10%); malformations (10%); adenomyosis (4%), and cesarean section scar (3%). Unilateral hydrosalpinx (7%) and bilateral hydrosalpinx (2%). Tubal obstruction was reported in 6% of cases. The average radiation dose was 0.94 mSv. Eighty-four percent of the patients reported mild pain or no postoperative discomfort. Conclusions: The virtual hysterosalpingography allowed a proper assessment of the internal genital organs, providing useful diagnostic information on infertility and other gynecological disorders. It constitutes a virtually painless, low-dose radiation technique, besides being well tolerated by patients

Suicide on Death Row.

Science.gov (United States)

Tartaro, Christine; Lester, David

2016-11-01

Despite the level of supervision of inmates on death row, their suicide rate is higher than both the male prison population in the United States and the population of males over the age of 14 in free society. This study presents suicide data for death row inmates from 1978 through 2010. For the years 1978 through 2010, suicide rates on death row were higher than that for the general population of males over the age of 15 and for state prisons for all but 2 years. © 2016 American Academy of Forensic Sciences.

A simple digital subtraction angiographic instrument

International Nuclear Information System (INIS)

Ando, Hiroshi; Kobayashi, Tsuyoshi; Imai, Yutaka; Yanagishita, Akira

1983-01-01

A digital subtraction angiographic instrument was manufactured using a conventional x-ray TV for gastrointestinal series and a computer for processing of nuclear medical data. The results of visualization of the aorta and its primary branches were reviewed with demonstrable cases. (Chiba, N.)

Effect of transcatheter arterial embolization according to angiographic findings in hepatocellular carcinoma

International Nuclear Information System (INIS)

Wang, Chi Hyung; Shim, Hyung Jin; Lee, Jong Ik; Yu, Hyun; Kim, Young Goo; Lee, Jong Beum; Kim, Kun Sang

1994-01-01

The purpose of this study is to assess the effect of Transcatheter Arterial Embolization(TAE) according to angiographic findings in hepatocellular carcinoma. We retrospectively reviewed 50 cases who received TAE for unresectable hepatocellular carcinoma. We analyzed the angiographic findings which were correlated with the effect of TAE. The common angiographic findings of the hepatocellular carcinoma were tumor staining, neo vascularity and enlargement of feeding artery. These angiographic findings were classified into grade 0, +1, +2. Effect of TAE were classified into five patterns; good response, partial response, minimal response, no response and more aggravation. In grading of tumor staining, among 50 cases, the grade 0, +1, +2 were seen in 1 case(2%), 14 cases(28%), 35 cases(70%) each. In grading of enlargement of feeding artery, the grade 0, +1, +2 were seen in 7 cases(14%), 19 cases(38%), 24 cases(48%) each. In grading of neo vascularity, the grade 0, +1, +2 were seen in 6 cases(12%), 15 cases(30%), 29 cases(58%) each. This study showed that the higher grade of angiographic finding, the better effect of TAE. A statistically significant difference was found (P<0.005). But the TAE was not effective in some cases (the maximum diameter of mass is over 10cm, portal vein thrombosis or arteriovenous shunt) in spite of high grade. We believe that these angiographic findings (tumor staining, enlargement of feeding artery, neo vascularity) are one of important indices for anticipating the effect of TAE in patients with unresectable hepatocellular carcinoma

Does double-row rotator cuff repair improve functional outcome of patients compared with single-row technique? A systematic review.

Science.gov (United States)

DeHaan, Alexander M; Axelrad, Thomas W; Kaye, Elizabeth; Silvestri, Lorenzo; Puskas, Brian; Foster, Timothy E

2012-05-01

The advantage of single-row versus double-row arthroscopic rotator cuff repair techniques has been a controversial issue in sports medicine and shoulder surgery. There is biomechanical evidence that double-row techniques are superior to single-row techniques; however, there is no clinical evidence that the double-row technique provides an improved functional outcome. When compared with single-row rotator cuff repair, double-row fixation, although biomechanically superior, has no clinical benefit with respect to retear rate or improved functional outcome. Systematic review. The authors reviewed prospective studies of level I or II clinical evidence that compared the efficacy of single- and double-row rotator cuff repairs. Functional outcome scores included the American Shoulder and Elbow Surgeons (ASES) shoulder scale, the Constant shoulder score, and the University of California, Los Angeles (UCLA) shoulder rating scale. Radiographic failures and complications were also analyzed. A test of heterogeneity for patient demographics was also performed to determine if there were differences in the patient profiles across the included studies. Seven studies fulfilled our inclusion criteria. The test of heterogeneity across these studies showed no differences. The functional ASES, Constant, and UCLA outcome scores revealed no difference between single- and double-row rotator cuff repairs. The total retear rate, which included both complete and partial retears, was 43.1% for the single-row repair and 27.2% for the double-row repair (P = .057), representing a trend toward higher failures in the single-row group. Through a comprehensive literature search and meta-analysis of current arthroscopic rotator cuff repairs, we found that the single-row repairs did not differ from the double-row repairs in functional outcome scores. The double-row repairs revealed a trend toward a lower radiographic proven retear rate, although the data did not reach statistical significance. There

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.

A biomechanical comparison of 2 technical variations of double-row rotator cuff fixation: the importance of medial row knots.

Science.gov (United States)

Busfield, Benjamin T; Glousman, Ronald E; McGarry, Michelle H; Tibone, James E; Lee, Thay Q

2008-05-01

Previous studies have shown comparable biomechanical properties of double-row fixation versus double-row fixation with a knotless lateral row. SutureBridge is a construct that secures the cuff with medial row mattress suture anchors and knotless lateral row fixation of the medial suture ends. Recent completely knotless constructs may lead to lesser clinical outcomes if the construct properties are compromised from lack of suture knots. A completely knotless construct without medial row knots will compromise the biomechanical properties in both cyclic and failure-testing parameters. Controlled laboratory study. Six matched pairs of cadaveric shoulders were randomized to 2 groups of double row fixation with SutureBridge: group 1 with medial row knots, and group 2 without medial row knots. The specimens were placed in a materials test system at 30 degrees of abduction. Cyclic testing to 180 N at 1 mm/sec for 30 cycles was performed, followed by tensile testing to failure at 1 mm/sec. Data included cyclic and failure data from the materials test system and gap data using a video digitizing system. All data from paired specimens were compared using paired Student t tests. Group 1 had a statistically significant difference (P row failure, whereas all group 1 specimens failed at the clamp. Although lateral row knotless fixation has been shown not to sacrifice structural integrity of this construct, the addition of a knotless medial row compromises the construct leading to greater gapping and failure at lower loads. This may raise concerns regarding recently marketed completely knotless double row constructs.

CT classification and clinical prognosis of cerebral infarction in the area of middle cerebral artery

International Nuclear Information System (INIS)

Konno, Jyoji

1983-01-01

Computerized tomographies (CT) were repeatedly scanned on 70 patients with cerebral infarction in the middle cerebral artery. Low density area (LDA) was measured with HounFsfield's Unit (HU) and studied on the progressive changes. Classification of LDA was attempted and studied on correlation with mass effect, contrast enhancement, angiographical findings, clinical symptoms and prognosis. It was considered that important points of diagnosis of cerebral infarction were timing of examination of CT and determination of LDA with HUF. It was also thought that CT classification of LDA was usefull to estimate prognosis of the patients with cerebral infarction. (author)

Temporal resolution measurement of 128-slice dual source and 320-row area detector computed tomography scanners in helical acquisition mode using the impulse method.

Science.gov (United States)

Hara, Takanori; Urikura, Atsushi; Ichikawa, Katsuhiro; Hoshino, Takashi; Nishimaru, Eiji; Niwa, Shinji

2016-04-01

To analyse the temporal resolution (TR) of modern computed tomography (CT) scanners using the impulse method, and assess the actual maximum TR at respective helical acquisition modes. To assess the actual TR of helical acquisition modes of a 128-slice dual source CT (DSCT) scanner and a 320-row area detector CT (ADCT) scanner, we assessed the TRs of various acquisition combinations of a pitch factor (P) and gantry rotation time (R). The TR of the helical acquisition modes for the 128-slice DSCT scanner continuously improved with a shorter gantry rotation time and greater pitch factor. However, for the 320-row ADCT scanner, the TR with a pitch factor of pitch factor of >1.0, it was approximately one half of the gantry rotation time. The maximum TR values of single- and dual-source helical acquisition modes for the 128-slice DSCT scanner were 0.138 (R/P=0.285/1.5) and 0.074s (R/P=0.285/3.2), and the maximum TR values of the 64×0.5- and 160×0.5-mm detector configurations of the helical acquisition modes for the 320-row ADCT scanner were 0.120 (R/P=0.275/1.375) and 0.195s (R/P=0.3/0.6), respectively. Because the TR of a CT scanner is not accurately depicted in the specifications of the individual scanner, appropriate acquisition conditions should be determined based on the actual TR measurement. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Interventional spinal procedures guided and controlled by a 3D rotational angiographic unit.

Science.gov (United States)

Pedicelli, Alessandro; Verdolotti, Tommaso; Pompucci, Angelo; Desiderio, Flora; D'Argento, Francesco; Colosimo, Cesare; Bonomo, Lorenzo

2011-12-01

The aim of this paper is to demonstrate the usefulness of 2D multiplanar reformatting images (MPR) obtained from rotational acquisitions with cone-beam computed tomography technology during percutaneous extra-vascular spinal procedures performed in the angiography suite. We used a 3D rotational angiographic unit with a flat panel detector. MPR images were obtained from a rotational acquisition of 8 s (240 images at 30 fps), tube rotation of 180° and after post-processing of 5 s by a local work-station. Multislice CT (MSCT) is the best guidance system for spinal approaches permitting direct tomographic visualization of each spinal structure. Many operators, however, are trained with fluoroscopy, it is less expensive, allows real-time guidance, and in many centers the angiography suite is more frequently available for percutaneous procedures. We present our 6-year experience in fluoroscopy-guided spinal procedures, which were performed under different conditions using MPR images. We illustrate cases of vertebroplasty, epidural injections, selective foraminal nerve root block, facet block, percutaneous treatment of disc herniation and spine biopsy, all performed with the help of MPR images for guidance and control in the event of difficult or anatomically complex access. The integrated use of "CT-like" MPR images allows the execution of spinal procedures under fluoroscopy guidance alone in all cases of dorso-lumbar access, with evident limitation of risks and complications, and without need for recourse to MSCT guidance, thus eliminating CT-room time (often bearing high diagnostic charges), and avoiding organizational problems for procedures that need, for example, combined use of a C-arm in the CT room.

Interventional spinal procedures guided and controlled by a 3D rotational angiographic unit

International Nuclear Information System (INIS)

Pedicelli, Alessandro; Verdolotti, Tommaso; Desiderio, Flora; D'Argento, Francesco; Colosimo, Cesare; Bonomo, Lorenzo; Pompucci, Angelo

2011-01-01

The aim of this paper is to demonstrate the usefulness of 2D multiplanar reformatting images (MPR) obtained from rotational acquisitions with cone-beam computed tomography technology during percutaneous extra-vascular spinal procedures performed in the angiography suite. We used a 3D rotational angiographic unit with a flat panel detector. MPR images were obtained from a rotational acquisition of 8 s (240 images at 30 fps), tube rotation of 180 and after post-processing of 5 s by a local work-station. Multislice CT (MSCT) is the best guidance system for spinal approaches permitting direct tomographic visualization of each spinal structure. Many operators, however, are trained with fluoroscopy, it is less expensive, allows real-time guidance, and in many centers the angiography suite is more frequently available for percutaneous procedures. We present our 6-year experience in fluoroscopy-guided spinal procedures, which were performed under different conditions using MPR images. We illustrate cases of vertebroplasty, epidural injections, selective foraminal nerve root block, facet block, percutaneous treatment of disc herniation and spine biopsy, all performed with the help of MPR images for guidance and control in the event of difficult or anatomically complex access. The integrated use of ''CT-like'' MPR images allows the execution of spinal procedures under fluoroscopy guidance alone in all cases of dorso-lumbar access, with evident limitation of risks and complications, and without need for recourse to MSCT guidance, thus eliminating CT-room time (often bearing high diagnostic charges), and avoiding organizational problems for procedures that need, for example, combined use of a C-arm in the CT room. (orig.)

Interventional spinal procedures guided and controlled by a 3D rotational angiographic unit

Energy Technology Data Exchange (ETDEWEB)

Pedicelli, Alessandro; Verdolotti, Tommaso; Desiderio, Flora; D' Argento, Francesco; Colosimo, Cesare; Bonomo, Lorenzo [Catholic University of Rome, A. Gemelli Hospital, Department of Bioimaging and Radiological Sciences, Rome (Italy); Pompucci, Angelo [Catholic University of Rome, A. Gemelli Hospital, Department of Neurotraumatology, Rome (Italy)

2011-12-15

The aim of this paper is to demonstrate the usefulness of 2D multiplanar reformatting images (MPR) obtained from rotational acquisitions with cone-beam computed tomography technology during percutaneous extra-vascular spinal procedures performed in the angiography suite. We used a 3D rotational angiographic unit with a flat panel detector. MPR images were obtained from a rotational acquisition of 8 s (240 images at 30 fps), tube rotation of 180 and after post-processing of 5 s by a local work-station. Multislice CT (MSCT) is the best guidance system for spinal approaches permitting direct tomographic visualization of each spinal structure. Many operators, however, are trained with fluoroscopy, it is less expensive, allows real-time guidance, and in many centers the angiography suite is more frequently available for percutaneous procedures. We present our 6-year experience in fluoroscopy-guided spinal procedures, which were performed under different conditions using MPR images. We illustrate cases of vertebroplasty, epidural injections, selective foraminal nerve root block, facet block, percutaneous treatment of disc herniation and spine biopsy, all performed with the help of MPR images for guidance and control in the event of difficult or anatomically complex access. The integrated use of ''CT-like'' MPR images allows the execution of spinal procedures under fluoroscopy guidance alone in all cases of dorso-lumbar access, with evident limitation of risks and complications, and without need for recourse to MSCT guidance, thus eliminating CT-room time (often bearing high diagnostic charges), and avoiding organizational problems for procedures that need, for example, combined use of a C-arm in the CT room. (orig.)

Traumatic thoracic injury: the role of Multidetector-row CT

International Nuclear Information System (INIS)

Lim, Se Kyong; Shin, Kyung Sook; Kim, Ha Young; Sung, Jae Kyu; Jung, Hyun Yong; Noh, Seong Moo; Song, Kyu Sang; Cho, June Sik

2006-01-01

Hyperplastic polyps are common gastric lesions that are characterized by nonneoplastic epithelial hyperplasia. However, to our knowledge, there are no reports of a hyperplastic polyp arising from an endoscopic mucosectomy site of early gastric cancer. We describe the CT findings with a histopathology correlation in a case of a hyperplastic polyp arising from a mucosectomy site that mimicked polypoid gastric cancer

Traumatic thoracic injury: the role of Multidetector-row CT

Energy Technology Data Exchange (ETDEWEB)

Lim, Se Kyong; Shin, Kyung Sook; Kim, Ha Young; Sung, Jae Kyu; Jung, Hyun Yong; Noh, Seong Moo; Song, Kyu Sang; Cho, June Sik [Chungnam National University School of Medicine, Daejeon (Korea, Republic of)

2006-05-15

Hyperplastic polyps are common gastric lesions that are characterized by nonneoplastic epithelial hyperplasia. However, to our knowledge, there are no reports of a hyperplastic polyp arising from an endoscopic mucosectomy site of early gastric cancer. We describe the CT findings with a histopathology correlation in a case of a hyperplastic polyp arising from a mucosectomy site that mimicked polypoid gastric cancer.

Clinical and angiographic outcomes after intracoronary bare-metal stenting.

Directory of Open Access Journals (Sweden)

I-Chang Hsieh

Full Text Available BACKGROUND: Data from a large patient population regarding very long-term outcomes after BMS implantation are inadequate. This study aimed to evaluate the very long-term (8-17 years clinical and long-term (3-5 years angiographic outcomes after intracoronary bare-metal stenting (BMS. METHODS AND RESULTS: From the Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions (CAPTAIN registry, a total of 2391 patients with 2966 lesions treated with 3190 BMSs between November 1995 and May 2004 were evaluated. In total, 1898 patients with 2364 lesions, and 699 patients with 861 lesions underwent 6-month and 3- to 5- year angiographic follow-up, respectively. During a mean follow-up period of 149 ± 51 months, 18.6% of the patients died (including 10.8% due to cardiac death, 6.1% developed reinfarction, 16.2% had target lesion revascularization (including 81% of the patients within the first year, 14.5% underwent new lesion stenting (including 72% of the patients after 3 years, 2.4% underwent coronary bypass surgery, and 1.6% had definite stent thrombosis. The overall cardiovascular event-free survival rate was 58.5%. The 6-month angiographic study indicated a 20% restenosis rate. The minimal luminal diameter increased from 0.65 ± 0.44 mm to 3.02 ± 0.46 mm immediately after stenting, decreased to 2.06 ± 0.77 mm at the 6-month follow-up, and increased to 2.27 ± 0.68 mm at the 3- to 5-year follow-up. CONCLUSIONS: This study provides clinical and angiographic results from a large population of patients who underwent BMS implantations after a long-term follow-up period (149 ± 51 months. The progression of coronary atherosclerosis developed over time, and presented with new lesion required stent implantation. The follow-up angiographic findings reconfirmed the late and sustained improvement in luminal diameter between 6 months and 3-5 years.

Mechanical performance of aquatic rowing and flying.

Science.gov (United States)

Walker, J A; Westneat, M W

2000-09-22

Aquatic flight, performed by rowing or flapping fins, wings or limbs, is a primary locomotor mechanism for many animals. We used a computer simulation to compare the mechanical performance of rowing and flapping appendages across a range of speeds. Flapping appendages proved to be more mechanically efficient than rowing appendages at all swimming speeds, suggesting that animals that frequently engage in locomotor behaviours that require energy conservation should employ a flapping stroke. The lower efficiency of rowing appendages across all speeds begs the question of why rowing occurs at all. One answer lies in the ability of rowing fins to generate more thrust than flapping fins during the power stroke. Large forces are necessary for manoeuvring behaviours such as accelerations, turning and braking, which suggests that rowing should be found in slow-swimming animals that frequently manoeuvre. The predictions of the model are supported by observed patterns of behavioural variation among rowing and flapping vertebrates.

Multislice computed tomography: angiographic emulation versus standard assessment for detection of coronary stenoses

Energy Technology Data Exchange (ETDEWEB)

Schnapauff, Dirk; Hamm, Bernd; Dewey, Marc [Humboldt-Universitaet zu Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, P.O. Box 10098, Berlin (Germany); Duebel, Hans-Peter; Baumann, Gert [Charite - Universitaetsmedizin Berlin, Department of Cardiology, Berlin (Germany); Scholze, Juergen [Charite - Universitaetsmedizin Berlin, Charite Outpatient Centre, Berlin (Germany)

2007-07-15

The present study investigated angiographic emulation of multislice computed tomography (MSCT) (catheter-like visualization) as an alternative approach of analyzing and visualizing findings in comparison with standard assessment. Thirty patients (120 coronary arteries) were randomly selected from 90 prospectively investigated patients with suspected coronary artery disease who underwent MSCT (16-slice scanner, 0.5 mm collimation, 400 ms rotation time) prior to conventional coronary angiography for comparison of both approaches. Sensitivity and specificity of angiographic emulation [81% (26/32) and 93% (82/88)] were not significantly different from those of standard assessment [88% (28/32) and 99% (87/88)], while the per-case analysis time was significantly shorter for angiographic emulation than for standard assessment (3.4 {+-} 1.5 vs 7.0 {+-} 2.5 min, P < 0.001). Both interventional and referring cardiologists preferred angiographic emulation over standard curved multiplanar reformations of MSCT coronary angiography for illustration, mainly because of improved overall lucidity and depiction of sidebranches (P < 0.001). In conclusion, angiographic emulation of MSCT reduces analysis time, yields a diagnostic accuracy comparable to that of standard assessment, and is preferred by cardiologists for visualization of results. (orig.)

Tracheal compression due to an elongated aortic arch in patients with congenital heart disease: evaluation using multidetector-row CT

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Noriko; Hayabuchi, Yasunobu; Inoue, Miki; Sakata, Miho; Nabo, Manal Mohamed Helmy; Nakagawa, Ryuji; Saijo, Takahiko; Kagami, Shoji [University of Tokushima, Department of Pediatrics, Tokushima (Japan)

2009-10-15

The airway can become obstructed as a result of compression by an elongated aortic arch. In this study we evaluated tracheal compression using multidetector-row CT in patients with congenital heart disease and an elongated aortic arch. The trachea was measured at the level of the aortic arch in 205 children and young adults and then the severity of tracheal compression was determined by measuring the tracheal diameter ratio (short axis diameter/long axis diameter). Patients were divided as follows: group I (normal aortic arch; n=166), group II (transversely running aortic arch; n=22), and group III (elongated aortic arch; n=17). From the viewpoint of the relationship of the great arteries, group II had D-malposition, and group III had L-malposition. Age, height, weight and body surface area were significantly correlated with the short and long axis diameter in group I. There was a negative correlation between tracheal diameter ratio and the physical size parameters. The tracheal diameter ratio in group III was 0.50{+-}0.13, which was significantly lower than in groups I and II (P<0.01 and 0.05, respectively). Even apparently asymptomatic patients with an elongated aortic arch can have tracheal compression. An elongated aortic arch may be a useful predictor of tracheal compression. (orig.)

[Chronic pancreatitis: which is the role of 320-row CT for the staging?].

Science.gov (United States)

Stabile Ianora, Amato Antonio; Rubini, Giuseppe; Lorusso, Filomenamila; Ambriola, Angela; Rella, Leonarda; Di Crescenzo, Vincenzo; Moschetta, Marco

2013-01-01

The purpose of this study was to evaluate the diagnostic potential of multi-planar and volumetric reconstructions obtained from isotropic data by using 16-slice computed tomography (CT) in the diagnosis and staging of chronic pancreatitis. In a group of 42 patients CT images were evaluated searching for alterations in morphology and structure of the pancreas, alterations of the Wirsung duct, dilatation of the bile ducts, fluid collections, and vascular involvement of the digestive tract. The disease was then staged in mild, moderate and severe and correlated with the clinical staging. CT allowed the recognition of chronic pancreatitis in all cases. The staging was correct in 25/42 patients, with an accuracy rate of 59.5%. In the staging of moderate and severe forms, CT correlation with clinical and laboratory data was valid, but in mild forms it appeared less significant. Multi-detector CT is accurate in the recognition of moderate, advanced forms of chronic pancreatitis and in the identification of its complications, while it is poorly correlated with the clinical staging in mild forms of the disease.

Three-dimensional evaluation of cyclic displacement in single-row and double-row rotator cuff reconstructions under static external rotation.

Science.gov (United States)

Lorbach, Olaf; Kieb, Matthias; Raber, Florian; Busch, Lüder C; Kohn, Dieter M; Pape, Dietrich

2013-01-01

The double-row suture bridge repair was recently introduced and has demonstrated superior biomechanical results and higher yield load compared with the traditional double-row technique. It therefore seemed reasonable to compare this second generation of double-row constructs to the modified single-row double mattress reconstruction. The repair technique, initial tear size, and tendon subregion will have a significant effect on 3-dimensional (3D) cyclic displacement under additional static external rotation of a modified single-row compared with a double-row rotator cuff repair. Controlled laboratory study. Rotator cuff tears (small to medium: 25 mm; medium to large: 35 mm) were created in 24 human cadaveric shoulders. Rotator cuff repairs were performed as modified single-row or double-row repairs, and cyclic loading (10-60 N, 10-100 N) was applied under 20° of external rotation. Radiostereometric analysis was used to calculate cyclic displacement in the anteroposterior (x), craniocaudal (y), and mediolateral (z) planes with a focus on the repair constructs and the initial tear size. Moreover, differences in cyclic displacement of the anterior compared with the posterior tendon subregions were calculated. Significantly lower cyclic displacement was seen in small to medium tears for the single-row compared with double-row repair at 60 and 100 N in the x plane (P = .001) and y plane (P = .001). The results were similar in medium to large tears at 100 N in the x plane (P = .004). Comparison of 25-mm versus 35-mm tears did not show any statistically significant differences for the single-row repairs. In the double-row repairs, lower gap formation was found for the 35-mm tears (P ≤ .05). Comparison of the anterior versus posterior tendon subregions revealed a trend toward higher anterior gap formation, although this was statistically not significant. The tested single-row reconstruction achieved superior results in 3D cyclic displacement to the tested double-row

Latest techniques in head and neck CT angiography

International Nuclear Information System (INIS)

Schuknecht, B.

2004-01-01

Continuous evolution of multi row CT is increasingly making CT angiography a viable imaging modality for assessment of the supraaortic and intracranial vessels as an anatomically and functionally coherent vascular system. Extended non-invasive examinations with reduced contrast volume have become feasible with the availability of 16 and 64 row MDCT scanners. Prerequisites to obtain high resolution CT angiographies of the head and neck vessels with superior detail include the administration of low contrast volume, high contrast density (400 mg I/ml) contrast media, adequate timing and data acquisition, optimal flow rate (4 ml/s) and saline flushing. Non-invasiveness, delineation of vessel calcification, virtual independence from hemodynamic conditions, and the ability to provide quantification without needing to correct for magnification are all attributes that favour CT angiography over digital subtraction angiography and to some extent even magnetic resonance angiography as an alternative non-invasive technique. CT angiography is established as a modality of choice for the assessment of patients with acute stroke and chronic steno-occlusive disease. CT angiography may indicate the presence of extra- or intracranial acute vessel occlusion and dissection, predisposing atherosclerotic steno-occlusive disease and thus indicate thrombo-embolism or local appositional thrombosis as the principle pathogenic factor. CT angiography is used to assess anatomy, and to depict the presence, location and extent of calcified and non-calcified plaque as a cause of high grade stenosis. Despite relatively limited sensitivity CT angiography is indicated for suspected or confirmed aneurysms that demand further verification of their presence, geometry, or relationship to parent artery branches and osseous anatomic landmarks. Low volume high density contrast media have substantially increased the ability of CT angiography to depict small aneurysms, small branches, and collateral vessels

Prosodic Function Row in Persian Poetry

Directory of Open Access Journals (Sweden)

Majid Mansouri

2017-04-01

The main reason for the emergence of rows in Persian poetry is its prosodic function that has already been paid less. I just found something in the book Ghosn al-ban which the author had some similar view to the row. In this study, we made our attempt to show another reason for the entry and spread of the row in Persian poetry by means of a new approach. It should also be noted that in these lines to avoid as much as possible the repetitive and stereotyped points regarding the row.

Spontaneous regression of cerebral arteriovenous malformations: clinical and angiographic analysis with review of the literature

International Nuclear Information System (INIS)

Lee, S.K.; Vilela, P.; Willinsky, R.; TerBrugge, K.G.

2002-01-01

Spontaneous regression of cerebral arteriovenous malformation (AVM) is rare and poorly understood. We reviewed the clinical and angiographic findings in patients who had spontaneous regression of cerebral AVMs to determine whether common features were present. The clinical and angiographic findings of four cases from our series and 29 cases from the literature were retrospectively reviewed. The clinical and angiographic features analyzed were: age at diagnosis, initial presentation, venous drainage pattern, number of draining veins, location of the AVM, number of arterial feeders, clinical events during the interval period to thrombosis, and interval period to spontaneous thrombosis. Common clinical and angiographic features of spontaneous regression of cerebral AVMs are: intracranial hemorrhage as an initial presentation, small AVMs, and a single draining vein. Spontaneous regression of cerebral AVMs can not be predicted by clinical or angiographic features, therefore it should not be considered as an option in cerebral AVM management, despite its proven occurrence. (orig.)

Angiographic and hemodynamic evaluation of the mesoatrial shunt in patients with Budd-Chiari syndrome and inferior vena caval obstruction

International Nuclear Information System (INIS)

Redmond, P.L.; Kadir, S.; Cameron, J.L.; Kaufman, S.L.; White, R.I. Jr.

1986-01-01

Obstruction of the inferior vena cava (IVC) is not uncommon in patients with the Budd-Chiari syndrome. The caval obstruction may be due to thrombus or compression by an enlarged caudate lobe. Conventional portosystemic shunts are not possible in the presence of an obstructed IVC; the mesoatrial shunt is indicated in these patients. Between 1973 and 1986, the authors studied 13 patients (ten female, three male) with Budd-Chiari syndrome and IVC obstruction in whom mesoatrial shunts were subsequently constructed. Polycythemia rubra vera was the most common predisposing condition. Preoperative evaluation included US, scintigraphy, CT, and angiography (hepatic arteriography, hepatic venography and pressure measurements, inferior vena cavography, arterial portography). Postoperatively shunts were assessed angiographically and hemodynamically, and several patients underwent CT. The shunts were catheterized via a brachial or femoral venous approach, which allowed pressures along the shunt from the superior mesenteric vein to the right atrium to be measured. The mesoatrial shunt is a relatively new procedure which is indicated in patients with the Budd-Chiari syndrome complicated by IVC obstruction. Shunt patency may be demonstrated arteriographically or with CT, but hemodynamic evaluation with measurement of pressure gradients is required to assess shunt function

Optimization of Inter-Row Spacing and Nitrogen Rate for the Application of Vision Guided Inter-Row weeding in Organic Spring Cereals

DEFF Research Database (Denmark)

Melander, Bo; Green, O.; Znova, L.

2016-01-01

-row spacing and nitrogen rate on weed and crop growth. Results are reported from two years field experiments with spring barley and spring wheat. It was aimed to maintain a constant seed rate for all five row spacing studied (12.5, 15, 20, 25 and 30 cm), which gave a higher crop density in the rows...... with increasing row spacing. A denser intra-row crop stand would improve the suppression of surviving intra-row weeds and partly compensate for the more weed growth that wider row spacing would cause by allowing more light penetration into the crop canopy. It was found that maintaining the seed rate when...

A novel method for the angiographic estimation of the percentage of spleen volume embolized during partial splenic embolization

International Nuclear Information System (INIS)

Ou, Ming-Ching; Chuang, Ming-Tsung; Lin, Xi-Zhang; Tsai, Hong-Ming; Chen, Shu-Yuan; Liu, Yi-Sheng

2013-01-01

Purpose: To evaluate the efficacy of estimating the volume of spleen embolized in partial splenic embolization (PSE) by measuring the diameters of the splenic artery and its branches. Materials and methods: A total of 43 liver cirrhosis patients (mean age, 62.19 ± 9.65 years) with thrombocytopenia were included. Among these, 24 patients underwent a follow-up CT scan which showed a correlation between angiographic estimation and measured embolized splenic volume. Estimated splenic embolization volume was calculated by a method based on diameters of the splenic artery and its branches. The diameters of each of the splenic arteries and branches were measured via 2D angiographic images. Embolization was performed with gelatin sponges. Patients underwent follow-up with serial measurement of blood counts and liver function tests. The actual volume of embolized spleen was determined by computed tomography (CT) measuring the volumes of embolized and non-embolized spleen two months after PSE. Results: PSE was performed without immediate major complications. The mean WBC count significantly increased from 3.81 ± 1.69 × 10 3 /mm 3 before PSE to 8.56 ± 3.14 × 10 3 /mm 3 at 1 week after PSE (P < 0.001). Mean platelet count significantly increased from 62.00 ± 22.62 × 10 3 /mm 3 before PSE to 95.40 ± 46.29 × 10 3 /mm 3 1 week after PSE (P < 0.001). The measured embolization ratio was positively correlated with estimated embolization ratio (Spearman's rho [ρ] = 0.687, P < 0.001). The mean difference between the actual embolization ratio and the estimated embolization ratio was 16.16 ± 8.96%. Conclusions: The method provides a simple method to quantitatively estimate embolized splenic volume with a correlation of measured embolization ratio to estimated embolization ratio of Spearman's ρ = 0.687

Single-row modified mason-allen versus double-row arthroscopic rotator cuff repair: a biomechanical and surface area comparison.

Science.gov (United States)

Nelson, Cory O; Sileo, Michael J; Grossman, Mark G; Serra-Hsu, Frederick

2008-08-01

The purpose of this study was to compare the time-zero biomechanical strength and the surface area of repair between a single-row modified Mason-Allen rotator cuff repair and a double-row arthroscopic repair. Six matched pairs of sheep infraspinatus tendons were repaired by both techniques. Pressure-sensitive film was used to measure the surface area of repair for each configuration. Specimens were biomechanically tested with cyclic loading from 20 N to 30 N for 20 cycles and were loaded to failure at a rate of 1 mm/s. Failure was defined at 5 mm of gap formation. Double-row suture anchor fixation restored a mean surface area of 258.23 +/- 69.7 mm(2) versus 148.08 +/- 75.5 mm(2) for single-row fixation, a 74% increase (P = .025). Both repairs had statistically similar time-zero biomechanics. There was no statistical difference in peak-to-peak displacement or elongation during cyclic loading. Single-row fixation showed a higher mean load to failure (110.26 +/- 26.4 N) than double-row fixation (108.93 +/- 21.8 N). This was not statistically significant (P = .932). All specimens failed at the suture-tendon interface. Double-row suture anchor fixation restores a greater percentage of the anatomic footprint when compared with a single-row Mason-Allen technique. The time-zero biomechanical strength was not significantly different between the 2 study groups. This study suggests that the 2 factors are independent of each other. Surface area and biomechanical strength of fixation are 2 independent factors in the outcome of rotator cuff repair. Maximizing both factors may increase the likelihood of complete tendon-bone healing and ultimately improve clinical outcomes. For smaller tears, a single-row modified Mason-Allen suture technique may provide sufficient strength, but for large amenable tears, a double row can provide both strength and increased surface area for healing.

Coronary computed tomography angiography with 320-row detector and using the AIDR-3D: initial experience

International Nuclear Information System (INIS)

Sasdelli Neto, Roberto; Nomura, Cesar Higa; Macedo, Ana Carolina Sandoval; Bianco, Danilo Perussi; Kay, Fernando Uliana; Szarf, Gilberto; Teles, Gustavo Borges da Silva; Shoji, Hamilton; Santana Netto, Pedro Vieira; Passos, Rodrigo Bastos Duarte; Chate, Rodrigo Caruso; Ishikawa, Walther Yoshiharu; Lima, Joao Paulo Bacellar Costa; Rocha, Marcelo Assis; Marcos, Vinicius Neves; Funari, Marcelo Buarque de Gusmao; Failla, Bruna Bonaventura

2013-01-01

Coronary computed tomography angiography (coronary CTA) is a powerful non-invasive imaging method to evaluate coronary artery disease. Nowadays, coronary CTA estimated effective radiation dose can be dramatically reduced using state-of-the-art scanners, such as 320-row detector CT (320-CT), without changing coronary CTA diagnostic accuracy. To optimize and further reduce the radiation dose, new iterative reconstruction algorithms were released recently by several CT manufacturers, and now they are used routinely in coronary CTA. This paper presents our first experience using coronary CTA with 320-CT and the Adaptive Iterative Dose Reduction 3D (AIDR-3D). In addition, we describe the current indications for coronary CTA in our practice as well as the acquisition standard protocols and protocols related to CT application for radiation dose reduction. In conclusion, coronary CTA radiation dose can be dramatically reduced following the 'as low as reasonable achievable' principle by combination of exam indication and well-documented technics for radiation dose reduction, such as beta blockers, low-kV, and also the newest iterative dose reduction software as AIDR-3D. (author)

Angiographic picture of soft tissue desmoid fibromas

International Nuclear Information System (INIS)

Nikitaev, N.S.; Kuznetsova, M.A.

1987-01-01

Arteriography was performed in 35 patients with soft tissue desmoid fibromas. Angiographic semiotics of this disease was described. The frequency of detectability of symptoms in the arterial, parenchymatous and venous phases was analyzed. A tumor in the arterial phase was shown to be of normevascular or moderately hypervascular type without noticeable winding of the nutrient arteries, such features of malignancy as lacunae and ''tumor'' vessels being absent. In the parenchymatous phase desmoid tumors were shown to accumulate moderately a contrast substance, a tumor contour at a vast length was ill defined and poorly marked from surrounding tissues. The venous phase was less noticeable and the time of its appearance was usually within normal. In general by most of its parameters the angiographic picture of agressive fibromatosis corresponded to that of benign tumors and could be used for differential diagnosis of desmoid fibromas and some types of tissue sarcomas

Adult Moyamoya disease angiographic images evolutive characters and treatment methods

International Nuclear Information System (INIS)

Qian Jiangnan; Ling Feng

2000-01-01

Objective: To discuss the angiographic images with evolutional characters and the treatment methods of the Moyamoya disease. Methods: The clinical manifestations, the radiographic changes and the comparative analysis between medicine treatment and surgery treatment, together with the laboratory tests findings were analyzed in one cases adult Moyamoya disease during six years. Conclusions: The angiographic characteristics of MMD show the supplied artery trunk stenosis, and followed by occlusion, with later appearance of vascular smoking sign. Medical treatment proved to be of null. Direct or indirect intra or extra cranial vascular anastomosis are effective for treatment

16-Detector row computed tomographic coronary angiography in patients undergoing evaluation for aortic valve replacement: comparison with catheter angiography

International Nuclear Information System (INIS)

Manghat, N.E.; Morgan-Hughes, G.J.; Broadley, A.J.; Undy, M.B.; Wright, D.; Marshall, A.J.; Roobottom, C.A.

2006-01-01

Aim: To evaluate the diagnostic accuracy of 16-detector row computed tomography (CT) in assessing haemodynamically significant coronary artery stenoses in patients under evaluation for aortic stenosis pre-aortic valve replacement. Subjects and methods: Forty consecutive patients under evaluation for severe aortic stenosis and listed for cardiac catheterization before potential aortic valve replacement underwent coronary artery calcium (CAC) scoring and retrospective electrocardiogram (ECG)-gated multi-detector row computed tomographic coronary angiography (MDCTA) using a GE Lightspeed 16-detector row CT within 1 month of invasive coronary angiography (ICA) for comparative purposes. All 13 major coronary artery segments of the American Heart Association model were evaluated for the presence of ≥50% stenosis and compared to the reference standard. Data were analysed on a segment-by-segment basis and also in 'whole patient' terms. Results: A total of 412/450 segments from 35 patients were suitable for analysis. The overall accuracy of MDCTA for detection of segments with ≥50% stenosis was high, with a sensitivity of 81.3%, specificity 95.0%, positive predictive value (PPV) 57.8%, and negative predictive value (NPV) 98.4%. On a 'whole-patient' basis, 100% (19/19) of patients with significant coronary disease were correctly identified and there were no false-negatives. Excluding patients with CAC >1000 from the analysis improved the accuracy of MDCTA to: sensitivity 90%, specificity 98.1%, PPV 60%, NPV 99.7%. Conclusion: Non-invasive 16-detector row MDCTA accurately excludes significant coronary disease in patients with severe aortic stenosis undergoing evaluation before aortic valve replacement and in whom ICA can therefore be avoided. Its segment-by-segment accuracy is improved further if CAC > 1000 is used as a gatekeeper to MDCTA

The Demise of Skid Row.

Science.gov (United States)

Siegal, Harvey A.; Inciardi, James A.

1982-01-01

Describes the history and evolution of the American skid row; analyzes the changes it has undergone, particularly in the face of urban renewal; and speculates on its future. Includes opinions of the inhabitants of skid row which were obtained from interviews. (MJL)

Contrast bolus technique with rapid CT scanning

International Nuclear Information System (INIS)

Arnold, H.; Kuehne, D.; Rohr, W.; Heller, M.

1981-01-01

Twenty-three patients complying with the clinical criteria for brain death were studied by contrast-enhanced CT. In all but one, the great intracranial vessels escaped visualization; accordingly, angiography demonstrated cerebral circulatory arrest. In the remaining case, faint enhancement of the circle of Willis corresponded to angiographic demonstration of the proximal segments of cerebral arteris. Neither in normal brain nor in dead brain did slow CT scanning disclose any postcontrast increase in parenchymal attenuation. An improved technique is proposed to demonstrate the transit of the contrast bolus by rapid CT with image splitting. If cerebral blood flow is preserved, the grey and white matter will enhance significantly following administration of contrast medium. Vice versa, the absence of enhancement confirms brain death, even in instances in which the great cerebral vessels are obscured by hemorrhage or other extensive lesions. Two additional cases of brain death were evaluated by rapid CT scanning. As to brain death, the technique obviates the need for angiography or radionuclide angiography, usually applied in prospective organ donors, because its informative content is superior to that of either method. The CT technique described affords a reliable and safe diagnosis of brain death, and can be interpreted easily. (orig.)

Standardized CT protocols and nomenclature: better, but not yet there

Energy Technology Data Exchange (ETDEWEB)

Singh, Sarabjeet; Kalra, Mannudeep K. [Harvard Medical School, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States)

2014-10-15

Radiation dose associated with CT is an important safety concern in patient care, especially in children. Technical advancements in multidetector-row CT scanner technology offer several advantages for clinical applications; these advancements have considerably increased CT utilization and enhanced the complexity of CT scanning protocols. Furthermore there are several scan manufacturers spearheading these technical advancements, leading to different commercial names causing confusion among the users, especially at imaging sites with scanners from different vendors. Several scientific studies and the National Council on Radiation Protection and Measurements (NCRP) have shown variation in CT radiation doses for same body region and similar scanning protocols. Therefore there is a need for standardization of scanning protocols and nomenclature of scan parameters. The following material reviews the status and challenges in standardization of CT scanning and nomenclature. (orig.)

Essentials of diagnostic and interventional angiographic technique

International Nuclear Information System (INIS)

Gerlock, A.J.; Mirfakhraee, M.

1985-01-01

This volume presents coverage of basic angiographic techniques and shows how to get to the point of taking the angiogram, and tells how to avoid pitfalls. Particularly valuable is the information on how to get out of trouble if an error is made while manipulating the catheter

A concept of row crater enhancement

International Nuclear Information System (INIS)

Redpath, B.B.

1970-01-01

Linear craters formed by the simultaneous detonation of a row of buried explosives will probably have a wider application than single charges in the explosive excavation of engineering structures. Most cratering experience to date has been with single charges, and an analytical procedure for the design of a row of charges to excavate a crater with a specified configuration has been lacking. There are no digital computer codes having direct application to a row of charges as there are for single charges. This paper derives a simple relationship which can be used to design row charges with some assurance of achieving the desired result and with considerable flexibility in the choice of explosive yield of the individual charges

Development of DIGITEXαPlus digital angiographic system

International Nuclear Information System (INIS)

Imanishi, Tetsuo; Miura, Yusuke; Sasaki, Osamu; Furuyama, Makoto; Yasumi, Masayuki

2001-01-01

The functions required of digital angiographic (DA) systems have been noticeably changing with the recent popularization of the technique of interventional radiology (IVR) in the field of angiography. We have developed a new digital angiographic system, named the DIGITEXαPlus, which is designed to meet the requirements of the latest IVR technologies. The DIGITEXαPlus system is equipped with a high-performance one-million-pixel CCD camera, a newly developed F.P.O. (fluoro-power optimizer), and a contrast-priority radiography control system, which combine together to provide high quality of images both in fluoroscopy and in fluorography. In this new system, a low-dose pulsed fluoroscopy method, employed as standard, minimizes the X-ray doses to patients, and an image controller (IVR MASTER) of a joy stick type provides more diversified functions that its predecessors. These two features enhance the reliability, and simplifies the operation, of the IVR system as a whole. (author)

Analysis of main influence factors on coronary artery image quality with 64-multidetector row helical CT using a pulsating cardiac phantom

International Nuclear Information System (INIS)

Liu Bin; Zhao Hong; Wu Xingwang; Zhang Jiawen; Yu Yongqiang; Liao Jingmin

2006-01-01

Objective: To explore the main influence factors (heart rate, rotation speed, and reconstruction algorithm) on the image quality of coronary artery with 40 mm VCT (64-detector row helical CT) using a pulsating cardiac phantom. Methods: An adjustable pulsating cardiac phantom (GE) containing predetermined simulated coronary arteries was scanned using a 40 mm VCT (GE LightSpeed CT) with cardiac pulsating rates of 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, and 115 beats per minute (bpm). The variable rotation speeds technique of 0.35 s, 0.40 s, and 0.45 s were used, respectively. The raw data were reconstructed using both one-sector and multi-sector reconstruction algorithm at optimal window of the R-R interval. The image quality score (IQS) was evaluated by two radiologists according to the same evaluation standard of reformated image. The correlation between heart rate (HR), roation speed, reconstruction algorithm, and IQS were analyzed. The IQS as independent variable and the HR, rotation speed, reconstruction algorithm as dependent variables were analyzed by multiple linear regression analysis. Results: The heart rate and the reconstruction algorithm had significant influence on IQS. The rotation speed (0.35s, 0.40 s, and 0.45 s) didn't have significant influence on IQS. There was linear regression relationship between heart rate, reconstruction algorithm and IQS (P<0.01). The equation of multiple regression was IQS=5.154-0.046 x (HR) + 0.500 x (reconstruction algorithm). The multi-sector reconstruction algorithm improved the image quality than one-sector did. Conclusion: The main influence factors on the image quality of coronary artery can be evaluated with 40 mm VCT using a pulsating cardiac phantom. It plays an important role in clinical research and application. (authors)

Quantitative thoracic CT techniques in adults: can they be applied in the pediatric population?

Energy Technology Data Exchange (ETDEWEB)

Yoon, Soon Ho [Seoul National University Medical Research Center, Department of Radiology, Seoul National University College of Medicine, and Institute of Radiation Medicine, Seoul (Korea, Republic of); Goo, Jin Mo [Seoul National University Medical Research Center, Department of Radiology, Seoul National University College of Medicine, and Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Cancer Research Institute, Jongno-gu, Seoul (Korea, Republic of); Goo, Hyun Woo [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

2013-03-15

With the rapid evolution of the multidetector row CT technique, quantitative CT has started to be used in clinical studies for revealing a heterogeneous entity of airflow limitation in chronic obstructive pulmonary disease that is caused by a combination of lung parenchymal destruction and remodeling of the small airways in adults. There is growing evidence of a good correlation between quantitative CT findings and pathological findings, pulmonary function test results and other clinical parameters. This article provides an overview of current quantitative thoracic CT techniques used in adults, and how to translate these CT techniques to the pediatric population. (orig.)

Multidetector row computed tomography in bowel obstruction. Part 2. Large bowel obstruction

Energy Technology Data Exchange (ETDEWEB)

Sinha, R. [Department of Radiology, Glenfield Hospital, Leicester (United Kingdom)]. E-mail: rakesh.sinha@uhl-tr.nhs.uk; Verma, R. [Department of Radiology, Glenfield Hospital, Leicester (United Kingdom)

2005-10-01

Large bowel obstruction may present as an emergency as high-grade colonic obstruction and can result in perforation. Perforated large bowel obstruction causes faecal peritonitis, which can result in high morbidity and mortality. Multidetector row computed tomography (MDCT) has the potential of providing an accurate diagnosis of large bowel obstruction. The rapid acquisition of images within one breath-hold reduces misregistration artefacts than can occur in critically ill or uncooperative patients. The following is a review of the various causes of large bowel obstruction with emphasis on important pathogenic factors, CT appearances and the use of multiplanar reformatted images in the diagnostic workup.

Effect of glycoprotein IIb/IIIa receptor inhibition on angiographic complications during percutaneous coronary intervention in the ESPRIT trial.

Science.gov (United States)

Blankenship, J C; Tasissa, G; O'Shea, J C; Iliadis, E A; Bachour, F A; Cohen, D J; Lui, H K; Mann, T; Cohen, E; Tcheng, J E

2001-09-01

We sought to determine whether eptifibatide decreases the incidence of in-laboratory angiographic complications and to determine the relationship of angiographically evident complications to elevations of creatine kinase-MB (CK-MB) enzyme levels during percutaneous coronary intervention. In the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial, eptifibatide during coronary intervention was associated with decreased ischemic complications at 48 h and 30 days. Patients (n = 2,064) were randomized to placebo versus eptifibatide (two 180 microg/kg boluses 10 min apart and as a continuous infusion of 2 microg/kg per min) during percutaneous coronary stenting. Angiographic complications including major dissection, distal embolization, residual thrombus, abrupt closure, residual stenosis >50% and side-branch occlusion were prospectively recorded by the operator. Creatine kinase-MB levels were measured after the procedure and every 6 h thereafter. The incidence of angiographic complications and CK-MB elevation was determined for eptifibatide versus placebo groups. Eptifibatide-treated patients demonstrated nonsignificant trends toward fewer angiographic complications (10 vs. 12% for placebo patients, p = 0.13) and, for patients with angiographic complications, fewer subsequent CK-MB elevations (43 vs. 50% for placebo patients, p = 0.31). In patients without any angiographic complications, the incidence of CK-MB elevation >3 times the normal was 7% with placebo and 4% with eptifibatide (p = 0.003). Eptifibatide during nonurgent coronary stent intervention only minimally (and insignificantly) reduces the incidence of angiographic complications and subsequent CK-MB elevations in patients developing an angiographic complication. The greater effect is to reduce myocardial infarction in patients undergoing otherwise uneventful coronary stent implantation as well as in the overall study population.

Angiographic study of digital arteries in workers exposed to vinyl chloride

Energy Technology Data Exchange (ETDEWEB)

Falappa, P; Magnavita, N; Bergamaschi, A; Colavita, N

1982-05-01

Five patients exposed to vinyl chloride were studied by hand angiography and other non-invasive methods, including photoplethysmography, rheography, and thermography. Raynaud's phenomenon was present in all five subjects, while acro-osteolysis affected only one. Organic vascular lesions, such as narrowing, segmentary occlusions of digital arteries and bridge collaterals, were found in angiographic studies. Only one patient did not show clear segmentary occlusions, but his vessels were crooked and diffusely narrowed. Angiographic results appear to correlate well with the changes shown by non-invasive techniques.

Single-row versus double-row capsulolabral repair: a comparative evaluation of contact pressure and surface area in the capsulolabral complex-glenoid bone interface.

Science.gov (United States)

Kim, Doo-Sup; Yoon, Yeo-Seung; Chung, Hoi-Jeong

2011-07-01

Despite the attention that has been paid to restoration of the capsulolabral complex anatomic insertion onto the glenoid, studies comparing the pressurized contact area and mean interface pressure at the anatomic insertion site between a single-row repair and a double-row labral repair have been uncommon. The purpose of our study was to compare the mean interface pressure and pressurized contact area at the anatomic insertion site of the capsulolabral complex between a single-row repair and a double-row repair technique. Controlled laboratory study. Thirty fresh-frozen cadaveric shoulders (mean age, 61 ± 8 years; range, 48-71 years) were used for this study. Two types of repair were performed on each specimen: (1) a single-row repair and (2) a double-row repair. Using pressure-sensitive films, we examined the interface contact area and contact pressure. The mean interface pressure was greater for the double-row repair technique (0.29 ± 0.04 MPa) when compared with the single-row repair technique (0.21 ± 0.03 MPa) (P = .003). The mean pressurized contact area was also significantly greater for the double-row repair technique (211.8 ± 18.6 mm(2), 78.4% footprint) compared with the single-row repair technique (106.4 ± 16.8 mm(2), 39.4% footprint) (P = .001). The double-row repair has significantly greater mean interface pressure and pressurized contact area at the insertion site of the capsulolabral complex than the single-row repair. The double-row repair may be advantageous compared with the single-row repair in restoring the native footprint area of the capsulolabral complex.

CT of pulmonary emphysema - current status, challenges, and future directions

International Nuclear Information System (INIS)

Litmanovich, Diana; Boiselle, Phillip M.; Bankier, Alexander A.

2009-01-01

Pulmonary emphysema is characterized by irreversible destruction of lung parenchyma. Emphysema is a major contributor to chronic obstructive pulmonary disease (COPD), which by itself is a major cause of morbidity and mortality in the western world. Computed tomography (CT) is an established method for the in-vivo analysis of emphysema. This review first details the pathological basis of emphysema and shows how the subtypes of emphysema can be characterized by CT. The review then shows how CT is used to quantify emphysema, and describes the requirements and foundations for quantification to be accurate. Finally, the review discusses new challenges and their potential solution, notably focused on multi-detector-row CT, and emphasizes the open questions that future research on CT of pulmonary emphysema will have to address. (orig.)

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

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

Diagnostic imaging of acute aortic dissection; Evaluation of thrombosed type aortic dissection by CT and angiography

Energy Technology Data Exchange (ETDEWEB)

Ohya, Tohru; Kumazaki, Tatsuo (Nippon Medical School, Tokyo (Japan))

1991-01-01

One hundred and nineteen patients with aortic dissection who underwent diagnostic imaging were reviewed and angiographic findings as well as those of CT were analysed. Thirty eight cases (43.1%) had non-contrast opacified false lumen, the type of which we call 'thrombosed type aortic dissection'. A comparative study of the thrombosed type with the patent type of false lumens was made particularly from the stand point of the characteristic diagnostic imagings (CT and angiography). At the same time, the pitfalls of these imagings in thrombosed type aortic dissection were studied. At the onset the average age of thrombosed type was 62.3 years old, while that of the patent type was 57.3. A statistical significance between the two groups was p<0.05. Thrombosed type in all cases was caused by atherosclerosis, whereas patent type was caused by the Marfan's syndrome in 11 cases. Other clinical findings, such as initial symptoms and blood pressure revealed no significant differences between the two groups. Pre-contrast CT in acute thrombosed type aortic dissection showed 'hyperdense crescent sign' in 89.4%. However, in 3 cases with thrombosed type in which the pre-contrast CT showed 'hyperdense crescent sign' contrast-enhanced CT detected no clear evidence of aortic dissection in the same site. This was due to obscurity induced by contrast medium. Angiographic findings of thrombosed type were classified into 3 groups: normal type, stenosed true lumen type and ulcer-like projection type. The incidence of normal type was estimated to be 48.4%, whereas stenosed true lumen type was 24.2% and ulcer-like projection was 27.7%. The present study concluded that thrombosed type is not rare in acute aortic dissection and contrast-enhanced CT as well as pre-contrast CT, is of great value in diagnosing thrombosed type. 'Hyperdense crescent sign' in pre-contrast CT is characteristic of intramural hematoma. (author).

Transvenous embolization of cavernous sinus dural arteriovenous fistula via angiographic occlusive inferior petrous sinus

Directory of Open Access Journals (Sweden)

Chao-Bao Luo

2015-09-01

Conclusion: Angiographic occlusive IPS of CSDAVF may be related to true occlusion of IPS or patent IPS with compartment of the IPS-CS. There is no statistically significant difference in procedural times for these two different fistula anatomies. Transvenous embolization via angiographic occlusive IPS is a safe and effective method to manage CSDAVFs.

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

Pitfalls in the use of spiral CT for identification of intracranial aneurysms

International Nuclear Information System (INIS)

Young, N.; Kingston, R.J.; Dorsch, N.W.C.

1999-01-01

We describe problems encountered in our first 136 patients, with 95 aneurysms, who underwent spiral CT for investigation of possible aneurysms involving the circle of Willis and adjacent major vessels, and who had surgical and/or angiographic confirmation. There were seven false-positive cases, of which the first three could be explained by operator inexperience. There were four false negatives, all small aneurysms; two were not seen because of operator error and two were hidden by an adjacent larger aneurysm. Clip artefacts prevented diagnostic studies in six of 21 postoperative studies. One aneurysm was outside the CT field of view, being on a pericallosal artery. One basilar artery tip aneurysm was excluded from the field of the CT study because of a planning error. Inspection of the axial source images is critical if the diagnosis of small or thrombosed aneurysms is to be made. Close attention to image acquisition and computer modelling is required to reduce errors in spiral CT angiography of intracranial aneurysms. (orig.)

Shock Index Correlates with Extravasation on Angiographs of Gastrointestinal Hemorrhage: A Logistics Regression Analysis

International Nuclear Information System (INIS)

Nakasone, Yutaka; Ikeda, Osamu; Yamashita, Yasuyuki; Kudoh, Kouichi; Shigematsu, Yoshinori; Harada, Kazunori

2007-01-01

We applied multivariate analysis to the clinical findings in patients with acute gastrointestinal (GI) hemorrhage and compared the relationship between these findings and angiographic evidence of extravasation. Our study population consisted of 46 patients with acute GI bleeding. They were divided into two groups. In group 1 we retrospectively analyzed 41 angiograms obtained in 29 patients (age range, 25-91 years; average, 71 years). Their clinical findings including the shock index (SI), diastolic blood pressure, hemoglobin, platelet counts, and age, which were quantitatively analyzed. In group 2, consisting of 17 patients (age range, 21-78 years; average, 60 years), we prospectively applied statistical analysis by a logistics regression model to their clinical findings and then assessed 21 angiograms obtained in these patients to determine whether our model was useful for predicting the presence of angiographic evidence of extravasation. On 18 of 41 (43.9%) angiograms in group 1 there was evidence of extravasation; in 3 patients it was demonstrated only by selective angiography. Factors significantly associated with angiographic visualization of extravasation were the SI and patient age. For differentiation between cases with and cases without angiographic evidence of extravasation, the maximum cutoff point was between 0.51 and 0.0.53. Of the 21 angiograms obtained in group 2, 13 (61.9%) showed evidence of extravasation; in 1 patient it was demonstrated only on selective angiograms. We found that in 90% of the cases, the prospective application of our model correctly predicted the angiographically confirmed presence or absence of extravasation. We conclude that in patients with GI hemorrhage, angiographic visualization of extravasation is associated with the pre-embolization SI. Patients with a high SI value should undergo study to facilitate optimal treatment planning

CT urethrography. New imaging technique of the urethra

International Nuclear Information System (INIS)

Takeyama, Nobuyuki; Munechika, Hirotsugu

2005-01-01

The purpose of the study is to assess the usefulness of CT urethrography for evaluation of the posterior urethra and surrounding structures. The CT images were performed with 4 channel multidetector row CT unit. Twenty-six cases (12 cases of CT urethrography and 14 cases of conventional urethrography) were included in this study. 3D-volume rendering (VR) images and VR-multiplaner reconstruction (MPR) sagittal images were compared with conventional retrograde urethrography (RUG) images to evaluate the following anatomical structures; the inferior wall of bladder, the neck of bladder, the posterior urethra, and the prostate. Two radiologists undertook a task of evaluation of the images. There was no significant difference in image quality between RUG and 3D-VR. However, VR-MPR sagittal images were significantly better than RUG or 3D-VR images in any anatomical structures set up beforehand for evaluation. CT urerthrography was useful for evaluation of the posterior urethra and surrounding structures. (author)

64-Slice multidetector row CT angiography of the abdomen: comparison of low versus high concentration iodinated contrast media in a porcine model

Science.gov (United States)

Holalkere, N-S; Matthes, K; Kalva, S P; Brugge, W R; Sahani, D V

2011-01-01

Objective In this study we aimed to assess the image quality and degree of vascular enhancement using low-concentration contrast media (LCCM) (300 mg I ml–1) and high-concentration contrast media (HCCM) (370 mg I ml–1) on 64-slice multidetector row CT (MDCT) abdominal CT angiography (CTA). In addition, we aimed to study the feasibility of using HCCM with a reduced total iodine dose. Methods CTA of the abdomen on a 64-slice MDCT was performed on 15 anaesthetised pigs. Study pigs were divided into three groups of five each based on the iodine concentration and dose received: Group A (LCCM; 300 mg I ml–1), Group B (HCCM; 370 mg I ml–1) and Group C HCCM with 20% less iodine dose. The total iodine injected was kept constant (600 mg kg–1) in Groups A and B. Qualitative and quantitative analyses were performed to study and compare each group for image quality, visibility of the branch order of the superior mesenteric artery (SMA), artefacts, degree of enhancement in the aorta and main stem arteries and uniformity of enhancement in the aorta. Groups were compared using the analysis of variance test. Results The image quality of 64-slice MDCT angiography was excellent with a mean score of 4.63 and confident visualisation of the third to fifth order branches of the SMA in all groups. Group B demonstrated superior vascular enhancement, as compared with Groups A and C (p≤0.05). Uniform aortic enhancement was achieved with the use of LCCM and HCCM with 20% less iodine dose. Conclusion 64-slice MDCT angiography of the abdomen was of excellent quality. HCCM improves contrast enhancement and overall CTA image quality and allows the iodine dose to be reduced. PMID:21081582

Correlation of 64 row MDCT, echocardiography and cardiac catheterization angiography in assessment of pulmonary arterial anatomy in children with cyanotic congenital heart disease

International Nuclear Information System (INIS)

Chandrashekhar, Guruprasadh; Sodhi, Kushaljit Singh; Saxena, Akshay Kumar; Rohit, Manoj Kumar; Khandelwal, Niranjan

2012-01-01

Objective: To study the correlation of low-dose 64-row multi-detector computed tomography (MDCT) with echocardiography and cardiac catheterization angiography (CCA) in the assessment of pulmonary arterial anatomy in children with cyanotic congenital heart disease (CCHD). Materials and methods: This prospective study included 105 children (74 males, 31 females) with CCHD, in the age group of 2 months to 20 years, who underwent 64-row MDCT examination (low-dose CT protocol), echocardiography and CCA for the assessment of pulmonary arteries, including visualization, presence of confluence, stenosis and collaterals. Statistical analysis was performed using the non-parametric statistical analysis test to evaluate the concordance or discordance between echocardiography, MDCT and CCA. Results: 64-row MDCT detected significantly more main and branch pulmonary arteries, patent pulmonary confluences, and more cases of pulmonary artery stenosis. CCA detected more major aorto-pulmonary collaterals than MDCT, whereas echocardiography failed to identify these major aorto-pulmonary collaterals. The effective CT radiation dose to patients less than 2 years of age was in the range of 0.7–2.5 mSv, where as the dose in patients more than 2 years of age ranged from that of 2.1 to 4.2 mSv, which is much less than the radiation dose reported in cardiac catheterization angiography. Conclusion: In cases where cardiac MRI cannot be performed, or is not sufficiently informative, low-dose 64-row MDCT correlates well with CCA and can provide adequate information about pulmonary arterial anatomy in children with cyanotic congenital heart disease, and can replace invasive cardiac catheterization angiography with markedly reduced radiation dosage to the patient.

Optimized control of X-ray exposure and image noise using a particular multislice CT scanner

International Nuclear Information System (INIS)

Yamamoto, Shuji; Suzuki, Masahiro; Kakinuma, Ryutaro; Moriyama, Noriyuki; Koyama, Yoshihiro; Nagasawa, Hirofumi

2008-01-01

Patient dose reduction in computed tomography (CT) always results in a trade off between radiation exposure and image quality. There are few reports that estimate the relationship between image quality and X-ray exposure in CT examinations as one optimal index. The purpose of this study was to determine the optimal parameter settings enabling a low radiation exposure without compromising image quality using a particular 4-row multislice CT (MSCT) scanner (Aquilion VZ 4-slice CT scanner, Toshiba Medical Systems Corporation, Otawara, Tochigi, Japan). Normalized dose divided by image noise for helical pitches (nDNR: normalized dose to noise ratio) were calculated in consideration of beam collimation and tube current-time product. Optimal tube current-time product was calculated using the nDNR for the helical pitches based on user-defined standards of quality of the CT image. As a result, the nDNR proved to be well-supported to decrease the patient exposure in various exposure conditions of MSCT scans; however, the dose and image noise did not show a linear relation to the helical pitch. In conclusion, nDNR can be applied to patient dose reduction while keeping an acceptable image quality using a particular 4-row MSCT scanner. (author)

WE-DE-207A-01: Parallels in the Evolution of X-Ray Angiographic Systems and Devices Used for Minimally Invasive Endovascular Therapy

Energy Technology Data Exchange (ETDEWEB)

Strother, C. [University of Wisconsin (United States)

2016-06-15

1. Parallels in the evolution of x-ray angiographic systems and devices used for minimally invasive endovascular therapy Charles Strother - DSA, invented by Dr. Charles Mistretta at UW-Madison, was the technology which enabled the development of minimally invasive endovascular procedures. As DSA became widely available and the potential benefits for accessing the cerebral vasculature from an endovascular approach began to be apparent, industry began efforts to develop tools for use in these procedures. Along with development of catheters, embolic materials, pushable coils and the GDC coils there was simultaneous development and improvement of 2D DSA image quality and the introduction of 3D DSA. Together, these advances resulted in an enormous expansion in the scope and numbers of minimally invasive endovascular procedures. The introduction of flat detectors for c-arm angiographic systems in 2002 provided the possibility of the angiographic suite becoming not just a location for vascular imaging where physiological assessments might also be performed. Over the last decade algorithmic and hardware advances have been sufficient to now realize this potential in clinical practice. The selection of patients for endovascular treatments is enhanced by this dual capability. Along with these advances has been a steady reduction in the radiation exposure required so that today, vascular and soft tissue images may be obtained with equal or in many cases less radiation exposure than is the case for comparable images obtained with multi-detector CT. Learning Objectives: To understand the full capabilities of today’s angiographic suite To understand how c-arm cone beam CT soft tissue imaging can be used for assessments of devices, blood flow and perfusion. Advances in real-time x-ray neuro-endovascular image guidance Stephen Rudin - Reacting to the demands on real-time image guidance for ever finer neurovascular interventions, great improvements in imaging chains are being

WE-DE-207A-01: Parallels in the Evolution of X-Ray Angiographic Systems and Devices Used for Minimally Invasive Endovascular Therapy

International Nuclear Information System (INIS)

Strother, C.

2016-01-01

1. Parallels in the evolution of x-ray angiographic systems and devices used for minimally invasive endovascular therapy Charles Strother - DSA, invented by Dr. Charles Mistretta at UW-Madison, was the technology which enabled the development of minimally invasive endovascular procedures. As DSA became widely available and the potential benefits for accessing the cerebral vasculature from an endovascular approach began to be apparent, industry began efforts to develop tools for use in these procedures. Along with development of catheters, embolic materials, pushable coils and the GDC coils there was simultaneous development and improvement of 2D DSA image quality and the introduction of 3D DSA. Together, these advances resulted in an enormous expansion in the scope and numbers of minimally invasive endovascular procedures. The introduction of flat detectors for c-arm angiographic systems in 2002 provided the possibility of the angiographic suite becoming not just a location for vascular imaging where physiological assessments might also be performed. Over the last decade algorithmic and hardware advances have been sufficient to now realize this potential in clinical practice. The selection of patients for endovascular treatments is enhanced by this dual capability. Along with these advances has been a steady reduction in the radiation exposure required so that today, vascular and soft tissue images may be obtained with equal or in many cases less radiation exposure than is the case for comparable images obtained with multi-detector CT. Learning Objectives: To understand the full capabilities of today’s angiographic suite To understand how c-arm cone beam CT soft tissue imaging can be used for assessments of devices, blood flow and perfusion. Advances in real-time x-ray neuro-endovascular image guidance Stephen Rudin - Reacting to the demands on real-time image guidance for ever finer neurovascular interventions, great improvements in imaging chains are being

Intra-individual comparison of patient acceptability of multidetector-row CT colonography and double-contrast barium enema

International Nuclear Information System (INIS)

Taylor, S.A.; Halligan, S.; Burling, D.; Bassett, P.; Bartram, C.I.

2005-01-01

AIMS: To compare the subjective acceptability of CT colonography in comparison with barium enema in older symptomatic patients, and to ascertain preferences for future colonic investigation. MATERIALS AND METHODS: The study population comprised 78 persons aged 60 years or over with symptoms suggestive of colorectal neoplasia, who underwent CT colonography followed the same day by barium enema. A 25-point questionnaire was administered after each procedure and an additional follow-up questionnaire a week later. Responses were compared using Wilcoxon matched pairs testing, Mann-Whitney test statistics and binomial exact testing. RESULTS: Participants suffered less physical discomfort during CT colonography (p=0.03) and overall satisfaction was greater compared with barium enema (p=0.03). On follow-up, respondents reported significantly better tolerance of CT colonography (p=0.002), and were less prepared to undergo barium enema again (p<0.001). Of 52 subjects expressing an opinion, all preferred CT to barium enema. CONCLUSION: Patient satisfaction was higher with CT colonography than barium enema. CT colonography caused significantly less physical discomfort and was overwhelmingly preferred by patients

Intra-individual comparison of patient acceptability of multidetector-row CT colonography and double-contrast barium enema

Energy Technology Data Exchange (ETDEWEB)

Taylor, S.A. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom)]. E-mail: csytaylor@yahoo.co.uk; Halligan, S. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Burling, D. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Bassett, P. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Bartram, C.I. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom)

2005-02-01

AIMS: To compare the subjective acceptability of CT colonography in comparison with barium enema in older symptomatic patients, and to ascertain preferences for future colonic investigation. MATERIALS AND METHODS: The study population comprised 78 persons aged 60 years or over with symptoms suggestive of colorectal neoplasia, who underwent CT colonography followed the same day by barium enema. A 25-point questionnaire was administered after each procedure and an additional follow-up questionnaire a week later. Responses were compared using Wilcoxon matched pairs testing, Mann-Whitney test statistics and binomial exact testing. RESULTS: Participants suffered less physical discomfort during CT colonography (p=0.03) and overall satisfaction was greater compared with barium enema (p=0.03). On follow-up, respondents reported significantly better tolerance of CT colonography (p=0.002), and were less prepared to undergo barium enema again (p<0.001). Of 52 subjects expressing an opinion, all preferred CT to barium enema. CONCLUSION: Patient satisfaction was higher with CT colonography than barium enema. CT colonography caused significantly less physical discomfort and was overwhelmingly preferred by patients.

Influence of coronary artery disease prevalence on predictive values of coronary CT angiography: a meta-regression analysis

Energy Technology Data Exchange (ETDEWEB)

Schlattmann, Peter [University Hospital of Friedrich-Schiller University Jena, Department of Medical Statistics, Informatics and Documentation, Jena (Germany); Schuetz, Georg M. [Freie Universitaet Berlin, Charite, Medical School, Department of Radiology, Humboldt-Universitaet zu Berlin, Berlin (Germany); Dewey, Marc [Freie Universitaet Berlin, Charite, Medical School, Department of Radiology, Humboldt-Universitaet zu Berlin, Berlin (Germany); Charite, Institut fuer Radiologie, Berlin (Germany)

2011-09-15

To evaluate the impact of coronary artery disease (CAD) prevalence on the predictive values of coronary CT angiography. We performed a meta-regression based on a generalised linear mixed model using the binomial distribution and a logit link to analyse the influence of the prevalence of CAD in published studies on the per-patient negative and positive predictive values of CT in comparison to conventional coronary angiography as the reference standard. A prevalence range in which the negative predictive value was higher than 90%, while at the same time the positive predictive value was higher than 70% was considered appropriate. The summary negative and positive predictive values of coronary CT angiography were 93.7% (95% confidence interval [CI] 92.8-94.5%) and 87.5% (95% CI, 86.5-88.5%), respectively. With 95% confidence, negative and positive predictive values higher than 90% and 70% were available with CT for a CAD prevalence of 18-63%. CT systems with >16 detector rows met these requirements for the positive (P < 0.01) and negative (P < 0.05) predictive values in a significantly broader range than systems with {<=}16 detector rows. It is reasonable to perform coronary CT angiography as a rule-out test in patients with a low-to-intermediate likelihood of disease. (orig.)

Influence of coronary artery disease prevalence on predictive values of coronary CT angiography: a meta-regression analysis

International Nuclear Information System (INIS)

Schlattmann, Peter; Schuetz, Georg M.; Dewey, Marc

2011-01-01

To evaluate the impact of coronary artery disease (CAD) prevalence on the predictive values of coronary CT angiography. We performed a meta-regression based on a generalised linear mixed model using the binomial distribution and a logit link to analyse the influence of the prevalence of CAD in published studies on the per-patient negative and positive predictive values of CT in comparison to conventional coronary angiography as the reference standard. A prevalence range in which the negative predictive value was higher than 90%, while at the same time the positive predictive value was higher than 70% was considered appropriate. The summary negative and positive predictive values of coronary CT angiography were 93.7% (95% confidence interval [CI] 92.8-94.5%) and 87.5% (95% CI, 86.5-88.5%), respectively. With 95% confidence, negative and positive predictive values higher than 90% and 70% were available with CT for a CAD prevalence of 18-63%. CT systems with >16 detector rows met these requirements for the positive (P < 0.01) and negative (P < 0.05) predictive values in a significantly broader range than systems with ≤16 detector rows. It is reasonable to perform coronary CT angiography as a rule-out test in patients with a low-to-intermediate likelihood of disease. (orig.)

Angiographic CT with intravenous contrast agent application for monitoring of intracranial flow diverting stents

International Nuclear Information System (INIS)

Saake, Marc; Struffert, Tobias; Goelitz, Philipp; Ott, Sabine; Doerfler, Arnd; Seifert, Frank; Ganslandt, Oliver

2012-01-01

Intracranial flow diverting devices are increasingly used to treat cerebral aneurysms. A reliable, non-invasive follow-up modality would be desirable. Our aim was to compare intra-arterial digital subtraction angiography (ia DSA) to angiographic computed tomography with intravenous contrast agent application (iv ACT) in the visualisation of flow diverting devices and aneurysm lumina. Follow-up monitoring by iv ACT (n = 36) and ia DSA (n = 25) in 14 patients treated with flow diverting devices for intracranial aneurysms was evaluated retrospectively. Images were evaluated by two neuroradiologists in anonymous consensus reading regarding the device deployment, wall apposition, neck coverage of the aneurysm, opacification of the vessel and device lumen, as well as the degree of aneurysm occlusion. Corresponding ia DSA and iv ACT images were scored identically in all patients regarding the stent deployment, wall apposition and neck coverage, as well as the degree of aneurysm occlusion and patency status of the device and parent artery. Opacification of the parent vessel lumen and perfused parts of the aneurysm was considered slightly inferior for iv ACT in comparison with ia DSA (seven of 36 cases), without impact on diagnosis. We demonstrated the feasibility and diagnostic value of iv ACT in follow-up imaging of intracranial flow diverting devices. Due to its high spatial resolution and non-invasive character, this novel technique might become a valuable imaging modality in these patients. (orig.)

Comparison of the image quality between volumetric and conventional high-resolution CT with 64-slice row CT

International Nuclear Information System (INIS)

Gao Yanli; Zhang Lei; Zhao Xia; Ma Min; Zhai Renyou

2008-01-01

Objective: To compare the image quality between volumetric high-resolution CT (VHRCT) and conventional high-resolution CT (CHRCT), and investigate the feasibility of VHRCT. Methods: Catphan 412 phantom was scanned with protocols of CHRCT and VHRCT on a set of GE Lightspeed VCT. The spatial-resolution (LP/cm), noise (standard deviation in an ROI) and radiation close (CTDI) were recorded for each CT scan. Difference of noise between CHRCT and VHRCT were evaluated by paired t test. In clinical study, 32 patients were scanned with VHRCT and CHRCT protocols. The image quality of CHRCT and VHRCT was rated and compared. The quality difference between CHRCT and VHRCT was assessed by Wilcoxon paired signed rank sum test. Results: In phantom study, the in-plane spatial-resolution of both VHRCT and CHRCT was 11 LP/cm for axial images and 12 LP/cm for coronal reformatted images. The noise of VHRCT and CHRCT was (69.18±2.77)HU and (54.62±2.12) HU respectively (t=-15.929, P 0.05). The quality assessment scores of VHRCT coronal reformatted images and CHRCT coronal reformatted images were 3.05 and 1.88 respectively with significant difference (Z= -5.088, P<0.01). Conclusion: The image quality of VHRCT cross-sectional image is similar to that of CHRCT. Multiplanar images with high resolution of VHRCT are recommended. The radiation dose of VHRCT remains to be optimized. (authors)

A novel method for the angiographic estimation of the percentage of spleen volume embolized during partial splenic embolization

Energy Technology Data Exchange (ETDEWEB)

Ou, Ming-Ching; Chuang, Ming-Tsung [Department of Diagnostic Radiology, National Cheng-Kung University Hospital, No. 138 Sheng Li Road, Tainan 704, Taiwan, ROC (China); Lin, Xi-Zhang [Department of Internal Medicine, National Cheng-Kung University Hospital, No. 138 Sheng Li Road, Tainan 704, Taiwan, ROC (China); Tsai, Hong-Ming; Chen, Shu-Yuan [Department of Diagnostic Radiology, National Cheng-Kung University Hospital, No. 138 Sheng Li Road, Tainan 704, Taiwan, ROC (China); Liu, Yi-Sheng, E-mail: taicheng100704@yahoo.com.tw [Department of Diagnostic Radiology, National Cheng-Kung University Hospital, No. 138 Sheng Li Road, Tainan 704, Taiwan, ROC (China)

2013-08-15

Purpose: To evaluate the efficacy of estimating the volume of spleen embolized in partial splenic embolization (PSE) by measuring the diameters of the splenic artery and its branches. Materials and methods: A total of 43 liver cirrhosis patients (mean age, 62.19 ± 9.65 years) with thrombocytopenia were included. Among these, 24 patients underwent a follow-up CT scan which showed a correlation between angiographic estimation and measured embolized splenic volume. Estimated splenic embolization volume was calculated by a method based on diameters of the splenic artery and its branches. The diameters of each of the splenic arteries and branches were measured via 2D angiographic images. Embolization was performed with gelatin sponges. Patients underwent follow-up with serial measurement of blood counts and liver function tests. The actual volume of embolized spleen was determined by computed tomography (CT) measuring the volumes of embolized and non-embolized spleen two months after PSE. Results: PSE was performed without immediate major complications. The mean WBC count significantly increased from 3.81 ± 1.69 × 10{sup 3}/mm{sup 3} before PSE to 8.56 ± 3.14 × 10{sup 3}/mm{sup 3} at 1 week after PSE (P < 0.001). Mean platelet count significantly increased from 62.00 ± 22.62 × 10{sup 3}/mm{sup 3} before PSE to 95.40 ± 46.29 × 10{sup 3}/mm{sup 3} 1 week after PSE (P < 0.001). The measured embolization ratio was positively correlated with estimated embolization ratio (Spearman's rho [ρ] = 0.687, P < 0.001). The mean difference between the actual embolization ratio and the estimated embolization ratio was 16.16 ± 8.96%. Conclusions: The method provides a simple method to quantitatively estimate embolized splenic volume with a correlation of measured embolization ratio to estimated embolization ratio of Spearman's ρ = 0.687.

Training Rowing with Virtual Environments

Directory of Open Access Journals (Sweden)

Gopher Daniel

2011-12-01

Full Text Available This paper presents the results of the design, implementation and evaluation of a platform for rowing training in Virtual Reality called SPRINT. The paper discusses how various aspects of the rowing skill can be analyzed and trained over a single common methodology and system platform. The result is a vision for new directions in the domain of sport training with Virtual Reality.

Memory hierarchy using row-based compression

Science.gov (United States)

Loh, Gabriel H.; O'Connor, James M.

2016-10-25

A system includes a first memory and a device coupleable to the first memory. The device includes a second memory to cache data from the first memory. The second memory includes a plurality of rows, each row including a corresponding set of compressed data blocks of non-uniform sizes and a corresponding set of tag blocks. Each tag block represents a corresponding compressed data block of the row. The device further includes decompression logic to decompress data blocks accessed from the second memory. The device further includes compression logic to compress data blocks to be stored in the second memory.

Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

International Nuclear Information System (INIS)

Hanson, Eric H.; Roach, Cayce J.; Ringdahl, Erik N.; Wynn, Brad L.; DeChancie, Sean M.; Mann, Nathan D.; Diamond, Alan S.; Orrison, William W.

2011-01-01

Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

Energy Technology Data Exchange (ETDEWEB)

Hanson, Eric H. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); Amigenics, Inc, Las Vegas, NV (United States); Roach, Cayce J. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); University of Nevada Las Vegas, School of Life Sciences, Las Vegas, NV (United States); Ringdahl, Erik N. [University of Nevada Las Vegas, Department of Psychology, Las Vegas, NV (United States); Wynn, Brad L. [Family Medicine Spokane, Spokane, WA (United States); DeChancie, Sean M.; Mann, Nathan D. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); Diamond, Alan S. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); Orrison, William W. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); University of Nevada School of Medicine, Department of Medical Education, Reno, NV (United States)

2011-05-15

Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

On Row Rank Equal Column Rank

Science.gov (United States)

Khalili, Parviz

2009-01-01

We will prove a well-known theorem in Linear Algebra, that is, for any "m x n" matrix the dimension of row space and column space are the same. The proof is based on the subject of "elementary matrices" and "reduced row-echelon" form of a matrix.

Dose reduction in multidetector CT of the urinary tract. Studies in a phantom model

International Nuclear Information System (INIS)

Coppenrath, E.; Meindl, T.; Herzog, P.; Khalil, R.; Mueller-Lisse, U.; Krenn, L.; Reiser, M.; Mueller-Lisse, U.G.

2006-01-01

A novel ureter phantom was developed for investigations of image quality and dose in CT urography. The ureter phantom consisted of a water box (14 cm x 32 cm x 42 cm) with five parallel plastic tubes (diameter 2.7 mm) filled with different concentrations of contrast media (1.88-30 mg iodine/ml). CT density of the tubes and noise of the surrounding water were determined using two multidetector scanners (Philips MX8000 with four rows, Siemens Sensation 16 with 16 rows) with varying tube current-time product (15-100 mAs per slice), voltage (90 kV, 100 kV, 120 kV), pitch (0.875-1.75), and slice thickness (1 mm, 2 mm, 3.2 mm). Contrast-to-noise ratio as a parameter of image quality was correlated with dose (CTDI) and was compared with image evaluation by two radiologists. The CT densities of different concentrations of contrast media and contrast-to-noise ratio were significantly higher when low voltages (90 kV versus 120 kV, 100 kV versus 120 kV) were applied. Smaller slice thickness (1 mm versus 2 mm) did not change CT density but decreased contrast-to-noise ratio due to increased noise. Contrast phantom studies showed favourable effects of low tube voltage on image quality in the low dose range. This may facilitate substantial dose reduction in CT urography. (orig.)

Evaluation of occurring complications after flow diverter treatment of elastase-induced aneurysm in rabbits using micro-CT and MRI at 9.4 T

Energy Technology Data Exchange (ETDEWEB)

Simgen, Andreas; Ley, Desiree; Muehl-Benninghaus, Ruben; Koerner, Heiko; Reith, Wolfgang; Yilmaz, Umut [Saarland University Hospital, Department of Neuroradiology, Homburg, Saar (Germany); Roth, Christian [Clinic Bremen-Mitte, Department of Neuroradiology, Bremen (Germany); Cattaneo, Giorgio Franco Maria [Acandis GmbH, Pforzheim (Germany); Mueller, Andreas [Saarland University Hospital, Department of Experimental Surgery, Homburg, Saar (Germany); Kim, Yoo-Jin [Saarland University Hospital, Department of Pathology, Homburg, Saar (Germany); Scheller, Bruno [Saarland University Hospital, Department of Cardiology, Homburg, Saar (Germany)

2016-10-15

Flow diverters are increasingly being used to treat intracranial aneurysms. This study evaluates occurring complications of flow-diverting devices in the treatment of experimental aneurysms, involving the use of micro-CT and small animal MRI at 9.4 T, in correlation to angiographic and histological findings. We previously published two preclinical studies, in which we assessed two different flow diverters in the treatment of elastase-induced aneurysms. Devices have been implanted across the aneurysm neck as well as in the abdominal aorta. From these studies, a total of 65 devices (prototype FD (n = 30) and Derivo embolization device (n = 35)) additionally underwent micro-CT and MRI after angiographic follow-up and before being histologically examined. The different architectures of both devices were precisely comparable due to high-resolution micro-CT imaging. Micro-CT revealed wire fractures in nine cases (30 %) only with the prototype FD. In three cases (10 %), severe wire fractures correlated with an in-stent stenosis due to intimal hyperplasia. Other complications, like distal stent occlusions and post-stent stenosis, were seen in both groups and verified with both imaging techniques. Osseous metaplasia were correlated to calcifications seen with micro-CT. MRI enabled visualization of the position of the implanted devices relative to the aneurysm and revealed incomplete aneurysm neck coverage with the prototype FD in two cases (6.7 %). Micro-CT and 9.4-T MRI are valid to discover and understand occurring complications of flow diverters in the preclinical phase and can serve as evaluation tools to minimize complication rates of endovascular devices in the future. (orig.)

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.

Multidetector row CT angiography of living related renal donors: Is there a need for venous phase imaging?

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Namasivayam, Saravanan [Department of Radiology, Division of Abdominal Imaging, Emory University School of Medicine, 1364 Clifton Road NE, Atlanta, GA 30322 (United States); Kalra, Mannudeep K. [Department of Radiology, Division of Abdominal Imaging, Emory University School of Medicine, 1364 Clifton Road NE, Atlanta, GA 30322 (United States); Waldrop, Sandra M. [Department of Radiology, Division of Abdominal Imaging, Emory University School of Medicine, 1364 Clifton Road NE, Atlanta, GA 30322 (United States); Mittal, Pardeep K. [Department of Radiology, Division of Abdominal Imaging, Emory University School of Medicine, 1364 Clifton Road NE, Atlanta, GA 30322 (United States); Small, William C. [Department of Radiology, Division of Abdominal Imaging, Emory University School of Medicine, 1364 Clifton Road NE, Atlanta, GA 30322 (United States)]. E-mail: wsmall@emory.edu

2006-09-15

Objective: To prospectively evaluate whether renal venous anatomy can be detected from arterial phase images of multidetector row CT (MDCT) of renal donors. Material and methods: Institutional review board approved our study protocol with waiver of consent. Forty-eight consecutive renal donors (age range, 21-56 years; M:F, 20:28) referred for MDCT evaluation were included. Two sub-specialty radiologists performed an independent and separate evaluation of renal venous anatomy in arterial and venous phase images. Opacification of renal venous structures was scored on a five-point scale (1-not seen; 3-minimal opacification; 5-excellent opacification). Arterial and venous phase opacification scores were compared by Wilcoxon signed rank test. Results: Both readers detected all renal venous anomalies in arterial as well as venous phase images. Each reader detected accessory right renal veins (n = 14), retroaortic left renal vein (n = 2), circumaortic left renal vein (n = 1), and left renal hilar arteriovenous malformation (n = 1) in arterial phase images. Retroaortic left renal venous branch was difficult to differentiate from lumbar vein (reader-1, n = 1; reader-2, n = 2) in both arterial and venous phase images. Sensitivity of detection of renal veins, left adrenal, gonadal and lumbar veins in arterial phase images was 100, 83-88, 100, and 85-90%, respectively. As expected, venous phase images showed significantly greater opacification of renal veins, left gonadal, adrenal and lumbar veins (p < .05). However, this did not substantially limit the evaluation of renal venous anatomy in arterial phase images. Both readers had substantial interobserver agreement (kappa coefficient, 0.7; p < 0.05). Conclusions: Arterial phase MDCT images alone can be used to detect renal venous anomalies, and to identify small left renal venous branches namely, the left gonadal, adrenal and lumbar veins in renal donors. Venous phase MDCT acquisition is not necessary for evaluation of renal

Multidetector row CT angiography of living related renal donors: Is there a need for venous phase imaging?

International Nuclear Information System (INIS)

Namasivayam, Saravanan; Kalra, Mannudeep K.; Waldrop, Sandra M.; Mittal, Pardeep K.; Small, William C.

2006-01-01

Objective: To prospectively evaluate whether renal venous anatomy can be detected from arterial phase images of multidetector row CT (MDCT) of renal donors. Material and methods: Institutional review board approved our study protocol with waiver of consent. Forty-eight consecutive renal donors (age range, 21-56 years; M:F, 20:28) referred for MDCT evaluation were included. Two sub-specialty radiologists performed an independent and separate evaluation of renal venous anatomy in arterial and venous phase images. Opacification of renal venous structures was scored on a five-point scale (1-not seen; 3-minimal opacification; 5-excellent opacification). Arterial and venous phase opacification scores were compared by Wilcoxon signed rank test. Results: Both readers detected all renal venous anomalies in arterial as well as venous phase images. Each reader detected accessory right renal veins (n = 14), retroaortic left renal vein (n = 2), circumaortic left renal vein (n = 1), and left renal hilar arteriovenous malformation (n = 1) in arterial phase images. Retroaortic left renal venous branch was difficult to differentiate from lumbar vein (reader-1, n = 1; reader-2, n = 2) in both arterial and venous phase images. Sensitivity of detection of renal veins, left adrenal, gonadal and lumbar veins in arterial phase images was 100, 83-88, 100, and 85-90%, respectively. As expected, venous phase images showed significantly greater opacification of renal veins, left gonadal, adrenal and lumbar veins (p < .05). However, this did not substantially limit the evaluation of renal venous anatomy in arterial phase images. Both readers had substantial interobserver agreement (kappa coefficient, 0.7; p < 0.05). Conclusions: Arterial phase MDCT images alone can be used to detect renal venous anomalies, and to identify small left renal venous branches namely, the left gonadal, adrenal and lumbar veins in renal donors. Venous phase MDCT acquisition is not necessary for evaluation of renal

Cerebellar hemangioblastomas with computed tomographic, angiographic, and positron-emission tomographic evaluations

International Nuclear Information System (INIS)

Kikuchi, Kenji; Sakamoto, Tetsuya; Kowada, Masayoshi; Tamakawa, Yoshiharu; Uemura, Kazuo.

1986-01-01

Ten patients with cerebellar hemangioblastomas were reviewed, and evaluations were made by computed tomography (CT), vertebral angiography, and positron-emission tomography (PET). Cerebellar hemangioblastomas were classified into three types on the basis of their CT appearances: Type I: a cystic tumor without a demonstrable mural nodule; Type II: a cystic tumor with a mural nodule, and Type III: a solid tumor without any cyst formation. All of the cystic tumors classified here as Types I and II were associated with a shift and deformity of the fourth ventricule and an enlarged lateral ventricle, and yet no low-density area in the adjacent cerebellar tissue indicating perifocal edema was demonstrated. By contrast, in the solid hemangioblastomas designated as Type III, finger-shaped, low-density areas were visualized around the enhancing mass lesion, extending to the white matter of the entire affected cerebellar hemisphere. The vertebral angiographic classification of cerebellar hemangioblastomas was also attempted as follows: Type I: an avascular tumor without a demonstrable mural nodule; Type II: an avascular tumor with a mural nodule, and Type III: a solid vascular tumor with enlarged feeding arteries and distinct draining veins. In Type II, a relatively small mural nodule was visualized, fed mostly by a single feeding artery, and the tumor stain was at its peak at the arterial phase. No draining vein was opacified in most cases. In contrast, solid tumors classified as Type III were demonstrated to be hypervascular tumors with a multiplicity of feeding arteries and draining veins. The vascular mass remained to be opacified through the venous phase with delayed blood circulation. PET was performed on a 31-year-old male with a solid hemangioblastoma. (J.P.N)

Value of Virtual Colonoscopy with 64 Row CT in Evaluation of Colorectal Cancer

International Nuclear Information System (INIS)

Zaleska-Dorobisz, Urszula; Łasecki, Mateusz; Nienartowicz, Ewa; Pelak, Joanna; Słonina, Joanna; Olchowy, Cyprian; Ścieżka, Marek; Sąsiadek, Marek

2014-01-01

Virtual colonoscopy (VC) enables three-dimensional view of walls and internal lumen of the colon as a result of reconstruction of multislice CT images. The role of VC in diagnosis of the colon abnormalities systematically increases, and in many medical centers all over the world is carried out as a screening test of patients with high risk of colorectal cancer. We analyzed results of virtual colonoscopy of 360 patients with clinical suspicion of colorectal cancer. Sensitivity and specificity of CT colonoscopy for detection of colon cancers and polyps were assessed. Results of our research have shown high diagnostic efficiency of CT colonoscopy in detection of focal lesions in large intestine of 10 mm or more diameter. Sensitivity was 85.7%, specificity 89.2%. Virtual colonoscopy is noninvasive and well tolerated by patients imaging method, which permits for early detection of the large intestine lesions with specificity and sensitivity similar to classical colonoscopy in screening exams in patients suspected for colorectal cancer. Good preparation of the patients for the examination is very important for proper diagnosis and interpretation of this imaginge procedure

Serum high sensitivity C-reactive protein levels and the severity of coronary atherosclerosis assessed by angiographic gensini score

International Nuclear Information System (INIS)

Masood, A.; Jafar, S.S.; Akram, Z.

2011-01-01

Objective: To assess the relationship between plasma high sensitivity C-reactive protein levels with severity of coronary atherosclerosis. Materials and Methods: The study included 80 patients subjected to coronary angiography. The extent of Coronary Artery Disease (CAD) was assessed using Gensini score. Patients were divided into three risk groups according to hs-CRP levels ( 3mg/L- as high risk). Mean Angiographic Gensini scores were compared among the risk groups. Correlation between serum hs-CRP levels and angiographic Gensini scores was also assessed. Results: The 26 (32.5%) patients belonging to hs-CRP low-risk group had a mean angiographic Gensini score of 11.8 +- 5.8, 18 (22.5%) belonging to moderate-risk group had a mean score of 28.9 +- 7.9 and 36 (45%) belonging to high- risk group had a mean score of 78.7 +- 41.0. By applying ANOVA the mean angiographic Gensini scores showed increasing trend from lower to higher hs-CRP risk groups (p < 0.001). Serum hs-CRP levels showed significant correlation with respective angiographic Gensini scores by Pearson's correlation (p < 0.001). Conclusion: Serum hs-CRP levels show significant correlation with the severity of Coronary Artery Disease as assessed by angiographic Gensini score. (author)

Hepatic angiographic findings of ruptured hepatocellular carcinoma: 'Sentinel signs' versus extravasation

International Nuclear Information System (INIS)

Yun, Seong Jong; Nam, Deok Ho

2014-01-01

This study retrospectively compared the accuracy of angiographic sentinel signs (sentinel vessels, hypovascular areas, and delayed dots) with extravasation in the diagnosis of ruptured hepatocellular carcinoma (HCC). Sixteen patients diagnosed with HCC between March 2007 and November 2011 were evaluated. Among the patients, we identified 32 HCCs (19 ruptured, 13 unruptured), and assessed all HCCs by hepatic angiography with regard to extravasation, sentinel vessels, hypovascular areas, and delayed dots. We compared the sensitivity and specificity of the sentinel signs with those of the extravasation for the diagnosis of a ruptured HCC. For the angiographic diagnosis of a ruptured HCC, the sensitivity of the sentinel signs (sentinel vessel, 63.2%; hypovascular area, 89.5%; delayed dot, 72.7%) was higher than the sensitivity of extravasation (15.8%). The difference in sensitivity between each sentinel sign and extravasation was statistically significant (sentinel vessel, p = 0.012; hypovascular area, p < 0.001; delayed dot, p 0.039). The specificity of sentinel signs for the diagnosis of ruptured HCC was not statistically different from the specificity of extravasation. Sentinel signs are more accurate than extravasation for the angiographic diagnosis of a ruptured HCC.

Transarterial embolization in the management of intractable epistaxis: the angiographic findings and results based on etiologies.

Science.gov (United States)

Wang, Bin; Zu, Qing-Quan; Liu, Xing-Long; Zhou, Chun-Gao; Xia, Jin-Guo; Zhao, Lin-Bo; Shi, Hai-Bin; Liu, Sheng

2016-08-01

Transarterial embolization (TAE) appears to be a safe and effective treatment for patients with intractable epistaxis, despite different etiologies or angiography findings. Idiopathic epistaxis is prone to present with negative angiographic findings. To retrospectively evaluate the safety and effectiveness of TAE for intractable epistaxis, and focus on the factors of etiology and angiographic findings. From March 2008 to December 2014, the data of 43 patients with intractable bleeding undergoing TAE were reviewed. The outcomes of interventional therapy were assessed according to different etiology (malignant or benign disease) and angiographic finding (positive or negative angiogram). Positive angiographic findings were found in 11 of 12 cases with malignant diseases and 22 of 31 cases with benign diseases, respectively (p = 0.237). Among the 10 cases with negative angiographic findings, the negative angiography rate of idiopathic epistaxis was higher than that of epistaxis with definite etiology (p = 0.003). Bleeding was controlled successfully in all of the 43 patients after embolization. During the mean follow-up period of 24.0 ± 16.7 months, five patients relapsed. No significant difference was found in recurrence rates between malignant and benign diseases or between positive and negative angiography (p = 0.241, p = 0.704, respectively).

Cerebral angiographic changes on serial examination of a patient with migraine

Energy Technology Data Exchange (ETDEWEB)

Masuzawa, T.; Shinoda, S.; Nakahara, N.; Abe, F.; Sato, F.; Furuse, M.

1983-03-01

Curious cerebral angiographic changes are described in a 27-year-old female migraine patient. During the period of observation of this patient, both the intracranial carotid artery and the vertebrobasilar artery systems presented unusual and fascinating cerebral arteriographic pictures. In an attack of migraine, angiography showed that all the intracranial secondary and tertiary branches of the carotid arterial system were dilated without showing any changes in the extracranial arteries and when the migraine attack had subsided, all branches of the carotid arteries as well as the vertebrobasilar arteries demonstreated abnormal segmental narrowings or vasospasm. These sequential angiographic changes have not been hitherto reported in migraine.

CT urography

Energy Technology Data Exchange (ETDEWEB)

Korobkin, M. [Dept. of Radiology, Univ. of Michigan, Ann Arbor, MI (United States)

2005-11-15

With the advent of multidetector row CT scanners, evaluation of the urothelium of the entire urinary tract with high-resolution thin sections during a single breath-hold has become a reality. Multidetector CT urography (MDCTU) is a single examination that allows evaluation of potential urinary tract calculi, renal parenchymal masses, and both benign and malignant urothelial lesions. Initial results with this new technique are encouraging. Current investigations of MDCTU focus on methods to improve opacification and distension of the upper urinary tract - the collecting systems, pelvis, and ureters. The role of abdominal compression, infusion of saline and/or furosemide, and optimal time delay of excretory phase imaging is being explored. Upper tract urothelial malignancies, including small lesions less the 5 mmin diameter, can be detected with high sensitivity. Methods to reduce radiation exposure are being explored, including split-bolus contrast injection techniques that combine nephrographic and excretory phases into a single phase. It is likely that in the near future, radiological evaluation of significant unexplained hematuria or of known or prior urothelial malignancy will consist of a single examination - MDCTU. (orig.)

Benefit of cone-beam computed tomography angiography in acute management of angiographically undetectable ruptured arteriovenous malformations.

Science.gov (United States)

Rahal, Jason P; Malek, Adel M

2013-10-01

Ruptured arteriovenous malformations (AVMs) are a frequent cause of intracerebral hemorrhage (ICH). In some cases, compression from the associated hematoma in the acute setting can partially or completely occlude an AVM, making it invisible on conventional angiography techniques. The authors report on the successful use of cone-beam CT angiography (CBCT-A) to precisely identify the underlying angioarchitecture of ruptured AVMs that are not visible on conventional angiography. Three patients presented with ICH for which they underwent examination with CBCT-A in addition to digital subtraction angiography and other imaging modalities, including MR angiography and CT angiography. All patients underwent surgical evacuation due to mass effect from the hematoma. Clinical history, imaging studies, and surgical records were reviewed. Hematoma volumes were calculated. In all 3 cases, CBCT-A demonstrated detailed anatomy of an AVM where no lesion or just a suggestion of a draining vein had been seen with other imaging modalities. Magnetic resonance imaging demonstrated enhancement in 1 patient; CT angiography demonstrated a draining vein in 1 patient; 2D digital subtraction angiography and 3D rotational angiography demonstrated a suggestion of a draining vein in 2 cases and no finding in the third. In the 2 patients in whom CBCT-A was performed prior to surgery, the demonstrated AVM was successfully resected without evidence of a residual lesion. In the third patient, CBCT-A allowed precise targeting of the AVM nidus using Gamma Knife radiosurgery. Cone-beam CT angiography should be considered in the evaluation and subsequent treatment of ICH due to ruptured AVMs. In cases in which the associated hematoma compresses the AVM nidus, CBCT-A can have higher sensitivity and anatomical accuracy than traditional angiographic modalities, including digital subtraction angiography.

CT coronary angiographic evaluation of suspected anginal chest pain.

Science.gov (United States)

Moss, Alastair J; Newby, David E

2016-02-15

Non-invasive imaging plays a critical role in the assessment of patients presenting with suspected angina chest pain. However, wide variations in practice across Europe and North America highlight the lack of consensus in selecting the appropriate first-line test for the investigation of coronary artery disease (CAD). CT coronary angiography (CTCA) has a high negative predictive value for excluding the presence of CAD. As such, it serves as a potential 'gatekeeper' to downstream testing by reducing the rate of inappropriate invasive coronary angiography. Two recent large multicentre randomised control trials have provided insights into whether CTCA can be incorporated into chest pain care pathways to improve risk stratification of CAD. They demonstrate that using CTCA enhances diagnostic certainty and improves the targeting of appropriate invasive investigations and therapeutic interventions. Importantly, reductions in cardiac death and non-fatal myocardial infarction appear to be attained through the more appropriate use of preventative therapy and coronary revascularisation when guided by CTCA. With this increasing portfolio of evidence, CTCA should be considered the non-invasive investigation of choice in the evaluation of patients with suspected angina pectoris due to coronary heart disease. NCT01149590, post-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Biomechanical characteristics of single-row repair in comparison to double-row repair with consideration of the suture configuration and suture material.

Science.gov (United States)

Baums, M H; Buchhorn, G H; Spahn, G; Poppendieck, B; Schultz, W; Klinger, H-M

2008-11-01

The aim of the study was to evaluate the time zero mechanical properties of single- versus double-row configuration for rotator cuff repair in an animal model with consideration of the stitch technique and suture material. Thirty-two fresh-frozen sheep shoulders were randomly assigned to four repair groups: suture anchor single-row repair coupled with (1) braided, nonabsorbable polyester suture sized USP No. 2 (SRAE) or (2) braided polyblend polyethylene suture sized No. 2 (SRAH). The double-row repair was coupled with (3) USP No. 2 (DRAE) or (4) braided polyblend polyethylene suture No. 2 (DRAH). Arthroscopic Mason-Allen stitches were used (single-row) and combined with medial horizontal mattress stitches (double-row). Shoulders were cyclically loaded from 10 to 180 N. Displacement to gap formation of 5- and 10-mm at the repair site, cycles to failure, and the mode of failure were determined. The ultimate tensile strength was verified in specimens that resisted to 3,000 cycles. DRAE and DRAH had a lower frequency of 5- (P = 0.135) and 10-mm gap formation (P = 0.135). All DRAE and DRAH resisted 3,000 cycles while only three SRAE and one SRAH resisted 3,000 cycles (P row specimens was significantly higher than in others (P 0.05). Double-row suture anchor repair with arthroscopic Mason-Allen/medial mattress stitches provides initial strength superior to single-row repair with arthroscopic Mason-Allen stitches under isometric cyclic loading as well as under ultimate loading conditions. Our results support the concept of double-row fixation with arthroscopic Mason-Allen/medial mattress stitches in rotator cuff tears with improvement of initial fixation strength and ultimate tensile load. Use of new polyblend polyethylene suture material seems not to increase the initial biomechanical aspects of the repair construct.

Biomechanical comparison of double-row versus transtendon single-row suture anchor technique for repair of the grade III partial articular-sided rotator cuff tears.

Science.gov (United States)

Zhang, Chun-Gang; Zhao, De-Wei; Wang, Wei-Ming; Ren, Ming-Fa; Li, Rui-Xin; Yang, Sheng; Liu, Yu-Peng

2010-11-01

For partial-thickness tears of the rotator cuff, double-row fixation and transtendon single-row fixation restore insertion site anatomy, with excellent results. We compared the biomechanical properties of double-row and transtendon single-row suture anchor techniques for repair of grade III partial articular-sided rotator cuff tears. In 10 matched pairs of fresh-frozen sheep shoulders, the infraspinatus tendon from 1 shoulder was repaired with a double-row suture anchor technique. This comprised placement of 2 medial anchors with horizontal mattress sutures at an angle of ≤ 45° into the medial margin of the infraspinatus footprint, just lateral to the articular surface, and 2 lateral anchors with horizontal mattress sutures. Standardized, 50% partial, articular-sided infraspinatus lesions were created in the contralateral shoulder. The infraspinatus tendon from the contralateral shoulder was repaired using two anchors with transtendon single-row mattress sutures. Each specimen underwent cyclic loading from 10 to 100 N for 50 cycles, followed by tensile testing to failure. Gap formation and strain over the footprint area were measured using a motion capture system; stiffness and failure load were determined from testing data. Gap formation for the transtendon single-row repair was significantly smaller (P row repair for the first cycle ((1.74 ± 0.38) mm vs. (2.86 ± 0.46) mm, respectively) and the last cycle ((3.77 ± 0.45) mm vs. (5.89 ± 0.61) mm, respectively). The strain over the footprint area for the transtendon single-row repair was significantly smaller (P row repair. Also, it had a higher mean ultimate tensile load and stiffness. For grade III partial articular-sided rotator cuff tears, transtendon single-row fixation exhibited superior biomechanical properties when compared with double-row fixation.

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

Single versus double-row repair of the rotator cuff: does double-row repair with improved anatomical and biomechanical characteristics lead to better clinical outcome?

Science.gov (United States)

Pauly, Stephan; Gerhardt, Christian; Chen, Jianhai; Scheibel, Markus

2010-12-01

Several techniques for arthroscopic repair of rotator cuff defects have been introduced over the past years. Besides established techniques such as single-row repairs, new techniques such as double-row reconstructions have gained increasing interest. The present article therefore provides an overview of the currently available literature on both repair techniques with respect to several anatomical, biomechanical, clinical and structural endpoints. Systematic literature review of biomechanical, clinical and radiographic studies investigating or comparing single- and double-row techniques. These results were evaluated and compared to provide an overview on benefits and drawbacks of the respective repair type. Reconstructions of the tendon-to-bone unit for full-thickness tears in either single- or double-row technique differ with respect to several endpoints. Double-row repair techniques provide more anatomical reconstructions of the footprint and superior initial biomechanical characteristics when compared to single-row repair. With regard to clinical results, no significant differences were found while radiological data suggest a better structural tendon integrity following double-row fixation. Presently published clinical studies cannot emphasize a clearly superior technique at this time. Available biomechanical studies are in favour of double-row repair. Radiographic studies suggest a beneficial effect of double-row reconstruction on structural integrity of the reattached tendon or reduced recurrent defect rates, respectively.

An unusual case of left aberrant innominate artery with right aortic arch: evaluation with high-resolution CT

Energy Technology Data Exchange (ETDEWEB)

Calcagni, Giulio [University Rene Descartes-Paris 5, Department of Pediatric Cardiology, Hopital Necker Enfants Malades, Paris (France); Gesualdo, Francesco; Brunelle, Francis; Ou, Phalla [University Rene Descartes-Paris 5, Department of Pediatric Radiology, Hopital Necker Enfants Malades, Paris Cedex 15 (France)

2008-01-15

A left aberrant innominate (brachiocephalic) artery is an angiographically well-known entity that may cause tracheal compression. We report a male newborn who was admitted for further investigation of a prenatally suspected major vessel anomaly. High-resolution CT was used to completely assess the abnormal anatomy and the relationship with the airway, as well as to guide the surgical approach for its correction. (orig.)

An unusual case of left aberrant innominate artery with right aortic arch: evaluation with high-resolution CT

International Nuclear Information System (INIS)

Calcagni, Giulio; Gesualdo, Francesco; Brunelle, Francis; Ou, Phalla

2008-01-01

A left aberrant innominate (brachiocephalic) artery is an angiographically well-known entity that may cause tracheal compression. We report a male newborn who was admitted for further investigation of a prenatally suspected major vessel anomaly. High-resolution CT was used to completely assess the abnormal anatomy and the relationship with the airway, as well as to guide the surgical approach for its correction. (orig.)

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.

Development of Functional Electrical Stimulation Rowing: The Rowstim Series.

Science.gov (United States)

Andrews, Brian; Gibbons, Robin; Wheeler, Garry

2017-11-01

Potentially, functional electrical stimulation (FES)-assisted exercise may have an important therapeutic role in reducing comorbidities associated with spinal cord injury (SCI). Here, we present an overview of these secondary life-threatening conditions, discuss the rationale behind the development of a hybrid exercise called FES rowing, and describe our experience in developing FES rowing technology. FES rowing and sculling are unique forms of adaptive rowing for those with SCI. The paralyzed leg musculature is activated by multiple channels of electrical pulses delivered via self-adhesive electrodes attached to the skin. The stimulated muscle contractions are synchronized with voluntary rowing movements of the upper limbs. A range of steady-state FES rowing exercise intensities have been demonstrated from 15.2 ± 1.8 mL/kg/min in tetraplegia to 22.9 ±7.1 mL/kg/min in paraplegia. We expect that such high levels may help some to achieve significant reductions in the risks to their health, particularly where a dose-response relationship exists as is the case for cardiovascular disease and Type II diabetes. Furthermore, preliminary results suggest that cyclical forces more than 1.5 times body weight are imposed on the leg long bones which may help to reduce the risk of fragility fractures. We have demonstrated the feasibility of FES rowing on land and water using adapted rowing technology that includes; a fixed stretcher indoor ergometer (adapted Concept 2, Model E), a floating stretcher indoor ergometer (adapted Concept 2 Dynamic), a turbine powered water rowing tank, a custom hydraulic sculling simulator and a single scull (adapted Alden 16). This has involved volunteers with paraplegia and tetraplegia with SCI ranging from C4 to T12 AIS A using at least 4-channels of surface electrical stimulation. FES rowers, with SCI, have competed alongside non-SCI rowers over the Olympic distance of 2000 m at the British Indoor Rowing Championships in 2004, 2005, and 2006

Clinical and angiographic predictors of haemodynamically significant angiographic lesions: development and validation of a risk score to predict positive fractional flow reserve.

Science.gov (United States)

Sareen, Nishtha; Baber, Usman; Kezbor, Safwan; Sayseng, Sonny; Aquino, Melissa; Mehran, Roxana; Sweeny, Joseph; Barman, Nitin; Kini, Annapoorna; Sharma, Samin K

2017-04-07

Coronary revascularisation based upon physiological evaluation of lesions improves clinical outcomes. Angiographic or visual stenosis assessment alone is insufficient in predicting haemodynamic stenosis severity by fractional flow reserve (FFR) and therefore cannot be used to guide revascularisation, particularly in the lesion subset system formulated. Of 1,023 consecutive lesions (883 patients), 314 (31%) were haemodynamically significant. Characteristics associated with FFR ≤0.8 include male gender, higher SYNTAX score, lesions ≥20 mm, stenosis >50%, bifurcation, calcification, absence of tortuosity and smaller reference diameter. A user-friendly integer score was developed with the five variables demonstrating the strongest association. On prospective validation (in 279 distinct lesions), the increasing value of the score correlated well with increasing haemodynamic significance (C-statistic 0.85). We identified several clinical and angiographic characteristics and formulated a scoring system to guide the approach to intermediate lesions. This may translate into cost savings. Larger studies with prospective validation are required to confirm our results.

Rectal cancer staging: Multidetector-row computed tomography diagnostic accuracy in assessment of mesorectal fascia invasion

Science.gov (United States)

Ippolito, Davide; Drago, Silvia Girolama; Franzesi, Cammillo Talei; Fior, Davide; Sironi, Sandro

2016-01-01

AIM: To assess the diagnostic accuracy of multidetector-row computed tomography (MDCT) as compared with conventional magnetic resonance imaging (MRI), in identifying mesorectal fascia (MRF) invasion in rectal cancer patients. METHODS: Ninety-one patients with biopsy proven rectal adenocarcinoma referred for thoracic and abdominal CT staging were enrolled in this study. The contrast-enhanced MDCT scans were performed on a 256 row scanner (ICT, Philips) with the following acquisition parameters: tube voltage 120 KV, tube current 150-300 mAs. Imaging data were reviewed as axial and as multiplanar reconstructions (MPRs) images along the rectal tumor axis. MRI study, performed on 1.5 T with dedicated phased array multicoil, included multiplanar T2 and axial T1 sequences and diffusion weighted images (DWI). Axial and MPR CT images independently were compared to MRI and MRF involvement was determined. Diagnostic accuracy of both modalities was compared and statistically analyzed. RESULTS: According to MRI, the MRF was involved in 51 patients and not involved in 40 patients. DWI allowed to recognize the tumor as a focal mass with high signal intensity on high b-value images, compared with the signal of the normal adjacent rectal wall or with the lower tissue signal intensity background. The number of patients correctly staged by the native axial CT images was 71 out of 91 (41 with involved MRF; 30 with not involved MRF), while by using the MPR 80 patients were correctly staged (45 with involved MRF; 35 with not involved MRF). Local tumor staging suggested by MDCT agreed with those of MRI, obtaining for CT axial images sensitivity and specificity of 80.4% and 75%, positive predictive value (PPV) 80.4%, negative predictive value (NPV) 75% and accuracy 78%; while performing MPR the sensitivity and specificity increased to 88% and 87.5%, PPV was 90%, NPV 85.36% and accuracy 88%. MPR images showed higher diagnostic accuracy, in terms of MRF involvement, than native axial images

Yellapragada SubbaRow

Indian Academy of Sciences (India)

Admin

filariasis, needs to use tetracycline antibiotics against plague and bacterial ... mouth existence. Deeply affected by poverty at home, SubbaRow .... which forced him to stay on deck during the journey. He was the ..... pregnant women of.

Coronary arterial Disease associated with arteriosclerosis in lower extremity: Angiographic analysis

International Nuclear Information System (INIS)

Kim, Ji Hye; Chung, Jin Wook; Lee, Seon Kyu; Han, Joon Koo; Park, Jae Hyung; Kim, Jae Seung; Han, Man Chung

1993-01-01

We performed both peripheral and coronary angiographies in 52 patients with an arteriosclerosis in lower extremities. The severity of arteriosclerotic narrowing of the coronary and peripheral arteries were compared on angiographies. An angiographic vascular score(AVS, 0-5) reflecting the number and the degree of stenosis in 12 lower extremity arteries and three major coronary arteries was assigned to each angiogram and the sun of scores in the lower extremity arteries was compared with the incidence of significant coronary artery disease (more than grade 3) and coronary score. Relation of incidence and severity of vascular stenosis and risk factors (diabetes metallitus, hypertension, smoking, and hypercholesterolemia) was also analyzed. Thirty-four of 52 patients (65%) had an angiographically significant coronary artery disease. Thirteen of these 34 patients (38%) had no clinical symptom and sign of the ischemic heart disease. There was no statistically significant difference in the incidence and severity of coronary artery disease between high (more than 30) and low AVS group in lower extremity (p>0.14). All patients had at least one risk factor and 49 of 52 patients (94%) had multiple risk factors. Coronary angiography was normal in there patients with only one risk factors, and angiographically significant coronary artery disease existed in nine of 16 cases (56.3%) with two risk factors. 13 of 17 case (76.5%) with three risk factors, and 12 of 16 cases (75.0%) with all four risk factors. There were no significant correlations between individual risk factors and incidence, severity of arteriosclerosis in coronary and lower extremity arteries. In conclusion, angiographic evaluation of the coronary artery disease in patients with lower extremity arteriosclerosis is necessary because of the high chance of coronary artery disease and difficulty in the prediction of coronary artery disease with a severity of the peripheral arteriosclerosis, presence of various risk

Staff dosimetry and risk assessment during digestive and angiographic examinations

International Nuclear Information System (INIS)

Pages, J.; Osteaux, M.

2001-01-01

The use of ionizing radiation in medical applications involves not only a risk for the patient, but also for the staff which executed the related examinations. The dose to the forehead, neck, fingers and wrist of a radiologist and an assisting nurse were measured with thermoluminescent dosimeters during angiographic and digestive examinations respectively. Dose to eye lenses and effective dose were estimated for a working period of one year. Effective doses were under the established limit of 20 mSv per year. Nurse eye lens dose was higher than the limit of 150 mSv. Differences of a factor of 3.8 were observed between nurse and radiologist doses. Angiographic procedures are considered as high risk examinations, however, digestive examinations can have a higher risk than interventional procedures. (author)

Respiratory-gated segment reconstruction for radiation treatment planning using 256-slice CT-scanner during free breathing

Science.gov (United States)

Mori, Shinichiro; Endo, Masahiro; Kohno, Ryosuke; Minohara, Shinichi; Kohno, Kazutoshi; Asakura, Hiroshi; Fujiwara, Hideaki; Murase, Kenya

2005-04-01

The conventional respiratory-gated CT scan technique includes anatomic motion induced artifacts due to the low temporal resolution. They are a significant source of error in radiotherapy treatment planning for the thorax and upper abdomen. Temporal resolution and image quality are important factors to minimize planning target volume margin due to the respiratory motion. To achieve high temporal resolution and high signal-to-noise ratio, we developed a respiratory gated segment reconstruction algorithm and adapted it to Feldkamp-Davis-Kress algorithm (FDK) with a 256-detector row CT. The 256-detector row CT could scan approximately 100 mm in the cranio-caudal direction with 0.5 mm slice thickness in one rotation. Data acquisition for the RS-FDK relies on the assistance of the respiratory sensing system by a cine scan mode (table remains stationary). We evaluated RS-FDK in phantom study with the 256-detector row CT and compared it with full scan (FS-FDK) and HS-FDK results with regard to volume accuracy and image noise, and finally adapted the RS-FDK to an animal study. The RS-FDK gave a more accurate volume than the others and it had the same signal-to-noise ratio as the FS-FDK. In the animal study, the RS-FDK visualized the clearest edges of the liver and pulmonary vessels of all the algorithms. In conclusion, the RS-FDK algorithm has a capability of high temporal resolution and high signal-to-noise ratio. Therefore it will be useful when combined with new radiotherapy techniques including image guided radiation therapy (IGRT) and 4D radiation therapy.

Biomechanical determinants of elite rowing technique and performance.

Science.gov (United States)

Buckeridge, E M; Bull, A M J; McGregor, A H

2015-04-01

In rowing, the parameters of injury, performance, and technique are all interrelated and in dynamic equilibrium. Whilst rowing requires extreme physical strength and endurance, a high level of skill and technique is essential to enable an effective transfer of power through the rowing sequence. This study aimed to determine discrete aspects of rowing technique, which strongly influence foot force production and asymmetries at the foot-stretchers, as these are biomechanical parameters often associated with performance and injury risk. Twenty elite female rowers performed an incremental rowing test on an instrumented rowing ergometer, which measured force at the handle and foot-stretchers, while three-dimensional kinematic recordings of the ankle, knee, hip, and lumbar-pelvic joints were made. Multiple regression analyses identified hip kinematics as a key predictor of foot force output (R(2)  = 0.48), whereas knee and lumbar-pelvic kinematics were the main determinants in optimizing the horizontal foot force component (R(2)  = .41). Bilateral asymmetries of the foot-stretchers were also seen to significantly influence lumbar-pelvic kinematics (R(2)  = 0.43) and pelvic twisting (R(2)  = 0.32) during the rowing stroke. These results provide biomechanical evidence toward aspects of technique that can be modified to optimize force output and performance, which can be of direct benefit to coaches and athletes. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Myocardial enhancement pattern in patients with acute myocardial infarction on two-phase contrast-enhanced Ecg-gated multidetector-row computed tomography

International Nuclear Information System (INIS)

Ko, S.M.; Seo, J.B.; Hong, M.K.; Do, K.H.; Lee, S.H.; Lee, J.S.; Song, J.W.; Park, S.J.; Park, S.W.; Lim, T.H.

2006-01-01

Aim: To evaluate the myocardial enhancement pattern of the left ventricle on two-phase contrast-enhanced electrocardiogram (ECG)-gated multidetector computed tomography (MDCT) images in patients with acute myocardial infarction (AMI). METHODS: Two-phase contrast-enhanced ECG-gated MDCT examinations were performed in 16 patients with AMI. The presence, location and pattern of myocardial enhancement were evaluated. MDCT findings were compared with the catheter angiographic results. RESULTS: Subendocardial (n=9) or transmural (n=6) area of early perfusion defects of the myocardium was detected in 15 of 16 patients (94%) on early-phase CT images. Variable delayed myocardial enhancement patterns on late-phase CT images were observed in 12 patients (75%): (1) subendocardial residual perfusion defect and subepicardial late enhancement (n=6); (2) transmural late enhancement (n=1); (3) isolated subendocardial late enhancement (n=1); and (4) isolated subendocardial residual perfusion defect (n=2). On catheter angiography, 14 of 15 corresponding coronary arteries showed significant stenosis. CONCLUSION: Variable abnormal myocardial enhancement pattern was seen on two-phase, contrast-enhanced ECG-gated MDCT in patients with AMI. Assessment of myocardial attenuation on CT angiography gives additional information of the location and extent of infarction

Biomechanical comparison of double-row locking plates versus single- and double-row non-locking plates in a comminuted metacarpal fracture model.

Science.gov (United States)

Gajendran, Varun K; Szabo, Robert M; Myo, George K; Curtiss, Shane B

2009-12-01

Open or unstable metacarpal fractures frequently require open reduction and internal fixation. Locking plate technology has improved fixation of unstable fractures in certain settings. In this study, we hypothesized that there would be a difference in strength of fixation using double-row locking plates compared with single- and double-row non-locking plates in comminuted metacarpal fractures. We tested our hypothesis in a gap metacarpal fracture model simulating comminution using fourth-generation, biomechanical testing-grade composite sawbones. The metacarpals were divided into 6 groups of 15 bones each. Groups 1 and 4 were plated with a standard 6-hole, 2.3-mm plate in AO fashion. Groups 2 and 5 were plated with a 6-hole double-row 3-dimensional non-locking plate with bicortical screws aimed for convergence. Groups 3 and 6 were plated with a 6-hole double-row 3-dimensional locking plate with unicortical screws. The plated metacarpals were then tested to failure against cantilever apex dorsal bending (groups 1-3) and torsion (groups 4-6). The loads to failure in groups 1 to 3 were 198 +/- 18, 223 +/- 29, and 203 +/- 19 N, respectively. The torques to failure in groups 4 to 6 were 2,033 +/- 155, 3,190 +/- 235, and 3,161 +/- 268 N mm, respectively. Group 2 had the highest load to failure, whereas groups 5 and 6 shared the highest torques to failure (p row plates had equivalent bending and torsional stiffness, significantly higher than observed for the single-row non-locking plate. No other statistical differences were noted between groups. When subjected to the physiologically relevant forces of apex dorsal bending and torsion in a comminuted metacarpal fracture model, double-row 3-dimensional non-locking plates provided superior stability in bending and equivalent stability in torsion compared with double-row 3-dimensional locking plates, whereas single-row non-locking plates provided the least stability.

The pharmaco-kinetics of angiographic contrast media with special reference to the extravascular spaces. Fundamental studies on dogs for the characterization of angiographic media. Pt. 1

International Nuclear Information System (INIS)

Lagemann, K.

1975-01-01

The pharmaco-kinetics of angiographic contrast media in the extra-vascular space, which are largely unknown, were investigated experimentally in dogs. As part of a basic study, using radio-active contrast media, it was possible to determine the concentration and rate of elimination in practically all organs and tissues. Measurements were carried out first after prolonged infusion of contrast under conditions of balanced flow, and secondly six hours after the end of the infusion. It was therefore possible to determine the inflow and loss of contrast medium in various organs, or organs systems. The most commonly used angiographic contrast media in Germany were investigated. Their kinetic behaviour is largely identical, their pattern of distribution and elimination depended principally on the organ or tissue. (orig.) [de

Biomechanical Performance of Medial Row Suture Placement Relative to the Musculotendinous Junction in Transosseous Equivalent Suture Bridge Double-Row Rotator Cuff Repair.

Science.gov (United States)

Virk, Mandeep S; Bruce, Benjamin; Hussey, Kristen E; Thomas, Jacqueline M; Luthringer, Tyler A; Shewman, Elizabeth F; Wang, Vincent M; Verma, Nikhil N; Romeo, Anthony A; Cole, Brian J

2017-02-01

To compare the biomechanical performance of medial row suture placement relative to the musculotendinous junction (MTJ) in a cadaveric transosseous equivalent suture bridge (TOE-SB) double-row (DR) rotator cuff repair (RCR) model. A TOE-SB DR technique was used to reattach experimentally created supraspinatus tendon tears in 9 pairs of human cadaveric shoulders. The medial row sutures were passed either near the MTJ (MTJ group) or 10 mm lateral to the MTJ (rotator cuff tendon [RCT] group). After the supraspinatus repair, the specimens underwent cyclic loading and load to failure tests. The localized displacement of the markers affixed to the tendon surface was measured with an optical tracking system. The MTJ group showed a significantly higher (P = .03) medial row failure (5/9; 3 during cyclic testing and 2 during load to failure testing) compared with the RCT group (0/9). The mean number of cycles completed during cyclic testing was lower in the MTJ group (77) compared with the RCT group (100; P = .07) because 3 specimens failed in the MTJ group during cyclic loading. There were no significant differences between the 2 study groups with respect to biomechanical properties during the load to failure testing. In a cadaveric TOE-SB DR RCR model, medial row sutures through the MTJ results in a significantly higher rate of medial row failure. In rotator cuff tears with tendon tissue loss, passage of medial row sutures through the MTJ should be avoided in a TOE-SB RCR technique because of the risk of medial row failure. Copyright © 2016. Published by Elsevier Inc.

Evaluation of pituitary adenomas by multidirectional multislice dynamic CT

International Nuclear Information System (INIS)

Abe, T.; Izumiyama, H.; Fujisawa, I.

2002-01-01

Purpose: Multidetector-row CT is a new technology with a short scanning time. Multislice dynamic CT (MSDCT) in various directions can be obtained using the multidetector-row CT with multiplanar reformatting (MPR) technique. Material and Methods: We evaluated the initial results of sagittal and coronal MSDCT images reconstructed by MPR (MSDCT-MPR) in 3 pituitary adenoma patients with a pacemaker. Results: In a patient with microadenoma, the maximum contrast between the normal anterior pituitary gland and the adenoma occurred approximately 50 s after the start of the contrast medium injection. A microadenoma was depicted as a less enhanced area relative to normal pituitary tissue. The macroadenomas were depicted as a less enhanced mass with cavernous sinus invasion in 1 patient and as a non-uniformly enhanced mass in another patient. Bone destruction and incomplete opening of the sellar floor during previous surgery were clearly detected in 2 patients with macroadenomas. These pituitary adenomas were removed via the transnasal route based on information from the MSDCT-MPR images only. The findings were verified surgically. Conclusion: The MSDCT-MPR provided the information needed for surgery with good image quality in the 3 patients with pacemakers. MSDCT-MPR appears to be a useful technique for patients with a pituitary adenoma in whom MR imaging is not available. This is the first report, to our knowledge, of the MSDCT-MPR technique being used to demonstrate pituitary disorders

Evaluation of pituitary adenomas by multidirectional multislice dynamic CT

Energy Technology Data Exchange (ETDEWEB)

Abe, T.; Izumiyama, H. [Showa Univ. School of Medicine, Tokyo (Japan). Dept. of Neurosurgery; Fujisawa, I. [Kishiwada City Hospital, Kishiwada (Japan). Dept. of Radiology

2002-11-01

Purpose: Multidetector-row CT is a new technology with a short scanning time. Multislice dynamic CT (MSDCT) in various directions can be obtained using the multidetector-row CT with multiplanar reformatting (MPR) technique. Material and Methods: We evaluated the initial results of sagittal and coronal MSDCT images reconstructed by MPR (MSDCT-MPR) in 3 pituitary adenoma patients with a pacemaker. Results: In a patient with microadenoma, the maximum contrast between the normal anterior pituitary gland and the adenoma occurred approximately 50 s after the start of the contrast medium injection. A microadenoma was depicted as a less enhanced area relative to normal pituitary tissue. The macroadenomas were depicted as a less enhanced mass with cavernous sinus invasion in 1 patient and as a non-uniformly enhanced mass in another patient. Bone destruction and incomplete opening of the sellar floor during previous surgery were clearly detected in 2 patients with macroadenomas. These pituitary adenomas were removed via the transnasal route based on information from the MSDCT-MPR images only. The findings were verified surgically. Conclusion: The MSDCT-MPR provided the information needed for surgery with good image quality in the 3 patients with pacemakers. MSDCT-MPR appears to be a useful technique for patients with a pituitary adenoma in whom MR imaging is not available. This is the first report, to our knowledge, of the MSDCT-MPR technique being used to demonstrate pituitary disorders.

Double-Row Capsulolabral Repair Increases Load to Failure and Decreases Excessive Motion.

Science.gov (United States)

McDonald, Lucas S; Thompson, Matthew; Altchek, David W; McGarry, Michelle H; Lee, Thay Q; Rocchi, Vanna J; Dines, Joshua S

2016-11-01

Using a cadaver shoulder instability model and load-testing device, we compared biomechanical characteristics of double-row and single-row capsulolabral repairs. We hypothesized a greater reduction in glenohumeral motion and translation and a higher load to failure in a mattress double-row capsulolabral repair than in a single-row repair. In 6 matched pairs of cadaveric shoulders, a capsulolabral injury was created. One shoulder was repaired with a single-row technique, and the other with a double-row mattress technique. Rotational range of motion, anterior-inferior translation, and humeral head kinematics were measured. Load-to-failure testing measured stiffness, yield load, deformation at yield load, energy absorbed at yield load, load to failure, deformation at ultimate load, and energy absorbed at ultimate load. Double-row repair significantly decreased external rotation and total range of motion compared with single-row repair. Both repairs decreased anterior-inferior translation compared with the capsulolabral-injured condition, however, no differences existed between repair types. Yield load in the single-row group was 171.3 ± 110.1 N, and in the double-row group it was 216.1 ± 83.1 N (P = .02). Ultimate load to failure in the single-row group was 224.5 ± 121.0 N, and in the double-row group it was 373.9 ± 172.0 N (P = .05). Energy absorbed at ultimate load in the single-row group was 1,745.4 ± 1,462.9 N-mm, and in the double-row group it was 4,649.8 ± 1,930.8 N-mm (P = .02). In cases of capsulolabral disruption, double-row repair techniques may result in decreased shoulder rotational range of motion and improved load-to-failure characteristics. In cases of capsulolabral disruption, repair techniques with double-row mattress repair may provide more secure fixation. Double-row capsulolabral repair decreases shoulder motion and increases load to failure, yield load, and energy absorbed at yield load more than single-row repair. Published by

Significance of pelvic CT examination for the diagnosis of the distal colonic and rectal cancer

International Nuclear Information System (INIS)

Shindo, Takeshi

1984-01-01

Pelvic CT examination was performed in preoperative 40 patients and postoperrative 51 patients of the distal colonic and rectal carcinoma. CT study expect for the decision of the depth of invasion and the detection of lymphnode metastasis, or the location of recurrence. Diagnostic accuracy rate of the depth of invasion was 68.6% in tumors of sigmoid colon, rectosigmoid, and upper rectum, and 78.9% in lower rectum, and anal canal. These rate were superior to those of selective angiographic examination. Diagnostic accuracy rate for lymphnode metastasis was 73.0%. CT examination could define the lymphnode swelling, but could not define if those were metastasis or not. Furthermore, CT-angiography was beneficial for the estimation of the depth of invasion. The differentiation between local recurrent tumor and granulomatous mass in the perineum after abdomino-perineal resection is the most important problem, however, the further studies are necessary to obtain the definite criteria of differential diagnosis. Above results support that CT examination should be used routinely in the distal colonic and rectal cancer patients. (author)

Spontaneous coronary artery dissection: complete angiographic resolution without stenting

Directory of Open Access Journals (Sweden)

Alexandre Abizaid

2007-09-01

Full Text Available A case of spontaneous coronary artery dissection in a 49-year-oldwoman is presented. She did not present the classical cardiovascular riskfactors. Etiology and treatment are discussed. She underwent primarypercutaneous coronary intervention of the left anterior descendingartery with no stenting and had complete angiographic resolution.

Comparison of 16-row multislice CT angiography with conventional angiography for detection and evaluation of intracranial aneurysms

International Nuclear Information System (INIS)

Donmez, Halil; Serifov, Elman; Kahriman, Guven; Mavili, Ertugrul; Durak, Ahmet Candan; Menkue, Ahmet

2011-01-01

Purpose: The aim of this study is to compare the diagnostic performance of 16-row computed tomographic angiography (MDCTA) with digital subtraction angiography (DSA) for the detection and characterization of intracranial aneurysms in patients with nontraumatic subarachnoid hemorrhages (SAH). Materials and methods: One-hundred and twelve consecutive patients with suspected intracranial aneurysm underwent both 16-row MDCTA and DSA. The MDCT angiograms were interpreted in a blinded fashion by using combination with VRI, MIP and MPR techniques. Sensitivity specificity and accuracy were calculated for the CTA and DSA. The results were compared with each other. The DSA reader's interpretation was accepted as the reference standard. Results: A total of 164 aneurysms were detected at DSA in 112 patients, no aneurysms were detected by DSA and MDCTA in 16 patients. Eight aneurysms were missed by MDCTA. The overall sensitivity, specificity, and accuracy of MDCTA on a per-aneurysm basis were 95.1%, 94.1%, and 95%, respectively. According to the size of the aneurysm less than 3 mm; sensitivity, specificity and diagnostic accuracy of MDCTA were 86.1%, 94.1%, 88.6%, respectively. Conclusion: This study suggests that MDCTA is equally as sensitive as DSA in the detection of intracranial aneurysms of greater than 3 mm, and it also reveals 100% detection rate for ruptured aneurysms.

Angiographic Guidewire with Measuring Markers: Design and Clinical Experience

International Nuclear Information System (INIS)

Kamei, Seiji; Ishiguchi, Tsuneo; Murata, Katsuhito; Matsuda, Joe; Ohno, Ryota; Kimura, Junko; Nakamura, Atsushi; Ohno, Kazuko; Kawamura, Toshiki; Ikeda, Mitsuru

2006-01-01

Purpose. We have developed an angiographic guidewire with measuring markers to determine accurately how far a guidewire is inserted within a catheter. We investigated whether use of this guidewire reduces the risk of vascular injury and the fluoroscopic time during guidewire manipulations. Methods. Four markers were put on the surface of the guidewire at 80, 100, 110, and 120 cm from the tip. The actual lengths of 54 catheters from seven manufacturers were measured and compared with the nominal lengths. Sixty consecutive patients who underwent angiography were randomized into two groups: in one group guidewires with surface markers were used (marker group) and in the other group, conventional guidewires (control group). For each guidewire insertion, the fluoroscopic time before the guidewire was pushed forward into the vessel lumen was recorded. The number of occasions on which unintentionally the guidewire had already been pushed out of the catheter at the start of fluoroscopy was also evaluated. Results. The actual lengths of all catheters were greater than the nominal lengths by 1.0-11.0 cm. Mean fluoroscopic time for each guidewire insertion was 3.3 sec in the marker group and 5.7 sec in the control group (p < 0.05). Guidewires were unintentionally pushed out of the catheters without fluoroscopy three times (3.6%), in each case in the control group. Conclusion. The guidewire with measuring markers is effective for enhancing safety and in reducing fluoroscopic radiation during angiographic procedures. It is recommended that operators be aware that actual lengths of catheters may vary significantly from the nominal lengths listed; they should be aware of this with any guidewire, but particularly with the angiographic measuring guidewire

Rasch models with exchangeable rows and columns

DEFF Research Database (Denmark)

Lauritzen, Steffen Lilholt

The article studies distributions of doubly infinite binary matrices with exchangeable rows and columns which satify the further property that the probability of any $m \\times n$ submatrix is a function of the row- and column sums of that matrix. We show that any such distribution is a (unique...

Emergencies in the retroperitoneum: assessment of spread of disease by helical CT

Energy Technology Data Exchange (ETDEWEB)

Scialpi, M. E-mail: michelescialpi@libero.it; Scaglione, M.; Angelelli, G.; Lupattelli, L.; Resta, M.C.; Resta, M.; Rotondo, A

2004-04-01

Acute pancreatitis, leaking abdominal aortic aneurysm, and renal trauma frequently occur in the setting of patients with abdominal nontraumatic and traumatic injury; it represents the most urgent conditions that may determine the presence of fluid collections or haematoma in the retroperitoneum. Single spiral CT and multidetector-row CT (MDCT) play an important role in diagnosis of retroperitoneal emergencies, providing useful informations on the type, site, extent and management of the fluid collections. An accurate CT assessment requires the awareness of the existence of dissectable retroperitoneal fascial planes. Fluid collections or haematoma tends to escape the retroperitoneal site of origin into planes extend from the diaphragm to the pelvic floor. We assess the multicompartimental anatomy of the retroperitoneum and the pathway of spread of the most frequent retroperitoneal fluid collections or haematoma by helical CT.

Don't Rock the Boat : How Antiphase Crew Coordination Affects Rowing

NARCIS (Netherlands)

de Brouwer, Anouk J.; de Poel, Harjo J.; Hofmijster, Mathijs J.

2013-01-01

It is generally accepted that crew rowing requires perfect synchronization between the movements of the rowers. However, a long-standing and somewhat counterintuitive idea is that out-of-phase crew rowing might have benefits over in-phase (i.e., synchronous) rowing. In synchronous rowing, 5 to 6% of

Angiographic diagnosis of hemorrhage tumours of the small intestine

International Nuclear Information System (INIS)

Vadon, G.; Ehngloner, L.; Petri, K.

1980-01-01

2 angiographic investigations in small intestine tumors, accompanied with hemorrhage are considered. Conclusion is made that the most suitable moment for estimation of small intestine hemorrhage, according to the proper and literature data, is selective angiography. Wide application of the technique for preoperative detection of gastro-inestinal hemorrhage is recommended

Characteristics of forming of synonymic rows within lexical phraseological field

Directory of Open Access Journals (Sweden)

Мария Валерьевна Волнакова

2011-03-01

Full Text Available The article deals with the characteristics of forming of phraseological synonymic rows with a lexical identifier as a dominant of a row. Revealed synonymic rows mirror the deepness of systematic language relationships between lexis and phraseology.

Puerperal thrombo-phlebitis of the ovarian veins: Diagnosis by means of CT

International Nuclear Information System (INIS)

Huber, D.J.

1984-01-01

Two cases of puerperal thrombophlebitis of the ovarian veins are described and the literature is reviewed. By means of computer tomography, it has become possible for the first time to make the diagnosis of this little-known and frequently missed condition by a non-invasive method. The patient is spared complicated angiographic procedures and possibly also surgery. The typical CT findings consist of: a) a thickened adnexa, b) a circular lesion extending from the adnexa to the hilum of the kidney, c) an obstructed ureter and c) an enlarged uterus. (orig.) [de

Correlative Imaging in a Patient with Cystic Thymoma: CT, MR and PET/CT Comparison

International Nuclear Information System (INIS)

Romeo, Valeria; Esposito, Alfredo; Maurea, Simone; Camera, Luigi; Mainenti, Pier Paolo; Palmieri, Giovannella; Buonerba, Carlo; Salvatore, Marco

2015-01-01

Cystic thymoma is a rare variant of thymic neoplasm characterized by almost complete cystic degeneration with mixed internal structure. We describe a case of a 60 year-old woman with a cystic thymoma studied with advanced tomographic imaging stydies. CT, MRI and PET/CT with 18 F-FDG were performed; volumetric CT and MRI images provided better anatomic evaluation for pre-operative assessment, while PET/CT was helpful for lesion characterization based on 18 F-FDG uptake. Although imaging studies are mandatory for pre-operative evaluation of cystic thymoma, final diagnosis still remains surgical. A 60-year-old woman with recent chest pain and no history of previous disease was admitted to our departement to investigate the result of a previous chest X-ray that showed bilateral mediastinal enlargement; for this purpose, enhanced chest CT scan was performed using a 64-rows scanner (Toshiba, Aquilion 64, Japan) before and after intravenous bolus administration of iodinated non ionic contrast agent; CT images demonstrated the presence of a large mediastinal mass (11×8 cm) located in the anterior mediastinum who extended from the anonymous vein to the cardio-phrenic space, compressing the left atrium and causing medium lobe atelectasis; bilateral pleural effusion was also present. In conclusion, correlative imaging plays a foundamental role for the diagnostic evaluation of patient with cystic thymoma. In particular, volumetric CT and MRI studies can provide better anatomic informations regarding internal structure and local tumor spread for pre-operative assessment. Conversely, metabolic imaging using 18 F-FDG PET/CT is helpful for lesion characterization differentiating benign from malignant lesion on the basis of intense tracer uptake. The role of PET/MRI is still under investigation. However, final diagnosis still remains surgical even though imaging studies are mandatory for pre-operative patient management

On Importance of Rows for Decision Tables

KAUST Repository

AbouEisha, Hassan M.; Azad, Mohammad; Moshkov, Mikhail

2017-01-01

In this paper, we propose a method for the evaluation of importance of rows for decision tables. It is based on indirect information about changes in the set of reducts after removing the considered row from the table. We also discuss results of computer experiments with decision tables from UCI Machine Learning Repository.

On Importance of Rows for Decision Tables

KAUST Repository

AbouEisha, Hassan M.

2017-06-21

In this paper, we propose a method for the evaluation of importance of rows for decision tables. It is based on indirect information about changes in the set of reducts after removing the considered row from the table. We also discuss results of computer experiments with decision tables from UCI Machine Learning Repository.

Automatic assessment of coronary artery calcium score from contrast-enhanced 256-row coronary computed tomography angiography.

Science.gov (United States)

Rubinshtein, Ronen; Halon, David A; Gaspar, Tamar; Lewis, Basil S; Peled, Nathan

2014-01-01

The coronary artery calcium score (CS), an independent predictor of cardiovascular events, can be obtained from a stand-alone nonenhanced computed tomography (CT) scan (CSCT) or as an additional nonenhanced procedure before contrast-enhanced coronary CT angiography (CCTA). We evaluated the accuracy of a novel fully automatic tool for computing CS from the CCTA examination. One hundred thirty-six consecutive symptomatic patients (aged 59 ± 11 years, 40% female) without known coronary artery disease who underwent both 256-row CSCT and CCTA were studied. Original scan reconstruction (slice thickness) was maintained (3 mm for CSCT and 0.67 mm for CCTA). CS was computed from CCTA by an automatic tool (COR Analyzer, rcadia Medical Imaging, Haifa, Israel) and compared with CS results obtained by standard assessment of nonenhanced CSCT (HeartBeat CS, Philips, Cleveland, Ohio). We also compared both methods for classification into 5 commonly used CS categories (0, 1 to 10, 11 to 100, 101 to 400, >400 Agatston units). All scans were of diagnostic quality. CS obtained by the COR Analyzer from CCTA classified 111 of 136 (82%) of patients into identical categories as CS by CSCT and 24 of remaining 25 into an adjacent category. Overall, CS values from CCTA showed high correlation with CS values from CSCT (Spearman rank correlation = 0.95, p automatically computed from 256-row CCTA correlated highly with standard CS values obtained from nonenhanced CSCT. CS obtained directly from CCTA may obviate the need for an additional scan and attendant radiation. Copyright © 2014 Elsevier Inc. All rights reserved.

Radiation doses in head CT examinations in Serbia: comparison among different CT units

International Nuclear Information System (INIS)

Arandjic, D.; Ciraj-Bjelac, O.; Bozovic, P.; Stankovic, J.; Hadnadjev, D.; Stojanovic, S.

2012-01-01

A rapid increase in number of Computed Tomography (CT) examinations has been observed world wide. As haed CT is the most frequent CT examination, the purpose of this study was to collect and analyse patient doses in children and adults in different CT units for this procedure. The study included 8 CT units from three manufacturers (Siemens, Toshiba and General Electric). Data for adults and pediatric patients were collected in terms of CTDIvol and DLP values. The doses were estimated as a mean value of 10 patients on each CT unit. For pediatrics, doses were collected for four age groups (0-1year, >1-5years, >5-10years and >10-15years). Comparing different manufacturers and the same number of detector rows it was observed that, in case of 16 slices units, doses were very similar on Siemens and General Electric scanner. CTDIvol and DLP on Siemens scanner were 60 mGy and 1066 mGy·cm, respectively, while on General Electric those values were 66 mGy and 1050 mGy·cm. However, this trend was not observed in case of 64 slices units. CTDIvol and DLP values collected on Toshiba were much higher (177 mGy and 2109 mGy·cm) than in case of Siemens scanner (59 mGy and 1060 mGy·cm). Doses on 16 and 64 slices Siemens scanners were very similar, while on 4 slices were higher. Except in two units, doses were were in line with DRLs. In case of pediatrics, doses increase with patient age and again Siemens scanner showed the lowest values while the highest were observed on Toshiba. (authors)

Rowe's Argument from Improvability | Almeida | Philosophical Papers

African Journals Online (AJOL)

William Rowe has argued that if there is an infinite sequence of improving worlds then an essentially perfectly good being must actualize some world in the sequence and must not actualize any world in the sequence. Since that is impossible, there exist no perfectly good beings. I show that Rowe's argument assumes that ...

Evaluation of multiple trauma victims with 16-row multidetector CT (MDCT): a time analysis; Anwendung der 16-Zeilen-Mehrdetektor-CT in der Initialdiagnostik beim Polytrauma: Eine Zeitanalyse

Energy Technology Data Exchange (ETDEWEB)

Heyer, C.M.; Nicolas, V. [Bochum Univ. (Germany). Inst. fuer Diagnostische Radiologie, Interventionelle Radiologie und Nuklearmedizin; Rduch, G.J. [Bochum Univ. (Germany). Klinik fuer Chirurgie; Wick, M.; Muhr, G. [Bochum Univ. (Germany). Medizinische Klinik III, Pneumologie, Allergologie und Schlafmedizin; Bauer, T.T. [Berufsgenossenschaftliche Kliniken Bergmannsheil, Ruhr-Univ. Bochum (Germany)

2005-12-15

Purpose: Description and time analysis of a 16-row MDCT protocol in the evaluation of multiple trauma patients considering transport, time of scanning, patient positioning, image reconstruction, and image interpretation. Materials and methods: Between May and December 2004, 60 multiple trauma patients underwent 16-row MDCT (Sensation, Siemens, Erlangen, Germany). The protocol included serial scanning of the head, spiral scanning of the cervical spine and contrast-enhanced spiral scanning of the thorax/abdomen with multiplanar reformations (MPR) of the thoracic/lumbar spine and the pelvis. All time intervals including transport, patient positioning, scanning, duration of MPR, total time in the examination room, and time to first and final image interpretation were prospectively evaluated. Furthermore, patient characteristics, trauma profiles, and mortality rates were recorded. Results: 46 male and 14 female patients (mean age 43.6 years) were enrolled in the study. Time analysis of 16-row MDCT revealed the following results (mean time standard deviation): Emergency room treatment and transport 19.2{+-}6.7 min, patient positioning 16.5{+-}6.5 min, scan duration 8.0{+-}3.3 min, total time in examination room 24.5{+-}7.2 min, image reconstruction including MPR 32.0{+-}16.4 min, and time of first (16.4{+-}4.7 min) and final image interpretation (82.5{+-}30.4 min). Trauma profiles revealed thoracic injuries in 35/60 patients (58.3%), head injuries in 23/60 patients (38.3%), abdominal injuries in 15/60 patients (25.0%), injuries of the cervical (9/60 patients, 15.0%), thoracic (12/60 patients, 20.0%), and lumbar spine (19/60 patients, 31.7%), pelvic injuries in 13/60 patients (21.7%), and injuries of extremities in 39/60 patients (65.0%). The mortality rate was 21.7%. (orig.)

Comparison of intravascular ultrasound and angiographic assessement of coronary reference segment size in patients with type 2 diabetes mellitus

DEFF Research Database (Denmark)

Jensen, Lisette Okkels; Thayssen, Per; Mintz, Gary S

2008-01-01

During percutaneous coronary intervention, the reference segment is assessed angiographically. This report described the discrepancy between angiographic and intravascular ultrasound (IVUS) assessment of reference segment size in patients with type 2 diabetes mellitus. Preintervention IVUS was used...... to study 62 de novo lesions in 41 patients with type 2 diabetes mellitus. The lesion site was the image slice with the smallest lumen cross-sectional area (CSA). The proximal and distal reference segments were the most normal-looking segments within 5 mm proximal and distal to the lesion. Plaque burden...... was measured as plaque CSA/external elastic membrane (EEM) CSA. Using IVUS, the reference lumen diameter was 2.80 +/- 0.42 mm and the reference EEM diameter was 4.17 +/- 0.56 mm. The angiographic reference diameter was 2.63 +/- 0.36 mm. Mean difference between the IVUS EEM diameter and angiographic reference...

Usefulness of Reformatted CT Rib Series in Patients with Thoracic Trauma

Energy Technology Data Exchange (ETDEWEB)

Moon, Sung Nam; Park, Seong Hoon; Kim, Na Hyung; Juhng, Seon Kwan; Yoon, Kwon Ha [Dept. of Radiology and Institute for Radiological Imaging Science, Wonkwang University School of Medicine, Iksan (Korea, Republic of); Bang, Dong Ho [Dept. of Radiology, Aerospace Medical Center, Cheongwon (Korea, Republic of)

2013-01-15

To assess the value of adding a reformatted computed tomography (CT) rib series to transversely reconstructed CT imaging in the evaluation of rib fractures in patients with suspected traumatic thoracic injuries. One hundred consecutive patients with suspected traumatic thoracic injuries underwent 128-section multi-detector row CT. Transverse CT images with 5-mm-thick sections were reconstructed and rib series were reformatted using isotropic vogel data. Three independent radiologists, who were blinded to the data, interpreted the CT scans at 2 sessions with a 4-week interval between the sessions. Only transverse CT images were reviewed at the first session. At the second session, the CT images were reviewed along with the reformatted CT rib series. The following parameters were analyzed: receiver operating characteristic (Roc) curve, pairwise comparisons of Roc curves, sensitivity, specificity, positive predictive value, and negative predictive value. There were 153 rib fractures in 29 patients. The level of the area under the Roc curve, Az improved for all observers. The diagnostic sensitivity and specificity of each observer tended to improve in the second session. The mean confidence scores for all observers of patients with rib fractures improved significantly in the second session. A reformatted CT rib series together with transverse CT scan is useful for the evaluation of rib fracture.

Monitoring of performance and training in rowing.

Science.gov (United States)

Mäestu, Jarek; Jürimäe, Jaak; Jürimäe, Toivo

2005-01-01

Rowing is a strength-endurance type of sport and competition performance depends on factors such as aerobic and anaerobic power, physical power, rowing technique and tactics. Therefore, a rower has to develop several capacities in order to be successful and a valid testing battery of a rower has to include parameters that are highly related to rowing performance. Endurance training is the mainstay in rowing. For the 2000 m race, power training at high velocities should be preferred to resistance training at low velocities in order to train more specifically during the off-season. The specific training of the international rower has to be approximately 70% of the whole training time. Several studies have reported different biochemical parameters for monitoring the training of rowers. There is some evidence that plasma leptin is more sensitive to training volume changes than specific stress hormones (e.g. cortisol, testosterone, growth hormone). In rowing, the stress hormone reactions to training volume and/or intensity changes are controversial. The Recovery-Stress Questionnaire for Athletes measures both stress and recovery, and may therefore be more effective than the previously used Borg ratio scale or the Profile of Mood States, which both focus mainly on the stress component. In the future, probably the most effective way to evaluate the training of rowers is to monitor both stress and recovery components at the same time, using both psychometric data together with the biochemical and performance parameters.

Low-tube-voltage (80 kVp) CT aortography using 320-row volume CT with adaptive iterative reconstruction: lower contrast medium and radiation dose

Energy Technology Data Exchange (ETDEWEB)

Chen, Chien-Ming; Chu, Sung-Yu; Hsu, Ming-Yi [Chang Gung University, Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital Linkou, College of Medicine, Taoyuan (China); Liao, Ying-Lan [National Tsing Hua University, Department of Biomedical Engineering and Environmental Sciences, Hsinchu (China); Tsai, Hui-Yu [Chang Gung University, Department of Medical Imaging and Radiological Sciences, College of Medicine, Taoyuan (China); Chang Gung University, Healthy Aging Research Center, Taoyuan (China); Chang Gung University, Department of Medical Imaging and Radiological Sciences, Taoyuan (China)

2014-02-15

To evaluate CT aortography at reduced tube voltage and contrast medium dose while maintaining image quality through iterative reconstruction (IR). The Institutional Review Board approved a prospective study of 48 patients who underwent follow-up CT aortography. We performed intra-individual comparisons of arterial phase images using 120 kVp (standard tube voltage) and 80 kVp (low tube voltage). Low-tube-voltage imaging was performed on a 320-detector CT with IR following injection of 40 ml of contrast medium. We assessed aortic attenuation, aortic attenuation gradient, image noise, contrast-to-noise ratio (CNR), volume CT dose index (CTDI{sub vol}), and figure of merit (FOM) of image noise and CNR. Two readers assessed images for diagnostic quality, image noise, and artefacts. The low-tube-voltage protocol showed 23-31 % higher mean aortic attenuation and image noise (both P < 0.01) than the standard-tube-voltage protocol, but no significant difference in the CNR and aortic attenuation gradients. The low-tube-voltage protocol showed a 48 % reduction in CTDI{sub vol} and an 80 % increase in FOM of CNR. Subjective diagnostic quality was similar for both protocols, but low-tube-voltage images showed greater image noise (P = 0.01). Application of IR to an 80-kVp CT aortography protocol allows radiation dose and contrast medium reduction without affecting image quality. (orig.)

Fourier rebinning algorithm for inverse geometry CT.

Science.gov (United States)

Mazin, Samuel R; Pele, Norbert J

2008-11-01

Inverse geometry computed tomography (IGCT) is a new type of volumetric CT geometry that employs a large array of x-ray sources opposite a smaller detector array. Volumetric coverage and high isotropic resolution produce very large data sets and therefore require a computationally efficient three-dimensional reconstruction algorithm. The purpose of this work was to adapt and evaluate a fast algorithm based on Defrise's Fourier rebinning (FORE), originally developed for positron emission tomography. The results were compared with the average of FDK reconstructions from each source row. The FORE algorithm is an order of magnitude faster than the FDK-type method for the case of 11 source rows. In the center of the field-of-view both algorithms exhibited the same resolution and noise performance. FORE exhibited some resolution loss (and less noise) in the periphery of the field-of-view. FORE appears to be a fast and reasonably accurate reconstruction method for IGCT.

Identification of the segmental artery feeding the anterior spinal artery. Correlation between helical CT and angiography

International Nuclear Information System (INIS)

Nishimura, Jun-ichi; Lee, Jin; Koike, Shigeomi

2005-01-01

We investigated whether identification of the segmental artery feeding the anterior spinal artery (ASA) is possible by single-slice helical CT. Enhanced CT and angiography were performed in 14 patients with retroperitoneal, liver, or bone tumor. A single-slice helical CT scanner with 7 mm collimation and a 1.0 helical pitch was used. Scanning was started 25 to 30 sec after an intravenous injection of 100 ml of contrast medium at a rate of 3.0 ml/sec. We predicted the segmental artery feeding the ASA in all 14 patients using enhanced CT images. In 12 of the 14 patients, the segmental artery feeding the ASA was angiographically identified. In 7 of these 12 patients, the level of the segmental artery feeding the ASA identified on segmental arteriogram was the same level as that predicted by enhanced CT. In the remaining 5 patients, the level of the segmental artery feeding the ASA identified on segmental arteriogram was one level higher or lower than the predicted spinal level. We could identify the segmental artery feeding the ASA by detailed examination and interpretation of single-slice helical CT images. (author)

The pretzel sign: angiographic pattern of tortuous intra-aneurysmal blood flow in a giant serpentine aneurysm.

LENUS (Irish Health Repository)

Fanning, N F

2012-02-03

Giant serpentine aneurysms (GSAs) form a specific subgroup of giant cerebral aneurysms that have pathognomonic angiographic features. We report the angiographic findings of a GSA demonstrating a striking convoluted dynamic flow pattern, which we have called the \\'pretzel sign\\'. The aneurysm was successfully treated by permanent occlusion of the parent vessel using a detachable balloon. GSAs should be identified prior to treatment in view of their particular management requirements.

Paleoradiology: advanced CT in the evaluation of nine Egyptian mummies.

Science.gov (United States)

Hoffman, Heidi; Torres, William E; Ernst, Randy D

2002-01-01

Axial thin-collimation state-of-the-art spiral computed tomography (CT) was combined with sagittal and coronal reformatting, three-dimensional (3D) reconstruction, and virtual "fly-through" techniques to nondestructively study nine Egyptian mummies. These techniques provided important paleopathologic and historical information about mummification techniques, depicted anatomy in the most informative imaging plane, illustrated the soft-tissue preservation and physical appearance of mummies in superb detail, and generated an intriguing virtual tour through hollow mummified remains without harming the specimens themselves. Images generated with these methods can help archaeologists and Egyptologists understand these fascinating members of mankind and can serve as adjunct visual aids for laypersons who are interested in mummies. CT has emerged as the imaging modality of choice for the examination of Egyptian mummies due to its noninvasive cross-sectional nature and inherently superior contrast and spatial resolution. As multi-detector row CT and postprocessing tools evolve, the capabilities and applications of CT will continue to proliferate, attesting to the expanded versatility and utility of CT as a noninvasive research tool in the multidisciplinary study of Egyptian mummies. Copyright RSNA, 2002

The value of regional wall motion abnormalities on gated mycardiac perfusion imaging in perfusion imaging in predicting angiographic stenoses of coronary artery

International Nuclear Information System (INIS)

Yao Lixin; Liu Binbin

2007-01-01

Objective: To determine the possible level of angiographic stenoses of coronary artery at which reversible regional wall motion abnormalities (RWMA) are present on 99m Tc-sestamibi ( 99m Tc-MIBI)-gated myocardial perfusion imaging (MPI). Methods: ninty patients undergoing coronary angiography MPI within two weeks were recruited. A five grades and nine segments marking system was introduced to assess the RWMA and thickening of left ventricles. Results: The sensitivity of reversible RWMA for detecting ≥75% angiographic stenoses was 64%,with a specificity of 95% and positive predictive value of 97%. The presence of reversible RWMA was able to stratify patients with severe angiographic stenoses of 75% or more from those less than 75% with high positive predictive value. A good correlation was noted between the presence of reversible RWMA and the coronary artery jeopardy score. Multivariate analysis showed that the post-stress RWMA and reversible RWMA scores and positive dipyridamole-stress exercise electrocardiogram(ECG) were significant predictors of angiographic severity. Conclusions: Reversible RWMA, as shown by dipyridamole stress 99m Tc-MIBI MPI, is a significant predictor of angiographic disease with very high specificity and adds incremental value to MPI for the assessment of angiographic severity. (authors)

Hereditary haemorrhagic telangiectasia: study of hepatic vascular alterations with multi-detector row helical CT and reconstruction programs; Telangiectasia emorragica ereditaria: TC multidetettore multifasica e programmi di ricostruzione nello studio delle alterazioni vascolari epatiche

Energy Technology Data Exchange (ETDEWEB)

Memeo, Maurizio; Stabile Ianora, Amato Antonio; Scaldapane, Arnaldo; Rotondo, Antonio; Angelelli, Giuseppe [Policlinico Universitario, Bari (Italy). DiMIMP Sezione di Diagnostica per Immagini; Suppressa, Patrizia; Cirulli, Anna; Sabba' , Carlo [Policlinico Universitario, Bari (Italy). Centro Interdipartimentale per lo studio dell' HHT

2005-02-01

Purpose: To evaluate hepatic alterations in patients affected by Hereditary Haemorrhagic Telangiectasia (HHT) by using multidetector row helical CT (MDCT) and new reconstruction programs. Materials and methods: An MDCT multiphasic study of the liver was performed in 105 consecutive patients: 89 considered to be affected by HHT and 16 with suspicion of disease alone. The scan delay was determined by using a test bolus of contrast material. The CT examination was performed with a triphasic technique (double arterial phase and portal venous phase). multiplanar and angiographic reconstructions were then obtained, and the images checked for the presence of shunts, hepatic perfusion disorders, vascular lesions (telangiectasis and large confluent vascular masses), indirect signs of portal hypertension, and anatomical vascular variants. Results: Hepatic vascular alterations were found in 78/105 cases (67/89) patients affected by HHT and 11/16 patients with clinical suspicion alone). Therefore HHT diagnosis was excluded in 5 patients. 78/100 (78%) patients with HHT had intrahepatic vascular alterations: arterioportal shunts in 40/78 (51.2%) arteriosystemic shunts in 16/78 (20.5%) and both shunt types in 22/78 (28.3%). Intraparenchymal perfusion disorders were found in 46/78 (58.9%) patients. Telangiectasis were recognised in 50/78 (64.1%) patients. Large confluent vascular masses (LCVMs) were identified in 20/78 (25.6%) patients. indirect signs of portal hypertension were found in 46/78 (58.9%) cases. Variant hepatic arterial anatomy was present in 38/100 cases (38%). Conclusions: Multiphasic MDCT and the new reconstruction programs enable the identification and characterisation of the complex vascular alterations typical of HHT. [Italian] Scopo: Valutare le alterazioni epatiche nei pazienti affetti da Telangiectasia Emorraica Ereditaria (TEE) utilizzando una TC multidetettore (TCMD) ed in nuovi programmi di ricostruzione. Materiale e metodi: E' stato eseguito uno

Machine learning analysis of binaural rowing sounds

DEFF Research Database (Denmark)

Johard, Leonard; Ruffaldi, Emanuele; Hoffmann, Pablo F.

2011-01-01

Techniques for machine hearing are increasing their potentiality due to new application domains. In this work we are addressing the analysis of rowing sounds in natural context for the purpose of supporting a training system based on virtual environments. This paper presents the acquisition metho...... methodology and the evaluation of different machine learning techniques for classifying rowing-sound data. We see that a combination of principal component analysis and shallow networks perform equally well as deep architectures, while being much faster to train.......Techniques for machine hearing are increasing their potentiality due to new application domains. In this work we are addressing the analysis of rowing sounds in natural context for the purpose of supporting a training system based on virtual environments. This paper presents the acquisition...

Variations of Patient Doses in Interventional Examinations at Different Angiographic Units

International Nuclear Information System (INIS)

Bor, Dogan; Toklu, Tuerkay; Olgar, Turan; Sancak, Tanzer; Cekirge, Saruhan; Onal, Baran; Bilgic, Sadik

2006-01-01

Purpose. We analyzed doses for various angiographic procedures using different X-ray systems in order to assess dose variations. Methods. Dose-area product (DAP), skin doses from thermoluminescent dosimeters and air kerma measurements of 308 patients (239 diagnostic and 69 interventional) were assessed for five different angiographic units. All fluoroscopic and radiographic exposure parameters were recorded online for single and multiprojection studies. Radiation outputs of each X-ray system were also measured for all the modes of exposure using standard protocols for such measurements. Results. In general, the complexity of the angiographic procedure was found to be the most important reason for high radiation doses. Skill of the radiologist, management of the exposure parameters and calibration of the system are the other factors to be considered. Lateral cerebral interventional studies carry the highest risk for deterministic effects on the lens of the eye. Effective doses were calculated from DAP measurements and maximum fatal cancer risk factors were found for carotid studies. Conclusions. Interventional radiologists should measure patient doses for their examinations. If there is a lack of necessary instrumentation for this purpose, then published dose reports should be used in order to predict the dose levels from some of the exposure parameters. Patient dose information should include not only the measured quantity but also the measured radiation output of the X-ray unit and exposure parameters used during radiographic and fluoroscopic exposures

Single- and double-row repair for rotator cuff tears - biology and mechanics.

Science.gov (United States)

Papalia, Rocco; Franceschi, Francesco; Vasta, Sebastiano; Zampogna, Biagio; Maffulli, Nicola; Denaro, Vincenzo

2012-01-01

We critically review the existing studies comparing the features of single- and double-row repair, and discuss suggestions about the surgical indications for the two repair techniques. All currently available studies comparing the biomechanical, clinical and the biological features of single and double row. Biomechanically, the double-row repair has greater performances in terms of higher initial fixation strength, greater footprint coverage, improved contact area and pressure, decreased gap formation, and higher load to failure. Results of clinical studies demonstrate no significantly better outcomes for double-row compared to single-row repair. Better results are achieved by double-row repair for larger lesions (tear size 2.5-3.5 cm). Considering the lack of statistically significant differences between the two techniques and that the double row is a high cost and a high surgical skill-dependent technique, we suggest using the double-row technique only in strictly selected patients. Copyright © 2012 S. Karger AG, Basel.

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)

Changes in CT angiographic opacification of porcine coronary artery wall with patchy altered flow in vasa vasorum.

Science.gov (United States)

Moritz, Regina; Anderson, Jill L; Vercnocke, Andrew J; Wentz, Robert J; Ritman, Erik L

2013-08-01

To evaluate the potential of whole-body CT to detect localized areas of decreased or increased vascularity in coronary arterial walls. We used both microsphere embolization of coronary artery vasa vasorum to generate small areas of hypoperfusion and surrounding hyperperfusion of the arterial wall and diet-induced hypercholesterolemia. As a stimulus for localized angiogenesis, such as occurs in early plaque formation in the coronary arterial wall, microspheres were injected selectively into the LAD coronary artery lumens of anesthetized pigs. Fourteen pigs (acute) then had a segment of their LAD harvested during injection of contrast medium and snap-frozen for subsequent cryo-static micro-CT. An additional thirteen pigs (chronic) were allowed to recover, fed a high cholesterol diet and 3 months later were again anesthetized and a segment of the LAD artery harvested and scanned. The spatial distribution of the contrast agent within the arterial wall was measured in contiguous micro-CT images at right angles to the lumen axis with the area of wall in each cross-sectional image being approximately (0.1 mm)(3) in size. In the acute animals there were no localized areas of increased contrast around the hypoperfused embolized perfusion territories in the arterial wall, but in the chronic animals the hypoperfused areas were surrounded by increased contrast. These results suggest that CT might be able to detect localized regions of increased vascularity in the arterial wall as an indicator of early atherosclerotic stimulation of vasa vasorum proliferation.

The effects of misinterpretation of an artefact on multidetector row CT scans in children

Energy Technology Data Exchange (ETDEWEB)

Du Plessis, Anne-Marie; Theron, Salomine; Andronikou, Savvas [University of Stellenbosch, Radiology Department, Tygerberg Hospital, Cape Town (South Africa)

2009-02-15

Artefacts reflect problems with radiographic technique rather than true pathology. These may be misinterpreted as pathology with serious consequences. An artefact caused such problems in one paediatric imaging department. To determine the incidence, and consequences of misinterpretation, of a CT artefact in a paediatric imaging department. A retrospective review of images and reports of paediatric CT scans over a set period with a known artefact was performed. Reports were correlated with reviewers' evaluation of the presence of artefact and reviewed for correct identification of artefact, misinterpretation as pathology, and action taken as a result. A total of 74 CT scans had been performed over the study period and an artefact detected by reviewers on 32 (43%). Six (18.75%) of these were misinterpreted as pathology, of which three (9.4%) were reported as tuberculous granulomas, two (6.2%) as haemorrhages and one (3.1%) as an unknown hyperdensity. Two patients (6.2%) had subsequent MRI studies performed, and treatment for tuberculosis was continued in one patient (3.1%). No initial report identified the artefact. One-fifth of the scans with the artefact were misinterpreted as pathology and half of these misinterpretations led to further action. Artefacts result in false diagnoses and unnecessary investigations; vigilance is needed. (orig.)

Influence of gating phase selection on the image quality of coronary arteries in multidetector row computed tomography

International Nuclear Information System (INIS)

Laskowska, K.; Marzec, M.; Serafin, Z.; Nawrocka, E.; Lasek, W.; WWisniewska-Szmyt, J.; Kubica, J.

2005-01-01

Motion artifacts caused by cardiac movement disturb the imaging of coronary arteries with multidetector-row spiral computed tomography. The aim of this study was to determine the phase of the heart rate which provides the best quality of coronary artery imaging in retrospective ECG-gated CT. Although 75% is usually the best reconstruction phase, the optimal phase should be established individually for the patient, artery, segment, and type of tomograph for the best imaging quality. Forty-five cardiac CT angiograms of 26 patients were retrospectively evaluated. The examinations were performed with a 4-detector-row tomograph. ECG-gated retrospective reconstructions were relatively delayed at 0%, 12.5%, 25%, 37.5%, 50%, 62.5%, 75%, and 87.5% of the cardiac cycle. Selected coronary arteries of the highest diagnostic quality were estimated in the eight phases of the cardiac cycle. Only arteries of very high image quality were selected for analysis: left coronary artery trunks (44 cases, incl. 37 stented), anterior interventricular branches (36, incl. 3 stented), circumflex branches (16), right coronary rtery branches (23), and posterior interventricular branches (4). The reconstruction phase had a statistically significant impact on the quality of imaging (p < 0.0003). Depending on the case, optimal imaging was noted in various phases, except in the 12.5 % phase. The 75% phase appeared to be the best of all those examined (p < 0.05), both in the group of arteries without stents (p < 0.0006) and in those stented (p < 0.05). In some cases of repeated examinations the best phases differed within the same patient. (author)

Diagnostic accuracy and utility of coronary CT angiography with consideration of unevaluable results: A systematic review and multivariate Bayesian random-effects meta-analysis with intention to diagnose

Energy Technology Data Exchange (ETDEWEB)

Menke, Jan [University Medical Center Goettingen, Institute for Diagnostic and Interventional Radiology, Goettingen (Germany); Kowalski, Joerg [Dr. Lauterbach-Klinik, Department of Cardiology, Bad Liebenstein (Germany)

2016-02-15

To meta-analyze diagnostic accuracy, test yield and utility of coronary computed tomography angiography (CCTA) in coronary artery disease (CAD) by an intention-to-diagnose approach with inclusion of unevaluable results. Four databases were searched from 1/2005 to 3/2013 for prospective studies that used 16-320-row or dual-source CTs and provided 3 x 2 patient-level data of CCTA (positive, negative, or unevaluable) versus catheter angiography (positive or negative) for diagnosing ≥50 % coronary stenoses. A Bayesian multivariate 3 x 2 random-effects meta-analysis considered unevaluable CCTAs. Thirty studies (3422 patients) were included. Compared to 16-40 row CT, test yield and accuracy of CCTA has significantly increased with ≥64-row CT (P < 0.05). In ≥64-row CT, about 2.5 % (95 %-CI, 0.9-4.8 %) of diseased patients and 7.5 % (4.5-11.2 %) of non-diseased patients had unevaluable CCTAs. A positive likelihood ratio of 8.9 (6.1-13.5) indicated moderate suitability for identifying CAD. A negative likelihood ratio of 0.022 (0.01-0.04) indicated excellent suitability for excluding CAD. Unevaluable CCTAs had an equivocal likelihood ratio of 0.42 (0.22-0.71). In the utility analysis, CCTA was useful at intermediate pre-test probabilities (16-70 %). CCTA is useful at intermediate CAD pre-test probabilities. Positive CCTAs require verification to confirm CAD, unevaluable CCTAs require alternative diagnostics, and negative CCTAs exclude obstructive CAD with high certainty. (orig.)

Feasibility and Safety of Transradial Arterial Approach for Simultaneous Right and Left Vertebral Artery Angiographic Studies and Stenting

International Nuclear Information System (INIS)

Yip, H.-K.; Youssef, Ali A.; Chang, W.-N.; Lu, C.-H.; Yang, C.-H.; Chen, S.-M.; Wu, C.-J.

2007-01-01

Objectives. This study investigated whether the transradial artery (TRA) approach using a 6-French (F) Kimny guiding catheter for right vertebral artery (VA) angiographic study and stenting is safe and effective for patients with significant VA stenosis. Background. The TRA approach is commonly performed worldwide for both diagnostic cardiac catheterization and catheter-based coronary intervention. However, to our knowledge, the safety and feasibility of left and right VA angiographic study and stenting, in the same procedure, using the TRA approach for patients with brain ischemia have not been reported. Methods. The study included 24 consecutive patients (22 male, 2 female; age, 63-78 years). Indications for VA angiographic study and stenting were (1) prior stroke or symptoms related to vertebrobasilar ischemia and (2) an asymptomatic but vertebral angiographic finding of severe stenosis (>70%). A combination of the ipsilateral and retrograde-engagement technique, which involved a looping 6-F Kimny guiding catheter, was utilized for VA angiographic study. For VA stenting, an ipsilateral TRA approach with either a Kimny guiding catheter or a left internal mammary artery guiding catheter was utilized in 22 patients and retrograde-engagement technique in 2 patients. Results. A technically successful procedure was achieved in all patients, including left VA stenting in 15 patients and right VA stenting in 9 patients. The mean time for stenting (from engagement to stent deployment) was 12.7 min. There were no vascular complications or mortality. However, one patient suffered from a transient ischemic attack that resolved within 3 h. Conclusion. We conclude that TRA access for both VA angiographic study and VA stenting is safe and effective, and provides a simple and useful clinical tool for patients unsuited for femoral arterial access

A Spider That Lays Its Eggs in Rows

Directory of Open Access Journals (Sweden)

Robert L. Edwards

2000-01-01

Full Text Available The small (2.5-3.0 mm, colorful metine spider, Homalometa nigritarsis Simon 1897, Family Tetragnathidae, has previously been reported from northern Mexico, Panama and the southern islands of the Lesser Antilles (Levi 1986. In the rain forest of northeastern Puerto Rico it is most frequently found with webbing on the larger outer concave surfaces of pendulous leaves. H. nigritarsis typically makes a circular, relatively flat retreat within which the female deposits two parallel rows of naked eggs. The rows are produced at intervals; as one row hatches another replaces it shortly thereafter. Evidence of up to four generations of rows has been observed. Above the retreat, and closely aligned with it, the spider builds a nearly invisible, delicate orb web, typically from edge to edge of the leaf (Fig. 1a and b. While retaining the traditional orb-web, H. nigritarsis has adopted a unique habitat and set of life history features.

Computed tomographic diagnosis for hepatofugal collaterals in portal hypertension. Comparative study of CT with percutaneous transhepatic portography

Energy Technology Data Exchange (ETDEWEB)

Iida, Akihiko; Sano, Akira; Imanaka, Kazufumi; Nishizawa, Sadahiko; Sasai, Keisuke

1984-08-01

This paper deals with the diagnostic capability of CT scan for hepatofugal collaterals in 22 patients with portal hypertension. The patients studied were those who underwent percutaneous transhepatic portography (PTP) and CT scan within a short period. Each collateral vein demonstrated by PTP was classified into three grades according to its caliber (d): (1) Grade I, d<5mm, (2) Grade II, 5mmCT images was analyzed comparatively. Most collaterals in Grade I failed to demonstrate on CT images, while Grade II and III well coincided with CT images, at the rate of 64% and 100% respectively. CT features of these vascular structures showed multiformity: rounded, ovoid comma-shaped, tubular or beaded, etc. To get an accurate diagnosis, each image must be analyzed together with the adjacent upper and lower ones on the fully-performed contrast enhancement technique. Image deterioration of CT was concerned with Partial Volume Phenomenon for small vessels, and motion artifacts produced by intestinal peristalses, cardiac beats and occasionally by difficulty of breath holding. In spite of such diagnostic Iimitation, CT scan provides much qualified images than conventional angiographic procedures in evaluating hepatofugal collaterals.

Improving Spectral Results Using Row-by-Row Fourier Transform of Spatial Heterodyne Raman Spectrometer Interferogram.

Science.gov (United States)

Barnett, Patrick D; Strange, K Alicia; Angel, S Michael

2017-06-01

This work describes a method of applying the Fourier transform to the two-dimensional Fizeau fringe patterns generated by the spatial heterodyne Raman spectrometer (SHRS), a dispersive interferometer, to correct the effects of certain types of optical alignment errors. In the SHRS, certain types of optical misalignments result in wavelength-dependent and wavelength-independent rotations of the fringe pattern on the detector. We describe here a simple correction technique that can be used in post-processing, by applying the Fourier transform in a row-by-row manner. This allows the user to be more forgiving of fringe alignment and allows for a reduction in the mechanical complexity of the SHRS.

An aerial radiological survey of the Yankee Rowe Nuclear Power Station and surrounding area, Rowe, Massachusetts

International Nuclear Information System (INIS)

Boyns, P.K.; Bluitt, C.M.

1993-09-01

An aerial radiological survey was conducted over the Yankee Rowe Nuclear Power Station in Rowe, Massachusetts, during the period August 17--24, 1989. The survey was conducted at an altitude of 300 feet (91 meters) over an 87-square-mile (225-square-kilometer) area centered on the power station. The purpose of the survey was to document the terrestrial gamma radiation environment of the Yankee Rowe Power Station and the surrounding area. The results of the aerial survey are reported as inferred gamma radiation exposure rates at 1 meter above ground level in the form of a contour map. Outside the plant boundary, exposure rates were found to vary between 6 and 10 microroentgens per hour (μR/h) and were attributed to naturally-occurring uranium, thorium, and radioactive potassium gamma emitters. The aerial data were compared to ground-based ''benchmark'' exposure rate measurements and radionuclide assays of soil samples obtained within the survey boundary. The ground-based measurements were found to be in good agreement with those inferred from the aerial measuring system

Intraoperative CT with integrated navigation system in spinal neurosurgery

International Nuclear Information System (INIS)

Zausinger, S.; Heigl, T.; Scheder, B.; Schnell, O.; Tonn, J.C.; Uhl, E.; Morhard, D.

2007-01-01

For spinal surgery navigational system images are usually acquired before surgery with patients positioned supine. The aim of this study was to evaluate prospectively navigated procedures in spinal surgery with data acquisition by intraoperative computed tomography (iCT). CT data of 38 patients [thoracolumbar instability (n = 24), C1/2 instability (n = 6), cervicothoracic stabilization (n = 7), disk herniation (n = 1)] were acquired after positioning the patient in prone position. A sliding gantry 24 detector row CT was used for image acquisition. Data were imported to the frameless infrared-based neuronavigation station. A postprocedural CT was obtained to assess the extent of decompression and the accuracy of instrumentation. Intraoperative registration revealed computed accuracy 2 mm in 9/158 screws (5.6%), allowing immediate correction in five screws without any damage to vessels or nerves. There were three transient complications with clinical improvement in all patients. Intraoperative CT in combination with neuronavigation provides high accuracy of screw placement and thus safety for patients undergoing spinal stabilization. The procedure is rapid and easy to perform and - by replacing pre- and postoperative imaging-is not associated with additional exposure to radiation. (orig.)

Quantification of coronary artery calcium on the basis of dual-energy coronary CT angiography.

Science.gov (United States)

Schwarz, Florian; Nance, John W; Ruzsics, Balazs; Bastarrika, Gorka; Sterzik, Alexander; Schoepf, U Joseph

2012-09-01

To evaluate the feasibility of using virtual noncontrast material-enhanced (VNC) computed tomographic (CT) series derived from dual-energy CT imaging studies for coronary artery calcium quantification. This HIPAA-compliant study was institutional review board approved; all patients provided written informed consent. Thirty-six patients prospectively underwent noncontrast-enhanced CT calcium scoring followed by coronary CT angiography performed in dual-energy mode. By using different reconstruction algorithms, three VNC series were generated and evaluated for noise and efficiency of virtual iodine removal. Two readers independently quantified calcium on VNC images and true noncontrast-enhanced conventional calcium scoring series. A leave-one-out cross validation was used to assess the accuracy of calcium score prediction from VNC series by means of linear regression. CT value histograms of the VNC series closely resembled the profile in the true noncontrast-enhanced series. There was excellent correlation between calcium volumes on the VNC series and true noncontrast-enhanced series on a per-patient (r = 0.94, P VNC series was excellent (r = 0.82). Multiethnic Study of Atherosclerosis rankings that were derived from the predicted calcium scores also showed excellent agreement (intraclass correlation coefficient = 0.909). Coronary artery calcium identification and quantification based on dual-energy coronary CT angiographic studies may obviate the need for dedicated CT calcium scoring studies. © RSNA, 2012

Usefulness of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI): Assessment of morphology and diameter of the superior mesenteric artery (SMA) on multi-planar reconstructed (MPR) images

International Nuclear Information System (INIS)

Woodhams, Reiko; Nishimaki, Hiroshi; Fujii, Kaoru; Kakita, Satoko; Hayakawa, Kazushige

2010-01-01

Objective: The purpose of this study was to assess the efficacy of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI) by analyzing morphology and diameter of superior mesenteric artery (SMA). We assessed whether MDCT was as useful as angiography for the diagnosis of NOMI. Materials and methods: Four patients who were diagnosed with NOMI were retrospectively analyzed. All patients had 8-row MDCT followed by laparotomy. Two of them underwent angiography after MDCT. The morphology and diameter of SMA of these cases was analyzed on multi-planar reconstructed (MPR) images. The mean diameter of SMA of NOMI cases was compared to that of 13 control cases. Results: MPR images of all NOMI cases showed irregular narrowing of the SMA, spasm of the arcades of SMA, and poor demonstration of intramural vessels. MPR images of two patients who had angiography were concordant with their angiograms. The mean diameter of SMA of NOMI patients was 3.4 ± 1.1 mm, which was statistically smaller than that of 13 control patients, 6.0 ± 1.5 mm (P < 0.05, Wilcoxon rank sum tests). Conclusion: Angiography has been recognized essential for the diagnosis of NOMI. This study shows the possibility of MDCT to be an equivalently useful modality compared to angiography for the diagnosis of NOMI by interpreting morphologic appearance and diameter of SMA. Introduction of MDCT in the decision tree of NOMI treatment may bring the benefit of prompt diagnosis and subsequent early and efficient initiation of therapy, which may improve the mortality.

Automatic crop row detection from UAV images

DEFF Research Database (Denmark)

Midtiby, Henrik; Rasmussen, Jesper

are considered weeds. We have used a Sugar beet field as a case for evaluating the proposed crop detection method. The suggested image processing consists of: 1) locating vegetation regions in the image by thresholding the excess green image derived from the orig- inal image, 2) calculate the Hough transform......Images from Unmanned Aerial Vehicles can provide information about the weed distribution in fields. A direct way is to quantify the amount of vegetation present in different areas of the field. The limitation of this approach is that it includes both crops and weeds in the reported num- bers. To get...... of the segmented image 3) determine the dominating crop row direction by analysing output from the Hough transform and 4) use the found crop row direction to locate crop rows....

The zero-wall puncture: a novel angiographic puncture technique with substantial benefits

International Nuclear Information System (INIS)

Leswick, D.A.; Szkup, P.; Stoneham, G.W.

2005-01-01

Medical education can be busy, exhausting, and stressful, with potential adverse effects on trainees' physical and mental health. Radiology residency is no exception. In addition to increased daily workload and study requirements, Canadian radiology residents are performing a diverse and increasing number of emergent diagnostic examinations after hours. In an attempt to improve resident self-worth and efficiency during angiographic rotations, we investigated the effects of a novel angiographic puncture procedure on various resident lifestyle indexes. Standard techniques for accessing the femoral artery are either the single-wall puncture or double-wall puncture (Seldinger technique). Both of these techniques are widely known and practiced. Following procedure completion, hemostasis must be achieved at the puncture site. This has traditionally required manual compression at the puncture site, which may require 15 to 20 minutes. At our institution the standard policy is that 'whoever makes the puncture, compresses the groin,' also known as 'you broke it, you fix it'. This has prompted our industrious resident complement to develop a novel, previously undescribed, angiographic puncture technique known as the 'zero-wall puncture technique.' Preliminary unpublished results from our institution show that when residents employ the zero-wall puncture technique the attending staff radiologist subsequently both performs the puncture and compresses the groin at the end of the procedure. We investigated the effect of zero-wall puncture on various resident lifestyle indexes. (author)

Focal changes of the spleen in one case of Gaucher disease - assessed by ultrasonography, CT, MRI and angiography

International Nuclear Information System (INIS)

Aspestrand, F.; Charania, B.; Scheel, B.; Kolmannskog, F.; Jacobsen, M.

1989-01-01

Focal lesions of the spleen in one case of Gaucher disease are demonstrated by ultrasonography, CT, MRI and angiography. The sonographic and angiographic features differ from the findings presented in previous reports. The Gaucher manifestations in the spleen as demonstrated by CT, do not seem to have been reported previously. An earlier report on the MR findings in the liver and spleen in this disease did not disclose any focal abnormalities. In this case, ultrasonography and MRI revealed a targetlike configuration of the focal lesions. An attempt is made to analyze the more complex patterns disclosed by MRI against the background of the manifestations by the other imaging modalities and previous reports. (orig.) [de

Don't rock the boat: how antiphase crew coordination affects rowing.

Directory of Open Access Journals (Sweden)

Anouk J de Brouwer

Full Text Available It is generally accepted that crew rowing requires perfect synchronization between the movements of the rowers. However, a long-standing and somewhat counterintuitive idea is that out-of-phase crew rowing might have benefits over in-phase (i.e., synchronous rowing. In synchronous rowing, 5 to 6% of the power produced by the rower(s is lost to velocity fluctuations of the shell within each rowing cycle. Theoretically, a possible way for crews to increase average boat velocity is to reduce these fluctuations by rowing in antiphase coordination, a strategy in which rowers perfectly alternate their movements. On the other hand, the framework of coordination dynamics explicates that antiphase coordination is less stable than in-phase coordination, which may impede performance gains. Therefore, we compared antiphase to in-phase crew rowing performance in an ergometer experiment. Nine pairs of rowers performed a two-minute maximum effort in-phase and antiphase trial at 36 strokes min(-1 on two coupled free-floating ergometers that allowed for power losses to velocity fluctuations. Rower and ergometer kinetics and kinematics were measured during the trials. All nine pairs easily acquired antiphase rowing during the warm-up, while one pair's coordination briefly switched to in-phase during the maximum effort trial. Although antiphase interpersonal coordination was indeed less accurate and more variable, power production was not negatively affected. Importantly, in antiphase rowing the decreased power loss to velocity fluctuations resulted in more useful power being transferred to the ergometer flywheels. These results imply that antiphase rowing may indeed improve performance, even without any experience with antiphase technique. Furthermore, it demonstrates that although perfectly synchronous coordination may be the most stable, it is not necessarily equated with the most efficient or optimal performance.

Relationship between Angiographic Results and Morphology in Sidewall Intracranial Aneurysms after Stent-Assisted Coil Embolization.

Science.gov (United States)

Nii, Kouhei; Aikawa, Hiroshi; Tsutsumi, Masanori; Eto, Ayumu; Iko, Minoru; Sakamoto, Kimiya; Inoue, Ritsuro; Mitsutake, Takafumi; Hanada, Hayatsura; Kazekawa, Kiyoshi

2016-03-01

Stent-assisted coil embolization (SACE) is used to address wide-necked or complex aneurysms. However, as they may recanalize after SACE, predictors of recanalization are needed. We investigated the relationship between follow-up angiographic results and the morphology of sidewall (SW) aneurysms in patients treated by SACE. Between September 2010 and September 2014, we performed 80 SACE procedures for SW intracranial aneurysms. Angiographic findings, obtained immediately after the procedure, 3-6 months thereafter, and when aneurysmal recanalization was suspected on MR angiogram scan, were recorded. Morphologically, the SW aneurysms were classified as "outside" (OS) and "partially inside" (PI) based on the curve of the axes of the proximal or distal parent artery with respect to the aneurysmal neck. Follow-up angiographic studies on OS- and PI SW aneurysms were compared. On the initial angiograms, we classified 42 aneurysms as OS and 38 as PI. Immediately after SACE, there was no significant difference in the angiographic findings on OS and PI aneurysms. However, on follow-up angiograms, there was a significant difference in the rate of spontaneous improvement (4 of 42 [OS] versus 21 of 38 [PI], P = .001). We performed additional coil embolization to treat 3 recanalized OS aneurysms. SW aneurysms classified morphologically as PI tended to occlude progressively even after incomplete occlusion by SACE. In contrast, aneurysms classified as OS must be observed carefully after SACE. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

IMPORTANCE OF KNOWING ANGIOGRAPHIC CHARACTERISTICS OF THE TENSOR FASCIAE LATAE VASCULAR STALK

Directory of Open Access Journals (Sweden)

Sladjana Ugrenovic

2006-07-01

Full Text Available Atherosclerosis is the most important and most common type of arteriosclerosis and is a general term for several diseases in which the artery wall becomes thicker and less elastic. The most common location of atherosclerosis occurrence is arteries of lower extremities, while arteries of upper extremities as well as visceral arteries are far less and far rarely affected with this degenerative process.The most frequent ones are occlusive changes on bifurcation of the abdominal aorta (aortoiliac obstructive atherosclerosis “Morbus Leriche”, trunk of the femoral artery and initial part of the popliteal artery (femoropopliteal obstructive atherosclerosis.Angiography, as additional method in medicine, gives the most precise insight into anatomical changes on blood vessels. With intention of estimating the possibility of using a slice (lobe part of the tensor fasciae latae (m. TFL in plastic and reconstructive surgery, we have analyzed 50 angiograms of femoral artery. The first group included Morbus Leriche patients (25 analyzed angiographics, while the second one comprised patients with femoropopliteal segment disease (also 25 analyzed angiographics. With angiographic analysis of the lateral femoral circumflex artery (LCFA and its branch, which is dominant in vascularisation of m. TFL slice, we discovered that the diameter of its source, as well as of its branches, is bigger in cases of femoropopliteal segment disease. Then, the reduction of the source diameter of LCFA and its branches, caused by vascular disease, leads to decreased blood supply of m. TFL, diminishing its quality and limiting its usage in surgery.In Morbus Leriche cases, m. TFL slice cannot be used in plastic and reconstructive surgery, its quality being decreased, due to poor vascularization. In femoropopliteal segment disease cases, thanks to normal blood supply, m. TFL slice can be widely used for reconstructions or covering of defects, especially in inguinal region, which is

The role of SPECT/CT in radioembolization of liver tumours

Energy Technology Data Exchange (ETDEWEB)

Ahmadzadehfar, Hojjat [University Hospital Bonn, Department of Nuclear Medicine, Bonn (Germany); Duan, Heying; Haug, Alexander R.; Hoffmann, Martha [Medical University of Vienna, Department of Biomedical Imaging und Image-guided Therapy, Clinical Division of Nuclear Medicine, Vienna (Austria); Walrand, Stephan [Universite Catholique de Louvain, Nuclear Medicine, Brussels (Belgium)

2014-05-15

Radioembolization (RE) with {sup 90}Y microspheres is a promising catheter-based therapeutic option for patients with unresectable primary and metastatic liver tumours. Its rationale arises from the dual blood supply of liver tissue through the hepatic artery and the portal vein. Metastatic hepatic tumours measuring >3 mm derive 80 - 100 % of their blood supply from the arterial rather than the portal hepatic circulation. Typically, an angiographic evaluation combined with {sup 99m}Tc-macroaggregated albumin ({sup 99m}Tc-MAA) scan precedes therapy to map the tumour feeding vessels as well as to avoid the inadvertent deposition of microspheres in organs other than the liver. Prior to administration of {sup 99m}Tc-MAA, prophylactic coil embolization of the gastroduodenal artery is recommended to avoid extrahepatic deposition of the microspheres. SPECT/CT allows direct correlation of anatomic and functional information in patients with unresectable liver disease. SPECT/CT is recommended to assess intrahepatic distribution as well as extrahepatic gastrointestinal uptake in these patients. Pretherapeutic SPECT/CT is an important component of treatment planning including catheter positioning and dose finding. A post-therapy bremsstrahlung (BS) scan should follow RE to verify the distribution of the administered tracer. BS SPECT/CT imaging enables better localization and definition of intrahepatic and possible extrahepatic sphere distribution and to a certain degree allows posttreatment dosimetry. In this paper we address the usefulness and significance of SPECT/CT in therapy planning and therapy monitoring of RE. (orig.)

The status of appendiceal CT in our hospital

International Nuclear Information System (INIS)

Honda, Yukiko; Nakanishi, Tadashi; Tagawa, Kohei; Akagi, Shinji; Kurisu, Yoshihiro; Ito, Katsuhide

2006-01-01

Images of 188 cases (112 males and 76 females; 5-88 years old, average 36) of patients with suspected appendicitis were retrospectively examined in the document (October 2003-July 2005). CT was conducted by 16-multidetector-row CT apparatus (MDCT) (Somatom Sensation Cardiac, Siemens) and evaluated the disease as positive, equivocal or negative. The number of positive diagnosis was 63, equivocal 5, and negative 120. Forty-four positive patients received the operation, 42 of whom were found to have appendicitis. Two out of 5 equivocal patients underwent the surgery and appendicitis was diagnosed in both. Ten negative patients received the operation through re-examination of their images, 6 of whom were found to have appendicitis. As above MDCT has improved the accuracy of diagnosis of acute appendicitis, indicating its usefulness in this field. (T.I.)

Water as a contrast medium: a re-evaluation using the multidetector-row computed tomography.

Science.gov (United States)

Makarawo, Tafadzwa P; Negussie, Edsa; Malde, Sachit; Tilak, Jacqueline; Gayagoy, Jennifer; Watson, Jenna; Francis, Faiz; Lincoln, Denis; Jacobs, Michael J

2013-07-01

Water as an intraluminal negative contrast medium produces improved image quality with reduced artefact. However, rapid absorption of oral water in the bowel relative to speed and timing of image capturing has limited its clinical application. These findings predate advances in multidetector-row computed tomography (CT). To re-evaluate differences in image quality, we studied image clarity and luminal distention between the same group of patients who received both a pancreas protocol CT (PPCT) that uses oral water and a conventional positive oral contrast scan. We reviewed 66 patients who had previously undergone both a PPCT and an oral contrast abdominal CT. CT images were independently reviewed by two board-certified radiologists who scored degree of hollow viscus distention and visualization of mural detail using a Likert 5-point scale. Results were evaluated by using the Wilcoxon-signed rank test. Student's t test was applied to evaluate the differences in radiation dosage and Spearman's correlational test was used to evaluate interrater correlation between the radiologists. In comparing the mean radiation dosage, there was no statistical difference between the two protocols, and there was good interrater association with ratios of 0.595 and 0.51 achieved for the PPCT and conventional oral scan, respectively. The Wilcoxon signed-rank test showed statistical differences in the stomach (P contrast medium causing better or equal distention in the bowel and better or equal clarity than routine barium contrast. This calls for a need to reconsider the use of water as a contrast medium in clinical practice.

Resonant Quasi-Optical Systems with Multi-Row Periodic Structures

DEFF Research Database (Denmark)

Oleksandr, Rybalko; Rybalko, Yu A.; Buriak, I. A.

2017-01-01

Selective properties of resonant quasi-optical systems with periodical multi-row structures in millimeter wavelength range are described. The possibility of selection fluctuations in the volume of open resonator using double-row periodic elements was shown in the experiment at 70-80 GHz. Advantages...... and possibility of control the energy characteristics of such structures are also described. The obtained experimental data is used to confirm the results of computational analysis previously described in the literature. Implementation of resonant quasi-optical systems with multi-row periodic structures...

Bridging suture makes consistent and secure fixation in double-row rotator cuff repair.

Science.gov (United States)

Fukuhara, Tetsutaro; Mihata, Teruhisa; Jun, Bong Jae; Neo, Masashi

2017-09-01

Inconsistent tension distribution may decrease the biomechanical properties of the rotator cuff tendon after double-row repair, resulting in repair failure. The purpose of this study was to compare the tension distribution along the repaired rotator cuff tendon among three double-row repair techniques. In each of 42 fresh-frozen porcine shoulders, a simulated infraspinatus tendon tear was repaired by using 1 of 3 double-row techniques: (1) conventional double-row repair (no bridging suture); (2) transosseous-equivalent repair (bridging suture alone); and (3) compression double-row repair (which combined conventional double-row and bridging sutures). Each specimen underwent cyclic testing at a simulated shoulder abduction angle of 0° or 40° on a material-testing machine. Gap formation and tendon strain were measured during the 1st and 30th cycles. To evaluate tension distribution after cuff repair, difference in gap and tendon strain between the superior and inferior fixations was compared among three double-row techniques. At an abduction angle of 0°, gap formation after either transosseous-equivalent or compression double-row repair was significantly less than that after conventional double-row repair (p row repair (p = 0.01) at 0° abduction had significantly less difference in gap formation between the superior and inferior fixations than did conventional double-row repair. After the 30th cycle, the difference in longitudinal strain between the superior and inferior fixations at 0° abduction was significantly less with compression double-row repair (2.7% ± 2.4%) than with conventional double-row repair (8.6% ± 5.5%, p = 0.03). Bridging sutures facilitate consistent and secure fixation in double-row rotator cuff repairs, suggesting that bridging sutures may be beneficial for distributing tension equally among all sutures during double-row repair of rotator cuff tears. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B

Intractable Postpartum Bleeding: A Comparison of the Retrospective Analysis of Angiographic Findings and Transcatheter Arterial Embolization According to Delivery Pattern

Energy Technology Data Exchange (ETDEWEB)

Ahn, Eun Jung; Kim, Young Hwan; Kim, Si Hyung; Choi, Jin Soo; Park, Jun Cheol; Kwon, Sang Hun; Jo, Chi Heum; Cha, Soon Do [Keimyung University College of Medicine, Daegu (Korea, Republic of)

2008-12-15

We evaluated the technical aspect and efficacy of transcatheter arterial embolization (TAE) in cases of intractable postpartum bleeding by comparing the angiographic findings women patients according to their delivery pattern. Between July of 2003 and March of 2008, 55 female patients were enrolled in this study. Of the 55 patients, 36 underwent a vaginal delivery (group 1), whereas 19 underwent a cesarean section delivery (group 2). We retrospectively evaluated the angiographic findings and the embolization technique between groups, using a Pearson Chi-Square test. Medical records and telephone interview findings were also reviewed to evaluate the efficacy of TAE and the outcome of fertility. Significantly greater positive angiographic findings were found in group 2 (63.2%) relative to group 1 (30.6%). For positive angiographic findings, except for AVM, the embolization was performed using coil or glue with gelfoam. For the negative angiographic findings or AVM, the gelfoam was the only embolic agent used. In all patients except for one, bleeding stopped after embolization. Major complications occurred in 2 patients only, and included uterine synechia and perforation. All patients except for one recovered after menstruation. In total, four patients became pregnant and one patient delivered a healthy infant. Positive angiographic findings requiring embolization with coil or glue, as well as gelfoam, were more commonly encountered in group 2 than in group 1. Based on the outcome of the study group, TAE is a safe and effective treatment for intractable postpartum bleeding and is also useful for preserving fertility.

Intractable Postpartum Bleeding: A Comparison of the Retrospective Analysis of Angiographic Findings and Transcatheter Arterial Embolization According to Delivery Pattern

International Nuclear Information System (INIS)

Ahn, Eun Jung; Kim, Young Hwan; Kim, Si Hyung; Choi, Jin Soo; Park, Jun Cheol; Kwon, Sang Hun; Jo, Chi Heum; Cha, Soon Do

2008-01-01

We evaluated the technical aspect and efficacy of transcatheter arterial embolization (TAE) in cases of intractable postpartum bleeding by comparing the angiographic findings women patients according to their delivery pattern. Between July of 2003 and March of 2008, 55 female patients were enrolled in this study. Of the 55 patients, 36 underwent a vaginal delivery (group 1), whereas 19 underwent a cesarean section delivery (group 2). We retrospectively evaluated the angiographic findings and the embolization technique between groups, using a Pearson Chi-Square test. Medical records and telephone interview findings were also reviewed to evaluate the efficacy of TAE and the outcome of fertility. Significantly greater positive angiographic findings were found in group 2 (63.2%) relative to group 1 (30.6%). For positive angiographic findings, except for AVM, the embolization was performed using coil or glue with gelfoam. For the negative angiographic findings or AVM, the gelfoam was the only embolic agent used. In all patients except for one, bleeding stopped after embolization. Major complications occurred in 2 patients only, and included uterine synechia and perforation. All patients except for one recovered after menstruation. In total, four patients became pregnant and one patient delivered a healthy infant. Positive angiographic findings requiring embolization with coil or glue, as well as gelfoam, were more commonly encountered in group 2 than in group 1. Based on the outcome of the study group, TAE is a safe and effective treatment for intractable postpartum bleeding and is also useful for preserving fertility

Slide-based ergometer rowing

DEFF Research Database (Denmark)

Vinther, Anders; Alkjær, T; Kanstrup, I-L

2012-01-01

Force production profile and neuromuscular activity during slide-based and stationary ergometer rowing at standardized submaximal power output were compared in 14 male and 8 female National Team rowers. Surface electromyography (EMG) was obtained in selected thoracic and leg muscles along with sy...

Usefulness of angiographic embolization endoscopic metallic clip placement in patient with non-variceal upper gastrointestinal bleeding

Energy Technology Data Exchange (ETDEWEB)

Yoon, Min Jae; Hwang, Cheol Mog; Kim, Ho Jun; Cho, Young Jun; Bae, Seok Hwan [Dept. of Radiology, Konyang University Hospital, Daejeon (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young [Dept. of Radiology, Chungnam National University College of Medicine, Daejeon (Korea, Republic of); Kang, Chae Hoon [Dept. of Radiology, Inje University College of Medicine, Pusan Paik Hospital, Busan (Korea, Republic of)

2013-08-15

The aim of this study is to assess the usefulness of angiographic embolization after endoscopic metallic clip placement around the edge of non-variceal upper gastrointestinal bleeding ulcers. We have chosen 41 patients (mean age, 65.2 years) with acute bleeding ulcers (22 gastric ulcers, 16 duodenal ulcers, 3 malignant ulcers) between January 2010 and December 2012. We inserted metallic clips during the routine endoscopic treatments of the bleeding ulcers. Subsequent transcatheter arterial embolization was performed within 2 hours. We analyzed the angiographic positive rates, angiographic success rates and clinical success rates. Among the 41 patients during the angiography, 19 patients (46%) demonstrated active bleeding points. Both groups underwent embolization using microcoils, N-butyl-cyano-acrylate (NBCA), microcoils with NBCA or gelfoam particle. There are no statistically significant differences between these two groups according to which embolic materials are being used. The bleeding was initially stopped in all patients, except the two who experienced technical failures. Seven patients experienced repeated episodes of bleeding within two weeks. Among them, 4 patients were successful re-embolized. Another 3 patients underwent gastrectomy. Overall, clinical success was achieved in 36 of 41 (87.8%) patients. The endoscopic metallic clip placement was helpful to locate the correct target vessels for the angiographic embolization. In conclusion, this technique reduced re-bleeding rates, especially in patients who do not show active bleeding points.

Usefulness of angiographic embolization endoscopic metallic clip placement in patient with non-variceal upper gastrointestinal bleeding

International Nuclear Information System (INIS)

Yoon, Min Jae; Hwang, Cheol Mog; Kim, Ho Jun; Cho, Young Jun; Bae, Seok Hwan; Shin, Byung Seok; Ohm, Joon Young; Kang, Chae Hoon

2013-01-01

The aim of this study is to assess the usefulness of angiographic embolization after endoscopic metallic clip placement around the edge of non-variceal upper gastrointestinal bleeding ulcers. We have chosen 41 patients (mean age, 65.2 years) with acute bleeding ulcers (22 gastric ulcers, 16 duodenal ulcers, 3 malignant ulcers) between January 2010 and December 2012. We inserted metallic clips during the routine endoscopic treatments of the bleeding ulcers. Subsequent transcatheter arterial embolization was performed within 2 hours. We analyzed the angiographic positive rates, angiographic success rates and clinical success rates. Among the 41 patients during the angiography, 19 patients (46%) demonstrated active bleeding points. Both groups underwent embolization using microcoils, N-butyl-cyano-acrylate (NBCA), microcoils with NBCA or gelfoam particle. There are no statistically significant differences between these two groups according to which embolic materials are being used. The bleeding was initially stopped in all patients, except the two who experienced technical failures. Seven patients experienced repeated episodes of bleeding within two weeks. Among them, 4 patients were successful re-embolized. Another 3 patients underwent gastrectomy. Overall, clinical success was achieved in 36 of 41 (87.8%) patients. The endoscopic metallic clip placement was helpful to locate the correct target vessels for the angiographic embolization. In conclusion, this technique reduced re-bleeding rates, especially in patients who do not show active bleeding points.

Radiation dose assessment in a 320-detector-row CT scanner used in cardiac imaging

International Nuclear Information System (INIS)

Goma, Carles; Ruiz, Agustin; Jornet, Nuria; Latorre, Artur; Pallerol, Rosa M.; Carrasco, Pablo; Eudaldo, Teresa; Ribas, Montserrat

2011-01-01

Purpose: In the present era of cone-beam CT scanners, the use of the standardized CTDI 100 as a surrogate of the idealized CTDI is strongly discouraged and, consequently, so should be the use of the dose-length product (DLP) as an estimate of the total energy imparted to the patient. However, the DLP is still widely used as a reference quantity to normalize the effective dose for a given scan protocol mainly because the CTDI 100 is an easy-to-measure quantity. The aim of this article is therefore to describe a method for radiation dose assessment in large cone-beam single axial scans, which leads to a straightforward estimation of the total energy imparted to the patient. The authors developed a method accessible to all medical physicists and easy to implement in clinical practice in an attempt to update the bridge between CT dosimetry and the estimation of the effective dose. Methods: The authors used commercially available material and a simple mathematical model. The method described herein is based on the dosimetry paradigm introduced by the AAPM Task Group 111. It consists of measuring the dose profiles at the center and the periphery of a long body phantom with a commercial solid-state detector. A weighted dose profile is then calculated from these measurements. To calculate the CT dosimetric quantities analytically, a Gaussian function was fitted to the dose profile data. Furthermore, the Gaussian model has the power to condense the z-axis information of the dose profile in two parameters: The single-scan central dose, f(0), and the width of the profile, σ. To check the energy dependence of the solid-state detector, the authors compared the dose profiles to measurements made with a small volume ion chamber. To validate the overall method, the authors compared the CTDI 100 calculated analytically to the measurement made with a 100 mm pencil ion chamber. Results: For the central and weighted dose profiles, the authors found a good agreement between the

Radiation dose assessment in a 320-detector-row CT scanner used in cardiac imaging

Energy Technology Data Exchange (ETDEWEB)

Goma, Carles; Ruiz, Agustin; Jornet, Nuria; Latorre, Artur; Pallerol, Rosa M.; Carrasco, Pablo; Eudaldo, Teresa; Ribas, Montserrat [Servei de Radiofisica i Radioproteccio, Hospital de la Santa Creu i Sant Pau, Sant Antoni Maria Claret 167, 08025 Barcelona (Spain)

2011-03-15

Purpose: In the present era of cone-beam CT scanners, the use of the standardized CTDI{sub 100} as a surrogate of the idealized CTDI is strongly discouraged and, consequently, so should be the use of the dose-length product (DLP) as an estimate of the total energy imparted to the patient. However, the DLP is still widely used as a reference quantity to normalize the effective dose for a given scan protocol mainly because the CTDI{sub 100} is an easy-to-measure quantity. The aim of this article is therefore to describe a method for radiation dose assessment in large cone-beam single axial scans, which leads to a straightforward estimation of the total energy imparted to the patient. The authors developed a method accessible to all medical physicists and easy to implement in clinical practice in an attempt to update the bridge between CT dosimetry and the estimation of the effective dose. Methods: The authors used commercially available material and a simple mathematical model. The method described herein is based on the dosimetry paradigm introduced by the AAPM Task Group 111. It consists of measuring the dose profiles at the center and the periphery of a long body phantom with a commercial solid-state detector. A weighted dose profile is then calculated from these measurements. To calculate the CT dosimetric quantities analytically, a Gaussian function was fitted to the dose profile data. Furthermore, the Gaussian model has the power to condense the z-axis information of the dose profile in two parameters: The single-scan central dose, f(0), and the width of the profile, {sigma}. To check the energy dependence of the solid-state detector, the authors compared the dose profiles to measurements made with a small volume ion chamber. To validate the overall method, the authors compared the CTDI{sub 100} calculated analytically to the measurement made with a 100 mm pencil ion chamber. Results: For the central and weighted dose profiles, the authors found a good

Vision-GPS Fusion for Guidance of an Autonomous Vehicle in Row Crops

DEFF Research Database (Denmark)

Bak, Thomas

2001-01-01

This paper presents a real-time localization system for an autonomous vehicle passing through 0.25 m wide crop rows at 6 km/h. Localization is achieved by fusion of mea-surements from a row guidance sensor and a GPS receiver. Conventional agricultural practice applies inputs such as herbicide...... at a constant rate ignoring the spatial variability in weed, soil, and crop. Sensing with a guided vehicle allow cost effective mapping of field variability and inputs may be adjusted accordingly. Essential to such a vehicle is real-time localization. GPS allow precise absolute sensing but it is not practical...... to guide the vehicle relative to the crop rows on an absolute coordinate. A row guidance sensor is therefore included to sense the position relative to the rows. The vehicle path in the field is re-planned online in order to allow for crop row irregularities sensed by the row sensor. The path generation...

Validated biomechanical model for efficiency and speed of rowing.

Science.gov (United States)

Pelz, Peter F; Vergé, Angela

2014-10-17

The speed of a competitive rowing crew depends on the number of crew members, their body mass, sex and the type of rowing-sweep rowing or sculling. The time-averaged speed is proportional to the rower's body mass to the 1/36th power, to the number of crew members to the 1/9th power and to the physiological efficiency (accounted for by the rower's sex) to the 1/3rd power. The quality of the rowing shell and propulsion system is captured by one dimensionless parameter that takes the mechanical efficiency, the shape and drag coefficient of the shell and the Froude propulsion efficiency into account. We derive the biomechanical equation for the speed of rowing by two independent methods and further validate it by successfully predicting race times. We derive the theoretical upper limit of the Froude propulsion efficiency for low viscous flows. This upper limit is shown to be a function solely of the velocity ratio of blade to boat speed (i.e., it is completely independent of the blade shape), a result that may also be of interest for other repetitive propulsion systems. Copyright © 2014 Elsevier Ltd. All rights reserved.