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Sample records for 64-detector-row computed tomography

  1. Imaging the pericardium: appearances on ECG-gated 64-detector row cardiac computed tomography

    Science.gov (United States)

    O'Leary, S M; Williams, P L; Williams, M P; Edwards, A J; Roobottom, C A; Morgan-Hughes, G J; Manghat, N E

    2010-01-01

    Multidetector row computed tomography (MDCT) with its high spatial and temporal resolution has now become an established and complementary method for cardiac imaging. It can now be used reliably to exclude significant coronary artery disease and delineate complex coronary artery anomalies, and has become a valuable problem-solving tool. Our experience with MDCT imaging suggests that it is clinically useful for imaging the pericardium. It is important to be aware of the normal anatomy of the pericardium and not mistake normal variations for pathology. The pericardial recesses are visible in up to 44% of non-electrocardiogram (ECG)-gated MDCT images. Abnormalities of the pericardium can now be identified with increasing certainty on 64-detector row CT; they may be the key to diagnosis and therefore must not be overlooked. This educational review of the pericardium will cover different imaging techniques, with a significant emphasis on MDCT. We have a large research and clinical experience of ECG-gated cardiac CT and will demonstrate examples of pericardial recesses, their variations and a wide variety of pericardial abnormalities and systemic conditions affecting the pericardium. We give a brief relevant background of the conditions and reinforce the key imaging features. We aim to provide a pictorial demonstration of the wide variety of abnormalities of the pericardium and the pitfalls in the diagnosis of pericardial disease. PMID:20197434

  2. MR angiography with parallel acquisition for assessment of the visceral arteries: comparison with conventional MR angiography and 64-detector-row computed tomography

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    Sutter, Reto [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Heilmaier, Christina [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Lutz, Amelie M.; Willmann, Juergen K. [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Stanford University School of Medicine, Department of Radiology, Stanford, CA (United States); Weishaupt, Dominik [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Hospital Triemli, Department of Radiology, Zurich (Switzerland); Seifert, Burkhardt [University of Zurich, Biostatistics Unit, Institute of Social and Preventive Medicine, Zurich (Switzerland)

    2009-11-15

    The purpose of the study was to retrospectively compare three-dimensional gadolinium-enhanced magnetic resonance angiography (conventional MRA) with MRA accelerated by a parallel acquisition technique (fast MRA) for the assessment of visceral arteries, using 64-detector-row computed tomography angiography (MDCTA) as the reference standard. Eighteen patients underwent fast MRA (imaging time 17 s), conventional MRA (29 s) and MDCTA of the abdomen and pelvis. Two independent readers assessed subjective image quality and the presence of arterial stenosis. Data were analysed on per-patient and per-segment bases. Fast MRA yielded better subjective image quality in all segments compared with conventional MRA (P = 0.012 for reader 1, P = 0.055 for reader 2) because of fewer motion-induced artefacts. Sensitivity and specificity of fast MRA for the detection of arterial stenosis were 100% for both readers. Sensitivity of conventional MRA was 89% for both readers, and specificity was 100% (reader 1) and 99% (reader 2). Differences in sensitivity between the two types of MRA were not significant for either reader. Interobserver agreement for the detection of arterial stenosis was excellent for fast ({kappa} = 1.00) and good for conventional MRA ({kappa} = 0.76). Thus, subjective image quality of visceral arteries remains good on fast MRA compared with conventional MRA, and the two techniques do not differ substantially in the grading of arterial stenosis, despite the markedly reduced acquisition time of fast MRA. (orig.)

  3. Optimum CT reconstruction parameters for vascular and hepatocellular carcinoma models in a liver phantom with multi-level dynamic computed tomography with 64 detector rows: a basic study.

    Science.gov (United States)

    Murotani, Kazuhiro; Kazuhiro, Murotani; Kawai, Nobuyuki; Sato, Morio; Minamiguchi, Hiroki; Nakai, Motoki; Sonomura, Tetsuo; Hosokawa, Seiki; Nishioku, Tadayoshi

    2013-07-01

    We quantified to clarify the optimum factors for CT image reconstruction of an enhanced hepatocellular carcinoma (HCC) model in a liver phantom obtained by multi-level dynamic computed tomography (M-LDCT) with 64 detector rows. After M-LDCT scanning of a water phantom and an enhanced HCC model, we compared the standard deviation (SD, 1 ± SD), noise power spectrum (NPS) values, contrast-noise ratios (CNR), and the M-LDCT image among the reconstruction parameters, including the convolution kernel (FC11, FC13, and FC15), post-processing quantum filters (2D-Q00, 2D-Q01, and 2D-Q02) and slice thicknesses/slice intervals. The SD and NPS values were lowest with FC11 and 2D-Q02. The CNR values were highest with 2D-Q02. The M-LDCT image quality was highest with FC11 and 2D-Q02, and with slice thicknesses/slice intervals of 0.5 mm/0.5 mm and 0.5 mm/0.25 mm. The optimum factors were the FC11 convolution kernel, 2D-Q02 quantum filter, and 0.5 mm slice thickness/0.5 mm slice interval or less.

  4. In-Vitro Evaluation of Coronary Stents and 64-Detector-Row Computed Tomography Using a Newly Developed Model of Coronary Artery Stenosis

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    Schlosser, T.; Scheuermann, T.; Ulzheimer, S.; Mohrs, O.K.; Kuehling, M.; Albrecht, P.E.; Voigtlaender, T.; Barkhausen, J.; Schmermund, A. (Cardiovascular Center Bethanien (CCB), Frankfurt (DE))

    2008-02-15

    Background: Stent implantation is the predominant therapy for non-surgical myocardial revascularization in patients with coronary artery disease. However, despite substantial advances in multidetector computed tomography (MDCT) coronary imaging, a reliable detection of coronary in-stent restenosis is currently not possible. Purpose: To examine the ability of 64-detector-row CT to detect and to grade in-stent stenosis in coronary stents using a newly developed ex-vivo vessel phantom with a realistic CT density pattern, artificial stenosis, and a thorax phantom. Material and Methods: Four different stents (Liberte and Lunar ROX, Boston Scientific; Driver, Medtronic; Multi-Link Vision, Guidant) were examined. The stents were placed on a polymer tube with a diameter of 2.5, 3.0, 3.5, or 4.0 mm. Different degrees of stenosis (0%, 30%, 50%, 70-80%) were created inside the tube. For quantitative analysis, attenuation values were measured in the non-stenotic vessel outside the stent, in the non-stenotic vessel inside the stent, and in the stenotic area inside the stent. The grade of stenosis was visually assessed by two observers. Results: All stents led to artificial reduction of attenuation, the least degree of which was found in the Liberte stent (11.3+-10.2 HU) and the Multi-Link Vision stent (17.6+-17.9 HU; P 0.25). Overall, the non-stenotic vessel was correctly diagnosed in 55.5%, the low-grade stenosis in 58.3%, the intermediate stenosis in 63.8%, and the high-grade stenosis in 80.5%. In the 3.0-, 3.5-, and 4.0-mm vessels, in none of the cases was a non-stenotic or low-grade stenotic vessel misdiagnosed as intermediate or high-grade stenosis. The average deviation from the real grade of stenosis was 0.40 for the Liberte stent, 0.46 for the Lunar ROX stent, 0.45 for the Driver stent, and 0.58 for the Multi-Link Vision stent. Conclusion: Our ex-vivo data show that non-stenotic stents and low-grade in-stent stenosis can be reliably differentiated from intermediate and

  5. Dose reduction and image quality assessment in 64-detector row computed tomography of the coronary arteries using an automatic exposure control system.

    Science.gov (United States)

    Francone, Marco; Di Castro, Elisabetta; Napoli, Alessandro; Bolzan, Chiara; Carbone, Iacopo; Bertoletti, Linda; Iuliano, Luigi; Catalano, Carlo; Passariello, Roberto

    2008-01-01

    To evaluate dose reduction and image quality in coronary 64-slice multidetector computed tomography using an automatic exposure control system (AECs). A total of 101 patients were divided into 4 groups. Tube current was 600 and 800 mAs in groups A and B and adapted at 600 and 800 quality-reference mAs using an AECs in groups C and D. Effective dose and organ-equivalent dose were evaluated. Image noise was quantified as standard deviation of air-space attenuation. Two observers assessed technical adequacy and image quality using a 4-point scale. Effective dose ranged from 8.6 mSv (group C) to 15 mSv (group B) with significant dose reduction for examinations performed at 600 mAs (21.7%) and 800 mAs (29.4%). Contribution of organ-equivalent doses showed higher exposure for lungs (42%) and breast (22%). Noise was significantly higher in groups studied with AECs. Larger coronary segments resulted in higher image quality scores without differences between groups. Automatic exposure control systems provides images of diagnostic quality with substantial dose reduction.

  6. Comparison of the aortic valve calcium content in the bicuspid and tricuspid stenotic aortic valve using non-enhanced 64-detector-row-computed tomography with prospective ECG-triggering

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    Ferda, Jiri [Department of Radiology, Charles University Hospital Plzen, Alej Svobody 80, CZ-306 40 Plzen (Czech Republic)], E-mail: ferda@fnplzen.cz; Linhartova, Katerina [Department of Cardiology, Cardiovascular Center, Charles University Hospital Motol, V Uvalu 84, Prague (Czech Republic); Kreuzberg, Boris [Department of Radiology, Charles University Hospital Plzen, Alej Svobody 80, CZ-306 40 Plzen (Czech Republic)

    2008-12-15

    Purpose: The aim of our study was to compare the calcium content measured by non-enhanced multidetector-row-computed tomography (MDCT) between patients with significant stenosis of bicuspid (BAV) and tricuspid aortic valve (TAV). Another aim of our study was to assess the accuracy of the non-enhanced MDCT to distinguish BAV and TAV based on the calcified plaque morphology, and to compare the results with the transesophageal echocardiography. Subjects and methods: A retrospective analysis of prospectively collected data was performed. Consecutive patients with symptomatic aortic stenosis (AS) admitted to hospital for evaluation before valve surgery underwent clinical evaluation, transthoracic and transesophageal echocardiography, and non-enhanced examination with the 64-detector-row CT using prospective ECG triggering with data acquisition in diastolic phase. The data acquisition started at 55% of the R-R interval. The patients were examined in the supine position in mild inspiration. Data were evaluated using dedicated software for calcium scoring, the volume of calcifications and calcium content were obtained. Results: Thirty-seven patients (20 males, age 48-83 years) were enrolled. BAV was present in 13 patients, TAV in 24 patients. The calcium score in patients with severe AS (mean gradient >50 mmHg) was higher than in those with moderate AS (1123 {+-} 616 mg versus 634 {+-} 475, P = 0.011). Significant correlation between the calcium scores and transaortic gradients was found (r = 0.53, P = 0.002). The patients with BAV did not differ significantly from those with TAV in the AS severity (58 {+-} 13 versus 53 {+-} 20 mmHg), nor in the valve calcium score (1168 {+-} 717 versus 795 {+-} 530 mg, P = 0.093). The overall sensitivity to detect BAV in patients with calcified severe AS was 0.923 (12/13) and specificity 0.958 (23/24). The overall accuracy was 0.945 (35/37). Conclusion: We observed higher calcium score in patients with severe AS than with moderate AS

  7. Whole tumour perfusion of peripheral lung carcinoma: evaluation with first-pass CT perfusion imaging at 64-detector row CT

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    Li, Y. [Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan (China); Yang, Z.-G. [Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan (China); National Key Laboratory of Biotherapy Center, West China Hospital, Sichuan University, Chengdu, Sichuan (China)], E-mail: yangzg1117@yahoo.com.cn; Chen, T.-w.; Deng, Y.-p.; Yu, J.-q.; Li, Z.-l. [Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan (China)

    2008-06-15

    Aim: To prospectively assess the feasibility of a whole-tumour perfusion technique using 64-detector row computed tomography (CT) and to analyse the variation of CT perfusion parameters in different histological types, sizes, and metastases in patients with peripheral lung carcinoma. Methods and materials: Ninety-seven pathologically proved peripheral lung carcinomas (less than 5 cm in largest diameter) underwent dynamic contrast-enhanced CT using a 64-detector row CT machine. Small amounts of iodinated contrast medium with a sharp bolus profile (50 ml, 6-7 ml/s), and 12 repeated fast acquisitions encompassing the entire tumour lesion were adopted to quantify perfusion of the whole-tumour during first-pass of contrast medium. Four kinetic parameters, including perfusion, peak enhancement intensity (PEI), time to peak (TTP), and blood volume (BV), were measured and statistically compared among different histological types, sizes, and metastases. Results: Mean values for perfusion, PEI, TTP, and BV of the 97 lung carcinomas were 57.5 {+-} 45.4 ml/min/ml (range 5.9-243 ml/min/ml), 53.4 {+-} 40.6 HU (range 10.3-234.4 HU), 34 {+-} 11 s (range 11-60 s), and 30.1 {+-} 21.7 ml/100 g (range 3.9-113.4 ml/100 g), respectively. No statistical differences were found between the histological types regarding the perfusion parameters (p > 0.05). Perfusion, PEI, and BV of stage T2 tumours were significantly lower than those of stage T1 tumours (all p < 0.05), whereas no statistically significant differences was found between other stages of tumours (all p > 0.05). Perfusion of the tumours with distant metastasis was significantly higher than that of the tumours without distant metastasis (p < 0.05), but there was no statistically significant difference between nodal metastasis positive and negative groups (p > 0.05). Conclusion: The present study of first-pass perfusion imaging using 64-detector row CT could provide a feasible method for assessment of whole-tumour perfusion. CT

  8. Does Gadoxetic acid-enhanced 3.0T MRI in addition to 64-detector-row contrast-enhanced CT provide better diagnostic performance and change the therapeutic strategy for the preoperative evaluation of colorectal liver metastases?

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    Sofue, Keitaro [National Cancer Center Hospital, Division of Diagnostic Radiology, Tokyo (Japan); Kobe University, Department of Radiology, Graduate School of Medicine, Kobe (Japan); Tsurusaki, Masakatsu [National Cancer Center Hospital, Division of Diagnostic Radiology, Tokyo (Japan); Kinki University, Department of Radiology, Faculty of Medicine, Osakasayama, Osaka (Japan); Murakami, Takamichi [Kinki University, Department of Radiology, Faculty of Medicine, Osakasayama, Osaka (Japan); Onoe, Shunsuke [National Cancer Center Hospital, Department of Hepatobiliary and Pancreatic Surgery, Tokyo (Japan); Tokue, Hiroyuki; Shibamoto, Kentaro; Arai, Yasuaki [National Cancer Center Hospital, Division of Diagnostic Radiology, Tokyo (Japan); Sugimura, Kazuro [Kobe University, Department of Radiology, Graduate School of Medicine, Kobe (Japan)

    2014-10-15

    To compare diagnostic performance in the detection of colorectal liver metastases between 64-detector-row contrast-enhanced CT (CE-CT) alone and the combination of CE-CT and gadoxetic acid-enhanced MRI (EOB-MRI) at 3.0T, and to assess whether EOB-MRI in addition to CE-CT results in a change to initially planned operative strategy. A total of 39 patients (27 men, mean age 65 years) with 85 histopathologically confirmed liver metastases were included. At EOB-MRI, unenhanced (T1- and T2-weighted), dynamic, and hepatocyte-phase images were obtained. At CE-CT, four-phase dynamic contrast-enhanced images were obtained. One on-site reader and three off-site readers independently reviewed both CE-CT alone and the combination of CE-CT and EOB-MRI. Sensitivity, positive predictive value, and alternative free-response receiver operating characteristic (AFROC) method were calculated. Differences in therapeutic strategy before and after the EOB-MRI examination were also evaluated. Sensitivity and area under the AFROC curve with the combination of CE-CT and EOB-MRI were significantly superior to those with CE-CT alone. Changes in surgical therapy were documented in 13 of 39 patients. The combination of CE-CT and EOB-MRI may provide better diagnostic performance than CE-CT alone for the detection of colorectal liver metastases, and EOB-MRI in addition to CE-CT resulted in changes to the planned operative strategy in one-third of the patients. (orig.)

  9. Computed Tomography (CT) -- Head

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    Full Text Available ... Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special ... the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a CT ...

  10. Ultra-High-Resolution Computed Tomography of the Lung: Image Quality of a Prototype Scanner.

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    Ryutaro Kakinuma

    Full Text Available The image noise and image quality of a prototype ultra-high-resolution computed tomography (U-HRCT scanner was evaluated and compared with those of conventional high-resolution CT (C-HRCT scanners.This study was approved by the institutional review board. A U-HRCT scanner prototype with 0.25 mm x 4 rows and operating at 120 mAs was used. The C-HRCT images were obtained using a 0.5 mm x 16 or 0.5 mm x 64 detector-row CT scanner operating at 150 mAs. Images from both scanners were reconstructed at 0.1-mm intervals; the slice thickness was 0.25 mm for the U-HRCT scanner and 0.5 mm for the C-HRCT scanners. For both scanners, the display field of view was 80 mm. The image noise of each scanner was evaluated using a phantom. U-HRCT and C-HRCT images of 53 images selected from 37 lung nodules were then observed and graded using a 5-point score by 10 board-certified thoracic radiologists. The images were presented to the observers randomly and in a blinded manner.The image noise for U-HRCT (100.87 ± 0.51 Hounsfield units [HU] was greater than that for C-HRCT (40.41 ± 0.52 HU; P < .0001. The image quality of U-HRCT was graded as superior to that of C-HRCT (P < .0001 for all of the following parameters that were examined: margins of subsolid and solid nodules, edges of solid components and pulmonary vessels in subsolid nodules, air bronchograms, pleural indentations, margins of pulmonary vessels, edges of bronchi, and interlobar fissures.Despite a larger image noise, the prototype U-HRCT scanner had a significantly better image quality than the C-HRCT scanners.

  11. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT of the sinuses is primarily used ...

  12. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... the limitations of CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, ... the body being studied. top of page How is the procedure performed? The technologist begins by positioning ...

  13. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT of the sinuses is primarily used ...

  14. Value of Multidetector Computed Tomography in Evaluation of Thoracic Venous Abnormalities among Pediatrics with Congenital Heart Disease

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    Dalia F Elbeih*, Mervat M El-Gohary *, Naglaa H Shebrya*,Mohammed A Saleh

    2013-04-01

    Full Text Available Introduction: Venous anomalies of the thorax can involve systemic or pulmonary veins and range from isolated incidental findings to components of more complex anomalies, most often congenital heart disease (CHD. Although echocardiography and catheter directed cardiac angiography are generally accepted as the primary imaging techniques for evaluation of CHD, CT and MRI are important complementary diagnostic tools. Multi-detector computed tomography (MDCT with its increasing availability and utility is now becoming a further method of imaging CHD. In light of its widespread availability, MDCT and 3D imaging are increasingly considered as a viable “one-stop shop” for preoperative imaging evaluation of cardiovascular structures in selected pediatric patients.Aim of the work: The aim of this work is to evaluate the role of MDCT in visualization of the thoracic venous system in pediatrics with congenital heart disease, show prevalence and types of venous anomalies and to compare this data with echocardiographic findings.Methods: The studied group included 30 cases referred to us by pediatric cardiologists to be examined by MSCT angiography of the heart and thoracic vessels. All the patients were known cases of congenital heart disease and underwent echocardiography. They were referred to answer specific anatomic question raised by inconclusive echocardiography, to assess suspected systemic and suspected pulmonary venous anomalies. All patients were subjected to full history taking, clinical examination and MDCT examination with CT lightspeed VCT XT 64-detectors row scanner (General Electric, Medical Systems, Milwaukee, Wisconsin, USA.Results: CTA findings had 77.8 % concordance with echocardiographic findings regarding SVC anomalies, 66.7 % concordance with echocardiography regarding IVC anomalies and 90 % concordance regarding pulmonary venous anomalies.Conclusion: Low dose protocol CTA is a promising method that complementary to Echocardioraphy

  15. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) ... are the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known as a ...

  16. Computed Tomography (CT) -- Head

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    Full Text Available ... of the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT scanning of the head is typically ...

  17. Computed Tomography (CT) -- Head

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    Full Text Available ... limitations of CT Scanning of the Head? What is CT Scanning of the Head? Computed tomography, more ... the body being studied. top of page How is the procedure performed? The technologist begins by positioning ...

  18. Computed Tomography (CT) -- Head

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  19. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  20. Computed Tomography (CT) -- Head

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    Full Text Available ... CT scanner technique will be adjusted to their size and the area of interest to reduce the ... Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and ...

  1. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... CT scanner technique will be adjusted to their size and the area of interest to reduce the ... Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and ...

  2. Computed Tomography (CT) -- Head

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    Full Text Available ... of the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT scanning of the head is typically ...

  3. Computed Tomography (CT) -- Head

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    Full Text Available ... Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography ( ... stroke and brain tumors. It also helps your doctor to evaluate your face, sinuses, and skull or ...

  4. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography ( ... the best imaging modality for sinusitis. Tell your doctor if there’s a possibility you are pregnant and ...

  5. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  6. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... for a recovery period and will be given instructions on any limitations in activity for the day. ... Images related to Children's (Pediatric) CT (Computed Tomography) Videos related to Children's (Pediatric) CT (Computed Tomography) Sponsored ...

  7. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Computed Tomography) Pediatric computed tomography (CT) is a fast, painless exam that uses special x-ray equipment ... period of time. Modern CT scanners are so fast that they can scan through large sections of ...

  8. Children's (Pediatric) CT (Computed Tomography)

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    ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Us News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography ( ... more commonly known as a CT or CAT scan, is a diagnostic medical test that, like traditional ...

  10. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Computed Tomography) Pediatric computed tomography (CT) is a fast, painless exam that uses special x-ray equipment ... period of time. Modern CT scanners are so fast that they can scan through large sections of ...

  11. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is a fast, painless ... table. Other imaging methods such as ultrasound or magnetic resonance (MR) imaging can provide pictures of certain areas ...

  12. Proton computed tomography

    Science.gov (United States)

    Bucciantonio, Martina; Sauli, Fabio

    2015-05-01

    Proton computed tomography (pCT) is a diagnostic method capable of in situ imaging the three-dimensional density distribution in a patient before irradiation with charged particle beams. Proposed long time ago, this technology has been developed by several groups, and may become an essential tool for advanced quality assessment in hadrontherapy. We describe the basic principles of the method, its performance and limitations as well as provide a summary of experimental systems and of results achieved.

  13. Computer processing of tomography data

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    Konečný, Jan

    2011-01-01

    Computer processing of tomography data Tomographs are one of the most important diagnostic devices, which are used in every hospital nowadays; they have already been so for a considerable period of time. The different types of tomographs and the processing of tomographic data and imaging of these data are the subject of this thesis. I have described the four most common types of tomography: X-ray Computed Tomography, Magnetic Resonance Imaging, Positron Emission Tomography and Single Photon E...

  14. Multiplanner spine computed tomography

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    Chung, H. K.; Jeon, H. J.; Hong, K. C.; Chung, K. B.; Suh, W. H. [Korea University College of Medicine, Seoul (Korea, Republic of)

    1983-06-15

    The computed tomography is useful in evaluation of bony structures and adjacent soft tissues of the spine. Recently, the multiplanar spine CT scan is highly superior than usual axial scan, because of easily demonstrable longitudinal dimension, level of spine and spinal canal. We evaluated 62 cases of spine CT, whom complains of spinal symptoms, from July, 1982 to January, 1983. The results were as follows: 1. The sex distribution of cases were 45 male and 17 female, ages were from 15 years to 76 years, and sites were 15 cervical spine, 7 thoracic spine, 42 lumbar spine and 21 sacral spine. 2. Sixty two cases of the CT diagnosis were reviewed and shows 19 cases of herniated intervertebral disc, 7 cases of spine fracture, 5 cases of degenerative disease, 4 cases of metastatic cancer, 2 cases of posterior longitudinal ligament ossification, 1 case of cord injury and 24 cases of normal. 3. The CT findings of herniated intervertebral disc were protruding disc, obliteration of anterior epidural fat, with or without indentation of dural sac and calcification within posterior disc margin. In cases of trauma, the multiplanar spine CT scan detects more specific extension of the fracture sites, and it is able to demonstrate relationship between fracture fragment and spinal cord, therefore operability can be decided. In case of posterior longitudinal ligament ossification, it is easy to demonstrate linear high density along posterior margin of vertebral bodies on sagittal reconstruction scan. 4. The computed tomography is diagnostic in detection of spinal disease. However, multiplanar spine CT is more diagnostic than axial computed tomography such as detecting the longitudinal dimension and demonstration of spinal canal.

  15. Abdominal perfusion computed tomography.

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    Ogul, Hayri; Bayraktutan, Ummugulsum; Kizrak, Yesim; Pirimoglu, Berhan; Yuceler, Zeynep; Sagsoz, M Erdem; Yilmaz, Omer; Aydinli, Bulent; Ozturk, Gurkan; Kantarci, Mecit

    2013-02-01

    The purpose of this article is to provide an up to date review on the spectrum of applications of perfusion computed tomography (CT) in the abdomen. New imaging techniques have been developed with the objective of obtaining a structural and functional analysis of different organs. Recently, perfusion CT has aroused the interest of many researchers who are studying the applicability of imaging modalities in the evaluation of abdominal organs and diseases. Per-fusion CT enables fast, non-invasive imaging of the tumor vascular physiology. Moreover, it can act as an in vivo biomarker of tumor-related angiogenesis.

  16. Chest computed tomography

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    Loeve, Martine; Krestin, Gabriel P.; Rosenfeld, Margaret

    2013-01-01

    Clinical trials for the treatment of cystic fibrosis (CF) lung disease are important to test and optimize new therapeutic interventions. To evaluate the effect of these interventions, sensitive and accurate outcome measures are needed. The most commonly used endpoints are spirometric variables...... are not suitable to study CF lung disease in young children. Chest computed tomography (CT) holds great promise for use as a sensitive surrogate endpoint in CF. A large body of evidence has been produced to validate the use of chest CT as primary endpoint to study CF lung disease. However, before chest CT can...

  17. Stored Luminescence Computed Tomography

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    Cong, Wenxiang; Wang, Ge

    2013-01-01

    The phosphor nanoparticles made of doped semiconductors, pre-excited by well-collimated X-ray radiation, were recently reported for their light emission upon NIR light stimulation. The characteristics of X-ray energy storage and NIR stimulated emission is highly desirable to design targeting probes and improve molecular and cellular imaging. Here we propose stored luminescence computed tomography (SLCT), perform realistic numerical simulation, and demonstrate a much-improved spatial resolution in a preclinical research context. The future opportunities are also discussed along this direction.

  18. Metrizamide computed tomography in syringomyelia

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    Ogawa, T.; Tamakawa, Y.; Arii, H. (Akita Univ. (Japan). Faculty of Medicine); Takahashi, M.; Hirota, K.

    1981-11-01

    Serial computed tomography of the cervical cord was performed following metrizamide myelography in five cases of clinically suspected syringomyelia. The syrinx filled with refluxed metrizamide was demonstrated in all of the cases. The reflux of metrizamide into the syrinx was most marked several hours following intrathecal injection of metrizamide. Computed tomography combined with metrizamide myelography is essential in the diagnosis of communicating syringomyelia.

  19. [Computed tomography of the heart

    DEFF Research Database (Denmark)

    Kristensen, T.S.; Kofoed, K.F.; der, Recke P. von;

    2009-01-01

    Noninvasive evaluation of the coronary arteries by multi-detector row computed tomography is a promising new alternative to conventional invasive coronary angiography. This article describes the technical background, methods, limitations and clinical applications and reviews current literature...

  20. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... What are the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known as ... the body being studied. top of page How is the procedure performed? The technologist begins by positioning ...

  1. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  2. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  3. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... tomography, more commonly known as a CT or CAT scan, is a diagnostic medical test that, like ... contrast materials and a metallic taste in your mouth that lasts for at most a minute or ...

  4. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... tomography, more commonly known as a CT or CAT scan, is a diagnostic medical test that, like ... contrast materials and a metallic taste in your mouth that lasts for at most a minute or ...

  5. Computed tomography of the prostate.

    Science.gov (United States)

    Van Engelshoven, J M; Kreel, L

    1979-02-01

    The conventional anatomy of the prostate is reviewed and the computed tomography (CT) anatomy described and illustrated. The results of 55 "normal" cases were analyzed for size and relationship to the symphysis pubis, retropubic space, and bladder, as shown on CT sections correlating the features with age and possible urinary symptoms. Attention is also drawn to the differences between phleboliths and prostatic calcification. Computed tomography is an effective method of demonstrating the prostate and surrounding structures and of assessing prostatic enlargement.

  6. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  7. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  8. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  9. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  10. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  11. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  12. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ...

  13. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ...

  14. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of ... Society of Urogenital Radiology note that the available data suggest that it is safe to continue breastfeeding ...

  15. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of ... Society of Urogenital Radiology note that the available data suggest that it is safe to continue breastfeeding ...

  16. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... images can be viewed on a computer monitor, printed on film or transferred to a CD or ... Rotating around you, the x-ray tube and electronic x-ray detectors are located opposite each other ...

  17. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... images can be viewed on a computer monitor, printed on film or transferred to a CD or ... Rotating around you, the x-ray tube and electronic x-ray detectors are located opposite each other ...

  18. Computed tomography:the details.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2007-07-01

    Computed Tomography (CT) is a well established technique, particularly in medical imaging, but also applied in Synthetic Aperture Radar (SAR) imaging. Basic CT imaging via back-projection is treated in many texts, but often with insufficient detail to appreciate subtleties such as the role of non-uniform sampling densities. Herein are given some details often neglected in many texts.

  19. Viewing Welds By Computer Tomography

    Science.gov (United States)

    Pascua, Antonio G.; Roy, Jagatjit

    1990-01-01

    Computer tomography system used to inspect welds for root penetration. Source illuminates rotating welded part with fan-shaped beam of x rays or gamma rays. Detectors in circular array on opposite side of part intercept beam and convert it into electrical signals. Computer processes signals into image of cross section of weld. Image displayed on video monitor. System offers only nondestructive way to check penetration from outside when inner surfaces inaccessible.

  20. Cranial computed tomography in pediatrics

    Energy Technology Data Exchange (ETDEWEB)

    Boltshauser, E. (Zuerich Univ. (Switzerland). Kinderklinik)

    1984-01-01

    This paper deals mainly with methodical aspects (such as sedation, intravenous and intrathecal application of contrast media) and with common difficulties in interpretation of computed tomography images. The indications for cranial CT are discussed in respect to probable therapeutic consequences and expected diagnostic yield. In the view of the author CT is, as a rule, not required in assessing chronic headache, generalised epileptic convulsions, non-specific mental retardation and cerebral palsy.

  1. Industrial applications of computed tomography

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Carmignato, S.; Kruth, J. -P.

    2014-01-01

    The number of industrial applications of Computed Tomography(CT) is large and rapidly increasing. After a brief market overview, the paper gives a survey of state of the art and upcoming CT technologies, covering types of CT systems, scanning capabilities, and technological advances. The paper...... contains a survey of application examples from the manufacturing industry as well as from other industries, e.g., electrical and electronic devices, inhomogeneous materials, and from the food industry. Challenges as well as major national and international coordinated activities in the field of industrial...

  2. Computed Tomography in Forensic Medicine

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    2015-01-01

    Modern diagnostic imagining techniques are gaining popularity in forensic medicine. Denmark has been involved in the development of this use of imaging techniques from the beginning. The Institute of Forensic Medicine at the University of Southern Denmark acquired a helical computed tomography (CT...... AND METHODS: This thesis investigated 900 forensic cases that were CT-scanned and autopsied at the Institute of Forensic Medicine, University of Southern Denmark, from 2006-2011. The scanner was a Siemens Somatom Spirit dual-slice CT-scanner with a Siemens Syngo MultiModality workstation. Contrast enhancement...

  3. Future of cardiac computed tomography

    Institute of Scientific and Technical Information of China (English)

    Carlo N De Cecco; U Joseph Schoepf

    2015-01-01

    Coronary computed tomography angiography(CCTA)has become an integral tool in the noninvasive diagnostic workup of patients with suspected coronary artery disease in both elective and emergency settings. Today, it represents a mature technique providing accurate, non-invasive morphological assessment of the coronary arteries and atherosclerotic plaque burden. Iterative reconstruction algorithms, low kV imaging, and single-heart beat acquisitions hold promise to further reduce dose requirements and improve the safety and robustness of the technique in several circumstances including imaging of heavily calcified vessels, patients with morbid obesity or irregular heart rates, and assessment in the emergency setting. However, it has become clear over recent years that cardiac radiologists need to take further steps towards the development and integration of functional imaging with morphological CCTA assessment to truly provide a comprehensive evaluation of the heart. Computed tomography myocardial perfusion imaging, including both dynamic and static dual-energy approaches, has demonstrated the ability to directly assess and quantify myocardial ischemia with simultaneous CCTA acquisition with a reasonable contrast medium volume and radiation dose delivered to the patient. In order to promote CCTA in the clinical and research environments, radiologists should prepare to embrace the change from morphological to functional imaging, furnishing all the necessary resources and information to referring clinicians.

  4. Adaptive Computed Tomography Imaging Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The present proposal describes the development of an adaptive Computed Tomography Imaging Spectrometer (CTIS), or "Snapshot" spectrometer which can "instantaneously"...

  5. Computed tomography of the gallbladder.

    Science.gov (United States)

    Havrilla, T R; Reich, N E; Haaga, J R; Seidelmann, F E; Cooperman, A M; Alfidi, R J

    1978-06-01

    Computed tomography (CT) was used to study 79 patients with suspected gallbladder disease. First and second generation scanners were used to determine the efficacy of CT in detecting cholecystitis or cholelithiasis. Manifestations of gallbladder disease such as hydrops, opaque and nonopaque gallstones, chronic cholecystitis with thickened inflammatory walls, and secondary liver abscesses can be easily detected. It is a useful technique for individuals in whom the gallbladder has failed to opacity on oral cholecystography. The scanning method is described, and estimates of reliability are given including its accuracy, limitations, and place in the management of gallbladder disease, especially cholelithiasis. When conventional radiographic examinations or ultrasound fail to give definitive diagnostic information, CT can be a useful alternative with an overall diagnostic accuracy greater than 80%.

  6. [Computer tomography of sports injuries].

    Science.gov (United States)

    Reiser, M; Rupp, N

    1984-01-01

    Computed tomography (CT) provides axial slices plane and shows excellent details of bones and different soft tissues, favoring its use in traumatic lesions caused by sporting activities. Complex anatomical structures such as the shoulder, the vertebral column, the pelvis, the knee, the tarsal and carpal bones are often better recognized in detail than by conventional radiography. Fracture lines, localization of bone fragments and involvement of soft tissues are clearly demonstrated. Luxations and bone changes leading to luxations can be shown. CT arthrography provides for the first time a direct visualization of joint cartilage and of cruciate ligaments in the knee joint, so traumatic lesions such as chondropathia patellae or rupture of the cruciate ligaments are shown with a high degree of reliability.

  7. Computed tomography in sport injuries

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, M.; Rupp, N.

    1984-01-01

    Computed tomography (CT) provides axial slices plane and shows excellent details of bones and different soft tissues, favoring its use in traumatic lesions caused by sporting activities. Complex anatomical structures such as the shoulder, the vertebral column, the pelvis, the knee, the tarsal and carpal bones are often better recognized in detail than by conventional radiography. Fracture lines, localization of bone fragments and involvement of soft tissues are clearly demonstrated. Luxations and bone changes leading to luxations can be shown. CT arthrography provides for the first time a direct visualization of joint cartilage and of cruciate ligaments in the knee joint, so traumatic lesions such as chondropathia patellae or rupture of the cruciate ligaments are shown with a high degree of reliability.

  8. Computed tomography of cryogenic cells

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Gerd; Anderson, E.; Vogt, S.; Knochel, C.; Weiss, D.; LeGros, M.; Larabell, C.

    2001-08-30

    Due to the short wavelengths of X-rays and low numerical aperture of the Fresnel zone plates used as X-ray objectives, the depth of field is several microns. Within the focal depth, imaging a thick specimen is to a good approximation equivalent to projecting the specimen absorption. Therefore, computed tomography based on a tilt series of X-ray microscopic images can be used to reconstruct the local linear absorption coefficient and image the three-dimensional specimen structure. To preserve the structural integrity of biological objects during image acquisition, microscopy is performed at cryogenic temperatures. Tomography based on X-ray microscopic images was applied to study the distribution of male specific lethal 1 (MSL-1), a nuclear protein involved in dosage compensation in Drosophila melanogaster, which ensures that males with single X chromosome have the same amount of most X-linked gene products as females with two X chromosomes. Tomographic reconstructions of X-ray microscopic images were used to compute the local three-dimensional linear absorption coefficient revealing the arrangement of internal structures of Drosophila melanogaster cells. Combined with labelling techniques, nanotomography is a new technique to study the 3D distribution of selected proteins inside whole cells. We want to improve this technique with respect to resolution and specimen preparation. The resolution in the reconstruction can be significantly improved by reducing the angular step size to collect more viewing angles, which requires an automated data acquisition. In addition, fast-freezing with liquid ethane instead of cryogenic He gas will be applied to improve the vitrification of the hydrated samples. We also plan to apply cryo X-ray nanotomography in order to study different types of cells and their nuclear protein distributions.

  9. Cardiac Computed Tomography (Multidetector CT, or MDCT)

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Cardiac Computed Tomography (Multidetector CT, or MDCT) Updated:Sep 19, ... The ECG is also needed to help the computer that is connected to the CT scanner create ...

  10. RADIATION DOSE IN PAEDIATRIC COMPUTED TOMOGRAPHY ...

    African Journals Online (AJOL)

    Computed tomography (CT) is a powerful tool for the accurate ... increasing, and estimates suggest that quantitative lifetime ... Keywords: Computed Tomography, Radiation Risk, Radiation Dose, Patient Dose ... techniques, such as MRI and ultrasound, which do not ..... in the course of management are not monitored to.

  11. [Computed tomography and cranial paleoanthropology].

    Science.gov (United States)

    Cabanis, Emmanuel Alain; Badawi-Fayad, Jackie; Iba-Zizen, Marie-Thérèse; Istoc, Adrian; de Lumley, Henry; de Lumley, Marie-Antoinette; Coppens, Yves

    2007-06-01

    Since its invention in 1972, computed tomography (C.T.) has significantly evolved. With the advent of multi-slice detectors (500 times more sensitive than conventional radiography) and high-powered computer programs, medical applications have also improved. CT is now contributing to paleoanthropological research. Its non-destructive nature is the biggest advantage for studying fossil skulls. The second advantage is the possibility of image analysis, storage, and transmission. Potential disadvantages include the possible loss of files and the need to keep up with rapid technological advances. Our experience since the late 1970s, and a recent PhD thesis, led us to describe routine applications of this method. The main contributions of CT to cranial paleoanthropology are five-fold: --Numerical anatomy with rapid acquisition and high spatial resolution (helicoidal and multidetector CT) offering digital storage and stereolithography (3D printing). --Numerical biometry (2D and 3D) can be used to create "normograms" such as the 3D craniofacial reference model used in maxillofacial surgery. --Numerical analysis offers thorough characterization of the specimen and its state of conservation and/or restoration. --From "surrealism" to virtual imaging, anatomical structures can be reconstructed, providing access to hidden or dangerous zones. --The time dimension (4D imaging) confers movement and the possibility for endoscopic simulation and internal navigation (see Iconography). New technical developments will focus on data processing and networking. It remains our duty to deal respectfully with human fossils.

  12. X-ray computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kalender, Willi A [Institute of Medical Physics, University Erlangen-Nuernberg, Henkestr. 91, D-91052 Erlangen (Germany)

    2006-07-07

    X-ray computed tomography (CT), introduced into clinical practice in 1972, was the first of the modern slice-imaging modalities. To reconstruct images mathematically from measured data and to display and to archive them in digital form was a novelty then and is commonplace today. CT has shown a steady upward trend with respect to technology, performance and clinical use independent of predictions and expert assessments which forecast in the 1980s that it would be completely replaced by magnetic resonance imaging. CT not only survived but exhibited a true renaissance due to the introduction of spiral scanning which meant the transition from slice-by-slice imaging to true volume imaging. Complemented by the introduction of array detector technology in the 1990s, CT today allows imaging of whole organs or the whole body in 5 to 20 s with sub-millimetre isotropic resolution. This review of CT will proceed in chronological order focussing on technology, image quality and clinical applications. In its final part it will also briefly allude to novel uses of CT such as dual-source CT, C-arm flat-panel-detector CT and micro-CT. At present CT possibly exhibits a higher innovation rate than ever before. In consequence the topical and most recent developments will receive the greatest attention. (review)

  13. Computed tomography of arachnoid cyst

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Min Gi; Bae, Weon Tae; Kim, Jae Kyu; Park, Jin Gyoon; Kang, Heoung Keun; Chung, Hyun De [College of Medicine, Chonnam National University, Kwangju (Korea, Republic of)

    1988-02-15

    The preoperative diagnosis of intracranial arachnoid cysts has been simplified, and made more rapid and accurate with computed tomography (CT). Using CT cisternography, detailed anatomic and physiologic information of arachnoid cysts could be obtained. CT features of pathologically proven 21 arachnoid cysts that were examined at Chonnam National University Hospital from June 1983 to May 1987 were analyzed. The results were as follows: 1.Prevalent age group was the 1st decade (8 cases) and male to female ratio was 17:4. 2.Clinical features were related to the location of arachnoid cyst, common symptoms were headache (53.3%), convulsion, mental change and walking disturbance. 3.Location of the arachnoid cyst were in supratentorial region (15 cases) most in middle cranial fossa (12 cases), and infratentorial region (6 cases), common at the retrocerebellar cisternal space (3 cases). 4.Shapes of arachnoid cyst were biconvex with straight inner margin (8 cases), spherical (7 cases), simple biconvex (3 cases) and others (3 cases). 5.Size of the arachnoid cyst, in the greatest dimension, was ranged from 2cm to 9cm and commonly distributed between 3cm to 5cm (14 cases). 6.Of all 14 cases, who did CT cisternography using metrizamide (11 cases) and iopamidol (3 cases), 2 cases had communication with the subarachnoid space.

  14. A Freeware Path to Neutron Computed Tomography

    Science.gov (United States)

    Schillinger, Burkhard; Craft, Aaron E.

    Neutron computed tomography has become a routine method at many neutron sources due to the availability of digital detection systems, powerful computers and advanced software. The commercial packages Octopus by Inside Matters and VGStudio by Volume Graphics have been established as a quasi-standard for high-end computed tomography. However, these packages require a stiff investment and are available to the users only on-site at the imaging facility to do their data processing. There is a demand from users to have image processing software at home to do further data processing; in addition, neutron computed tomography is now being introduced even at smaller and older reactors. Operators need to show a first working tomography setup before they can obtain a budget to build an advanced tomography system. Several packages are available on the web for free; however, these have been developed for X-rays or synchrotron radiation and are not immediately useable for neutron computed tomography. Three reconstruction packages and three 3D-viewers have been identified and used even for Gigabyte datasets. This paper is not a scientific publication in the classic sense, but is intended as a review to provide searchable help to make the described packages usable for the tomography community. It presents the necessary additional preprocessing in ImageJ, some workarounds for bugs in the software, and undocumented or badly documented parameters that need to be adapted for neutron computed tomography. The result is a slightly complicated, but surprisingly high-quality path to neutron computed tomography images in 3D, but not a replacement for the even more powerful commercial software mentioned above.

  15. Orbital computed tomography for exophthalmos

    Energy Technology Data Exchange (ETDEWEB)

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

    1987-06-15

    Since exophthalmos is caused by any decrease in the size of bony orbit or occurrence of mass within the rigid orbit, the accurate diagnosis of its causes are essential in determining the therapeutic aims. Exophthalmos is one of the important signs being the indication for orbital computed tomography along with periorbital swelling, visual loss, orbital trauma and diplopia. CT as the diagnostic tool for the cause of exophthalmos not only displays a superb role with uncomparable quality in comparison to any conventional diagnostic methods but also has a decisive role in determining the therapeutic aims and the appropriate operative method when the operation is indicated. The orbital CT was performed from May in 1983 to May in 1985 whose with chief complaints were exophthalmos and 23 cases were confirmed by operation, biopsy, clinical progression or other diagnostic procedures. Here was report thoroughly analyzed 23 cases. The results were as follows : 1. The etiologic disease of exophthalmos were 6 cases of pseudotumor, 4 cases of thyroid ophthalmopathy, 4 cases of maxill ary sinus and nasal cavity Ca., 3 cases of mucocele and 1 case of alveolar soft part sarcoma, osteoma, dermoid cyst, pleomorphic adenoma, meningioma, and C.C.F. each. 2. The origin of the etiologic diseases of exophthalmos were 13 cases of primary within bony orbit and 10 cases of secondary from adjacent structure. 3. The site of lesions were 11 cases of intraconal and extraconal, 10 cases of extraconal, and 2 cases of intraconal origin. 4. The degree of exophthalmos in CT scan was in proportion to the volume of the mass except in the case of thyroid ophthalmopathy. The upper limit of normal range by CT scan using regression line equation was 16.2 mm in approximation. 5. CT was a very useful diagnostic tool in the accurate assessment of the kinds of lesion, its location, and its relationship to adjacent structures in the diagnosis of etiologic diseases of exophthalmos.

  16. Iterative Reconstruction for Cardiopulmonary Computed Tomography

    NARCIS (Netherlands)

    Willemink, M.J.

    2015-01-01

    Introduction The number of computed tomography (CT) examinations has increased rapidly since CT became commercially available. This resulted in growing concerns regarding the risk of malignancies induced by application of medical ionizing radiation. Therefore, radiation dose reduction strategies ar

  17. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... tomography, more commonly known as a CT or CAT scan, is a diagnostic medical test that, like ... materials and a metallic taste in his/her mouth that lasts for a few minutes. Occasionally, a ...

  18. Quantitative computed tomography evaluation of pulmonary disease

    DEFF Research Database (Denmark)

    Mcevoy, Fintan J; Buelund, Lene; Strathe, Anders B

    2009-01-01

    Objective assessment of pulmonary disease from computed tomography (CT) examinations is desirable but difficult. When such assessments can be made, it is important that they are related to some part of the pathophysiologic process present.......Objective assessment of pulmonary disease from computed tomography (CT) examinations is desirable but difficult. When such assessments can be made, it is important that they are related to some part of the pathophysiologic process present....

  19. Computed tomography in abnormalities of the hip

    Energy Technology Data Exchange (ETDEWEB)

    Visser, J.D.; Jonkers, A.; Klasen, H.J. (Rijksuniversiteit Groningen (Netherlands). Academisch Ziekenhuis); Hillen, B. (Rijksuniversiteit Groningen (Netherlands). Lab. voor Anatomie en Embryologie)

    1982-06-26

    The value of computed tomography in the assessment of abnormalities of the hip is demonstrated with the aid of an anatomical preparation and in patients with, respectively, congenital dislocation of a hip, dislocation of the hip in spina bifida, an acetabular fracture and a Ewing tumour. The anteversion of the acetabulum and femur and the instability index of the hip joint can be measured by means of computed tomography.

  20. Examination of weld defects by computed tomography

    Directory of Open Access Journals (Sweden)

    M. Jovanović

    2012-04-01

    Full Text Available Defects in metal arc gas (MAG welds made in S235JR low carbon steel of 6 mm thickness were examined. A sample containing lack of fusion (LOF and pores was examined by computed tomography – CT. The computed tomography examination was performed in order to define LOF size and position as well as dimensions and distribution of accompanying pores in the weld metal.

  1. Single photon emission computed tomography/computed tomography of the skull in malignant otitis externa.

    Science.gov (United States)

    Chakraborty, Dhritiman; Bhattacharya, Anish; Kamaleshwaran, Koramadai Karuppusamy; Agrawal, Kanhaiyalal; Gupta, Ashok Kumar; Mittal, Bhagwant Rai

    2012-01-01

    Malignant otitis externa is a severe, rare infective condition of the external auditory canal and skull base. The diagnosis is generally made from a range of clinical, laboratory, and imaging findings. Technetium 99m methylene diphosphonate bone scintigraphy is known to detect osteomyelitis earlier than computed tomography. The authors present a patient with bilateral malignant otitis externa where the extent of skull base involvement was determined on 3-phase bone scintigraphy with single photon emission computed tomography/computed tomography.

  2. Computed Tomography evaluation of maxillofacial injuries

    Directory of Open Access Journals (Sweden)

    V Natraj Prasad

    2017-01-01

    Full Text Available Background & Objectives: The maxillofacial region, a complex anatomical structure, can be evaluated by conventional (plain films, Tomography, Multidetector Computed Tomography, Three-Dimensional Computed Tomography, Orthopantomogram and Magnetic Resonance Imaging. The study was conducted with objective of describing various forms of maxillofacial injuries, imaging features of different types of maxillofacial fractures and the advantage of using Three- Dimensional Computed Tomography reconstructed image. Materials & Methods: A hospital based cross-sectional study was conducted among 50 patients during April 2014 to September 2016 using Toshiba Aquilion Prime 160 slice Multi Detector Computed Tomography scanner.Results: The maxillofacial fractures were significantly higher in male population (88% than female population (12 %. Road traffic accidents were the most common cause of injury others being physical assault and fall from height. It was most common in 31-40 years (26% and 21-30 (24% years age group. Maxillary sinus was the commonest fracture (36% followed by nasal bone and zygomatic bone (30%, mandible and orbital bones (28%. Soft tissue swelling was the commonest associated finding. Three dimensional images (3 D compared to the axial scans missed some fractures. However, the extension of the complex fracture lines and degree of displacement were more accurately assessed. Complex fractures found were Le fort (6% and naso-orbito-ethmoid (4% fractures.Conclusion: The proper evaluation of complex anatomy of the facial bones requires Multidetector Computed Tomography which offers excellent spatial resolution enabling multiplanar reformations and three dimensional reconstructions for enhanced diagnostic accuracy and surgical planning.

  3. Proton computed tomography images with algebraic reconstruction

    Science.gov (United States)

    Bruzzi, M.; Civinini, C.; Scaringella, M.; Bonanno, D.; Brianzi, M.; Carpinelli, M.; Cirrone, G. A. P.; Cuttone, G.; Presti, D. Lo; Maccioni, G.; Pallotta, S.; Randazzo, N.; Romano, F.; Sipala, V.; Talamonti, C.; Vanzi, E.

    2017-02-01

    A prototype of proton Computed Tomography (pCT) system for hadron-therapy has been manufactured and tested in a 175 MeV proton beam with a non-homogeneous phantom designed to simulate high-contrast material. BI-SART reconstruction algorithms have been implemented with GPU parallelism, taking into account of most likely paths of protons in matter. Reconstructed tomography images with density resolutions r.m.s. down to 1% and spatial resolutions CT in hadron-therapy.

  4. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... a gantry, which rotates around the patient. The computer that processes the imaging information and monitor are ...

  5. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... a gantry, which rotates around the patient. The computer that processes the imaging information and monitor are ...

  6. Computed tomography versus invasive coronary angiography

    DEFF Research Database (Denmark)

    Napp, Adriane E; Haase, Robert; Laule, Michael

    2017-01-01

    OBJECTIVES: More than 3.5 million invasive coronary angiographies (ICA) are performed in Europe annually. Approximately 2 million of these invasive procedures might be reduced by noninvasive tests because no coronary intervention is performed. Computed tomography (CT) is the most accurate noninva...... angiography (ICA) is the reference standard for detection of CAD. • Noninvasive computed tomography angiography excludes CAD with high sensitivity. • CT may effectively reduce the approximately 2 million negative ICAs in Europe. • DISCHARGE addresses this hypothesis in patients with low...

  7. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... which are then displayed on a monitor. Special software can also generate three-dimensional (3-D) images ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ...

  8. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... which are then displayed on a monitor. Special software can also generate three-dimensional (3-D) images ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ...

  9. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... through the body, recording an image on photographic film or a special image recording plate . Bones appear ...

  10. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... images can be viewed on a computer monitor, printed on film or transferred to a CD or ... of the machine, the x-ray tube and electronic x-ray detectors are located opposite each other ...

  11. Paradoxical emboli: demonstration using helical computed tomography of the pulmonary artery associated with abdominal computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Delalu, P.; Ferretti, G.R.; Bricault, I.; Ayanian, D.; Coulomb, M. [Service Central de Radiologie et Imagerie Medicale, CHU Grenoble (France)

    2000-02-01

    We report the case of a 60-year-old woman with a recent history of a cerebrovascular accident. Because of clinical suspicion of pulmonary embolism and negative Doppler ultrasound findings of the lower limbs, spiral computed tomography of the pulmonary artery was performed and demonstrated pulmonary emboli. We emphasize the role of computed tomography of the abdomen, performed 3 min after the thoracic acquisition, which showed an unsuspected thrombus within the abdominal aorta and the left renal artery with infarction of the left kidney. Paradoxical embolism was highly suspected on computed tomography data and confirmed by echocardiography which demonstrated a patent foramen ovale. (orig.)

  12. Cervical diplomyelia revealed by computed tomography (CT)

    Energy Technology Data Exchange (ETDEWEB)

    Giordano, G.B.; Davidovits, P.; Cerisoli, M.; Giulioni, M.

    1982-05-01

    An unusual case of cervical diplomyelia diagnosed by Computed Tomography (CT) is reported. The usefulness of CT examination in the evaluation of spinal dysraphic defects is emphasized, though performed without CSF enhancement. Visualisation of spinal cord splitting in the absence of bony spicula allows the authors to differentiate between diplomyelia and diastematomyelia which have been often described by using both terms interchangeably.

  13. Computed tomography demonstration of cholecystogastric fistula

    Directory of Open Access Journals (Sweden)

    Chung Kuao Chou, MD, MPH

    2016-06-01

    Full Text Available Cholecystogastric fistula is a rare complication of chronic cholecystitis or long-standing cholelithiasis. It results from the gradual erosion of the approximated, chronically inflamed wall of the gall bladder and stomach with fistulous tract formation. The present case describes the direct visualization of a cholecystogastric fistula by computed tomography in a patient without prior biliary system complaints.

  14. Computed tomography in untreated congenital adrenal hyperplasia

    Energy Technology Data Exchange (ETDEWEB)

    Harinarayana, C.V.; Renu, G.; Ammini, A.C.; Khurana, M.L.; Ved, P.; Karmarkar, M.G.; Ahuja, M.M.S.; Berry, M. (AIIMS, New Delhi (India))

    1991-02-01

    Six children with untreated congenital adrenal hyperplasia (CAH) were examined by computed tomography (CT). Three cases demonstrated diffuse enlargement of both adrenal glands with preservation of normal configuration and two showed tumorous transformation in one of the enlarged glands. One had equivocal in this group (age 2 years) also showed bilateral hyperplasia. (orig.).

  15. Cone beam computed tomography in veterinary dentistry

    NARCIS (Netherlands)

    van Thielen, B.; Siguenza, F.; Hassan, B.

    2012-01-01

    The purpose of this study was to assess the feasibility of cone beam computed tomography (CBCT) in imaging dogs and cats for diagnostic dental veterinary applications. CBCT scans of heads of six dogs and two cats were made. Dental panoramic and multi-planar reformatted (MPR) para-sagittal reconstruc

  16. Cone beam computed tomography in veterinary dentistry

    NARCIS (Netherlands)

    van Thielen, B.; Siguenza, F.; Hassan, B.

    2012-01-01

    The purpose of this study was to assess the feasibility of cone beam computed tomography (CBCT) in imaging dogs and cats for diagnostic dental veterinary applications. CBCT scans of heads of six dogs and two cats were made. Dental panoramic and multi-planar reformatted (MPR) para-sagittal reconstruc

  17. Neutron computed tomography of rat lungs

    Energy Technology Data Exchange (ETDEWEB)

    Metzke, R W; Wall, W A [Institute for Computational Mechanics at Technische Universitaet Muenchen, 85747 Garching (Germany); Runck, H; Stahl, C A; Schneider, M; Guttmann, J [Department of Anesthesiology, Section for Experimental Anesthesiology, University Medical Center Freiburg, 79106 Freiburg (Germany); Schillinger, B; Calzada, E; Muehlbauer, M; Schulz, M [Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM-II) and Fakultaet fuer Physik E21 at Technische Universitaet Muenchen, 85748 Garching (Germany); Priebe, H-J, E-mail: metzke@lnm.mw.tum.d [Department of Anesthesiology, University Medical Center Freiburg, 79106 Freiburg (Germany)

    2011-01-07

    Using conventional methods, three-dimensional imaging of the lung is challenging because of the low contrast between air and tissue and the large differences in dimensions between various pulmonary structures. The small distal airway structures and the high air-to-tissue ratio of lung tissue require an imaging technique which reliably discriminates between air and water. The objective of this study was to assess whether neutron computed tomography would satisfy such a requirement. This method utilizes the unique characteristic of neutrons of directly interacting with the atomic nucleus rather than being scattered by the atomic shell. Neutron computed tomography was tested in rats and allowed differentiation of larger lung structures (e.g., lobes) and distal airways. Airways could be identified reliably down to the sixth bronchial generation, in some cases even down to the tenth generation. The lung could be stabilized for sufficiently long exposure times to achieve an image resolution of 50-60 {mu}m, which is the current physical resolution limit of the neutron computed tomography facility. Neutron computed tomography allowed excellent lung imaging without the need for additional tissue preparation or contrast media. The enhanced structural resolution obtained by applying this new research technique may improve understanding of lung physiology and respiratory therapy. (note)

  18. Parallel Computing for the Computed-Tomography Imaging Spectrometer

    Science.gov (United States)

    Lee, Seungwon

    2008-01-01

    This software computes the tomographic reconstruction of spatial-spectral data from raw detector images of the Computed-Tomography Imaging Spectrometer (CTIS), which enables transient-level, multi-spectral imaging by capturing spatial and spectral information in a single snapshot.

  19. Computed tomography of tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Noriko; Sato, Hiromi; Kawaguchi, Tetsuro; Fujita, Katsuzo; Tanaka, Makoto (Kobe Univ. (Japan). School of Medicine)

    1982-12-01

    Recently, tuberculous meningitis has become rather rare except in areas where tuberculosis is still endemic. Six adolescents and young adults with tuberculous meningitis were evaluated by means of serial computerized tomography (CT), and the results were correlated with the findings of surgical specimens or autopsies. All cases showed meningeal irritation and fever at onset. CSF cultures revealed the presence of tuberculous bacilli. Four cases advanced rapidly to the clinical stage III and expired in a short period-between two weeks to one month from onset. On initial CT scanning, the disappearance of the basal cistern was a characteristic finding in all these cases. With the progression, an enhancement of the basal cistern on contrast injection, a localized hypodensity in adjacent parenchyma, and symmetrical ventricular dilatation appeared. Two autopsied cases showed tuberculous granulomas with purulent materials, thickened meninges, and caseous necrosis in the parenchyma around the basal cistern. The other two cases progressed rather slowly. CT findings at Stage II showed multiple enhanced spots in the basal subcortical area following contrast injection. Tuberculous granulomas were identified in these parts by means of explorative craniotomy. The authors point out the pathognomonic CT findings of tuberculous meningitis and emphasize the necessity of serial CT for the early detection and management of tuberculous meningitis.

  20. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... detectors rotate around the patient. At the same time, the examination table is moving through the scanner, so that the x-ray beam follows a spiral path. A special computer program processes this series of pictures, or slices of the body, to ...

  1. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ...

  2. Single photon emission computed tomography/computed tomography for malignant otitis externa: lesion not shown on planar image.

    Science.gov (United States)

    Chen, Yu-Hung; Hsieh, Hung-Jen

    2013-01-01

    Malignant otitis externa is a severe and rare infection of the external acoustic meatus. Triphasic bone and (67)Ga scintigraphies are used to initial detect and follow-up the response of therapy. With single photon emission computed tomography/computed tomography images, the diagnostic sensitivity is higher. We presented a case with malignant otitis externa with initial negative planar scintigraphic finding. The lesion was detected by photon emission computed tomography/computed tomography images. We concluded that the photon emission computed tomography/computed tomography should be performed routinely for patients with suspected malignant otitis externa, even without evidence of lesion on planar images.

  3. Thermoluminescent dosimetry in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lara C, A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Unidad Legaria, Av. Legaria 694, Col. Irrigacion, 11500 Ciudad de Mexico (Mexico); Osorio V, M. [ISSSTE, Centro Medico Nacional 20 de Noviembre, Felix Cuevas 540, Col. del Valle, 03100 Ciudad de Mexico (Mexico); Hernandez O, O., E-mail: armando_lara_cam@yahoo.com.mx [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Ciudad de Mexico (Mexico)

    2016-10-15

    In this work we studied the dosimetry performed on CT scan in two different equipment, SOMATOM and Phillips, with 16 and 64 slice respectively. We used 51 pellets of lithium fluoride doped with magnesium and titanium (LiF: Mg, Ti) also knows as TLD-100 due to its physical properties and its easy of use, in this study, first analysis a batch of 56 pellets, but only 53 pellets were optimal for this study, cesium-137 was used as source irradiation, then proceeded to calibrate the batch with X-rays source, measuring the corresponding dose in a Farmers ionization chamber, then, we obtained a calibration curve, and we used as reference to calculation of the applied dose, finally designing ergonomic mesh, were it was deposited a TLD 100, placed in a regions of interest were made to each scan type. Once characterized our material proceeded to testing in 30 patients, which were irradiated with X-ray tube, whose operation was performed at 80, 120 kV with a current of 100, 300 and 400 m A according to scanning protocol. Overall we measured dose of 5 mGy to 53 mGy, these measurements reflect significant dose to can induced cancer, due previous reports published, that doses greater than 20 mGy there is a risk of developing cancer in the long term, but in practice when it assigned a medical diagnosis, there are no dose limits due to benefits patients, however, IAEA publish recommendations that allow us to carry out optimum handling of ionizing radiation, among these is the quality control of the tomography equipment that helps greatly reduce patient dose. (Author)

  4. Computed tomography of the spine

    Energy Technology Data Exchange (ETDEWEB)

    Haughton, V.M.; Williams, A.L.

    1982-01-01

    The book describes the computed tomographic (CT) techniques for imaging the different elements comprising the spinal column and canal. The use of intravenous and intrathecal contrast enhancement and of xenon enhancement is briefly mentioned. Reconstruction techniques and special problems regarding CT of the spine are presented. CT of the spinal cord, meninges and subarachnoid space, epidural space, intervertebral discs, facet joints, and vertebrae present normal anatomy, and several common pathologic conditions. (KRM)

  5. Computed tomography in mitochondrial cytopathy

    Energy Technology Data Exchange (ETDEWEB)

    Egger, J.; Kendall, B.E.

    1981-10-01

    The clinical and computed tomographic (CT) findings in 11 proven cases of mitochondrial cytopathy (mitochondrial myopathy, Kearns Sayre syndrome, ophthalmoplegia plus) were studied. The CT changes included focal low density lesions in the basal ganglia and white matter and atrophy which could be slight or diffuse and severe. Calcification has been described in the basal ganglia, but did not occur in our series. Serial CT showed progression of the abnormalities. The differential diagnosis is discussed.

  6. Computed tomography of thymic abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Schnyder, P.; Candardjis, G.

    1987-05-01

    Computed tomographic examinations of 38 patients with surgically and histologically proven diagnosis were reviewed. Twenty subjects (52%) had an invasive thymoma and 16% an hyperplastic thymus. Myasthenia gravis was present in 6 cases (16%) of thymic abnormalities, four (10,5%) with invasive thymoma and two (5%) with thymic hyperplasia. Graves' disease was also present in one case of thymic hyperplasia. We emphasize the contribution of CT to the diagnosis and the prognosis.

  7. Cerebral candidiasis. Computed tomography appearance

    Energy Technology Data Exchange (ETDEWEB)

    Chaabane, M.; Ladeb, M.F.; Bouhaouala, M.H.; Ben Hammouda, M.; Ataalah, R.; Gannouni, A.; Krifa, H.

    1989-07-01

    A three year old child who had been suffering from oral candidiasis since the age of 1 year presented with osteitis of the clavicle, 2 cerebral frontal abscesses and an occipital abscess which extended across the calvaria and was associated with osteolysis. Histological and microbiological studies following surgery confirmed the diagnosis of candidiasis in this girl who was found to have IgA immunodefinciency. The authors report the computed tomographic appearance of the cerebral lesions and review the literature. (orig.).

  8. Trip report: Marshall Space Center computed tomography

    Science.gov (United States)

    Harbour, J. R.; Andrews, M. K.

    BIR Inc. is a small company out of the Chicago area which sells equipment for producing images by tomography. They have built a relatively large instrument, called ACTIS, for NASA at the Marshall Space Center in Huntsville, Alabama and still gave access to this instrument. BIR has a grant from the Department of Energy (DOE) to determine the utility of computed tomography (CT) for characterization of nuclear and hazardous waste within the DOE complex. As part of this effort, the potential of this technique for obtaining images of canistered waste forms has been investigated. Funding for data acquisition was provided through this grant.

  9. Introducing Seismic Tomography with Computational Modeling

    Science.gov (United States)

    Neves, R.; Neves, M. L.; Teodoro, V.

    2011-12-01

    Learning seismic tomography principles and techniques involves advanced physical and computational knowledge. In depth learning of such computational skills is a difficult cognitive process that requires a strong background in physics, mathematics and computer programming. The corresponding learning environments and pedagogic methodologies should then involve sets of computational modelling activities with computer software systems which allow students the possibility to improve their mathematical or programming knowledge and simultaneously focus on the learning of seismic wave propagation and inverse theory. To reduce the level of cognitive opacity associated with mathematical or programming knowledge, several computer modelling systems have already been developed (Neves & Teodoro, 2010). Among such systems, Modellus is particularly well suited to achieve this goal because it is a domain general environment for explorative and expressive modelling with the following main advantages: 1) an easy and intuitive creation of mathematical models using just standard mathematical notation; 2) the simultaneous exploration of images, tables, graphs and object animations; 3) the attribution of mathematical properties expressed in the models to animated objects; and finally 4) the computation and display of mathematical quantities obtained from the analysis of images and graphs. Here we describe virtual simulations and educational exercises which enable students an easy grasp of the fundamental of seismic tomography. The simulations make the lecture more interactive and allow students the possibility to overcome their lack of advanced mathematical or programming knowledge and focus on the learning of seismological concepts and processes taking advantage of basic scientific computation methods and tools.

  10. Computed tomography of bones and joints.

    Science.gov (United States)

    Bruna, J; Sehr, A

    1989-01-01

    The monograph sums up the problem of CT diagnosis of bones and joints making use of predominantly the authors' own experience based on CT tests of more than 45,000 patients examined at the Department of Radiology, Charles University Medical Faculty of Hygiene teaching hospital in Prague in the years 1980-1988. Specific scans of the skeleton were made in 4,500 patients, mostly for suspicion or closer assessment of neoplasms (43.5%), the radicular lumbosacral syndrome (34.5%), and injuries (12%). The opening chapters sum up basic facts about the principle of computed tomography, the apparatus in use, the evaluation of CT images, CT radiation doses, and the patients' preparation for CT scanning. The use of contrast media is discussed with regard to the possible hazards involved and to the need to hear allergological opinion first. For spinal canal visualization non-ionogenic contrast media are used exclusively. The management of side reactions to contrast medium application is also reviewed. Indications for bone and joint computed tomography now comprise a whole series of traumatological, orthopaedic, oncological, rheumatological, neurological and rehabilitation conditions, each of which is discussed in detail in a separate chapter. CT anatomical studies offer the advantage of being applicable even in patients examined for other than bone or articular diseases. The option of simultaneous soft tissue assessment represents another advantage. The authors describe different anatomical structures in terms of CT images, some of them complete with dimensional and density values. The chapter on anomalies and developmental variants stresses the relevance of computed tomography for precise characteristics of clefts of the spinal column and facial bones and for the diagnosis of anomalies and dysplasias of the spinal column and the chest. A rare case of cephalothoracopagus is demonstrated. As for traumatology, computed tomography is found useful in diagnosing fractures of the

  11. The Western Denmark Cardiac Computed Tomography Registry

    DEFF Research Database (Denmark)

    Nielsen, Lene Hüche; Nørgaard, Bjarne Linde; Tilsted, Hans Henrik;

    2015-01-01

    -CCTR, showed that coronary CT angiographies accounted for only 23% of all nonregistered cardiac CTs, indicating >90% completeness of coronary CT angiographies in the WDHR-CCTR. The completeness of individual variables varied substantially (range: 0%-100%), but was >85% for more than 70% of all variables. Using......BACKGROUND: As a subregistry to the Western Denmark Heart Registry (WDHR), the Western Denmark Cardiac Computed Tomography Registry (WDHR-CCTR) is a clinical database established in 2008 to monitor and improve the quality of cardiac computed tomography (CT) in Western Denmark. OBJECTIVE: We...... expected numbers; and 4) positive predictive values as well as negative predictive values of 19 main patient and procedure variables. RESULTS: By December 31, 2012, almost 22,000 cardiac CTs with up to 40 variables for each procedure have been registered. Of these, 87% were coronary CT angiography...

  12. [Pneumothorax revealed by postoperative computed tomography].

    Science.gov (United States)

    Ikeda, Shizuka; Katori, Kiyoshi; Fujimoto, Minoru; Nitahara, Keiichi; Higa, Kazuo

    2005-11-01

    We report a case of pneumothorax revealed by postoperative computed tomography. A 39-year-old obese woman (height 153 cm, weight 70 kg) with fractures of the radius, ulna, clavicle, and femur in a traffic accident, was scheduled for osteosynthesis. Anesthesia was induced with thiopental and maintained with 50% nitrous oxide in oxygen and sevoflurane. The Spo2 decreased from 99% to 94% during the surgery. Bilateral chest sounds were symmetrical. The Spo2 increased to 100% after discontinuation of nitrous oxide. Pneumothorax was not evident on a postoperative chest X-ray, but computed tomography of the chest demonstrated right-sided pneumothorax. An ECG electrode had overlapped the fractured rib on the preoperative chest X-ray.

  13. Cone beam computed tomography in endodontic

    Energy Technology Data Exchange (ETDEWEB)

    Durack, Conor; Patel, Shanon, E-mail: conordurack1@hotmail.com [Unit of Endodontology, Department of Conservative Dentistry, King' s College London, London (United Kingdom)

    2012-07-01

    Cone beam computed tomography (CBCT) is a contemporary, radiological imaging system designed specifically for use on the maxillofacial skeleton. The system overcomes many of the limitations of conventional radiography by producing undistorted, three-dimensional images of the area under examination. These properties make this form of imaging particularly suitable for use in endodontic. The clinician can obtain an enhanced appreciation of the anatomy being assessed, leading to an improvement in the detection of endodontic disease and resulting in more effective treatment planning. In addition, CBCT operates with a significantly lower effective radiation dose when compared with conventional computed tomography (CT). The purpose of this paper is to review the current literature relating to the limitations and potential applications of CBCT in endodontic practice. (author)

  14. Contrast-induced nephropathy after computed tomography

    Directory of Open Access Journals (Sweden)

    Luciano da Silva Selistre

    2015-03-01

    Full Text Available Introduction: Contrast induced nephropathy is the third most prevalent preventable cause of acute kidney injury in hospitalized patients. It defined as an absolute increase in serum creatinine ≥ 0.5 mg/dL and relative ≥ 25% increase. Objective: We studied the risk factors to intravenous injection contrast nephropathy after computed tomography. Methods: We studied 400 patients prospectively. Results: The incidence of contrast induced nephropathy, with an absolute or a relative increase were 4.0% and 13.9%, respectively. Diabetes and cardiac failure were independent risk factors for CIN a relative increase de serum creatinine (O.R.: 3.5 [95% CI: 1.92-6.36], p < 0.01, 2.61 [95% CI: 1.14-6.03%], p < 0.05, respectively. Conclusions: We showed association between uses of intravenous injection contrast after computed tomography with acute injury renal, notably with diabetes and heart failure.

  15. Cone beam computed tomography in endodontics.

    Science.gov (United States)

    Durack, Conor; Patel, Shanon

    2012-01-01

    Cone beam computed tomography (CBCT) is a contemporary, radiological imaging system designed specifically for use on the maxillo-facial skeleton. The system overcomes many of the limitations of conventional radiography by producing undistorted, three-dimensional images of the area under examination. These properties make this form of imaging particularly suitable for use in endodontics. The clinician can obtain an enhanced appreciation of the anatomy being assessed, leading to an improvement in the detection of endodontic disease and resulting in more effective treatment planning. In addition, CBCT operates with a significantly lower effective radiation dose when compared with conventional computed tomography (CT). The purpose of this paper is to review the current literature relating to the limitations and potential applications of CBCT in endodontic practice.

  16. Computed tomography of ancient Egyptian mummies.

    Science.gov (United States)

    Harwood-Nash, D C

    1979-12-01

    This first report of the application of computed tomography (CT) to the study of ancient mummies, the desiccated brain of a boy and the body of a young woman within her cartonnage, shows that CT is uniquely suitable for the study of such antiquities, a study that does not necessitate destruction of the mummy or its cartonnage. Exquisite images result that are of great paleoanatomical, paleopathological, and archeological significance.

  17. Computed tomography and obstructive biliary disease.

    Science.gov (United States)

    Havrilla, T R; Haaga, J R; Alfidi, R J; Reich, N E

    1977-05-01

    Forty-four patients with confirmed biliary diseases were studied to determine the value of computed tomography (CT) in the diagnosis of biliary pathology. The results indicate that CT is useful and highly accurate in differentiating between obstructive (surgical) and nonobstructive (medical) disease entities. Of the cases with proved obstruction, 88% were correctly identified. All of the nonobstructive cases had positive CT correlation. In addition, the underlying cause of the occlusion was determined in the majority of cases.

  18. Cone Beam Computed Tomography - Know its Secrets

    OpenAIRE

    Kumar, Mohan; Shanavas, Muhammad; Sidappa, Ashwin; Kiran, Madhu

    2015-01-01

    Cone-beam computed tomography (CBCT) is an advanced imaging modality that has high clinical applications in the field of dentistry. CBCT proved to be a successful investigative modality that has been used for dental and maxillofacial imaging. Radiation exposure dose from CBCT is 10 times less than from conventional CT scans during maxillofacial exposure. Furthermore, CBCT is highly accurate and can provide a three-dimensional volumetric data in axial, sagittal and coronal planes. This article...

  19. Computed Tomography of Transverse Phase Space

    Energy Technology Data Exchange (ETDEWEB)

    Watts, A. [Fermilab; Johnstone, C. [Fermilab; Johnstone, J. [Fermilab

    2016-09-19

    Two computed tomography techniques are explored to reconstruct beam transverse phase space using both simulated beam and multi-wire profile data in the Fermilab Muon Test Area ("MTA") beamline. Both Filtered Back-Projection ("FBP") and Simultaneous Algebraic Reconstruction Technique ("SART") algorithms [2] are considered and compared. Errors and artifacts are compared as a function of each algorithm’s free parameters, and it is shown through simulation and MTA beamline profiles that SART is advantageous for reconstructions with limited profile data.

  20. Cone beam computed tomography use in orthodontics.

    Science.gov (United States)

    Nervina, J M

    2012-03-01

    Cone beam computed tomography (CBCT) is widely used by orthodontists to obtain three-dimensional (3-D) images of their patients. This is of value as malocclusion results from discrepancies in three planes of space. This review tracks the use of CBCT in orthodontics, from its validation as an accurate and reliable tool, to its use in diagnosing and treatment planning, and in assessing treatment outcomes in orthodontics.

  1. Encapsulating peritonitis: computed tomography and surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kadow, Juliana Santos; Fingerhut, Carla Jeronimo Peres; Fernandes, Vinicius de Barros; Coradazzi, Klaus Rizk Stuhr; Silva, Lucas Marciel Soares; Penachim, Thiago Jose, E-mail: vinicius.barros.fernandes@gmail.com [Pontificia Universidade Catolica de Campinas (PUC-Campinas), Campinas, SP (Brazil). Hospital e Maternidade Celso Pierro

    2014-07-15

    Sclerosing encapsulating peritonitis is a rare and frequently severe entity characterized by total or partial involvement of small bowel loops by a membrane of fibrous tissue. The disease presents with nonspecific clinical features of intestinal obstruction, requiring precise imaging diagnosis to guide the treatment. The present report emphasizes the importance of computed tomography in the diagnosis of this condition and its confirmation by surgical correlation. (author)

  2. Therapy response evaluation with positron emission tomography-computed tomography.

    Science.gov (United States)

    Segall, George M

    2010-12-01

    Positron emission tomography-computed tomography with F-18-fluorodeoxyglucose is widely used for evaluation of therapy response in patients with solid tumors but has not been as readily adopted in clinical trials because of the variability of acquisition and processing protocols and the absence of universal response criteria. Criteria proposed for clinical trials are difficult to apply in clinical practice, and gestalt impression is probably accurate in individual patients, especially with respect to the presence of progressive disease and complete response. Semiquantitative methods of determining tissue glucose metabolism, such as standard uptake value, can be a useful descriptor for levels of tissue glucose metabolism and changes in response to therapy if technical quality control measures are carefully maintained. The terms partial response, complete response, and progressive disease are best used in clinical trials in which the terms have specific meanings and precise definitions. In clinical practice, it may be better to use descriptive terminology agreed upon by imaging physicians and clinicians in their own practice.

  3. Computed tomography to quantify tooth abrasion

    Science.gov (United States)

    Kofmehl, Lukas; Schulz, Georg; Deyhle, Hans; Filippi, Andreas; Hotz, Gerhard; Berndt-Dagassan, Dorothea; Kramis, Simon; Beckmann, Felix; Müller, Bert

    2010-09-01

    Cone-beam computed tomography, also termed digital volume tomography, has become a standard technique in dentistry, allowing for fast 3D jaw imaging including denture at moderate spatial resolution. More detailed X-ray images of restricted volumes for post-mortem studies in dental anthropology are obtained by means of micro computed tomography. The present study evaluates the impact of the pipe smoking wear on teeth morphology comparing the abraded tooth with its contra-lateral counterpart. A set of 60 teeth, loose or anchored in the jaw, from 12 dentitions have been analyzed. After the two contra-lateral teeth were scanned, one dataset has been mirrored before the two datasets were registered using affine and rigid registration algorithms. Rigid registration provides three translational and three rotational parameters to maximize the overlap of two rigid bodies. For the affine registration, three scaling factors are incorporated. Within the present investigation, affine and rigid registrations yield comparable values. The restriction to the six parameters of the rigid registration is not a limitation. The differences in size and shape between the tooth and its contra-lateral counterpart generally exhibit only a few percent in the non-abraded volume, validating that the contralateral tooth is a reasonable approximation to quantify, for example, the volume loss as the result of long-term clay pipe smoking. Therefore, this approach allows quantifying the impact of the pipe abrasion on the internal tooth morphology including root canal, dentin, and enamel volumes.

  4. Positron Computed Tomography: Current State, Clinical Results and Future Trends

    Science.gov (United States)

    Schelbert, H. R.; Phelps, M. E.; Kuhl, D. E.

    1980-09-01

    An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends. (ACR)

  5. Computed tomography appearances of sclerosing encapsulating peritonitis

    Energy Technology Data Exchange (ETDEWEB)

    George, C. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom)]. E-mail: cheriangeorge@hotmail.com; Al-Zwae, K. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom); Nair, S. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom); Cast, J.E.I. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom)

    2007-08-15

    Sclerosing encapsulating peritonitis (SEP) is a serious complication of peritoneal dialysis (PD) characterized by thickened peritoneal membranes, which lead to decreased ultra-filtration and intestinal obstruction. Its early clinical features are nonspecific, and it is often diagnosed late following laparotomy and peritoneal biopsy, when the patient develops small bowel obstruction, which can be a life-threatening complication. However, this is changing with increasing awareness of computed tomography (CT) findings in SEP. CT can yield an early, non-invasive diagnosis that may improve patient outcome. We present a review of the CT appearances of SEP.

  6. Sparse Image Reconstruction in Computed Tomography

    DEFF Research Database (Denmark)

    Jørgensen, Jakob Sauer

    In recent years, increased focus on the potentially harmful effects of x-ray computed tomography (CT) scans, such as radiation-induced cancer, has motivated research on new low-dose imaging techniques. Sparse image reconstruction methods, as studied for instance in the field of compressed sensing...... and limitations of sparse reconstruction methods in CT, in particular in a quantitative sense. For example, relations between image properties such as contrast, structure and sparsity, tolerable noise levels, suficient sampling levels, the choice of sparse reconstruction formulation and the achievable image...

  7. Computed tomography in neuronal ceroid lipofuscinosis

    Energy Technology Data Exchange (ETDEWEB)

    Valavanis, A.; Schubiger, O.; Hayek, J.; Friede, R.L

    1981-01-01

    The computed tomography (CT) findings in a verified case of neuronal ceroid lipofuscinosis (NCL) are presented. CT revealed diffuse and severe cerebral atrophy, reflected by generalized subarachnoid space enlargement and symmetric ventricular dilatation. There was no evidence of abnormalities of the white matter. The CT features in our case of NCL correspond perfectly with the neuropathologic changes of the disease mentioned in the literature. Furthermore, CT is of considerable help in differentiating between those inherited metabolic brain diseases characterized primarily by white matter involvement and those presenting predominantly with changes of grey matter.

  8. Comparison on Computed Tomography using industrial items

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo

    2014-01-01

    In a comparison involving 27 laboratories from 8 countries, measurements on two common industrial items, a polymer part and a metal part, were carried out using X-ray Computed Tomography. All items were measured using coordinate measuring machines before and after circulation, with reference...... measurement uncertainties in the range 1.5–5.5 μm, showing a good stability over the 6 months of the circulation. The comparison has shown that CT measurements on the industrial parts used lie in the range 6–53 μm, with maximum values up to 158 μm....

  9. Tomography and spectroscopy as quantum computations

    CERN Document Server

    Miquel, C; Saraceno, M; Knill, E H; Laflamme, R; Negrevergne, C; Miquel, Cesar; Paz, Juan Pablo; Saraceno, Marcos; Knill, Emmanuel; Laflamme, Raymond; Negrevergne, Camille

    2001-01-01

    Determining the state of a system and measuring properties of its evolution are two of the most important tasks a physicist faces. For the first purpose one can use tomography, a method that after subjecting the system to a number of experiments determines all independent elements of the density matrix. For the second task, one can resort to spectroscopy, a set of techniques used to determine the spectrum of eigenvalues of the evolution operator. In this letter, we show that tomography and spectroscopy can be naturally interpreted as dual forms of quantum computation. We show how to adapt the simplest case of the well-known phase estimation quantum algorithm to perform both tasks, giving it a natural interpretation as a simulated scattering experiment. We show how this algorithm can be used to implement an interesting form of tomography by performing a direct measurement of the Wigner function of a quantum system. We present results of such measurements performed on a system of three qubits using liquid state...

  10. COMPUTED TOMOGRAPHY OF TOOTH RESORPTION IN CATS.

    Science.gov (United States)

    Lang, Linda G; Wilkinson, Thomas E; White, Tammy L; Farnsworth, Raelynn K; Potter, Kathleen A

    2016-09-01

    Tooth resorption is the most common dental disease in cats and can be a source of oral pain. The current clinical gold standard for diagnosis includes a combination of oral exam and dental radiography, however early lesions are not always detected. Computed tomography (CT) of the skull, including the dental arches, is a commonly performed diagnostic procedure, however the appearance of tooth resorption on CT and the diagnostic ability of CT to detect tooth resorption have not been evaluated. The purpose of this prospective, descriptive, diagnostic accuracy study was to characterize the CT appearance of tooth resorption in a sample of affected cats and to evaluate the sensitivity and specificity of CT for tooth resorption compared to the clinical gold standard of oral exam and intraoral dental radiography. Twenty-eight cat cadaver specimens were recruited for inclusion. Each specimen was evaluated using oral exam, intraoral dental radiography, and computed tomography (four different slice thicknesses). Each tooth was evaluated for the presence or absence of tooth resorption. Teeth with lesions and a subset of normal teeth were evaluated with histopathology. On CT, tooth resorption appeared as irregularly marginated hypoattenuating defects in the mineral attenuating tooth components, most commonly involving the root or cementoenamel junction. Sensitivity for CT detection of tooth resorption was fair to poor (42.2-57.7%) and specificity was good to excellent (92.8-96.3%). Findings from this study indicated that CT has high specificity but low sensitivity for detection of tooth resorption in cats.

  11. Computed tomography in pelvic and acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Born, H.; Schmidt, C.

    1988-06-01

    In a retrospective study we analyzed the results of 127 patients, who were examined not only by means of conventional radiography but also by means of computed tomography after a trauma of the pelvic. Our investigations were based upon such patients, to whom a definite diagnostic procedure of plain radiography had been performed. Therefore all polytraumatized patients were inapplicable. They were only examined by computed tomography because of other more important accompanying injuries of other body regions. We compared the results of 127 patients with pelvic trauma. The results of the CT were in accordance with the results of the plain radiography for 103 patients. The results of the CT concerning the availability and the localization of the fractures were basically coincident with the plain radiography for 22 patients, but the CT showed a higher degree of trauma and additional intraarticular fragments. Two isolated lesions of the sacroiliac joint could not be recognized by both methods. They could only be diagnosed by bone scintigraphy on the third day after trauma.

  12. SADMFR guidelines for the use of cone-beam computed tomography/ Digital Volume Tomography

    OpenAIRE

    Dula, Karl; Bornstein, Michael M.; Buser, Daniel; Dagassan-Berndt, Dorothea; Ettlin, Dominik A; Filippi, Andreas; Gabioud, François; Katsaros, Christos; Krastl, Gabriel; Lambrecht, J. Thomas; Lauber, Roland; Luebbers, Heinz-Theo; Pazera, Pawel; Türp, Jens C.

    2014-01-01

    Cone-Beam Computed Tomography (CBCT) has been introduced in 1998. This radiological imaging procedure has been provided for dentistry and is comparable to computed tomography (CT) in medicine. It is expected that CBCT will have the same success in dental diagnostic imaging as computed tomography had in medicine. Just as CT is responsible for a significant rise in radiation dose to the population from medical X-ray diagnostics, CBCT studies will be accompanied by a significant increase of the ...

  13. Computed Tomography Technology: Development and Applications for Defence

    Science.gov (United States)

    Baheti, G. L.; Saxena, Nisheet; Tripathi, D. K.; Songara, K. C.; Meghwal, L. R.; Meena, V. L.

    2008-09-01

    Computed Tomography(CT) has revolutionized the field of Non-Destructive Testing and Evaluation (NDT&E). Tomography for industrial applications warrants design and development of customized solutions catering to specific visualization requirements. Present paper highlights Tomography Technology Solutions implemented at Defence Laboratory, Jodhpur (DLJ). Details on the technological developments carried out and their utilization for various Defence applications has been covered.

  14. Use of high-resolution computed tomography and positron emission tomography/computed tomography in the management of stage IA adenocarcinoma.

    Science.gov (United States)

    Miyata, Yoshihiro; Tsutani, Yasuhiro; Okada, Morihito

    2012-01-01

    Preoperative determination of malignant behavior is critical in choosing suitable therapeutic strategies such as sublobar resection for patients with small lung cancers. The aim of present review was to evaluate high-resolution computed tomography and fluorodeoxyglucose-positron emission tomography/computed tomography as tools for management of clinical stage IA adenocarcinoma.

  15. Spatiotemporal computed tomography of dynamic processes

    Science.gov (United States)

    Kaestner, Anders; Münch, Beat; Trtik, Pavel; Butler, Les

    2011-12-01

    Modern computed tomography (CT) equipment allowing fast 3-D imaging also makes it possible to monitor dynamic processes by 4-D imaging. Because the acquisition time of various 3-D-CT systems is still in the range of at least milliseconds or even hours, depending on the detector system and the source, the balance of the desired temporal and spatial resolution must be adjusted. Furthermore, motion artifacts will occur, especially at high spatial resolution and longer measuring times. We propose two approaches based on nonsequential projection angle sequences allowing a convenient postacquisition balance of temporal and spatial resolution. Both strategies are compatible with existing instruments, needing only a simple reprograming of the angle list used for projection acquisition and care with the projection order list. Both approaches will reduce the impact of artifacts due to motion. The strategies are applied and validated with cold neutron imaging of water desorption from originally saturated particles during natural air-drying experiments and with x-ray tomography of a polymer blend heated during imaging.

  16. Imaging of Cardiac Valves by Computed Tomography

    Directory of Open Access Journals (Sweden)

    Gudrun Feuchtner

    2013-01-01

    Full Text Available This paper describes “how to” examine cardiac valves with computed tomography, the normal, diseased valves, and prosthetic valves. A review of current scientific literature is provided. Firstly, technical basics, “how to” perform and optimize a multislice CT scan and “how to” interpret valves on CT images are outlined. Then, diagnostic imaging of the entire spectrum of specific valvular disease by CT, including prosthetic heart valves, is highlighted. The last part gives a guide “how to” use CT for planning of transcatheter aortic valve implantation (TAVI, an emerging effective treatment option for patients with severe aortic stenosis. A special focus is placed on clinical applications of cardiac CT in the context of valvular disease.

  17. Advanced proton imaging in computed tomography

    CERN Document Server

    Mattiazzo, S; Giubilato, P; Pantano, D; Pozzobon, N; Snoeys, W; Wyss, J

    2015-01-01

    In recent years the use of hadrons for cancer radiation treatment has grown in importance, and many facilities are currently operational or under construction worldwide. To fully exploit the therapeutic advantages offered by hadron therapy, precise body imaging for accurate beam delivery is decisive. Proton computed tomography (pCT) scanners, currently in their R&D phase, provide the ultimate 3D imaging for hadrons treatment guidance. A key component of a pCT scanner is the detector used to track the protons, which has great impact on the scanner performances and ultimately limits its maximum speed. In this article, a novel proton-tracking detector was presented that would have higher scanning speed, better spatial resolution and lower material budget with respect to present state-of-the-art detectors, leading to enhanced performances. This advancement in performances is achieved by employing the very latest development in monolithic active pixel detectors (to build high granularity, low material budget, ...

  18. Analysis of airways in computed tomography

    DEFF Research Database (Denmark)

    Petersen, Jens

    Chronic Obstructive Pulmonary Disease (COPD) is major cause of death and disability world-wide. It affects lung function through destruction of lung tissue known as emphysema and inflammation of airways, leading to thickened airway walls and narrowed airway lumen. Computed Tomography (CT) imaging...... have become the standard with which to assess emphysema extent but airway abnormalities have so far been more challenging to quantify. Automated methods for analysis are indispensable as the visible airway tree in a CT scan can include several hundreds of individual branches. However, automation...... of scan on airway dimensions in subjects with and without COPD. The results show measured airway dimensions to be affected by differences in the level of inspiration and this dependency is again influenced by COPD. Inspiration level should therefore be accounted for when measuring airways, and airway...

  19. Findings of computed tomography in intracranial tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Jo, H. G.; Bae, K. S.; Lee, H. K.; Kwon, K. H.; Kim, K. J. [Soonchunhyang University College of Medicine, Seoul (Korea, Republic of)

    1983-12-15

    In intracranial tuberculosis, the Computed Tomography (CT) is a new radiological technique which is helpful in diagnosis and determining the location, extents of the lesion. It can also make it possible to assess the presence and degree of the complications and to evaluate the effectiveness of treatment. 25 cases of clinically proven intracranial tuberculosis were studied by CT, in Soonchunhyang hospital from Jun. 1980 to Jun. 1983. The result were as follows; 1. 4 cases were normal in CT finding, despite of the clinically proven tuberculous meningitis. 2. Total or partial obliteration of cisterns were observed in 13 cases. 3. Intense abnormal contrast enhancement of the cisterns were observed in 8 cases. 4. 19 cases show moderate to marked ventricular dilatation. 5. 2 cases of cerebral infarction were observed. 6. One case of tuberculoma was observed.

  20. Computed Tomography in the Modern Slaughterhouse

    DEFF Research Database (Denmark)

    Mosbech, Thomas Hammershaimb

    of technology. Recently, the use of X-ray computed tomography (CT) coupled with methods from image analysis has been introduced as a powerful means to optimise production, by providing detailed information on the raw materials. This thesis covers two aspects of the application of CT in the modern abattoir...... concerns measurements of each single carcass, to improve the raw material utilisation by individually adapted processing. Measurements performed online in the abattoir demand fast, robust and cost-effective imaging. We propose a tomographic reconstruction algorithm, enabling a substantial reduction...... of the subject-specific X-ray data needed to produce high quality images for accurate measurements. This is very beneficial for the abattoirs, as a reduction in acquired data translates directly into higher speed and a lower cost. The thesis demonstrates the great potential of CT as a technology for improving...

  1. Computed Tomography (CT) Perfusion in Abdominal Cancer

    DEFF Research Database (Denmark)

    Hansen, Martin Lundsgaard; Norling, Rikke; Lauridsen, Carsten

    2013-01-01

    Computed Tomography (CT) Perfusion is an evolving method to visualize perfusion in organs and tissue. With the introduction of multidetector CT scanners, it is now possible to cover up to 16 cm in one rotation, and thereby making it possible to scan entire organs such as the liver with a fixed...... table position. Advances in reconstruction algorithms make it possible to reduce the radiation dose for each examination to acceptable levels. Regarding abdominal imaging, CT perfusion is still considered a research tool, but several studies have proven it as a reliable non-invasive technique...... for assessment of vascularity. CT perfusion has also been used for tumor characterization, staging of disease, response evaluation of newer drugs targeted towards angiogenesis and as a method for early detection of recurrence after radiation and embolization. There are several software solutions available...

  2. Computed tomography in metastatic renal cell carcinoma.

    Science.gov (United States)

    Griffin, Nyree; Grant, Lee Alexander; Bharwani, Nishat; Sohaib, S Aslam

    2009-08-01

    Recent developments in chemotherapy have resulted in several new drug treatments for metastatic renal cell carcinoma (RCC). These therapies have shown improved progression-free survival and are applicable to many more patients than the conventional cytokine-based treatments for metastatic RCC. Consequently imaging is playing a greater part in the management of such patients. Computed tomography (CT) remains the primary imaging modality with other imaging modalities playing a supplementary role. CT is used in the diagnosis and staging of metastatic RCC. It is used in the follow-up of patients after nephrectomy, in assessing the extent of metastatic disease, and in evaluating response to treatment. This review looks at the role of CT in patients with metastatic RCC and describes the appearances of metastatic RCC before and following systemic therapy.

  3. Computed tomography of the abnormal thymus

    Energy Technology Data Exchange (ETDEWEB)

    Baron, R.L.; Lee, J.K.T.; Sagel, S.S.; Levitt, R.G.

    1982-01-01

    Computed tomography (CT) should be the imaging method of choice following plain chest radiographs when a suspected thymic abnormality requires further evaluation. Based upon a six-year experience, including the evaluation of 25 patients with thymic pathology, CT was found useful in suggesting or excluding a diagnosis of thymoma and in distinguishing thymic hyperplasis from thymoma in patients with myasthenia gravis. The thickness of the thymic lobes determined by CT was found to be a more accurate indicator of infiltrative disease (thymic hyperplasia and lymphoma) than the width. CT was helpful in differentiating benign thymic cysts from solid tumors, and in defining the extent of a thymic neoplasms. On occasion, CT may suggest the specific histologic nature of a thymic lesion.

  4. Reconstructing cetacean brain evolution using computed tomography.

    Science.gov (United States)

    Marino, Lori; Uhen, Mark D; Pyenson, Nicholas D; Frohlich, Bruno

    2003-05-01

    Until recently, there have been relatively few studies of brain mass and morphology in fossil cetaceans (dolphins, whales, and porpoises) because of difficulty accessing the matrix that fills the endocranial cavity of fossil cetacean skulls. As a result, our knowledge about cetacean brain evolution has been quite limited. By applying the noninvasive technique of computed tomography (CT) to visualize, measure, and reconstruct the endocranial morphology of fossil cetacean skulls, we can gain vastly more information at an unprecedented rate about cetacean brain evolution. Here, we discuss our method and demonstrate it with several examples from our fossil cetacean database. This approach will provide new insights into the little-known evolutionary history of cetacean brain evolution.

  5. Computed tomography findings of malignant pleural mesothelioma

    Energy Technology Data Exchange (ETDEWEB)

    Shiota, Yutaro; Sato, Toshio; Yamaguchi, Kazuo; Ono, Tetsuya; Kaji, Masaro; Niiya, Harutaka (Kure Kyosai Hospital, Hiroshima (Japan))

    1994-04-01

    Computed tomography (CT) findings were assessed in 7 patients with malignant mesothelioma. CT findings were also reviewed in 9 patients with lung cancer and pleuritis carcinomatosa and in 11 patients with tuberculous pleuritis. Five patients with malignant mesothelioma underwent CT scans twice, on admission and from 1 to 7 months after admission. Tuberculous pleuritis could be distinguished from pleuritis carcinomatosa and malignant mesothelioma by the presence or absence of pleural nodularity and chest wall invasion. Although it was difficult to identify specific CT features clearly distinguishing malignant mesothelioma from pleuritis carcinomatosa, characteristic findings of malignant mesothelioma appeared to include the rapid development and progression of pleural rind and a tendency to spread directly into the chest wall. We divided the pleural into the four regions; upper anterior, upper posterior, lower anterior and lower posterior regions. Pleural changes were more frequently seen in the lower pleural regions than in the upper pleural regions in malignant mesothelioma. (author).

  6. Ultra-high resolution computed tomography imaging

    Energy Technology Data Exchange (ETDEWEB)

    Paulus, Michael J. (Knoxville, TN); Sari-Sarraf, Hamed (Knoxville, TN); Tobin, Jr., Kenneth William (Harriman, TN); Gleason, Shaun S. (Knoxville, TN); Thomas, Jr., Clarence E. (Knoxville, TN)

    2002-01-01

    A method for ultra-high resolution computed tomography imaging, comprising the steps of: focusing a high energy particle beam, for example x-rays or gamma-rays, onto a target object; acquiring a 2-dimensional projection data set representative of the target object; generating a corrected projection data set by applying a deconvolution algorithm, having an experimentally determined a transfer function, to the 2-dimensional data set; storing the corrected projection data set; incrementally rotating the target object through an angle of approximately 180.degree., and after each the incremental rotation, repeating the radiating, acquiring, generating and storing steps; and, after the rotating step, applying a cone-beam algorithm, for example a modified tomographic reconstruction algorithm, to the corrected projection data sets to generate a 3-dimensional image. The size of the spot focus of the beam is reduced to not greater than approximately 1 micron, and even to not greater than approximately 0.5 microns.

  7. Inter laboratory comparison on Industrial Computed Tomography

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo

    An interlaboratory comparison on industrial X-ray Computed Tomography (CT) was organized by the Centre for Geometrical Metrology (CGM), Department of Mechanical Engineering, Technical University of Denmark (DTU) and carried out within the project “Centre for Industrial Application of CT scanning...... - CIA-CT”. In the comparison, 27 laboratories from 8 countries were involved, and CT scanned two items selected among common industrial parts: a polymer part and a metal part. Altogether, 27 sets of items were circulated in parallel to the participants. Different measurands are considered, encompassing...... influence from the surrounding wall thickness on the measurement of roundness was documented for the metal item. The comparison shows that CT scanning on small industrial parts, generally speaking, is connected with uncertainties in the range 8-53 μm, as compared to an uncertainty range of 1.5-5.5 μm using...

  8. [Peripheral lung adenocarcinoma versus squamous cell carcinoma: evaluation with first-pass perfusion imaging using 64-detector row CT].

    Science.gov (United States)

    Li, Yuan; Yang, Zhigang; Chen, Tianwu; Yu, Jianqun; Deng, Yuping; Li, Zhenlin

    2009-04-01

    The aim of this study was to elucidate the characteristics of time attenuation curve and CT perfusion parameters for pulmonary adenocarcinomas and squamous cell carcinomas. 58 cases of pulmonary adenocarcinomas and 27 cases of squamous cell carcinomas underwent first pass CT perfusion imaging with 64-row MDCT. Data were analyzed using commercial software to generate time attenuation curve (TAC) and CT perfusion parameters, including perfusion, peak enhanced (PE), time to peak (TTP), and blood volume (BV). For TAC, there were 36.2% of type I and 63.8% of type II in adenocarcinomas, while there were 22.2% of type I and 77.8% of type II in squamous cell carcinomas. There was not significant difference (P>0.05). Perfusion, PE, TTP and BV of adenocarcinomas were 63.2 +/- 45.4 ml x min(-1) x ml(-1), 60.2 +/- 46.6 Hu, 34.8 +/- 10.2 s and 34.3 +/- 23.6 ml x 100 g(-1), respectively, while 54.3 +/- 50.2 ml x min(-1) x ml(-1), 48.5 +/- 34.9 Hu, 36.1 +/- 11.2 s and 27.6 +/- 21.7 ml x 100 g(-1), for squamous cell carcinoma, respectively. No significant differences were found between groups (P>0.05). No significant differences in TAC and CT perfusion parameters were found between adenocarcinomas and squamous cell carcinomas.

  9. Intravenous coronary angiography using electron beam computed tomography

    NARCIS (Netherlands)

    Rensing, B J; Bongaerts, A H; van Geuns, R J; van Ooijen, P M; Oudkerk, M; de Feyter, P J

    1999-01-01

    Intravenous coronary angiography with electron beam computed tomography (EBCT) allows for the noninvasive visualisation of coronary arteries. With dedicated computer hardware and software, three-dimensional renderings of the coronary arteries, veins, and other cardiac structures can be constructed f

  10. Cone beam computed tomography in Endodontics - a review

    NARCIS (Netherlands)

    Patel, S.; Durack, C.; Abella, F.; Shemesh, H.; Roig, M.; Lemberg, K.

    2015-01-01

    Cone beam computed tomography (CBCT) produces undistorted three-dimensional information of the maxillofacial skeleton, including the teeth and their surrounding tissues with a lower effective radiation dose than computed tomography. The aim of this paper is to: (i) review the current literature on

  11. Computed tomography and magnetic resonance findings in lipoid pneumonia.

    OpenAIRE

    Bréchot, J M; Buy, J.N.; Laaban, J P; Rochemaure, J

    1991-01-01

    A case of exogenous lipoid pneumonia was documented by computed tomography and magnetic resonance imaging. Although strongly suggesting the presence of fat on T1 weighted images, magnetic resonance does not produce images specific for this condition. Computed tomography is the best imaging modality for its diagnosis.

  12. Computed tomography in traumatic defects of the diaphragm.

    Science.gov (United States)

    Demos, T C; Solomon, C; Posniak, H V; Flisak, M J

    1989-03-01

    Two patients with traumatic diaphragmatic defects visible on computed tomography are presented. The diagnosis was delayed for several years in both patients. The diagnosis of these acquired diaphragmatic defects is often difficult. Computed tomography can lead to earlier diagnosis by demonstrating the defect in some patients when radiographic studies are not diagnostic.

  13. Diagnosis of lumbar disc hernia with computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizumi, Atsuro; Ohira, Nobuhiro; Ojima, Tadashi; Oshida, Midori; Horaguchi, Mitsuru (Tohoku Rosai Hospital, Sendai (Japan))

    1982-07-01

    Results of computed tomography performed on patients with clinically diagnosed hernia were compared with those of myelography and operative findings. This comparative study suggested that computed tomography is quite different from other methods and very useful in diagnosis of hernia. Some cases of hernia were shown, and the characteristics of CT were reviewed.

  14. Cone beam computed tomography in Endodontics - a review

    NARCIS (Netherlands)

    Patel, S.; Durack, C.; Abella, F.; Shemesh, H.; Roig, M.; Lemberg, K.

    2015-01-01

    Cone beam computed tomography (CBCT) produces undistorted three-dimensional information of the maxillofacial skeleton, including the teeth and their surrounding tissues with a lower effective radiation dose than computed tomography. The aim of this paper is to: (i) review the current literature on t

  15. X-Ray Computed Tomography for Advanced Materials and Processes.

    Science.gov (United States)

    1992-06-30

    percent. In this example, we have assumed $I M, $5(X)K and $200K CT systems operating at 10 percent of the capital investment per year for maintenance...Computed Tomo &:aphy of Composites," WRDC-TR-90-4014, July 1990. 5. P. Burstein and R. H. Bossi, "A Guide to Computed Tomography System Specifications," WRDC...Lannutti, "Applications of High- Resolution Computed Tomography," Proceedings of the 1991 Industrial Computed Tomography II Topical Conference, May 20-24

  16. Micro computed tomography for vascular exploration

    Directory of Open Access Journals (Sweden)

    Zhuang Zhen W

    2010-03-01

    Full Text Available Abstract Vascular exploration of small animals requires imaging hardware with a very high spatial resolution, capable of differentiating large as well as small vessels, in both in vivo and ex vivo studies. Micro Computed Tomography (micro-CT has emerged in recent years as the preferred modality for this purpose, providing high resolution 3D volumetric data suitable for analysis, quantification, validation, and visualization of results. The usefulness of micro-CT, however, can be adversely affected by a range of factors including physical animal preparation, numerical quantification, visualization of results, and quantification software with limited possibilities. Exacerbating these inherent difficulties is the lack of a unified standard for micro-CT imaging. Most micro-CT today is aimed at particular applications and the software tools needed for quantification, developed mainly by imaging hardware manufacturers, lack the level of detail needed to address more specific aims. This review highlights the capabilities of micro-CT for vascular exploration, describes the current state of imaging protocols, and offers guidelines and suggestions aimed at making micro-CT more accurate, replicable, and robust.

  17. Radiation doses from computed tomography in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, J.E.M.; Tingey, D.R.C

    1997-11-01

    Recent surveys in various countries have shown that computed tomography (CT) is a significant and growing contributor to the radiation dose from diagnostic radiology. Australia, with 332 CT scanners (18 per million people), is well endowed with CT equipment compared to European countries (6 to 13 per million people). Only Japan, with 8500 units (78 per million people), has a significantly higher proportion of CT scanners. In view of this, a survey of CT facilities, frequency of examinations, techniques and patient doses has been performed in Australia. It is estimated that there are 1 million CT examinations in Australia each year, resulting in a collective effective dose of 7000 Sv and a per caput dose of 0.39 mSv. This per caput dose is much larger than found in earlier studies in the UK and New Zealand but is less than 0.48 mSv in Japan. Using the ICRP risk factors, radiation doses from CT could be inducing about 280 fatal cancers per year in Australia. CT is therefore a significant, if not the major, single contributor to radiation doses and possible risk from diagnostic radiology. (authors) 28 refs., 11 tabs., 10 figs.

  18. Dedicated breast computed tomography: Basic aspects

    Energy Technology Data Exchange (ETDEWEB)

    Sarno, Antonio; Mettivier, Giovanni, E-mail: mettivier@na.infn.it; Russo, Paolo [Dipartimento di Fisica, Università di Napoli Federico II, Via Cintia, Napoli I-80126, Italy and INFN Sezione di Napoli, Napoli I-80126 (Italy)

    2015-06-15

    X-ray mammography of the compressed breast is well recognized as the “gold standard” for early detection of breast cancer, but its performance is not ideal. One limitation of screening mammography is tissue superposition, particularly for dense breasts. Since 2001, several research groups in the USA and in the European Union have developed computed tomography (CT) systems with digital detector technology dedicated to x-ray imaging of the uncompressed breast (breast CT or BCT) for breast cancer screening and diagnosis. This CT technology—tracing back to initial studies in the 1970s—allows some of the limitations of mammography to be overcome, keeping the levels of radiation dose to the radiosensitive breast glandular tissue similar to that of two-view mammography for the same breast size and composition. This paper presents an evaluation of the research efforts carried out in the invention, development, and improvement of BCT with dedicated scanners with state-of-the-art technology, including initial steps toward commercialization, after more than a decade of R and D in the laboratory and/or in the clinic. The intended focus here is on the technological/engineering aspects of BCT and on outlining advantages and limitations as reported in the related literature. Prospects for future research in this field are discussed.

  19. Computed tomography characterisation of additive manufacturing materials.

    Science.gov (United States)

    Bibb, Richard; Thompson, Darren; Winder, John

    2011-06-01

    Additive manufacturing, covering processes frequently referred to as rapid prototyping and rapid manufacturing, provides new opportunities in the manufacture of highly complex and custom-fitting medical devices and products. Whilst many medical applications of AM have been explored and physical properties of the resulting parts have been studied, the characterisation of AM materials in computed tomography has not been explored. The aim of this study was to determine the CT number of commonly used AM materials. There are many potential applications of the information resulting from this study in the design and manufacture of wearable medical devices, implants, prostheses and medical imaging test phantoms. A selection of 19 AM material samples were CT scanned and the resultant images analysed to ascertain the materials' CT number and appearance in the images. It was found that some AM materials have CT numbers very similar to human tissues, FDM, SLA and SLS produce samples that appear uniform on CT images and that 3D printed materials show a variation in internal structure.

  20. Portable Digital Radiography and Computed Tomography Manual

    Energy Technology Data Exchange (ETDEWEB)

    2007-11-01

    This user manual describes the function and use of the portable digital radiography and computed tomography (DRCT) scanner. The manual gives a general overview of x-ray imaging systems along with a description of the DRCT system. An inventory of the all the system components, organized by shipping container, is also included. In addition, detailed, step-by-step procedures are provided for all of the exercises necessary for a novice user to successfully collect digital radiographs and tomographic images of an object, including instructions on system assembly and detector calibration and system alignment. There is also a short section covering the limited system care and maintenance needs. Descriptions of the included software packages, the DRCT Digital Imager used for system operation, and the DRCT Image Processing Interface used for image viewing and tomographic data reconstruction are given in the appendixes. The appendixes also include a cheat sheet for more experienced users, a listing of known system problems and how to mitigate them, and an inventory check-off sheet suitable for copying and including with the machine for shipment purposes.

  1. Computed Tomography Following Body Stuffing Heroin

    Directory of Open Access Journals (Sweden)

    Sean P. Nordt

    2015-12-01

    Full Text Available A 37-year-old male presented to the emergency department (ED in police custody for “medical clearance” before being taken to jail. The patient was approached by police officers for suspicion of selling illicit drugs. When approached by police he ran away and was witnessed to swallow several small plastic baggies suspected to contain heroin. He was apprehended and brought to the ED. On arrival, he was asymptomatic with a blood pressure 144/83mmHg, heart rate 67bpm, respiratory rate of 19bpm, oxygen saturation of 99% on room air and afebrile. A Glasgow coma score was 15 and he was alert and oriented to person, place and time. Patient had a negative review of systems. On physical examination pupils were 4mm and reactive to light, lungs clear to auscultation and had normal respiratory rate with normal cardiovascular exam. Abdomen was soft, non-tender and non-distended with present bowel sounds. The patient admitted to ingesting approximately 20 packets of heroin to avoid being charged with possession. The patient declined activated charcoal and whole bowel irrigation (WBI with polyethylene glycol-electrolyte solution (PEG-ELS. The patient declined a urine toxicology immunoassay screen. A computed tomography (CT of his abdomen with contrast was obtained and read as normal except for a cluster of foreign bodies within the distal stomach likely contained within a plastic bag.

  2. Virtual computed tomography cystoscopy in bladder pathologies

    Directory of Open Access Journals (Sweden)

    Halil Arslan

    2006-04-01

    Full Text Available OBJECTIVE: Assessed the usefulness of virtual cystoscopy performed with multidetector computed tomography (CT in patients with different urinary bladder pathologies compared to the conventional cystoscopy. MATERIALS AND METHODS: Eighteen patients with different bladder pathologies, which consisted of 11 tumors, 3 diverticula, 2 trabecular changes and 2 stones, were assessed with conventional cystoscopy and virtual CT cystoscopy. The results of virtual CT cystoscopy were compared with the findings of conventional cystoscopy. We determined the detection rate and positive predictive value of CT imaging based virtual cystoscopy in the diagnosis of urinary bladder lesions. RESULTS: CT scanning was well tolerated by all patients, and no complications occurred. Images in 16 (88% of the 18 virtual cystoscopic examinations were either of excellent or good quality. All tumors except one, 2 trabecular changes and 2 stones were characterized with similar findings in the both of methods. The masses ranged from 0.4 to 7.0 cm in diameter. While conventional cystoscopy could not evaluate interior part of the diverticulum, virtual CT cystoscopy could demonstrate clearly within it. There were no false-positive findings in our series. CONCLUSION: Virtual CT cystoscopy is a promising technique to be used in the detection of bladder lesions. It should be considered especially at the evaluation of bladder diverticula. In the future, it may be possible or even advantageous to incorporate into the imaging algorithm for evaluation of bladder lesion.

  3. Virtual computed tomography cystoscopy in bladder pathologies

    Energy Technology Data Exchange (ETDEWEB)

    Arslan, Halil; Ceylan, Kadir; Harman, Mustafa; Yilmaz, Yuksel; Temizoz, Osman; Can, Saban [Yuzuncu Yil University School of Medicine, Van (Turkey). Dept. of Radiology and Urology]. E-mail: drhalilarslan@hotmail.com

    2006-03-15

    Objective: assessed the usefulness of virtual cystoscopy performed with multidetector computed tomography (CT) in patients with different urinary bladder pathologies compared to the conventional cystoscopy.Materials and methods: eighteen patients with different bladder pathologies, which consisted of 11 tumors, 3 diverticula, 2 trabecular changes and 2 stones, were assessed with conventional cystoscopy and virtual CT cystoscopy. The results of virtual CT cystoscopy were compared with the findings of conventional cystoscopy. We determined the detection rate and positive predictive value of CT imaging based virtual cystoscopy in the diagnosis of urinary bladder lesions. Results: CT scanning was well tolerated by all patients, and no complications occurred. Images in 16 (88%) of the 18 virtual cystoscopic examinations were either of excellent or good quality. All tumors except one, 2 trabecular changes and 2 stones were characterized with similar findings in the both of methods. The masses ranged from 0.4 to 7.0 cm in diameter. While conventional cystoscopy could not evaluate interior part of the diverticulum, virtual CT cystoscopy could demonstrate clearly within it. There were no false-positive findings in our series. Conclusion: virtual CT cystoscopy is a promising technique to be used in the detection of bladder lesions. It should be considered especially at the evaluation of bladder diverticula. In the future, it may be possible or even advantageous to incorporate into the imaging algorithm for evaluation of bladder lesion. (author)

  4. Application of computed tomography to spinal disorders

    Energy Technology Data Exchange (ETDEWEB)

    Sha, N.; Kurihara, A.; Kataoka, O. (Kobe Univ. (Japan). School of Medicine)

    1980-08-01

    The axial tomographic examination of the spine and its soft tissues is now readily available for orthopaedic surgery. If the appropriate conditions are maintained, computed tomography (CT) can provide useful information concerning the diagnosis and the treatment of spinal diseases. There are, however, some pitfalls in interpreting CT scans: 1) the existence of the lesion may be masked, and 2) its extent and configuration may be over- or under-evaluated depending on such technical factors as the slicing level, the slicing angle, the window width, and the window level. Experimental studies were carried out on a plaster of Paris model of the spine and a cadaver spine to determine the appropriate technical factors by which the CT (EMI whole body CT scanner 5005) can be applied accurately to a diseased spine. The factors obtained were then applied in examining ninety-nine patients with various spinal disorders. Window levels ranging between 100 and 150 were found to be most appropriate. The slicing angle should be 90/sup 0/, or perpendicular to the long axis of the object under study. However, deviations of +10 or -10 degrees are acceptable. The CT view of the spine may be divided into two patterns at the cervical and thoracic levels and into three patterns at the lumbar level. In addition, the usefulness and the diagnostic value of CT for various spinal problems are discussed based on our clinical material.

  5. Computed tomography in acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Loevblad, Karl-Olof [HUG-Geneva University Hospital, Geneva University Medical School, Department of Neuroradiology, Department of Imaging and Medical Informatics, Geneva (Switzerland); Baird, Alison E. [SUNY Downstate Medical Center, Cerebrovascular Disease and Stroke, 450 Clarkson Avenue, Box 1213, Brooklyn, NY (United States)

    2010-03-15

    Stroke remains the third most important cause of mortality in industrialized countries; this has prompted research for improvements in both diagnostic and therapeutic strategies for patients with signs of acute cerebral ischemia. Over the last decade, there has been a parallel in progress in techniques in both diagnostic and therapeutic options. While previously only used for excluding hemorrhage, imaging now has the possibility to detect ischemia, vascular occlusion, as well as detect tissue at risk in one setting. It should also allow to monitor treatment and predict/exclude therapeutic complications. Parallel to advances in magnetic resonance imaging of stroke, computed tomography has improved immensely over the last decade due to the development of CT scanners that are faster and that allow to acquire studies such as CT perfusion or CT angiography in a reliable way. CT can detect many signs that might help us detect impending signs of massive infarction, but we still lack the experience to use these alone to prevent a patient from benefitting from possible therapy. (orig.)

  6. Application of computed tomography in paleoanthropological research

    Institute of Scientific and Technical Information of China (English)

    Xiujie Wu; Lynne A.Schepartz

    2009-01-01

    Hominin fossils are the most important materials for exploring questions about human origins and evolution. Because human fossils are very rare, it is impossible to use highly destructive techniques in order to study their morphology. Traditional analyses can only rely on the information gained from the study of the external morphology of specimens, and these approaches limited the study of human evolution. The application of computed tomography (CT) has facilitated major developments in paleoanthropology. To date, few studies on Chinese hominin fossils have used CT scanning methodology, but this is rapidly changing. In order to better understand the appli-cation of CT methodology in paleoanthropology, we review the applications of CT scanning on hominin fossils throughout the world.Studies examined include virtual fossil reconstruction, the use of endocasts to elucidate brain morphology, biomechanical analyses of bone distribution, imaging of mummies and research on early human health, and skeletal and dental microanatomical research.2009 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.

  7. Computed tomography of the orbital lesions

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seong Eon; Suh, Soo Jhi; Kim, Ho Kyun; Kim, Soon Yong [Kyung Hee University School of Medicine, Seoul (Korea, Republic of)

    1980-06-15

    The use of computed tomography in investigation of orbital lesions was of value for the localization of the lesions as well as making the specific diagnosis. We advocated the combined use of transverse axial section and contrast enhancement in CT as a routine procedure often including coronal section in the diagnosis of orbital lesions because of its usefulness and more precise three dimensional imaging. The authors examined 68 patients with various ophthalmic problems by EMI-CT scanner 5005 from October 1977 to November 1979. Fifty one orbital lesions out of 68 CT scans were analyzed by CT, angiography and operative findings and results were as follows; 1. Among 43 males and 25 females, their age range was from 4 months to 66 years with the most frequent age group of first decade (17 cases; 25%) 2. The distribution of the lesions was mucocele, pseudotumor, optic nerve atrophy, metastasis, lacrimal gland tumor, persistent hypertrophic primary vitreous, granulosa cell myoblastoma, hemangioma in order with 13 malignancies (25%). 3. It was difficult to differentiate pathological diagnosis of the lesions, but the character of the lesions was determined by its characteristic location, and its relationship to eyeball, optic nerve, extraocular muscles and bony orbit. 4. It was thought that more accurate diagnosis of orbital lesions could be made by development of CT scanner having fine matrix, short time exposure and thin slice in the future.

  8. Portable Digital Radiography and Computed Tomography Manual

    Energy Technology Data Exchange (ETDEWEB)

    2007-11-01

    This user manual describes the function and use of the portable digital radiography and computed tomography (DRCT) scanner. The manual gives a general overview of x-ray imaging systems along with a description of the DRCT system. An inventory of the all the system components, organized by shipping container, is also included. In addition, detailed, step-by-step procedures are provided for all of the exercises necessary for a novice user to successfully collect digital radiographs and tomographic images of an object, including instructions on system assembly and detector calibration and system alignment. There is also a short section covering the limited system care and maintenance needs. Descriptions of the included software packages, the DRCT Digital Imager used for system operation, and the DRCT Image Processing Interface used for image viewing and tomographic data reconstruction are given in the appendixes. The appendixes also include a cheat sheet for more experienced users, a listing of known system problems and how to mitigate them, and an inventory check-off sheet suitable for copying and including with the machine for shipment purposes.

  9. Gradient computation for VTI acoustic wavefield tomography

    KAUST Repository

    Li, Vladimir

    2016-09-06

    Wavefield tomography can handle complex subsurface geology better than ray-based techniques and, ultimately, provide a higher resolution. Here, we implement forward and adjoint wavefield extrapolation for VTI (transversely isotropic with a vertical symmetry axis) media using a pseudospectral operator that employes a separable approximation of the P-wave dispersion relation. This operator is employed to derive the gradients of the differential semblance optimization (DSO) and modified stack-power objective functions. We also obtain the gradient expressions for the data-domain objective function, which can incorporate borehole information necessary for stable VTI velocity analysis. These gradients are compared to the ones obtained with a space-time finite-difference (FD) scheme for a system of coupled wave equations. Whereas the kernels computed with the two wave-equation operators are similar, the pseudospectral method is not hampered by the imprint of the shear-wave artifact. Numerical examples also show that the modified stack-power objective function produces cleaner gradients than the more conventional DSO operator.

  10. Perfusion computed tomography in renal cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    Chandan; J; Das; Usha; Thingujam; Ananya; Panda; Sanjay; Sharma; Arun; Kumar; Gupta

    2015-01-01

    Various imaging modalities are available for the diagnosis, staging and response evaluation of patients with renal cell carcinoma(RCC). While contrast enhanced computed tomography(CT) is used as the standard of imaging for size, morphological evaluation and response assessment in RCC, a new functional imaging technique like perfusion CT(p CT), goes down to the molecular level and provides new perspectives in imaging of RCC. p CT depicts regional tumor perfusion and vascular permeability which are indirect parameters of tumor angiogenesis and thereby provides vital information regarding tumor microenvironment. Also response evaluation using p CT may predate the size criteria used in Response Evaluation Criteria in Solid Tumors, as changes in the perfusion occurs earlier following tissue kinase inhibitors before any actual change in size. This may potentially help in predicting prognosis, better selection of therapy and more accurate and better response evaluation in patients with RCC. This article describes the techniques and role of p CT in staging and response assessment in patients with RCCs.

  11. REVIEW: X-ray computed tomography

    Science.gov (United States)

    Kalender, Willi A.

    2006-07-01

    X-ray computed tomography (CT), introduced into clinical practice in 1972, was the first of the modern slice-imaging modalities. To reconstruct images mathematically from measured data and to display and to archive them in digital form was a novelty then and is commonplace today. CT has shown a steady upward trend with respect to technology, performance and clinical use independent of predictions and expert assessments which forecast in the 1980s that it would be completely replaced by magnetic resonance imaging. CT not only survived but exhibited a true renaissance due to the introduction of spiral scanning which meant the transition from slice-by-slice imaging to true volume imaging. Complemented by the introduction of array detector technology in the 1990s, CT today allows imaging of whole organs or the whole body in 5 to 20 s with sub-millimetre isotropic resolution. This review of CT will proceed in chronological order focussing on technology, image quality and clinical applications. In its final part it will also briefly allude to novel uses of CT such as dual-source CT, C-arm flat-panel-detector CT and micro-CT. At present CT possibly exhibits a higher innovation rate than ever before. In consequence the topical and most recent developments will receive the greatest attention.

  12. Computer tomography-aided ventriculography and cisternography

    Energy Technology Data Exchange (ETDEWEB)

    Cernoch, Z.; Sercl, M.; Heger, L.; Parizek, J. (Karlova Univ., Hradec Kralove (Czechoslovakia). Lekarska Fakulta)

    1983-01-28

    Computer tomography was used in 42 patients for the exploration of ventricular and subarachnoidal spaces following intraventricular, lumbar or suboccipital injections of 3 to 5 ml Amipaque using the kind of manoeuvre to permit optimum filling of the region concerned. This type of CT ventriculo- or cisternography is a significant supplement to plain CT examination particularly because it supplies data on the causes of CSF passage blocks. Thus, in two female patients it proved possible to localize cysts in the 3rd ventricle, the density of which was no different from that of CSF. As regards benign stenoses of the aqueduct, it is likely to yield less information than conventional specific ventriculography. On the other hand, the technique gives perfect visualization of all possible communications between pathological intracranial cavities and the ventricular system. CT cisternography proved useful for the identification of small-size isodense growths in the region of the sella turcica, and brought convincing evidence of the causes of profuse liquorrhea by demonstrating the presence of nasal meningocele. It was also found helpful in the analysis of the craniocervical region, otherwise difficult to survey.

  13. Intraperitoneal tuberculous abscess: computed tomography features

    Institute of Scientific and Technical Information of China (English)

    Peng; Dong; Jing-Jing; Chen; Xi-Zhen; Wang; Ya-Qin; Wang

    2015-01-01

    AIM: To evaluate the computed tomography(CT) features of intraperitoneal tuberculous abscess(IPTA). METHODS: Eight patients with IPTA confirmed by pathology were analyzed retrospectively. The clinical symptoms, medical images, and surgical findings were evaluated. Involvement of the intestine, peritoneum, viscera, and lymph nodes was also assessed. RESULTS: All 8 patients had a history of abdominal discomfort for 1 to 6 mo. Physical examination revealed a palpable abdominal mass in 6 patients. Three patients had no evidence of pulmonary tuberculosis(TB). All IPTAs(11 abscesses) were seen as a multiseptated, peripherally enhanced, hypodense mass with enlarged, rim-enhanced lymph nodes. The largest abscess diameter ranged from 4.5 cm to 12.2 cm. CT showed 2 types of IPTA: Lymph node fusion and encapsulation. Of the 8 patients, one had liver tuberculosis and one had splenic and ovarian tuberculosis. Two cases showed involvement of the terminal ileum and ileocecal junction. Ascites were found in 4 cases. Three patients had peritonitis and mesenteritis. Three patients showed involvement of the omentum. Three patients had histological evidence of caseating granuloma, and 5 had histological evidence of acid-fast bacilli. CONCLUSION: CT is crucial in the detection and characterization of IPTA. Certain CT findings are necessary for correct diagnosis.

  14. A Detector for Proton Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Blazey, G.; et al.

    2013-12-06

    Radiation therapy is a widely recognized treatment for cancer. Energetic protons have distinct features that set them apart from photons and make them desirable for cancer therapy as well as medical imaging. The clinical interest in heavy ion therapy is due to the fact that ions deposit almost all of their energy in a sharp peak – the Bragg peak- at the very end of their path. Proton beams can be used to precisely localize a tumor and deliver an exact dose to the tumor with small doses to the surrounding tissue. Proton computed tomography (pCT) provides direct information on the location on the target tumor, and avoids position uncertainty caused by treatment planning based on imaging with X-ray CT. The pCT project goal is to measure and reconstruct the proton relative stopping power distribution directly in situ. To ensure the full advantage of cancer treatment with 200 MeV proton beams, pCT must be realized.

  15. Acute Calculous Cholecystitis Missed on Computed Tomography and Ultrasound but Diagnosed with Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Carina Mari Aparici

    2016-01-01

    Full Text Available We present a case of a 69-year-old patient who underwent ascending aortic aneurysm repair with aortic valve replacement. On postsurgical day 12, he developed leukocytosis and low-grade fevers. The chest computed tomography (CT showed a periaortic hematoma which represents a postsurgical change from aortic aneurysm repair, and a small pericardial effusion. The abdominal ultrasound showed cholelithiasis without any sign of cholecystitis. Finally, a fluorodeoxyglucose (FDG-positron emission tomography (PET/CT examination was ordered to find the cause of fever of unknown origin, and it showed increased FDG uptake in the gallbladder wall, with no uptake in the lumen. FDG-PET/CT can diagnose acute cholecystitis in patients with nonspecific clinical symptoms and laboratory results.

  16. Diffuse abnormalities of the trachea: computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Radiologia]. E-mail: edmarchiori@gmail.com; Pozes, Aline Serfaty [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Escola de Medicina. Dept. de Radiologia; Escuissato, Dante Luiz [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Radiologia; Irion, Klaus Loureiro [The Cardiothoracic Centre NHS Trust, Liverpool (United Kingdom); Araujo Neto, Cesar de [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Dept. de Radiologia; Barillo, Jorge Luiz; Zanetti, Glaucia [Faculdade de Medicina de Petropolis (FMP), RJ (Brazil). Dept. de Cirurgia Clinica; Souza, Carolina Althoff [University of Ottawa, Ottawa, ON (Canada)

    2008-01-15

    The aim of this pictorial essay was to present the main computed tomography findings seen in diffuse diseases of the trachea. The diseases studied included amyloidosis, tracheobronchopathia osteochondroplastica, tracheobronchomegaly, laryngotracheobronchial papillomatosis, lymphoma, neurofibromatosis, relapsing polychondritis, Wegener's granulomatosis, tuberculosis, paracoccidioidomycosis, and tracheobronchomalacia. The most common computed tomography finding was thickening of the walls of the trachea, with or without nodules, parietal calcifications, or involvement of the posterior wall. Although computed tomography allows the detection and characterization of diseases of the central airways, and the correlation with clinical data reduces the diagnostic possibilities, bronchoscopy with biopsy remains the most useful procedure for the diagnosis of diffuse lesions of the trachea. (author)

  17. Abdominal alterations in disseminated paracoccidioidomycosis: computed tomography findings*

    Science.gov (United States)

    Vermelho, Marli Batista Fernandes; Correia, Ademir Silva; Michailowsky, Tânia Cibele de Almeida; Suzart, Elizete Kazumi Kuniyoshi; Ibanês, Aline Santos; Almeida, Lanamar Aparecida; Khoury, Zarifa; Barba, Mário Flores

    2015-01-01

    Objective To evaluate the incidence and spectrum of abdominal computed tomography imaging findings in patients with paracoccidioidomycosis. Materials and Methods Retrospective analysis of abdominal computed tomography images of 26 patients with disseminated paracoccidioidomycosis. Results Abnormal abdominal tomographic findings were observed in 18 patients (69.2%), while no significant finding was observed in the other 8 (30.8%) patients. Conclusion Computed tomography has demonstrated to play a relevant role in the screening and detection of abdominal abnormalities in patients with disseminated paracoccidioidomycosis. PMID:25987748

  18. Abdominal alterations in disseminated paracoccidioidomycosis: computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Vermelho, Marli Batista Fernandes; Correia, Ademir Silva; Michailowsky, Tania Cibele de Almeida; Suzart, Elizete Kazumi Kuniyoshi; Ibanes, Aline Santos; Almeida, Lanamar Aparecida; Khoury, Zarifa; Barba, Mario Flores, E-mail: marlivermelho@globo.com [Instituto de Infectologia Emilio Ribas (IIER), Sao Paulo, SP (Brazil)

    2015-03-15

    Objective: to evaluate the incidence and spectrum of abdominal computed tomography imaging findings in patients with paracoccidioidomycosis. Materials and methods: retrospective analysis of abdominal computed tomography images of 26 patients with disseminated paracoccidioidomycosis. Results: abnormal abdominal tomographic findings were observed in 18 patients (69.2%), while no significant finding was observed in the other 8 (30.8%) patients. Conclusion: computed tomography has demonstrated to play a relevant role in the screening and detection of abdominal abnormalities in patients with disseminated paracoccidioidomycosis. (author)

  19. Calcium score of small coronary calcifications on multidetector computed tomography

    DEFF Research Database (Denmark)

    Groen, J M; Kofoed, K F; Zacho, M;

    2013-01-01

    Multi detector computed tomography (MDCT) underestimates the coronary calcium score as compared to electron beam tomography (EBT). Therefore clinical risk stratification based on MDCT calcium scoring may be inaccurate. The aim of this study was to assess the feasibility of a new phantom which ena...

  20. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle W

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...

  1. Assessment of coronary artery bypass graft patency by multidetector computed tomography and electron-beam tomography

    NARCIS (Netherlands)

    Piers, LH; Dorgelo, J; Tio, RA; Jessurun, GAJ; Oudkerk, M; Zijlstra, F

    2005-01-01

    This case report describes the use of retrospectively ECG-gated 16-slice multidetector computed tomography (MDCT) and electron-beam tomography (EBT) for assessing bypass graft patency in two patients with recurrent angina after coronary artery bypass graft surgery. The results of each tomographic mo

  2. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle W

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...

  3. Positron emission tomography/computed tomography for optimized colon cancer staging and follow up

    DEFF Research Database (Denmark)

    Engelmann, Bodil Elisabeth; Loft, Annika; Kjær, Andreas;

    2014-01-01

    OBJECTIVES: Optimal management of colon cancer (CC) requires detailed assessment of extent of disease. This study prospectively investigates the diagnostic accuracy of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (PET/CT) for staging and detection of recurrence...

  4. The Use of GPUs for Solving the Computed Tomography Problem

    Directory of Open Access Journals (Sweden)

    A.E. Kovtanyuk

    2014-07-01

    Full Text Available Computed tomography (CT is a widespread method used to study the internal structure of objects. The method has applications in medicine, industry and other fields of human activity. In particular, Electronic Imaging, as a species CT, can be used to restore the structure of nanosized objects. Accurate and rapid results are in high demand in modern science. However, there are computational limitations that bound the possible usefulness of CT. On the other hand, the introduction of high-performance calculations using Graphics Processing Units (GPUs provides improving quality and performance of computed tomography investigations. Moreover, parallel computing with GPUs gives significantly higher computation speeds when compared with (Central Processing Units CPUs, because of architectural advantages of the former. In this paper a computed tomography method of recovering the image using parallel computations powered by NVIDIA CUDA technology is considered. The implementation of this approach significantly reduces the required time for solving the CT problem.

  5. Single-photon emission computed tomography/computed tomography in brain tumors.

    Science.gov (United States)

    Schillaci, Orazio; Filippi, Luca; Manni, Carlo; Santoni, Riccardo

    2007-01-01

    Anatomic imaging procedures (computed tomography [CT] and magnetic resonance imaging [MRI]) have become essential tools for brain tumor assessment. Functional images (positron emission tomography [PET] and single-photon emission computed tomography [SPECT]) can provide additional information useful during the diagnostic workup to determine the degree of malignancy and as a substitute or guide for biopsy. After surgery and/or radiotherapy, nuclear medicine examinations are essential to assess persistence of tumor, to differentiate recurrence from radiation necrosis and gliosis, and to monitor the disease. The combination of functional images with anatomic ones is of the utmost importance for a full evaluation of these patients, which can be obtained by means of imaging fusion. Despite the fast-growing diffusion of PET, in most cases of brain tumors, SPECT studies are adequate and provide results that parallel those obtained with PET. The main limitation of SPECT imaging with brain tumor-seeking radiopharmaceuticals is the lack of precise anatomic details; this drawback is overcome by the fusion with morphological studies that provide an anatomic map to scintigraphic data. In the past, software-based fusion of independently performed SPECT and CT or MRI demonstrated usefulness for brain tumor assessment, but this process is often time consuming and not practical for everyday nuclear medicine studies. The recent development of dual-modality integrated imaging systems, which allow the acquisition of SPECT and CT images in the same scanning session, and their co-registration by means of the hardware, has facilitated this process. In SPECT studies of brain tumors with various radiopharmaceuticals, fused images are helpful in providing the precise localization of neoplastic lesions, and in excluding the disease in sites of physiologic tracer uptake. This information is useful for optimizing diagnosis, therapy monitoring, and radiotherapy treatment planning, with a

  6. Computed tomography (CT) and diastematomyelia's diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Santos, M.B. dos; Luca, V. de; Ferreira, M.A.S. (Rio de Janeiro Univ. (Brazil). Faculdade de Medicina); Barros, A.P. de (Rio de Janeiro Univ. (Brazil). Hospital Universitario)

    After a case of diastematomyelia observed at the University Hospital (Federal University of Rio de Janeiro, Brazil) a review is done of the pertaining literature, and the contribution of the computed tomography for the diagnosis of this disease is emphasized.

  7. Time Domain Terahertz Axial Computed Tomography Non Destructive Evaluation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to demonstrate key elements of feasibility for a high speed automated time domain terahertz computed axial tomography (TD-THz CT) non destructive...

  8. Perfusion computed tomography to assist decision making for stroke thrombolysis

    Science.gov (United States)

    Levi, Christopher; Krishnamurthy, Venkatesh; McElduff, Patrick; Miteff, Ferdi; Spratt, Neil J.; Bateman, Grant; Donnan, Geoffrey; Davis, Stephen; Parsons, Mark

    2015-01-01

    The use of perfusion imaging to guide selection of patients for stroke thrombolysis remains controversial because of lack of supportive phase three clinical trial evidence. We aimed to measure the outcomes for patients treated with intravenous recombinant tissue plasminogen activator (rtPA) at a comprehensive stroke care facility where perfusion computed tomography was routinely used for thrombolysis eligibility decision assistance. Our overall hypothesis was that patients with ‘target’ mismatch on perfusion computed tomography would have improved outcomes with rtPA. This was a prospective cohort study of consecutive ischaemic stroke patients who fulfilled standard clinical/non-contrast computed tomography eligibility criteria for treatment with intravenous rtPA, but for whom perfusion computed tomography was used to guide the final treatment decision. The ‘real-time’ perfusion computed tomography assessments were qualitative; a large perfusion computed tomography ischaemic core, or lack of significant perfusion lesion-core mismatch were considered relative exclusion criteria for thrombolysis. Specific volumetric perfusion computed tomography criteria were not used for the treatment decision. The primary analysis compared 3-month modified Rankin Scale in treated versus untreated patients after ‘off-line’ (post-treatment) quantitative volumetric perfusion computed tomography eligibility assessment based on presence or absence of ‘target’ perfusion lesion-core mismatch (mismatch ratio >1.8 and volume >15 ml, core perfusion computed tomography-selected rtPA-treated patients to an Australian historical cohort of non-contrast computed tomography-selected rtPA-treated patients. Of 635 patients with acute ischaemic stroke eligible for rtPA by standard criteria, thrombolysis was given to 366 patients, with 269 excluded based on visual real-time perfusion computed tomography assessment. After off-line quantitative perfusion computed tomography classification

  9. Time Domain Terahertz Axial Computed Tomography Non Destructive Evaluation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase 2 project, we propose to develop, construct, and deliver to NASA a computed axial tomography time-domain terahertz (CT TD-THz) non destructive...

  10. Computed tomography and childhood seizure disorder in Ibadan ...

    African Journals Online (AJOL)

    Computed tomography and childhood seizure disorder in Ibadan. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... the subjects who had cranial scans done in five years were children with seizures disorders.

  11. Optimisation of post mortem cardiac computed tomography compared to optical coherence tomography and histopathology - Technical note

    DEFF Research Database (Denmark)

    Precht, Helle; Leth, Peter Mygind; Thygesen, Jesper

    2014-01-01

    Introduction: Coronary atherosclerosis is a leading cause of mortality. New technological developments in computed tomography (CT), including dual energy, iterative reconstructions and high definition scanning, could significantly improve the non-invasive identification of atherosclerosis plaques...

  12. Cone beam computed tomography in Endodontics - a review.

    Science.gov (United States)

    Patel, S; Durack, C; Abella, F; Shemesh, H; Roig, M; Lemberg, K

    2015-01-01

    Cone beam computed tomography (CBCT) produces undistorted three-dimensional information of the maxillofacial skeleton, including the teeth and their surrounding tissues with a lower effective radiation dose than computed tomography. The aim of this paper is to: (i) review the current literature on the applications and limitations of CBCT; (ii) make recommendations for the use of CBCT in Endodontics; (iii) highlight areas of further research of CBCT in Endodontics. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  13. A Clinical Evaluation of Cone Beam Computed Tomography

    Science.gov (United States)

    2013-07-31

    multidetector computed tomography and cone beam computed tomography in the assessment of dental implant site dimensions. Dentomaxillofac Radiol 2011;40:67-75...submitted to the Faculty of the Endodontics Graduate Program Naval Postgraduate Dental School Uniformed Services University of the Health Sciences...in partial fulfillment of the requirements of the degree of Master of Science in Oral Biology June 2013 Naval Postgraduate Dental

  14. Computed tomography of the mediastinum in myasthenia gravis

    Energy Technology Data Exchange (ETDEWEB)

    Guertler, K.F.; Janzen, R.W.C.; Hagemann, J.; Otto, H.F.

    1982-01-01

    Computed tomography of the mediastinum was performed in 45 patients with myasthenia gravis. Surgery was carried out in fourteen. Amongst these, there were four thymomas, one thymolipoma, eight thymic hyperplasias and one normal thymus gland. A further patient, who did not have surgery, probably also had a thymic tumour. The normal thymus and thymic hyperplasia cannot be distinguished on computed tomography. Differentiation of small thymomas from normal thymus is not always possible. Invasion by thymomas can only be appreciated with large tumours.

  15. Comparison between conventional tomography and computer tomography in diseases of the sacroiliac joints. Vergleich von konventioneller Tomographie und Computertomographie bei Erkrankungen der Sakroiliakalgelenke

    Energy Technology Data Exchange (ETDEWEB)

    Moritz, J.D.; Ganter, H.; Winter, C. (Bundeswehrkrankenhaus, Giessen (Germany, F.R.). Roentgenabteilung Evangelisches Krankenhaus, Giessen (Germany, F.R.). Roentgenabteilung)

    1990-10-01

    16 patients with diseases of the sacroiliac joints were examined both with computer tomography and with conventional tomography. Both techniques were characterized by a high sensitivity. Computer tomography was superior in exactly delineating the extent of the pathologic changes. In conventional tomography the joint surface was more blurred, erosions were larger, and signs of ankylosis were more expanded, so that the joints seemed to be more altered in 8 cases than demonstrated by computer tomography. Very accurate changes like subchondral cysts were recognized only in the computer tomograms. In all cases in which anteroposterior radiographs revealed no clear result, the authors recommend to additionally employ computer tomography. (orig.).

  16. Computed tomography of the orbital tumors

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jai Korl; Lee, Hwang Bok; Kang, Eun Young; Seol, Hae Young; Suh, Won Hyuck [College of Medicine, Korea University, Seoul (Korea, Republic of); Ahn, Byeong Yeob [Han Mi Hospital, Seoul (Korea, Republic of)

    1987-04-15

    The development of computed tomography (CT) provided a noninvasive safe technique for imaging the orbit in any plane exquisitely demonstrating its normal anatomy as well as its pathologic process. The orbit is an ideal structure to be examined by CT because of large difference of absorption values between the intraorbital fat, muscle, optic nerve and vessels. In this study, the authors reviewed CT findings of 66 pathologically proven orbital tumors and tumorous conditions among the total of 98 cases who had taken orbital CT scan because if exophthalmos, ocular pain, diplopia and other ophthalmologic symptoms suggesting orbital masses during the period of 3 years. For the analysis of characteristic CT findings of the orbital lesions, all lesions are divided into 4 groups according to the site of origin, i.e., tumors arising in the eyeball (group 1); from intraconal space (group 2); from extraconal space (group 3); and from extraorbital regions (group 4). The results are as follows; 1.Extra tumor detection and localization was possible in 63 cases. Thus the detection rate was 95% with CT scan. 2.Among 36 males and 30 females, their age ranged from 10 months to 72 years. 3.Intraocular tumors (group 1) were 10 cases. Retinoblastoma occurred wholly in the young children under 5 years and combined with calcification in 57%. Choroidal melanoma occurred wholly in adults. 4.Intraconal tumors (group 2) were 9 cases. Vascular tumors (7 cases) were the most frequent and well enhancing mass. 5.The tumors arising in the extraconal region (group 3) were pseudotumor (12 cases), lymphoma (3 cases), dermoid cyst (4 cases), metastasis (2 cases), adenoid cystic carcinoma (1 case) and teratoma (1 case). A case of lymphoma demonstrating retrobulbar ill defined mass with scleral l thickening could not be differentiated from the pseudotumor which showing similar finding. 6.The lesions arising from extraorbital region (group 4) were PNS cancer (9 cases), mucocele (3 cases), lid cancer (4

  17. Incidence of blunt craniocervical artery injuries: use of whole-body computed tomography trauma imaging with adapted computed tomography angiography.

    Science.gov (United States)

    Fleck, Steffen K; Langner, Soenke; Baldauf, Joerg; Kirsch, Michael; Kohlmann, Thomas; Schroeder, Henry W S

    2011-09-01

    The incidence of traumatic craniocervical artery dissection varies in published trauma series. To determine the frequency of traumatic craniocervical artery injury in polytrauma patients by using standardized whole-body trauma computed tomography with adapted computed tomography angiography of the craniocervical vessels. A total of 718 consecutive patients requiring whole-body trauma computed tomography (16-row multislice) because of the mechanism of their injury patterns and an Injury Severity Scale score greater than 16 were analyzed prospectively. After a cranial scan, computed tomography angiography of the craniocervical vessels with 40 mL of iodinated contrast agent was performed using bolus tracking. The overall incidence of blunt carotid and vertebral injuries (BCVIs) in the screened population was 1.7%. BCVIs were observed in 27.3% of patients with detected isolated cervical spine injuries and in 3.9% of patients with isolated cranial fractures with or without intracranial hemorrhage, whereas 5.3% of patients with combined cervical and cranial lesions were associated with BCVIs. In addition, 0.4% of BCVIs occurred in patients without evidence of head or neck trauma. Whole-body trauma computed tomography with an adapted scanning protocol for the craniocervical vessels is a fast, safe, and feasible method for detecting vascular injuries. It allows prompt further treatment if necessary. Computed tomography angiography could be a part of a broad screening protocol for craniocervical vessels in documented injuries of the head and neck and in trauma mechanisms influencing the craniocervical region as well.

  18. Foveola pharyngea - demonstration in conventional tomography and computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Fiegler, W.; Stolle, E.

    1980-08-01

    The foveola pharyngea is a cavity on the underside of the clivus, located before the tuberculum pharyngeum and, as a larger pit it was detectable in approx. 1% overall in approx. 4% of the personally examined X-rays (11/284) and computed tomograms (6/154) of the skull base. The canalis basilaris medianus inferior and canalis basilaris medianus bifurcatus almost always empties into one of the three forms of the foveola pharyngea (foveola pharyngea infundibuliformis posterior). The differential diagnosis to canalis basilaris medianus, canalis craniopharyngeus, sutura sphenooccipitalis and bone destruction is discussed.

  19. Development of a proton Computed Tomography Detector System

    CERN Document Server

    Naimuddin, Md; Blazey, G; Boi, S; Dyshkant, A; Erdelyi, B; Hedin, D; Johnson, E; Krider, J; Rukalin, V; Uzunyan, S A; Zutshi, V; Fordt, R; Sellberg, G; Rauch, J E; Roman, M; Rubinov, P; Wilson, P

    2015-01-01

    Computer tomography is one of the most promising new methods to image abnormal tissues inside the human body. Tomography is also used to position the patient accurately before radiation therapy. Hadron therapy for treating cancer has become one of the most advantageous and safe options. In order to fully utilize the advantages of hadron therapy, there is a necessity of performing radiography with hadrons as well. In this paper we present the development of a proton computed tomography system. Our second-generation proton tomography system consists of two upstream and two downstream trackers made up of fibers as active material and a range detector consisting of plastic scintillators. We present details of the detector system, readout electronics, and data acquisition system as well as the commissioning of the entire system. We also present preliminary results from the test beam of the range detector.

  20. Development of a proton Computed Tomography Detector System

    Energy Technology Data Exchange (ETDEWEB)

    Naimuddin, Md. [Delhi U.; Coutrakon, G. [Northern Illinois U.; Blazey, G. [Northern Illinois U.; Boi, S. [Northern Illinois U.; Dyshkant, A. [Northern Illinois U.; Erdelyi, B. [Northern Illinois U.; Hedin, D. [Northern Illinois U.; Johnson, E. [Northern Illinois U.; Krider, J. [Northern Illinois U.; Rukalin, V. [Northern Illinois U.; Uzunyan, S. A. [Northern Illinois U.; Zutshi, V. [Northern Illinois U.; Fordt, R. [Fermilab; Sellberg, G. [Fermilab; Rauch, J. E. [Fermilab; Roman, M. [Fermilab; Rubinov, P. [Fermilab; Wilson, P. [Fermilab

    2016-02-04

    Computer tomography is one of the most promising new methods to image abnormal tissues inside the human body. Tomography is also used to position the patient accurately before radiation therapy. Hadron therapy for treating cancer has become one of the most advantegeous and safe options. In order to fully utilize the advantages of hadron therapy, there is a necessity of performing radiography with hadrons as well. In this paper we present the development of a proton computed tomography system. Our second-generation proton tomography system consists of two upstream and two downstream trackers made up of fibers as active material and a range detector consisting of plastic scintillators. We present details of the detector system, readout electronics, and data acquisition system as well as the commissioning of the entire system. We also present preliminary results from the test beam of the range detector.

  1. Development of a proton Computed Tomography detector system

    Science.gov (United States)

    Naimuddin, Md.; Coutrakon, G.; Blazey, G.; Boi, S.; Dyshkant, A.; Erdelyi, B.; Hedin, D.; Johnson, E.; Krider, J.; Rukalin, V.; Uzunyan, S. A.; Zutshi, V.; Fordt, R.; Sellberg, G.; Rauch, J. E.; Roman, M.; Rubinov, P.; Wilson, P.

    2016-02-01

    Computer tomography is one of the most promising new methods to image abnormal tissues inside the human body. Tomography is also used to position the patient accurately before radiation therapy. Hadron therapy for treating cancer has become one of the most advantegeous and safe options. In order to fully utilize the advantages of hadron therapy, there is a necessity of performing radiography with hadrons as well. In this paper we present the development of a proton computed tomography system. Our second-generation proton tomography system consists of two upstream and two downstream trackers made up of fibers as active material and a range detector consisting of plastic scintillators. We present details of the detector system, readout electronics, and data acquisition system as well as the commissioning of the entire system. We also present preliminary results from the test beam of the range detector.

  2. Evaluating iterative reconstruction performance in computed tomography.

    Science.gov (United States)

    Chen, Baiyu; Ramirez Giraldo, Juan Carlos; Solomon, Justin; Samei, Ehsan

    2014-12-01

    Iterative reconstruction (IR) offers notable advantages in computed tomography (CT). However, its performance characterization is complicated by its potentially nonlinear behavior, impacting performance in terms of specific tasks. This study aimed to evaluate the performance of IR with both task-specific and task-generic strategies. The performance of IR in CT was mathematically assessed with an observer model that predicted the detection accuracy in terms of the detectability index (d'). d' was calculated based on the properties of the image noise and resolution, the observer, and the detection task. The characterizations of image noise and resolution were extended to accommodate the nonlinearity of IR. A library of tasks was mathematically modeled at a range of sizes (radius 1-4 mm), contrast levels (10-100 HU), and edge profiles (sharp and soft). Unique d' values were calculated for each task with respect to five radiation exposure levels (volume CT dose index, CTDIvol: 3.4-64.8 mGy) and four reconstruction algorithms (filtered backprojection reconstruction, FBP; iterative reconstruction in imaging space, IRIS; and sinogram affirmed iterative reconstruction with strengths of 3 and 5, SAFIRE3 and SAFIRE5; all provided by Siemens Healthcare, Forchheim, Germany). The d' values were translated into the areas under the receiver operating characteristic curve (AUC) to represent human observer performance. For each task and reconstruction algorithm, a threshold dose was derived as the minimum dose required to achieve a threshold AUC of 0.9. A task-specific dose reduction potential of IR was calculated as the difference between the threshold doses for IR and FBP. A task-generic comparison was further made between IR and FBP in terms of the percent of all tasks yielding an AUC higher than the threshold. IR required less dose than FBP to achieve the threshold AUC. In general, SAFIRE5 showed the most significant dose reduction potentials (11-54 mGy, 77%-84%), followed by

  3. Lens dosimetry during examination of the sella turcica: comparison between conventional tomography and computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Louis, O.; Bette, L.; Noseda, A.

    1986-01-01

    Lens irradiation measurements were performed with thermo-luminescent lithium fluoride dosimeters during tomographic examinations of the sella turcica, simulated on a phantom head. Lens dosimetry during linear or hypocycloidal conventional tomography was compared with that during computed tomography (CT). Results showed that CT involved much lower radiation exposure to the lens than did conventional tomography and that the major part of the irradiation delivered by CT was related to axial scanning. Therefore, the major finding was that lens irradiation during CT of the sella can be kept at a particularly low level (< 1 m Gy/8 sections) when only coronal scanning is performed.

  4. Acute mediastinitis: multidetector computed tomography findings following cardiac surgery

    Energy Technology Data Exchange (ETDEWEB)

    Macedo, Clarissa Aguiar de [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina. Instituto do Coracao (InCor)]. E-mail: clarissaaguiarm@yahoo.com.br; Baena, Marcos Eduardo da Silva [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Ultrasonography; Uezumi, Kiyomi Kato [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Computed Tomography; Castro, Claudio Campi de [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Magnetic Resonance Imaging; Lucarelli, Claudio Luiz [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Center of Diagnosis; Cerri, Giovanni Guido [Universidade de Sao Paulo (USP), SP (Brazil). School of Medicine. Dept. of Radiology

    2008-07-15

    Postoperative mediastinitis is defined as an infection of the organs and tissues in the mediastinal space, with an incidence ranging between 0.4% and 5% of cases. This disease severity varies from infection of superficial tissues in the chest wall to fulminant mediastinitis with sternal involvement. Diagnostic criterion for postoperative detection of acute mediastinitis at computed tomography is the presence of fluid collections and gas in the mediastinal space, which might or might not be associated with peristernal abnormalities such as edema of soft tissues, separation of sternal segments with marginal bone resorption, sclerosis and osteomyelitis. Other associated findings include lymphadenomegaly, pulmonary consolidation and pleural/ pericardial effusion. Some of these findings, such as mediastinal gas and small fluid collections can be typically found in the absence of infection, early in the period following thoracic surgery where the effectiveness of computed tomography is limited. After approximately two weeks, computed tomography achieves almost 100% sensitivity and specificity. Patients with clinical suspicion of mediastinitis should be submitted to computed tomography for investigating the presence of fluid collections to identify the extent and nature of the disease. Multidetector computed tomography allows 3D images reconstruction, contributing particularly to the evaluation of the sternum. (author)

  5. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle Westergren;

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...... study investigates the positive (PPV) and negative predictive value (NPV) of PET-CT in stage I disease and the clinical impact of the scan results in all disease stages....

  6. Pigmented villonodular synovitis mimics metastases on fluorine 18 fluorodeoxyglucose position emission tomography-computed tomography.

    Science.gov (United States)

    Elumogo, Comfort O; Kochenderfer, James N; Civelek, A Cahid; Bluemke, David A

    2016-04-01

    Pigmented villonodular synovitis (PVNS) is a benign joint disease best characterized on magnetic resonance imaging (MRI). The role of fluorine 18 fluorodeoxyglucose ((18)F-FDG) position emission tomography-computed tomography (PET-CT) in the diagnosis or characterization remains unclear. PVNS displays as a focal FDG avid lesion, which can masquerade as a metastatic lesion, on PET-CET. We present a case of PVNS found on surveillance imaging of a lymphoma patient.

  7. Optimisation of post mortem cardiac computed tomography compared to optical coherence tomography and histopathology - Technical note

    DEFF Research Database (Denmark)

    Precht, Helle; Leth, Peter Mygind; Thygesen, Jesper

    2014-01-01

    Introduction: Coronary atherosclerosis is a leading cause of mortality. New technological developments in computed tomography (CT), including dual energy, iterative reconstructions and high definition scanning, could significantly improve the non-invasive identification of atherosclerosis plaques....... Here, a new method for optimising cardiac coronary CT with optical coherence tomography (OCT) and histopathology is presented. Materials and methods: Twenty human hearts obtained from autopsies were used. A contrast agent that solidifies after cooling was injected into the coronary arteries. CT...

  8. Multifocal sparganosis mimicking lymphoma involvement: Multimodal imaging findings of ultrasonography, CT, MRI, and position emission tomography-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Heo, So Young; Park, Ji Yeon; Park, Noh Hyuck; Park, Chan Sub; Kim, Tae Jung [Myongji Hospital, Seonam University College of Medicine, Goyang (Korea, Republic of); Yi, Seong Yoon [Dev. of Hematology-Omcology, Dept. of Internal Medicine, Inje University Ilsan Paik Hospital, Goyang (Korea, Republic of); Jun, Hyun Jung [Dev. of Hematology-Omcology, Dept. of Internal Medicine, Seoul Medical Center, Seoul (Korea, Republic of)

    2016-01-15

    Sparganosis is a rare parasitic disease caused by the migrating plerocercoid larva of Spirometra species tapeworms. The most frequent clinical manifestation is a subcutaneous nodule resembling a neoplasm. In this study, we presented multimodal findings of ultrasonography, computed tomography, magnetic resonance imaging, positron emission tomography-computed tomography and follow-up imagings on multifocal sparganosis, mimicking lymphoma involvement in a patient with lymphoma.

  9. Shielding Calculations for Positron Emission Tomography - Computed Tomography Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Baasandorj, Khashbayar [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Yang, Jeongseon [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    Integrated PET-CT has been shown to be more accurate for lesion localization and characterization than PET or CT alone, and the results obtained from PET and CT separately and interpreted side by side or following software based fusion of the PET and CT datasets. At the same time, PET-CT scans can result in high patient and staff doses; therefore, careful site planning and shielding of this imaging modality have become challenging issues in the field. In Mongolia, the introduction of PET-CT facilities is currently being considered in many hospitals. Thus, additional regulatory legislation for nuclear and radiation applications is necessary, for example, in regulating licensee processes and ensuring radiation safety during the operations. This paper aims to determine appropriate PET-CT shielding designs using numerical formulas and computer code. Since presently there are no PET-CT facilities in Mongolia, contact was made with radiological staff at the Nuclear Medicine Center of the National Cancer Center of Mongolia (NCCM) to get information about facilities where the introduction of PET-CT is being considered. Well-designed facilities do not require additional shielding, which should help cut down overall costs related to PET-CT installation. According to the results of this study, building barrier thicknesses of the NCCM building is not sufficient to keep radiation dose within the limits.

  10. Evaluation of myocardial ischemia by multiple detector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Fabio Vieira, E-mail: rccury@me.com [Hospital do Coracao (HCor), Sao Paulo, SP (Brazil); Cury, Roberto Caldeira [Hospital Samaritano, Sao Paulo, SP (Brazil)

    2015-01-15

    For years, cardiovascular diseases have been the leading cause of death worldwide, bringing on important social and economic consequences. Given this scenario, the search for a method capable of diagnosing coronary artery diseases in an early and accurate way is increasingly higher. The coronary computed tomography angiogram is already widely established for the stratification of coronary artery diseases, and, more recently, the computed tomography myocardial perfusion imaging has been providing relevant information by correlating ischemia and the coronary anatomy. The objective of this review is to describe the evaluation of myocardial ischemia by multiple detector computed tomography. This study will resort to controlled clinical trials that show the possibility of a single method to identify the atherosclerotic load, presence of coronary artery luminal narrowing and possible myocardial ischemia, by means of a fast, practical and reliable method validated by a multicenter study. (author)

  11. Utility of the computed tomography indices on cone beam computed tomography images in the diagnosis of osteoporosis in women

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Kwang Joon; Kim, Kyung A [School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of)

    2011-09-15

    This study evaluated the potential use of the computed tomography indices (CTI) on cone beam CT (CBCT) images for an assessment of the bone mineral density (BMD) in postmenopausal osteoporotic women. Twenty-one postmenopausal osteoporotic women and 21 postmenopausal healthy women were enrolled as the subjects. The BMD of the lumbar vertebrae and femur were calculated by dual energy X-ray absorptiometry (DXA) using a DXA scanner. The CBCT images were obtained from the unilateral mental foramen region using a PSR-9000N Dental CT system. The axial, sagittal, and coronal images were reconstructed from the block images using OnDemend3D. The new term 'CTI' on CBCT images was proposed. The relationship between the CT measurements and BMDs were assessed and the intra-observer agreement was determined. There were significant differences between the normal and osteoporotic groups in the computed tomography mandibular index superior (CTI(S)), computed tomography mandibular index inferior (CTI(I)), and computed tomography cortical index (CTCI). On the other hand, there was no difference between the groups in the computed tomography mental index (CTMI: inferior cortical width). CTI(S), CTI(I), and CTCI on the CBCT images can be used to assess the osteoporotic women.

  12. Computed tomography of sellar and parasellar lesions

    Energy Technology Data Exchange (ETDEWEB)

    Hatano, Mitsunori; Aoki, Hideo (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1982-06-01

    Neuroradiological modalities, particularly CT, for sellar and parasellar lesions were reviewed. Although accurate preoperative diagnosis is sometimes difficult, CT diagnosed 83% as far as pituitary adenoma, craniopharyngioma and meningioma were concerned and demonstrated abnormal findings in 95% of parasellar tumors. At the authors' department, CT visualized abnormalities in all cases, with the exception of suprasellar arachnoid cyst, but a histological diagnosis was possible only in 84%. Since lesions including tumors cannot be completely denied even if CT shows normal images, findings by modalities such as plain craniography, cerebral tomography, cerebral angiography and cisternography should be judged comprehensively.

  13. Anaesthesia for magnetic resonance imaging/computed tomography.

    Science.gov (United States)

    Funk, W; Taeger, K

    2000-08-01

    The need for general anaesthesia for magnetic resonance imaging/computed tomography investigations can be reduced by the implementation of structured sedation programmes supervised by anaesthetists. Despite its side-effects, chloral hydrate is still the drug most widely used. Rectal thiopental or intravenous propofol are suggested anaesthetic agents for pre-school children and uncooperative or claustrophobic individuals. Spiral computed tomography scans and ultrafast magnetic resonance imaging shorten immobilization times further. However, functional magnetic resonance imaging and intervention techniques in neuroradiology depend on a motionless patient. A useful strategy for testing anaesthesia equipment has been outlined.

  14. Computed tomography and magnetic resonance imaging of the pericardium.

    Science.gov (United States)

    Olson, M C; Posniak, H V; McDonald, V; Wisniewski, R; Moncada, R

    1989-07-01

    Computed tomography is an established modality for the evaluation of the pericardium. It is used to evaluate complicated pericardial effusions, pericardial thickening, calcific pericarditis, pericardial cysts, postoperative changes and primary and metastatic neoplasms of the pericardium. Magnetic resonance imaging is being used with increasing frequency in the evaluation of pericardial disease. It offers advantages over computed tomography, including a potential for tissue characterization, absence of ionizing radiation or need for intravenous contrast medium, and the ability to scan in any plane. Disadvantages include greater cost, longer examination times and the inability to identify calcification positively.

  15. Investigation of a near-infrared-ray computed tomography scanner

    Science.gov (United States)

    Sato, Eiichi; Oda, Yasuyuki; Satoi, Yuichi; Yamaguchi, Satoshi; Ishii, Tomotaka; Hagiwara, Osahiko; Matsukiyo, Hiroshi; Watanabe, Manabu; Kusachi, Shinya

    2016-10-01

    In the near-infrared-ray computed tomography (NIR-CT) scanner, NIR rays are produced from a light-emitting diode (LED) and detected using an NIR phototransistor (PT). The wavelengths of the LED peak intensity and the PT high sensitivity in the data table are both 940 nm. The photocurrents flowing through the PTR are converted into voltages using an emitter-follower circuit, and the output voltages are sent to a personal computer through an analog-digital converter. The NIR projection curves for tomography are obtained by repeated linear scans and rotations of the object, and the scanning is conducted in both directions of its movement.

  16. Direct sagital computed tomography of the temporomandibular joint

    Energy Technology Data Exchange (ETDEWEB)

    Manzione, J.V. (Harvard Medical School, Boston, MA); Seltzer, S.E.; Katzberg, R.W.; Hammerschlag, S.B.; Chiango, B.F.

    1983-01-01

    Temporomandibular joint dysfunction is a common clinical problem that has been reported to affect 4%-28% of adults. Temporomandibular joint arthrography has shown that many of these patients have intraarticular abnormalities involving the meniscus. A noninvasive test that could demonstrate the meniscus as well as bony abnormalities of the joint would be an important advance. In an attempt to develop such a noninvasive test, we have performed direct sagittal computed tomography (CT) on cadaver temporomandibular joints and have correlated the images with anatomic sections. We are currently applying this technique clinically and report one representative example in which direct sagittal computed tomography of the temporomandibular joint accurately demonstrated an anteriorly displaced meniscus.

  17. Endocrine radionuclide scintigraphy with fusion single photon emission computed tomography/computed tomography

    Institute of Scientific and Technical Information of China (English)

    Ka-Kit Wong; Arpit Gandhi; Benjamin L Viglianti; Lorraine M Fig; Domenico Rubello; Milton D Gross

    2016-01-01

    AIM: To review the benefits of single photon emission computed tomography(SPECT)/computed tomography(CT) hybrid imaging for diagnosis of various endocrine disorders.METHODS: We performed MEDLINE and Pub Med searches using the terms: "SPECT/CT"; "functional anatomic mapping"; "transmission emission tomography"; "parathyroid adenoma"; "thyroid cancer"; "neuroendocrine tumor"; "adrenal"; "pheochromocytoma"; "paraganglioma"; in order to identify relevant articles published in English during the years 2003 to 2015. Reference lists from the articles were reviewed to identify additional pertinent articles. Retrieved manuscripts(case reports, reviews, meta-analyses and abstracts) concerning the application of SPECT/CT to endocrine imaging were analyzed to provide a descriptive synthesis of the utility of this technology.RESULTS: The emergence of hybrid SPECT/CT camera technology now allows simultaneous acquisition of combined multi-modality imaging, with seamless fusion of three-dimensional volume datasets. The usefulness of combining functional information to depict the biodistribution of radiotracers that map cellular processes of the endocrine system and tumors of endocrine origin, with anatomy derived from CT, has improved the diagnostic capability of scintigraphy for a range of disorders of endocrine gland function. The literature describes benefits of SPECT/CT for 99mTc-sestamibi parathyroid scintigraphy and 99mTc-pertechnetate thyroid scintigraphy, 123I- or 131I-radioiodine for staging of differentiated thyroid carcinoma, 111In- and 99mTclabeled somatostatin receptor analogues for detection of neuroendocrine tumors, 131I-norcholesterol(NP-59) scans for assessment of adrenal cortical hyperfunction, and 123I- or 131I-metaiodobenzylguanidine imaging for evaluation of pheochromocytoma and paraganglioma.CONCLUSION: SPECT/CT exploits the synergism between the functional information from radiopharmaceutical imaging and anatomy from CT, translating to

  18. Industrial Computed Tomography using Proximal Algorithm

    KAUST Repository

    Zang, Guangming

    2016-04-14

    In this thesis, we present ProxiSART, a flexible proximal framework for robust 3D cone beam tomographic reconstruction based on the Simultaneous Algebraic Reconstruction Technique (SART). We derive the proximal operator for the SART algorithm and use it for minimizing the data term in a proximal algorithm. We show the flexibility of the framework by plugging in different powerful regularizers, and show its robustness in achieving better reconstruction results in the presence of noise and using fewer projections. We compare our framework to state-of-the-art methods and existing popular software tomography reconstruction packages, on both synthetic and real datasets, and show superior reconstruction quality, especially from noisy data and a small number of projections.

  19. Computed tomography angiography and perfusion to assess coronary artery stenosis causing perfusion defects by single photon emission computed tomography

    DEFF Research Database (Denmark)

    Rochitte, Carlos E; George, Richard T; Chen, Marcus Y

    2014-01-01

    AIMS: To evaluate the diagnostic power of integrating the results of computed tomography angiography (CTA) and CT myocardial perfusion (CTP) to identify coronary artery disease (CAD) defined as a flow limiting coronary artery stenosis causing a perfusion defect by single photon emission computed...... tomography (SPECT). METHODS AND RESULTS: We conducted a multicentre study to evaluate the accuracy of integrated CTA-CTP for the identification of patients with flow-limiting CAD defined by ≥50% stenosis by invasive coronary angiography (ICA) with a corresponding perfusion deficit on stress single photon...

  20. 3D artefact for concurrent scale calibration in Computed Tomography

    DEFF Research Database (Denmark)

    Stolfi, Alessandro; De Chiffre, Leonardo

    2016-01-01

    A novel artefact for calibration of the scale in 3D X-ray Computed Tomography (CT) is presented. The artefact comprises a carbon fibre tubular structure on which a number of reference ruby spheres are glued. The artefact is positioned and scanned together with the workpiece inside the CT scanner ...

  1. Computer tomography in Caisson's disease

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, F.; Csobaly, S.

    1981-07-01

    Computer tomography was performed on 20 patients with the early stages of Caisson osteoarthropathy, as well as in other patients with chronic bone infarcts. From their results the authors have formed the opinion that CT is valuable, not only in the diagnosis of early cases, but that it can provide significant information concerning the osteopathy and bone infarcts.

  2. A Clinical Evaluation Of Cone Beam Computed Tomography

    Science.gov (United States)

    2016-06-01

    subject number. The principal investigator collated all data collection sheets and organized them into a spreadsheet for final analysis. Data...available cone-beam computed tomography machine . Am J 01ihod Dentofacial Orthop 2008; 134:573-82. 7. Moshfeghi M, Tavakoli MA, Hosseini ET, et al

  3. Geometrical metrology on silicone rubber by computed tomography

    DEFF Research Database (Denmark)

    Müller, Pavel; Pacurar, Ramona Alexandra; De Chiffre, Leonardo

    2011-01-01

    Computed tomography (CT) represents a suitable measuring technique for investigation of deformable materials, since no forces are developed on the part during scanning. As for any other measuring instruments, the traceability of the CT scanners needs to be assured. An investigation on geometrical...

  4. Traceability investigation in Computed Tomography using industry-inspired workpieces

    DEFF Research Database (Denmark)

    Kraemer, Alexandra; Stolfi, Alessandro; Schneider, Timm

    2017-01-01

    This paper concerns an investigation of the accuracy of Computed Tomography (CT) measurements using four industry-inspired workpieces. A total of 16 measurands were selected and calibrated using CMMs. CT measurements on industry-inspired workpieces were carried out using two CTs having different...

  5. Tracheo-oesophageal fistula diagnosed with multidetector computed tomography.

    LENUS (Irish Health Repository)

    Hodnett, Pa

    2009-04-01

    This case highlights important issues in investigation of patients with suspected tracheo-oesophageal fistula including the value of multidetector computed tomography, the importance of thorough imaging evaluation when high clinical suspicion of tracheo-oesophageal fistula exists and the value of close interaction between radiologists and intensive care physicians in the investigation of these patients.

  6. Computed Tomography Features of Spontaneously Perforated Pyometra: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Chan, K.S.; Tan, C.K.; Mak, C.W.; Chia, C.C.; Kuo, C.Y.; Yu, W.L. [Chi-Mei Medical Center, Tainan, Taiwan (China). Depts. of Intensive Care Medicine, Radiology, Obstetrics and Gynecology, and Surgery

    2006-03-15

    Spontaneous perforation of pyometra is an extremely rare emergent gynecologic disease. We report a 73-year-old woman with a spontaneously perforated pyometra presenting with acute abdomen in the emergency department. A dedicated computed tomography examination of the abdominal and pelvic regions revealed the diagnosis. The patient recovered well after surgical intervention and antibiotic treatment.

  7. Fractional flow reserve derived from coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Eftekhari, Ashkan; Min, James; Achenbach, Stephan

    2016-01-01

    AIMS: Fractional flow reserve (FFR) derived from coronary computed tomography (FFRCT) has high diagnostic performance in stable coronary artery disease (CAD). The diagnostic performance of FFRCT in patients with hypertension (HTN) and diabetes (DM), who are at risk of microvascular impairment, is...

  8. Computed tomography of the human developing anterior skull base

    NARCIS (Netherlands)

    J. van Loosen (J.); A.I.J. Klooswijk (A. I J); D. van Velzen (D.); C.D.A. Verwoerd (Carel)

    1990-01-01

    markdownabstractAbstract The ossification of the anterior skull base, especially the lamina cribrosa, has been studied by computed tomography and histopathology. Sixteen human fetuses, (referred to our laboratory for pathological examination after spontaneous abortion between 18 and 32 weeks of ge

  9. COMPUTED TOMOGRAPHY IN HYDATID CYST OF THE ORBIT

    Directory of Open Access Journals (Sweden)

    K. Abbassioun

    1982-07-01

    Full Text Available Two cases of hydatid cysts of the orbit causing unilateral exophthalmos are reported. Diagnosis were suspected by means of computed tomography (CT and confirmed at Operation. CT changes are described and its value in diagnosis of this lesion particularly in the endemic areas is stressed.

  10. Operator radiation exposure in cone-beam computed tomography guidance

    NARCIS (Netherlands)

    Braak, S.J.; Strijen Van, M. J L; Meijer, E.; Heesewijk Van, J. P M; Mali, W. P T M

    2016-01-01

    Objectives: Quantitative analysis of operator dose in cone-beam computed tomography guidance (CBCT-guidance) and the effect of protective shielding. Methods: Using a Rando phantom, a model was set-up to measure radiation dose for the operator hand, thyroid and gonad region. The effect of sterile rad

  11. Use of Computed Tomography Scans for Cochlear Implants

    OpenAIRE

    Whiting, Bruce R.; Holden, Timothy A.; Brunsden, Barry S.; Finley, Charles C.; Skinner, Margaret W.

    2007-01-01

    While 3-dimensional (3D) imaging by computed tomography has long been desirable for research and treatment of cochlear-implant patients, technical challenges have limited its wide application. Recent developments in scanner hardware and image processing techniques now allow image quality improvements that make clinical applications feasible. Validation experiments were performed to characterize a new methodology and its imaging performance.

  12. Computed tomography diagnosis of partial anomalous pulmonary venous drainage.

    Science.gov (United States)

    Posniak, H V; Dudiak, C M; Olson, M C

    1993-01-01

    A case of the rarely occurring partial anomalous pulmonary venous drainage of the right upper lobe into the azygos arch is presented. Computed tomography (CT) clearly demonstrated the abnormal vessel coursing through the right upper lobe and draining into the azygos arch.

  13. Coronary computed tomography - present status and future directions

    NARCIS (Netherlands)

    Apfaltrer, P.; Schoepf, U. J.; Vliegenthart, R.; Rowe, G. W.; Spears, J. R.; Fink, C.; Nance, J. W.

    2011-01-01

    The use of coronary computed tomography angiography (cCTA) is growing rapidly, in large part because of fast-paced technical innovations that have increased diagnostic accuracy while providing new opportunities for radiation dose reduction. cCTA using recent generation CT scanners has been repeatedl

  14. Coronary artery fly-through using electron beam computed tomography

    NARCIS (Netherlands)

    van Ooijen, P M; Oudkerk, M; van Geuns, R J; Rensing, B J; de Feyter, P J

    2000-01-01

    BACKGROUND: Virtual reality techniques have recently been introduced into clinical medicine. This study examines the possibility of coronary artery fly-through using a dataset obtained by noninvasive coronary angiography with contrast-enhanced electron-beam computed tomography. METHODS AND RESULTS:

  15. Cost-effectiveness of PET and PET/Computed Tomography

    DEFF Research Database (Denmark)

    Gerke, Oke; Hermansson, Ronnie; Hess, Søren

    2015-01-01

    measure by means of incremental cost-effectiveness ratios when considering the replacement of the standard regimen by a new diagnostic procedure. This article discusses economic assessments of PET and PET/computed tomography reported until mid-July 2014. Forty-seven studies on cancer and noncancer...

  16. Tolerance Verification of an Industrial Assembly using Computed Tomography

    DEFF Research Database (Denmark)

    Stolfi, Alessandro; De Chiffre, Leonardo; Regi, Francesco

    2016-01-01

    This paper reports on results of tolerance verification of a multi-material assembly by using Computed Tomography (CT). The workpiece comprises three parts which are made out of different materials. Five different measurands were inspected. The calculation of measurement uncertainties was attempt...

  17. Position emission tomography with or without computed tomography in the primary staging of Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Jakobsen, Annika Loft; Hansen, Mads;

    2006-01-01

    In order to receive the most appropriate therapy, patients with Hodgkin's lymphoma (HL) must be accurately stratified into different prognostic staging groups. Computed tomography (CT) plays a pivotal role in the conventional staging. The aim of the present study was to investigate the value...

  18. Global seismic tomography and modern parallel computers

    Directory of Open Access Journals (Sweden)

    A. Piersanti

    2006-06-01

    Full Text Available A fast technological progress is providing seismic tomographers with computers of rapidly increasing speed and RAM, that are not always properly taken advantage of. Large computers with both shared-memory and distributedmemory architectures have made it possible to approach the tomographic inverse problem more accurately. For example, resolution can be quantified from the resolution matrix rather than checkerboard tests; the covariance matrix can be calculated to evaluate the propagation of errors from data to model parameters; the L-curve method can be applied to determine a range of acceptable regularization schemes. We show how these exercises can be implemented efficiently on different hardware architectures.

  19. Inter laboratory comparison on Industrial Computed Tomography

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo; Larsen, Erik

    The ‘CIA-CT comparison - Inter laboratory comparison on industrial Computed Tomography” is organized by DTU Department of Mechanical Engineering within the Danish project “Centre for Industrial Application of CT scanning - CIA-CT”. The project is co-financed by the Danish Ministry of Science, Tec...

  20. Comparison of Computed Tomography Scout Based Reference Point Localization to Conventional Film and Axial Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Lan; Templeton, Alistair; Turian, Julius; Kirk, Michael; Zusag, Thomas; Chu, James C.H., E-mail: jchu@rush.edu

    2011-01-01

    Identification of source positions after implantation is an important step in brachytherapy planning. Reconstruction is traditionally performed from films taken by conventional simulators, but these are gradually being replaced in the clinic by computed tomography (CT) simulators. The present study explored the use of a scout image-based reconstruction algorithm that replaces the use of traditional film, while exhibiting low sensitivity to metal-induced artifacts that can appear in 3D CT methods. In addition, the accuracy of an in-house graphical software implementation of scout-based reconstruction was compared with seed location reconstructions for 2 phantoms by conventional simulator and CT measurements. One phantom was constructed using a planar fixed grid of 1.5-mm diameter ball bearings (BBs) with 40-mm spacing. The second was a Fletcher-Suit applicator embedded in Styrofoam (Dow Chemical Co., Midland, MI) with one 3.2-mm-diameter BB inserted into each of 6 surrounding holes. Conventional simulator, kilovoltage CT (kVCT), megavoltage CT, and scout-based methods were evaluated by their ability to calculate the distance between seeds (40 mm for the fixed grid, 30-120 mm in Fletcher-Suit). All methods were able to reconstruct the fixed grid distances with an average deviation of <1%. The worst single deviations (approximately 6%) were exhibited in the 2 volumetric CT methods. In the Fletcher-Suit phantom, the intermodality agreement was within approximately 3%, with the conventional sim measuring marginally larger distances, with kVCT the smallest. All of the established reconstruction methods exhibited similar abilities to detect the distances between BBs. The 3D CT-based methods, with lower axial resolution, showed more variation, particularly with the smaller BBs. With a software implementation, scout-based reconstruction is an appealing approach because it simplifies data acquisition over film-based reconstruction without requiring any specialized equipment

  1. Cranial computed tomography in psychiatry. Kraniale Computertomographie in der Psychiatrie

    Energy Technology Data Exchange (ETDEWEB)

    Falkai, P. (Rheinische Landes- und Hochschulklinik Duesseldorf, Psychiatrische Klinik der Heinrich-Heine-Universitaet (Germany)); Bogerts, B. (Rheinische Landes- und Hochschulklinik Duesseldorf, Psychiatrische Klinik der Heinrich-Heine-Universitaet (Germany))

    1993-08-13

    Computed tomography has gained importance as a diagnostic tool in psychiatry to exclude structural brain pathology, but has passed on its role in research to magnetic resonance tomography. It helps to distinguish between senile dementia of Alzheimer type and multi-infarct dementia. The enlargement of the ventricular system and cortical sulci is well established in schizophrenic and affective psychosis. Some alcohol addicts show a considerable degree of cerebral atrophy, only exceeded by demented patients, but this condition is potentially reversible. To screen psychiatric patients by CT is recommendable, as 2-10% of hospitalized psychiatric patients have structural brain disease. (orig.)

  2. Assessment of asthmatic inflammation using hybrid fluorescence molecular tomography-x-ray computed tomography

    Science.gov (United States)

    Ma, Xiaopeng; Prakash, Jaya; Ruscitti, Francesca; Glasl, Sarah; Stellari, Fabio Franco; Villetti, Gino; Ntziachristos, Vasilis

    2016-01-01

    Nuclear imaging plays a critical role in asthma research but is limited in its readings of biology due to the short-lived signals of radio-isotopes. We employed hybrid fluorescence molecular tomography (FMT) and x-ray computed tomography (XCT) for the assessment of asthmatic inflammation based on resolving cathepsin activity and matrix metalloproteinase activity in dust mite, ragweed, and Aspergillus species-challenged mice. The reconstructed multimodal fluorescence distribution showed good correspondence with ex vivo cryosection images and histological images, confirming FMT-XCT as an interesting alternative for asthma research.

  3. X-ray computed tomography of PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Pfrang, Andreas; Veyret, Damien; Tsotridis, Georgios [Commission of the European Communities, Petten (Netherlands). Joint Reseach Centre, Inst. for Energy; Janssen, Gaby [Energy Research Centre of the Netherlands ECN, Petten (Netherlands). Dept. of Hydrogen and Clean Fossil Fuels

    2010-07-01

    Proton exchange membrane (PEM) fuel cells were investigated by 3D x-ray computed tomography at a voxel size of 0.7 {mu}m. It is shown that this lab-based technique is not only suitable for the investigation of gas diffusion layers (GDL) as well as the investigation of membrane electrode assemblies (MEA), but also allows the calculation of macroscopic physical properties. The resolution of computed tomography is clearly sufficient to image the carbon fiber structure of gas diffusion layers in the as received GDLs as well as GDLs integrated into membrane electrode assemblies. It is also possible to visualize the catalyst layer within the MEA, which allows the investigation of layer thickness and structural defects on a larger scale than with conventional techniques. The macroscopic effective thermal conductivities of the gas diffusion layers were computed based on the 3D GDL structure reconstructed from tomography data to produce more reliable input data for fuel cell modeling. The computation was carried out by solving the energy equation considering a pure thermal conduction problem. The computations show - in agreement with the expectation and experimental data - that the through-plane thermal conductivities are lower than the in-plane thermal conductivities. (orig.)

  4. Coordinate Metrology by Traceable Computed Tomography

    DEFF Research Database (Denmark)

    Müller, Pavel

    metrology and coordinate metrology and is currently becoming more and more important measuring technique for dimensional measurements. This is mainly due to the fact that with CT, a complete three-dimensional model of the scanned part is in a relatively short time visualized using a computer...... is an important factor for decision making about manufactured parts. However, due to many influences in CT, estimation of the uncertainty is a challenge, also because standardized procedures and guidelines are not available yet. In this thesis, several methods for uncertainty estimation were applied in connection...

  5. Comparison of radiation absorbed dose in target organs in maxillofacial imaging with panoramic, conventional linear tomography, cone beam computed tomography and computed tomography

    Directory of Open Access Journals (Sweden)

    Panjnoush M.

    2009-12-01

    Full Text Available "nBackground and Aim: The objective of this study was to measure and compare the tissue absorbed dose in thyroid gland, salivary glands, eye and skin in maxillofacial imaging with panoramic, conventional linear tomography, cone beam computed tomography (CBCT and computed tomography (CT."nMaterials and Methods: Thermoluminescent dosimeters (TLD were implanted in 14 sites of RANDO phantom to measure average tissue absorbed dose in thyroid gland, parotid glands, submandibular glands, sublingual gland, lenses and buccal skin. The Promax (PLANMECA, Helsinki, Finland unit was selected for Panoramic, conventional linear tomography and cone beam computed tomography examinations and spiral Hispeed/Fxi (General Electric,USA was selected for CT examination. The average tissue absorbed doses were used for the calculation of the equivalent and effective doses in each organ."nResults: The average absorbed dose for Panoramic ranged from 0.038 mGY (Buccal skin to 0.308 mGY (submandibular gland, linear tomography ranged from 0.048 mGY (Lens to 0.510 mGY (submandibular gland,CBCT ranged from 0.322 mGY (thyroid glad to 1.144 mGY (Parotid gland and in CT ranged from 2.495 mGY (sublingual gland to 3.424 mGY (submandibular gland. Total effective dose in CBCT is 5 times greater than Panoramic and 4 times greater than linear tomography, and in CT, 30 and 22 times greater than Panoramic and linear tomography, respectively. Total effective dose in CT is 6 times greater than CBCT."nConclusion: For obtaining 3-dimensional (3D information in maxillofacial region, CBCT delivers the lower dose than CT, and should be preferred over a medical CT imaging. Furthermore, during maxillofacial imaging, salivary glands receive the highest dose of radiation.

  6. Computed tomography of the acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ho Young; Suh, Jin Suck; Park, Chang Yun; Lee, Kil Woo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1986-04-15

    In a retrospective study of 21 patients, in whom the acetabular fractures were suspected on initial radiographs, we compared and analysed the computed tomographic findings and plain radiographic findings. The results were as follow: 1. In patients with multiple trauma, no further change in position was required during CT examinations. 2. CT showed intraarticular loose bodies, which were invisible on plain radiographs. 3. CT was useful in detecting the fractures of acetabular rims, medial wall of acetabulum, and femoral head. 4. CT permitted better evaluation of shape, extent, and degree of separation of fracture fragments. 5. CT was helpful in detecting the associated fractures and soft tissue injuries. 6. CT also demonstrated the adequacy of reduction, the position of metallic fixation devices, and the presence or absence of remaining intraarticular osseous fragments after surgery.

  7. Comparison of computed tomography scout based reference point localization to conventional film and axial computed tomography.

    Science.gov (United States)

    Jiang, Lan; Templeton, Alistair; Turian, Julius; Kirk, Michael; Zusag, Thomas; Chu, James C H

    2011-01-01

    Identification of source positions after implantation is an important step in brachytherapy planning. Reconstruction is traditionally performed from films taken by conventional simulators, but these are gradually being replaced in the clinic by computed tomography (CT) simulators. The present study explored the use of a scout image-based reconstruction algorithm that replaces the use of traditional film, while exhibiting low sensitivity to metal-induced artifacts that can appear in 3D CT methods. In addition, the accuracy of an in-house graphical software implementation of scout-based reconstruction was compared with seed location reconstructions for 2 phantoms by conventional simulator and CT measurements. One phantom was constructed using a planar fixed grid of 1.5-mm diameter ball bearings (BBs) with 40-mm spacing. The second was a Fletcher-Suit applicator embedded in Styrofoam (Dow Chemical Co., Midland, MI) with one 3.2-mm-diameter BB inserted into each of 6 surrounding holes. Conventional simulator, kilovoltage CT (kVCT), megavoltage CT, and scout-based methods were evaluated by their ability to calculate the distance between seeds (40 mm for the fixed grid, 30-120 mm in Fletcher-Suit). All methods were able to reconstruct the fixed grid distances with an average deviation of <1%. The worst single deviations (approximately 6%) were exhibited in the 2 volumetric CT methods. In the Fletcher-Suit phantom, the intermodality agreement was within approximately 3%, with the conventional sim measuring marginally larger distances, with kVCT the smallest. All of the established reconstruction methods exhibited similar abilities to detect the distances between BBs. The 3D CT-based methods, with lower axial resolution, showed more variation, particularly with the smaller BBs. With a software implementation, scout-based reconstruction is an appealing approach because it simplifies data acquisition over film-based reconstruction without requiring any specialized equipment

  8. Computed tomography of human joints and radioactive waste drums

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, E; Bernardi, R; Hollerbach, K; Logan, C; Martz, H; Roberson, G P

    1999-06-01

    X- and gamma-ray imaging techniques in nondestructive evaluation (NDE) and assay (NDA) have been increasing use in an array of industrial, environmental, military, and medical applications. Much of this growth in recent years is attributed to the rapid development of computed tomography (CT) and the use of NDE throughout the life-cycle of a product. Two diverse examples of CT are discussed. (1) The computational approach to normal joint kinematics and prosthetic joint analysis offers an opportunity to evaluate and improve prosthetic human joint replacements before they are manufactured or surgically implanted. Computed tomography data from scanned joints are segmented, resulting in the identification of bone and other tissues of interest, with emphasis on the articular surfaces. (2) They are developing NDE and NDE techniques to analyze closed waste drums accurately and quantitatively. Active and passive computed tomography (A and PCT) is a comprehensive and accurate gamma-ray NDA method that can identify all detectable radioisotopes present in a container and measure their radioactivity.

  9. Initial water quantification results using neutron computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.K. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States)], E-mail: axh174@psu.edu; Shi, L.; Brenizer, J.S.; Mench, M.M. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States)

    2009-06-21

    Neutron computed tomography is an important imaging tool in the field of non-destructive testing and in fundamental research for many engineering applications. Contrary to X-rays, neutrons can be attenuated by some light materials, such as hydrogen, but can penetrate many heavy materials. Thus, neutron computed tomography is useful in obtaining important three-dimensional information about a sample's interior structure and material properties that other traditional methods cannot provide. The neutron computed tomography system at Pennsylvania State University's Radiation Science and Engineering Center is being utilized to develop a water quantification technique for investigation of water distribution in fuel cells under normal conditions. A hollow aluminum cylinder test sample filled with a known volume of water was constructed for purposes of testing the quantification technique. Transmission images of the test sample at different angles were easily acquired through the synthesis of a dedicated image acquisition computer driving a rotary table controller and an in-house developed synchronization software package. After data acquisition, Octopus (version 8.2) and VGStudio Max (version 1.2) were used to perform cross-sectional and three-dimensional reconstructions of the sample, respectively. The initial reconstructions and water quantification results are presented.

  10. Brain computed tomography of the hypertensive patients

    Energy Technology Data Exchange (ETDEWEB)

    Bae, W. K.; Park, C. K.; Cho, O. K.; Hahm, C. K. [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1980-12-15

    Now a day, hypertension is more increasing in frequency and ranked the top of the causes of death in Korea and other nations. Most of cerebrovascular accidents in hypertensive patients are composed of vascular occlusive changes and hemorrhages. In cerebral angiogram, we can only detect occlusion of large artery and large mass effect from hematoma or cerebral infarction without identification of its entity. The computed tomogram, however, is the best way for evaluation of cerebrovascular diseases including detection of nature, location, amount, and associated changes. This study includes evaluation of computed tomograms of 106 patients with hypertension during the period of 17 months from Feb. 1979 to June 1980 in the department of radiology, college of Medicine, Hanyang University. The results were as follows. 1. Age distribution of the total 106 patients was broad ranging from 25 years to 76 years. 67.9% of patients were over the age of 50. The male and female sex ratio was 3:2. 2. 28 out of 106 patients were normal and 78 patients revealed abnormal on C. T. findings; those were intracranial hemorrhage (35 patients), cerebral infarction (32 patients) and brain atrophy (11 patients). 3. All of the intracranial hemorrhage except one were intracerebral hemorrhage; those were located in the cerebral hemisphere (19 patients), basal ganglia (15 patients) and brain stem (1 patient). The except one case of intracranial hemorrhage was subdural hematoma. 7 patients of intraventricular hemorrhage and 1 patient of subarachnoid hemorrhage were combined with intracerebral hemorrhage. 2/3 of patients who had hemorrhage in cerebral hemisphere revealed lesions in the parietal and temporal lobes. 4. In cases of cerebral infarction, the cerebral hemisphere was most common site of lesion (20 cases), and the next was basal ganglia (11 cases). Most of the infarcts in cerebral hemisphere were located in the parietal and temporal lobes. The left basal ganglia was more commonly involved

  11. Computed Tomography of the Normal Bovine Tarsus.

    Science.gov (United States)

    Hagag, U; Tawfiek, M; Brehm, W; Gerlach, K

    2016-12-01

    The objective of this study was to provide a detailed multiplanar computed tomographic (CT) anatomic reference for the bovine tarsus. The tarsal regions from twelve healthy adult cow cadavers were scanned in both soft and bone windows via a 16-slice multidetector CT scanner. Tarsi were frozen at -20(o) C and sectioned to 10-mm-thick slices in transverse, dorsal and sagittal planes respecting the imaging protocol. The frozen sections were cleaned and then photographed. Anatomic structures were identified, labelled and compared with the corresponding CT images. The sagittal plane was indispensable for evaluation of bone contours, the dorsal plane was valuable in examination of the collateral ligaments, and both were beneficial for assessment of the tarsal joint articulations. CT images allowed excellent delineation between the cortex and medulla of bones, and the trabecular structure was clearly depicted. The tarsal soft tissues showed variable shades of grey, and the synovial fluid was the lowest attenuated structure. This study provided full assessment of the clinically relevant anatomic structures of the bovine tarsal joint. This technique may be of value when results from other diagnostic imaging techniques are indecisive. Images presented in this study should serve as a basic CT reference and assist in the interpretation of various bovine tarsal pathology. © 2016 Blackwell Verlag GmbH.

  12. Role of computed tomography in pancreatic trauma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Hee; Kim, Ki Whang; Lee, Jong Tae; Oh, Sei Jung [College of Medicine, Yonsei University, Seoul (Korea, Republic of)

    1991-03-15

    At Yonsei University Hospital from January 1984 to August 1990, computed tomographic (CT) scans of 13 patients with surgically proven pancreatic injuries after blunt abdominal trauma, including 6 pancreatic lacerations or contusions, 6 pancreatic fractures, and one post-traumatic pseudocyst, were retrospectively reviewed to determine the role and accuracy of the CT in evaluating pancreatic injury. CT can document gross pancreatic injury by showing focal or diffuse enlargement (1), area of diminished attenuation (3), separation (5), focal hematoma (2), and peripancreatic change, including peripancreatic hematoma (2), fluid collection (11), perirenal fascial thickening (10), omental and mesenteric change (5), and bowel change (2). CT correctly diagnosed pancreatic fracture in 5 cases, post-raumatic pseudocyst in 1 case, and pancreatic laceration in 3 cases in 9 of these patients. There were 4 false negative diagnoses, including 3 pancreatic lacerations and 1 pancreatic fracture. A CT is of pancreatic trauma could be difficult to diagnosis in patients who are scanned within 24 hrs after an injury or to distinguish a motion or streak artifact caused by a nasogastric tube or air-oral contrast fluid level in the stomach.

  13. High Resolution Muon Computed Tomography at Neutrino Beam Facilities

    CERN Document Server

    Suerfu, Burkhant

    2015-01-01

    X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pio...

  14. Didactics and training in cardiovascular computed tomography angiography.

    Science.gov (United States)

    Bhojraj, Sanjay D; Al-Mallah, Mouaz H

    2009-01-01

    As the role of cardiovascular computed tomography angiography (CCTA) is further expanded through research, the use of this technology will expand as a result of demand both from medical professionals and the public. To ensure a standardized quality of interpretation of these scans in the face of an increased demand for physicians qualified to interpret these studies, the Society of Cardiovascular Computed Tomography, along with several other professional societies, has proposed a didactic curriculum for the study of CCTA. This review highlights the currently proposed didactic curriculum for the study of CCTA, examines current trends in training for both medical trainees and physicians in practice, and proposes future directions for the study of CCTA.

  15. Project of evaluation of doses in computed tomography in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Slusarczyk-Kacprzyk, W.; Skrzynski, W.; Bulski, W. [Centre of Oncology, Medical Physics Dept., Warsaw (Poland)

    2006-07-01

    Project of evaluation of doses in computed tomography in Poland bases on the organization solutions implemented and evaluated at one of Polish oncological centres. In this study we analyzed doses for a group of 484 patients who underwent an examination with a G.E. HiSpeed CT scanner at the Centre of Oncology in Warsaw. Patient doses (weighted computed tomography dose index, C.T.D.I.w. and dose length product, D.L.P.) have been compared against reference values published by the Polish Ministry of Health. We found that typical patient doses do not exceed reference values. As reference dose levels are defined only for a standard-size patients, sometimes they may be exceeded for a properly done examination. Polish reference dose levels are not based on up-to-date data and should be revised. (authors)

  16. Mandibular condyle position in cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Hyoung Joo; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Kyung Hee Univ. School of Dentistry, Seoul (Korea, Republic of)

    2006-06-15

    To evaluate position of the mandibular condyle within articular fossa in an asymptomatic population radiographically by a cone beam computed tomography. Cone beam computed tomography of 60 temporomandibular joints was performed on 15 males and 15 females with no history of any temporomandibular disorders, or any other orthodontic or photoconductors treatments. Position of mandibular condyle within articular fossa at centric occlusion was evaluated. A statistical evaluation was done using a SPSS. In the sagittal views, mandibular condyle within articular fossa was laterally located at central section. Mandibular condyles in the right and left sides were showed asymmetric positional relationship at medial, central, and lateral sections. Mandibular condyle within articular fossa in an asymptomatic population was observed non-concentric position in the sagittal and coronal views.

  17. Common findings and pseudolesions at computed tomography colonography: pictorial essay

    OpenAIRE

    Augusto Castelli von Atzingen; Dario Ariel Tiferes; Carlos Alberto Matsumoto; Thiago Franchi Nunes; Marcos Vinicius Alvim Soares Maia; Giuseppe D'Ippolito

    2012-01-01

    Computed tomography colonography is a minimally invasive method for screening for polyps and colorectal cancer, with extremely unusual complications, increasingly used in the clinical practice. In the last decade, developments in bowel preparation, imaging, and in the training of investigators have determined a significant increase in the method sensitivity. Images interpretation is accomplished through a combined analysis of two-dimensional source images and several types of three-dimensiona...

  18. Moulding process characterization of paper bottles using computed tomography

    DEFF Research Database (Denmark)

    Saxena, Prateek; Bissacco, Giuliano

    2016-01-01

    The paper presents an approach of evaluating the moulding process for production of paper bottlesusing Computed Tomography (CT). Moulded Pulp Products (MPP) are made of a formed, dewateredand dried mixture of pulp fibers and water. Modern industrial pulp moulding is datedback to the year 1903 when...... a patent for MPP production was acquired by Martin L. Keyes1. Withan increasing demand for environmental friendly products, researchers are now focusing on investigatingadvance manufacturing process for production of MPP2....

  19. Computed tomography-based subclassification of chronic obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Dirksen, Asger; Wille, Mathilde M W

    2016-01-01

    Computed tomography (CT) is an obvious modality for subclassification of COPD. Traditionally, the pulmonary involvement of chronic obstructive pulmonary disease (COPD) in smokers is understood as a combination of deleterious effects of smoking on small airways (chronic bronchitis and small airways...... observed in COPD are subtle. Furthermore, recent results indicate that emphysema may also be the essential pathophysiologic mechanism behind the airflow limitation of COPD. The definition of COPD excludes bronchiectasis as a symptomatic subtype of COPD, and CT findings in chronic bronchitis...

  20. Computed tomography changes following cryotherapy for hepatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    King, J.; Morris, D. L. [University of NSW, Sydney (Australia). Department of Surgery; Glenn, D. [St George Hospital, Kogarah, Sydney (Australia). Department of Radiology

    1997-05-01

    Encouraging survival and tumour marker results have been described in patients where the focally destructive technique, hepatic cryotherapy, is used to treat primary and secondary hepatic malignancy. Radiology allows assessment of the cryotherapy procedure and follow-up treatment. This paper aims to review and describe the appearance of hepatic cryotherapy by computed tomography which allows assessment of the adequacy of surgical technique and offers the ability to identify recurrences that may be suitable for further treatment. 11 refs., 1 tab., 9 figs.

  1. Predicting Neck Abscess with Contrast-Enhanced Computed Tomography

    OpenAIRE

    2014-01-01

    Neck abscesses are difficult to diagnose and treat. Currently, contrast-enhanced computed tomography (CECT) is the imaging modality of choice. The study aims to determine the predictive value of CECT findings in diagnosing neck abscess, causes of neck abscess and the most common neck space involved in the local population. 84 consecutive patients clinically suspected to have neck abscess who underwent CECT and surgical confirmation of pus were included. Demographic and clinical data were reco...

  2. Use of Cone Beam Computed Tomography in Endodontics

    Science.gov (United States)

    Scarfe, William C.; Levin, Martin D.; Gane, David; Farman, Allan G.

    2009-01-01

    Cone Beam Computed Tomography (CBCT) is a diagnostic imaging modality that provides high-quality, accurate three-dimensional (3D) representations of the osseous elements of the maxillofacial skeleton. CBCT systems are available that provide small field of view images at low dose with sufficient spatial resolution for applications in endodontic diagnosis, treatment guidance, and posttreatment evaluation. This article provides a literature review and pictorial demonstration of CBCT as an imaging adjunct for endodontics. PMID:20379362

  3. The role of computed tomography in modern paediatric uroradiology

    Energy Technology Data Exchange (ETDEWEB)

    Maudgil, D.D.; McHugh, K. E-mail: kmchugh@gosh.nhs.uk

    2002-08-01

    Computed tomography (CT) has developed a well-recognised role within paediatric uroradiology, especially in imaging of trauma, malignancy (in particular Wilms' tumour), atypical infection, and congenital urogenital abnormalities. CT can also be used for problem solving in nephrolithiasis and renal transplant assessment. These applications are illustrated and discussed, with an emphasis on particular information that can be gained from the CT study.

  4. Contraindications to lumbar puncture as defined by computed cranial tomography.

    OpenAIRE

    Gower, D. J.; Baker, A. L.; Bell, W O; Ball, M R

    1987-01-01

    Papilloedema is not always an adequate predictor of potential complications from lumbar puncture, and many clinicians are using computed tomography (CT) before lumbar puncture in an effort to identify more accurately the "at risk" patient. This paper identifies the following anatomical criteria defined by CT scanning that correlate with unequal pressures between intracranial compartments and predispose a patient to herniation following decompression of the spinal compartment: lateral shift of...

  5. Computed tomography angiography in the investigation of carotid stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, A.J.P.; Mendelow, A.D.; Birchall, D

    2001-07-01

    The assessment of carotid atherosclerotic disease is an essential pre-requisite for determining a patients suitability for carotid endarterectomy to prevent ischaemic stroke. Catheter angiography is regarded as the most accurate investigative tool for this purpose. However, with its finite morbidity and invasiveness, there is an increasing reliance upon non-invasive methods to accurately assess carotid disease. We present a review of the technique and applications of computed tomography angiography. Goddard, A.J. P.et al. (2001)

  6. Ureterolithiasis: classical and atypical findings on unenhanced helical computed tomography.

    Science.gov (United States)

    Vaswani, Kuldeep K; El-Dieb, Adam; Vitellas, Kenneth M; Bennett, William F; Bova, James G

    2002-03-01

    Evaluation of patients with acute flank pain using helical computed tomography (CT) is a well-accepted, rapid, and safe procedure in the emergency setting. Various primary and secondary signs are described in the literature for evaluation of these patients. Our purpose is to demonstrate both the classical findings associated with ureteral calculi on unenhanced helical CT and atypical findings and potential pitfalls. We also provide readers with a systematic approach to interpreting unenhanced helical CT scans performed for acute flank pain.

  7. Use of Cone Beam Computed Tomography in Endodontics

    OpenAIRE

    Scarfe, William C.; Martin D. Levin; David Gane; Farman, Allan G.

    2009-01-01

    Cone Beam Computed Tomography (CBCT) is a diagnostic imaging modality that provides high-quality, accurate three-dimensional (3D) representations of the osseous elements of the maxillofacial skeleton. CBCT systems are available that provide small field of view images at low dose with sufficient spatial resolution for applications in endodontic diagnosis, treatment guidance, and posttreatment evaluation. This article provides a literature review and pictorial demonstration of CBCT as an imagin...

  8. Hypoplasia of the parotid gland: computed tomography sialography diagnosis.

    Science.gov (United States)

    Sun, Lisha; Sun, Zhipeng; Ma, Xuchen

    2013-10-01

    We report two unusual cases of non-syndromic hypoplasia of the parotid gland. The hypoplastic parotid gland mimicked a preauricular parotid tumor in one case and presented as an incidental image finding in the other case. Absence of the deep lobe and isthmus of the parotid parenchyma could be determined on axial computed tomography (CT) by revealing fat tissue composition of the parotid space. The underdeveloped superficial lobe of the gland was observed on three-dimensional CT sialography.

  9. Computed tomography of common congenital lesions of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Yuen, H.Y. E-mail: drhyyuen@doctors.org.uk; Ahuja, A.T.; Wong, K.T.; Yue, V.; Hasselt, A.C. van

    2003-09-01

    This pictorial review describes the application of high-resolution computed tomography to the investigation and pre-operative work-up of the common lesions of congenital hearing loss, including congenital aural dysplasia, various congenital ossicular anomalies, inner ear dysmorphology, large vestibular aqueduct syndrome, and congenital absence of cochlear nerve and labyrinthitis ossificans from previous infection. The aim is to help radiologists to provide a more accurate diagnosis of underlying aetiology and assist in surgical planning.

  10. Computed tomography of partial unilateral agenesis of the pectoralis muscles.

    Science.gov (United States)

    Demos, T C; Johnson, C; Love, L; Posniak, H

    1985-01-01

    The most common congenitally absent muscles are the pectoralis major and minor. Absence is usually incomplete. This anomaly is often one component of a syndrome associated with other hand (Poland syndrome) and thoracic anomalies. Computed tomography can identify partial absence of the pectoralis muscle and exactly define the altered anatomy. A patient with myasthenia gravis and isolated partial agenesis of the pectoralis muscle is presented.

  11. Analysis of Multilayered Printed Circuit Boards using Computed Tomography

    Science.gov (United States)

    2014-05-01

    resistors harder to identify as Carbon is lower in the periodic table than Aluminium Oxide . Sample 2: Colour Bar Appendix D.2...Aluminium Al2O3 Aluminium Oxide BGA Ball Grid Array Coronal XZ Plane COTS Commercial Off The Shelf C Carbon CT Computed Tomography DC Direct Current...encapsulated in steel housing. Red Circle: Thin film resistors harder to identify as Carbon is lower in the periodic table than Aluminium Oxide . Sample 2

  12. Soil Macropore Structure Characterized by X-Ray Computed Tomography

    Institute of Scientific and Technical Information of China (English)

    FENG Jie; ZHANG Jia-Bao; ZHU An-Ning; BI Jing-Wei

    2003-01-01

    Undisturbed soil core with many macropores and disturbed soil core with only one macropore (diameter is 10 mm) were probed by x-ray computed tomography (CT). The size, number, shape and continuity of macropores in the transverse and vertical sections of soil were characterized using CT scanning images. The probability densities of macropores in the transverse section of soil core exhibited a logarithmic Γ distribution.Results indicated that CT scanning was a promising nondestructive method for characterizing macropores in soils.

  13. Role of computed tomography in the study of vascular pathology

    Energy Technology Data Exchange (ETDEWEB)

    Procacci, C.; Bicego, E.; Bergamo, I.A. and others

    1988-01-01

    The most important indications to the use of computed tomography (CT) in the study of vascular pathology are considered. They may be divided as follows: 1) demonstration of vascular involvement by thoraco-abdominal neoplasms; 2) differential diagnosis between primary vascular and extra-vascular pathology; 3) assessment of primary arterial pathology. For each group, those pathologies are considered, for which CT plays a fundamental role.

  14. Computed tomography of the pathological temporal bone. Malformations. Otospongiosis

    Energy Technology Data Exchange (ETDEWEB)

    Azais, O.; Drouineau, J.; Vandermarcq, P.; Barret, D.; Gasquet, C.

    1988-01-01

    The authors evaluate the value of computed tomography in the investigation of malformations and otospongiosis of the ear. Although the CT scan appears to be essential in the preoperative of malformations of the ear, especially as otological examination frequently contributes little to the evaluation of the middle ear, otospongiosis seems to be a less formal indication, except in the predominantly cochlear forms of the disease.

  15. Computed tomography in patients with Ehlers-Danlos syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Hagino, Hiroshi; Sugitani, Akitoshi; Eda, Isematsu; Takashima, Sachio; Takeshita, Kenzo

    1985-09-01

    Three patients with Ehlers-Danlos syndrome were reported. Unusual findings on computed tomography were seen in two of the three patients. One case showed peculiar and marked dilatation of the 4th ventricle, supracerebellar cistern and lateral ventricle. The other case presented disproportionate enlargement of the anterior horn of the lateral ventricle. These CT findings in the two patients suggest that developmental abnormalities may constitute a structural defect.

  16. Non-obstructive coronary artery disease assessed by coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Nielsen, L.; Bøtker, H. E.; Sorensen, H.;

    2015-01-01

    Introduction: Coronary CT angiography (CTA) detects non-obstructive coronary artery disease (CAD) that may not be recognized by functional testing, but the prognostic impact is not well understood. This study aimed to compare the risk of myocardial infarction (MI) and all-cause mortality...... in patients without or with non-obstructive and obstructive CAD assessed by coronary CTA. Methods: Consecutive patients without known coronary artery disease (CAD) and with chest pain who underwent coronary CTA (>64-detector row) between January 2007 and December 2012 in the 10 centers participating.......35, 95% CI: 3.35-5.65) Ag levels had an increased risk of subsequent MI when compared to patients without CAD. In addition, the risk of MI was increased among patients with 1-, 2-, and 3- vessel/LM obstructive disease with HRs of 4.31 (95% CI: 3.70-5.02), 4.55 (95% CI: 3.72-5.56), and 6.07 (95% CI: 4...

  17. Dosimetry in abdominal imaging by 6-slice computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Sonia Isabel [Hospital de Faro, EPE (Portugal); Abrantes, Antonio Fernando; Ribeiro, Luis Pedro; Almeida, Rui Pedro Pereira [University of Algarve (Portugal). School of Health. Dept. of Radiology

    2012-11-15

    Objective: To determine the effective dose in abdominal computed tomography imaging and to study the influence of patients' characteristics on the received dose. Materials and Methods: Dose values measurements were performed with an ionization chamber on phantoms to check the agreement between dose values and those presented by the computed tomography apparatus, besides their compliance with the recommended reference dose levels. Later, values of dose received by physically able patients submitted to abdominal computed tomography (n = 100) were measured and correlated with their anthropometric characteristics. Finally, the dose to organs was simulated with the Monte Carlo method using the CT-Expo V 1.5 software, and the effect of automatic exposure control on such examinations. Results: The main characteristics directly influencing the dose include the patients' body mass, abdominal perimeter and body mass index, whose correlation is linear and positive. Conclusion: The radiation dose received from abdominal CT scans depends on some patient's characteristics, and it is important to adjust the acquisition parameters to their dimensions (author)

  18. Multidetector computed tomography in the preoperative staging of gastric adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Ricardo Hoelz de Oliveira; Penachim, Thiago Jose; Martins, Daniel Lahan; Andreollo, Nelson Adami; Caserta, Nelson Marcio Gomes, E-mail: rhobarros@hotmail.com [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil)

    2015-03-15

    Objective: To evaluate the role of multidetector computed tomography in the preoperative investigation of tumor invasion depth and lymph node and metastatic involvement according to the TNM classification, in patients with gastric adenocarcinoma. Materials and Methods: Fifty-four patients with biopsy-confirmed gastric cancer underwent preoperative staging with 64-channel multidetector computed tomography. Two independent radiologists analyzed the images and classified the findings. Sensitivity, specificity, accuracy and overall accuracy were calculated for each observer. The interobserver agreement was also evaluated. Results: The accuracy in the classification of categories T ranged from 74% to 96% for observer 1 and from 80% to 92% for observer 2. The overall accuracy was 70% for both observers. The weighted kappa index was 0.75, consistent with a significant interobserver agreement. The accuracy in the classification of lymph node involvement (category N) ranged from 55% to 79% for observer 1 and from 73% to 82% for observer 2. The evaluation of metastatic involvement showed an overall accuracy of 89.6% for both observers. Conclusion: 64-channel multidetector computed tomography demonstrated clinically relevant accuracy in the preoperative staging of gastric adenocarcinoma as regards invasion depth (T category) and metastatic involvement (M category). (author)

  19. Helical computed tomography in the assessment of abdominal aortic pathology

    Energy Technology Data Exchange (ETDEWEB)

    Vicaretti, M.; Young, N.; Jenkins, J.; Fletcher, J. [Westmead Hospital, Westmead, NSW (Australia)

    1997-05-01

    A pilot study was undertaken to evaluate the role of helical computed tomography in the assessment of abdominal aortic pathology. A total of 17 patients underwent intra-arterial digital subtraction angiography (IADSA) and helical computed tomography, with eight patients undergoing subsequent operative intervention. A comparison of radiological findings between IADSA and helical computed tomography (CT) was made and, where applicable, a comparison was made with operative findings. Pathology included abdominal aortic aneurysm (AAA) (n=12), thoraco abdominal aneurysm (n=2) and dissection (n=1), graft distension following AAA repair (n=1) and plaque haemorrhage in the distal aorta following percutaneous transluminal angioplasty (PTA) of the iliac artery (n=1). Planned operative management as based on pre-operative helical CT imaging findings, in particular with reference to the type of graft used (straight or bifurcated) was not changed at operation. Our findings on helical CT in regards to AAA, thoraco-abdominal aneurysm and dissection correlated well with angiography and surgery findings. (authors). 26 refs., 2 tabs., 5 figs.

  20. Efficacy of multislice computed tomography for gastroenteric and hepatic surgeries

    Institute of Scientific and Technical Information of China (English)

    Hiroshi Ohtani; Mitsuo Tsubakimoto; Hidemi Kawajiri; Yuichi Arimoto; Koichi Ohno; Yasuhisa Fujimoto; Hiroko Oba; Kenji Adachi; Masaya Hirano; Shoichi Terakawa

    2005-01-01

    AIM: To determine the efficacy of multislice CT for gastroenteric and hepatic surgery.METHODS: Dual-phase helical computed tomography was performed in 50 of 51 patients who underwent gastroenteric and hepatic surgeries. Twenty-eight, eighteen and four patients suffering from colorectal cancer, gastric cancer,and liver cancer respectively underwent colorectal surgery (laparoscopic surgery: 6 cases), gastrectomy, and hepatectomy. Three-dimensional computed tomography imaging of the inferior mesenteric artery, celiac artery and hepatic artery was performed. And in the follow-up examination of postoperative patients, multiplanar reconstruction image was made in case of need.RESULTS: Scans in 50 patients were technically satisfactory and included in the analysis. Depiction of major visceral arteries, which were important for surgery and other treatments, could be done in all patients.Preoperative visualization of the left colic artery and sigmoidal arteries, the celiac artery and its branches, and hepatic artery was very useful to lymph node dissection,the planning of a reservoir and hepatectomy. And multiplanar reconstruction image was helpful to diagnosis for the postoperative follow-up of patients.CONCLUSION: Three-dimensional volume rendering or multiplanar reconstruction imaging performed by multislice computed tomography was very useful for gastroenteric and hepatic surgeries.

  1. Anatomical structure of lingual foramen in cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ki, Min Woo; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    2004-07-15

    To evaluate whether cone beam computed tomography can depict the distribution, position, frequency, relative vertical dimension, and the diameter of the lingual foramen and direction of lingual bone canal. Cone beam computed tomography of mandible was performed on 25 males and 25 females with no history of any orthodontic treatments or any other dental surgeries. A statistical comparison was done on the mean values of males and females. In the location and distribution of lingual foramina, median lingual foramen was found in all subjects and lateral lingual foramen in 58%. In the lateral lingual foramen, bilateral type was found in 28% and unilateral type in 30%. In the number of lingual foramina, median lingual foramen had two foramina and lateral lingual foramen had one foramen, mostly. In the relative mean vertical dimension of lingual foramina, median lingual foramen was 0.03 {+-} 0.08, and both lateral lingual foramina was 0.20 {+-} 0.04. The mean diameter of lingual foramina, median lingual foramen was 0.9 mm {+-} 0.28, right lateral lingual foramen was 0.92 mm {+-} 0.23, and left lateral lingual foramen was 0.88 mm {+-} 0.27. The most frequent direction of the lingual bone canals, median lingual bone canal proceeded in anteroinferior direction and lateral lingual bone canal in anterosuperolateral direction. Cone beam computed tomography can be helpful for surgery and implantation on the mandibular area. Radiologist should be aware of this anatomical feature and its possible implications.

  2. SADMFR guidelines for the use of Cone-Beam Computed Tomography/ Digital Volume Tomography.

    Science.gov (United States)

    Dula, Karl; Bornstein, Michael M; Buser, Daniel; Dagassan-Berndt, Dorothea; Ettlin, Dominik A; Filippi, Andreas; Gabioud, François; Katsaros, Christos; Krastl, Gabriel; Lambrecht, J Thomas; Lauber, Roland; Luebbers, Heinz-Theo; Pazera, Pawel; Türp, Jens C

    2014-01-01

    Cone-Beam Computed Tomography (CBCT) has been introduced in 1998. This radiological imaging procedure has been provided for dentistry and is comparable to computed tomography (CT) in medicine. It is expected that CBCT will have the same success in dental diagnostic imaging as computed tomography had in medicine. Just as CT is responsible for a significant rise in radiation dose to the population from medical X-ray diagnostics, CBCT studies will be accompanied by a significant increase of the dose to our patients by dentistry. Because of the growing concern for an uncritical and consequently rapidly increasing use of CBCT the Swiss Society of Dentomaxillofacial Radiology convened a first consensus conference in 2011 to formulate indications for CBCT, which can be used as guidelines. In this meeting, oral and maxillofacial surgery, orthodontics and temporomandibular joint disorders and diseases were treated and the most important and most experienced users of DVT in these areas were asked to participate. In general, a highly restrictive use of CBCT is required. Justifying main criterion for CBCT application is that additional, therapy-relevant information is expected that should lead to a significant benefit in patient care. All users of CBCT should have completed a structured, high-level training, just like that offered by the Swiss Society of Dentomaxillofacial Radiology.

  3. Clinical utility of dental cone-beam computed tomography: current perspectives

    Directory of Open Access Journals (Sweden)

    Jaju PP

    2014-04-01

    Full Text Available Prashant P Jaju,1 Sushma P Jaju21Oral Medicine and Radiology, 2Conservative Dentistry and Endodontics, Rishiraj College of Dental Sciences and Research Center, Bhopal, IndiaAbstract: Panoramic radiography and computed tomography were the pillars of maxillofacial diagnosis. With the advent of cone-beam computed tomography, dental practice has seen a paradigm shift. This review article highlights the potential applications of cone-beam computed tomography in the fields of dental implantology and forensic dentistry, and its limitations in maxillofacial diagnosis.Keywords: dental implants, cone-beam computed tomography, panoramic radiography, computed tomography

  4. Computed Tomography and Computed Radiography of late Bronze Age Cremation Urns from Denmark

    DEFF Research Database (Denmark)

    Harvig, Lise Lock; Lynnerup, Niels; Amsgaard Ebsen, Jannie

    2012-01-01

    To improve methods used to study prehistoric cremation rituals, cremation urns from the Danish late Bronze Age were examined using Computed Tomography and Computed Radiography (Digital X-ray). During microexcavation, the digital images were used as registration tool. Our results suggest...

  5. Multi-scale analysis of lung computed tomography images

    CERN Document Server

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

    2007-01-01

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

  6. [Role of cone-beam computed tomography in diagnostic otorhinolaryngological imaging].

    Science.gov (United States)

    Perényi, Ádám; Bella, Zsolt; Baráth, Zoltán; Magyar, Péter; Nagy, Katalin; Rovó, László

    2016-01-10

    Accurate diagnosis and preoperative planning in modern otorhinolaryngology is strongly supported by imaging with enhanced visualization. Computed tomography is often used to examine structures within bone frameworks. Given the hazards of ionizing radiation, repetitive imaging studies exponentially increase the risk of damages to radiosensitive tissues. The authors compare multislice and cone-beam computed tomography and determine the role, advantages and disadvantages of cone-beam computed tomography in otorhinolaryngological imaging. They summarize the knowledge from the international literature and their individual imaging studies. They conclude that cone-beam computed tomography enables high-resolution imaging and reconstruction in any optional plane and in space with considerably lower effective radiation dose. Cone-beam computed tomography with appropriate indications proved to be an excellent diagnostic tool in otorhinolaryngological imaging. It makes an alternative to multislice computed tomography and it is an effective tool in perioperative and postoperative follow-up, especially in those cases which necessitate repetitive imaging with computed tomography.

  7. [Spiral computed tomography in the diagnosis of limb osteomyelitis].

    Science.gov (United States)

    Vasil'ev, A Iu; Bulanova, T V; Onishchenko, M P

    2003-01-01

    The results of radiation studies in 121 patients of different age (4 to 75 years) examined for limb osteomyelitis are analyzed. All the patients underwent routine X-ray study and computed tomography (CT), 26 patients had X-ray fistulography; 8, linear tomography; 10, CT fistulography; 6, scintigraphy, and 15, ultrasound study. Acute hematogenous osteomyelitis (AHO), chronic hematogenous osteomyelitis (CHO), and atypical (here Garre's sclerosing osteomyelitis and Brodie's abscess) osteomyelitis were ascertained in 10.6, 26.4, and 10.1% of cases, respectively. Posttraumatic osteomyelitis was diagnosed in almost 50% of the patients. CT defined the phase of chronic limb osteomyelitis. Spiral CT has proven to be the most effective technique for diagnosing limb osteomyelitis as compared with routine X-ray study: the accuracy of X-ray study was 81.8%, its sensitivity, 84.9%, and specificity, 60.0% and those of computed tomography were 96.7, 99.1, and 80.0%, respectively.

  8. Computed tomography and (18)F-fluorodeoxyglucose positron emission tomography/computed tomography findings in adrenal candidiasis and histoplasmosis: two cases.

    Science.gov (United States)

    Altinmakas, Emre; Guo, Ming; Kundu, Uma R; Habra, Mouhammed Amir; Ng, Chaan

    2015-01-01

    We report the contrast-enhanced computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography findings in adrenal histoplasmosis and candidiasis. Both demonstrated bilateral hypermetabolic heterogeneous adrenal masses with limited wash-out on delayed CT. Adrenal candidiasis has not been previously reported, nor have the CT wash-out findings in either infection. The adrenal imaging findings are indistinguishable from malignancy, which is more common; but in this setting, physicians should be alert to the differential diagnosis of fungal infections, since it can be equally deadly.

  9. Right parietal stroke with Gerstmann's syndrome. Appearance on computed tomography, magnetic resonance imaging, and single-photon emission computed tomography.

    Science.gov (United States)

    Moore, M R; Saver, J L; Johnson, K A; Romero, J A

    1991-04-01

    We examined a patient who exhibited Gerstmann's syndrome (left-right disorientation, finger agnosia, dyscalculia, and dysgraphia) in association with a perioperative stroke in the right parietal lobe. This is the first description of the Gerstmann tetrad occurring in the setting of discrete right hemisphere pathologic findings. A well-localized vascular lesion was demonstrated by computed tomography, magnetic resonance imaging, and single-photon emission computed tomographic studies. The patient had clinical evidence of reversed functional cerebral dominance and radiologic evidence of reversed anatomic cerebral asymmetries.

  10. The role of positron emission tomography/computed tomography in planning radiotherapy in endometrial cancer.

    Science.gov (United States)

    Simcock, Bryony; Narayan, Kailash; Drummond, Elizabeth; Bernshaw, David; Wells, Elizabeth; Hicks, Rodney J

    2015-05-01

    The optimal method of assessing disease distribution in endometrial cancer is widely debated. Knowledge of disease distribution assists in planning adjuvant radiotherapy; in this study we used positron emission tomography/computed tomography (PET/CT) to assess disease distribution before radiotherapy. Seventy-three consecutive patients referred to the Peter MacCallum Cancer Centre for adjuvant radiotherapy for endometrial cancer, with either high-risk disease after a hysterectomy or recurrent disease, had a PET/CT before treatment. The findings on PET/CT and clinical course were recorded. PET/CT found additional disease in 35% of postoperative patients, changing planned treatment in 31%. In the group with known recurrence, additional disease was found in 72%, changing management in 36%. PET/CT is a valuable tool for planning radiotherapy in endometrial cancer.

  11. Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Science.gov (United States)

    Sürücü, Erdem; Demir, Yusuf; Dülger, Ahmet C.; Batur, Abdüssamed; Ölmez, Şehmus; Kitapçı, Mehmet T.

    2016-01-01

    A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT) scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG) uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT. PMID:27751978

  12. Quantitative cone beam X-ray luminescence tomography/X-ray computed tomography imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Dongmei; Zhu, Shouping, E-mail: zhusp2009@gmail.com; Chen, Xueli; Chao, Tiantian; Cao, Xu; Zhao, Fengjun; Huang, Liyu; Liang, Jimin [Engineering Research Center of Molecular and Neuro Imaging of Ministry of Education and School of Life Science and Technology, Xidian University, Xi' an, Shaanxi 710071 (China)

    2014-11-10

    X-ray luminescence tomography (XLT) is an imaging technology based on X-ray-excitable materials. The main purpose of this paper is to obtain quantitative luminescence concentration using the structural information of the X-ray computed tomography (XCT) in the hybrid cone beam XLT/XCT system. A multi-wavelength luminescence cone beam XLT method with the structural a priori information is presented to relieve the severe ill-posedness problem in the cone beam XLT. The nanophosphors and phantom experiments were undertaken to access the linear relationship of the system response. Then, an in vivo mouse experiment was conducted. The in vivo experimental results show that the recovered concentration error as low as 6.67% with the location error of 0.85 mm can be achieved. The results demonstrate that the proposed method can accurately recover the nanophosphor inclusion and realize the quantitative imaging.

  13. Reconstruction Algorithms for Positron Emission Tomography and Single Photon Emission Computed Tomography and their Numerical Implementation

    CERN Document Server

    Fokas, A S; Marinakis, V

    2004-01-01

    The modern imaging techniques of Positron Emission Tomography and of Single Photon Emission Computed Tomography are not only two of the most important tools for studying the functional characteristics of the brain, but they now also play a vital role in several areas of clinical medicine, including neurology, oncology and cardiology. The basic mathematical problems associated with these techniques are the construction of the inverse of the Radon transform and of the inverse of the so called attenuated Radon transform respectively. We first show that, by employing mathematical techniques developed in the theory of nonlinear integrable equations, it is possible to obtain analytic formulas for these two inverse transforms. We then present algorithms for the numerical implementation of these analytic formulas, based on approximating the given data in terms of cubic splines. Several numerical tests are presented which suggest that our algorithms are capable of producing accurate reconstruction for realistic phanto...

  14. Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Erdem Sürücü

    2016-10-01

    Full Text Available A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT.

  15. Diagnostic performance of exercise bicycle testing and single-photon emission computed tomography: Comparison with 64-slice computed tomography coronary angiography

    NARCIS (Netherlands)

    A.C. Weustink (Annick); L.A.E. Neefjes (Lisan); A. Rossi (Alexia); W.B. Meijboom (Willem Bob); K. Nieman (Koen); E. Capuano (Ermanno); H. Boersma (Eric); N.R.A. Mollet (Nico); G.P. Krestin (Gabriel); P.J. de Feyter (Pim)

    2012-01-01

    textabstractTo conduct a comparison of the diagnostic performance of exercise bicycle testing and singlephoton emission computed tomography (SPECT) with computed tomography coronary angiography (CTCA) for the detection of obstructive coronary artery disease (CAD) in patients with stable angina. 376

  16. Utility of emergency cranial computed tomography in patients without trauma.

    Science.gov (United States)

    Narayanan, Vignesh; Keniston, Angela; Albert, Richard K

    2012-09-01

    The objectives of this study were to determine, in patients admitted to the hospital from the emergency department (ED) without evidence of trauma, 1) the prevalence of clinically important abnormalities on cranial computed tomography (CCT) and 2) the frequency of emergent therapeutic interventions required because of these abnormalities. The authors retrospectively reviewed the records of all patients from 2007 between the ages of 18 and 89 years who had CCT as part of their ED evaluations prior to hospitalization. Patients with any indication of trauma were excluded, as were those who had a lumbar puncture (LP). Chief complaint, results of the ED neurologic examination, tomogram findings, and whether patients had emergent interventions were recorded. Patients presenting with altered mental status (AMS) were analyzed separately. Of the 766 patients meeting inclusion criteria, 83 (11%) had focal neurologic findings, and 61 (8%) had clinically important abnormalities on computed tomography. Emergent interventions occurred in only 12 (1.6%), 11 (92%) of whom had focal neurologic findings. In the subgroup of 287 patients with AMS as their presenting problem, 14 (4.9%) had focal findings, six (2%) had clinically important abnormalities on tomography, and only two (0.7%) required emergent interventions, both of whom had focal findings. Patients presenting with AMS were less likely to have positive findings on tomography (odds ratio [OR] = 0.16, 95% confidence interval [CI] = 0.07 to 0.39). Patients presenting with motor weakness or speech abnormalities, or who were unresponsive, were more likely to have positive findings on tomography (OR = 4.7, 95% CI = 2.6 to 8.6; OR = 4.4, 95% CI = 1.5 to 2.7; and OR = 3.3, 95% CI = 1.6 to 7.1, respectively). Of patients without evidence of trauma who receive CCT in the ED, the prevalence of focal neurologic findings and clinically important abnormalities on tomography is low, the need for emergent intervention is very low, and the

  17. Routine Bone Marrow Biopsy Has Little or No Therapeutic Consequence for Positron Emission Tomography/Computed Tomography-Staged Treatment-Naive Patients With Hodgkin Lymphoma

    DEFF Research Database (Denmark)

    El-Galaly, Tarec Christoffer; d´Amore, Francesco; Juul Mylam, Karen

    2012-01-01

    Routine Bone Marrow Biopsy Has Little or No Therapeutic Consequence for Positron Emission Tomography/Computed Tomography-Staged Treatment-Naive Patients With Hodgkin Lymphoma......Routine Bone Marrow Biopsy Has Little or No Therapeutic Consequence for Positron Emission Tomography/Computed Tomography-Staged Treatment-Naive Patients With Hodgkin Lymphoma...

  18. First experiences from Copenhagen with paediatric single photon emission computed tomography/computed tomography

    DEFF Research Database (Denmark)

    Mortensen, Jann; Bech, Birthe Højlund; Højgaard, Liselotte

    2011-01-01

    OBJECTIVE: This study evaluates the diagnostic value of single photon emission computed tomographic (SPECT)/multislice computed tomographic (MSCT) fusion images compared with planar scintigraphy in children. METHODS: Fifteen children [eight girls, mean age 13 years (range 2-17 years)] who were...

  19. F-18 Fluorodeoxy Glucose Positron Emission Tomography/Computed Tomography Findings in a Rare Case of Penile Leiomyosarcoma

    Directory of Open Access Journals (Sweden)

    Kuruva Manohar

    2011-01-01

    Full Text Available Penile cancer is a rare entity accounting for only 0.4% all male malignancies. Penile leiomyosarcomas are even rarer with only around 35 cases reported in literature. We report a rare case of penile leiomyosarcoma illustrating F-18 Fluorodeoxy glucose (FDG positron emission tomography/computed tomography (PET/CT features and histopathology correlation.

  20. Paradigm of pretest risk stratification before coronary computed tomography

    DEFF Research Database (Denmark)

    Jensen, Jesper Møller; Øvrehus, Kristian; Nielsen, Lene H

    2009-01-01

    BACKGROUND: The optimal method of determining the pretest risk of coronary artery disease as a patient selection tool before coronary multidetector computed tomography (MDCT) is unknown. OBJECTIVE: We investigated the ability of 3 different clinical risk scores to predict the outcome of coronary...... by receiver operating characteristic analysis. The distribution of low-, intermediate-, and high-risk persons, respectively, was established and compared for each of the 3 risk models. RESULTS: Overall, all risk prediction models performed equally well. However, the Duke risk model classified the low......-risk patients more correctly than did the other models (P value of the Duke risk model was superior to the other risk models (P

  1. Precision Medicine and PET/Computed Tomography: Challenges and Implementation.

    Science.gov (United States)

    Subramaniam, Rathan M

    2017-01-01

    Precision Medicine is about selecting the right therapy for the right patient, at the right time, specific to the molecular targets expressed by disease or tumors, in the context of patient's environment and lifestyle. Some of the challenges for delivery of precision medicine in oncology include biomarkers for patient selection for enrichment-precision diagnostics, mapping out tumor heterogeneity that contributes to therapy failures, and early therapy assessment to identify resistance to therapies. PET/computed tomography offers solutions in these important areas of challenges and facilitates implementation of precision medicine. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Laryngotracheobronchial papillomatosis: findings on computed tomography scans of the chest

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Radiologia; Araujo Neto, Cesar de [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Dept. de Radiologia; Meirelles, Gustavo Souza Portes [Universidade Federal de Sao Paulo (UNIFESP-EPM), SP (Brazil); Irion, Klaus Loureiro [The Royal Liverpool University Hospital, Liverpool (United Kingdom); Zanetti, Glaucia [Faculdade de Medicina de Petropolis (FMP), RJ (Brazil); Missrie, Israel [Universidade Federal de Sao Paulo (UNIFESP-EPM), SP (Brazil). Dept. de Diagnostico por Imagem; Sato, Juliana [Universidade Federal de Sao Paulo (UNIFESP-EPM), SP (Brazil). Dept. de Otorrinolaringologia e Cirurgia de Cabeca e Pescoco

    2008-12-15

    Objectives: To present the findings of computed tomography (CT) scans of the chest in patients with laryngotracheobronchial papillomatosis. Methods: We retrospectively analyzed CT scans of eight patients, five males and three females, ranging from 5 to 18 years of age with a mean age of 10.5 years. Images were independently reviewed by two radiologists. In discrepant cases, a consensus was reached. Results: The most common CT findings were intratracheal polypoid lesions and pulmonary nodules, many of which were cavitated. Conclusions: In patients with laryngotracheobronchial papillomatosis, the most common tomographic finding was the combination of intratracheal polypoid lesions and multiple pulmonary nodules, many of which were cavitated. (author)

  3. Value of computed tomography in patients with mucopolysaccharidosis

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, J.; Grebell, F.S.

    1987-11-01

    Cranial computed tomography (CT) was performed on 11 cases of mucopolysaccharidosis (MPS) IVA (Morquio syndrome). Our results suggest that although having normal intelligence CT changes may be seen with increasing age. In two cases white matter low density was found and in a third there was gross dilatation of the ventricles, basal cisterns and subarachnoid space. Nine other patients with various types of mucopolysaccharidosis also had cranial CT performed and in general those types associated with mental retardation showed changes although there was an interesting exception involving a case of MPS IIIA who had a normal CT scan.

  4. Computed Tomography Appearances of Various Complications Associated with Pancreatic Pseudocysts

    Energy Technology Data Exchange (ETDEWEB)

    Cheol Kim, Hyun; Mo Yang, Dal; Jung Kim, Hyoung; Ho Lee, Dong; Tae Ko, Young; Won Lim, Joo (Dept. of Radiology, East-West Neo Medical Center, Kyung-Hee Univ., Seoul (Korea))

    2008-09-15

    Most pancreatic pseudocysts are common complications of acute or chronic pancreatitis. They usually occur within the pancreas or in peripancreatic tissues, and are visualized as round or oval fluid collections with thin or thick walls on computed tomography (CT) scans. However, pancreatic pseudocysts are often combined with various complications, e.g., various organ involvements, infection, hemorrhage with pseudoaneurysm formation, rupture with fistula formation, or gastrointestinal or biliary obstruction, which may necessitate prompt intervention or surgery. This review illustrates the CT appearances of various complications associated with pancreatic pseudocysts

  5. Material reconstruction for spectral computed tomography with detector response function

    Science.gov (United States)

    Liu, Jiulong; Gao, Hao

    2016-11-01

    Different from conventional computed tomography (CT), spectral CT using energy-resolved photon-counting detectors is able to provide the unprecedented material compositions. However accurate spectral CT needs to account for the detector response function (DRF), which is often distorted by factors such as pulse pileup and charge-sharing. In this work, we propose material reconstruction methods for spectral CT with DRF. The simulation results suggest that the proposed methods reconstructed more accurate material compositions than the conventional method without DRF. Moreover, the proposed linearized method with linear data fidelity from spectral resampling had improved reconstruction quality from the nonlinear method directly based on nonlinear data fidelity.

  6. Normal postperative computed tomography findings after avariety of pancreatic surgeries

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Ji Won; Hwang, Ho Kyoung; Lee, Min Wook; Kim, Ki Whang; Kang, Chang Moo; Kim, Myeong Jin; Chung, Yong Eun [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    Pancreatic surgery remains the only curative treatment for pancreatic neoplasms, and plays an important role in the management of medically intractable diseases. Since the original Whipple operation in the 20th century, surgical techniques have advanced, resulting in decreased postoperative complications and better clinical outcomes. Normal postoperative imaging findings vary greatly depending on the surgical technique used. Radiologists are required to be familiar with the normal postoperative imaging findings, in order to distinguish from postoperative complications or tumor recurrence. In this study, we briefly review a variety of surgical techniques for the pancreas, and present the normal postoperative computed tomography findings.

  7. Multidetector Computer Tomography: Evaluation of Blunt Chest Trauma in Adults

    Directory of Open Access Journals (Sweden)

    João Palas

    2014-01-01

    Full Text Available Imaging plays an essential part of chest trauma care. By definition, the employed imaging technique in the emergency setting should reach the correct diagnosis as fast as possible. In severe chest blunt trauma, multidetector computer tomography (MDCT has become part of the initial workup, mainly due to its high sensitivity and diagnostic accuracy of the technique for the detection and characterization of thoracic injuries and also due to its wide availability in tertiary care centers. The aim of this paper is to review and illustrate a spectrum of characteristic MDCT findings of blunt traumatic injuries of the chest including the lungs, mediastinum, pleural space, and chest wall.

  8. Computed tomography in the evaluation of thyroid disease

    Energy Technology Data Exchange (ETDEWEB)

    Silverman, P.M.; Newman, G.E.; Korobkin, M.; Workman, J.B.; Moore, A.V.; Coleman, R.E.

    1984-05-01

    Traditionally, thyroid imaging has been performed primarily using radionuclide scanning. High-resolution computed tomography (CT) was performed in 18 patients to evaluate the CT appearance of various thyroid abnormalities including diffuse toxic goiter, multinodular goiter, Hashimoto thyroiditis, thyroid adenoma, and malignant thyroid tumors. CT images of the thyroid were correlated with radionuclide scanning, surgical findings, and clinical and laboratory results. CT provided a complementary method for evaluation of the thyroid by defining the morphology of the thyroid gland and more precisely defining the anatomic extent of thyroid abnormalities in relation to the normal structures of the neck and mediastinum.

  9. Aortic valve area assessed with 320-detector computed tomography

    DEFF Research Database (Denmark)

    Larsen, Linnea Hornbech; Kofoed, Klaus Fuglsang; Carstensen, Helle Gervig;

    2014-01-01

    To evaluate the diagnostic accuracy of aortic valve area (AVA) assessment with 320-detector Computed Tomography (MDCT) compared to transthoracic echocardiography (TTE) in a population with mild to severe aortic valve stenosis. AVA was estimated in 169 patients by planimetry on MDCT images (AVAMDCT......) and by the continuity equation with TTE (AVATTE). To generate a reference AVA (AVAREF) we used the stroke volume from MDCT divided by the velocity time integral from CW Doppler by TTE (according to the continuity equation: stroke volume in LVOT = stroke volume passing the aortic valve). AVAREF was used as the reference...

  10. Multidetector computer tomography: evaluation of blunt chest trauma in adults.

    Science.gov (United States)

    Palas, João; Matos, António P; Mascarenhas, Vasco; Herédia, Vasco; Ramalho, Miguel

    2014-01-01

    Imaging plays an essential part of chest trauma care. By definition, the employed imaging technique in the emergency setting should reach the correct diagnosis as fast as possible. In severe chest blunt trauma, multidetector computer tomography (MDCT) has become part of the initial workup, mainly due to its high sensitivity and diagnostic accuracy of the technique for the detection and characterization of thoracic injuries and also due to its wide availability in tertiary care centers. The aim of this paper is to review and illustrate a spectrum of characteristic MDCT findings of blunt traumatic injuries of the chest including the lungs, mediastinum, pleural space, and chest wall.

  11. Incidental findings on cone beam computed tomography: Relate and relay

    Directory of Open Access Journals (Sweden)

    Suhas P Pande

    2015-01-01

    Full Text Available Objective: To evaluate the presence of incidental findings on cone beam computed tomography (CBCT images and to recognize their clinical importance. Materials and Methods: A total of 700 CBCT scans between January 2013 to August 2014 at Government Dental College and Hospital were evaluated retrospectively. Results: 459 incidental findings (65.57% were observed in 700 patients. Most common individual incidental finding was mucosal thickening (119 followed by pineal/habenula calcification (99 and choroid plexus (77. Conclusion: The oral and maxillofacial radiologist should carefully interpret all scans and should not ignore the incidental findings and hence avoid untoward snowballing effects.

  12. X-ray computed tomography investigations of Cucuteni ceramic statuettes

    Directory of Open Access Journals (Sweden)

    Carmen Pavel

    2013-12-01

    Full Text Available Deciphering the internal structure of prehistoric artefacts can provide spectacular insights that might help us understand the people who made them. In order to preserve the integrity of these relics of past civilisations, it is desirable to make such investigations using non-destructive techniques. Recent decades have witnessed a growth in the X-ray computed tomography (CT applications in the study of cultural heritage objects. This paper presents and discusses tomographic investigations of two Cucuteni ceramic statuettes discovered in Romania. The study was made with a CT device specially designed for archaeometric applications.

  13. Differentiation of orbital cellulitis from preseptal cellulitis by computed tomography.

    Science.gov (United States)

    Goldberg, F; Berne, A S; Oski, F A

    1978-12-01

    Computed tomography (CT) was used in the management of four patients with periorbital inflammation. These patients were selected for CT scanning because of the difficulty, on clinical examination alone, in determining the degree of orbital disease. The CT scans confirmed the presence and defined the location of an orbital abscess in three patients and eliminated the presence of an abscess in the fourth. On the basis of this experience, CT scanning is recommended in the evaluation of children with periorbital inflammation in whom proptosis, ophthalmoplegia, or loss of visual acuity develops, or in whom severe eyelid edema prevents adequate eye examination.

  14. Unusual causes of colonic wall thickening on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Turner, D.R.; Markose, G.; Arends, M.J.; Ng, C.S.; Freeman, A.H

    2003-03-01

    Computed tomography (CT) appearances in 'colitis' are often non-specific, and include mural thickening and mesenteric fat stranding. In the western world, the majority of cases will have, or be subsequently diagnosed with, inflammatory bowel disease, pseudomembranous colitis or ischaemic colitis. However, other rare conditions may also produce these rather non-specific signs. We present a number of cases demonstrating colonic wall thickening on CT due to rarer diagnoses, which are correlated with the histopathological features. Some of these CT appearances have not been described previously in the literature.

  15. Bleeding Meckel's diverticulum diagnosis: an unusual indication for computed tomography.

    Science.gov (United States)

    Danzer, D; Gervaz, P; Platon, A; Poletti, P A

    2003-01-01

    Despite the wide use of modern investigation techniques, the diagnosis of complications related to Meckel's diverticulum (MD) remains difficult. Arteriography is commonly indicated for acute bleeding, and radionuclide scans may help in identifying the site of intestinal hemorrhage. In contrast, computed tomography (CT) is usually considered little use in the diagnosis of bleeding MD. We present the case of a young patient with massive gastrointestinal hemorrhage, in whom the diagnosis of MD bleeding was preoperatively made with contrast-enhanced CT after two negatives arteriographies.

  16. Cone-beam computed tomography: A miracle for orthodontics!

    Directory of Open Access Journals (Sweden)

    Jeevan M Khatri

    2015-01-01

    Full Text Available The branch of oral medicine and radiology has always played a role of back stage worker for the branch of orthodontics and dentofacial orthopaedics. It would have been difficult for an orthodontist to gift the bright smiles to his/her patients without the 2D and 3D black and white pictures provided by the oral radiologist. Moreover, the series of advances in the various imaging modalities are playing the role of a magician for the branch of orthodontia. The present article provides valuable information about one such miracle for the field of orthodontics-cone beam computed tomography (CBCT.

  17. Computed tomography of the thymus gland in myasthenia gravis

    Energy Technology Data Exchange (ETDEWEB)

    Thorvinger, B.; Lyttkens, K.; Samuelsson, L.

    Sixteen consecutive patients with myasthenia gravis were examined by computed tomography (CT) before thymectomy. Surgical and histologic findings were compared with those obtained at CT. The results, like those of most other recent studies, indicate that CT is a reliable method for identifying thymoma. In all three patients with thymoma, and in five out of eight patients with hyperplasia, the lesion was observed at CT, giving an overall accuracy of 80%. Although tymic hyperplasia is a basically histological diagnosis an enlarged gland may give a correct diagnosis of this abnormality.

  18. The value of computed tomography in myasthenia gravis

    Energy Technology Data Exchange (ETDEWEB)

    Brown, L.R.; Muhm, J.R.; Sheedy, P.F. II; Unni, K.K.; Bernatz, P.E.; Hermann, R.C. Jr.

    1983-01-01

    In a 5 year study, 19 patients with myasthenia gravis were studied by computed tomography (CT) and underwent thymectomy. CT was accurate in detecting the nine true thymic masses but could not differentiate thymomas from nonthymomatous masses, including thymic cysts. No thymoma was found in a patient under 25 years of age. In one case, the 18 sec scanner could not differentiate a large gland from a thymoma. In eight cases, glands with histologic thymic hyperplasia and histologically normal thymus appeared to be similar and could not be differentiated by CT.

  19. Urologic applications of multiplanar and three-dimensional computed tomography.

    Science.gov (United States)

    Olson, M C; Posniak, H V

    1995-01-01

    The introduction of helical computed tomography (CT) has resulted in improved quality of multiplanar reformations and three-dimensional reconstructions in the chest and abdomen and has made CT angiography a clinical reality. These imaging techniques are useful for evaluating the urinary tract, adding a new dimension to its display, resulting in improved diagnosis of renal and perirenal disease. This article reviews the indications and techniques utilized for multiplanar and three-dimensional CT for urology. The advantages and limitations are discussed, and normal and pathologic findings in the urinary tract illustrated.

  20. PRaVDA: High Energy Physics towards proton Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Price, T., E-mail: t.price@bham.ac.uk

    2016-07-11

    Proton radiotherapy is an increasingly popular modality for treating cancers of the head and neck, and in paediatrics. To maximise the potential of proton radiotherapy it is essential to know the distribution, and more importantly the proton stopping powers, of the body tissues between the proton beam and the tumour. A stopping power map could be measured directly, and uncertainties in the treatment vastly reduce, if the patient was imaged with protons instead of conventional x-rays. Here we outline the application of technologies developed for High Energy Physics to provide clinical-quality proton Computed Tomography, in so reducing range uncertainties and enhancing the treatment of cancer.

  1. Value of computed tomography scanning in chondromalacia patellae

    Energy Technology Data Exchange (ETDEWEB)

    Boven, F.; Bellemans, M.A.; Geurts, J.; de Boeck, H.; Potvliege, R.

    1982-06-01

    Sixtyseven patients with pain in the knee were studied. A computed tomography (CT) score indicating chondromalacia was devised, based on the results of CT after arthrography. This score takes account of the regularity, the congruity, and the imbibition of contrast material. Thus the patients could be divided into four groups: those who definitely have chondromalacia (++), probably (+), probably not (+-), and definitely not (-). These results were compared with the clinical diagnosis based on clinical signs, arthroscopy, or operation. Eighteen patients had clinically proved chondromalacia, CT scored 14++, 3+ and 1+-. Twentynine patients had no chondromalacia, CT scored 19-, 8+-, and 2+. Twenty patients had an uncertain clinical diagnosis. Arthrography was less accurate in detecting chondromalacia.

  2. Micro Computer Tomography for medical device and pharmaceutical packaging analysis.

    Science.gov (United States)

    Hindelang, Florine; Zurbach, Raphael; Roggo, Yves

    2015-04-10

    Biomedical device and medicine product manufacturing are long processes facing global competition. As technology evolves with time, the level of quality, safety and reliability increases simultaneously. Micro Computer Tomography (Micro CT) is a tool allowing a deep investigation of products: it can contribute to quality improvement. This article presents the numerous applications of Micro CT for medical device and pharmaceutical packaging analysis. The samples investigated confirmed CT suitability for verification of integrity, measurements and defect detections in a non-destructive manner. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Computed tomography in the evaluation of plexopathies and proximal neuropathies

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, J.D. (McGill Univ., Montreal, Quebec (Canada). Dept. of Neurology and Neurosurgery); Schmidt, B. (McGill Univ., Montreal, Quebec (Canada). Dept. of Radiology); Wee, R. (Montreal General Hospital, Quebec (Canada))

    1983-11-01

    The article describes nine patients with plexopathies or proximal mononeuropathies due to mass lesions. In four, computed tomography (CT) was the only radiological technique to show the cause of the neuropathy. In five patients, CT either unequivocally confirmed the presence of an abnormality or was superior to other imaging techniques in showing its full anatomical extent. CT scanning is a valuable aid in the assessment of lesions of the peripheral nervous system, particularly plexopathies and mononeuropathies caused by retroperitoneal, pelvic or superior pulmonary sulcus tumors.

  4. Angiography and computed tomography in cerebro-arterial occlusive diseases

    Energy Technology Data Exchange (ETDEWEB)

    Bradac, G.B.; Oberson, R.

    1983-01-01

    This second edition provides an exposition of occlusive diseases of the extra- and intracranial arterial circulation. The contents include: (1) pathology of the causes of cerebrovascular arterial occlusion; (2) the indications, hazards, technical aspects, and routine technique of cerebral angiography; (3) angiographic findings of the extracranial segments of the circulation to the brain; (4) computed tomography in the diagnosis of cerebrovascular diseases; (5) other investigations in the diagnosis of cerebrovascular occlusive disease; (6) conclusive considerations on the pathogenesis of transient ischemic attacks and infarctions.

  5. PET/Computed Tomography in Renal, Bladder, and Testicular Cancer.

    Science.gov (United States)

    Bouchelouche, Kirsten; Choyke, Peter L

    2015-07-01

    Imaging plays an important role in the clinical management of cancer patients. Hybrid imaging with PET/computed tomography (CT) is having a broad impact in oncology, and in recent years PET/CT is beginning to have an impact in urooncology. In both bladder and renal cancers, there is a need to study the efficacy of other tracers than F-18 fluorodeoxyglucose (FDG), particularly tracers with limited renal excretion. Thus, new tracers are being introduced. This review focuses on the clinical role of FDG and other PET agents in renal, bladder, and testicular cancers.

  6. Improved proton computed tomography by dual modality image reconstruction

    DEFF Research Database (Denmark)

    Hansen, David Christoffer; Bassler, Niels; Petersen, Jørgen B.B.;

    2014-01-01

    Purpose: Proton computed tomography (CT) is a promising image modality for improving the stopping power estimates and dose calculations for particle therapy. However, the finite range of about 33 cm of water of most commercial proton therapy systems limits the sites that can be scanned from a full...... nonlinear conjugate gradient algorithm, minimizing total variation and the x-ray CT prior while remaining consistent with the proton projection data. The proton histories were reconstructed along curved cubic-spline paths. Results: The spatial resolution of the cone beam CT prior was retained for the fully...

  7. Characterizing Green Fiber Bottle Prototypes Using Computed Tomography

    DEFF Research Database (Denmark)

    Saxena, Prateek; Bissacco, Giuliano; Stolfi, Alessandro

    2017-01-01

    in the desired shape and structure. However, there are certain limitations associated to the product characterization using tactile measuring methods. In this work, a new approach has been applied for defect analysis and quality control of non-homogenous prototype paper products using computed tomography.......Due to ever increasing demand of sustainability and biodegradability, there arises a need to develop environmental friendly packaging products. Green fiber bottle is a packaging product for carbonated beverages, made out of cellulose fibers. The production process accounts for moulding paper pulp...

  8. Benign breast lesions detected by positron emission tomography-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Benveniste, Ana P., E-mail: apbenveniste@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Yang, Wei, E-mail: wyang@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Benveniste, Marcelo F., E-mail: mfbenveniste@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Mawlawi, Osama R., E-mail: omawlawi@mdanderson.org [Department of imaging physics, The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Marom, Edith M., E-mail: emarom@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-15

    {sup 18}F-fluorodeoxyglucose positron emission computed tomography (FDG PET-CT) is widely used in the initial staging and response evaluation of patients with malignancy. This review describes a spectrum of benign breast findings incidentally detected by FDG PET-CT at staging that may be misinterpreted as malignancy. We describe the pattern of distribution and intensity of FDG uptake in a spectrum of benign breast diseases with their corresponding typical morphological imaging characteristics to help the nuclear medicine physician and/or general radiologist identify benign lesions, avoiding unnecessary breast imaging work-up and biopsies.

  9. Position emission tomography with or without computed tomography in the primary staging of Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Loft, Annika; Hansen, Mads

    2006-01-01

    BACKGROUND AND OBJECTIVES: In order to receive the most appropriate therapy, patients with Hodgkin's lymphoma (HL) must be accurately stratified into different prognostic staging groups. Computed tomography (CT) plays a pivotal role in the conventional staging. The aim of the present study...... standard limits the reliability of accuracy calculations. RESULTS: FDG-PET would have upstaged 19% of patients and downstaged 5% of patients, leading to a different treatment in 9% of patients. For FDG-PET/CT, the corresponding figures are 17%, 5%, and 7%. In nodal regions, the sensitivity of FDG...

  10. Temporomandibular joint computed tomography: development of a direct sagittal technique

    Energy Technology Data Exchange (ETDEWEB)

    van der Kuijl, B.; Vencken, L.M.; de Bont, L.G.; Boering, G. (Univ. of Groningen, (Netherlands))

    1990-12-01

    Radiology plays an important role in the diagnosis of temporomandibular disorders. Different techniques are used with computed tomography offering simultaneous imaging of bone and soft tissues. It is therefore suited for visualization of the articular disk and may be used in patients with suspected internal derangements and other disorders of the temporomandibular joint. Previous research suggests advantages to direct sagittal scanning, which requires special positioning of the patient and a sophisticated scanning technique. This study describes the development of a new technique of direct sagittal computed tomographic imaging of the temporomandibular joint using a specially designed patient table and internal light visor positioning. No structures other than the patient's head are involved in the imaging process, and misleading artifacts from the arm or the shoulder are eliminated. The use of the scanogram allows precise correction of the condylar axis and selection of exact slice level.

  11. Computed tomography of the craniocervical junction in rheumatoid arthritis.

    Science.gov (United States)

    Castor, W R; Miller, J D; Russell, A S; Chiu, P L; Grace, M; Hanson, J

    1983-02-01

    Thirty-three patients with rheumatoid arthritis had computed tomographic examination of the craniocervical junction. This demonstrated soft tissue features which have not previously been described in published reports. A low attenuation lesion between the odontoid and the transverse ligament shown in 11 patients was considered a premonitory sign of rupture of the transverse ligament or a manifestation of active disease. Computed tomography revealed spinal cord compression in 3 patients and ligamentous changes in the transverse ligament and the alar and spinal ligaments in 26 patients. Erosion of the odontoid was shown in 19 patients and subluxation in 20 patients. No relationship could be found between the clinical signs and symptoms and the radiological abnormalities except in the case of cord compression.

  12. Denoising Message Passing for X-ray Computed Tomography Reconstruction

    CERN Document Server

    Perelli, Alessandro; Can, Ali; Davies, Mike E

    2016-01-01

    X-ray Computed Tomography (CT) reconstruction from sparse number of views is becoming a powerful way to reduce either the radiation dose or the acquisition time in CT systems but still requires a huge computational time. This paper introduces an approximate Bayesian inference framework for CT reconstruction based on a family of denoising approximate message passing (DCT-AMP) algorithms able to improve both the convergence speed and the reconstruction quality. Approximate Message Passing for Compressed Sensing has been extensively analysed for random linear measurements but there are still not clear solutions on how AMP should be modified and how it performs with real world problems. In particular to overcome the convergence issues of DCT-AMP with structured measurement matrices, we propose a disjoint preconditioned version of the algorithm tailored for both the geometric system model and the noise model. In addition the Bayesian DCT-AMP formulation allows to measure how the current estimate is close to the pr...

  13. Computed tomography findings of paracoccidiodomycosis in musculoskeletal system

    Energy Technology Data Exchange (ETDEWEB)

    Lima Junior, Francisco Valtenor Araujo; Savarese, Leonor Garbin; Monsignore, Lucas Moretti; Martinez, Roberto; Nogueira-Barbosa, Marcello Henrique, E-mail: fvaltenor@gmail.com [Universidade de Sao Paulo (FM/USP), Ribeirao Preto, SP (Brazil). Fac. de Medicina

    2015-01-15

    Objective: to evaluate musculoskeletal involvement in paracoccidioidomycosis at computed tomography. Materials and methods: development of a retrospective study based on a review of radiologic and pathologic reports in the institution database. Patients with histopathologically confirmed musculoskeletal paracoccidioidomycosis and submitted to computed tomography were included in the present study. The imaging findings were consensually described by two radiologists. In order to avoid bias in the analysis, one patient with uncountable bone lesions was excluded from the study. Results: a total of seven patients were included in the present study. A total of 18 bone lesions were counted. The study group consisted of 7 patients. A total number of 18 bone lesions were counted. Osteoarticular lesions were the first manifestation of the disease in four patients (57.14%). Bone lesions were multiple in 42.85% of patients. Appendicular and axial skeleton were affected in 85.71% and 42.85% of cases, respectively. Bone involvement was characterized by well-demarcated osteolytic lesions. Marginal osteosclerosis was identified in 72.22% of the lesions, while lamellar periosteal reaction and soft tissue component were present in 5.55% of them. One patient showed multiple small lesions with bone sequestra. Conclusion: paracoccidioidomycosis can be included in the differential diagnosis of either single or multiple osteolytic lesions in young patients even in the absence of a previous diagnosis of pulmonary or visceral paracoccidioidomycosis. (author)

  14. Limited-data computed tomography algorithms for the physical sciences.

    Science.gov (United States)

    Verhoeven, D

    1993-07-10

    Five limited-data computed tomography algorithms are compared. The algorithms used are adapted versions of the algebraic reconstruction technique, the multiplicative algebraic reconstruction technique, the Gerchberg-Papoulis algorithm, a spectral extrapolation algorithm descended from that of Harris [J. Opt. Soc. Am. 54, 931-936 (1964)], and an algorithm based on the singular value decomposition technique. These algorithms were used to reconstruct phantom data with realistic levels of noise from a number of different imaging geometries. The phantoms, the imaging geometries, and the noise were chosen to simulate the conditions encountered in typical computed tomography applications in the physical sciences, and the implementations of the algorithms were optimized for these applications. The multiplicative algebraic reconstruction technique algorithm gave the best results overall; the algebraic reconstruction technique gave the best results for very smooth objects or very noisy (20-dB signal-to-noise ratio) data. My implementations of both of these algorithms incorporate apriori knowledge of the sign of the object, its extent, and its smoothness. The smoothness of the reconstruction is enforced through the use of an appropriate object model (by use of cubic B-spline basis functions and a number of object coefficients appropriate to the object being reconstructed). The average reconstruction error was 1.7% of the maximum phantom value with the multiplicative algebraic reconstruction technique of a phantom with moderate-to-steep gradients by use of data from five viewing angles with a 30-dB signal-to-noise ratio.

  15. Computed tomography of intra - and extramural ethmoid cells: iconographic essay

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Fabricio Guimaraes [McGill University Health Centre (MUHC), Montreal, QC (Canada). Montreal General Hospital; Jovem, Cassio Lemos [Med Imagem, Teresina, PI (Brazil); Moura, Leonardo de Oliveira [Centro de Treinamento em Imagenologia (CETRIM), Joao Pessoa, PB (Brazil)

    2011-09-15

    The development of the paranasal sinuses is an intricate process that begins in the intrauterine life and terminates in early adulthood. Among the paranasal sinuses, the ethmoid cells or labyrinth are probably the most complex structures, being associated with the highest number of normal variants. Variations in the pattern of pneumatization of the ethmoid cells can be divided into intra - and extramural cells. Intramural cells are those which develop within the ethmoid labyrinth. Extramural cells are those that develop isolatedly. Computed tomography is the most useful tool in the evaluation of inflammatory processes of the paranasal sinuses. Computed tomography also plays a relevant role in the preoperative planning as well as in the postoperative follow-up, since it demonstrates exact anatomical details of normal structures with accuracy in the detection of variants. In the present pictorial essay, the authors describe the most common anatomical variants of the ethmoid labyrinth and their relationship with adjacent structures. Endoscopic sinonasal surgery has become increasingly less invasive, requiring more detailed anatomical imaging of this region. (author)

  16. Incidental cardiac findings on computed tomography imaging of the thorax

    Directory of Open Access Journals (Sweden)

    El-Gendi Hossam

    2010-12-01

    Full Text Available Abstract Background Investigation of pulmonary pathology with computed tomography also allows visualisation of the heart and major vessels. We sought to explore whether clinically relevant cardiac pathology could be identified on computed tomography pulmonary angiograms (CTPA requested for the exclusion of pulmonary embolism (PE. 100 consecutive CT contrast-enhanced pulmonary angiograms carried out for exclusion of PE at a single centre were assessed retrospectively by two cardiologists. Findings Evidence of PE was reported in 5% of scans. Incidental cardiac findings included: aortic wall calcification (54%, coronary calcification (46%, cardiomegaly (41%, atrial dilatation (18%, mitral annulus calcification (15%, right ventricular dilatation (11%, aortic dilatation (8% and right ventricular thrombus (1%. Apart from 3 (3% reports describing cardiomegaly, no other cardiac findings were described in radiologists' reports. Other reported pulmonary abnormalities included: lung nodules (14%, lobar collapse/consolidation (8%, pleural effusion (2%, lobar collapse/consolidation (8%, emphysema (6% and pleural calcification (4%. Conclusions CTPAs requested for the exclusion of PE have a high yield of cardiac abnormalities. Although these abnormalities may not have implications for acute clinical management, they may, nevertheless, be important in long-term care.

  17. Use of cone beam computed tomography in periodontology.

    Science.gov (United States)

    Acar, Buket; Kamburoğlu, Kıvanç

    2014-05-28

    Diagnosis of periodontal disease mainly depends on clinical signs and symptoms. However, in the case of bone destruction, radiographs are valuable diagnostic tools as an adjunct to the clinical examination. Two dimensional periapical and panoramic radiographs are routinely used for diagnosing periodontal bone levels. In two dimensional imaging, evaluation of bone craters, lamina dura and periodontal bone level is limited by projection geometry and superpositions of adjacent anatomical structures. Those limitations of 2D radiographs can be eliminated by three-dimensional imaging techniques such as computed tomography. Cone beam computed tomography (CBCT) generates 3D volumetric images and is also commonly used in dentistry. All CBCT units provide axial, coronal and sagittal multi-planar reconstructed images without magnification. Also, panoramic images without distortion and magnification can be generated with curved planar reformation. CBCT displays 3D images that are necessary for the diagnosis of intra bony defects, furcation involvements and buccal/lingual bone destructions. CBCT applications provide obvious benefits in periodontics, however; it should be used only in correct indications considering the necessity and the potential hazards of the examination.

  18. Estimation of feline renal volume using computed tomography and ultrasound.

    Science.gov (United States)

    Tyson, Reid; Logsdon, Stacy A; Werre, Stephen R; Daniel, Gregory B

    2013-01-01

    Renal volume estimation is an important parameter for clinical evaluation of kidneys and research applications. A time efficient, repeatable, and accurate method for volume estimation is required. The purpose of this study was to describe the accuracy of ultrasound and computed tomography (CT) for estimating feline renal volume. Standardized ultrasound and CT scans were acquired for kidneys of 12 cadaver cats, in situ. Ultrasound and CT multiplanar reconstructions were used to record renal length measurements that were then used to calculate volume using the prolate ellipsoid formula for volume estimation. In addition, CT studies were reconstructed at 1 mm, 5 mm, and 1 cm, and transferred to a workstation where the renal volume was calculated using the voxel count method (hand drawn regions of interest). The reference standard kidney volume was then determined ex vivo using water displacement with the Archimedes' principle. Ultrasound measurement of renal length accounted for approximately 87% of the variability in renal volume for the study population. The prolate ellipsoid formula exhibited proportional bias and underestimated renal volume by a median of 18.9%. Computed tomography volume estimates using the voxel count method with hand-traced regions of interest provided the most accurate results, with increasing accuracy for smaller voxel sizes in grossly normal kidneys (-10.1 to 0.6%). Findings from this study supported the use of CT and the voxel count method for estimating feline renal volume in future clinical and research studies.

  19. Simulation of computed tomography dose based on voxel phantom

    Science.gov (United States)

    Liu, Chunyu; Lv, Xiangbo; Li, Zhaojun

    2017-01-01

    Computed Tomography (CT) is one of the preferred and the most valuable imaging tool used in diagnostic radiology, which provides a high-quality cross-sectional image of the body. It still causes higher doses of radiation to patients comparing to the other radiological procedures. The Monte-Carlo method is appropriate for estimation of the radiation dose during the CT examinations. The simulation of the Computed Tomography Dose Index (CTDI) phantom was developed in this paper. Under a similar conditions used in physical measurements, dose profiles were calculated and compared against the measured values that were reported. The results demonstrate a good agreement between the calculated and the measured doses. From different CT exam simulations using the voxel phantom, the highest absorbed dose was recorded for the lung, the brain, the bone surface. A comparison between the different scan type shows that the effective dose for a chest scan is the highest one, whereas the effective dose values during abdomen and pelvis scan are very close, respectively. The lowest effective dose resulted from the head scan. Although, the dose in CT is related to various parameters, such as the tube current, exposure time, beam energy, slice thickness and patient size, this study demonstrates that the MC simulation is a useful tool to accurately estimate the dose delivered to any specific organs for patients undergoing the CT exams and can be also a valuable technique for the design and the optimization of the CT x-ray source.

  20. Proton Computed Tomography: iterative image reconstruction and dose evaluation

    Science.gov (United States)

    Civinini, C.; Bonanno, D.; Brianzi, M.; Carpinelli, M.; Cirrone, G. A. P.; Cuttone, G.; Lo Presti, D.; Maccioni, G.; Pallotta, S.; Randazzo, N.; Scaringella, M.; Romano, F.; Sipala, V.; Talamonti, C.; Vanzi, E.; Bruzzi, M.

    2017-01-01

    Proton Computed Tomography (pCT) is a medical imaging method with a potential for increasing accuracy of treatment planning and patient positioning in hadron therapy. A pCT system based on a Silicon microstrip tracker and a YAG:Ce crystal calorimeter has been developed within the INFN Prima-RDH collaboration. The prototype has been tested with a 175 MeV proton beam at The Svedberg Laboratory (Uppsala, Sweden) with the aim to reconstruct and characterize a tomographic image. Algebraic iterative reconstruction methods (ART), together with the most likely path formalism, have been used to obtain tomographies of an inhomogeneous phantom to eventually extract density and spatial resolutions. These results will be presented and discussed together with an estimation of the average dose delivered to the phantom and the dependence of the image quality on the dose. Due to the heavy computation load required by the algebraic algorithms the reconstruction programs have been implemented to fully exploit the high calculation parallelism of Graphics Processing Units. An extended field of view pCT system is in an advanced construction stage. This apparatus will be able to reconstruct objects of the size of a human head making possible to characterize this pCT approach in a pre-clinical environment.

  1. Quantitative analysis of cholesteatoma using high resolution computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Shigeru; Yamasoba, Tatsuya (Kameda General Hospital, Chiba (Japan)); Iinuma, Toshitaka

    1992-05-01

    Seventy-three cases of adult cholesteatoma, including 52 cases of pars flaccida type cholesteatoma and 21 of pars tensa type cholesteatoma, were examined using high resolution computed tomography, in both axial (lateral semicircular canal plane) and coronal sections (cochlear, vestibular and antral plane). These cases were classified into two subtypes according to the presence of extension of cholesteatoma into the antrum. Sixty cases of chronic otitis media with central perforation (COM) were also examined as controls. Various locations of the middle ear cavity were measured in terms of size in comparison with pars flaccida type cholesteatoma, pars tensa type cholesteatoma and COM. The width of the attic was significantly larger in both pars flaccida type and pars tensa type cholesteatoma than in COM. With pars flaccida type cholesteatoma there was a significantly larger distance between the malleus and lateral wall of the attic than with COM. In contrast, the distance between the malleus and medial wall of the attic was significantly larger with pars tensa type cholesteatoma than with COM. With cholesteatoma extending into the antrum, regardless of the type of cholesteatoma, there were significantly larger distances than with COM at the following sites: the width and height of the aditus ad antrum, and the width, height and anterior-posterior diameter of the antrum. However, these distances were not significantly different between cholesteatoma without extension into the antrum and COM. The hitherto demonstrated qualitative impressions of bone destruction in cholesteatoma were quantitatively verified in detail using high resolution computed tomography. (author).

  2. Glandular dose in breast computed tomography with synchrotron radiation.

    Science.gov (United States)

    Mettivier, G; Fedon, C; Di Lillo, F; Longo, R; Sarno, A; Tromba, G; Russo, P

    2016-01-21

    The purpose of this work is to provide an evaluation of the mean glandular dose (MGD) for breast computed tomography (CT) with synchrotron radiation in an axial scanning configuration with a partial or total organ volume irradiation, for the in vivo program of breast CT ongoing at the ELETTRA facility (Trieste, Italy). A Geant4 Monte Carlo code was implemented, simulating the photon irradiation from a synchrotron radiation source in the energetic range from 8 to 50 keV with 1 keV intervals, to evaluate the MGD. The code was validated with literature data, in terms of mammographic normalized glandular dose coefficients (DgN) and with ad hoc experimental data, in terms of computed tomography dose index (CTDI). Simulated cylindrical phantoms of different sizes (diameter at phantom base 8, 10, 12, 14 or 16 cm, axial length 1.5 times the radius) and glandular fraction by weight (0%, 14.3%, 25%, 50%, 75% and 100%) were implemented into the code. The validation of the code shows an excellent agreement both with previously published work and in terms of DgN and CDTI measurements. The implemented simulations show a dependence of the glandular dose estimate on the vertical dimension of the irradiated zone when a partial organ irradiation was implemented. Specific normalized coefficients for calculating the MGD to the whole breast or to the single irradiated slice were reported.

  3. Computed tomography findings of early abdominal postoperative complications

    Energy Technology Data Exchange (ETDEWEB)

    Zissin, R.; Osadchy, A. [Sapir Medical Center, Dept. of Diagnostic Imaging, Kfar Saba (Israel)]. E-mail: zisinrivka@clalit.org.il; Gayer, G. [Assaf Harofe Medical Center, Dept. of Diagnostic Imaging, Zrifin (Israel)

    2007-06-15

    Various surgical approaches are used for different abdominal pathological conditions. Postoperative complications occur not infrequently and vary according to the type of the surgery and the clinical context. Nowadays, multidetector computed tomography (MDCT) provides superb anatomic detail and diagnostic accuracy for various intraabdominal pathological processes, even if clinically unsuspected, and it thus has become an essential diagnostic tool for evaluating postoperative insults. Other advantages of abdominal MDCT include its accessibility and its speed, which allow scanning of uncooperative, marginally stable patients. Computed tomography (CT)-guided percutaneous (PC) drainage of postoperative collections is another advantage of CT. Therefore, although CT requires transportation of a critically ill, postoperative patient, it is recommended in any suspicious clinical setting because several conditions require prompt management and a correct diagnosis is crucial. In assessing a patient for suspected postoperative complications, several points should be taken into consideration, including the relevant clinical and laboratory data, the surgical findings, the type of the surgery, the time elapsed since surgery, and the operative technique (either open laparotomy of laparoscopic procedure). (author)

  4. Computed tomography angiography in patients with active gastrointestinal bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Fatima Regina Silva; D' Ippolito, Giuseppe, E-mail: fatima.rsreis@gmail.com [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina; Cardia, P.P. [Hospital Vera Cruz, Campinas, SP (Brazil)

    2015-11-15

    Gastrointestinal bleeding represents a common medical emergency, with considerable morbidity and mortality rates, and a prompt diagnosis is essential for a better prognosis. In such a context, endoscopy is the main diagnostic tool; however, in cases where the gastrointestinal hemorrhage is massive, the exact bleeding site might go undetected. In addition, a trained professional is not always present to perform the procedure. In an emergency setting, optical colonoscopy presents limitations connected with the absence of bowel preparation, so most of the small bowel cannot be assessed. Scintigraphy cannot accurately demonstrate the anatomic location of the bleeding and is not available at emergency settings. The use of capsule endoscopy is inappropriate in the acute setting, particularly in the emergency department at night, and is a highly expensive method. Digital angiography, despite its high sensitivity, is invasive, presents catheterization-related risks, in addition to its low availability at emergency settings. On the other hand, computed tomography angiography is fast, widely available and minimally invasive, emerging as a promising method in the diagnostic algorithm of these patients, being capable of determining the location and cause of bleeding with high accuracy. Based on a critical literature review and on their own experience, the authors propose a computed tomography angiography protocol to assess the patient with gastrointestinal bleeding. (author)

  5. Breast ultrasound computed tomography using waveform inversion with source encoding

    Science.gov (United States)

    Wang, Kun; Matthews, Thomas; Anis, Fatima; Li, Cuiping; Duric, Neb; Anastasio, Mark A.

    2015-03-01

    Ultrasound computed tomography (USCT) holds great promise for improving the detection and management of breast cancer. Because they are based on the acoustic wave equation, waveform inversion-based reconstruction methods can produce images that possess improved spatial resolution properties over those produced by ray-based methods. However, waveform inversion methods are computationally demanding and have not been applied widely in USCT breast imaging. In this work, source encoding concepts are employed to develop an accelerated USCT reconstruction method that circumvents the large computational burden of conventional waveform inversion methods. This method, referred to as the waveform inversion with source encoding (WISE) method, encodes the measurement data using a random encoding vector and determines an estimate of the speed-of-sound distribution by solving a stochastic optimization problem by use of a stochastic gradient descent algorithm. Computer-simulation studies are conducted to demonstrate the use of the WISE method. Using a single graphics processing unit card, each iteration can be completed within 25 seconds for a 128 × 128 mm2 reconstruction region. The results suggest that the WISE method maintains the high spatial resolution of waveform inversion methods while significantly reducing the computational burden.

  6. Evaluation of external beam hardening filters on image quality of computed tomography and single photon emission computed tomography/computed tomography.

    Science.gov (United States)

    Rana, Nivedita; Rawat, Dinesh; Parmar, Madan; Dhawan, Devinder Kumar; Bhati, Ashok Kumar; Mittal, Bhagwant Rai

    2015-01-01

    This study was undertaken to evaluate the effect of external metal filters on the image quality of computed tomography (CT) and single photon emission computed tomography (SPECT)/CT images. Images of Jaszack phantom filled with water and containing iodine contrast filled syringes were acquired using CT (120 kV, 2.5 mA) component of SPECT/CT system, ensuring fixation of filter on X-ray collimator. Different thickness of filters of Al and Cu (1 mm, 2 mm, 3 mm, and 4 mm) and filter combinations Cu 1 mm, Cu 2 mm, Cu 3 mm each in combination with Al (1 mm, 2 mm, 3 mm, and 4 mm), respectively, were used. All image sets were visually analyzed for streak artifacts and contrast to noise ratio (CNR) was derived. Similar acquisition was done using Philips CT quality control (QC) phantom and CNR were calculated for its lexan, perspex, and teflon inserts. Attenuation corrected SPECT/CT images of Jaszack phantom filled with 444-555 MBq (12-15 mCi) of (99m)Tc were obtained by applying attenuation correction map generated by hardened X-ray beam for different filter combination, on SPECT data. Uniformity, root mean square (rms) and contrast were calculated in all image sets. Less streak artifacts at iodine water interface were observed in images acquired using external filters as compared to those without a filter. CNR for syringes, spheres, and inserts of Philips CT QC phantom was almost similar to Al 2 mm, Al 3 mm, and without the use of filters. CNR decreased with increasing copper thickness and other filter combinations. Uniformity and rms were lower, and value of contrast was higher for SPECT/CT images when CT was acquired with Al 2 mm and 3 mm filter than for images acquired without a filter. The study suggests that for Infinia Hawkeye 4, SPECT/CT system, Al 2 mm, and 3 mm are the optimum filters for improving image quality of SPECT/CT images of Jaszack or Philips CT QC phantom keeping other parameters of CT constant.

  7. Blunt trauma of bone structures of the chest: Computed tomography vs multidetector computed tomography

    Directory of Open Access Journals (Sweden)

    Petrović Kosta

    2013-01-01

    Full Text Available Background/Aim. Computerized tomography (CT, especially multidetector CT (MDCT, has had a revolutionary impact in diagnostic in traumatized patients. The aim of the study was to identify and compare the frequency of injuries to bone structures of the thorax displayed with 5-mm-thick axial CT slices and thin-slice (MDCT examination with the use of 3D reconstructions, primarily multiplanar reformations (MPR. Methods. This prospective study included 61 patients with blunt trauma submitted to CT scan of the thorax as initial assessment. The two experienced radiologists independently and separately described the findings for 5-mmthick axial CT slices (5 mm CT as in monoslice CT examination; MPR and other 3D reconstructions along with thin-slice axial sections which were available in modern MDCT technologies. After describing thin-slice examination in case of disagreement in the findings, the examiners redescribed thinslice examination together which was ultimately considered as a real, true finding. Results. No statistically significant difference in interobserver evaluation of 5 mm CT examination was recorded (p > 0.05. Evaluation of fractures of sternum with 5 mm CT and MDCT showed a statistically significant difference (p < 0.05 in favor of better display of injury by MDCT examination. Conclusion. MDCT is a powerful diagnostic tool that can describe higher number of bone fractures of the chest in traumatized patients compared to 5 mm CT, especially in the region of sternum for which a statistical significance was obtained using MPR. Moreover, the importance of MDCT is also set by easier and more accurate determination of the level of bone injury.

  8. Massively parallel computers for 3D single-photon-emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Butler, C.S.; Miller, M.I. (Washington Univ., St. Louis, MO (United States). Electronic Systems and Signals Research Lab.); Miller, T.R.; Wallis, J.W. (Washington Univ., St. Louis, MO (United States). Edward Mallinckrodt Inst. of Radiology)

    1994-03-01

    Since the introduction of the expectation-maximization (EM) algorithm for generating maximum-likelihood (ML) and maximum a posteriori (MAP) estimates in emission tomography, there have been many investigators applying the ML method. However, almost all of the previous work has been restricted to two-dimensional (2D) reconstructions. The major focus and contribution of this paper is to demonstrate a fully three-dimensional (3D) implementation of the MAP method for single-photon-emission computed tomography (SPECT). The 3D reconstruction exhibits an improvement in resolution when compared to the generation of the series of separate 2D slice reconstructions. (Author).

  9. Is there a role for the use of volumetric cone beam computed tomography in periodontics?

    Science.gov (United States)

    du Bois, A H; Kardachi, B; Bartold, P M

    2012-03-01

    Volumetric computed cone beam tomography offers a number of significant advantages over conventional intraoral and extraoral panoramic radiography, as well as computed tomography. To date, periodontal diagnosis has relied heavily on the assessment of both intraoral radiographs and extraoral panoramic radiographs. With emerging technology in radiology there has been considerable interest in the role that volumetric cone beam computed tomography might play in periodontal diagnostics. This narrative reviews the current evidence and considers whether there is a role for volumetric cone beam computed tomography in periodontics.

  10. Automatic individualized contrast medium dosage during hepatic computed tomography by using computed tomography dose index volume (CTDI{sub vol})

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Anders; Cederlund, Kerstin; Aspelin, Peter; Brismar, Torkel B. [Intervention and Technology at Karolinska Institutet, Department of Clinical Science, Division of Medical Imaging and Technology, Stockholm (Sweden); Karolinska University Hospital in Huddinge, Department of Radiology, Stockholm (Sweden); Bjoerk, Jonas [FoU-centrum Skaane Skaanes Universitetssjukhus i Lund, Lund (Sweden); Nyman, Ulf [University of Lund, Department of Diagnostic Radiology, Lasarettet Trelleborg, Trelleborg (Sweden)

    2014-08-15

    To compare hepatic parenchymal contrast media (CM) enhancement during multi-detector row computed tomography (MDCT) and its correlation with volume pitch-corrected computed tomography dose index (CTDI{sub vol}) and body weight (BW). One hundred patients referred for standard three-phase thoraco-abdominal MDCT examination were enrolled. BW was measured in the CT suite. Forty grams of iodine was administered intravenously (iodixanol 320 mg I/ml at 5 ml/s or iomeprol 400 mg I/ml at 4 ml/s) followed by a 50-ml saline flush. CTDI{sub vol} presented by the CT equipment during the parenchymal examination was recorded. The CM enhancement of the liver was defined as the attenuation HU of the liver parenchyma during the hepatic parenchymal phase minus the attenuation in the native phase. Liver parenchymal enhancement was negatively correlated to both CTDI{sub vol} (r = -0.60) and BW (r = -0.64), but the difference in correlation between those two was not significant. CTDI{sub vol} may replace BW when adjusting CM doses to body size. This makes it potentially feasible to automatically individualize CM dosage by CT. (orig.)

  11. Low Utility of Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography for Detecting Hepatocellular Carcinoma in Patients Before Liver Transplantation.

    Science.gov (United States)

    Alotaibi, Faisal; Kabbani, Monther; Abaalkhail, Faisal; Chorley, Alicia; Elbeshbeshy, Hany; Al-Hamoudi, Waleed; Alabbad, Saleh; Boehnert, Markus U; Alsofayan, Mohammad; Al-Kattan, Wael; Ahmed, Baderaldeen; Broering, Dieter; Al Sebayel, Mohamed; Elsiesy, Hussien

    2017-02-01

    Our program routinely used fluorodeoxyglucose-positron emission tomography/computed tomography as part of the liver transplant evaluation of patients with hepatocellular carcinoma. The aim of this study was to evaluate the role of this imaging modality in the pretransplant work-up. This was a retrospective chart review of our liver transplant database from January 2011 to December 2014 for all patients with hepatocellular carcinoma who underwent a liver transplant. Collected data included age, sex, cause of liver disease, imaging modality, fluorodeoxyglucose-positron emission tomography/computed tomography results, explant tissue analysis, type of transplant, and transplant outcome. During the study period, 275 liver transplants were performed. Fifty-three patients had hepatocellular carcinoma; 41 underwent fluorodeoxyglucose-positron emission tomography/computed tomography. Twenty-nine patients underwent living-donor liver transplant, and 12 patients underwent deceased-donor liver transplant. One of the 41 patients with negative FDG-imaging results had no evidence of hepatocellular carcinoma in the explant and was excluded from the study. The patients' average age was 58 years (range, 22-72 y), and 28 patients were men. The cause of liver disease was hepatitis C virus in 24 patients, cryptogenic cirrhosis in 12 patients, and hepatitis B virus in 5 patients. One patient had no hepatocellular carcinoma on explants and was excluded from the study. Twenty-five patients had hepatocellular carcinoma that met the Milan criteria, 7 were within the UCSF (University of California, San Francisco) criteria, and 8 exceeded the UCSF criteria. Of the 40 patients, 11 had positive fluorodeoxyglucose-positron emission tomography/computed tomography results (27.5%) with evidence of hepatocellular carcinoma in the explant; the remaining 29 patients (72.5%) had negative results. The fluorodeoxyglucose-positron emission tomography/computed tomography results were positive in 16% (4 of

  12. Coronary Artery Stent Evaluation Using a Vascular Model at 64-Detector Row CT: Comparison between Prospective and Retrospective ECG-Gated Axial Scans

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Shigeru; Furui, Shigeru; Kaminaga, Tatsuro; Miyazawa, Akiyoshi; Ueno, Yasunari; Konno, Kumiko [Teikyo University School of Medicine, Tokyo (Japan); Kuwahara, Sadatoshi; Mehta, Dhruv [Philips Electronics Japan, Ltd. Medical Systems, Tokyo (Japan)

    2009-06-15

    We wanted to evaluate the performance of prospective electrocardiogram (ECG)-gated axial scans for assessing coronary stents as compared with retrospective ECG-gated helical scans. As for a vascular model of the coronary artery, a tube of approximately 2.5-mm inner diameter was adopted and as for stents, three (Bx-Velocity, Express2, and Micro Driver) different kinds of stents were inserted into the tube. Both patent and stenotic models of coronary artery were made by instillating different attenuation (396 vs. 79 Hounsfield unit [HU]) of contrast medium within the tube in tube model. The models were scanned with two types of scan methods with a simulated ECG of 60 beats per minute and using display field of views (FOVs) of 9 and 18 cm. We evaluated the in-stent stenosis visually, and we measured the attenuation values and the diameter of the patent stent lumen. The visualization of the stent lumen of the vascular models was improved with using the prospective ECG-gated axial scans and a 9-cm FOV. The inner diameters of the vascular models were underestimated with mean measurement errors of -1.10 to -1.36 mm. The measurement errors were smaller with using the prospective ECG-gated axial scans (Bx-Velocity and Express2, p < 0.0001; Micro Driver, p = 0.0004) and a 9-cm FOV (all stents: p < 0.0001), as compared with the other conditions, respectively. The luminal attenuation value was overestimated in each condition. For the luminal attenuation measurement, the use of prospective ECG-gated axial scans provided less measurement error compared with the retrospective ECG-gated helical scans (all stents: p < 0.0001), and the use of a 9-cm FOV tended to decrease the measurement error. The visualization of coronary stents is improved by the use of prospective ECG-gated axial scans and using a small FOV with reduced blooming artifacts and increased spatial resolution.

  13. Simulation of emission tomography using grid middleware for distributed computing.

    Science.gov (United States)

    Thomason, M G; Longton, R F; Gregor, J; Smith, G T; Hutson, R K

    2004-09-01

    SimSET is Monte Carlo simulation software for emission tomography. This paper describes a simple but effective scheme for parallel execution of SimSET using NetSolve, a client-server system for distributed computation. NetSolve (version 1.4.1) is "grid middleware" which enables a user (the client) to run specific computations remotely and simultaneously on a grid of networked computers (the servers). Since the servers do not have to be identical machines, computation may take place in a heterogeneous environment. To take advantage of diversity in machines and their workloads, a client-side scheduler was implemented for the Monte Carlo simulation. The scheduler partitions the total decay events by taking into account the inherent compute-speeds and recent average workloads, i.e., the scheduler assigns more decay events to processors expected to give faster service and fewer decay events to those expected to give slower service. When compute-speeds and sustained workloads are taken into account, the speed-up is essentially linear in the number of equivalent "maximum-service" processors. One modification in the SimSET code (version 2.6.2.3) was made to ensure that the total number of decay events specified by the user is maintained in the distributed simulation. No other modifications in the standard SimSET code were made. Each processor runs complete SimSET code for its assignment of decay events, independently of others running simultaneously. Empirical results are reported for simulation of a clinical-quality lung perfusion study.

  14. Computed tomography image reconstruction from only two projections

    CERN Document Server

    Mohammad-Djafari, Ali

    2007-01-01

    English: This paper concerns the image reconstruction from a few projections in Computed Tomography (CT). The main objective of this paper is to show that the problem is so ill posed that no classical method, such as analytical methods based on inverse Radon transform, nor the algebraic methods such as Least squares (LS) or regularization theory can give satisfactory result. As an example, we consider in detail the case of image reconstruction from two horizontal and vertical projections. We then show how a particular composite Markov modeling and the Bayesian estimation framework can possibly propose satisfactory solutions to the problem. For demonstration and educational purpose a set of Matlab programs are given for a live presentation of the results. ----- French: Ce travail, \\`a but p\\'edagogique, pr\\'esente le probl\\`eme inverse de la reconstruction d'image en tomographie X lorsque le nombre des projections est tr\\`es limit\\'e. voir le texte en Anglais et en Fran\\c{c}ais.

  15. Quantifying the debonding of inclusions through tomography and computational homology.

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Wei-Yang; Johnson, George C. (University of California, Berkeley, Berkeley, CA); Mota, Alejandro; Foulk, James W., III; Jin, Huiqing

    2010-09-01

    This report describes a Laboratory Directed Research and Development (LDRD) project to use of synchrotron-radiation computed tomography (SRCT) data to determine the conditions and mechanisms that lead to void nucleation in rolled alloys. The Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory (LBNL) has provided SRCT data of a few specimens of 7075-T7351 aluminum plate (widely used for aerospace applications) stretched to failure, loaded in directions perpendicular and parallel to the rolling direction. The resolution of SRCT data is 900nm, which allows elucidation of the mechanisms governing void growth and coalescence. This resolution is not fine enough, however, for nucleation. We propose the use statistics and image processing techniques to obtain sub-resolution scale information from these data, and thus determine where in the specimen and when during the loading program nucleation occurs and the mechanisms that lead to it. Quantitative analysis of the tomography data, however, leads to the conclusion that the reconstruction process compromises the information obtained from the scans. Alternate, more powerful reconstruction algorithms are needed to address this problem, but those fall beyond the scope of this project.

  16. Use of Positron Emission Tomography/Computed Tomography in Radiation Treatment Planning for Lung Cancer

    Directory of Open Access Journals (Sweden)

    Kezban Berberoğlu

    2016-06-01

    Full Text Available Radiotherapy (RT plays an important role in the treatment of lung cancer. Accurate diagnosis and staging are crucial in the delivery of RT with curative intent. Target miss can be prevented by accurate determination of tumor contours during RT planning. Currently, tumor contours are determined manually by computed tomography (CT during RT planning. This method leads to differences in delineation of tumor volume between users. Given the change in RT tools and methods due to rapidly developing technology, it is now more significant to accurately delineate the tumor tissue. F18 fluorodeoxyglucose positron emission tomography/CT (F18 FDG PET/CT has been established as an accurate method in correctly staging and detecting tumor dissemination in lung cancer. Since it provides both anatomic and biologic information, F18 FDG PET decreases interuser variability in tumor delineation. For instance, tumor volumes may be decreased as atelectasis and malignant tissue can be more accurately differentiated, as well as better evaluation of benign and malignant lymph nodes given the difference in FDG uptake. Using F18 FDG PET/CT, the radiation dose can be escalated without serious adverse effects in lung cancer. In this study, we evaluated the contribution of F18 FDG PET/CT for RT planning in lung cancer.

  17. Virtual positron emission tomography/computed tomography-bronchoscopy: possibilities, advantages and limitations of clinical application

    Energy Technology Data Exchange (ETDEWEB)

    Seemann, Marcus D. [University of Magdeburg, Department of Radiology and Nuclear Medicine, Magdeburg (Germany); Schaefer, Juergen F. [Eberhard-Karls University, Department of Diagnostic Radiology, Tuebingen (Germany); Englmeier, Karl-Hans [Institute of Medical Informatics, GSF-National Research Center for Environment and Health, Neuherberg (Germany)

    2007-03-15

    The aim of this study was to demonstrate the possibilities, advantages and limitations of virtual bronchoscopy using data sets from positron emission tomography (PET) and computed tomography (CT). Twelve consecutive patients with lung cancer underwent PET/CT. PET was performed with F-18-labelled 2-[fluorine-18]-fluoro-2-deoxy-D-glucose ({sup 18}F-FDG). The tracheobronchial system was segmented with a volume-growing algorithm, using the CT data sets, and visualized with a shaded-surface rendering method. The primary tumours and the lymph node metastases were segmented for virtual CT-bronchoscopy using the CT data set and for virtual PET/CT-bronchoscopy using the PET/CT data set. Virtual CT-bronchoscopy using the low-dose or diagnostic CT facilitates the detection of anatomical/morphological structure changes of the tracheobronchial system. Virtual PET/CT-bronchoscopy was superior to virtual CT-bronchoscopy in the detection of lymph node metastases (P=0.001), because it uses the CT information and the molecular/metabolic information from PET. Virtual PET/CT-bronchoscopy with a transparent colour-coded shaded-surface rendering model is expected to improve the diagnostic accuracy of identification and characterization of malignancies, assessment of tumour staging, differentiation of viable tumour tissue from atelectases and scars, verification of infections, evaluation of therapeutic response and detection of an early stage of recurrence that is not detectable or is misjudged in comparison with virtual CT-bronchoscopy. (orig.)

  18. Small-Animal Imaging Using Clinical Positron Emission Tomography/Computed Tomography and Super-Resolution

    Directory of Open Access Journals (Sweden)

    Frank P. DiFilippo

    2012-05-01

    Full Text Available Considering the high cost of dedicated small-animal positron emission tomography/computed tomography (PET/CT, an acceptable alternative in many situations might be clinical PET/CT. However, spatial resolution and image quality are of concern. The utility of clinical PET/CT for small-animal research and image quality improvements from super-resolution (spatial subsampling were investigated. National Electrical Manufacturers Association (NEMA NU 4 phantom and mouse data were acquired with a clinical PET/CT scanner, as both conventional static and stepped scans. Static scans were reconstructed with and without point spread function (PSF modeling. Stepped images were postprocessed with iterative deconvolution to produce super-resolution images. Image quality was markedly improved using the super-resolution technique, avoiding certain artifacts produced by PSF modeling. The 2 mm rod of the NU 4 phantom was visualized with high contrast, and the major structures of the mouse were well resolved. Although not a perfect substitute for a state-of-the-art small-animal PET/CT scanner, a clinical PET/CT scanner with super-resolution produces acceptable small-animal image quality for many preclinical research studies.

  19. Positron emission tomography/computer tomography in guidance of extrahepatic hepatocellular carcinoma metastasis management

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Hepatocellular carcinoma (HCC) is one of the most common primary cancers in the world. Surgery is the gold standard for treatment of patients with HCC. Recurrence and metastasis are the major obstacles to further improve the prognosis of HCC. Most recurrences are intrahepatic. However, 30% of the recurrences are extrahepatic. The role of resection in intrahepatic recurrences is widely accepted. The role of resection in extrahepatic HCC recurrence and metastasis is not well established. 18F fluorodeoxyglucose (18F-FDG) positron emission tomography/computer tomography (PET/CT) is useful in detecting distant metastasis from a variety of malignancies and shows superior accuracy to conventional imaging modalities in identification of intrahepatic and extrahepatic metastasis. We present one patient with one new isolated omental lymph node metastasis, who had a history of huge HCC resected six years ago. The metastatic focus was identified with 18 F-FDG PET/CT and resected. The follow-up revealed good prognosis with a long-term survival potential after resection of the omental lymphatic metastasis.

  20. Cone beam computed tomography: A boon for maxillofacial imaging

    Directory of Open Access Journals (Sweden)

    Sreenivas Rao Ghali

    2017-01-01

    Full Text Available In day to day practice, the radiographic techniques used individually or in combination suffer from some inherent limits of all planar two-dimensional (2D projections such as magnification, distortion, superimposition, and misrepresentation of anatomic structures. The introduction of cone-beam computed tomography (CBCT, specifically dedicated to imaging the maxillofacial region, heralds a major shift from 2D to three-dimensional (3D approach. It provides a complete 3D view of the maxilla, mandible, teeth, and supporting structures with relatively high resolution allowing a more accurate diagnosis, treatment planning and monitoring, and analysis of outcomes than conventional 2D images, along with low radiation exposure to the patient. CBCT has opened up new vistas for the use of 3D imaging as a diagnostic and treatment planning tool in dentistry. This paper provides an overview of the imaging principles, underlying technology, dental applications, and in particular focuses on the emerging role of CBCT in dentistry.

  1. Lung cancer screening: Computed tomography or chest radiographs?

    Institute of Scientific and Technical Information of China (English)

    Edwin; JR; van; Beek; Saeed; Mirsadraee; John; T; Murchison

    2015-01-01

    Worldwide, lung cancer is the leading cause of mortalitydue to malignancy. The vast majority of cases of lung cancer are smoking related and the most effective way of reducing lung cancer incidence and mortality is by smoking cessation. In the Western world, smoking cessation policies have met with limited success. The other major means of reducing lung cancer deaths is to diagnose cases at an earlier more treatable stage employing screening programmes using chest radiographs or low dose computed tomography. In many countries smoking is still on the increase, and the sheer scale of the problem limits the affordability of such screening programmes. This short review article will evaluate the current evidence and potential areas of research which may benefit policy making across the world.

  2. Survey of patient dose in computed tomography in Syria 2009.

    Science.gov (United States)

    Kharita, M H; Khazzam, S

    2010-09-01

    The radiation doses to patient in computed tomography (CT) in Syria have been investigated and compared with similar studies in different countries. This work surveyed 30 CT scanners from six different manufacturers distributed all over Syria. Some of the results in this paper were part of a project launched by the International Atomic Energy Agency in different regions of the world covering Asia, Africa and Eastern Europe. The dose quantities covered are CT dose index (CTDI(w)), dose-length product (DLP), effective dose (E) and collective dose. It was found that most CTDI(w) and DLP values were similar to the European reference levels and in line with the results of similar surveys in the world. The results were in good agreement with the UNSCEAR Report 2007. This study concluded a recommendation for national diagnostic reference level for the most common CT protocols in Syria. The results can be used as a base for future optimisation studies in the country.

  3. Micro-computed tomography for small animal imaging: Technological details

    Institute of Scientific and Technical Information of China (English)

    Hao Li; Hui Zhang; Zhiwei Tang; Guangshu Hu

    2008-01-01

    The high-resolution micro-computed tomography(micro-CT)system has now become an important tool for biological research.The micro-CT system enables a non-invasive inspection to screen anatomical changes in small animals.The promising advantages include high-spatial resolution,high sensitivity to bone and lung,short scan time and cost-effectiveness.The dose received by the small animal might be a critical concern in the research.In this article,the choice of the components,fundamental physical problems,the image reconstruction algorithm and the representative applications of micro-CT are summarized.Some results from our research group are also presented to show high-resolution images obtained by the micro-CT system.

  4. Experimental determination of the segregation process using computer tomography

    Directory of Open Access Journals (Sweden)

    Konstantin Beckmann

    2016-07-01

    Full Text Available Modelling methods such as DEM and CFD are increasingly used for developing high efficient combine cleaning systems. For this purpose it is necessary to verify the complex segregation and separation processes in the combine cleaning system. One way is to determine the segregation and separation function using 3D computer tomography (CT. This method makes it possible to visualize and analyse the movement behaviour of the components of the mixture during the segregation and separation process as well as the derivation of descriptive process parameters. A mechanically excited miniature test rig was designed and built at the company CLAAS Selbstfahrende Erntemaschinen GmbH to achieve this aim. The investigations were carried out at the Fraunhofer Institute for Integrated Circuits IIS. Through the evaluation of the recorded images the segregation process is described visually. A more detailed analysis enabled the development of segregation and separation function based on the different densities of grain and material other than grain.

  5. Temporal bone trauma and complications: computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Ana Maria Doffemond; Gaiotti, Juliana Oggioni; Couto, Caroline Laurita Batista; Gomes, Natalia Delage; Diniz, Renata Lopes Furletti Caldeira; Motta, Emilia Guerra Pinto Coelho, E-mail: anadoffemond@yahoo.com.br [Hospital Mater Dei, Belo Horizonte, MG (Brazil). Unit of Radiology and Imaging Diagnosis

    2013-03-15

    Most temporal bone fractures result from high-energy blunt head trauma, and are frequently related to other skull fractures or to polytrauma. Fractures and displacements of ossicular chain in the middle ear represent some of the main complications of temporal bone injury, and hence they will be more deeply approached in the present article. Other types of injuries include labyrinthine fractures, dural fistula, facial nerve paralysis and extension into the carotid canal. Computed tomography plays a fundamental role in the initial evaluation of polytrauma patients, as it can help to identify important structural injuries that may lead to severe complications such as sensorineural hearing loss, conductive hearing loss, dizziness and balance dysfunction, perilymphatic fistulas, facial nerve paralysis, vascular injury and others. (author)

  6. Malignant uveal melanoma and similar lesions studied by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Mafee, M.F.; Peyman, G.A.; McKusick, M.A.

    1985-08-01

    Forty-four patients with intraocular disease were studied by computed tomography (CT); in 19 cases malignant uveal melanoma was considered the likely diagnosis. CT proved to be accurate in determining the location and size of uveal melanomas, demonstrating scleral invasion, and differentiating melanoma from choroidal detachment or angioma, toxocariasis, and senile macular degeneration. On CT, uveal melanomas appeared as hyperdense lesions with slight to moderate contrast enhancement. Tumors thinner than 2 mm could not be seen. Using dynamic CT, the authors noted moderate peak amplitude, normal or delayed tissue transit time, and persistently elevated washout phase (downslope), indicating increased permeability as the result of an impaired tumor blood barrier. Histological types of uveal melanoma could not be differentiated on the basis of circulatory patterns. Dynamic CT may be useful in distinguishing uveal melanoma from choroidal hemangioma or hematoma.

  7. [Vascular assessment in stroke codes: role of computed tomography angiography].

    Science.gov (United States)

    Mendigaña Ramos, M; Cabada Giadas, T

    2015-01-01

    Advances in imaging studies for acute ischemic stroke are largely due to the development of new efficacious treatments carried out in the acute phase. Together with computed tomography (CT) perfusion studies, CT angiography facilitates the selection of patients who are likely to benefit from appropriate early treatment. CT angiography plays an important role in the workup for acute ischemic stroke because it makes it possible to confirm vascular occlusion, assess the collateral circulation, and obtain an arterial map that is very useful for planning endovascular treatment. In this review about CT angiography, we discuss the main technical characteristics, emphasizing the usefulness of the technique in making the right diagnosis and improving treatment strategies. Copyright © 2012 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  8. Experimental determination of the segregation process using computer tomography

    Directory of Open Access Journals (Sweden)

    Konstantin Beckmann

    2016-08-01

    Full Text Available Modelling methods such as DEM and CFD are increasingly used for developing high efficient combine cleaning systems. For this purpose it is necessary to verify the complex segregation and separation processes in the combine cleaning system. One way is to determine the segregation and separation function using 3D computer tomography (CT. This method makes it possible to visualize and analyse the movement behaviour of the components of the mixture during the segregation and separation process as well as the derivation of descriptive process parameters. A mechanically excited miniature test rig was designed and built at the company CLAAS Selbstfahrende Erntemaschinen GmbH to achieve this aim. The investigations were carried out at the Fraunhofer Institute for Integrated Circuits IIS. Through the evaluation of the recorded images the segregation process is described visually. A more detailed analysis enabled the development of segregation and separation function based on the different densities of grain and material other than grain.

  9. Dimensional measurement of micro-moulded parts by computed tomography

    DEFF Research Database (Denmark)

    Ontiveros, S.; Yagüe-Fabra, J.A.; Jiménez, R.

    2012-01-01

    Computed tomography (CT) is progressively assuming an important role in metrology applications and great efforts are being made in order to turn it into a reliable and standardized measuring technology. CT is typically used for non-destructive tests, but it is currently becoming very popular...... for dimensional metrology applications due to its strategic advantages such as the capability of performing measurements on both the component's surface and volume, allowing inspection possibilities to otherwise non-accessible internal features. This paper focuses on the dimensional verification of two micro......-injection moulded components, selected from actual industrial productions, using CT metrological tools. For this purpose, several parts have been measured with two different CT machines, and the results have been compared with the measurements obtained by other measuring systems. The experimental work carried out...

  10. Cysticercosis of the brain. The value of computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Almeida-Pinto, J.; Veiga-Pires, J.A.; Stocker, A.; Coelho, T.; Monteiro, L.

    Incidence and radiologic findings of neurocysticercosis were investigated in a series of 23 800 consecutive head examinations using computed tomography (CT). The condition was diagnosed in 168 case (0.7%). The parenchymatous form was the most common presentation (96.3%), while the meningeal form corresponded to only 11.9% of cases. These two forms coexisted in some cases. These findings reversed the knowledge on the condition based on conventional radiography. The different CT appearances in the brain are described and a new radiologic protocol for the CT evaluation of the condition is advocated, which includes a follow-up after a trial cure with Praziquantel in the presence of cysts not associated with suggestive brain calcifications. CT were more sensitive than conventional radiography in the differentiation between dead and living larvae, thus having an impact on the therapeutic management of the patients.

  11. Common findings and pseudolesions at computed tomography colonography: pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Atzingen, Augusto Castelli von [Clinical Radiology, Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil); Tiferes, Dario Ariel; Matsumoto, Carlos Alberto; Nunes, Thiago Franchi; Maia, Marcos Vinicius Alvim Soares [Abdominal Imaging Section, Department of Imaging Diagnosis - Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil); D' Ippolito, Giuseppe, E-mail: giuseppe_dr@uol.com.br [Department of Imaging Diagnosis, Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil)

    2012-05-15

    Computed tomography colonography is a minimally invasive method for screening for polyps and colorectal cancer, with extremely unusual complications, increasingly used in the clinical practice. In the last decade, developments in bowel preparation, imaging, and in the training of investigators have determined a significant increase in the method sensitivity. Images interpretation is accomplished through a combined analysis of two-dimensional source images and several types of three-dimensional renderings, with sensitivity around 96% in the detection of lesions with dimensions equal or greater than 10 mm in size, when analyzed by experienced radiologists. The present pictorial essay includes examples of diseases and pseudolesions most frequently observed in this type of imaging study. The authors present examples of flat and polypoid lesions, benign and malignant lesions, diverticular disease of the colon, among other conditions, as well as pseudolesions, including those related to inappropriate bowel preparation and misinterpretation. (author)

  12. Use and impact of positron computed tomography scanning in epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Mazziotta, J.C.; Engel, J. Jr.

    1984-01-01

    Through the effective combination of instrumentation, tracer kinetic principles, and radiopharmaceuticals, positron computed tomography (PET) allows for the analytic, noninvasive measurement of local tissue physiology in humans. A large number of studies have already been performed in patients with epilepsy using 18F-fluorodeoxyglucose (FDG) to measure local cerebral glucose utilization. In patients with complex partial epilepsy who are candidates for surgery, hypometabolic zones have been seen consistently (70%) in the interictal state. The complex anatomical and pathophysiological investigation of these hypometabolic zones is discussed. Ictal studies of patients with partial seizures have demonstrated a much more variable metabolic pattern which usually consists of hypermetabolism relative to baseline or interictal studies. Generalized epilepsy produced by electroconvulsive shock and petit mal epilepsy have been studied using FDG to estimate glucose metabolism.

  13. Meningitis tuberculosa: Clinical findings and results of cranial computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Trautmann, M.; Loddenkemper, R.; Hoffmann, H.G.

    1982-10-01

    Guided by 9 own observations between 1977 and 1981, new diagnostic facilities in tuberculous meningitis are discussed. For differentiation from viral meningitis, measurement of CSF lactic acid concentration in addition to that of CSF glucose has proved to be of value in recent years. In accordance with the literature, two cases of this series which were examined for CSF lactic acid concentration showed markedly elevated levels of 8,4 rsp. 10,4 mmol/l. In contrast to this, in viral meningitis usually values of less than 3.5 mmol/l are found. Additionally, the presence of hypochlor- and hyponatremia, which could be demonstrated in 6 of our 9 patients, may raise the suspicion of tuberculous etiology. In the series presented, cranial computed tomography was of greatest diagnostic value, enabling the diagnosis of hydrocephalus internus in 5, and basal arachnoiditis in 2 cases.

  14. Three-dimensional computed tomography of the acetabulum

    Energy Technology Data Exchange (ETDEWEB)

    Pozzi Mucelli, R.S.; Muner, G.; Pozzi Mucelli, F.; Pozzi Mucelli, M.; Marotti, F.; Dalla Palma, L.

    1986-08-01

    Acetabular fractures represent a complex variety that are classified in different types. Conventional radiology is often inadequate to demonstrate and classify the fractures. Computed tomography (CT) has already been shown to be superior in this field. A further advantage of CT is represented by the recent availability of three-dimensional (3D) images that are realized from axial CT scans by means of a new software. The Authors report the applications of this new software to the study of the normal acetabulum and in patients with fractures. 3D images allows an effective demonstration of the fracture, its irradiation and the dislocation of bone fragments. The information is contained in one or few images rather than many axial images. Therefore the role of 3D images may be considered complementary to axial CT scans.

  15. Non-diffusing photochromic gel for optical computed tomography phantoms

    Science.gov (United States)

    Jordan, K.

    2013-06-01

    This study examines photochromic response in radiation sensitive hydrogels. Genipin, crosslinked, gelatin gel can support high resolution images because the chromophores do not diffuse. A low power, 633 nm He-Ne laser was used to write lines into the gels by a photobleaching reaction. Optical cone-beam computed tomography (CBCT) scans mapped the high resolution images in 3D with 0.25 mm voxel resolution. A straight line was written into a deformed gel and then readout in its relaxed, initial shape. The curved, photo-bleached line demonstrated deformable 3D dosimetry is possible with this system to the balloon edge. High resolution, photochromic images provide key information for characterizing optical CT scanners and 3D dosimeters. Many, ionizing radiation, dosimeter materials demonstrate either a photochromic or photothermal response, allowing this approach to be widely used in quantitative 3D scanning.

  16. Glasses for 3D ultrasound computer tomography: phase compensation

    Science.gov (United States)

    Zapf, M.; Hopp, T.; Ruiter, N. V.

    2016-03-01

    Ultrasound Computer Tomography (USCT), developed at KIT, is a promising new imaging system for breast cancer diagnosis, and was successfully tested in a pilot study. The 3D USCT II prototype consists of several hundreds of ultrasound (US) transducers on a semi-ellipsoidal aperture. Spherical waves are sequentially emitted by individual transducers and received in parallel by many transducers. Reflectivity volumes are reconstructed by synthetic aperture focusing (SAFT). However, straight forward SAFT imaging leads to blurred images due to system imperfections. We present an extension of a previously proposed approach to enhance the images. This approach includes additional a priori information and system characteristics. Now spatial phase compensation was included. The approach was evaluated with a simulation and clinical data sets. An increase in the image quality was observed and quantitatively measured by SNR and other metrics.

  17. Fossa navicularis magna detection on cone-beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Syed, Ali Z. [Dept. of Oral and Maxillofacial Medicine and Diagnostic Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland(United States); Mupparapu, Mel [Div. of Radiology, University of Pennsylvania School of Dental Medicine, Philadelphia (United States)

    2016-03-15

    Herein, we report and discuss the detection of fossa navicularis magna, a close radiographic anatomic variant of canalis basilaris medianus of the basiocciput, as an incidental finding in cone-beam computed tomography (CBCT) imaging. The CBCT data of the patients in question were referred for the evaluation of implant sites and to rule out pathology in the maxilla and mandible. CBCT analysis showed osseous, notch-like defects on the inferior aspect of the clivus in all four cases. The appearance of fossa navicularis magna varied among the cases. In some, it was completely within the basiocciput and mimicked a small rounded, corticated, lytic defect, whereas it appeared as a notch in others. Fossa navicularis magna is an anatomical variant that occurs on the inferior aspect of the clivus. The pertinent literature on the anatomical variations occurring in this region was reviewed.

  18. Computed tomography of the oropharynx in obstructive sleep apnea

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, S.G.; Gislason, T.; Lindholm, C.E.

    Computed tomography (CT) of the oropharynx was obtained in 32 consecutive adult patients with proven OSAS. An additional 15 patients with the same complaints, but without objective evidence of OSAS, were used as a control group, together with 20 normal subjects. The axial widths of the tongue and the genioglossus and hyoglossus muscles were measured by CT. Both the tongue and genioglossus widths were significantly larger in the OSAS patients than in the two control groups (p < 0.001). The increased tongue width will cause encroachment of the oropharyngeal airway below the level of the soft palate. Thus, CT can be used to measure the tongue size in order to evaluate its predictive value for the outcome of the UPPP procedure.

  19. Computed tomography using broadband Bessel THz beams and phase contrast.

    Science.gov (United States)

    Bitman, Assaf; Goldring, Sharone; Moshe, Inon; Zalevsky, Zeev

    2014-04-01

    We present new results demonstrating the capability of performing computed tomography (CT) using broadband Bessel terahertz (THz) beams. Nondiffractive beams such as these exhibit propagation-invariant lines of focus with an extended depth-of-field compared to conventional Gaussian beams. Using this property, we demonstrate a considerable improvement in the 3D reconstruction image of a synthetic sample through the backprojection algorithm. Only when THz Bessel beams are used, a full reconstruction of the object structure is made. Moreover, we use phase-contrast mechanism which improves the spatial resolution and reconstructed images. Our results highlight the potential in using nondiffractive Bessel beams to significantly improve 3D-image reconstruction of THz CT.

  20. Computed tomography of deep fat masses in multiple symmetrical lipomatosis

    Energy Technology Data Exchange (ETDEWEB)

    Enzi, G.; Biondetti, P.R.; Fiore, D.; Mazzoleni, F.

    1982-07-01

    Deep fat masses were evaluated by computed tomography (CT) in 15 patients with multiple symmetrical lipomatosis. In 4 patients, peritracheal accumulations of fat were observed. In 3 of them, tracheal compression by lipomatous tissue was demonstrated: 2 were asymptomatic and the third severe respiratory insufficiency secondary to blockage of the air was by the vocal cords as the result of recurrent nerve palsy. In 6 patients, lipomatous tissue occupied the potential space between the spina scapulae and the trapezius, supraspinatus, and infraspinatus muscles. In 2, calcification of lipomatous masses was observed. There was no relationship between extension of subcutaneous fat and accumulation at deep sites. CT facilitates early detection of peritracheal lipomatous tissue and is helpful in follow-up when deep fat accumulation is responsible for space-occupying lesions requiring surgery.

  1. Dose reduction with adaptive bolus chasing computed tomography angiography.

    Science.gov (United States)

    Cai, Zhijun; Bai, Er-Wei; Wang, Ge; Sharafuddin, Melhem J; Abada, Hicham T

    2010-01-01

    Computed Tomography (CT) has become an effective diagnosis and evaluating tool in clinical; however, its radiation exposure has drawn great attention as more and more CT scans are performed every year. How to reduce the radiation dose and meanwhile keep the resultant CT images diagnosable becomes an important research topic. In this paper, we propose a dose reduction approach along with the adaptive bolus chasing CT Angiography (CTA) techniques, which are capable of tracking the contrast bolus peak over all the blood vessel segments during the CTA scan. By modulating the tube current (and collimator width) online, we can reduce the total radiation dose and maintain the contrast to noise ratio (CNR) of the blood vessel. Numerical experiments on reference DSA data sets show that by using the proposed dose reduction method, the effective radiation dose can be saved about 39%.

  2. Inspection of a Medieval Wood Sculpture Using Computer Tomography

    Science.gov (United States)

    Kapitany, K.; Somogyi, A.; Barsi, A.

    2016-06-01

    Computer tomography (CT) is an excellent technique for obtaining accurate 3D information about the human body. It allows to visualize the organs, bones and blood vessels, furthermore it enables to diagnose anomalies and diseases. Its spatial reconstruction capability supports other interesting applications, such as inspecting different, even valuable objects like ancient sculptures. Current paper presents a methodology of evaluating CT and video imagery through the example of investigating a wood Madonna with infant Jesus sculpture from the 14th century. The developed techniques extract the outer boundary of the statue, which has been triangulated to derive the surface model. The interior of the sculpture has also been revealed: the iron bolts and rivets as well as the woodworm holes can be mapped. By merging the interior and outer data (geometry and texture) interesting visualizations (perspective views, sections etc.) have been created.

  3. Software innovations in computed tomography for structural heart disease interventions.

    Science.gov (United States)

    Hell, Michaela; Marwan, Mohamed; Gaede, Luise; Achenbach, Stephan

    2016-05-17

    Computed tomography (CT) provides high, isotropic spatial resolution and has become firmly established in pre-procedural imaging for structural heart disease interventions. It allows determination of the exact dimensions of the target structure, provides information regarding the access route and permits identification of fluoroscopic projection angles to provide optimal visualisation for device placement. Several software solutions are available and have been systematically evaluated in the context of transcatheter aortic valve implantation (TAVI). The use of software products to perform automated measurements can be useful, especially when the experience and expertise regarding evaluation of CT in the context of structural heart disease are limited. In scientific studies, software has been demonstrated to provide accurate support for annulus sizing and prosthesis selection, to aid in reliably identifying patients in whom a transfemoral access may be problematic, and to suggest suitable angulations for fluoroscopic imaging to achieve an orthogonal view onto the aortic valve during implantation.

  4. Brain perfusion: computed tomography and magnetic resonance techniques.

    Science.gov (United States)

    Copen, William A; Lev, Michael H; Rapalino, Otto

    2016-01-01

    Cerebral perfusion imaging provides assessment of regional microvascular hemodynamics in the living brain, enabling in vivo measurement of a variety of different hemodynamic parameters. Perfusion imaging techniques that are used in the clinical setting usually rely upon X-ray computed tomography (CT) or magnetic resonance imaging (MRI). This chapter reviews CT- and MRI-based perfusion imaging techniques, with attention to image acquisition, clinically relevant aspects of image postprocessing, and fundamental differences between CT- and MRI-based techniques. Correlations with cerebrovascular physiology and potential clinical applications of perfusion imaging are reviewed, focusing upon the two major classes of neurologic disease in which perfusion imaging is most often performed: primary perfusion disorders (including ischemic stroke, transient ischemic attack, and reperfusion syndrome), and brain tumors. © 2016 Elsevier B.V. All rights reserved.

  5. Quantitative Pulmonary Imaging Using Computed Tomography and Magnetic Resonance Imaging

    Science.gov (United States)

    Washko, George R.; Parraga, Grace; Coxson, Harvey O.

    2011-01-01

    Measurements of lung function, including spirometry and body plethesmography, are easy to perform and are the current clinical standard for assessing disease severity. However, these lung functional techniques do not adequately explain the observed variability in clinical manifestations of disease and offer little insight into the relationship of lung structure and function. Lung imaging and the image based assessment of lung disease has matured to the extent that it is common for clinical, epidemiologic, and genetic investigation to have a component dedicated to image analysis. There are several exciting imaging modalities currently being used for the non-invasive study of lung anatomy and function. In this review we will focus on two of them, x-ray computed tomography and magnetic resonance imaging. Following a brief introduction of each method we detail some of the most recent work being done to characterize smoking-related lung disease and the clinical applications of such knowledge. PMID:22142490

  6. Clinicopathological characteristics and computed tomography features of mucinous gastric carcinoma.

    Science.gov (United States)

    Yan, C; Zhu, Z-G; Yan, M; Zhang, H; Pan, Z-L; Chen, J; Xiang, M; Chen, M-M; Liu, B-Y; Lin, Y-Z

    2011-01-01

    This study investigated the clinicopathological characteristics of mucinous gastric carcinoma (MGC) and assessed whether multidetector-row computed tomography (MDCT) could differentiate MGC from non-mucinous gastric carcinoma (NGC). Clinicopathological data from 542 patients with gastric carcinoma (23 MGC, 519 NGC), who underwent pre-operative MDCT examination and curative or palliative gastrectomy, were analysed. Only seven of the 23 patients with MGC were correctly diagnosed pre-operatively by endoscopic biopsy. The MGC patients had larger tumours, a higher frequency of lymph node metastases, were more likely to have tumours of tumour, node, metastasis stages III and IV, and were less likely to have a curative resection than NGC patients. In addition, five MGC patients had calcifications in the thickened gastric wall. In conclusion, MGC is rare and is detected mostly at an advanced stage. The diagnostic sensitivity of MGC by endoscopic biopsy was relatively low, whereas MDCT was helpful in distinguishing MGC from NGC.

  7. The possibilities of computer tomography in paecilomycosis of lungs

    Directory of Open Access Journals (Sweden)

    Abdusalom Ashurov

    2010-09-01

    Full Text Available We have analyzed computed tomography (CT results of chest in 56 patients with lung injures caused by paecilomycosis fungus at the age from 17 to 59 years. In our investigations, the perverted lung pattern due to pathology of interstitial tissue was observed in 52 (93% patients of 56 (with chronic bronchitis - 100%, exogenous-allergic alveolitis - 93%, recurrent pneumonia - 100% and with bronchial asthma - 80%. Analysis showed that CT provides wide opportunities in visualization of all spectrum of symptoms in lung tissue injury and could allow to increase the accuracy of determining the character and degree of injury, and also it could allow to determine localization and spreading of the pathological process.

  8. Gamma-ray computed tomography to characterize soil surface sealing

    Energy Technology Data Exchange (ETDEWEB)

    Pires, L.F.Luiz F. E-mail: lfpires@cena.usp.br; Macedo, Jose R. de; Souza, Manoel D. de; Bacchi, Osny O.S.; Reichardt, Klaus

    2002-09-01

    The application of sewage sludge as a fertilizer on soils may cause compacted surface layers (surface sealing), which can promote changes on soil physical properties. The objective of this work was to study the use of gamma-ray computed tomography, as a diagnostic tool for the evaluation of this sealing process through the measurement of soil bulk density distribution of the soil surface layer of samples subjected to sewage sludge application. Tomographic images were taken with a first generation tomograph with a resolution of 1 mm. The image analysis opened the possibility to obtain soil bulk density profiles and average soil bulk densities of the surface layer and to detect the presence of soil surface sealing. The sealing crust thickness was estimated to be in the range of 2-4 mm.

  9. Degeneration in dysplastic hips. A computer tomography study

    DEFF Research Database (Denmark)

    Jacobsen, Steffen; Rømer, Lone; Søballe, Kjeld

    2005-01-01

    BACKGROUND: Hip dysplasia is considered pre-osteoarthritic, causing degeneration in young individuals. OBJECTIVE: To determine the pattern of degenerative change in moderate to severely dysplastic hips in young patients. DESIGN AND PATIENTS: One hundred and ninety-three consecutively......-referred younger patients with hip pain believed to be caused by hip dysplasia constituted the study cohort. The average age was 35.5 years (range, 15-61 years). They were examined by close-cut transverse pelvic and knee computed tomography and antero-posterior radiographs (CT). We identified 197 hips...... with moderate to severe dysplasia, and 78 hips with normal morphology in the study cohort, whilst 111 hip joints were borderline dysplastic according to preset definitions. Comparative analyses of anatomy and distribution of degeneration between dysplastic and normal hips in the study cohort were performed...

  10. Initial results of finger imaging using Photoacoustic Computed Tomography

    CERN Document Server

    van Es, Peter; Moens, Hein J Bernelot; Steenbergen, Wiendelt; Manohar, Srirang

    2014-01-01

    We present a photoacoustic computed tomography investigation on a healthy human finger, to image blood vessels with a focus on vascularity across the interphalangeal joints. The cross-sectional images were acquired using an imager specifically developed for this purpose. The images show rich detail of the digital blood vessels with diameters between 100 $\\mu$m and 1.5 mm in various orientations and at various depths. Different vascular layers in the skin including the subpapillary plexus could also be visualized. Acoustic reflections on the finger bone of photoacoustic signals from skin were visible in sequential slice images along the finger except at the location of the joint gaps. Not unexpectedly, the healthy synovial membrane at the joint gaps was not detected due to its small size and normal vascularization. Future research will concentrate on studying digits afflicted with rheumatoid arthritis to detect the inflamed synovium with its heightened vascularization, whose characteristics are potential marke...

  11. Dacryocystography using computed tomography prior to external dacryocystorhinostomy

    Energy Technology Data Exchange (ETDEWEB)

    Takagi, Ikue; Chijiiwa, Taeko [National Kyushu Medical Center, Fukuoka (Japan)

    2002-01-01

    We performed dacryocystography using computed tomography in 47 eyes of 45 patients of chronic dacryocystitis prior to external dacryocystorhinostomy. The radiopaque agent was injected into the lower canaliculus. The findings were useful in estimating the thickness of the bony wall of lacrimal fossa. The ethmoidal sinus was located adjacent and nasal to the lacrimal fossa in 11 eyes (23%). Care was needed in these cases not to create an anastomosis between the lacrimal sac and the ethmoidal sinus. The contrast medium was located in the nasolacrimal duct in 14 eyes (30%), suggesting that the obstruction was located in the lower nasolacrimal duct. Intraoperative irrigation-aspiration appeared to be indicated in these cases. Traumatic bony fracture with hypertrophy was present in one case, suggesting that nasolacrimal obstruction may be induced by facial trauma. (author)

  12. Quality Criteria Implementation for Brain Computed Tomography Examinations

    Energy Technology Data Exchange (ETDEWEB)

    Calzado, A.; Rodriguez, R.; Munoz, A

    1998-07-01

    The main aim of this study was to implement the quality criteria proposed by the European Commission for brain computed tomography (CT) examinations. The proposed criteria were evaluated for 102 brain CT examinations, with a special emphasis on the diagnostic and radiation dose requirements. The examinations were selected at random from brain examinations performed over a period of a month at eight scanners of the CT Pace range. Achievement of image criteria was evaluated by two independent observers. The most important preliminary findings concerning image criteria fulfilment or lack of it and disagreements between observers are presented and discussed. The mean values of the proposed dosimetric quantities are compared to the reference values. The examinations performed with and without injection of a contrast agent are also analysed in relation to dosimetric quantities and criteria fulfilment. (author)

  13. Complicated cholecystitis: the complementary roles of sonography and computed tomography.

    Science.gov (United States)

    Charalel, Resmi A; Jeffrey, R Brooke; Shin, Lewis K

    2011-09-01

    Acute cholecystitis is a common cause of abdominal pain in the Western world. Unless treated promptly, patients with acute cholecystitis may develop complications such as gangrenous, perforated, or emphysematous cholecystitis. Because of the increased morbidity and mortality of complicated cholecystitis, early diagnosis and treatment are essential for optimal patient care. Nevertheless, complicated cholecystitis may pose significant challenges with cross-sectional imaging, including sonography and computed tomography (CT). Interpreting radiologists should be familiar with the spectrum of sonographic findings seen with complicated cholecystitis and as well as understand the complementary role of CT. Worrisome imaging findings for complicated cholecystitis include intraluminal findings (sloughed mucosa, hemorrhage, abnormal gas), gallbladder wall abnormalities (striations, asymmetric wall thickening, abnormal gas, loss of sonoreflectivity and contrast enhancement), and pericholecystic changes (echogenic fat, pericholecystic fluid, abscess formation). Finally, diagnosis of complicated cholecystitis by sonography and CT can guide alternative treatments including minimally invasive percutaneous and endoscopic options.

  14. Application of cone beam computed tomography in facial imaging science

    Institute of Scientific and Technical Information of China (English)

    Zacharias Fourie; Janalt Damstra; Yijin Ren

    2012-01-01

    The use of three-dimensional (3D) methods for facial imaging has increased significantly over the past years.Traditional 2D imaging has gradually being replaced by 3D images in different disciplines,particularly in the fields of orthodontics,maxillofacial surgery,plastic and reconstructive surgery,neurosurgery and forensic sciences.In most cases,3D facial imaging overcomes the limitations of traditional 2D methods and provides the clinician with more accurate information regarding the soft-tissues and the underlying skeleton.The aim of this study was to review the types of imaging methods used for facial imaging.It is important to realize the difference between the types of 3D imaging methods as application and indications thereof may differ.Since 3D cone beam computed tomography (CBCT) imaging will play an increasingly importanl role in orthodontics and orthognathic surgery,special emphasis should be placed on discussing CBCT applications in facial evaluations.

  15. Transcolonic retrograde ureteric catheterization assisted by 3-d computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Snow, T.M.; Olivier, J.; Vigar, M. [Gold Coast Hospital, Southport, QLD (Australia). Department of Radiology; Parnham, A.P. [Gold Coast Hospital, Southport, QLD (Australia). Department of Radiology

    1999-08-01

    A 42-year-old woman had bladder extrophy at birth, treated by ureterocolic anastomosis of her single kidney. She suffered recurrent hyperammonaemia, leading to comas, but refused an ileal conduit. During her most recent coma, it was decided to divert her urine to test whether this would reduce hyperammonaemia: this was accomplished by transcolonic retrograde catheterization of the ureter. This was only possible after computed tomography ureterography to show the ureterocolic anastomosis. Ureterocolic anastomosis is associated with several complications, the best known being hyperchloraemic acidosis and potassium deficiency. There is also a very high incidence of stricture at the anastomosis, both benign and malignant. Hyperammonaemia is less common. It can lead to disturbance of consciousness and seizures. It is caused by reabsorption of ammonia from the colon, exacerbated by the presence of urea-splitting organisms. Copyright (1999) Blackwell Science Pty Ltd 8 refs., 4 figs.

  16. Cholecystocolonic fistula mimicking acute cholecystitis diagnosed unequivocally by computed tomography.

    Science.gov (United States)

    Chick, Jeffrey Forris Beecham; Chauhan, Nikunj Rashmikant; Paulson, Vera Ashley; Adduci, Alexander J

    2013-12-01

    Cholecystocolonic fistula is an uncommon potential complication of cholecystitis found intraoperatively in 0.06-0.14 % of patients undergoing cholecystectomy and 0.1-0.5 % of autopsy series. Although cholecystocolonic fistula is the second most common cholecystoenteric fistula, second only to cholecystoduodenal fistula, it is diagnosed preoperatively in only 7.9 % of patients. Failure to preoperatively diagnose cholecystocolonic fistula places surgeons in precarious positions, as they may be forced to convert a seemingly routine cholecystectomy to a more sophisticated procedure coupled with adhesiolysis, colonic suturing, or colonic resection. We report a young patient who presented to the emergency department with complaints indicative of acute cholecystitis; however, preoperative ultrasound was suggestive of a cholecystoenteric fistula. Computed tomography and pathology were pathognomonic with clear visualization of the cholecystocolonic fistulous tract.

  17. Building a 3D Computed Tomography Scanner From Surplus Parts.

    Science.gov (United States)

    Haidekker, Mark A

    2014-01-01

    Computed tomography (CT) scanners are expensive imaging devices, often out of reach for small research groups. Designing and building a CT scanner from modular components is possible, and this article demonstrates that realization of a CT scanner from components is surprisingly easy. However, the high costs of a modular X-ray source and detector limit the overall cost savings. In this article, the possibility of building a CT scanner with available surplus X-ray parts is discussed, and a practical device is described that incurred costs of less than $16,000. The image quality of this device is comparable with commercial devices. The disadvantage is that design constraints imposed by the available components lead to slow scan speeds and a resolution of 0.5 mm. Despite these limitations, a device such as this is attractive for imaging studies in the biological and biomedical sciences, as well as for advancing CT technology itself.

  18. Cone beam computed tomography: A new vision in dentistry

    Directory of Open Access Journals (Sweden)

    Manas Gupta

    2015-01-01

    Full Text Available Cone beam computed tomography (CBCT is a developing imaging technique designed to provide relatively low-dose high-spatial-resolution visualization of high-contrast structures in the head and neck and other anatomic areas. It is a vital content of a dental patient's record. A literature review demonstrated that CBCT has been utilized for oral diagnosis, oral and maxillofacial surgery, endodontics, implantology, orthodontics; temporomandibular joint dysfunction, periodontics, and restorative and forensic dentistry. Recently, higher emphasis has been placed on the CBCT expertise, the three-dimensional (3D images, and virtual models. This literature review showed that the different indications for CBCT are governed by the needs of the specific dental discipline and the type of procedure performed.

  19. Computed tomography of the retroperitoneum in patients with femoral neuropathy.

    Science.gov (United States)

    Eustace, S; McCarthy, C; O'Byrne, J; Breatnach, E; Fitzgerald, E

    1994-08-01

    The authors illustrate the value of computed tomography (CT) of the retroperitoneum in patients presenting with femoral nerve signs. They describe 28 such patients, examined at a tertiary-care hospital between June 1990 and January 1993, in whom CT of the retroperitoneum contributed significantly to the diagnosis. The patients, 19 males and 9 females, ranged in age from 11 to 81 years. CT showed disease of the psoas compartment in 17 cases; the condition was due to a malignant lesion in 9 cases and was secondary to infection in 5 and to other causes in 3. Disease of the iliacus compartment was shown in 11 cases; it was due to a malignant lesion in 6 cases and was secondary to hemorrhage in 2, to infection in 1 and to a bursa in 1. The diagnostic features of the diseases encountered are discussed, and the importance of performing CT early is stressed.

  20. Cone Beam Computed Tomography Evaluation of Inverted Mesiodentes.

    Science.gov (United States)

    Al-Sehaibany, Fares S; Marzouk, Hazem M; Salama, Fouad S

    2016-01-01

    A mesiodens is the most common type of supernumerary teeth. The purpose of this report is to present a rare occurrence of non-syndromic impacted inverted mesiodentes in an 8.5-year-old boy who presented with a chief complaint of delayed eruption of his permanent maxillary left central incisor. Occlusal and panoramic radiographs, as well as cone beam computed tomography (CBCT) with a three-dimensional (3-D) reconstruction image, confirmed that one supernumerary tooth had perforated the nasal fossa floor and the other was in close approximation to the to the same site. Surgical removal of both mesiodentes was indicated. Radiographic evidence of complete healing was observed 12 months following surgical removal. The use of CBCT with a 3-D reconstruction image as a tool in diagnosis and evaluation of healing after surgical removal is recommended.

  1. PET/Computed Tomography Scanning and Precision Medicine: Esophageal Cancer.

    Science.gov (United States)

    Goel, Reema; Subramaniam, Rathan M; Wachsmann, Jason W

    2017-10-01

    Esophageal cancer commonly has a poor prognosis, which requires an accurate diagnosis and early treatment to improve outcome. Other modalities for staging, such as endoscopic ultrasound imaging and computed tomography (CT) scans, have a role in diagnosis and staging. However, PET with fluorine-18 fluoro-2-deoxy-d-glucose/CT (FDG PET/CT) scanning allows for improved detection of distant metastatic disease and can help to prevent unnecessary interventions that would increase morbidity. FDG PET/CT scanning is valuable in the neoadjuvant chemotherapy assessment and predicting survival outcomes subsequent to surgery. FDG PET/CT scanning detects recurrent disease and metastases in follow-up. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Computed tomography dose optimisation in cystic fibrosis: A review.

    LENUS (Irish Health Repository)

    Ferris, Helena

    2016-04-28

    Cystic fibrosis (CF) is the most common autosomal recessive disease of the Caucasian population worldwide, with respiratory disease remaining the most relevant source of morbidity and mortality. Computed tomography (CT) is frequently used for monitoring disease complications and progression. Over the last fifteen years there has been a six-fold increase in the use of CT, which has lead to a growing concern in relation to cumulative radiation exposure. The challenge to the medical profession is to identify dose reduction strategies that meet acceptable image quality, but fulfil the requirements of a diagnostic quality CT. Dose-optimisation, particularly in CT, is essential as it reduces the chances of patients receiving cumulative radiation doses in excess of 100 mSv, a dose deemed significant by the United Nations Scientific Committee on the Effects of Atomic Radiation. This review article explores the current trends in imaging in CF with particular emphasis on new developments in dose optimisation.

  3. Recent Developments in Computed Tomography for Urolithiasis: Diagnosis and Characterization

    Directory of Open Access Journals (Sweden)

    P. D. Mc Laughlin

    2012-01-01

    Full Text Available Objective. To critically evaluate the current literature in an effort to establish the current role of radiologic imaging, advances in computed tomography (CT and standard film radiography in the diagnosis, and characterization of urinary tract calculi. Conclusion. CT has a valuable role when utilized prudently during surveillance of patients following endourological therapy. In this paper, we outline the basic principles relating to the effects of exposure to ionizing radiation as a result of CT scanning. We discuss the current developments in low-dose CT technology, which have resulted in significant reductions in CT radiation doses (to approximately one-third of what they were a decade ago while preserving image quality. Finally, we will discuss an important recent development now commercially available on the latest generation of CT scanners, namely, dual energy imaging, which is showing promise in urinary tract imaging as a means of characterizing the composition of urinary tract calculi.

  4. Basal ganglia calcification on computed tomography in systemic lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Nagaoka, Shohei; Tani, Kenji; Ishigatsubo, Yoshiaki and others

    1988-09-01

    The development of basal ganglia calcification was studied in 85 patients with systemic lupus erythematosus (SLE) by computed tomography (CT). Bilateral calcification of the basal ganglia was found to occur in 5 patients (5.9 %) with SLE, but was not seen in patients with rheumatoid arthritis and progressive systemic sclerosis. All were female with a mean age of 42 years (range 29 - 49). The patients with calcification of the basal ganglia had neurological symptoms, such as psychiatric problems (3 cases), grand mal seizures (1 case), CSF abnormalities (2 cases), and EEG changes (4 cases). There were significantly higher incidences of alopecia, cutaneous vasculitis, leukopenia, and thrombocytopenia in the group with calcifications than those in the group with normal CT findings. Circulating immune complexes were detected and LE tests were positive in 2 patients. Endocrinological examination showed no abnormality in any. We suggest that basal ganglia calcification in SLE might be related to cerebral vasculitis.

  5. Absorbed and effective dose from spiral and computed tomography for the dental implant planning

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Beong Hee; Han, Won Jeong; Kim, Eun Kyung [Dankook Univ. School of Dentistry, Seoul (Korea, Republic of)

    2001-09-15

    To evaluate the absorbed and effective doses of spiral and computed tomography for the dental implant planning. For radiographic projection. TLD chips were placed in 22 sites of humanoid phantom to record the exposure to skin and the mean absorbed dose to bone marrow, thyroid, pituitary, parotid and submandibular glands and nesophages. Effective dose was calculated, using the method suggested by Frederiksen at al.. Patient situations of a single tooth gap in upper and lower midline region, edentulous maxilla and mandible were simulated for spiral tomography. 35 axial slices (maxilla) and 40 axial slices (mandible) with low and standard dose setting were used for computed tomography. All the radiographic procedures were repeated three times. The mean effective dose in case of maxilla was 0.865 mSv, 0.452 mSv, 0.136 mSv and 0.025 mSv, in spiral tomography of complete edentulous maxilla, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). That in case of mandible was 0.614 mSv, 0.448 mSv, 0.137 mSv and 0.036 mSv, in spiral tomography of complete edentulous mandible, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). Based on these results, it can be concluded that low mAs computed tomography is recommended instead of spiral tomography for the complete edentulous maxilla and mandible dental implant treatment planning.

  6. Effect of object location on the density measurement in cone-beam computed tomography versus multislice computed tomography.

    Science.gov (United States)

    Eskandarloo, Amir; Abdinian, Mehrdad; Salemi, Fatemeh; Hashemzadeh, Zahra; Safaei, Mehran

    2012-12-01

    Bone density measurement in a radiographic view is a valuable method for evaluating the density of bone quality before performing some dental procedures such as, dental implant placements. It seems that Cone-Beam Computed Tomography (CBCT) can be used as a diagnostic tool for evaluating the density of the bone, prior to any treatment, as the reported radiation dose in this method is minimal. The aim of this study is to investigate the effect of object location on the density measurement in CBCT versus Multislice computed tomography (CT). In an experimental study, three samples with similar dimensions, but different compositions, different densities (Polyethylene, Polyamide, Polyvinyl Chloride), and three bone pieces of different parts of the mandibular bone were imaged in three different positions by CBCT and Multislice CT sets. The average density value was computed for each sample in each position. Then the data obtained from each CBCT was converted to a Hounsfield unit and evaluated using a single variable T analysis. A P value <0.05 was considered to be significant. The density in a Multislice CT is stable in the form of a Hounsfield Number, but this density is variable in the images acquired through CBCT, and the change in the position results in significant changes in the density. In this study, a statistically significant difference (P value = 0.000) has been observed for the position of the sample and its density in CBCT in comparison to Multislice CT. Density values in CBCT are not real because they are affected by the position of the object in the machine.

  7. Quantification and clinical relevance of head motion during computed tomography.

    Science.gov (United States)

    Wagner, Arne; Schicho, Kurt; Kainberger, Franz; Birkfellner, Wolfgang; Grampp, Stephan; Ewers, Rolf

    2003-11-01

    To quantify the 3-dimensional translation and rotation components of head motion during computed tomography and to analyze the influence of such motion on perceptible artifacts and distortion of volume image data sets. Using high-precision optoelectronic motion-capture technology, changes in patient head position during axial CT scanning were registered in 20 cases and 2 phantoms with a spatial relative resolution better than 0.003 cm. Statistical analysis was performed on a base of 6-dimensional measurement-vectors, each with 3 translation and 3 rotation values. Because of the recording frequency of the tracking system, more than 80000 values were included in a statistical analysis. All 20 patients had head motion during the CT scanning, with only 4 of 20 patients showing perceptible motion artifacts. The frequency, the extent, and the direction of the movements did not correlate with either the observations made by the radiologic staff or with the patient's subjective estimation of comfort. Translation movements of the head during CT accounted for a maximum of 0.5 cm and rotations of more than 2 degrees without perceptible motion artifacts. The extent of positional changes of the head was found to correlate with the duration of scanning (Pearson's correlation coefficient: 0.647 for translation shifts, 0.453 for rotation shifts). The mean direction of head motion could be characterized predominantly as a rotation around the longitudinal axis of the body (xy plane) at a significance level of 0.01. Computed tomography evaluations of the head performed without rigid fixation suffer a spatial distortion of the volume image data sets, caused by interimage motion. The absence of motion artifacts is not correlated with the absence of motion.

  8. Multiscale and multimodality computed tomography for cortical bone analysis

    Science.gov (United States)

    Ostertag, A.; Peyrin, F.; Gouttenoire, P. J.; Laredo, J. D.; DeVernejoul, M. C.; Cohen Solal, M.; Chappard, C.

    2016-12-01

    In clinical studies, high resolution peripheral quantitative computed tomography (HR-pQCT) is used to separately evaluate cortical bone and trabecular bone with an isotropic voxel of 82 µm3, and typical cortical parameters are cortical density (D.comp), thickness (Ct.Th), and porosity (Ct.Po). In vitro, micro-computed tomography (micro-CT) is used to explore the internal cortical bone micro-structure with isotropic voxels and high resolution synchrotron radiation (SR); micro-CT is considered the ‘gold standard’. In 16 tibias and 8 femurs, HR-pQCT measurements were compared to conventional micro-CT measurements. To test modality effects, conventional micro-CT measurements were compared to SR micro-CT measurements at 7.5 µm3 SR micro-CT measurements were also tested at different voxel sizes for the femurs, specifically, 7.5 µm3 versus 2.8 µm3. D.comp (r  =  -0.88, p  images provided consistent results compared to those obtained using conventional micro-CT at the distal tibia. D.comp was highly correlated to Po.V/TV because it considers both the micro-porosity (Haversian systems) and macro-porosity (resorption lacunae) of cortical bone. The complexity of canal organization, (including shape, connectivity, and surface) are not fully considered in conventional micro-CT in relation to beam hardening and cone beam reconstruction artifacts. With the exception of Po.V/TV measurements, morphological and topological measurements depend on the characteristics of the x-ray beam, and to a lesser extent, on image resolution.

  9. Sex estimation from sternal measurements using multidetector computed tomography.

    Science.gov (United States)

    Ekizoglu, Oguzhan; Hocaoglu, Elif; Inci, Ercan; Bilgili, Mustafa Gokhan; Solmaz, Dilek; Erdil, Irem; Can, Ismail Ozgur

    2014-12-01

    We aimed to show the utility and reliability of sternal morphometric analysis for sex estimation.Sex estimation is a very important step in forensic identification. Skeletal surveys are main methods for sex estimation studies. Morphometric analysis of sternum may provide high accuracy rated data in sex discrimination. In this study, morphometric analysis of sternum was evaluated in 1 mm chest computed tomography scans for sex estimation. Four hundred forty 3 subjects (202 female, 241 male, mean age: 44 ± 8.1 [distribution: 30-60 year old]) were included the study. Manubrium length (ML), mesosternum length (2L), Sternebra 1 (S1W), and Sternebra 3 (S3W) width were measured and also sternal index (SI) was calculated. Differences between genders were evaluated by student t-test. Predictive factors of sex were determined by discrimination analysis and receiver operating characteristic (ROC) analysis. Male sternal measurement values are significantly higher than females (P < 0.001) while SI is significantly low in males (P < 0.001). In discrimination analysis, MSL has high accuracy rate with 80.2% in females and 80.9% in males. MSL also has the best sensitivity (75.9%) and specificity (87.6%) values. Accuracy rates were above 80% in 3 stepwise discrimination analysis for both sexes. Stepwise 1 (ML, MSL, S1W, S3W) has the highest accuracy rate in stepwise discrimination analysis with 86.1% in females and 83.8% in males. Our study showed that morphometric computed tomography analysis of sternum might provide important information for sex estimation.

  10. Evaluation of computer tomography in cerebro-vascular disease (Strokes)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Sik; Baek, Seung Yon; Rhee, Chung Sik; Kim, Hee Seup [Ewha Womans University College of Medicine, Seoul (Korea, Republic of)

    1984-06-15

    Most of cerebrovascular disease are composed of vascular occulusive changes and hemorrhage. Now a day, the computed tomography is the best way for evaluation of cerebrovascular disease including detection of nature, location, and associated changes. This study includes evaluation of computed tomography of 70 patients with cerebrovascular disease during the period of 10 months from April. 1983 to Feb. 1984 in Department of Radiology, Ewha Womans University Hospital. The results were as follows: 1. Age distribution of the total 70 patients was broad ranging from 25 years to 79 years. 78.6% of patients were over the age of 50. The male and female sex ratio was 1.4:1. 2. 4 out of 70 patients were normal and 66 patients revealed abnormal on C.T. findings; those were intracranial hemorrhage (28 patients), cerebral infarction (34 patients) and brain atrophy (4 patients). 3. In cases of cerebral infarction, the cerebral hemisphere was most common site of lesion (28 cases), and next was basal ganglia (2 cases). Most of the infarcts in cerebral hemisphere were located in the parietal and temporal lobes. 4. In cases of intracranial hemorrhage, the basal ganglia was most common site of lesion (15 cases). The next common site was cerebral hemisphere (9 cases). 6 patients of all intracranial hemorrhage were combined with intraventricular hemorrhage. Ratio of right and left was 2:3. 5. In patients with motor weakness or hemiparesis, more common findings on CT scan were cerebral infarction. In case with hemiplegia, more common CT findings were intracerebral hemorrhage. 6. Of the 40 cases thought to be cerebral infarction initially by clinical findings and spinal tap. 8 cases (20.0%) were proved to be cerebral hemorrhage by the CT scan. However, of the 22 cases thought to be cerebral hemorrhage, initially, only two cases (9.0%) were cerebral infarction.

  11. Actinomycosis involving the liver. Computed tomography/ultrasound correlation.

    Science.gov (United States)

    Sheth, S; Fishman, E K; Sanders, R

    1987-06-01

    The clinical profile of pelvic actinomycosis, which is being recognized with increased frequency in IUD users, can be misleading in such patients and lead to dangerous delays in diagnosis. The authors present a case in which an IUD user initially sought medical attention for multiple liver abscesses secondary to spread from unsuspected ovarian actinomycosis. The 43-year-old patient, who was admitted with right upper quadrant pain and fever, had a 15-year history of IUD use, although the device had been removed 1 year prior to admission for apparent infection in the left ovary. Ultrasound revealed mixed cystic and solid liver lesions as well as a complex subcapsular fluid collection. A solid left adnexal mass was demonstrated in the pelvis. Computed tomography scan indicated extension of 1 of the complex cystic liver lesions through the liver capsule and into the abdominal wall. Needle aspirations of the liver lesions yielded thick pus that was later identified as Actinomyces israelii. Actinomycosis was evident in the ovarian lesion. Colonization of the vagina and uterus by actinomycosis has been reported by 1.6-5.3% of IUD users, and the risk appears to increase when the same IUD is used for a prolonged time period. In this case, neither the computed tomography scan nor ultrasound suggested an inflammatory process of the left ovary. Aspiration of a liver lesion under ultrasound guidance was necessary for the correct diagnosis. Since actinomycosis has the potential to spread to extrapelvic organs such as the peritoneum, liver, and brain, early diagnosis is essential.

  12. Artifacts in computed tomography scanning of moving objects.

    Science.gov (United States)

    Chen, George T Y; Kung, Jong H; Beaudette, Kevin P

    2004-01-01

    Target volumes in the thorax and abdomen are commonly computed tomography (CT) scanned during light respiration. In this article, we analyze the distortions introduced in helical scanning of moving objects. Objects of known geometry are placed on a moving sled and scanned in a multirow helical CT scanner. The motion of the sled approximates the magnitude and velocity of organ movement in patients during light respiration (amplitude 1 cm, period 4 seconds). Scans of the phantom are obtained in high speed mode at incremental phases of respiration, and the resulting images are compared with scans obtained when the phantom is static. Computer simulations of the scan process are also performed to interpret the results and extend the analysis to a greater range of parameters in scanning, motion, and object size. Resulting scans show that spherical test objects can be shortened by as much as 2 cm or twice the periodic motion amplitude. Object shape was significantly distorted, and the geometric center of the object was displaced by as much as +/-0.8 cm. Computer simulation results qualitatively agree with the experimentally observed phantom images. These simulations predict that the effect is clearly observable even if the amplitude is decreased to 0.5 cm. Implications of scanning moving objects on treatment planning are discussed.

  13. 99mTc-methylene diphosphonate single-photon emission computed tomography/computed tomography improves the diagnostic accuracy of osteoid osteoma

    Science.gov (United States)

    Squier, Samuel Brian; Lewis, Jacob Ian; Accurso, Joseph Matthew; Jain, Manoj Kumar

    2016-01-01

    We present a case of a 17-year-old football player who had previously received multiple facet joint injections for presumed secondary osteoarthritis. 99mTc-methylene diphosphonate single-photon emission computed tomography/computed tomography imaging of the cervical spine demonstrated focal increased radiopharmaceutical activity in the right C2 lamina, which was associated with an osteolytic lesion with a central irregular sclerotic nidus. Surgical pathology confirmed an osteoid osteoma. PMID:27833319

  14. Time-Domain Terahertz Computed Axial Tomography NDE System

    Science.gov (United States)

    Zimdars, David

    2012-01-01

    NASA has identified the need for advanced non-destructive evaluation (NDE) methods to characterize aging and durability in aircraft materials to improve the safety of the nation's airline fleet. 3D THz tomography can play a major role in detection and characterization of flaws and degradation in aircraft materials, including Kevlar-based composites and Kevlar and Zylon fabric covers for soft-shell fan containment where aging and durability issues are critical. A prototype computed tomography (CT) time-domain (TD) THz imaging system has been used to generate 3D images of several test objects including a TUFI tile (a thermal protection system tile used on the Space Shuttle and possibly the Orion or similar capsules). This TUFI tile had simulated impact damage that was located and the depth of damage determined. The CT motion control gan try was designed and constructed, and then integrated with a T-Ray 4000 control unit and motion controller to create a complete CT TD-THz imaging system prototype. A data collection software script was developed that takes multiple z-axis slices in sequence and saves the data for batch processing. The data collection software was integrated with the ability to batch process the slice data with the CT TD-THz image reconstruction software. The time required to take a single CT slice was decreased from six minutes to approximately one minute by replacing the 320 ps, 100-Hz waveform acquisition system with an 80 ps, 1,000-Hz waveform acquisition system. The TD-THZ computed tomography system was built from pre-existing commercial off-the-shelf subsystems. A CT motion control gantry was constructed from COTS components that can handle larger samples. The motion control gantry allows inspection of sample sizes of up to approximately one cubic foot (.0.03 cubic meters). The system reduced to practice a CT-TDTHz system incorporating a COTS 80- ps/l-kHz waveform scanner. The incorporation of this scanner in the system allows acquisition of 3D

  15. Enhancement of photoacoustic tomography in the tissue with speed-of-sound variance using ultrasound computed tomography

    Institute of Scientific and Technical Information of China (English)

    程任翔; 陶超; 刘晓峻

    2015-01-01

    The speed-of-sound variance will decrease the imaging quality of photoacoustic tomography in acoustically inhomo-geneous tissue. In this study, ultrasound computed tomography is combined with photoacoustic tomography to enhance the photoacoustic tomography in this situation. The speed-of-sound information is recovered by ultrasound computed to-mography. Then, an improved delay-and-sum method is used to reconstruct the image from the photoacoustic signals. The simulation results validate that the proposed method can obtain a better photoacoustic tomography than the conventional method when the speed-of-sound variance is increased. In addition, the influences of the speed-of-sound variance and the fan-angle on the image quality are quantitatively explored to optimize the image scheme. The proposed method has a good performance even when the speed-of-sound variance reaches 14.2%. Furthermore, an optimized fan angle is revealed, which can keep the good image quality with a low cost of hardware. This study has a potential value in extending the biomedical application of photoacoustic tomography.

  16. Centre of Rotation Determination Using Projection Data in X-ray Micro Computed Tomography

    OpenAIRE

    Olander, Birger

    1994-01-01

    There are several methods available to determine the Centre Of Rotation, COR, and align detectors and X-ray focus to COR in X-ray computed tomography. Some methods use narrow rods/needles or specially made alignment objects or phantoms. In X-ray Micro Computed Tomography (or Computerized Micro Tomography), μCT (CMT), methods using sample projection data for COR measurements are preferred since the replacement of alignment objects with samples often displace translation stages and make the ali...

  17. The diagnostic yield of fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography in recurrent testicular seminoma

    Directory of Open Access Journals (Sweden)

    Athanasios Bantis

    2016-01-01

    Full Text Available The use of positron emission tomography-computed tomography (PET-CT scan imaging is undoubtedly a significant evolution in oncological urology, although at present of limited use in every day urology practice. The aim of this study is to highlight the indication and diagnostic accuracy of fluorine-18 fluorodeoxyglucose PET/CT in the staging of a patient with metachronous bilateral testicular seminoma, elevated tumor markers, and equivocal conventional imaging findings.

  18. 18F-fluorodeoxyglucose positron emission tomography/computed tomography comparison of gastric lymphoma and gastric carcinoma

    OpenAIRE

    Li, Xiao-Feng; Fu, Qiang; Dong, You-Wen; Liu, Jian-Jing; Song,Xiu-yu; Dai, Dong; Zuo, Cong; Xu, Wen-Gui

    2016-01-01

    AIM To compare 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) features in gastric lymphoma and gastric carcinoma. METHODS Patients with newly diagnosed gastric lymphoma or gastric carcinoma who underwent 18F-FDG PET/CT prior to treatment were included in this study. We reviewed and analyzed the PET/CT features of gastric wall lesions, including FDG avidity, pattern (focal/diffuse), and intensity [maximal standard uptake value: (SUVmax)]. The correlati...

  19. Contrast-enhanced fluorodeoxyglucose positron emission tomography/contrast-enhanced computed tomography in mediastinal T-cell lymphoma with superior vena cava syndrome.

    Science.gov (United States)

    Santhosh, Sampath; Gorla, Arun Kumar Reddy; Bhattacharya, Anish; Varma, Subhash Chander; Mittal, Bhagwant Rai

    2016-01-01

    Positron emission tomography-computed tomography (PET/CT) is a routine investigation for the staging of lymphomas. Contrast-enhanced computed tomography is mandatory whenever parenchymal lesions, especially in the liver and spleen are suspected. We report a rare case of primary mediastinal T-cell lymphoma evaluated with contrast-enhanced PET/CT that showed features of superior vena cava syndrome.

  20. Role of computed tomography and radionuclide scintigraphy in the localization of osteomyelitis in flat bones

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, R.J.; Conway, J.J.; Poznanski, A.K.; Tachdjian, M.O.; Dias, L.S.; Kelikian, A.S.

    1985-03-01

    The combined use of radionuclide scintigraphy and computed tomography is recommended for evaluating children with laboratory and clinical data suggestive of flat bone osteomyelitis despite normal conventional radiographs. In addition, computed tomography may be helpful in the presence of abnormal radiographs in determining the exact location of the focus of osteomyelitis and the most suitable route for appropriate drainage or to obtain culture material.

  1. Just Scan It!-Weapon Reconstruction in Computed Tomography on Historical and Current Swiss Military Guns.

    Science.gov (United States)

    Franckenberg, Sabine; Binder, Thomas; Bolliger, Stephan; Thali, Michael J; Ross, Steffen G

    2016-09-01

    Cross-sectional imaging, such as computed tomography, has been increasingly implemented in both historic and recent postmortem forensic investigations. It aids in determining cause and manner of death as well as in correlating injuries to possible weapons. This study illuminates the feasibility of reconstructing guns in computed tomography and gives a distinct overview of historic and recent Swiss Army guns.

  2. Quantitative computed tomography measures of emphysema and airway wall thickness are related to respiratory symptoms

    DEFF Research Database (Denmark)

    Grydeland, Thomas B; Dirksen, Asger; Coxson, Harvey O

    2010-01-01

    There is limited knowledge about the relationship between respiratory symptoms and quantitative high-resolution computed tomography measures of emphysema and airway wall thickness.......There is limited knowledge about the relationship between respiratory symptoms and quantitative high-resolution computed tomography measures of emphysema and airway wall thickness....

  3. Visualization of simulated small vessels on computed tomography using a model-based iterative reconstruction technique

    Directory of Open Access Journals (Sweden)

    Toru Higaki

    2017-08-01

    Full Text Available This article describes a quantitative evaluation of visualizing small vessels using several image reconstruction methods in computed tomography. Simulated vessels with diameters of 1–6 mm made by 3D printer was scanned using 320-row detector computed tomography (CT. Hybrid iterative reconstruction (hybrid IR and model-based iterative reconstruction (MBIR were performed for the image reconstruction.

  4. Quantitative computed tomography measures of emphysema and airway wall thickness are related to respiratory symptoms

    DEFF Research Database (Denmark)

    Grydeland, Thomas B; Dirksen, Asger; Coxson, Harvey O

    2010-01-01

    There is limited knowledge about the relationship between respiratory symptoms and quantitative high-resolution computed tomography measures of emphysema and airway wall thickness.......There is limited knowledge about the relationship between respiratory symptoms and quantitative high-resolution computed tomography measures of emphysema and airway wall thickness....

  5. Multi-dimensional visualization of coronary aberrancies using multi detector computed tomography

    NARCIS (Netherlands)

    van Ooijen, P; Dorgelo, J; Tukker, W; Willemsen, H; Oudkerk, M; Lewis, BS; Halon, DA; Flugelman, MY; Gensini, GF

    2003-01-01

    The purpose of this study was to evaluate the usefulness of three and four dimensional visualization of multi detector computed tomography datasets for the evaluation of coronary aberrancies. Multi detector computed tomography (MDCT) datasets were obtained in thirteen patients following a standard p

  6. Dynamic 3D computed tomography scanner for vascular imaging

    Science.gov (United States)

    Lee, Mark K.; Holdsworth, David W.; Fenster, Aaron

    2000-04-01

    A 3D dynamic computed-tomography (CT) scanner was developed for imaging objects undergoing periodic motion. The scanner system has high spatial and sufficient temporal resolution to produce quantitative tomographic/volume images of objects such as excised arterial samples perfused under physiological pressure conditions and enables the measurements of the local dynamic elastic modulus (Edyn) of the arteries in the axial and longitudinal directions. The system was comprised of a high resolution modified x-ray image intensifier (XRII) based computed tomographic system and a computer-controlled cardiac flow simulator. A standard NTSC CCD camera with a macro lens was coupled to the electro-optically zoomed XRII to acquire dynamic volumetric images. Through prospective cardiac gating and computer synchronized control, a time-resolved sequence of 20 mm thick high resolution volume images of porcine aortic specimens during one simulated cardiac cycle were obtained. Performance evaluation of the scanners illustrated that tomographic images can be obtained with resolution as high as 3.2 mm-1 with only a 9% decrease in the resolution for objects moving at velocities of 1 cm/s in 2D mode and static spatial resolution of 3.55 mm-1 with only a 14% decrease in the resolution in 3D mode for objects moving at a velocity of 10 cm/s. Application of the system for imaging of intact excised arterial specimens under simulated physiological flow/pressure conditions enabled measurements of the Edyn of the arteries with a precision of +/- kPa for the 3D scanner. Evaluation of the Edyn in the axial and longitudinal direction produced values of 428 +/- 35 kPa and 728 +/- 71 kPa, demonstrating the isotropic and homogeneous viscoelastic nature of the vascular specimens. These values obtained from the Dynamic CT systems were not statistically different (p less than 0.05) from the values obtained by standard uniaxial tensile testing and volumetric measurements.

  7. Value of computer tomography and sonography in the investigation of the pancreas

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, K.; Frommhold, H.; Grauthoff, H.; Moedder, U.; Heuser, L. Braun, G.; Buurman, R.; Scherer, K. (Bonn Univ. (Germany, F.R.). Radiologische Klinik; Hamburg Univ. (Germany, F.R.). Radiologische Klinik und Strahleninstitut; Koeln Univ. (Germany, F.R.). Radiologisches Inst. und Poliklinik)

    1980-05-01

    Three hundred and five patients were examined by computer tomography and sonography. In 117 patients no abnormalities were found in the pancreas. The accuracy of computer tomography was 87%, of sonography 85%. In 41 patients the presence of a carcinoma of the pancreas was confirmed histologically. In this group the sensitivity of computer tomography was 83%, of sonography 85%. Thirty-four patients suffered from acute pancreatitis. In this group sensitivity of the two methods was equal at 79%. 113 patients had changes of chronic pancreatitis. Sensitivity of computer tomography was 84%, of sonography 70%. Computer tomography is better at demonstrating calcification in the pancreas. Atrophy of the pancreas cannot be diagnosed by sonography.

  8. Comparison of Adsorbed Skin Dose Received by Patients in Cone Beam Computed Tomography, Spiral and Conventional Computed Tomography Scanninng

    Directory of Open Access Journals (Sweden)

    Rahimi A

    2011-12-01

    Full Text Available Background and Aims: The evaluation of absorbed dose received by patients could give useful information for radiation risk estimation. This study was performed to compare the entrance skin dose received by patients in cone beam computed tomography (CBCT, conventional and spiral computed tomography (CT.Materials and Methods: In this experimental study, 81 calibrated TLD chips were used. the TLD chips were placed on facial, thyroid and end of sternum skin surface in patients referred for CT of the paranasal sinuses(3 TLD chips for each area to estimate the absorbed dose received by central part of radiation field, thyroid and out of field areas, respectively. The data were analyzed using one-way ANOVA and Tukey tests. Results: The dose delivered to the center of irradiated field was about 0.79±0.09 mGy in CBCT technique compared with 16.31±3.71 and 18.84±4.12 mGy for spiral and conventional CT, respectively. The received dose by the out of field areas was about 54 percent of central area dose. There was statistical significant relationship between the imaging modalities and absorbed dose received by patients (P=0.016. The least absorbed dose was for CBCT and the greatest dose was for conventional CT imaging technique.Conclusion: The dose delivered to central area of irradiated field in conventional and spiral CT imaging modalities was about 24 times greater than of that in CBCT. Also, the highest received dose was for central area of radiated field and the lowest dose was for the out of field areas.

  9. Iterative image reconstruction and its role in cardiothoracic computed tomography.

    Science.gov (United States)

    Singh, Sarabjeet; Khawaja, Ranish Deedar Ali; Pourjabbar, Sarvenaz; Padole, Atul; Lira, Diego; Kalra, Mannudeep K

    2013-11-01

    Revolutionary developments in multidetector-row computed tomography (CT) scanner technology offer several advantages for imaging of cardiothoracic disorders. As a result, expanding applications of CT now account for >85 million CT examinations annually in the United States alone. Given the large number of CT examinations performed, concerns over increase in population-based risk for radiation-induced carcinogenesis have made CT radiation dose a top safety concern in health care. In response to this concern, several technologies have been developed to reduce the dose with more efficient use of scan parameters and the use of "newer" image reconstruction techniques. Although iterative image reconstruction algorithms were first introduced in the 1970s, filtered back projection was chosen as the conventional image reconstruction technique because of its simplicity and faster reconstruction times. With subsequent advances in computational speed and power, iterative reconstruction techniques have reemerged and have shown the potential of radiation dose optimization without adversely influencing diagnostic image quality. In this article, we review the basic principles of different iterative reconstruction algorithms and their implementation for various clinical applications in cardiothoracic CT examinations for reducing radiation dose.

  10. Compensation for air voids in photoacoustic computed tomography image reconstruction

    Science.gov (United States)

    Matthews, Thomas P.; Li, Lei; Wang, Lihong V.; Anastasio, Mark A.

    2016-03-01

    Most image reconstruction methods in photoacoustic computed tomography (PACT) assume that the acoustic properties of the object and the surrounding medium are homogeneous. This can lead to strong artifacts in the reconstructed images when there are significant variations in sound speed or density. Air voids represent a particular challenge due to the severity of the differences between the acoustic properties of air and water. In whole-body small animal imaging, the presence of air voids in the lungs, stomach, and gastrointestinal system can limit image quality over large regions of the object. Iterative reconstruction methods based on the photoacoustic wave equation can account for these acoustic variations, leading to improved resolution, improved contrast, and a reduction in the number of imaging artifacts. However, the strong acoustic heterogeneities can lead to instability or errors in the numerical wave solver. Here, the impact of air voids on PACT image reconstruction is investigated, and procedures for their compensation are proposed. The contributions of sound speed and density variations to the numerical stability of the wave solver are considered, and a novel approach for mitigating the impact of air voids while reducing the computational burden of image reconstruction is identified. These results are verified by application to an experimental phantom.

  11. 3D ultrasound computer tomography: update from a clinical study

    Science.gov (United States)

    Hopp, T.; Zapf, M.; Kretzek, E.; Henrich, J.; Tukalo, A.; Gemmeke, H.; Kaiser, C.; Knaudt, J.; Ruiter, N. V.

    2016-04-01

    Ultrasound Computer Tomography (USCT) is a promising new imaging method for breast cancer diagnosis. We developed a 3D USCT system and tested it in a pilot study with encouraging results: 3D USCT was able to depict two carcinomas, which were present in contrast enhanced MRI volumes serving as ground truth. To overcome severe differences in the breast shape, an image registration was applied. We analyzed the correlation between average sound speed in the breast and the breast density estimated from segmented MRIs and found a positive correlation with R=0.70. Based on the results of the pilot study we now carry out a successive clinical study with 200 patients. For this we integrated our reconstruction methods and image post-processing into a comprehensive workflow. It includes a dedicated DICOM viewer for interactive assessment of fused USCT images. A new preview mode now allows intuitive and faster patient positioning. We updated the USCT system to decrease the data acquisition time by approximately factor two and to increase the penetration depth of the breast into the USCT aperture by 1 cm. Furthermore the compute-intensive reflectivity reconstruction was considerably accelerated, now allowing a sub-millimeter volume reconstruction in approximately 16 minutes. The updates made it possible to successfully image first patients in our ongoing clinical study.

  12. Motion management in positron emission tomography/computed tomography for radiation treatment planning.

    Science.gov (United States)

    Bettinardi, Valentino; Picchio, Maria; Di Muzio, Nadia; Gilardi, Maria Carla

    2012-09-01

    Hybrid positron emission tomography (PET)/computed tomography (CT) scanners combine, in a unique gantry, 2 of the most important diagnostic imaging systems, a CT and a PET tomograph, enabling anatomical (CT) and functional (PET) studies to be performed in a single study session. Furthermore, as the 2 scanners use the same spatial coordinate system, the reconstructed CT and PET images are spatially co-registered, allowing an accurate localization of the functional signal over the corresponding anatomical structure. This peculiarity of the hybrid PET/CT system results in improved tumor characterization for oncological applications, and more recently, it was found to be also useful for target volume definition (TVD) and treatment planning in radiotherapy (RT) applications. In fact, the use of combined PET/CT information has been shown to improve the RT treatment plan when compared with that obtained by a CT alone. A limiting factor to the accuracy of TVD by PET/CT is organ and tumor motion, which is mainly due to patient respiration. In fact, respiratory motion has a degrading effect on PET/CT image quality, and this is also critical for TVD, as it can lead to possible tumor missing or undertreatment. Thus, the management of respiratory motion is becoming an increasingly essential component in RT treatment planning; indeed, it has been recognized that the use of personalized motion information can improve TVD and, consequently, permit increased tumor dosage while sparing surrounding healthy tissues and organs at risk. This review describes the methods used for motion management in PET/CT for radiation treatment planning. The article covers the following: (1) problems caused by organ and lesion motion owing to respiration, and the artifacts generated on CT, PET, and PET/CT images; (2) data acquisition and processing techniques used to manage respiratory motion in PET/CT studies; and (3) the use of personalized motion information for TVD and radiation treatment planning.

  13. Relationship of computed tomography perfusion and positron emission tomography to tumour progression in malignant glioma

    Energy Technology Data Exchange (ETDEWEB)

    Yeung, Timothy P C [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Yartsev, Slav [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Lee, Ting-Yim [Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Imaging, The University of Western Ontario, London Health Sciences Centre, Victoria Hospital, Ontario, Canada, N6A 5W9 (Australia); Lawson Health Research Institute, St. Joseph' s Health Care London, Ontario, Canada, N6A 4V2 (Canada); Wong, Eugene [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Physics and Astronomy, The University of Western Ontario, Ontario, Canada, N6A 3K7 (Canada); He, Wenqing [Department of Statistical and Actuarial Sciences, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Fisher, Barbara; VanderSpek, Lauren L [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Macdonald, David [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Clinical Neurological Sciences, The University of Western Ontario, London Health Sciences Centre, University Hospital, Ontario, Canada, N6A 5A5 (Canada); Bauman, Glenn, E-mail: glenn.bauman@lhsc.on.ca [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada)

    2014-02-15

    Introduction: This study aimed to explore the potential for computed tomography (CT) perfusion and 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting sites of future progressive tumour on a voxel-by-voxel basis after radiotherapy and chemotherapy. Methods: Ten patients underwent pre-radiotherapy magnetic resonance (MR), FDG-PET and CT perfusion near the end of radiotherapy and repeated post-radiotherapy follow-up MR scans. The relationships between these images and tumour progression were assessed using logistic regression. Cross-validation with receiver operating characteristic (ROC) analysis was used to assess the value of these images in predicting sites of tumour progression. Results: Pre-radiotherapy MR-defined gross tumour; near-end-of-radiotherapy CT-defined enhancing lesion; CT perfusion blood flow (BF), blood volume (BV) and permeability-surface area (PS) product; FDG-PET standard uptake value (SUV); and SUV:BF showed significant associations with tumour progression on follow-up MR imaging (P < 0.0001). The mean sensitivity (±standard deviation), specificity and area under the ROC curve (AUC) of PS were 0.64 ± 0.15, 0.74 ± 0.07 and 0.72 ± 0.12 respectively. This mean AUC was higher than that of the pre-radiotherapy MR-defined gross tumour and near-end-of-radiotherapy CT-defined enhancing lesion (both AUCs = 0.6 ± 0.1, P ≤ 0.03). The multivariate model using BF, BV, PS and SUV had a mean AUC of 0.8 ± 0.1, but this was not significantly higher than the PS only model. Conclusion: PS is the single best predictor of tumour progression when compared to other parameters, but voxel-based prediction based on logistic regression had modest sensitivity and specificity.

  14. Prognostic value of 18-fluorodeoxyglucose positron emission tomography-computed tomography in resectable colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Jang Eun Lee; Sang Woo Kim; Jin Su Kim; Kyu Yong Choi; Won Kyung Kang; Seong Taek Oh; Ie Ryung Yoo

    2012-01-01

    AIM:To assess the prognostic value of preoperative 18 fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) in patients with resectable colorectal cancer.METHODS:One hundred sixty-three patients with resectable colorectal cancer who underwent FDG-PET/CT before surgery were included.Patient data including pathologic stage at presentation,histology,treatment,disease-free survival and the maximum standardized uptake value (SUVmax) of the primary tumor on FDGPET/CT were retrospectively analyzed.Median follow up duration was 756 (range,419-1355).The primary end point was disease-free survival.RESULTS:Twenty-five of 163 patients (15.3%) had recurrences.The median SUVmax values of the recurrence and no-recurrence groups were 8.9 (range,5-24) and 8.2 (range,0-23,P =0.998).Receiver operating characteristic (ROC) curve analysis showed no significant association between SUVmax and recurrence (area under the curve =0.5,P =0.998,95%CI:0.389-0.611).Because a statistically significant value was not found,SUVmax was dichotomized at its median of 8.6.The disease-free survival curve was analyzed using the median SUVmax (8.6) as the cut off.Univariate and multivariate analysis did not provide evidence that disease-free survival rates for the subgroups defined by the median SUVmax were significantly different (P =0.52,P =0.25).CONCLUSION:Our study suggests that the high FDG uptake of primary mass in resectable colorectal cancer doesn't have a significant relationship with tumor recurrence and disease-free survival.

  15. Gallium-67 Scintigraphy in the Era of Positron Emission Tomography and Computed Tomography; Tertiary centre experience

    Directory of Open Access Journals (Sweden)

    Badriya Al-Suqri

    2015-08-01

    Full Text Available Objectives: Although 18F-fluorodeoxyglucose positron emission tomography (PET/computed tomography (CT has largely replaced the use of gallium-67 (67Ga scintigraphy in the evaluation and follow-up of lymphoma patients, 67Ga scans are still of value, particularly in countries where no PET/CT service is available. The current study presents the experience of a tertiary care centre using 67Ga scintigraphy for the evaluation of lymphomas and infections. Methods: A retrospective review was conducted of all 67Ga scans performed between 2007 and 2011 at the Royal Hospital in Muscat, Oman. Images and reports of 67Ga scans were compared to clinical and radiological follow-up data including CT and PET/CT scans and biopsies when available. Results: A total of 74 patients were referred for 67Ga scintigraphy during this period with 12 patients excluded due to lack of follow-up data, resulting in 62 patients. Among these patients, 90 67Ga scans were performed, including 59 for lymphoma, 29 for infection and two for sarcoidosis assessment. Of the infection assessment scans, 22 were performed to assess pyrexia of unknown origin and seven for follow-up after known infections. Sensitivity and specificity were found to be 80% and 88%, respectively, for the lymphoma assessment scans. For the infection assessment scans, sensitivity and specificity were reported to be 80% and 100%, respectively. Conclusion: Results from this study were consistent with other reported rates of 67Ga scan sensitivity and specificity in the evaluation of lymphomas and infections. This indicates that 67Ga scintigraphy is a useful tool for these types of evaluations when PET/CT services are not available.

  16. Diagnostic value for extrahepatic metastases of hepatocellular carcinoma in positron emission tomography/computed tomography scan

    Institute of Scientific and Technical Information of China (English)

    Ji Eun Lee; Jae Young Jang; Soung Won Jeong; Sae Hwan Lee; Sang Gyune Kim; Sang-Woo Cha; Young Seok Kim

    2012-01-01

    AIM:To evaluated the value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scan in diagnosis of hepatocellular carcinoma (HCC) and extrahepatic metastases.METHODS:A total of 138 patients with HCC who had both conventional imaging modalities and 18F-FDG PET/CT scan done between November 2006 and March 2011 were enrolled.Diagnostic value of each imaging modality for detection of extrahepatic metastases was evaluated.Clinical factors and tumor characteristics including PET imaging were analyzed as indicative factors for metastases by univariate and multivariate methods.RESULTS:The accuracy of chest CT was significantly superior compared with the accuracy of PET imaging for detecting lung metastases.The detection rate of metastatic pulmonary nodule ≥ 1 cm was 12/13(92.3%),when < 1 cm was 2/10 (20%) in PET imaging.The accuracy of PET imaging was significantly superior compared with the accuracy of bone scan for detecting bone metastases.In multivariate analysis,increased tumor size (≥ 5 cm) (P =0.042) and increased average standardized uptake value (SUV)uptake (P =0.028) were predictive factors for extrahepatic metastases.Isometabolic HCC in PET imaging was inversely correlated in multivariate analysis (P =0.035).According to the receiver operating characteristic curve,the optimal cutoff of average SUV to predict extrahepatic metastases was 3.4.CONCLUSION:18F-FDG PET/CT scan is invaluable for detection of lung metastases larger than 1 cm and bone metastases.Primary HCC having larger than 5 cm and increased average SUV uptake more than 3.4should be considered for extrahepatic metastases.

  17. Single-photon emission computed tomography and positron-emission tomography assays for tissue oxygenation.

    Science.gov (United States)

    Chapman, J D; Schneider, R F; Urbain, J L; Hanks, G E

    2001-01-01

    Radiotherapy prescription can now be customized to target the major mechanism(s) of resistance of individual tumors. In that regard, functional imaging techniques should be exploited to identify the dominant mechanism(s). Tumor biology research has identified several mechanisms of tumor resistance that may be unique to radiation treatments. These fall into 3 broad areas associated with (1) tumor hypoxic fraction, (2) tumor growth rate, (3) and the intrinsic radiosensitivity of tumor clonogens. Imaging research has markers in various stages of development for quantifying relevant information about each of these mechanisms, and those that measure tumor oxygenation and predict for radioresistance are the most advanced. Positron-emission tomography (PET) measurement of oxygen 15 has yielded important information, particularly about brain tissue perfusion, metabolism, and function. Indirect markers of tumor hypoxia have exploited the covalent binding of bioreductive intermediates of azomycin-containing compounds whose uptakes are inversely proportional to intracellular oxygen concentrations. Pilot clinical studies with single-photon emission computed tomography (SPECT) and PET detection of radiolabeled markers to tumor hypoxia have been reported. Recently, other studies have attempted to exploit the reduction properties of both technetium and copper chelates for the selective deposition of radioactive metals in hypoxic tissues. A growing number of potentially useful isotopes are now available for labeling several novel chemicals that could have the appropriate specificity and sensitivity. Preclinical studies with "microSPECT" and "microPET" will be important to define the optimal radiodiagnostic(s) for measuring tissue oxygenation and for determining the time after their administration for optimal hypoxic signal acquisition. Radiolabeled markers of growth kinetics and intrinsic radiosensitivity of cells in solid tumors are also being developed. We conclude that

  18. Does positron emission tomography/computed tomography change management in colorectal cancer?

    Science.gov (United States)

    Falconer, Rachel; Connor, Saxon; Balasingam, Adrian; Eglinton, Tim

    2016-10-27

    Positron emission tomography/computed tomography (PET/CT) is used pre-operatively in patients with metastatic or recurrent colorectal cancer to identify those who have potentially curative disease. However, a recent randomized trial questioned the added benefit of PET/CT over conventional imaging in patients with liver metastases. The aim of this study was to determine the proportion of patients with colorectal cancer in whom PET/CT altered surgical management, in a single tertiary centre. This was a retrospective study of all patients with colorectal cancer who had a PET/CT for colorectal cancer, funded by the Canterbury District Health Board between 2010 and 2014. Some 111 PET/CT scans were performed on 105 patients. A total of 38% of PET/CT were for patients with known or suspected liver metastases, 23% for suspected local recurrence and 18% for known or suspected lung metastases. Five scans were for post-operative patients with a rising carcinoembryonic antigen and no attributable source on conventional imaging. PET/CT identified additional extrahepatic sites of disease in 19 of 111 (17%) scans in patients deemed to have potentially operable disease. Overall, PET/CT altered surgical management following six of 42 (14%) scans for patients with liver metastases, four of 20 (20%) scans for patients with lung metastases and six of 26 (23%) scans for patients with local recurrence. PET/CT remains a useful adjunct to conventional imaging in the pre-operative workup of patients with colorectal cancer. © 2016 Royal Australasian College of Surgeons.

  19. Pitfalls in Positron Emission Tomography/Computed Tomography Imaging: Causes and Their Classifications

    Institute of Scientific and Technical Information of China (English)

    Tian-ran Li; Jia-he Tian; Hui Wang; Zi-qian Chen; Chun-lei Zhao

    2009-01-01

    Objective To describe the pitfalls in positron emission tomography/computed tomography (PET/CT) imaging and classify them according to the principles of their generation. Methods We summarized retrospectively the 18F-fluorodeoxyglucose (FDP) PET/CT imaging pitfalls through reviewing the PET/CT images of 872 patients. The pitfalls were divided into artifacts and infrequent physiological uptake, and the artifacts were further classified according to their causes. Meanwhile, we calculated the incidences of various pitfalls. Whether the PET/CT pitfalls influenced the diagnostic decision was analyzed. The appearances of pitfalls in PET were also described. Results Pitfalls could be found in PET/CT images of 684 (78.4%) patients. Artifacts were found in 664 (76.15%) patients, and could be classified into self-factor artifacts and equipment- or technology- related artifacts. Among self-factor artifacts, respiratory motion (57.5%), postprandial or hyperglycemia artifacts (2.41%), and metal or high density matter artifacts (1.38%) were frequent. As for equipment- or technology-related factors, injection point outleakage or radiotracer contamination (13.88%) and truncation artifacts (1.83%) were most common ones. Infrequent physiological FDG uptakes, including fatty uptake, endometrial uptake, and bilateral breast feeding period uptake, were found in 20 (2.29%) patients. Among all pitfalls, the artifacts in 92 (13.4%) patients and infrequent physiological uptakes in 6 (0.88%) patients affected the diagnostic results. Artifact images in PET could be described as hot or cold area and the images of infrequent physiological uptake were always shown as hot area. Conclusions The incidence of pitfall in PET/CT imaging was high and the causes of pitfalls are various. Among all causes that artifacts generated, respiratory motion is the most common. Some pitfalls may disturb clinical physicians' decision, so it is important to recognize artifacts and physiological uptake, and

  20. Diagnostic value of high resolutional computed tomography of spine

    Energy Technology Data Exchange (ETDEWEB)

    Yang, S. M.; Im, S. K.; Sohn, M. H.; Lim, K. Y.; Kim, J. K.; Choi, K. C. [Jeonbug National University College of Medicine, Seoul (Korea, Republic of)

    1984-03-15

    Non-enhanced high resolution computed tomography provide clear visualization of soft tissue in the canal and bony details of spine, particularly of the lumbar spine. We observed 70 cases of spine CT using GE CT/T 8800 scanner during the period from Dec. 1982 to Sep. 1983 at Jeonbug National University Hospital. The results were as follows: 1. The sex distribution of cases were 55 males and 15 females : age was from 17 years to 67 years; sites were 11 cervical spine, 5 thoracic spine and 54 lumbosacral spine. 2. CT diagnosis showed 44 cases of lumbar disc herniation, 7 cases of degenerative disease, 3 cases of spine fracture and each 1 cases of cord tumor, metastatic tumor, spontaneous epidural hemorrhage, epidural abscess, spine tbc., meningocele with diastematomyelia. 3. Sites of herniated nucleus pulposus were 34 cases (59.6%) between L4-5 interspace and 20 cases (35.1%) between L5-S1 interspace. 13 cases (29.5%) of lumbar disc herniation disclosed multiple lesions. Location of herniation were central type in 28 cases(49.1%), right-central type in 12 cases(21.2%), left-central type in 11 cases (19.2%) and far lateral type in 6 cases(10.5%). 4. CT findings of herniated nucleus pulposus were as follows : focal protrusion of posterior disc margin and obliteration of anterior epidural fat in all cases, dural sac indentation in 26 cases(45.6%), soft tissue mass in epidural fat in 21 cases(36.8%), displacement or compression of nerve root sheath in 12 cases(21%). 5. Multiplanar reformatted images and Blink mode provide more effective evaluation about definite level and longitudinal dimension of lesion, such as obscure disc herniation, spine fracture, cord tumor and epidural abscess. 6. Non-enhanced and enhanced high resolutional computed tomography were effectively useful in demonstrating compression or displacement of spinal cord and nerve root, examing congenital anomaly such as meningocele and primary or metastatic spinal lesions.

  1. Computer-aided classification of lung nodules on computed tomography images via deep learning technique.

    Science.gov (United States)

    Hua, Kai-Lung; Hsu, Che-Hao; Hidayati, Shintami Chusnul; Cheng, Wen-Huang; Chen, Yu-Jen

    2015-01-01

    Lung cancer has a poor prognosis when not diagnosed early and unresectable lesions are present. The management of small lung nodules noted on computed tomography scan is controversial due to uncertain tumor characteristics. A conventional computer-aided diagnosis (CAD) scheme requires several image processing and pattern recognition steps to accomplish a quantitative tumor differentiation result. In such an ad hoc image analysis pipeline, every step depends heavily on the performance of the previous step. Accordingly, tuning of classification performance in a conventional CAD scheme is very complicated and arduous. Deep learning techniques, on the other hand, have the intrinsic advantage of an automatic exploitation feature and tuning of performance in a seamless fashion. In this study, we attempted to simplify the image analysis pipeline of conventional CAD with deep learning techniques. Specifically, we introduced models of a deep belief network and a convolutional neural network in the context of nodule classification in computed tomography images. Two baseline methods with feature computing steps were implemented for comparison. The experimental results suggest that deep learning methods could achieve better discriminative results and hold promise in the CAD application domain.

  2. The Comparison of Ultrasonography and Non Enhanced Helical Computed Tomography in the Diagnosis of Ureteral Calculi

    Directory of Open Access Journals (Sweden)

    İlhan Kılınç

    2007-01-01

    Full Text Available Intravenous urography, ultrasonography, and non-contrast spiral computed tomography have been used to diagnose ureteral calculi. We aimed to compare the accuracy of non-contrast spiral computed tomography with ultrasonography in the evaluation of patients with renal colic.Fourty-one patients with flank pain were examined with both computed tomography and ultrasonography over a period of 11 months. Findings of ultrasonography and computed tomography of 28 patients in whom üreteral stones were confirmed by standart methods were comparedUreteral calculi were diagnosed in 28 of 41 patients. Ureteral stones could be demonstrated in 18 patients by ultrasonography and in 27 patients by computed tomography. Ultrasonography showed 64.3% sensitivity and 100% specificity in the diagnosis of ureterolithiasis; computed tomography showed 96.4% and 100%, respectively. Spiral computed tomography is superior to ultrasonography in the demonstration of ureteral calculi in patients with renal colic. But because of higher cost and higher radiation dose, it should be reserved for symptomatic cases in whom ultrasonography is non-diagnostic.

  3. Fluorodeoxyglucose positron emission tomography/computed tomography findings in a patient with cerebellar mutism after operation in posterior fossa.

    Science.gov (United States)

    Gedik, Gonca Kara; Sari, Oktay; Köktekir, Ender; Akdemir, Gökhan

    2017-04-01

    Cerebellar mutism is a transient period of speechlessness that evolves after posterior fossa surgery in children. Although direct cerebellar and brain stem injury and supratentorial dysfunction have been implicated in the mediation of mutism, the pathophysiological mechanisms involved in the evolution of this kind of mutism remain unclear. Magnetic resonance imaging revealed dentatothalamocortical tract injuries and single photon emission computed tomography showed cerebellar and cerebral hypoperfusion in patients with cerebellar mutism. However, findings with (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in this group of patients have not been documented previously. In this clinical case, we report a patient who experienced cerebellar mutism after undergoing a posterior fossa surgery. Right cerebellar and left frontal lobe hypometabolism was shown using FDG PET/CT. The FDG metabolism of both the cerebellum and the frontal lobe returned to normal levels after the resolution of the mutism symptoms. Copyright © 2017. Published by Elsevier Taiwan.

  4. Fluorodeoxyglucose positron emission tomography/computed tomography findings in a patient with cerebellar mutism after operation in posterior fossa

    Directory of Open Access Journals (Sweden)

    Gonca Kara Gedik

    2017-03-01

    Full Text Available Cerebellar mutism is a transient period of speechlessness that evolves after posterior fossa surgery in children. Although direct cerebellar and brain stem injury and supratentorial dysfunction have been implicated in the mediation of mutism, the pathophysiological mechanisms involved in the evolution of this kind of mutism remain unclear. Magnetic resonance imaging revealed dentatothalamocortical tract injuries and single photon emission computed tomography showed cerebellar and cerebral hypoperfusion in patients with cerebellar mutism. However, findings with 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT in this group of patients have not been documented previously. In this clinical case, we report a patient who experienced cerebellar mutism after undergoing a posterior fossa surgery. Right cerebellar and left frontal lobe hypometabolism was shown using FDG PET/CT. The FDG metabolism of both the cerebellum and the frontal lobe returned to normal levels after the resolution of the mutism symptoms.

  5. Data on analysis of coronary atherosclerosis on computed tomography and 18F-sodium fluoride positron emission tomography

    Directory of Open Access Journals (Sweden)

    Toshiro Kitagawa

    2017-08-01

    Full Text Available This article contains the data showing illustrative examples of plaque classification on coronary computed tomography angiography (CCTA and measurement of 18F-sodium fluoride (18F-NaF uptake in coronary atherosclerotic lesions on positron emission tomography (PET. We divided the lesions into one of three plaque types on CCTA (calcified plaque, non-calcified plaque, partially calcified plaque. Focal 18F-NaF uptake of each lesion was quantified using maximum tissue-to-background ratio. This article also provides a representative case with a non-calcified coronary plaque detected on CCTA and identified on 18F-NaF PET/non-contrast computed tomography based on a location of a vessel branch as a landmark. These complement the data reported by Kitagawa et al. (2017 [1].

  6. Numerical observer for atherosclerotic plaque classification in spectral computed tomography.

    Science.gov (United States)

    Lorsakul, Auranuch; Fakhri, Georges El; Worstell, William; Ouyang, Jinsong; Rakvongthai, Yothin; Laine, Andrew F; Li, Quanzheng

    2016-07-01

    Spectral computed tomography (SCT) generates better image quality than conventional computed tomography (CT). It has overcome several limitations for imaging atherosclerotic plaque. However, the literature evaluating the performance of SCT based on objective image assessment is very limited for the task of discriminating plaques. We developed a numerical-observer method and used it to assess performance on discrimination vulnerable-plaque features and compared the performance among multienergy CT (MECT), dual-energy CT (DECT), and conventional CT methods. Our numerical observer was designed to incorporate all spectral information and comprised two-processing stages. First, each energy-window domain was preprocessed by a set of localized channelized Hotelling observers (CHO). In this step, the spectral image in each energy bin was decorrelated using localized prewhitening and matched filtering with a set of Laguerre-Gaussian channel functions. Second, the series of the intermediate scores computed from all the CHOs were integrated by a Hotelling observer with an additional prewhitening and matched filter. The overall signal-to-noise ratio (SNR) and the area under the receiver operating characteristic curve (AUC) were obtained, yielding an overall discrimination performance metric. The performance of our new observer was evaluated for the particular binary classification task of differentiating between alternative plaque characterizations in carotid arteries. A clinically realistic model of signal variability was also included in our simulation of the discrimination tasks. The inclusion of signal variation is a key to applying the proposed observer method to spectral CT data. Hence, the task-based approaches based on the signal-known-exactly/background-known-exactly (SKE/BKE) framework and the clinical-relevant signal-known-statistically/background-known-exactly (SKS/BKE) framework were applied for analytical computation of figures of merit (FOM). Simulated data of a

  7. A constrained conjugate gradient algorithm for computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, S.G.; Goodman, D.M. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    Image reconstruction from projections of x-ray, gamma-ray, protons and other penetrating radiation is a well-known problem in a variety of fields, and is commonly referred to as computed tomography (CT). Various analytical and series expansion methods of reconstruction and been used in the past to provide three-dimensional (3D) views of some interior quantity. The difficulties of these approaches lie in the cases where (a) the number of views attainable is limited, (b) the Poisson (or other) uncertainties are significant, (c) quantifiable knowledge of the object is available, but not implementable, or (d) other limitations of the data exist. We have adapted a novel nonlinear optimization procedure developed at LLNL to address limited-data image reconstruction problems. The technique, known as nonlinear least squares with general constraints or constrained conjugate gradients (CCG), has been successfully applied to a number of signal and image processing problems, and is now of great interest to the image reconstruction community. Previous applications of this algorithm to deconvolution problems and x-ray diffraction images for crystallography have shown the great promise.

  8. Molecular imaging with dynamic contrast-enhanced computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Miles, K.A., E-mail: k.a.miles@bsms.ac.u [Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, University of Sussex, Falmer, Brighton (United Kingdom)

    2010-07-15

    Dynamic contrast-enhanced computed tomography (DCE-CT) is a quantitative technique that employs rapid sequences of CT images after bolus administration of intravenous contrast material to measure a range of physiological processes related to the microvasculature of tissues. By combining knowledge of the molecular processes underlying changes in vascular physiology with an understanding of the relationship between vascular physiology and CT contrast enhancement, DCE-CT can be redefined as a molecular imaging technique. Some DCE-CT derived parameters reflect tissue hypoxia and can, therefore, provide information about the cellular microenvironment. DCE-CT can also depict physiological processes, such as vasodilatation, that represent the physiological consequences of molecular responses to tissue hypoxia. To date the main applications have been in stroke and oncology. Unlike some other molecular imaging approaches, DCE-CT benefits from wide availability and ease of application along with the use of contrast materials and software packages that have achieved full regulatory approval. Hence, DCE-CT represents a molecular imaging technique that is applicable in clinical practice today.

  9. Quantitative computed tomography imaging of airway remodeling in severe asthma.

    Science.gov (United States)

    Grenier, Philippe A; Fetita, Catalin I; Brillet, Pierre-Yves

    2016-02-01

    Asthma is a heterogeneous condition and approximately 5-10% of asthmatic subjects have severe disease associated with structure changes of the airways (airway remodeling) that may develop over time or shortly after onset of disease. Quantitative computed tomography (QCT) imaging of the tracheobronchial tree and lung parenchyma has improved during the last 10 years, and has enabled investigators to study the large airway architecture in detail and assess indirectly the small airway structure. In severe asthmatics, morphologic changes in large airways, quantitatively assessed using 2D-3D airway registration and recent algorithms, are characterized by airway wall thickening, luminal narrowing and bronchial stenoses. Extent of expiratory gas trapping, quantitatively assessed using lung densitometry, may be used to assess indirectly small airway remodeling. Investigators have used these quantitative imaging techniques in order to attempt severity grading of asthma, and to identify clusters of asthmatic patients that differ in morphologic and functional characteristics. Although standardization of image analysis procedures needs to be improved, the identification of remodeling pattern in various phenotypes of severe asthma and the ability to relate airway structures to important clinical outcomes should help target treatment more effectively.

  10. Computed Tomography Findings in Deep Neck Infections in Children

    Directory of Open Access Journals (Sweden)

    Ayşe Seçil Ekşioğlu

    2014-03-01

    Full Text Available Aim: This study aims to review the computed tomography (CT findings in children with deep neck infections. The crucial role of CT in the diagnosis is emphasized. Methods: Contrast enhanced CT images and medical records of twelve children (4 girls, 8 boys, age range: 1-14 years, mean age: 9 diagnosed with deep neck infection were retrospectively evaluated. Positive CT findings of deep neck infection were: cellulitis, increased fatty tissue echogenicity, loss of soft tissue planes, myositis, and necrotic lymphadenopathy; presence of phlegmon, peritonsillar, retropharyngeal or parapharyngeal abscess. The first four findings were considered as ‘early findings’ while the presence of an abscess indicated advanced infection and was solely enough to make a diagnosis. Results: 42% of the children with deep neck infections had necrotic cervical lymphadenopathies. 5 children (52% had cellulitis, 11 (92% had increased fatty tissue dansity, and 6 (50% children had myositis. Deep neck abscesses (3 retropharyngeal, 4 parapharyngeal, 2 peritonsillar were depicted in 7 children and phlegmon in one child. 2 patients had combined parapharyngeal/retropharyngeal abscesses. The most frequent type was parapharyngeal abcess. Conclusion: CT imaging has a crucial role in the diagnosis and follow-up of deep neck infections in children and is the preferred modality of choice. (The Me­di­cal Bul­le­tin of Ha­se­ki 2014; 52: 34-8

  11. Quantitative Computed Tomography and image analysis for advanced muscle assessment

    Directory of Open Access Journals (Sweden)

    Kyle Joseph Edmunds

    2016-06-01

    Full Text Available Medical imaging is of particular interest in the field of translational myology, as extant literature describes the utilization of a wide variety of techniques to non-invasively recapitulate and quantity various internal and external tissue morphologies. In the clinical context, medical imaging remains a vital tool for diagnostics and investigative assessment. This review outlines the results from several investigations on the use of computed tomography (CT and image analysis techniques to assess muscle conditions and degenerative process due to aging or pathological conditions. Herein, we detail the acquisition of spiral CT images and the use of advanced image analysis tools to characterize muscles in 2D and 3D. Results from these studies recapitulate changes in tissue composition within muscles, as visualized by the association of tissue types to specified Hounsfield Unit (HU values for fat, loose connective tissue or atrophic muscle, and normal muscle, including fascia and tendon. We show how results from these analyses can be presented as both average HU values and compositions with respect to total muscle volumes, demonstrating the reliability of these tools to monitor, assess and characterize muscle degeneration.

  12. Multidetector Computed Tomography of Cervical Spine Fractures in Ankylosing Spondylitis

    Energy Technology Data Exchange (ETDEWEB)

    Koivikko, M.P.; Kiuru, M.J.; Koskinen, S.K. [Helsinki Univ. Central Hospital, Toeoeloe Trauma Center (Finland). Dept. of Radiology

    2004-11-01

    Purpose: To analyze multidetector computed tomography (MDCT) cervical spine findings in trauma patients with advanced ankylosing spondylitis (AS). Material and Methods: Using PACS, 2282 cervical spine MDCT examinations requested by emergency room physicians were found during a period of 3 years. Of these patients, 18 (16 M, aged 41-87, mean 57 years) had advanced AS. Primary imaging included radiography in 12 and MRI in 11 patients. Results: MDCT detected one facet joint subluxation and 31 fractures in 17 patients: 14 transverse fractures, 8 spinous process fractures, 2 Jefferson's fractures, 1 type I and 2 type II odontoid process fractures, and 1 each: atlanto-occipital joint fracture and C2 laminar fracture plus isolated transverse process and facet joint fractures. Radiographs detected 48% and MRI 60% of the fractures. MRI detected all transverse and odontoid fractures, demonstrating spinal cord abnormalities in 72%. Conclusion: MDCT is superior to plain radiographs or MRI, showing significantly more injuries and yielding more information on fracture morphology. MRI is valuable, however, in evaluating the spinal cord and soft-tissue injuries. Fractures in advanced AS often show an abnormal orientation and are frequently associated with spinal cord injuries. In these patients, for any suspected cervical spine injuries, MDCT is therefore the imaging modality of choice.

  13. Logarithmic amplifier for computed tomography tasks using fluoroscopic projections.

    Science.gov (United States)

    Buliev, I; Badea, C; Pallikarakis, N

    2002-01-01

    The image intensifier (II)-based imaging systems, as radiotherapy simulators or C-arm X-ray units, have also been used for image acquisition in computed tomography. When analogue-to-digital conversion is performed on the output signal of the television camera, the accuracy for low-amplitude video signals, corresponding to X-ray pathways crossing high attenuation structures, is limited. To deal with this lack of accuracy, we investigated the benefits of using a logarithmic amplifier (LOGAMP) inserted between the television camera output and the analogue-to-digital converter (ADC) in the image acquisition chain. Such a device was intended to provide better use of the available ADCs of a given resolution and actually to reduce the quantization noise. Simulated data were used in this study, and cases with and without logarithmic amplifier were compared. Based on the simulation results, we formulate requirements for several signal and acquisition system parameters where the use of such a circuit is recommended.

  14. Determination of dosimetric quantities in pediatric abdominal computed tomography scans

    Energy Technology Data Exchange (ETDEWEB)

    Jornada, Tiago da Silva [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina. Dept. de Diagnostipo por Imagem; Silva, Teogenes Augusto da, E-mail: silvata@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2014-09-15

    Objective: aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL). Materials and methods: the study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom. Results: No significant difference was observed in the values for weighted air kerma index (C{sub W}), but the differences were relevant in values for volumetric air kerma index (C{sub VOL}), air kerma-length product (P{sub KL,CT}) and effective dose. Conclusion: Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, P{sub KL,CT} and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans. (author)

  15. Value of Multidetector Computed Tomography in Assessing Blunt Multitrauma Patients

    Energy Technology Data Exchange (ETDEWEB)

    Ahvenjaervi, L.; Mattila, L.; Ojala, R.; Tervonen, O. [Oulu Univ. Hospital (Finland). Dept. of Diagnostic Radiology

    2005-04-01

    Purpose: To find out if multidetector computed tomography (MDCT), using a dedicated trauma protocol, provides sufficient diagnostic information of the injuries of blunt multitrauma patients to enable the planning of treatment for all body compartments. Material and Methods: One-hundred-and-thirty-three patients exposed to high-energy trauma were referred and scanned with the standardized MDCT multitrauma protocol. The imaging protocol consisted of axial scanning of the head and helical scanning of the facial bones, cervical spine, thorax, abdomen, and pelvis. The scanning times were 12 s for the head, 19-21 s for the facial bones and cervical spine (1 mm collimation), and 32-50 s for the thorax, abdomen, and pelvis (2 mm collimation). One-hundred-and-forty milliliters of non-iodinated contrast material (300 mg I/ml) was administered intravenously at 3 ml/s. Results: Ninety-nine of the patients (74%) had at least one finding consistent with trauma. The most frequent findings were in the thorax in 58 patients (44%). Nineteen false-negative findings and two false-positive findings were made. The overall sensitivity of MDCT was 94%, specificity 100%, and accuracy 97%. Conclusion: MDCT is accurate in the assessment of blunt multitrauma patients. The decision to treat the patient can be made on the basis of MDCT with a reasonable level of certainty.

  16. Proton computed tomography using a 1D silicon diode array.

    Science.gov (United States)

    Wang, Peng; Cammin, Jochen; Bisello, Francesca; Solberg, Timothy D; McDonough, James E; Zhu, Timothy C; Menichelli, David; Teo, Boon-Keng Kevin

    2016-10-01

    Proton radiography (PR) and proton computed tomography (PCT) can be used to measure proton stopping power directly. However, practical and cost effective proton imaging detectors are not widely available. In this study, the authors investigated the feasibility of proton imaging using a silicon diode array. A one-dimensional silicon diode detector array (1DSDA) was aligned with the central axis (CAX) of the proton beam. Polymethyl methacrylate (PMMA) slabs were used to find the correspondence between the water equivalent thickness (WET) and 1DSDA channel number. Two-dimensional proton radiographs were obtained by translation and rotation of a phantom relative to CAX while the proton nozzle and 1DSDA were kept stationary. A PCT image of one slice of the phantom was reconstructed using filtered backprojection. PR and PCT images of the PMMA cube were successfully acquired using the 1DSDA. The WET of the phantom was measured using PR data. The resolution and maximum error in WET measurement are 2.0 and 1.5 mm, respectively. Structures down to 2.0 mm in size could be resolved completely. Reconstruction of a PCT image showed very good agreement with simulation. Limitations in spatial resolution are attributed to limited spatial sampling, beam collimation, and proton scatter. The results demonstrate the feasibility of using silicon diode arrays for proton imaging. Such a device can potentially offer fast image acquisition and high spatial and energy resolution for PR and PCT.

  17. Computed tomography dose optimisation in cystic fibrosis:A review

    Institute of Scientific and Technical Information of China (English)

    Helena Ferris; Maria Twomey; Fiachra Moloney; Siobhan B O’Neill; Kevin Murphy; Owen J O’Connor; Michael Maher

    2016-01-01

    Cystic fibrosis(CF)is the most common autosomal recessive disease of the Caucasian population worldwide,with respiratory disease remaining the most relevant source of morbidity and mortality.Computed tomography(CT)is frequently used for monitoring disease complications and progression.Over the last fifteen years there has been a six-fold increase in the use of CT,which has lead to a growing concern in relation to cumulative radiation exposure.The challenge to the medical profession is to identify dose reduction strategies that meet acceptable image quality,but fulfil the requirements of a diagnostic quality CT.Dose-optimisation,particularly in CT,is essential as it reduces the chances of patients receiving cumulative radiation doses in excess of 100 m Sv,a dose deemed significant by the United Nations Scientific Committee on the Effects of Atomic Radiation.This review article explores the current trends in imaging in CF with particular emphasis on new developments in dose optimisation.

  18. Image quality of mixed convolution kernel in thoracic computed tomography.

    Science.gov (United States)

    Neubauer, Jakob; Spira, Eva Maria; Strube, Juliane; Langer, Mathias; Voss, Christian; Kotter, Elmar

    2016-11-01

    The mixed convolution kernel alters his properties geographically according to the depicted organ structure, especially for the lung. Therefore, we compared the image quality of the mixed convolution kernel to standard soft and hard kernel reconstructions for different organ structures in thoracic computed tomography (CT) images.Our Ethics Committee approved this prospective study. In total, 31 patients who underwent contrast-enhanced thoracic CT studies were included after informed consent. Axial reconstructions were performed with hard, soft, and mixed convolution kernel. Three independent and blinded observers rated the image quality according to the European Guidelines for Quality Criteria of Thoracic CT for 13 organ structures. The observers rated the depiction of the structures in all reconstructions on a 5-point Likert scale. Statistical analysis was performed with the Friedman Test and post hoc analysis with the Wilcoxon rank-sum test.Compared to the soft convolution kernel, the mixed convolution kernel was rated with a higher image quality for lung parenchyma, segmental bronchi, and the border between the pleura and the thoracic wall (P kernel, the mixed convolution kernel was rated with a higher image quality for aorta, anterior mediastinal structures, paratracheal soft tissue, hilar lymph nodes, esophagus, pleuromediastinal border, large and medium sized pulmonary vessels and abdomen (P kernel cannot fully substitute the standard CT reconstructions. Hard and soft convolution kernel reconstructions still seem to be mandatory for thoracic CT.

  19. Evaluation of myocardial bridging by coronary computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Marcio Vinicius Lins; Rabelo, Daniel Rocha; Siqueira, Maria Helena Albernaz, E-mail: marciovlbarros@uol.com.br [Hospital Mater Dei, Belo Horizonte, MG (Brazil); Garretto, Luiza Samarane; Paula, Marcela Mascarenhas De; Carvalho, Marina Oliveira; Alves, Marina Rangel Moreira Barros [Faculdade de Saude e Ecologia Humana (FASEH), Vespasiano, MG (Brazil)

    2013-01-15

    The myocardial bridge (MB) is defined as a segment of an epicardial coronary artery that has an intramural course in the myocardium. Although MB is clinically silent in most cases, has been associated with myocardial ischemia, arrhythmias and sudden death. Coronary conventional angiography is the gold standard for detection of MB, but is invasive and cannot be sufficiently sensitive compared to autopsy studies. Recently, multislice computed tomography of coronary arteries (MCTCA) has allowed the detection of coronary artery course, including PM. Objectives: to evaluate MB prevalence in patients with suspected coronary artery disease undergoing MCTCA and to evaluate the predictive value of this method at medium term. Methods: during the period 2008 to 2011, 498 consecutive patients were examined by TMC for the diagnosis of coronary artery disease, being conducted to evaluate the presence of BM and followed for a mean follow-up of 23 months for the occurrence of cardiovascular hard events (death, hospitalization or revascularization). Results: patients mean age was 55.3 ± 14.2, being male 71.1%. Among the patients, 7.6% (38 patients) showed MB. Main findings included angina pectoris in 40% and a positive stress test in 34%. 34.2% had atherosclerotic disease, and one patient had significant coronary stenosis. During follow-up, no patients showed adverse events. Conclusion: MCTCA is a noninvasive technique with high accuracy in anatomical evaluation of the coronary arteries and may be particularly useful to assess the incidence, location and morphology of myocardial bridging in vivo. (author)

  20. Computed tomography imaging system design for shape threat detection

    Science.gov (United States)

    Masoudi, Ahmad; Thamvichai, Ratchaneekorn; Neifeld, Mark A.

    2017-04-01

    In the first part of this work, we present two methods for improving the shape-threat detection performance of x-ray computed tomography. Our work uses a fixed-gantry system employing 25 x-ray sources. We first utilize Kullback-Leibler divergence and Mahalanobis distance to determine the optimal single-source single-exposure measurement. The second method employs gradient search on Bhattacharyya bound on error rate (Pe) to determine an optimal multiplexed measurement that simultaneously utilizes all available sources in a single exposure. With limited total resources of 106 photons, the multiplexed measurement provides a 41.8× reduction in Pe relative to the single-source measurement. In the second part, we consider multiple exposures and develop an adaptive measurement strategy for x-ray threat detection. Using the adaptive strategy, we design the next measurement based on information retrieved from previous measurements. We determine both optimal "next measurement" and stopping criterion to insure a target Pe using sequential hypothesis testing framework. With adaptive single-source measurements, we can reduce Pe by a factor of 40× relative to the measurements employing all sources in sequence. We also observe that there is a trade-off between measurement SNR and number of detectors when we study the performance of systems with reduced detector numbers.

  1. Perfusion computed tomography evaluation of angiogenesis in liver cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Han Feng [Xuanwu Hospital, Capital Medical University, Department of Clinical Pain, Beijing (China); Hospital of North Sichuan Medical College, Department of Radiology, Nanchong City, Sichuan Province (China); Du, Yong; Xu, Xiao Xue; Li, Yang [Hospital of North Sichuan Medical College, Department of Radiology, Nanchong City, Sichuan Province (China); Ni, Jia Xiang [Xuanwu Hospital, Capital Medical University, Department of Clinical Pain, Beijing (China); Zhou, Xiang Ping [West China Hospital, Sichuan University, Department of Radiology, Chengdu City, Sichuan Province (China); Li, Jin Dong [Hospital of North Sichuan Medical College, Department of General Surgery, Nanchong City, Sichuan Province (China); Zhang, Qing [Hospital of North Sichuan Medical College, Department of Ultrasound, Nanchong City, Sichuan Province (China)

    2010-06-15

    To investigate the value of computed tomography (CT) perfusion imaging for assessment of angiogenesis in liver cancer. Twenty-one patients with histologically proven liver cancer underwent CT perfusion examination. We compared the following perfusion parameters in the tumour area versus the non-tumour area: total blood flow (TBF), hepatic arterial perfusion (HAP), hepatic portal perfusion (HPP) and hepatic arterial perfusion index (HAPI). Slices of postoperative specimen were stained with haematoxylin-eosin and anti-CD34 immunohistochemistry. The slices were evaluated with emphasis on the CD34-positive neovasculature in the tumour parenchyma. Tumour microvascular density (MVD) was calculated according to the Weidner method. Pearson correlation was used to detect correlations between tumour MVD and tumour perfusion parameters. TBF and HPP in the tumour area were lower than in the non-tumour area (P < 0.05). HAP and HAPI in the tumour area were higher than those of the non-tumour area (P < 0.05). TBF and HAP in the tumour area correlated with MVD in the tumour (P < 0.05), with correlation coefficients of 0.849 and 0.829, respectively. CT perfusion imaging can quantitatively assess the blood supply and its distribution in liver cancer. TBF or HAP may be a useful parameter in assessing angiogenesis of liver cancer. (orig.)

  2. Efficacy of cholangiography under helical computed tomography for laparoscopic cholecystectomy

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Motoya; Hishiyama, Houhei [Asahikawa Red Cross Hospital, Hokkaido (Japan); Kondo, Satoshi; Katoh, Hiroyuki [Hokkaido Univ., Sapporo (Japan). Graduate School of Medicine

    2002-05-01

    Although laparoscopic cholecystectomy (LC) is known to be safe, the optimal imaging technique for examining the common bile duct and cystic duct prior to laparoscopic intervention remains controversial. The objective of this study was to evaluate the efficacy of cholangiography under helical computed tomography (helical CT cholangiography) for LC. We studied 53 consecutive patients who underwent LC carried out by the same surgeon. The data of 23 of these patients who had undergone LC before the introduction of helical CT were used as the reference standard. Among the 53 patients, 28 were prospectively randomized for preoperative biliary tract evaluation with versus without helical CT cholangiography, into a CT/+ group (n=13) and a CT/- group (n=15), respectively. Two patients were excluded from the study preoperatively. There were no significant differences in age or laboratory findings, including liver function tests or the serum amylase level before or after surgery, between the two groups. In the CT/- group, endoscopic retrograde cholangiography-related pancreatitis developed in one patient, and one patient required conversion to open surgery. In contrast, in the CT/+ group, there were no preoperative complications and no patient required conversion to open surgery. The mean operative time was significantly shorter in the CT/+ group than in the CT/- group (P=0.0137). These findings provide evidence to support the advantages of helical CT cholangiography in relation to operative time, conversion, and procedure-related preoperative complications. (author)

  3. Bone changes of mandibular condyle using cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Un; Kim, Hyung Seop; Song, Ju Seop; Kim, Kyoung A; Koh, Kwang Joon [Chonbuk National Univ., Chonju (Korea, Republic of)

    2007-09-15

    To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibualr disorder (TMD) patients. 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra-and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Osteopathy (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior surface of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78{sub 0}.84), but interobserver agreement was fair (k=0.45). CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images.

  4. Computed Tomography Findings of Pulmonary Mycobacterium simiae Infection

    Science.gov (United States)

    Baghizadeh, Ayeh; Farnia, Poopak

    2017-01-01

    Nontuberculous mycobacterial (NTM) pulmonary infections can be quite similar to tuberculosis, both clinically and radiologically. However, the treatment protocol is not similar. Mycobacterium simiae is a rare cause of NTM pulmonary infection. Herein, we aimed to evaluate and compare the computed tomography (CT) scan findings of M. simiae infection in lungs. For this reason, thirty-four patients (n = 34) with M. simiae lung infection were retrospectively evaluated. Diagnosis was confirmed by American Thoracic Society (ATS) guidelines and CT scans were reviewed in both lung and mediastinal windows. The average age of patients was 63 ± 14.54 years and 52.9% were male. The majority of patients had cough (91.2%) and sputum production (76.5%). Clinically, 41.2% of patients had previous history of TB (14/34), 38.2% had cardiac diseases (13/34), and 35.3% had diabetes mellitus (12/34). The most common CT findings in our study were nodular lesions (100%) and bronchiectasis (85.29%). Regarding the severity, grade I bronchiectasis was the most prevalent. Other prominent findings were tree-in-bud sign (88.2%), consolidation (52.94%), and lobar fibrosis and volume loss (67.6%). There was no significant zonal distribution of findings. In conclusion, nodular lesions and bronchiectasis are the most frequent features in CT scan of M. simiae pulmonary infection.

  5. Continuous analog of multiplicative algebraic reconstruction technique for computed tomography

    Science.gov (United States)

    Tateishi, Kiyoko; Yamaguchi, Yusaku; Abou Al-Ola, Omar M.; Kojima, Takeshi; Yoshinaga, Tetsuya

    2016-03-01

    We propose a hybrid dynamical system as a continuous analog to the block-iterative multiplicative algebraic reconstruction technique (BI-MART), which is a well-known iterative image reconstruction algorithm for computed tomography. The hybrid system is described by a switched nonlinear system with a piecewise smooth vector field or differential equation and, for consistent inverse problems, the convergence of non-negatively constrained solutions to a globally stable equilibrium is guaranteed by the Lyapunov theorem. Namely, we can prove theoretically that a weighted Kullback-Leibler divergence measure can be a common Lyapunov function for the switched system. We show that discretizing the differential equation by using the first-order approximation (Euler's method) based on the geometric multiplicative calculus leads to the same iterative formula of the BI-MART with the scaling parameter as a time-step of numerical discretization. The present paper is the first to reveal that a kind of iterative image reconstruction algorithm is constructed by the discretization of a continuous-time dynamical system for solving tomographic inverse problems. Iterative algorithms with not only the Euler method but also the Runge-Kutta methods of lower-orders applied for discretizing the continuous-time system can be used for image reconstruction. A numerical example showing the characteristics of the discretized iterative methods is presented.

  6. Computed tomography: What and how does it measure?

    Science.gov (United States)

    Mazonakis, Michalis; Damilakis, John

    2016-08-01

    The current study provides a comprehensive review about the use and the clinical applications of computed tomography (CT) associated with the in vivo evaluation of the human body composition. The high-resolution CT images allow the accurate separation of the various body compartments at the tissue/organ level including adipose tissue, skeletal muscle, bones and organs. The further ability of the imaging modality to distinguish the cortical from the trabecular bone and the visceral from the susbcutaneous fat is of great value in clinical studies. CT may also give important information about the components of the subcutaneous adipose tissue and the muscle or liver fat infiltration. The efficient determination of the skeletal muscle attenuation and bone mineral density, that related with metabolic disorders, is feasible with the aid of CT data. The area and volume of each human body compartment may be estimated with high accuracy and reproducibility from CT scans. These estimations may be carried out using the methods of manual planimetry, semi-automatic segmentation of the tissue of interest, stereological point-counting approach and geometrical models based either on linear or area measurements. The advantages and disadvantages of the aforementioned methods for the quantification of the human body composition are presented and discussed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Predicting Neck Abscess with Contrast-Enhanced Computed Tomography

    Directory of Open Access Journals (Sweden)

    Melisa Lim Seer Yee

    2014-01-01

    Full Text Available Neck abscesses are difficult to diagnose and treat. Currently, contrast-enhanced computed tomography (CECT is the imaging modality of choice. The study aims to determine the predictive value of CECT findings in diagnosing neck abscess, causes of neck abscess and the most common neck space involved in the local population. 84 consecutive patients clinically suspected to have neck abscess who underwent CECT and surgical confirmation of pus were included. Demographic and clinical data were recorded. 75 patients were diagnosed as having neck abscess on CECT; out of those 71 patients were found to have pus. Overall CECT findings were found to have a high sensitivity (98.6% and positive predictive value (PPV (94.7% but lower specificity (67.2% in diagnosing neck abscess. The CECT diagnostic criterion with the highest PPV is the presence of rim irregularity (96%. The most common deep neck space involved is the submandibular compartment, which correlates with the finding that odontogenic cause was the most common identifiable cause of abscess in the study population. Thus, in a patient clinically suspected of having neck abscess, CECT findings of a hypodense mass with rim irregularity are helpful in confirming the diagnosis and guiding clinical management.

  8. Cone beam computed tomography findings of impacted upper canines

    Energy Technology Data Exchange (ETDEWEB)

    Da Silva Santos, Ludmilla Mota [Dept. of Endodontics, Aracatuba Dental School, Paulista State University, Aracatuba(Brazil); Bastos, Luana Costa; Da Silva, Silvio Jose Albergaria; Campos, Paulo Sergio Flores [School of Dentistry, Federal University of Bahia, Salvador (Brazil); Oliveira Santos, Christiano [Dept. of Stomatology, Oral Public Health, and Forensic Dentistry, School of Dentistry, University of Sao Paulo, Ribeirao Preto (Brazil); Neves, Frederico Sampaio [Dept. of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba (Brazil)

    2014-12-15

    To describe the features of impacted upper canines and their relationship with adjacent structures through three-dimensional cone-beam computed tomography (CBCT) images. Using the CBCT scans of 79 upper impacted canines, we evaluated the following parameters: gender, unilateral/bilateral occurrence, location, presence and degree of root resorption of adjacent teeth (mild, moderate, or severe), root dilaceration, dental follicle width, and presence of other associated local conditions. Most of the impacted canines were observed in females (56 cases), unilaterally (51 cases), and at a palatine location (53 cases). Root resorption in adjacent teeth and root dilaceration were observed in 55 and 47 impacted canines, respectively. In most of the cases, the width of the dental follicle of the canine was normal; it was abnormally wide in 20 cases. A statistically significant association was observed for all variables, except for root dilaceration (p=0.115) and the side of impaction (p=0.260). Root resorption of adjacent teeth was present in most cases of canine impaction, mostly affecting adjacent lateral incisors to a mild degree. A wide dental follicle of impacted canines was not associated with a higher incidence of external root resorption of adjacent teeth.

  9. Morphological analysis of the proximal femur using quantitative computed tomography

    Science.gov (United States)

    Jacobson, Donald; Carrera, Guilermo

    2006-01-01

    The anatomy of the proximal femur was studied in 35 specimens using quantitative computed tomography (QCT) and compared with anatomical sections studied by plane radiography and gross dissection. We found the primary supporting structure of the femoral head to be the primary compressive strut, which is a dense column of trabecular bone projecting from the pressure buttress of the medial femoral neck to the epiphyseal scar. Trabecular bone mushroomed from the epiphyseal scar and terminated at right angles to the cortex of the femoral head. We believe the primary compressive strut is the predominant load-bearing structure connecting the femoral head to the femoral neck, as many specimens lacked continuity of the head cortex to the femoral neck. Based on the CT number, the primary compressive strut had similar bone density to cortical structures such as the lesser trochanter, calcar femorale and posterior lateral femoral cortex. Ward’s triangle lacked structural integrity in many cases, and we doubt the significance of tensile trabculae for sharing load. Surgical techniques such as femoral fracture fixation, resurfacing hip arthroplasty and allograft transplantation may benefit from this knowledge. PMID:16896872

  10. Spatial smoothing coherence factor for ultrasound computed tomography

    Science.gov (United States)

    Lou, Cuijuan; Xu, Mengling; Ding, Mingyue; Yuchi, Ming

    2016-04-01

    In recent years, many research studies have been carried out on ultrasound computed tomography (USCT) for its application prospect in early diagnosis of breast cancer. This paper applies four kinds of coherence-factor-like beamforming methods to improve the image quality of synthetic aperture focusing method for USCT, including the coherence-factor (CF), the phase coherence factor (PCF), the sign coherence factor (SCF) and the spatial smoothing coherence factor (SSCF) (proposed in our previous work). The performance of these methods was tested with simulated raw data which were generated by the ultrasound simulation software PZFlex 2014. The simulated phantom was set to be water of 4cm diameter with three nylon objects of different diameters inside. The ring-type transducer had 72 elements with a center frequency of 1MHz. The results show that all the methods can reveal the biggest nylon circle with the radius of 2.5mm. SSCF gets the highest SNR among the proposed methods and provides a more homogenous background. None of these methods can reveal the two smaller nylon circles with the radius of 0.75mm and 0.25mm. This may be due to the small number of elements.

  11. Computed Tomography Appearance of Ovarian Fibrothecomas With and Without Torsion

    Energy Technology Data Exchange (ETDEWEB)

    Chee-Wai Mak; Wen-Sheng Tzeng; Chin-Yu Chen (Dept. of Diagnostic Imaging, Chi-Mei Medical Center, Yung Kang, Tainan, Taiwan (China))

    2009-06-15

    Background: Fibrothecomas are the most common solid ovarian tumors and may undergo torsion. Early diagnosis of these tumors is important in order to allow prompt surgical treatment. Purpose: To describe the features of ovarian fibrothecoma on computed tomography (CT) and to determine the possibility of detecting tumor torsion in this kind of tumor. Material and Methods: The CT images of 11 patients with ovarian fibrothecomas in the past 8 years at our hospital were retrospectively reviewed. The CT attenuation values of each tumor were measured in both non-enhanced and enhanced scans. The size and degree of enhancement were evaluated and correlated with tumor torsion. All cases were pathologically proven. Results: Three kinds of tumor pattern were found: 1) homogeneous tumor with significant enhancement containing scattered, low-attenuated regions after contrast injection; 2) heterogeneous tumor with mild enhancement after contrast injection; and 3) low-attenuated soft-tissue mass with no obvious enhancement after contrast injection. Conclusion: Fibrothecomas usually appear as a homogeneous solid tumor with varying degrees of enhancement. Calcification may be present and, as these tumors enlarge, myxoid or cystic degeneration may occur, resulting in a heterogeneous pattern. The larger the tumor, the greater is the chance of torsion. Lack of tumor enhancement is the most reliable sign for detection of ovarian torsion and should facilitate prompt surgical intervention to remove damaged tissue

  12. Thyroid lymphography-computed tomography (TLG-CT)

    Energy Technology Data Exchange (ETDEWEB)

    Matsuyama, Koukichi (Kansai Medical Univ., Moriguchi, Osaka (Japan))

    1992-10-01

    There are several useful diagnostic examinations for thyroid disease. The diagnostic value of CT in thyroid disease is still controvertial, although CT has become a routine clinical examination, since the plain CT does not always identify tumors accurately. In this paper, we introduce for the first time thyroid lymphography-computed tomography (TLG-CT) which may improve the diagnostic value of CT. The technique combines CT with thyroid lymphography. We performed TLG-CT in 92 patients with various thyroid diseases and 20 normal controls and classified the radiological features into the following 6 types: entire (normal thyroid); moth-eaten (Hashimoto's thyroiditis); defect (follicular adenoma and adenomatous goiter); lobate (papillary carcinoma); localized (various thyroid diseases); and extrathyroid defect (parathyroid tumor). In addition, we examined the relationship between TLG-CT type and the macroscopic appearance of the cut surface of the thyroid and lymph node metastasis in 20 patients with papillary carcinoma. The results suggest that papillary TLG-CT type carcinomas have a high incidence of lymph node metastasis. Our preliminary results suggest that TLG-CT is a potentially valuable diagnostic tool in the detection of thyroid disease and the assessment of the pathologic diagnosis as well as lymph node metastasis. (author).

  13. Kimura's disease: imaging patterns on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gopinathan, Anil [Department of Radiology, Changi General Hospital (Singapore)], E-mail: ivyanil10@gmail.com; Tan, T.Y. [Department of Radiology, Changi General Hospital (Singapore)

    2009-10-15

    Aim: To define the role of computed tomography (CT) in identifying and classifying the imaging patterns of diagnostic value in Kimura's disease of the head and neck. Methods: A retrospective study was undertaken comprising 13 patients with histopathological evidence of Kimura's disease. The patients' clinical and pathological records were reviewed against a detailed analysis of their CT images performed from the base of the skull to the arch of the aorta. Results: Both well-defined, nodular masses, as well as ill-defined plaque-like infiltrative masses were seen in the subcutaneous tissue of the head and neck region. All patients had lesions adjacent to the major salivary glands. The parotid gland was affected in 10 of the 13 cases and the submandibular gland was affected in the rest. Contrast enhancement was variable. More than half of the cases had associated lymphadenopathy. Some of them showed atrophy of the skin and subcutaneous fat overlying the subcutaneous masses. Blood eosinophilia was a consistent feature in all the cases. Conclusion: The patterns of distribution, morphology, and enhancement of the lesions in Kimura's disease that can be demonstrated at CT, enables a confident, non-invasive diagnosis of this condition, in an appropriate clinical context.

  14. X-ray computed tomography for additive manufacturing: a review

    Science.gov (United States)

    Thompson, A.; Maskery, I.; Leach, R. K.

    2016-07-01

    In this review, the use of x-ray computed tomography (XCT) is examined, identifying the requirement for volumetric dimensional measurements in industrial verification of additively manufactured (AM) parts. The XCT technology and AM processes are summarised, and their historical use is documented. The use of XCT and AM as tools for medical reverse engineering is discussed, and the transition of XCT from a tool used solely for imaging to a vital metrological instrument is documented. The current states of the combined technologies are then examined in detail, separated into porosity measurements and general dimensional measurements. In the conclusions of this review, the limitation of resolution on improvement of porosity measurements and the lack of research regarding the measurement of surface texture are identified as the primary barriers to ongoing adoption of XCT in AM. The limitations of both AM and XCT regarding slow speeds and high costs, when compared to other manufacturing and measurement techniques, are also noted as general barriers to continued adoption of XCT and AM.

  15. Additive Manufacturing of Anatomical Models from Computed Tomography Scan Data.

    Science.gov (United States)

    Gür, Y

    2014-12-01

    The purpose of the study presented here was to investigate the manufacturability of human anatomical models from Computed Tomography (CT) scan data via a 3D desktop printer which uses fused deposition modelling (FDM) technology. First, Digital Imaging and Communications in Medicine (DICOM) CT scan data were converted to 3D Standard Triangle Language (STL) format by using In Vaselius digital imaging program. Once this STL file is obtained, a 3D physical version of the anatomical model can be fabricated by a desktop 3D FDM printer. As a case study, a patient's skull CT scan data was considered, and a tangible version of the skull was manufactured by a 3D FDM desktop printer. During the 3D printing process, the skull was built using acrylonitrile-butadiene-styrene (ABS) co-polymer plastic. The printed model showed that the 3D FDM printing technology is able to fabricate anatomical models with high accuracy. As a result, the skull model can be used for preoperative surgical planning, medical training activities, implant design and simulation to show the potential of the FDM technology in medical field. It will also improve communication between medical stuff and patients. Current result indicates that a 3D desktop printer which uses FDM technology can be used to obtain accurate anatomical models.

  16. Frontal sinus parameters in computed tomography and sex determination.

    Science.gov (United States)

    Akhlaghi, Mitra; Bakhtavar, Khadijeh; Moarefdoost, Jhale; Kamali, Artin; Rafeifar, Shahram

    2016-03-01

    The frontal sinus is a sturdy part of the skull that is likely to be retrieved for forensic investigations. We evaluated frontal sinus parameters in paranasal sinus computed tomography (CT) images for sex determination. The study was conducted on 200 normal paranasal sinus CT images of 100 men and 100 women of Persian origin. We categorized the studied population into three age groups of 20-34, 35-49 and ⩾ 50 years. The number of partial septa in the right frontal sinus and the maximum height and width were significantly different between the two sexes. The highest precision for sex determination was for the maximum height of the left frontal sinus (61.3%). In the 20-34 years age-group, height and width of the frontal sinus were significantly different between the two sexes and the height of the left sinus had the highest precision (60.8%). In the 35-49 years age-group, right anterior-posterior diameter had a sex determination precision of 52.3%. No frontal sinus parameter reached a statistically significant level for sex determination in the ⩾ 50 years age-group. The number of septa and scallopings were not useful in sex determination. Frontal sinus parameters did not have a high precision in sex determination among Persian adults.

  17. Direct reconstruction of enhanced signal in computed tomography perfusion

    Science.gov (United States)

    Li, Bin; Lyu, Qingwen; Ma, Jianhua; Wang, Jing

    2016-04-01

    High imaging dose has been a concern in computed tomography perfusion (CTP) as repeated scans are performed at the same location of a patient. On the other hand, signal changes only occur at limited regions in CT acquired at different time points. In this work, we propose a new reconstruction strategy by effectively utilizing the initial phase high-quality CT to reconstruct the later phase CT acquired with a low-dose protocol. In the proposed strategy, initial high-quality CT is considered as a base image and enhanced signal (ES) is reconstructed directly by minimizing the penalized weighted least-square (PWLS) criterion. The proposed PWLS-ES strategy converts the conventional CT reconstruction into a sparse signal reconstruction problem. Digital and anthropomorphic phantom studies were performed to evaluate the performance of the proposed PWLS-ES strategy. Both phantom studies show that the proposed PWLS-ES method outperforms the standard iterative CT reconstruction algorithm based on the same PWLS criterion according to various quantitative metrics including root mean squared error (RMSE) and the universal quality index (UQI).

  18. Necrotic stercoral colitis: Importance of computed tomography findings

    Institute of Scientific and Technical Information of China (English)

    Cheng-Hsien Wu; Li-Jen Wang; Yon-Cheong Wong; Chen-Chih Huang; Chien-Cheng Chen; Chao-Jan Wang; Jen-Feng Fang; Chuen Hsueh

    2011-01-01

    AIM: To study the computed tomography (CT) signs in facilitating early diagnosis of necrotic stercoral colitis(NSC).METHODS: Ten patients with surgically and pathologically confirmed NSC were recruited from the Clinico-Pathologic-Radiologic conference at Chang Gung MemorialHospital, Taoyuan, Taiwan. Their CT images and medical records were reviewed retrospectively to correlate CT findings with clinical presentation.RESULTS: All these ten elderly patients with a mean age of 77.1 years presented with acute abdomen at our Emergency Room. Nine of them were with systemic medmedical disease and 8 with chronic constipation. Seven were with leukocytosis, two with low-grade fever, two with peritoneal sign, and three with hypotensive shock. Only one patient was with radiographic detected abnormal gas. Except the crux of fecal impaction, the frequency of the CT signs of NSC were, proximal colon dilatation (20%),colon wall thickening (60%), dense mucosa (62.5%),mucosal sloughing (10%), perfusion defect (70%),pericolonic stranding (80%), abnormal gas (50%) with pneumo-mesocolon (40%) in them, pericolonic abscess(20%). The most sensitive signs in decreasing order were pericolonic stranding, perfusion defect, dense mucosal,detecting about 80%, 70%, and 62.5% of the cases, respectively.CONCLUSION: Awareness of NSC and familiarity with the CT diagnostic signs enable the differential diagnosis between NSC and benign stool impaction.

  19. Dual-energy computed tomography for gout diagnosis and management.

    Science.gov (United States)

    Dalbeth, Nicola; Choi, Hyon K

    2013-01-01

    The central feature of gout is deposition of monosodium urate crystals. Dual-energy computed tomography (DECT) is a recently developed advanced imaging method that enables visualisation of urate deposits by analysis of the chemical composition of the scanned materials. This review summarises recent research describing the use of DECT in gout management. This technology may assist in both diagnosis and monitoring of the disease. Studies of patients with established disease indicate diagnostic accuracy for gout is high. Excellent inter-reader agreement has been reported for detection of urate deposits by use of DECT. Automated volume assessment software also enables rapid and reproducible measurement of urate deposits within tophi, suggesting that this modality may be useful for monitoring the disease. Although several case reports indicate DECT can be used to reveal reduction in the size of urate deposits, the sensitivity to change in response to urate-lowering therapy has not yet been systematically reported. DECT images reveal variable urate deposition within tophi of the same physical size. The ability to visualise urate deposits in tissue may provide new insights into the pathology and mechanisms of gout.

  20. Computed tomographies of chronic schizophrenic patients following prefrontal lobotomy

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Masahiko; Ogihara, Ryuji; Suzuki, Jiro

    1984-08-01

    To evaluate the long-term effects of prefrontal lobotomy, 70 chronic schizophrenic patients (male, 42; female, 28) who had undergone prefrontal lobotomy at the Tokyo Metropolitan Matsuzawa Hospital more than 25 years ago were studied by means of computed tomography (CT). The age of the subjects ranged from 51 to 83, averaging 63.9. All CT scans were performed with GE-CT/T. Cuts were made parallel to the orbito-meatal line at 10-mm intervals in all patients. CT scans of the coronal section were also obtained in some patients. There are 9 methods of lobotomy. Standard lobotomy and orbital lobotomy were most frequently found in our subjects. Corresponding to the lobotomy sites in the white matter of the frontal lobe, well-defined low-density areas were demonstrated in all the patients. The attenuation of these areas was identical with that of the cerebrospinal fluid. The location and the extent of these low-density areas were characteristic of each method of lobotomy. Except in the frontal lobe, there were no significant changes in the cerebrum compared with those of the non-lobotomized chronic schizophrenic patients who were selected as controls. (author).

  1. Basilar artery occlusion: Prognostic signs of severity on computed tomography.

    Science.gov (United States)

    Poletti, Pierre-Alexandre; Pereira, Vitor Mendes; Lovblad, Karl-Olof; Canel, Lucie; Sztajzel, Roman; Becker, Minerva; Perneger, Thomas; Platon, Alexandra

    2015-07-01

    To determine the computed tomography (CT) signs that are predictive of the clinical outcome of basilar artery occlusion (BAO). The study population consisted in 37 patients (14 women, 23 men, mean age: 63 years), admitted with onset of neurological deficit, starting 1-72 h prior to admission, who were diagnosed with BAO on the basis of a CT examination with intravenous contrast agent. The following signs were collected on CT scans performed on admission: clot density on noncontrast images, clot length, and clot location, as well as the presence of acute ischemic lesions. The results were compared against the modified Rankin Scale (mRS) score of patients at 3 months, favorable clinical outcome being defined as a mRS score ≤3. The clinical outcome was favorable in 13 (35%) of the 37 patients and unfavorable in 24 (65%). Signs of acute ischemia were visible in 13 of the 24 patients with unfavorable outcome but in none of the 13 patients with favorable outcome (p<0.001). None of the other CT signs analyzed were significantly correlated with clinical prognosis. Of all the CT signs analyzed, only the presence of signs of acute ischemia on the admission CT of patients with BAO was associated with poor prognosis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Emergency Computed Tomography: What is Missed at First Reading?

    Science.gov (United States)

    Platon, Alexandra; Becker, Minerva; Perneger, Thomas; Varnay, Gyorgi; Breguet, Romain; Becker, Christoph D; Poletti, Pierre-Alexandre

    2016-01-01

    The aim of this study was to evaluate the accuracy of preliminary computed tomography (CT) interpretations made by radiology residents in the emergency department. For 4 periods of 20 consecutive days, attending radiologists prospectively recorded any disparities between their own CT interpretations (reference standard) and the preliminary interpretations of emergency radiology residents. Misinterpretations were defined as major when related to a potentially life-threatening pathology if not immediately managed after CT. The rate of disparities was calculated for all CT examinations, separately for body and neuroradiological cases, and for working and on-call hours. A total of 3044 emergency CT examinations were performed during the survey: 1568 (51%) body scans and 1476 (49%) neurological scans. Disparities were reported in 145 (4.8%) of all CT examinations, with 0.8% (24/3044) defined as major misinterpretations. There were 100 (6.3%) of 1568 disparities in body CT versus 45 (3.0%) of 1476 in neurological CT examinations (P = 0.001). No significant differences were found between disparities recorded during regular working hours (47/1083 [4.3%]) versus on-call hours (98/1961 [5.0%], P = 0.47). There were typically more disparities between resident and attending interpretations in emergency body CT. Major disparities represented only a small proportion of all misinterpretations. The detailed analysis of our data enables benchmarking over time and offers a reference for optimizing the training of residents in emergency radiology.

  3. Hepatic angiomyolipoma: Dynamic computed tomography features and clinical correlation

    Institute of Scientific and Technical Information of China (English)

    Bin Yang; Wen-Hui Chen; Qiao-Yun Li; Jing-Jing Xiang; Ru-Jun Xu

    2009-01-01

    AIM: To study the dynamic computed tomography (CT) features of hepatic angiomyolipoma (AML) in patients with or without tuberous sclerosis complex (TSC). METHODS: The clinical information, CT findings and histopathological results of hepatic AML were analyzed retrospectively in 10 patients. RESULTS: Hepatic AML was prone to occur in female patients (7/10), and most of the patients (8/10) had no specific symptoms. All tumors presented as welldefined, unenveloped nodules in the liver. Six patients with sporadic hepatic AML had a solitary hepatic nodule with a definite fat component. Non-fat components of the hepatic lesions were enhanced earlier and persistently. Prominent central vessels were noted in the portal venous phase in three patients. In four patients with hepatic AML and TSC, most of the nodules were within the peripheral liver. Seven fatdeficient nodules were found with earlier contrast enhancement and rapid contrast material washout in two patients. Lymphangioleiomyomatosis was found in one patient.CONCLUSION: Imaging features of hepatic AML are characteristic. Correct diagnosis preoperatively can be made in combination with clinical features.

  4. Reproducibility of aortic annulus measurements by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Schuhbaeck, Annika; Achenbach, Stephan [University of Erlangen, Department of Cardiology, Erlangen (Germany); University of Giessen, Department of Cardiology, Giessen (Germany); Pflederer, Tobias; Marwan, Mohamed; Schmid, Jasmin; Arnold, Martin [University of Erlangen, Department of Cardiology, Erlangen (Germany); Nef, Holger; Rixe, Johannes; Hecker, Franziska [University of Giessen, Department of Cardiology, Giessen (Germany); Schneider, Christian [University of Giessen, Department of Radiology, Giessen (Germany); Lell, Michael; Uder, Michael [University of Erlangen, Department of Radiology, Erlangen (Germany)

    2014-08-15

    To evaluate a systematic approach for measurement of aortic annulus dimensions by cardiac computed tomography. CT data sets of 64 patients were evaluated. An oblique cross-section aligned with the aortic root was created by systematically identifying the caudal insertion points of the three aortic cusps and sequentially aligning them in a double oblique plane. Aortic annulus dimensions, distances of coronary ostia and a suitable fluoroscopic projection angle were independently determined by two observers. Interobserver intraclass correlation coefficients (ICC) for aortic annulus diameters were excellent (ICC 0.89-0.93). Agreement for prosthesis size selection was excellent (k = 0.86 for mean, k = 0.84 for area-derived and k = 0.91 for circumference-derived diameter). Mean distances of the left/right coronary ostium were 13.4 ± 2.4/14.4 ± 2.8 mm for observer 1 and 13.2 ± 2.7/13.5 ± 3.2 mm for observer 2 (p = 0.30 and p = 0.0001, respectively; ICC 0.76/0.77 for left/right coronary artery). A difference of less than 10 for fluoroscopic projection angle was achieved in 84.3 % of patients. A systematic approach to generate a double oblique imaging plane exactly aligned with the aortic annulus demonstrates high interobserver and intraobserver agreements for derived measurements which are not influenced by aortic root calcification. (orig.)

  5. [Diagnosis. Radiological study. Ultrasound, computed tomography and magnetic resonance imaging].

    Science.gov (United States)

    Gallo Vallejo, Francisco Javier; Giner Ruiz, Vicente

    2014-01-01

    Because of its low cost, availability in primary care and ease of interpretation, simple X-ray should be the first-line imaging technique used by family physicians for the diagnosis and/or follow-up of patients with osteoarthritis. Nevertheless, this technique should only be used if there are sound indications and if the results will influence decision-making. Despite the increase of indications in patients with rheumatological disease, the role of ultrasound in patients with osteoarthritis continues to be limited. Computed tomography (CT) is of some -although limited- use in osteoarthritis, especially in the study of complex joints (such as the sacroiliac joint and facet joints). Magnetic resonance imaging (MRI) has represented a major advance in the evaluation of joint cartilage and subchondral bone in patients with osteoarthritis but, because of its high cost and diagnostic-prognostic yield, this technique should only be used in highly selected patients. The indications for ultrasound, CT and MRI in patients with osteoarthritis continue to be limited in primary care and often coincide with situations in which the patient may require hospital referral. Patient safety should be bourne in mind. Patients should be protected from excessive ionizing radiation due to unnecessary repeat X-rays or inadequate views or to requests for tests such as CT, when not indicated. Copyright © 2014 Elsevier España, S.L. All rights reserved.

  6. Classification of bifid mandibular canals using cone beam computed tomography

    Directory of Open Access Journals (Sweden)

    Gisele Maria Correr

    2013-12-01

    Full Text Available The objective of this study was to classify the morphology of bifid mandibular canals and to evaluate their relationship with the roots of third molars, using cone beam computed tomography (CBCT scans. The CBCT scans of 75 patients were analyzed and the bifurcations were classified according to Langlais et al. (1985. The relationship of bifurcation and third molars was established according to the following classification: class A - uninvolved, class B - close relationship, class C - intimate relationship and class D - absence of third molars. Data were submitted to descriptive statistics, and the results indicated that the patients' mean age was 48.2 (± 13.2 years. Unilateral bifurcation (Type 1 was the most frequent type (72.6%, followed by unilateral Type 2 (19.3%. Class D was the most frequent (57.33%, followed by class C (21.33%, class B (13.33% and class A (8%. It could be concluded that most cases presented unilateral bifid mandibular canals extending to the third molar or adjacent regions, and when present, the roots seemed to be a continuation of the bifid mandibular canal

  7. Pulmonary high-resolution computed tomography findings in nephropathia epidemica

    Energy Technology Data Exchange (ETDEWEB)

    Paakkala, Antti, E-mail: antti.paakkala@pshp.fi [Medical Imaging Centre, Tampere University Hospital, 33521 Tampere (Finland); Jaervenpaeae, Ritva, E-mail: ritva.jarvenpaa@pshp.fi [Medical Imaging Centre, Tampere University Hospital, 33521 Tampere (Finland); Maekelae, Satu, E-mail: satu.marjo.makela@uta.fi [Department of Internal Medicine, Tampere University Hospital, 33521 Tampere (Finland); Medical School, University of Tampere, 33521 Tampere (Finland); Huhtala, Heini, E-mail: heini.huhtala@uta.fi [School of Public Health, University of Tampere, 33521 Tampere (Finland); Mustonen, Jukka, E-mail: jukka.mustonen@uta.fi [Department of Internal Medicine, Tampere University Hospital, 33521 Tampere (Finland); Medical School, University of Tampere, 33521 Tampere (Finland)

    2012-08-15

    Purpose: To evaluate lung high-resolution computed tomography (HRCT) findings in patients with Puumala hantavirus-induced nephropathia epidemica (NE), and to determine if these findings correspond to chest radiograph findings. Materials and methods: HRCT findings and clinical course were studied in 13 hospital-treated NE patients. Chest radiograph findings were studied in 12 of them. Results: Twelve patients (92%) showed lung parenchymal abnormalities in HRCT, while only 8 had changes in their chest radiography. Atelectasis, pleural effusion, intralobular and interlobular septal thickening were the most common HRCT findings. Ground-glass opacification (GGO) was seen in 4 and hilar and mediastinal lymphadenopathy in 3 patients. Atelectasis and pleural effusion were also mostly seen in chest radiographs, other findings only in HRCT. Conclusion: Almost every NE patient showed lung parenchymal abnormalities in HRCT. The most common findings of lung involvement in NE can be defined as accumulation of pleural fluid and atelectasis and intralobular and interlobular septal thickening, most profusely in the lower parts of the lung. As a novel finding, lymphadenopathy was seen in a minority, probably related to capillary leakage and overall fluid overload. Pleural effusion is not the prominent feature in other viral pneumonias, whereas intralobular and interlobular septal thickening are characteristic of other viral pulmonary infections as well. Lung parenchymal findings in HRCT can thus be taken not to be disease-specific in NE and HRCT is useful only for scientific purposes.

  8. Computed tomography of the thymus in myasthenia gravis

    Energy Technology Data Exchange (ETDEWEB)

    Tanimura, Shigeo; Sakaguchi, Kozo; Tomoyasu, Hiroshi; Banba, Jiro; Masaki, Mikio; Kurosaki, Atsuko; Matsushita, Hisashi [Toranomon Hospital, Tokyo (Japan)

    1995-01-01

    Comparison of preoperative CT diagnosis and histopathological diagnosis for the thymus were studied in 39 patients with myasthenia gravis. The patients consisted of 10 patients with thymoma and 29 without thymoma confirmed at the operation. CT diagnosis was 11 thymomas, 18 thymic hyperplasias and 10 normal thymuses. Eleven thymomas revealed histopathologically 9 thymomas, one follicular lymphoid hyperplasia (FLH) and one involved thymus. Out of 18 thymic hyperplasias 15 cases were FLH and 3 involved thymus. There were 5 involved thymuses, 4 FLHs and one thymoma in the 10 normal thymuses on CT. The finding of `reticular pattern`, many small nodules scattered reticularly in the thymus, in computed tomography could be regarded as a sign suggesting FLH of the thymus. The accuracy of this finding of CT was 83% for FLH. The finding of thymoma on CT revealed 82% of the accuracy. Therefore, CT was very useful in the diagnosis of the localization of the thymoma but not for the diagnosis of FLH of the thymus. Nevertheless the finding of `reticular pattern` on CT was helpful in the diagnosis of FLH. (author).

  9. Computed tomography of tumors of paranasal sinuses and face

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sun Wha [Kyung Hee University College of Medicine, Seoul (Korea, Republic of)

    1982-09-15

    The computed tomography can image both bone and soft tissue structures of paranasal sinuses and face and so CT has added an important new dimension to radiological evaluation of disease of paranasal sinuses and face. CT is more accurate method of staging of tumors and essential for therapeutic planning. The author studied 25 cases of proven tumors of paranasal sinuses and face during the period from October 1977 to August 1980 in Kyung Hee University Hospital. The results were as follows: 1. Among 14 females and 11 male, their age range was from 14 years to 65 year. 2. The distribution of tumors were mucocele, squamous cell carcinoma, metastatic carcinoma, meningioma, angiofibroma, Masson's hemangiosarcoma, fibrous dysplasia, neurogenic sarcoma, Schwannoma, hemangioma, epidermoid, transitional cell carcinoma and unknown. 3. Determination of location and extent of mucocele was easily done by CT. Thus in all cases of ethmoid mucocele, chief complaint of exophthalmos could be easily explained by identification of its extension into peripheral fat space of orbit. 4. It is our belief that CT was useful method to determine staging of tumors of paranasal sinuses and was essential in choosing appropriate treatment modality. 5. The contrast enhancement is generally not helpful in pathologic diagnosis of tumors but intracranial extension of tumors are clearly defined by contrast enhancement.

  10. The application of computed tomography in wound ballistics research

    Science.gov (United States)

    Tsiatis, Nick; Moraitis, Konstantinos; Papadodima, Stavroula; Spiliopoulou, Chara; Kelekis, Alexis; Kelesis, Christos; Efstathopoulos, Efstathios; Kordolaimi, Sofia; Ploussi, Agapi

    2015-09-01

    In wound ballistics research there is a relationship between the data that characterize a bullet and the injury resulted after shooting when it perforates the human body. The bullet path in the human body following skin perforation as well as the damaging effect cannot always be predictable as they depend on various factors such as the bullet's characteristics (velocity, distance, type of firearm and so on) and the tissue types that the bullet passes through. The purpose of this presentation is to highlight the contribution of Computed Tomography (CT) in wound ballistics research. Using CT technology and studying virtual “slices” of specific areas on scanned human bodies, allows the evaluation of density and thickness of the skin, the subcutaneous tissue, the muscles, the vital organs and the bones. Density data taken from Hounsfield units can be converted in g/ml by using the appropriate software. By evaluating the results of this study, the anatomy of the human body utilizing ballistic gel will be reproduced in order to simulate the path that a bullet follows. The biophysical analysis in wound ballistics provides another application of CT technology, which is commonly used for diagnostic and therapeutic purposes in various medical disciplines.

  11. Digital Radiography and Computed Tomography (DRCT) Product Improvement Plan (PIP)

    Energy Technology Data Exchange (ETDEWEB)

    Tim Roney; Bob Pink; Karen Wendt; Robert Seifert; Mike Smith

    2010-12-01

    The Idaho National Laboratory (INL) has been developing and deploying x-ray inspection systems for chemical weapons containers for the past 12 years under the direction of the Project Manager for Non-Stockpile Chemical Materiel (PMNSCM). In FY-10 funding was provided to advance the capabilities of these systems through the DRCT (Digital Radiography and Computed Tomography) Product Improvement Plan (PIP), funded by the PMNSCM. The DRCT PIP identified three research tasks; end user study, detector evaluation and DRCT/PINS integration. Work commenced in February, 2010. Due to the late start and the schedule for field inspection of munitions at various sites, it was not possible to spend sufficient field time with operators to develop a complete end user study. We were able to interact with several operators, principally Mr. Mike Rowan who provided substantial useful input through several discussions and development of a set of field notes from the Pueblo, CO field mission. We will be pursuing ongoing interactions with field personnel as opportunities arise in FY-11.

  12. Computed tomography in the imaging of colonic diverticulitis

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, O.; Geoghegan, T.; O' Riordain, D.S.; Lyburn, I.D.; Torreggiani, W.C. E-mail: william.torreggiani@amnch.ie

    2004-11-01

    Colonic diverticulitis occurs when diverticula within the colon become infected or inflamed. It is becoming an increasingly common cause for hospital admission, particularly in western society, where it is linked to a low fibre diet. Symptoms of diverticulitis include abdominal pain, diarrhoea and pyrexia, however, symptoms are often non-specific and the clinical diagnosis may be difficult. In addition, elderly patients and those taking corticosteroids may have limited findings on physical examination, even in the presence of severe diverticulitis. A high index of suspicion is required in such patients in order to avoid a significant delay in arriving at the correct diagnosis. Imaging plays an important role in establishing an early and correct diagnosis. In the past, contrast enema studies were the principal imaging test used to make the diagnosis. However, such studies lack sensitivity and have limited success in identifying abscesses that may require drainage. Conversely computed tomography (CT) is both sensitive and specific in making a diagnosis of diverticulitis. In addition, it is the imaging technique of choice in depicting complications such as perforation, abscess formation and fistulae. CT-guided drainage of diverticular abscesses helps to reduce sepsis and to permit a one-stage, rather than two-stage, surgical operation. The purpose of this review article is to discuss the role of CT in the imaging of diverticulitis, describe the CT imaging features and complications of this disease, as well as review the impact and rationale of CT imaging and intervention in the overall management of patients with diverticulitis.

  13. Examination of the osteoarthritic hips by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tajiri, Masahiro; Hieda, Hiroshi (Kurume Univ., Fukuoka (Japan). School of Medicine)

    1982-06-01

    Sixteen normal hips in 8 persons and 29 osteoarthritic hips in 19 patients were examined by a computed tomography (CT), calculating CT value of the femoral head and acetabulum. Atrophy of muscles around the hip joints was also measured on CT by planimeter. The results obtained were as follows: 1. The mean CT value of the normal femoral head was 238 +- 8.6 (H. U.) and that of the acetabulum was 199 +- 2.8. 2. The mean CT value of the osteoarthritic femoral head increased in accordance with degenerative stage, reaching to the maximum value of 351 +- 6.8 at the progressive stage, while it decreased to 285 +- 21.3 at the late stage. 3. The mean CT value of the acetabulum showed a high score of 285 +- 21.3 already at the early stage and remained stationary. 4. Atrophy of the gluteus medius muscle was observed at early stage; the gluteus maximus muscle at the progressive stage, and the tensor fasciae latae, gluteus minimus and iliopsoas muscle at the late stage.

  14. Brain single photon emission computed tomography in neonates

    Energy Technology Data Exchange (ETDEWEB)

    Denays, R.; Van Pachterbeke, T.; Tondeur, M.; Spehl, M.; Toppet, V.; Ham, H.; Piepsz, A.; Rubinstein, M.; Nol, P.H.; Haumont, D. (Free Universities of Brussels (Belgium))

    1989-08-01

    This study was designed to rate the clinical value of ({sup 123}I)iodoamphetamine (IMP) or ({sup 99m}Tc) hexamethyl propylene amine oxyme (HM-PAO) brain single photon emission computed tomography (SPECT) in neonates, especially in those likely to develop cerebral palsy. The results showed that SPECT abnormalities were congruent in most cases with structural lesions demonstrated by ultrasonography. However, mild bilateral ventricular dilatation and bilateral subependymal porencephalic cysts diagnosed by ultrasound were not associated with an abnormal SPECT finding. In contrast, some cortical periventricular and sylvian lesions and all the parasagittal lesions well visualized in SPECT studies were not diagnosed by ultrasound scans. In neonates with subependymal and/or intraventricular hemorrhage the existence of a parenchymal abnormality was only diagnosed by SPECT. These results indicate that ({sup 123}I)IMP or ({sup 99m}Tc)HM-PAO brain SPECT shows a potential clinical value as the neurodevelopmental outcome is clearly related to the site, the extent, and the number of cerebral lesions. Long-term clinical follow-up is, however, mandatory in order to define which SPECT abnormality is associated with neurologic deficit.

  15. Coronary revascularization treatment based on dual-source computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Dikkers, R.; Willems, T.P.; Jonge, G.J. de; Zaag-Loonen, H.J. van der; Ooijen, P.M.A. van; Oudkerk, M. [University of Groningen, Department of Radiology, Groningen (Netherlands); University Medical Center, Groningen (Netherlands); Piers, L.H.; Tio, R.A.; Zijlstra, F. [University of Groningen, Department of Cardiology, Groningen (Netherlands); University Medical Center, Groningen (Netherlands)

    2008-09-15

    Therapy advice based on dual-source computed tomography (DSCT) in comparison with coronary angiography (CAG) was investigated and the results evaluated after 1-year follow-up. Thirty-three consecutive patients (mean age 61.9 years) underwent DSCT and CAG and were evaluated independently. In an expert reading (the ''gold standard''), CAG and DSCT examinations were evaluated simultaneously by an experienced radiologist and cardiologist. Based on the presence of significant stenosis and current guidelines, therapy advice was given by all readers blinded from the results of other readings and clinical information. Patients were treated based on a multidisciplinary team evaluation including all clinical information. In comparison with the gold standard, CAG had a higher specificity (91%) and positive predictive value (PPV) (95%) compared with DSCT (82% and 91%, respectively). DSCT had a higher sensitivity (96%) and negative predictive value (NPV) (89%) compared with CAG (91% and 83%, respectively). The DSCT-based therapy advice did not lead to any patient being denied the revascularization they needed according to the multidisciplinary team evaluation. During follow-up, two patients needed additional revascularization. The high NPV for DSCT for revascularization assessment indicates that DSCT could be safely used to select patients benefiting from medical therapy only. (orig.)

  16. Oblique reconstruction of the cruciate ligaments on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ihara, Hidetoshi; Nishino, Koshi; Koga, Masayuki; Kitakata, Akira; Deya, Keizo; Nakagawa, Hiroto

    1984-12-01

    Optimal positioning where the entire longitudinal axis of the cruciate ligaments could be demonstrated on computed tomography was discovered by using an amputated knee and was applied clinically. To demonstrate the anterior cruciate ligament, the patient was positioned on the table with the hip flexed, abducted, externally rotated and knee flexed at a 110-140 degrees angle. For the posterior cruciate ligament, the patient was placed in a prone position on the table with the knee flexed at a 50 degrees angle. These positions, especially the one for the anterior cruciate ligament, were difficult for some patients with gonalgia or limited range of motion. Reconstruction in the oblique planes was studied for those patients by using an amputated knee and quasi-ligament made of gum. Clinically, an axial image was obtained by the simple position of the patient lying prone on the table with knee extended. Oblique reconstruction was made from the axial images and this reconstructed image also demonstrated the entire longitudinal axis of the ligament. The rupture of the cruciate ligaments could be assessed by the reconstructed image in the oblique plane. (author).

  17. Soft tissue discrimination ex vivo by dual energy computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Zachrisson, H., E-mail: helene.zachrisson@lio.s [Center for Medical Image Science and Visualization, Linkoeping University, Linkoeping University Hospital, SE-581 85 Linkoeping (Sweden); Clinical Physiology, Department of Medical and Health Sciences (IMH), Linkoeping University, Linkoeping University Hospital, SE-581 85 Linkoeping (Sweden); Engstroem, E. [Clinical Physiology, Department of Medical and Health Sciences (IMH), Linkoeping University, Linkoeping University Hospital, SE-581 85 Linkoeping (Sweden); Engvall, J.; Wigstroem, L. [Center for Medical Image Science and Visualization, Linkoeping University, Linkoeping University Hospital, SE-581 85 Linkoeping (Sweden); Clinical Physiology, Department of Medical and Health Sciences (IMH), Linkoeping University, Linkoeping University Hospital, SE-581 85 Linkoeping (Sweden); Smedby, O.; Persson, A. [Center for Medical Image Science and Visualization, Linkoeping University, Linkoeping University Hospital, SE-581 85 Linkoeping (Sweden); Radiology, Department of Medical and Health Sciences (IMH), Linkoeping University, Linkoeping University Hospital, SE-581 85 Linkoeping (Sweden)

    2010-08-15

    Purpose: Dual Energy Computed Tomography (DECT) may provide additional information about the chemical composition of tissues compared to examination with a single X-ray energy. The aim of this in vitro study was to test whether combining two energies may significantly improve the detection of soft tissue components commonly present in arterial plaques. Methods: Tissue samples of myocardial and psoas muscle, venous and arterial thrombus as well as fat from different locations were scanned using a SOMATOM Definition Dual Source CT system (Siemens AG, Medical Solutions, Forchheim, Germany) with simultaneous tube voltages of 140 and 80 kV. The attenuation (Hounsfield units, HU) at 80 and 140 kV was measured in representative regions of interest, and the association between measured HU values and tissue types was tested with logistic regression. Results: The combination of two energy levels (80 and 140 kV) significantly improved (p < 0.001) the ability to correctly classify venous thrombus vs arterial thrombus, myocardium or psoas; arterial thrombus vs myocardium or psoas; myocardium vs psoas; as well as the differentiation between fat tissue from various locations. Single energy alone was sufficient for distinguishing fat from other tissues. Conclusion: DECT offers significantly improved in vitro differentiation between soft tissues occurring in plaques. If this corresponds to better tissue discrimination in vivo needs to be clarified in future studies.

  18. Computed tomography: acquisition process, technology and current state

    Directory of Open Access Journals (Sweden)

    Óscar Javier Espitia Mendoza

    2016-02-01

    Full Text Available Computed tomography is a noninvasive scan technique widely applied in areas such as medicine, industry, and geology. This technique allows the three-dimensional reconstruction of the internal structure of an object which is lighted with an X-rays source. The reconstruction is formed with two-dimensional cross-sectional images of the object. Each cross-sectional is obtained from measurements of physical phenomena, such as attenuation, dispersion, and diffraction of X-rays, as result of their interaction with the object. In general, measurements acquisition is performed with methods based on any of these phenomena and according to various architectures classified in generations. Furthermore, in response to the need to simulate acquisition systems for CT, software dedicated to this task has been developed. The objective of this research is to determine the current state of CT techniques, for this, a review of methods, different architectures used for the acquisition and some of its applications is presented. Additionally, results of simulations are presented. The main contributions of this work are the detailed description of acquisition methods and the presentation of the possible trends of the technique.

  19. Computed tomography perfusion imaging denoising using Gaussian process regression

    Science.gov (United States)

    Zhu, Fan; Carpenter, Trevor; Rodriguez Gonzalez, David; Atkinson, Malcolm; Wardlaw, Joanna

    2012-06-01

    Brain perfusion weighted images acquired using dynamic contrast studies have an important clinical role in acute stroke diagnosis and treatment decisions. However, computed tomography (CT) images suffer from low contrast-to-noise ratios (CNR) as a consequence of the limitation of the exposure to radiation of the patient. As a consequence, the developments of methods for improving the CNR are valuable. The majority of existing approaches for denoising CT images are optimized for 3D (spatial) information, including spatial decimation (spatially weighted mean filters) and techniques based on wavelet and curvelet transforms. However, perfusion imaging data is 4D as it also contains temporal information. Our approach using Gaussian process regression (GPR), which takes advantage of the temporal information, to reduce the noise level. Over the entire image, GPR gains a 99% CNR improvement over the raw images and also improves the quality of haemodynamic maps allowing a better identification of edges and detailed information. At the level of individual voxel, GPR provides a stable baseline, helps us to identify key parameters from tissue time-concentration curves and reduces the oscillations in the curve. GPR is superior to the comparable techniques used in this study.

  20. A framework of modeling detector systems for computed tomography simulations

    Science.gov (United States)

    Youn, H.; Kim, D.; Kim, S. H.; Kam, S.; Jeon, H.; Nam, J.; Kim, H. K.

    2016-01-01

    Ultimate development in computed tomography (CT) technology may be a system that can provide images with excellent lesion conspicuity with the patient dose as low as possible. Imaging simulation tools have been cost-effectively used for these developments and will continue. For a more accurate and realistic imaging simulation, the signal and noise propagation through a CT detector system has been modeled in this study using the cascaded linear-systems theory. The simulation results are validated in comparisons with the measured results using a laboratory flat-panel micro-CT system. Although the image noise obtained from the simulations at higher exposures is slightly smaller than that obtained from the measurements, the difference between them is reasonably acceptable. According to the simulation results for various exposure levels and additive electronic noise levels, x-ray quantum noise is more dominant than the additive electronic noise. The framework of modeling a CT detector system suggested in this study will be helpful for the development of an accurate and realistic projection simulation model.