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Sample records for multidetector-row computed tomography

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

    African Journals Online (AJOL)

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

  2. Multi-detector row computed tomography and blunt chest trauma

    International Nuclear Information System (INIS)

    Scaglione, Mariano; Pinto, Antonio; Pedrosa, Ivan; Sparano, Amelia; Romano, Luigia

    2008-01-01

    Blunt chest trauma is a significant source of morbidity and mortality in industrialized countries. The clinical presentation of trauma patients varies widely from one individual to another and ranges from minor reports of pain to shock. Knowledge of the mechanism of injury, the time of injury, estimates of motor vehicle accident velocity and deceleration, and evidence of associated injury to other systems are all salient features to provide for an adequate assessment of chest trauma. Multi-detector row computed tomography (MDCT) scanning and MDCT-angiography are being used more frequently in the diagnosis of patients with chest trauma. The high sensitivity of MDCT has increased the recognized spectrum of injuries. This new technology can be regarded as an extremely valuable adjunct to physical examination to recognize suspected and unsuspected blunt chest trauma

  3. Multidetector-row computed tomography management of acute pulmonary embolism

    International Nuclear Information System (INIS)

    Yasui, Takahiro; Tanabe, Nobuhiro; Terada, Jiro

    2007-01-01

    The purpose of this study was to evaluate the usefulness and safety of multidetector-row computed tomography (MDCT) pulmonary angiography and indirect venography management of acute pulmonary embolism (PE), including indication for inferior vena cava (IVC) filter. Seventy-one consecutive patients who were clinically suspected of PE and underwent 16-slice MDCT pulmonary angiography and indirect venography were enrolled. Management included indication of IVC filter for patients with extensive deep venous thrombosis (DVT) in submassive or massive PE. A right ventricular to left ventricular short-axis diameter by MDCT >1.0 was judged as submassive PE. All patients were followed for 1 year. MDCT identified 50 patients with venous thromboembolism and 47 patients had acute PE: 4 were judged as massive, 14 as submassive, and 29 as non-massive by MDCT; 3 patients had DVT alone and 7 patients had caval or iliac DVT. Only 1 patient with massive PE and DVT near the right atrium died of recurrence. No other patients died of PE. Management based on MDCT pulmonary angiography combined with indirect venography is considered to be safe and reliable in patients with suspected acute PE. (author)

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

    International Nuclear Information System (INIS)

    Imagawa, Hiroshi; Kawachi, Kanji; Takano, Shinji

    2005-01-01

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

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  6. Prevalence and Characteristics of Myocardial Bridging in Multidetector-Row Computed Tomography Coronary Angiography

    International Nuclear Information System (INIS)

    Carrascosa, Patricia; Martin Lopez, Elba; Capunay, Carlos; Deviggiano, Alejandro; Vallejos, Javier; Carrascosa, Jorge

    2009-01-01

    Background: Myocardial bridging (MB) are congenital defects of the coronary arteries in which a segment of an epicardial artery lies in the myocardium for part of its course. The current gold standard for diagnosing MB is coronary angiography; however other invasive techniques are also useful. Myocardial bridging can also be visualized with the use of novel non-invasive imaging techniques such as multidetector-row computed tomography coronary angiography (MDCT-CA). Objectives: To assess the prevalence and characteristics of myocardial bridging in patients undergoing multidetector-row computed tomography coronary angiography (MDCT-CA). Material and Methods: A total of 452 consecutive patients were evaluated with 16-row and 64-row MDCT-CA due to the presence of abnormal findings in myocardial perfusion image tests, symptoms suggestive of coronary artery disease, and in asymptomatic patients with a family history of coronary artery disease. The presence of MB, their location and characteristics were analyzed. Myocardial bridging were classified as complete and incomplete bridges with respect to continuity of the myocardium over the tunneled segment of the artery involved. Quantitative measurements of vessel diameter during systole and diastole were evaluated. Results: The prevalence of MB was 35.18%; 88 were complete and 71 incomplete. Among complete MB, 6 affected both systole and diastole, 27 presented only systolic compression and 55 showed no compression. Incomplete MB showed absence of arterial compression. Conclusions: Multidetector-row computed tomography coronary angiography detected a higher prevalence of MB in the study population and allowed to classify them and to assess their functional aspects throughout the cardiac cycle. (authors) [es

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

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

    2005-10-01

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

  8. Multidetector row computed tomography may accurately estimate plaque vulnerability. Does MDCT accurately estimate plaque vulnerability? (Pro)

    International Nuclear Information System (INIS)

    Komatsu, Sei; Imai, Atsuko; Kodama, Kazuhisa

    2011-01-01

    Over the past decade, multidetector row computed tomography (MDCT) has become the most reliable and established of the noninvasive examination techniques for detecting coronary heart disease. Now MDCT is chasing intravascular ultrasound (IVUS) in terms of spatial resolution. Among the components of vulnerable plaque, MDCT may detect lipid-rich plaque, the lipid pool, and calcified spots using computed tomography number. Plaque components are detected by MDCT with high accuracy compared with IVUS and angioscopy when assessing vulnerable plaque. The TWINS study and TOGETHAR trial demonstrated that angioscopic loss of yellow color occurred independently of volumetric plaque change by statin therapy. These 2 studies showed that plaque stabilization and regression reflect independent processes mediated by different mechanisms and time course. Noncalcified plaque and/or low-density plaque was found to be the strongest predictor of cardiac events, regardless of lesion severity, and act as a potential marker of plaque vulnerability. MDCT may be an effective tool for early triage of patients with chest pain who have a normal electrocardiogram (ECG) and cardiac enzymes in the emergency department. MDCT has the potential ability to analyze coronary plaque quantitatively and qualitatively if some problems are resolved. MDCT may become an essential tool for detecting and preventing coronary artery disease in the future. (author)

  9. Complications of myocardial infarction on multidetector-row computed tomography of chest

    International Nuclear Information System (INIS)

    Raj, V.; Karunasaagarar, K.; Rudd, J.H.F.; Screaton, N.; Gopalan, D.

    2010-01-01

    Myocardial infarction (MI) secondary to coronary artery disease remains the leading cause of death in the western world. The advent of early reperfusion therapy has substantially decreased in-hospital mortality and has improved the outcome in survivors of the acute phase of MI. Complications of MI include ischaemic, mechanical, arrhythmic, embolic and inflammatory disturbances. Although some of these complications may be infrequent, their importance is underscored because of the potential ability to correct them with early diagnosis and appropriate treatment. The majority of these complications will be detected on clinical examination and confirmed by echocardiography. Some patients may undergo non-electrocardiogram (ECG)-gated thoracic multidetector-row computed tomography (MDCT) due to non-specific presentation. In this group, it is imperative for the radiologist to be aware of and be confident in diagnosing the complications secondary to MI. This review illustrates the spectrum and imaging features of acute and chronic complications of MI that can be visualized on both ECG-gated cardiac and non-ECG-gated thoracic MDCT.

  10. Complications of myocardial infarction on multidetector-row computed tomography of chest

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    Raj, V.; Karunasaagarar, K. [Department of Radiology, Papworth and Addenbrookes Hospital, Cambridge (United Kingdom); Rudd, J.H.F. [Division of Cardiovascular Medicine, University of Cambridge, Cambridge (United Kingdom); Screaton, N. [Department of Radiology, Papworth and Addenbrookes Hospital, Cambridge (United Kingdom); Gopalan, D., E-mail: deepa.gopalan@btopenworld.co [Department of Radiology, Papworth and Addenbrookes Hospital, Cambridge (United Kingdom)

    2010-11-15

    Myocardial infarction (MI) secondary to coronary artery disease remains the leading cause of death in the western world. The advent of early reperfusion therapy has substantially decreased in-hospital mortality and has improved the outcome in survivors of the acute phase of MI. Complications of MI include ischaemic, mechanical, arrhythmic, embolic and inflammatory disturbances. Although some of these complications may be infrequent, their importance is underscored because of the potential ability to correct them with early diagnosis and appropriate treatment. The majority of these complications will be detected on clinical examination and confirmed by echocardiography. Some patients may undergo non-electrocardiogram (ECG)-gated thoracic multidetector-row computed tomography (MDCT) due to non-specific presentation. In this group, it is imperative for the radiologist to be aware of and be confident in diagnosing the complications secondary to MI. This review illustrates the spectrum and imaging features of acute and chronic complications of MI that can be visualized on both ECG-gated cardiac and non-ECG-gated thoracic MDCT.

  11. Multidetector row computed tomography evaluation of the micropig kidney as a potential renal donor.

    Science.gov (United States)

    Yoon, Woong; Lee, Min Young; Ryu, Jung Min; Moon, Yong Ju; Lee, Sang Hun; Park, Jae Hong; Yun, Seung Pil; Jang, Min Woo; Park, Sung Su; Han, Ho Jae

    2010-03-01

    Multidetector row computed tomography (MDCT) provides anatomical information about the kidney and other internal organs. Presently, the suitability of 64-channel MDCT to assess the kidney of healthy micropigs was evaluated. Morphological evaluations of the kidney and the major renal vessels of six healthy micropigs were carried out using MDCT, recording kidney volume and the diameter and length of renal arteries and veins. The mean diameters and lengths of the renal artery were 0.44 +/- 0.05 and 4.51 +/- 0.55 cm on the right side and 0.46 +/- 0.06 and 3.36 +/- 0.27 cm on the left side, respectively. The mean diameters and lengths of the renal vein were 1.44 +/- 0.52 and 4.22 +/- 1.29 cm on the right side and 1.38 +/- 0.17 and 5.15 +/- 0.87 cm on the left side, respectively. The mean volume of the right kidney was 79.3 +/- 14.5 mL and of the left kidney was 78.0 +/- 13.9 mL. The data presented in this study suggest that the MDCT offers a noninvasive, rapid, and accurate method for the evaluation of the renal anatomy in living kidney donors. It also provides sufficient information about extra-renal anatomy important for donor surgery and determination of organ suitability.

  12. Enhanced multidetector-row computed tomography (MDCT) in the diagnosis of acute appendicitis and its severity

    International Nuclear Information System (INIS)

    Miki, Tesshou; Ogata, Seiji; Uto, Mitsunobu; Nakazono, Toshihiro; Urata, Miyuki; Ishibe, Ryouhei; Shinyama, Shin; Nakajo, Masayuki

    2005-01-01

    The purpose of this study was to examine the accuracy of enhanced multidetector-row computed tomography (MDCT) in diagnosing acute appendicitis and its severity. Contrast-enhanced MD-CT 3.5 mm thick images of 23 control patients (A), and 64 patients with surgically proven acute appendicitis including 8 catarrhal (B), 28 phiegmonous (C), and 28 gangrenous (D) appendicitis patients were respectively analyzed. The number of observed major computed tomography (CT) findings for each patient group were as follows: enlarged (≥6 mm in maximum diameter) appendix (A: 5, B: 8, C: 28, D: 28), enhancement of the appendiceal wall; hyper (A: 3, B: 8, C: 27, D: 20), iso (A: 15, B: 0, C: 1, D: 2), hypo (A-C: 0, D: 4), and patched (A-C: 0, D: 2) enhancement, appendicolith (A, B: 0, C: 7, D: 13), dirty fat sign (A: 3, B: 1, C: 21, D: 28), localized ascites (A: 2, B: 0, C: 2, D: 11), and abscess formation (A-C: 0, D: 5). From the combinations of these findings, we could differentiate acute appendicitis from the control normal appendix with an accuracy of 99% and could diagnose the severity of acute appendicitis with accuracies of 92% for catarrhal appendicitis, 84% for phlegmonous appendicitis, and 92% for gangrenous appendicitis. We could also visually reconstruct the entire forms and positions of the appendices from the successive CT findings because of the high-resolution thin-slice MDCT images. MDCT is highly accurate in the diagnosis of acute appendicitis and its severity. (author)

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  14. The value of multidetector-row computed tomography for localization of obscure acute gastrointestinal bleeding

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    Chang, Wei-Chou [Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Tsai, Shih-Hung [Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Chang, Wei-Kuo [Division of Gasteroenterology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Liu, Chang-Hsien [Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Tung, Ho-Jui [Department of Healthcare Administration, Asia University, Taichung, Taiwan (China); Hsieh, Chung-Bao [Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Huang, Guo-Shu; Hsu, Hsian-He [Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Yu, Chih-Yung, E-mail: chougo2002@yahoo.com.tw [Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China)

    2011-11-15

    Purpose: There are no simple guidelines on when to perform multidetector-row computed tomography (MDCT) for diagnosis of obscure acute gastrointestinal bleeding (AGIB). We used a risk scoring system to evaluate the diagnostic power of MDCT for patients with obscure AGIB. Materials and methods: Ninety-two patients with obscure AGIB who were referred for an MDCT scan after unsuccessful endoscopic treatment at presentation were studied. We recorded clinical data and calculated Blatchford score for each patient. Patients who required transfusion more than 500 mL of blood to maintain the vital signs were classified as high-risk patients. Two radiologists independently reviewed and categorized MDCT signs of obscure AGIB. Discordant findings were resolved by consensus. One-way ANOVA was used to compare clinical data between two groups; kappa statistics were used to estimate agreement on MDCT findings between radiologists. Results: Of the 92 patients, 62 (67.4%) were classified as high-risk patients. Blatchford scores of high-risk patients were significantly greater than those of low-risk patients. Sensitivity for MDCT diagnosing obscure AGIB was 81% in high-risk patients, as compared with 50% in the low-risk. When used in conjunction with selection of the cut-off value of 13 in Blatchford scoring system, the sensitivity and specificity of MDCT were 70.9% and 73.7%, respectively. Contrast extravasation was the most specific sign of AGIB (k = .87), recognition of which would have improved diagnostic accuracy. Conclusions: With the aid of Blatchford scoring system for evaluating the disease severity, MDCT can localize the bleeders of obscure AGIB more efficiently.

  15. Water as a contrast medium: a re-evaluation using the multidetector-row computed tomography.

    Science.gov (United States)

    Makarawo, Tafadzwa P; Negussie, Edsa; Malde, Sachit; Tilak, Jacqueline; Gayagoy, Jennifer; Watson, Jenna; Francis, Faiz; Lincoln, Denis; Jacobs, Michael J

    2013-07-01

    Water as an intraluminal negative contrast medium produces improved image quality with reduced artefact. However, rapid absorption of oral water in the bowel relative to speed and timing of image capturing has limited its clinical application. These findings predate advances in multidetector-row computed tomography (CT). To re-evaluate differences in image quality, we studied image clarity and luminal distention between the same group of patients who received both a pancreas protocol CT (PPCT) that uses oral water and a conventional positive oral contrast scan. We reviewed 66 patients who had previously undergone both a PPCT and an oral contrast abdominal CT. CT images were independently reviewed by two board-certified radiologists who scored degree of hollow viscus distention and visualization of mural detail using a Likert 5-point scale. Results were evaluated by using the Wilcoxon-signed rank test. Student's t test was applied to evaluate the differences in radiation dosage and Spearman's correlational test was used to evaluate interrater correlation between the radiologists. In comparing the mean radiation dosage, there was no statistical difference between the two protocols, and there was good interrater association with ratios of 0.595 and 0.51 achieved for the PPCT and conventional oral scan, respectively. The Wilcoxon signed-rank test showed statistical differences in the stomach (P contrast medium causing better or equal distention in the bowel and better or equal clarity than routine barium contrast. This calls for a need to reconsider the use of water as a contrast medium in clinical practice.

  16. The value of multidetector-row computed tomography for localization of obscure acute gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Chang, Wei-Chou; Tsai, Shih-Hung; Chang, Wei-Kuo; Liu, Chang-Hsien; Tung, Ho-Jui; Hsieh, Chung-Bao; Huang, Guo-Shu; Hsu, Hsian-He; Yu, Chih-Yung

    2011-01-01

    Purpose: There are no simple guidelines on when to perform multidetector-row computed tomography (MDCT) for diagnosis of obscure acute gastrointestinal bleeding (AGIB). We used a risk scoring system to evaluate the diagnostic power of MDCT for patients with obscure AGIB. Materials and methods: Ninety-two patients with obscure AGIB who were referred for an MDCT scan after unsuccessful endoscopic treatment at presentation were studied. We recorded clinical data and calculated Blatchford score for each patient. Patients who required transfusion more than 500 mL of blood to maintain the vital signs were classified as high-risk patients. Two radiologists independently reviewed and categorized MDCT signs of obscure AGIB. Discordant findings were resolved by consensus. One-way ANOVA was used to compare clinical data between two groups; kappa statistics were used to estimate agreement on MDCT findings between radiologists. Results: Of the 92 patients, 62 (67.4%) were classified as high-risk patients. Blatchford scores of high-risk patients were significantly greater than those of low-risk patients. Sensitivity for MDCT diagnosing obscure AGIB was 81% in high-risk patients, as compared with 50% in the low-risk. When used in conjunction with selection of the cut-off value of 13 in Blatchford scoring system, the sensitivity and specificity of MDCT were 70.9% and 73.7%, respectively. Contrast extravasation was the most specific sign of AGIB (k = .87), recognition of which would have improved diagnostic accuracy. Conclusions: With the aid of Blatchford scoring system for evaluating the disease severity, MDCT can localize the bleeders of obscure AGIB more efficiently.

  17. Intensive-care unit lung infections: The role of imaging with special emphasis on multi-detector row computed tomography

    International Nuclear Information System (INIS)

    Romano, Luigia; Pinto, Antonio; Merola, Stefanella; Gagliardi, Nicola; Tortora, Giovanni; Scaglione, Mariano

    2008-01-01

    Nosocomial pneumonia is the most frequent hospital-acquired infection. In mechanically ventilated patients admitted to an intensive-care unit as many as 7-41% may develop pneumonia. The role of imaging is to identify the presence, location and extent of pulmonary infection and the presence of complications. However, the poor resolution of bedside plain film frequently limits the value of radiography as an accurate diagnostic tool. To date, multi-detector row computed tomography with its excellent contrast resolution is the most sensitive modality for evaluating lung parenchyma infections

  18. Anatomical variation of thyroid veins on contrast-enhanced multi-detector row computed tomography

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    Tomita, Hayato, E-mail: m04149@yahoo.co.jp [Department of Radiology, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yasashicho, Asahi-ku, Yokohama, Kanagawa 241-0811 (Japan); Yamada, Takayuki; Murakami, Kenji; Hashimoto, Kazuki; Tazawa, Yoko; Kumano, Reiko [Department of Radiology, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yasashicho, Asahi-ku, Yokohama, Kanagawa 241-0811 (Japan); Nakajima, Yasuo [Department of Radiology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511 (Japan)

    2015-05-15

    Highlights: • This is the first study to demonstrate the anatomy of thyroid veins on contrasted-enhanced MDCT. • Identifying the thyroid vein on MDCT prior to selective venous sampling of parathyroid hormone provides clinical information to interventional radiologist. • Detecting especially the inferior thyroid veins with individual variability in numbers, locations, and lengths may have an effect on SVS for HPT and decrease the difficulty and time of the procedure. - Abstract: Objective: The objective of this study was to clarify the anatomical variation of thyroid veins into the systemic vein using contrast-enhanced multi-detector row computed tomography (MDCT). Design and methods: : The subjects were 80 patients (34 males and 46 females; mean age, 50.1 years; age range, 15–92 years) with neck diseases who underwent MDCT. The number and location of inflow points of the thyroid veins into the systemic vein, and the length from the junction of bilateral brachiocephalic veins to the orifice of inferior thyroid vein were investigated by reviewing the axial and coronal images. Results: All superior thyroid veins were detected. Right and left middle thyroid veins were identified in 39 and 29 patients, respectively. Right inferior thyroid veins, left inferior thyroid veins, and common trunks were detected in 43, 46, and 39 patients, respectively; in five patients, two left thyroid veins were identified. All left inferior thyroid veins and 34 common trunks flowed into the innominate vein, while right ones had some variations in inflow sites. Mean lengths were 3.01 ± 1.30 cm (range, 0.5–6.19) and 2.04 ± 0.91 cm (0.5–4.4) in the left inferior thyroid vein and common trunk, and 1.96 ± 1.05 cm (0.81–4.8) and 1.65 ± 0.69 cm (0.63–2.94) in the right one flowing into the right internal jugular vein and the innominate vein, respectively. Conclusions: The numbers and orifices of thyroid veins were identified at high rates on contrast-enhanced MDCT. This

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

    Science.gov (United States)

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

    2016-01-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  1. Defining Anatomic Variants of the Coronary Artery in Taiwanese Subjects Using 64-Multidetector-Row Computed Tomography

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    Hung-Jung Wang

    2007-10-01

    Full Text Available The newly developed 64-multidetector-row computed tomography (MDCT prompted us to evaluate coronary angiography using this noninvasive method. We reviewed 281 images of MDCT coronary angiography in Taiwanese. The origins of the coronary arteries were identified from the luminal aspect of the aorta. We described them as seen from the aortic sinus looking toward the cardiac ventricle. The sinus facing the left ventricle was designated sinus 1, and that facing the right ventricle was designated sinus 2. Anatomic variants of the coronary artery were divided into five types according to the structure of the left anterior descending artery, right coronary artery, and left circumflex artery. Of the 281 patients, 275 (97.9% had the type I variant in which the right coronary artery originated from sinus 2. MDCT provides advantages in defining anatomic variation and helps in the planning of clinical therapy or surgery.

  2. Multidetector-row computed tomography coronary angiography. Optimization of image reconstruction phase according to the heart rate

    International Nuclear Information System (INIS)

    Nagatani, Yukihiro; Takahashi, Masashi; Takazakura, Ryutaro; Nitta, Norihisa; Murata, Kiyoshi; Ushio, Noritoshi; Matsuo, Shinro; Yamamoto, Takashi; Horie, Minoru

    2007-01-01

    The purpose of this study was to optimize the image reconstruction phase of multidetector-row computed tomography (MDCT) coronary angiography according to the heart rate is crucial. Scan data were reconstructed for 10 different phases in 58 sequential patients who under went 8-row cardiac MDCT. The obtained images were scored and compared in terms of motion artifacts and visibility of the vessels, and moreover, electrocardiogram (ECG) record-based evaluations were added for clarification of the temporal relationships among these 10 phases. In the cases with lower heart rates ( 65 beats/mm), they were obtained in the late systolic period. As the heart rate increased, the optimal image reconstruction phase changed from mid diastole to late systole. However, it is recommended to try to decrease the heart rate of patients before data acquisition. (author)

  3. Prospective Electrocardiogram-Gated Multidetector Row Computed Tomography Coronary Angiography. Analysis of Quality Image and Radiation Dose

    International Nuclear Information System (INIS)

    Carrascosa, P.; Capunay, C.; Deviggiano, A.; Tajer, C.D.; Vallejos, J.; Goldsmit, A.; Garcia, M.J.

    2009-01-01

    Multidetector row computed tomography coronary angiography (MDCT-CA) has become a useful diagnostic tool for the direct quantification of coronary stenosis, for identifying coronary anomalies and for the assessment of coronary artery bypass grafts. Despite its clinical value has been questioned due to the effective radiation dose (ERD) received by each patient, radiation exposure is similar to other studies. However, different strategies are permanently tested in order to reduce the ERD maintaining adequate and diagnostic image quality. Objectives: To determine the image quality and effective radiation dose (ERD) of prospective electrocardiogram-gated multidetector row computed tomography coronary angiography (PMDCTCA) (the x-ray beam is turned on for only a short portion of diastole) compared to retrospective ECG gating (RMDCTCA) (the x-ray beam is turned on throughout the cardiac cycle) and a preliminary approach of its diagnostic accuracy compared to digital invasive coronary angiography (CA). Material and Methods: Fifty consecutive patients with suspected coronary artery disease and sinus rhythm were evaluated with PMDCT-CA and compared to a control group who underwent RMDCTCA. Image quality was analyzed by two reviewers. Interobserver concordance and ERD were determined. The diagnostic accuracy of PMDCT-CA compared to CA to detect coronary artery stenosis > 50% was assessed in 30 patients. Results: There were no significant differences in the image quality between both groups. Agreement between the reviewers for segment image quality scores was k = 0.92. Mean ERD was 3.5 mSv for PMDCT-CA compared to 9.7 and 12.9 mSv for RMDCT-CA with and without tube current modulation, respectively. Individual analysis including all segments showed that the sensitivity, specificity, positive predictive value and negative predictive value of PMDCT-CA for the detection of coronary stenosis were 94.74%, 81.82%, 90% and 90%, respectively. Conclusion: Our initial experience

  4. Multidetector row computed tomography noninvasively assesses coronary reperfusion after thrombolytic therapy in patients with ST elevation myocardial infarction

    International Nuclear Information System (INIS)

    Shin, Dong-Il; Won, Yoo-Dong; Chang, Kiyuk

    2006-01-01

    The study objective was to assess the efficacy of 16-slice multidetector row computed tomography (MDCT) in estimating residual stenosis and successful reperfusion after thrombolysis in patients with ST-elevation myocardial infarction (STEMI). A total of 31 patients with STEMI underwent MDCT scanning within 6 h (mean 4.6±1.1) after thrombolysis and the results for detection of significant residual stenosis and distal flow of the infarct-related artery were compared with those from conventional coronary angiography (CCAG) performed within 24 h (mean 12.1±5.6) after the MDCT scan. Successful reperfusion was defined as Thrombolysis In Myocardial Infarction flow 2 or 3 on CCAG and full contrast enhancement of the distal artery landmarks on MDCT. A final analysis was performed using 24 patients (312 segments). MDCT had a positive predictive value of 73.3% and a negative predictive value of 95.1% for detecting significant residual stenosis. It accurately estimated 17 of 18 patients (94.4%) with successful reperfusion and 5 of 6 (83.3%) with failed reperfusion on the basis of comparison with CCAG. MDCT demonstrated high accuracy not only for the detecting residual stenosis, but also for assessing successful reperfusion after thrombolytic therapy in patients with STEMI. (author)

  5. Imaging quality and effective radiation dose of prospective ECG-gated axial multidetector row computed tomography coronary angiography

    International Nuclear Information System (INIS)

    Capunay, C.; Carrascosa, P.; Vallejos, J.; Deviggiano, A.; Pollono, P.M.; Garcia, M.J.

    2011-01-01

    Objective. To determine the imaging quality and effective radiation dose (ERD) of prospective ECG-gated multidetector row computed tomography coronary angiography (PMDCTCA) compared to retrospective ECG-gating (RMDCT-CA). Materials and Methods. Forty-five PMDCT-CA scans were retrospectively reviewed for assessing imaging quality and ERD, and compared to 90 RMDCT-CA scans performed with (n=45) and without (n=45) tube current modulation, selected from our database on the basis of similar demographical characteristics. ERD was compared between all three groups. Imaging quality was assessed by two independent observers and compared to the imaging quality of the group of RMDCT-CA scans performed with tube current modulation. The interobserver variability was also determined. Results. There were no significant differences in imaging quality between the two groups. Interobserver variability was k=0.92 (95 % CI: 0.87-0.96). The ERD (mean ± SD) using PMDCT-CA was 2.88 ± 0.37 mSv compared to 10.50 ± 1.15 mSv (p [es

  6. Multidetector-row computed tomography of thoracic aortic anomalies in dogs and cats: Patent ductus arteriosus and vascular rings

    Directory of Open Access Journals (Sweden)

    Nolte Ingo

    2011-09-01

    Full Text Available Abstract Background Diagnosis of extracardiac intrathoracic vascular anomalies is of clinical importance, but remains challenging. Traditional imaging modalities, such as radiography, echocardiography, and angiography, are inherently limited by the difficulties of a 2-dimensional approach to a 3-dimensional object. We postulated that accurate characterization of malformations of the aorta would benefit from 3-dimensional assessment. Therefore, multidetector-row computed tomography (MDCT was chosen as a 3-dimensional, new, and noninvasive imaging technique. The purpose of this study was to evaluate patients with 2 common diseases of the intrathoracic aorta, either patent ductus arteriosus or vascular ring anomaly, by contrast-enhanced 64-row computed tomography. Results Electrocardiography (ECG-gated and thoracic nongated MDCT images were reviewed in identified cases of either a patent ductus arteriosus or vascular ring anomaly. Ductal size and morphology were determined in 6 dogs that underwent ECG-gated MDCT. Vascular ring anomalies were characterized in 7 dogs and 3 cats by ECG-gated MDCT or by a nongated thoracic standard protocol. Cardiac ECG-gated MDCT clearly displayed the morphology, length, and caliber of the patent ductus arteriosus in 6 affected dogs. Persistent right aortic arch was identified in 10 animals, 8 of which showed a coexisting aberrant left subclavian artery. A mild dilation of the proximal portion of the aberrant subclavian artery near its origin of the aorta was present in 4 dogs, and a diverticulum analogous to the human Kommerell's diverticulum was present in 2 cats. Conclusions Contrast-enhanced MDCT imaging of thoracic anomalies gives valuable information about the exact aortic arch configuration. Furthermore, MDCT was able to characterize the vascular branching patterns in dogs and cats with a persistent right aortic arch and the morphology and size of the patent ductus arteriosus in affected dogs. This additional

  7. Multidetector row computed tomography findings from ischemia to infarction of the large bowel

    International Nuclear Information System (INIS)

    Romano, Stefania; Romano, Luigia; Grassi, Roberto

    2007-01-01

    Objective: MDCT is performed as first imaging examination for patients with acute abdomen in most Emergency Departments. Clinical suspicion of ischemic colitis and infarction is related to specific findings, however, differential diagnosis as well as the staging for a confirmed ischemic affection may be critical. The individual signs from ischemia to infarction of large bowel is a captivating topic. In this study, we report our experience of the MDCT assessment of acute colonic disease from vascular mesenteric disorders. Materials and methods: We retrospectively reviewed the MDCT findings of 71 patients admitted to our attention for acute abdomen, with final proven diagnosis of colonic ischemia and/or infarction made by surgery and/or endoscopy. CT-scanning of the abdomen and pelvis was performed after i.v. contrast medium administration, using a multidetector row CT equipment. We correlated the presence of parietal disease, the evidence of mesenteric arterial or venous vessels occlusion, the parietal features as well as others findings, such as free fluid and/or air in peritoneal recess or in retroperitoneum, with the surgical and/or endoscopic findings. Results: Analysis of our data showed a segmental (84%) or complete (16%) involvement of the colon; 57 cases were related to ischemia, 14 to infarction. Inferior mesenteric vessels defect of opacification was noted in 10 cases. Various degree of wall thickening and parietal enhancement, peritoneal fluid, mural or portal-mesenteric pneumatosis were compared to evidence of mesenteric arterial or vein occlusion and to final proven diagnosis. A classification in a multi-stage grading for both decreased of arterial supply or impaired venous drainage disorders was done. Conclusions: A grading scale from ischemia to infarction affecting the large bowel from arterial or venous mesenteric vessels origin has been not previously reported in a series at our knowledge. MDCT findings may support the clinical evaluation of

  8. Multidetector-row helical computed tomography in the evaluation of cervical spine disorders; Tomografia computadorizada multislice no diagnostico das afeccoes da coluna cervical

    Energy Technology Data Exchange (ETDEWEB)

    Rosemberg, Laercio Alberto; Almeida, Milena Oliveira; Rios, Adriana Martins; Garbaccio, Viviane Ladeira; Kim, Nelson Ji Tae; Daniel, Mauro Miguel; Funari, Marcelo Buarque de Gusmao [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil). Dept. de Imagem]. E-mail: laercio@einstein.br

    2003-07-01

    Multidetector-row computed tomography (MRCT) has advantages in comparison to conventional helical computed tomography, such as reduction of study time, lower radiation doses, fewer metallic artifacts and high quality multiplanar reformatting and three dimensional reconstructions. We reviewed 150 cervical spine examinations and selected the most illustrative cases including congenital anomalies, degenerative lesions, spinal infections, neoplasms, traumatic injuries and postoperative abnormalities. The quality of multiplanar reformatting and volume reconstructions of the MRCT made the detection and evaluation of most of cases with complex anatomy easier and more precise. (author)

  9. Correct diagnosis of vascular encasement and longitudinal extension of hilar cholangiocarcinoma by four-channel multidetector-row computed tomography

    International Nuclear Information System (INIS)

    Okumoto, Tadayuki; Yamada, Takayuki; Sato, Akihiro

    2009-01-01

    Accurate diagnosis of local invasion of hilar cholangiocarcinomas is challenging due to their small size and the anatomic complexity of the hepatic hilar region. On the other hand, the correct diagnosis of local invasion is essential for assuring the possibility of curative surgery. The purpose of this study was to evaluate the feasibility of four-channel multidetector-row computed tomography (MDCT) in the assessment of vascular and bile duct involvement, by which we could obtain useful information for the surgical management of hilar cholangiocarcinoma. The subjects were 18 patients for whom the extent of tumor invasion was surgically and pathologically confirmed. All patients underwent preoperative multiphasic CT scanning by MDCT. Arterial and portal dominant phases were acquired using a detector configuration of 1.25 mm x 4 mm, and both axial and multiplanar reconstructed images were interpreted. Longitudinal extension was evaluated up to second-order branches. Vascular invasion is considered to be the degree of tumor contiguity to the hepatic arteries and portal vein and was graded by CT. The longitudinal extension was correctly diagnosed in 14 patients (77.8%). Hepatic artery invasion was correctly diagnosed in 17 patients with sensitivity of 100% and specificity of 90%, respectively. Portal vein invasion was correctly diagnosed in 47 of 51 branches with sensitivity and specificity of 92.3% and 90.2%, respectively. Multiplanar reconstructed images contributed to the correct diagnosis for both vascular encasement and longitudinal tumor extension. In conclusion, MDCT is useful in preoperative evaluation of hilar cholangiocarcinoma, especially when combined with multiplanar reconstructed images. (author)

  10. Assessment of temporal resolution of multi-detector row computed tomography in helical acquisition mode using the impulse method.

    Science.gov (United States)

    Ichikawa, Katsuhiro; Hara, Takanori; Urikura, Atsushi; Takata, Tadanori; Ohashi, Kazuya

    2015-06-01

    The purpose of this study was to propose a method for assessing the temporal resolution (TR) of multi-detector row computed tomography (CT) (MDCT) in the helical acquisition mode using temporal impulse signals generated by a metal ball passing through the acquisition plane. An 11-mm diameter metal ball was shot along the central axis at approximately 5 m/s during a helical acquisition, and the temporal sensitivity profile (TSP) was measured from the streak image intensities in the reconstructed helical CT images. To assess the validity, we compared the measured and theoretical TSPs for the 4-channel modes of two MDCT systems. A 64-channel MDCT system was used to compare TSPs and image quality of a motion phantom for the pitch factors P of 0.6, 0.8, 1.0 and 1.2 with a rotation time R of 0.5 s, and for two R/P combinations of 0.5/1.2 and 0.33/0.8. Moreover, the temporal transfer functions (TFs) were calculated from the obtained TSPs. The measured and theoretical TSPs showed perfect agreement. The TSP narrowed with an increase in the pitch factor. The image sharpness of the 0.33/0.8 combination was inferior to that of the 0.5/1.2 combination, despite their almost identical full width at tenth maximum values. The temporal TFs quantitatively confirmed these differences. The TSP results demonstrated that the TR in the helical acquisition mode significantly depended on the pitch factor as well as the rotation time, and the pitch factor and reconstruction algorithm affected the TSP shape. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  11. Influence of gating phase selection on the image quality of coronary arteries in multidetector row computed tomography

    International Nuclear Information System (INIS)

    Laskowska, K.; Marzec, M.; Serafin, Z.; Nawrocka, E.; Lasek, W.; WWisniewska-Szmyt, J.; Kubica, J.

    2005-01-01

    Motion artifacts caused by cardiac movement disturb the imaging of coronary arteries with multidetector-row spiral computed tomography. The aim of this study was to determine the phase of the heart rate which provides the best quality of coronary artery imaging in retrospective ECG-gated CT. Although 75% is usually the best reconstruction phase, the optimal phase should be established individually for the patient, artery, segment, and type of tomograph for the best imaging quality. Forty-five cardiac CT angiograms of 26 patients were retrospectively evaluated. The examinations were performed with a 4-detector-row tomograph. ECG-gated retrospective reconstructions were relatively delayed at 0%, 12.5%, 25%, 37.5%, 50%, 62.5%, 75%, and 87.5% of the cardiac cycle. Selected coronary arteries of the highest diagnostic quality were estimated in the eight phases of the cardiac cycle. Only arteries of very high image quality were selected for analysis: left coronary artery trunks (44 cases, incl. 37 stented), anterior interventricular branches (36, incl. 3 stented), circumflex branches (16), right coronary rtery branches (23), and posterior interventricular branches (4). The reconstruction phase had a statistically significant impact on the quality of imaging (p < 0.0003). Depending on the case, optimal imaging was noted in various phases, except in the 12.5 % phase. The 75% phase appeared to be the best of all those examined (p < 0.05), both in the group of arteries without stents (p < 0.0006) and in those stented (p < 0.05). In some cases of repeated examinations the best phases differed within the same patient. (author)

  12. Usefulness and safety of propranolol injection into vein for acquisition of coronary multidetector-row computed tomography

    International Nuclear Information System (INIS)

    Sekine, Takako; Kodama, Takahide; Kondo, Takeshi

    2010-01-01

    A low heart rate (HR), associated with a prolonged slow filling phase (SF), is necessary to obtain a high quality coronary CT at a low radiation dose with conventional 64 multidetector-row computed tomography (MDCT). The purpose of our study was to confirm the safety of injecting propranolol (2-10 mg) into the vein for lowering heart rate in patients requiring MDCT and to document the effect of the drug on HR, PQ and SF. Of 1290 consecutive patients who were initially considered for enrollment in the coronary MDCT study, 40 patients with atrial fibrillations, 3 with atrial flutters, and 13 with artificial pacemakers were excluded. Of the remaining 1234 patients (M/F=714/520), 331 had already taken an oral beta-blocker before the CT examination, and were included in the study. In patients with no contraindications, propranolol was aggressively injected (2-10 mg) into the vein to reduce the HR. In patients not taking an oral beta blocker, 2 mg propranolol reduced the HR by -10±5 bpm and 10 mg, by -20±7 bpm. However, in patients taking an oral beta-blocker, the decrease in HR by propranolol was minimal (2 mg, -6±4 bpm; 10 mg, -10±6 bpm). Propranolol significantly prolonged the PQ interval (from 169±27 to 179±29 ms, P<0.0001), and SF (from 125±69 to 264±79 ms, P<0.0001). Adverse effects of propranolol injection were observed in only 3 [2 mild hypotension and 1 paroxysmal atrial fibrillation (recovered to sinus rhythm by DC counter shock)] of 3212 patients. All 3 patients became stable after 1 or 2 hours of rest and could return home. Propranolol injection was a relatively safe and useful method to reduce HR and prolong SF, necessary for obtaining high quality coronary MDCT with a low radiation dose. (author)

  13. Multidetector-row computed tomography for evaluating the branching angle of the celiac artery: a descriptive study

    International Nuclear Information System (INIS)

    Tokue, Hiroyuki; Tokue, Azusa; Tsushima, Yoshito

    2012-01-01

    We performed this study in order to investigate the shape of the origin of the celiac artery in maximum intensity projection (MIP) using routine 64 multidetector-row computed tomography (MDCT) data in order to plan for the implantation of an intra-arterial hepatic port system. A total of 1,104 patients with hepatocellular carcinoma were assessed with MDCT. In the definition of the branching angle, the anterior side of the abdominal aorta was considered the baseline, and the cranial and caudal sides were designated as 0 and 180 degrees, respectively. The angles between 0 and 90 degrees and between 90 and 180 degrees from the cranial side were considered upward and downward, respectively, and the branching angle of the celiac artery was classified every 30 degrees. The subclavian arterial route was used for the implantation of an intra-arterial hepatic port system in patients with branching angles of 150 degrees or more (sharp downward). The median branching angle was (median ± standard deviation) 135 ± 23 (range, 51–174) degrees. The branching was upward in 77 patients (7%) and downward in 1,027 patients (93%). The branching was downward with an angle of 120 to150 degrees in most patients (n = 613). The branching was sharply downward with an angle of 150 degrees or more in 177 patients (16%). A total of 10 patients were referred for interventional placement of an intra-arterial hepatic port system. The subclavian arterial route was used for implantation of an intra-arterial hepatic port system in 2 patients with sharp downward branching. The branching angle of the celiac artery can be easily determined by the preparation of MIP images from routine MDCT data. MIP may provide useful information for the selection of the catheter insertion route in order to avoid a sharp branching angle of the celiac artery

  14. Accuracy of multidetector row computed tomography for the diagnosis of acute bowel ischemia in a non-selected study population

    International Nuclear Information System (INIS)

    Wiesner, Walter; Hauser, Andreas; Steinbrich, Wolfgang

    2004-01-01

    The diagnostic accuracy of multidetector row computed tomography for the prospective diagnosis of acute bowel ischemia in the daily clinical routine was analyzed. Two hundred ninety-one consecutive patients with an acute or subacute abdomen, examined by MDCT over a time period of 5 months, were included in the study. All original CT diagnoses made during the daily routine by radiological generalists were compared to the final diagnoses made by using all available medical information from endoscopies, surgical interventions, autopsies and follow-up. Finally, all CT examinations of patients with an initial CT diagnosis or a final diagnosis of bowel ischemia were reread by a radiologist specialized in abdominal imaging in order to analyze the CT findings and the reasons for initially false negative or false positive CT readings. Twenty-four patients out of 291 (8.2%) had acute bowel ischemia. The age of affected patients ranged from 50 to 94 years (mean age: 75.7 years). Eleven patients were male, and 13 female. Reasons for acute bowel ischemia were: arterio-occlusive (n=11), non-occlusive (n=5), strangulation (n=2), over-distension (n=3) and radiation (n=3). The prospective sensitivity, specificity, PPV and NPV of MDCT for the diagnosis of acute bowel ischemia in the daily routine were 79.17, 98.51, 90.48 and 98.15%. MDCT reaches a similarly high sensitivity in diagnosing acute bowel as angiography. Furthermore, it has the advantage of being helpful in most of its clinical differential diagnoses and of being less invasive with the consecutive possibility of being used earlier in the diagnostic process with all the resulting positive effects on the patients prognosis. Therefore, nowadays MDCT should probably be used as the first step imaging modality of choice in patients with suspected acute bowel ischemia. (orig.)

  15. Multidetector-row computed tomography for evaluating the branching angle of the celiac artery: a descriptive study

    Directory of Open Access Journals (Sweden)

    Tokue Hiroyuki

    2012-12-01

    Full Text Available Abstract Background We performed this study in order to investigate the shape of the origin of the celiac artery in maximum intensity projection (MIP using routine 64 multidetector-row computed tomography (MDCT data in order to plan for the implantation of an intra-arterial hepatic port system. Methods A total of 1,104 patients with hepatocellular carcinoma were assessed with MDCT. In the definition of the branching angle, the anterior side of the abdominal aorta was considered the baseline, and the cranial and caudal sides were designated as 0 and 180 degrees, respectively. The angles between 0 and 90 degrees and between 90 and 180 degrees from the cranial side were considered upward and downward, respectively, and the branching angle of the celiac artery was classified every 30 degrees. The subclavian arterial route was used for the implantation of an intra-arterial hepatic port system in patients with branching angles of 150 degrees or more (sharp downward. Results The median branching angle was (median ± standard deviation 135 ± 23 (range, 51–174 degrees. The branching was upward in 77 patients (7% and downward in 1,027 patients (93%. The branching was downward with an angle of 120 to150 degrees in most patients (n = 613. The branching was sharply downward with an angle of 150 degrees or more in 177 patients (16%. A total of 10 patients were referred for interventional placement of an intra-arterial hepatic port system. The subclavian arterial route was used for implantation of an intra-arterial hepatic port system in 2 patients with sharp downward branching. Conclusions The branching angle of the celiac artery can be easily determined by the preparation of MIP images from routine MDCT data. MIP may provide useful information for the selection of the catheter insertion route in order to avoid a sharp branching angle of the celiac artery.

  16. Renal replacement lipomatosis: multidetector-row computed tomography findings in one case

    International Nuclear Information System (INIS)

    Calisir, C.; Can, C.; Kebapci, M.

    2007-01-01

    Replacement lipomatosis of the kidney is the result of severe atrophy of the renal parenchyma often caused by chronic calculus disease with secondary marked benign proliferation of fibrofatty tissue replacing atrophied renal parenchyma. Different radiological modalities have been used to illustrate this entity, with magnetic resonance imaging, ultrasound, intravenous pyelogram, and computed tomography (CT) used most frequently. We report multidedector CT (MDCT) findings of replacement lipomatosis in a 50-year-old woman. We think that it accurately provides a complete one-step diagnostic workup and appropriate pre-surgical planning for patients for whom there is a suspicion of replacement lipomatosis

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-02-15

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

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

  19. Noninvasive imaging of coronary arteries: current and future role of multidetector row computer tomography

    International Nuclear Information System (INIS)

    Nedevska, M.; Stoinova, V.

    2006-01-01

    Full text: This review will present the current and future role of cardiac computer tomography (CCT), and particular multidetector CCT, for imaging of atherosclerotic pathologic changes of the coronary arteries. Atherosclerosis and its cardio-vascular complications represent one of the major issues of public health in industrial countries. Different imaging modalities, including invasive coronarography, have been aimed to the diagnosis of the disease, when it provokes symptomatic decrease of the blood flow. In spite of development of surgical and percutaneous methods for coronary revascularization, coronary artery disease remains the major cause of death in North America and Europe. This demonstrates the need of novel, complementary diagnostic strategies, aimed to identify asymptomatic stages as the basis of pharmacological interventions. Noninvasive coronary angiography with multidetector CT allows both assessment of luminal stenosis and subclinical disease of arterial wall. Large trails are missing now to understand and present what will be the role of this technology in the comprehensive assessment of patients, suspected of having CAD. Based on experience and current potentials we will describe how tomographic coronary imaging may eventually supplement traditional angiographic techniques in understanding the patterns of atherosclerotic CAD development

  20. Multidetector row computed tomography and ultrasound characteristics of caudal vena cava duplication in dogs.

    Science.gov (United States)

    Bertolini, Giovanna; Diana, Alessia; Cipone, Mario; Drigo, Michele; Caldin, Marco

    2014-01-01

    Caudal vena cava duplication has been rarely reported in small animals. The purpose of this retrospective study was to describe characteristics of duplicated caudal vena cava in a large group of dogs. Computed tomography (CT) and ultrasound databases from two hospitals were searched for canine reports having the diagnosis "double caudal vena cava." One observer reviewed CT images for 71 dogs and two observers reviewed ultrasound images for 21 dogs. In all CT cases, the duplication comprised two vessels that were bilaterally symmetrical and approximately the same calibre (similar to Type I complete duplication in humans). In all ultrasound cases, the duplicated caudal vena cava appeared as a distinct vessel running on the left side of the abdominal segment of the descending aorta and extending from the left common iliac vein to the left renal vein. The prevalence of caudal vena cava duplication was 0.46% for canine ultrasound studies and 2.08% for canine CT studies performed at these hospitals. Median body weight for affected dogs was significantly lower than that of unaffected dogs (P dogs, caudal vena cava duplication should be differentiated from other vascular anomalies when planning surgeries and for avoiding misdiagnoses. © 2014 American College of Veterinary Radiology.

  1. Limitations of airway dimension measurement on images obtained using multi-detector row computed tomography.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Oguma

    Full Text Available OBJECTIVES: (a To assess the effects of computed tomography (CT scanners, scanning conditions, airway size, and phantom composition on airway dimension measurement and (b to investigate the limitations of accurate quantitative assessment of small airways using CT images. METHODS: An airway phantom, which was constructed using various types of material and with various tube sizes, was scanned using four CT scanner types under different conditions to calculate airway dimensions, luminal area (Ai, and the wall area percentage (WA%. To investigate the limitations of accurate airway dimension measurement, we then developed a second airway phantom with a thinner tube wall, and compared the clinical CT images of healthy subjects with the phantom images scanned using the same CT scanner. The study using clinical CT images was approved by the local ethics committee, and written informed consent was obtained from all subjects. Data were statistically analyzed using one-way ANOVA. RESULTS: Errors noted in airway dimension measurement were greater in the tube of small inner radius made of material with a high CT density and on images reconstructed by body algorithm (p<0.001, and there was some variation in error among CT scanners under different fields of view. Airway wall thickness had the maximum effect on the accuracy of measurements with all CT scanners under all scanning conditions, and the magnitude of errors for WA% and Ai varied depending on wall thickness when airways of <1.0-mm wall thickness were measured. CONCLUSIONS: The parameters of airway dimensions measured were affected by airway size, reconstruction algorithm, composition of the airway phantom, and CT scanner types. In dimension measurement of small airways with wall thickness of <1.0 mm, the accuracy of measurement according to quantitative CT parameters can decrease as the walls become thinner.

  2. Comparison of the multidetector-row computed tomography findings of IgG4-related sclerosing cholangitis and extrahepatic cholangiocarcinoma

    International Nuclear Information System (INIS)

    Yata, M.; Suzuki, K.; Furuhashi, N.; Kawakami, K.; Kawai, Y.; Naganawa, S.

    2016-01-01

    Aim: To compare the multidetector-row computed tomography (MDCT) findings of IgG4-related sclerosing cholangitis (IgG4-SC) and extrahepatic cholangiocarcinoma (EH-CCA). Materials and methods: Two radiologists who had no knowledge of the patients' clinical information retrospectively evaluated the CT findings of patients with IgG4-SC (n=33) and EH-CCA (n=39) on a consensus basis. Another radiologist measured the biliary lesions. IgG4-SC was diagnosed using the Japan Biliary Association criteria (2012) or the Mayo Clinic's HISORt criteria. EH-CCA was diagnosed based on surgical findings. Results: Compared with EH-CCA, IgG4-SC exhibited the following findings significantly more frequently: (a) wall thickening alone, (b) concentric wall thickening, (c) smooth inner margins, (d) homogeneous attenuation in the arterial phase, (e) a lesion involving the intrapancreatic bile duct, (f) smooth outer margins, (g) fully visible lumen, (h) a funnel-shaped proximal bile duct, (i) skip lesions, and (j) abnormal pancreatic findings. Conversely, (k) dual-layered attenuation in all phases was significantly more common in EH-CCA. The specificity values of parameters (e–k) were >80%. Regarding dimensions, (l) the biliary lesions were longer in IgG4-SC than in EH-CCA. (m) The diameters of the dilated proximal common bile duct and (n) the dilated proximal intrahepatic bile duct were smaller in IgG4-SC than in EH-CCA. Conclusion: A number of CT findings are useful for differentiating between IgG4-SC and EH-CCA. CT findings (e–k) are particularly useful for this purpose. - Highlights: • Some CT findings are useful for differentiating between IgG4-SC and EH-CCA. • Homogeneous attenuation in all phases was more common in IgG4-SC than in EH-CCA. • Abnormal pancreatic findings showed high sensitivity and specificity values. • Dual-layered attenuation in all phases was more common in EH-CCA than in IgG4-SC.

  3. Congenital coronary artery anomalies: diagnosis with 64 slice multidetector row computed tomography coronary angiography: A single Centre Study

    International Nuclear Information System (INIS)

    Srnivasan, K.G.; Gaikward, A.; Kannan, B.R.J.; Ritesh, K.; Ushanandini, K.P.

    2008-01-01

    Full text: Retrospective review of the congenital coronary artery (CA) anomalies detected by a 64-slice multidetector row computed tomographic (MDCT) angiography. The type of the anomaly, imaging characteristics, clinical relevance and the superiority of the MDCT over conventional coronary angiography are discussed. Multidetector row computed tomographic coronary angiography was carried out by the usual technique with 70 cc of non-ionic contrast agent and retrospective electrocardiogram gating. The volume data obtained were reconstructed in axial plane, along with volume-rendered three-dimensional reconstruction and virtual angioscopy in selected patients. The images were analysed by a radiologist, experienced in cardiac CT, and an experienced cardiologist. A retrospective review of the records was carried out, and subjects with congenital coronary anomalies were included in the study. Between 15 November 2005 and 27 February 2007, 1495 MDCT coronary angiograms were carried out. Eleven of them were found to have coronary anomalies. Five had absent left main CA. Two had interarterial course of the left main CA artery passing in between the right ventricular outflow tract and the root of aorta. In one patient, there was aberrant origin of right CA from the left aortic sinus with subsequent interarterial course and another one had aberrant origin of circumflex artery from the right aortic sinus. One patient each of congenitally absent circumflex artery and atresia of the right CA were found. Sixty-four slice MDCT coronary angiography provided accurate depiction of anomalous vessel origin and course along with the complex anatomical relation with the adjacent structures. CTcan be considered as a first-line imaging method for delineating coronary arterial anomalies.

  4. Evaluation of left ventricular function and volume with multidetector-row computed tomography. Comparison with electrocardiogram-gated single photon emission computed tomography

    International Nuclear Information System (INIS)

    Suzuki, Takeya; Yamashina, Shohei; Nanjou, Shuji; Yamazaki, Junichi

    2007-01-01

    This study compared left ventricular systolic function and volume determined by multidetector-row computed tomography (MDCT) and electrocardiogram-gated single photon emission computed tomography (G-SPECT) Thirty-seven patients with coronary artery disease and non-cardiovascular disease underwent MDCT. In this study, left ventricular ejection fraction (EF), left ventricular end-diastolic volume (EDV) and left ventricular end-systolic volume (ESV) were calculated using only two-phase imaging with MDCT. Left ventricular function and volume were compared using measurements from G-SPECT. We conducted MDCT and G-SPECT virtually simultaneously. Both the EF and ESV evaluated by MDCT closely correlated with G-SPECT (r=0.763, P 65 bpm) during MDCT significantly influenced the difference in EF calculated from MDCT and G-SPECT (P<0.05). Left ventricular function can be measured with MDCT as well as G-SPECT. However, a heart rate over 65 bpm during MDCT negatively affects the EF correlation between MDCT and G-SPECT. (author)

  5. Focal Stenosis in Right Upper Lobe Bronchus in a Recurrently Wheezing Child Sequentially Studied by Multidetector-row Spiral Computed Tomography and Scintigraphy

    Directory of Open Access Journals (Sweden)

    I-Chen Chen

    2009-12-01

    Full Text Available Lower respiratory tract infections associated with wheezing are not uncommon in infants and young children. Among the wheezing-associated disorders, allergic etiologies are more commonly encountered than anatomic anomalies. We present a 3-year-old girl with a sudden attack of asthmatic symptoms including dyspnea, cyanosis and diffuse wheezing. Based on a history of choking, and atelectasis in the right upper lobe detected by chest films, flexible tracheobronchoscopy was arranged and incidentally detected a stenotic orifice in the right upper lobe bronchus. Multidetector-row spiral computed tomography and pulmonary scintigraphy subsequently also disclosed the focal stenosis. She suffered from recurrent wheezing, pneumonia and lung atelectasis during 1 year of follow-up. We emphasize the diagnosis, clinical course and management of focal stenosis in the right upper lobe bronchus.

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

    International Nuclear Information System (INIS)

    Sekiya, Keiko; Mori, Shintaro; Sekiya, Kotaro

    2008-01-01

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

  7. Contrast enhancement in multidetector-row computed tomography (MDCT) of the abdomen: intraindividual comparison of contrast media containing 300 mg versus 370 mg iodine per ml

    International Nuclear Information System (INIS)

    Behrendt, F.F.; Mahnken, A.H.; Keil, S.; Das, M.; Hohl, C.; Guenther, R.W.; Muehlenbruch, G.; Bauer, D.; Seidensticker, P.; Jost, E.; Wildberger, J.E.

    2008-01-01

    The purpose of this study was to intraindividually evaluate the difference in intraluminal vessel and parenchyma contrast enhancement of two different iodine concentrations in multidetector-row computed tomography (MDCT) of the abdomen. Eighty-three patients underwent baseline and follow-up MDCT-scanning (Somatom Sensation 16; Siemens, Forchheim, Germany) of the abdomen using contrast media containing 370 mg iodine/ml (protocol A; Ultravist 370, Bayer Schering Pharma, Berlin, Germany) and 300 mg iodine/ml (protocol B; Ultravist 300). The total iodine load (37 g iodine) and the iodine delivery rate (1.29 g iodine/s) were identical for both protocols. Contrast enhancement in the portal venous phase was measured in the abdominal aorta, inferior vena cava, portal vein, liver, spleen, pancreas and kidney. Mean attenuation values were compared using paired t-test. Intraindividual comparison revealed no statistically significant differences of the mean attenuation values between protocols A and B for all anatomic sites: abdominal aorta, inferior vena cava, portal vein, liver, spleen, pancreas and kidney (all P > 0.05). Given an injection protocol with constant total iodine load and constant iodine delivery rate, the iodine concentration of contrast media does not significantly influence abdominal contrast enhancement in the portal venous phase. (orig.)

  8. Sixteen multidetector row computed tomography of pulmonary veins: 3-months' follow-up after treatment of paroxysmal atrial fibrillation with cryothermal ablation

    International Nuclear Information System (INIS)

    Maksimovic, Ruzica; Cademartiri, Filippo; Pattynama, Peter M.T.; Scholten, Marcoen F.; Jordaens, Luc J.

    2005-01-01

    The aim of the study was to assess pulmonary veins (PVs) for the presence of stenosis 3 months after cryothermal ablation (CA) with a new method of electrical isolation of PVs using contrast-enhanced 16 multidetector row computed tomography (MDCT). Twenty four patients with symptomatic atrial fibrillation underwent CA in 46 PVs. MDCT of PVs was performed before the treatment and after 3-months' follow-up. Following cryoablation, 13/24 (54%) patients showed clinical improvement and had reduced attacks of atrial fibrillation. The dimensions of the treated PVs remained unchanged: the coronal ostial diameter was 19.1±2.4 preprocedural versus 18.6±2.4 mm at follow-up, p>0.05; the ratio of the coronal and axial diameters at the ostium was 1.2±0.2 versus 1.2±0.1, p>0.05, respectively, and the coronal diameter of the proximal 10 mm was 17.1±2.5 mm versus 16.5±2.2 mm, p>0.05, respectively. CA is a promising technique for electrical isolation of PVs that has not been associated with stenosis at the orifice and the proximal 10 mm of the PVs after 3-months' follow-up. MDCT is a noninvasive, fast and comfortable method for assessment of PVs in a three-dimensional manner prior to ablative treatment and during the follow-up. (orig.)

  9. Sixteen multidetector row computed tomography of pulmonary veins: 3-months' follow-up after treatment of paroxysmal atrial fibrillation with cryothermal ablation

    Energy Technology Data Exchange (ETDEWEB)

    Maksimovic, Ruzica; Cademartiri, Filippo; Pattynama, Peter M.T. [Erasmus Medical Center, Department of Radiology, Rotterdam (Netherlands); Scholten, Marcoen F.; Jordaens, Luc J. [Erasmus Medical Center, Department of Cardiology, Rotterdam (Netherlands)

    2005-06-01

    The aim of the study was to assess pulmonary veins (PVs) for the presence of stenosis 3 months after cryothermal ablation (CA) with a new method of electrical isolation of PVs using contrast-enhanced 16 multidetector row computed tomography (MDCT). Twenty four patients with symptomatic atrial fibrillation underwent CA in 46 PVs. MDCT of PVs was performed before the treatment and after 3-months' follow-up. Following cryoablation, 13/24 (54%) patients showed clinical improvement and had reduced attacks of atrial fibrillation. The dimensions of the treated PVs remained unchanged: the coronal ostial diameter was 19.1{+-}2.4 preprocedural versus 18.6{+-}2.4 mm at follow-up, p>0.05; the ratio of the coronal and axial diameters at the ostium was 1.2{+-}0.2 versus 1.2{+-}0.1, p>0.05, respectively, and the coronal diameter of the proximal 10 mm was 17.1{+-}2.5 mm versus 16.5{+-}2.2 mm, p>0.05, respectively. CA is a promising technique for electrical isolation of PVs that has not been associated with stenosis at the orifice and the proximal 10 mm of the PVs after 3-months' follow-up. MDCT is a noninvasive, fast and comfortable method for assessment of PVs in a three-dimensional manner prior to ablative treatment and during the follow-up. (orig.)

  10. Efficacy of double arterial phase dynamic magnetic resonance imaging with the sensitivity encoding technique versus dynamic multidetector-row helical computed tomography for detecting hypervascular hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Kumano, Seishi; Okada, Masahiro; Murakami, Takamichi; Uemura, Masahiko; Haraikawa, Toyoaki; Hirata, Masaaki; Kikuchi, Keiichi; Mochizuki, Teruhito; Kim, Tonsok

    2009-01-01

    The aim of this study was to evaluate the efficacy of double arterial phase dynamic magnetic resonance imaging (MRI) with the sensitivity encoding technique (SENSE dynamic MRI) for detection of hypervascular hepatocellular carcinoma (HCC) in comparison with double arterial phase dynamic multidetector-row helical computed tomography (dynamic MDCT). A total of 28 patients with 66 hypervascular HCCs underwent both double arterial SENSE dynamic MRI and dynamic MDCT. The diagnosis of HCC was based on surgical resection (n=7), biopsy (n=10), or a combination of CT during arterial portography (CTAP), CT during hepatic arteriography (CTA), and/or the 6-month follow-up CT (n=49). Based on alternative-free response receiving operating characteristic (ROC) analysis, the diagnostic performance for detecting HCC was compared between double arterial phase SENSE dynamic MRI and double arterial phase dynamic MDCT. The mean sensitivity, positive predictive value, and mean A Z values for hypervascular HCCs were 72%, 80%, and 0.79, respectively, for SENSE dynamic MRI and 66%, 92%, and 0.78, respectively, for dynamic MDCT. The mean sensitivity for double arterial phase SENSE dynamic MRI was higher than that for double arterial phase dynamic MDCT, but the difference was not statistically significant. Double arterial phase SENSE dynamic MRI is as valuable as double arterial phase dynamic MDCT for detecting hypervascular HCCs. (author)

  11. Multidetector-row computed tomography for prosthetic heart valve dysfunction: is concomitant non-invasive coronary angiography possible before redo-surgery?

    Energy Technology Data Exchange (ETDEWEB)

    Tanis, Wilco [Haga Teaching Hospital, Department of Cardiology, The Hague (Netherlands); Haga Teaching Hospital, The Hague (Netherlands); Sucha, Dominika; Habets, Jesse [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Laufer, Ward; Chamuleau, Steven [University Medical Center Utrecht, Department of Cardiology, Utrecht (Netherlands); Herwerden, Lex.A. van [University Medical Center Utrecht, Department of Cardiothoracic Surgery, Utrecht (Netherlands); Symersky, Petr [Vrije Universiteit, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Budde, Ricardo P.J. [Erasmus Medical Center, Department of Radiology, Rotterdam (Netherlands)

    2015-06-01

    Retrospective ECG-gated multidetector-row computed tomography (MDCT) is increasingly used for the assessment of prosthetic heart valve (PHV) dysfunction, but is also hampered by PHV-related artefacts/cardiac arrhythmias. Furthermore, it is performed without nitroglycerine or heart rate correction. The purpose was to determine whether MDCT performed before potential redo-PHV surgery is feasible for concomitant coronary artery stenosis assessment and can replace invasive coronary angiography (CAG). PHV patients with CAG and MDCT were identified. Based on medical history, two groups were created: (I) patients with no known coronary artery disease (CAD), (II) patients with known CAD. All images were scored for the presence of significant (>50 %) stenosis. CAG was the reference test. Fifty-one patients were included. In group I (n = 38), MDCT accurately ruled out significant stenosis in 19/38 (50 %) patients, but could not replace CAG in the remaining 19/38 (50 %) patients due to non-diagnostic image quality (n = 16) or significant stenosis (n = 3) detection. In group II (n = 13), MDCT correctly found no patients without significant stenosis, requiring CAG imaging in all. MDCT assessed patency in 16/19 (84 %) grafts and detected a hostile anatomy in two. MDCT performed for PHV dysfunction assessment can replace CAG (100 % accurate) in approximately half of patients without previously known CAD. (orig.)

  12. Assessment of left ventricular myocardial function using 16-slice multidetector-row computed tomography: comparison with magnetic resonance imaging and echocardiography

    International Nuclear Information System (INIS)

    Heuschmid, Martin; Rothfuss, Julia K.; Fenchel, Michael; Stauder, Norbert; Kuettner, Axel; Miller, Stephan; Claussen, Claus D.; Kopp, Andreas F.; Schroeder, Stephen; Burgstahler, Christof; Franow, Andreas; Kuzo, Ronald S.

    2006-01-01

    To assess functional parameters using multidetector-row computed tomography (MDCT) and echocardiography and to compare the results with magnetic resonance imaging (MRI). End-diastolic-volume (EDV), end-systolic-volume (ESV), stroke-volume (SV), ejection-fraction (EF), and myocardial mass (MM) were calculated based on CT data sets from 52 patients. Echocardiography was performed in 24 of the 52 patients. The results from MDCT and echocardiography were compared with MRI. A strong correlation between MDCT and MRI (r=0.66-0.90) was found for all parameters. Echocardiography revealed a low or moderate correlation (0.05-0.59). Compared to MRI the average differences with MDCT were for EDV 15.1 ml, ESV 10.6 ml, SV 4.5 ml, EF 1.8%, and MM 8.2 g, for EDV determined by echocardiography 36.2 ml, ESV 6.8 ml, and EF 13.9%. Bland-Altman analysis revealed acceptable limits of agreement between MRI and MDCT. MDCT enables reliable quantification of left ventricular function. Echocardiography was found to have only a moderate agreement of functional parameters with MRI. (orig.)

  13. Evaluation of prosthetic valve obstruction on electrocardiographically gated multidetector-row computed tomography--identification of subprosthetic pannus in the aortic position.

    Science.gov (United States)

    Ueda, Tomohiro; Teshima, Hideki; Fukunaga, Shuji; Aoyagi, Shigeaki; Tanaka, Hiroyuki

    2013-01-01

    This study was performed to evaluate the diagnostic role of electrocardiographically gated multidetector-row computed tomography (MDCT) for prosthetic valve obstruction (PVO) in the aortic position. Between 2002 and 2006, 9 patients were diagnosed with PVO of an aortic bileaflet mechanical valve based on echocardiographic and cineradiographic criteria. These 9 patients were examined using MDCT before replacement of the mechanical valve, and intraoperative findings were compared to morphologic periprosthetic abnormalities observed on MDCT. CT attenuation (Hounsfield units; HU) of the periprosthetic abnormalities was measured to investigate the underlying cause of the PVO. MDCT showed subprosthetic masses extending beyond the prosthetic ring into the orifice of the valve. At reoperation, presence of subprosthetic pannus was confirmed in all of the 9 patients, but no periprosthetic thrombus was found. The mean CT attenuation of the subprosthetic pannus was 170 HU, and it was significantly greater than that obtained from the interventricular septum (108 HU; Ppannus causing PVO and the mean CT attenuation of subprosthetic pannus is significantly higher than that of the interventricular septum on MDCT.

  14. Multidetector-row computed tomography for prosthetic heart valve dysfunction: is concomitant non-invasive coronary angiography possible before redo-surgery?

    International Nuclear Information System (INIS)

    Tanis, Wilco; Sucha, Dominika; Habets, Jesse; Laufer, Ward; Chamuleau, Steven; Herwerden, Lex.A. van; Symersky, Petr; Budde, Ricardo P.J.

    2015-01-01

    Retrospective ECG-gated multidetector-row computed tomography (MDCT) is increasingly used for the assessment of prosthetic heart valve (PHV) dysfunction, but is also hampered by PHV-related artefacts/cardiac arrhythmias. Furthermore, it is performed without nitroglycerine or heart rate correction. The purpose was to determine whether MDCT performed before potential redo-PHV surgery is feasible for concomitant coronary artery stenosis assessment and can replace invasive coronary angiography (CAG). PHV patients with CAG and MDCT were identified. Based on medical history, two groups were created: (I) patients with no known coronary artery disease (CAD), (II) patients with known CAD. All images were scored for the presence of significant (>50 %) stenosis. CAG was the reference test. Fifty-one patients were included. In group I (n = 38), MDCT accurately ruled out significant stenosis in 19/38 (50 %) patients, but could not replace CAG in the remaining 19/38 (50 %) patients due to non-diagnostic image quality (n = 16) or significant stenosis (n = 3) detection. In group II (n = 13), MDCT correctly found no patients without significant stenosis, requiring CAG imaging in all. MDCT assessed patency in 16/19 (84 %) grafts and detected a hostile anatomy in two. MDCT performed for PHV dysfunction assessment can replace CAG (100 % accurate) in approximately half of patients without previously known CAD. (orig.)

  15. Quantitative assessment of lung volumes using multi-detector row computed tomography (MDCT) in patients with chronic obstructive pulmonary disease (COPD)

    International Nuclear Information System (INIS)

    Lee, Sang Min; Hur, Jin; Kim, Tae Hoon; Kim, Sang Jin; Kim, Hyung Jung

    2008-01-01

    To evaluate the clinical value of the multi-detector row computed tomography (MDCT) in the quantitative assessment of lung volumes and to assess the relationship between the MDCT results and disease severity as determined by a pulmonary function test (PFT) in Chronic Obstructive Pulmonary Disease (COPD) patients. We performed a PFT and MDCT on 39 COPD patients. Using the GOLD classifications, we divided the patients into three groups according to disease severity; stage I (mild, n = 10), stage II (moderate, n = 15), and stage III (severe, n = 14). Using the pulmo-CT software program, we measured the proportion of lung volumes with attenuation values below -910 and -950 HU. The mean FEV1 (% of predicted) and FEV1/FVC was 82.2 ± 2% and 66.2 ± 3% in stage I, 53.5 ± 11% and 52 ± 6% in stage II, and 32.3 ± 7% and 44.2% ± 13% in stage III, respectively. Differences in lung volume percentage at each of the thresholds (-910 and -950 HU) among the 3 stages were statistically significant (ρ < 0.01, ρ < 0.01) and correlated well with the FEV1 and FEV1/FVC (r = -0.803, r -0.766, r = -0.817, and r = -0.795, respectively). The volumetric measurement obtained by MDCT provides an accurate means of quantifying pulmonary emphysema

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  18. Influence of the Quantity of Aortic Valve Calcium on the Agreement Between Automated 3-Dimensional Transesophageal Echocardiography and Multidetector Row Computed Tomography for Aortic Annulus Sizing.

    Science.gov (United States)

    Podlesnikar, Tomaz; Prihadi, Edgard A; van Rosendael, Philippe J; Vollema, E Mara; van der Kley, Frank; de Weger, Arend; Ajmone Marsan, Nina; Naji, Franjo; Fras, Zlatko; Bax, Jeroen J; Delgado, Victoria

    2018-01-01

    Accurate aortic annulus sizing is key for selection of appropriate transcatheter aortic valve implantation (TAVI) prosthesis size. The present study compared novel automated 3-dimensional (3D) transesophageal echocardiography (TEE) software and multidetector row computed tomography (MDCT) for aortic annulus sizing and investigated the influence of the quantity of aortic valve calcium (AVC) on the selection of TAVI prosthesis size. A total of 83 patients with severe aortic stenosis undergoing TAVI were evaluated. Maximal and minimal aortic annulus diameter, perimeter, and area were measured. AVC was assessed with computed tomography. The low and high AVC burden groups were defined according to the median AVC score. Overall, 3D TEE measurements slightly underestimated the aortic annulus dimensions as compared with MDCT (mean differences between maximum, minimum diameter, perimeter, and area: -1.7 mm, 0.5 mm, -2.7 mm, and -13 mm 2 , respectively). The agreement between 3D TEE and MDCT on aortic annulus dimensions was superior among patients with low AVC burden (AVC burden (≥3,025 arbitrary units). The interobserver variability was excellent for both methods. 3D TEE and MDCT led to the same prosthesis size selection in 88%, 95%, and 81% of patients in the total population, the low, and the high AVC burden group, respectively. In conclusion, the novel automated 3D TEE imaging software allows accurate and highly reproducible measurements of the aortic annulus dimensions and shows excellent agreement with MDCT to determine the TAVI prosthesis size, particularly in patients with low AVC burden. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-08-15

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

  20. Threshold-dependent variability of coronary artery calcification measurements - implications for contrast-enhanced multi-detector row-computed tomography

    International Nuclear Information System (INIS)

    Moselewski, Fabian; Ferencik, Maros; Achenbach, Stephan; Abbara, Suhny; Cury, Ricardo C.; Booth, Sarah L.; Jang, Ik-Kyung; Brady, Thomas J.; Hoffmann, Udo

    2006-01-01

    Introduction: The present study investigated the threshold-dependent variability of coronary artery calcification (CAC) measurements and the potential to quantify CAC in contrast-enhanced multi-detector row-computed tomography (MDCT). Methods: We compared the mean CT attenuation of CAC to luminal contrast enhancement of the coronary arteries in 30 patients (n = 30) undergoing standard coronary contrast-enhanced spiral MDCT. The modified Agatston score [AS], calcified plaque volume [CV], and mineral mass [MM]) at four different thresholds (130, 200, 300, and 400 HU) were measured in 50 patients who underwent non-contrast-enhanced MDCT. Results: Mean CT attenuation of CAC was similar to the attenuation of the contrast-enhanced coronary lumen (CAC 297.1 ± 68.7 HU versus 295 ± 65 HU (p < 0.0001), respectively). Above a threshold of 300 HU CAC measurements significantly varied to standard measurements obtained at a threshold of 130 HU (p < 0.0001). The threshold-dependent variation of MM measurements was significantly smaller than for AS and CV (130 HU versus 400 HU: 63, 75, and 81, respectively; p < 0.001). These differences resulted in a change of age and gender based percentile category for AS in 78% of subjects. Discussion: We demonstrated that CAC measurements are threshold dependent with MM measurements having significantly less variation than AS or CV. Due to the similarity of mean CT attenuation of CAC and the contrast-enhanced coronary lumen accurate quantification of CAC may be difficult in standard coronary contrast-enhanced spiral MDCT

  1. Whole tumour first-pass perfusion using a low-dose method with 64-section multidetector row computed tomography in oesophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Chen Tianwu; Yang Zhigang; Dong Zhihui; Li Yuan; Yao Jin; Wang Qiling; Qian Lingling

    2011-01-01

    Purpose: To propose a low-dose method at tube current-time product of 50 mAs for whole tumour first-pass perfusion of oesophageal squamous cell carcinoma using 64-section multidetector row computed tomography (MDCT), and to assess the original image quality and accuracy of perfusion parameters. Materials and methods: Fifty-nine consecutive patients with confirmed oesophageal squamous cell carcinomas were enrolled into our study, and underwent whole tumour first-pass perfusion scan with 64-section MDCT at 50 mAs. Image data were statistically reviewed focusing on original image quality demonstrated by image-quality scores and signal-to-noise (S/N) ratios; and perfusion parameters including perfusion (PF, in ml/min/ml), peak enhanced density (PED, in HU), time to peak (TTP, in seconds) and blood volume (BV, in ml/100 g) for the tumour. To test the interobserver agreement of perfusion measurements, perfusion analyses were repeatedly performed. Results: Original image-quality scores were 4.71 ± 0.49 whereas S/N ratios were 5.21 ± 2.05, and the scores were correlated with the S/N ratios (r = 0.465, p < 0.0001). Mean values for PF, PED, TTP and BV of the tumour were 33.27 ± 24.15 ml/min/ml, 24.06 ± 9.87 HU, 29.42 ± 8.61 s, and 12.45 ± 12.22 ml/100 g, respectively. Intraclass correlation coefficient between the replicated measurements of each perfusion parameter was greater than 0.99, and mean difference of the replicated measurements of each parameter was close to zero. Conclusion: Whole tumour first-pass perfusion with 64-section MDCT at low-dose radiation could be reproducible to assess microcirculation in oesophageal squamous cell carcinoma without compromising subjective original image quality of the tumour.

  2. Preoperative differentiation between T1a and ≥T1b gallbladder cancer: combined interpretation of high-resolution ultrasound and multidetector-row computed tomography

    International Nuclear Information System (INIS)

    Joo, Ijin; Baek, Jee Hyun; Kim, Jung Hoon; Han, Joon Koo; Choi, Byung Ihn; Lee, Jae Young; Park, Hee Sun

    2014-01-01

    To determine the diagnostic value of combined interpretation of high-resolution ultrasound (HRUS) and multidetector-row computed tomography (MDCT) for preoperative differentiation between T1a and ≥T1b gallbladder (GB) cancer. Eighty-seven patients with pathologically confirmed GB cancers (T1a, n = 15; ≥T1b, n = 72), who preoperatively underwent both HRUS and MDCT, were included in this retrospective study. Two reviewers independently determined the T-stages of the GB cancers on HRUS and MDCT using a five-point confidence scale (5, definitely T1a; 1, definitely ≥T1b). For individual modality interpretation, the lesions with scores ≥4 were classified as T1a, and, for combined modality interpretation, the lesions with all scores ≥4 in both modalities were classified as T1a. The McNemar test was used to compare diagnostic performance. The diagnostic accuracy of differentiation between T1a and ≥T1b GB cancer was higher using combined interpretation (90.8 % and 88.5 % for reviewers 1 and 2, respectively) than individual interpretation of HRUS (82.8 % and 83.9 %) or MDCT (74.7 % and 82.8 %) (P < 0.05, reviewer 1). Combined interpretations demonstrated 100 % specificity for both reviewers, which was significantly higher than individual interpretations (P < 0.05, both reviewers). Combined HRUS and MDCT interpretation may improve the diagnostic accuracy and specificity for differentiating between T1a and ≥T1b GB cancers. circle Differentiating between T1a and ≥T1b gallbladder cancer can help surgical planning. (orig.)

  3. Threshold-dependent variability of coronary artery calcification measurements - implications for contrast-enhanced multi-detector row-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Moselewski, Fabian [Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Ferencik, Maros [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Achenbach, Stephan [Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Department of Internal Medicine II (Cardiology), University of Erlangen (Germany); Abbara, Suhny [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Cury, Ricardo C. [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Booth, Sarah L. [Jean Mayer USDA Human Nutrition Research Center on Aging, 711 Washington St., Boston, MA 02114 (United States); Jang, Ik-Kyung [Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Brady, Thomas J. [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Hoffmann, Udo [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States)]. E-mail: uhoffman@partners.org

    2006-03-15

    Introduction: The present study investigated the threshold-dependent variability of coronary artery calcification (CAC) measurements and the potential to quantify CAC in contrast-enhanced multi-detector row-computed tomography (MDCT). Methods: We compared the mean CT attenuation of CAC to luminal contrast enhancement of the coronary arteries in 30 patients (n = 30) undergoing standard coronary contrast-enhanced spiral MDCT. The modified Agatston score [AS], calcified plaque volume [CV], and mineral mass [MM] at four different thresholds (130, 200, 300, and 400 HU) were measured in 50 patients who underwent non-contrast-enhanced MDCT. Results: Mean CT attenuation of CAC was similar to the attenuation of the contrast-enhanced coronary lumen (CAC 297.1 {+-} 68.7 HU versus 295 {+-} 65 HU (p < 0.0001), respectively). Above a threshold of 300 HU CAC measurements significantly varied to standard measurements obtained at a threshold of 130 HU (p < 0.0001). The threshold-dependent variation of MM measurements was significantly smaller than for AS and CV (130 HU versus 400 HU: 63, 75, and 81, respectively; p < 0.001). These differences resulted in a change of age and gender based percentile category for AS in 78% of subjects. Discussion: We demonstrated that CAC measurements are threshold dependent with MM measurements having significantly less variation than AS or CV. Due to the similarity of mean CT attenuation of CAC and the contrast-enhanced coronary lumen accurate quantification of CAC may be difficult in standard coronary contrast-enhanced spiral MDCT.

  4. Use of multidetector-row computed tomography scan to detect pannus formation in prosthetic mechanical aortic valves.

    Science.gov (United States)

    Aladmawi, Mohamed A; Pragliola, Claudio; Vriz, Olga; Galzerano, Domenico

    2017-04-01

    Obstruction of a mechanical aortic valve by pannus formation at the subvalvular level is a major long-term complication of aortic valve replacement (AVR). In fact, pannus is sometime difficult to differentiate from patient-prosthesis mismatch or valve thrombosis. In most cases cine-angiography and echocardiography, either transthoracic or transesophageal, cannot correctly visualize the complication when the leaflets show a normal mobility. Recent technological refinements made this difficult diagnosis possible by ECG-gated computed tomography (CT) scan which shows adequate images in 90% of the cases and can differentiate pannus from fresh and organized thrombus.

  5. Estimation of aortic time-enhancement curve in pharmacokinetic analysis. Dynamic study by multi-detector row computed tomography

    International Nuclear Information System (INIS)

    Yamaguchi, Isao; Kidoya, Eiji; Higashimura, Kyoji; Hayashi, Hiroyuki; Suzuki, Masayuki

    2007-01-01

    This paper presents an introduction to the development of software that provides a physiologic model of contrast medium enhancement by incorporating available physiologic data and contrast medium pharmacokinetics to predict an organ-specific aortic time-enhancement curve (TEC) in computed tomography (CT) with various contrast medium injection protocols in patients of various heights, weights, cardiac output levels, and so on. The physiologic model of contrast medium enhancement was composed of six compartments for early contrast enhancement pharmacokinetics. Contrast medium is injected via the antecubital vein and distributed to the right side of the heart, the pulmonary compartment, the left side of the heart, and the aorta. It then circulates back to the right side of the heart via the systemic circulation. A computer-based, compartmental model of the aortic system was generated using human physiologic parameters and six differential equations to describe the transport of contrast medium. Aortic TEC generated by the computer-based physiologic model of contrast medium enhancement showed validity and agreement with clinical data and findings published previously. A computer-based physiologic model that may help predict organ-specific CT contrast medium enhancement for different injection protocols was developed. Such a physiologic model may have multiple clinical applications. (author)

  6. Measurement of cardiac ventricular volumes using multidetector row computed tomography: comparison of two- and three-dimensional methods

    International Nuclear Information System (INIS)

    Montaudon, M.; Laffon, E.; Berger, P.; Corneloup, O.; Latrabe, V.; Laurent, F.

    2006-01-01

    This study compared a three-dimensional volumetric threshold-based method to a two-dimensional Simpson's rule based short-axis multiplanar method for measuring right (RV) and left ventricular (LV) volumes, stroke volumes, and ejection fraction using electrocardiography-gated multidetector computed tomography (MDCT) data sets. End-diastolic volume (EDV) and end-systolic volume (ESV) of RV and LV were measured independently and blindly by two observers from contrast-enhanced MDCT images using commercial software in 18 patients. For RV and LV the three-dimensionally calculated EDV and ESV values were smaller than those provided by two-dimensional short axis (10%, 5%, 15% and 26% differences respectively). Agreement between the two methods was found for LV (EDV/ESV: r=0.974/0.910, ICC=0.905/0.890) but not for RV (r=0.882/0.930, ICC=0.663/0.544). Measurement errors were significant only for EDV of LV using the two-dimensional method. Similar reproducibility was found for LV measurements, but the three-dimensional method provided greater reproducibility for RV measurements than the two-dimensional. The threshold value supported three-dimensional method provides reproducible cardiac ventricular volume measurements, comparable to those obtained using the short-axis Simpson based method. (orig.)

  7. Accuracy of multidetector row computed tomography for the detection of transplant vasculopathy: comparison with invasive coronary angiography and intravascular ultrasound

    International Nuclear Information System (INIS)

    Carrascosa, P.; Capunay, C.; Carrascosa, J.; Perrone, S.; Deviggiano, A.; Lopez, E.M.; Lev, G.; Garcia, M.J.

    2009-01-01

    Objective: To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for detection of luminal stenosis and cardiac allograft vasculopathy in comparison with coronary angiography (CA) and intravascular ultrasound (IVUS) respectively. Material and methods: Nineteen cardiac transplant patients scheduled for follow-up CA were included. MDCT coronary angiography was performed using a 16-row CT scanner within 7-14 days after CA and IVUS. Studies were analyzed by independent readers; two observers evaluated the CT datasets for the presence of coronary artery stenosis > 50% and allograft vasculopathy. Results: The sensitivity for detecting > 50% luminal stenosis was 80-88% and specificity, 98-99% and for detection of cardiac allograft vasculopathy, the sensitivity was 91-96% and specificity, 88-91%. Conclusion: In this preliminary series, our results indicate that MDCT coronary angiography was capable of detecting both significant coronary stenosis as well as diffuse intimal proliferation. This non-invasive procedure could be an alternative to CA and IVUS in the surveillance of heart transplant patients. (authors) [es

  8. Role of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in diagnosis and management of pancreatic cancer; comparison with multidetector row computed tomography, magnetic resonance imaging and endoscopic ultrasonography.

    Science.gov (United States)

    Ergul, N; Gundogan, C; Tozlu, M; Toprak, H; Kadıoglu, H; Aydin, M; Cermik, T F

    2014-01-01

    We aimed to analyze the contribution of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging to the diagnosis and management of pancreatic cancer compared with multidetector row computed tomography (MDCT), magnetic resonance imaging (MRI) and endoscopic ultrasonography (EUS). We retrospectively scanned the data of 52 patients who were referred for FDG PET/CT imaging for evaluation of pancreatic lesions greater than 10mm. The diagnostic performances of 4 imaging methods and the impact of PET/CT on the management of pancreatic cancer were defined. Pancreatic adenocarcinoma was diagnosed in 33 of 52 patients (63%), 15 patients had benign diseases of pancreas (29%), and 4 patients were normal (8%). Sensitivity and NPV of EUS and PET/CT were equal (100%) and higher than MDCT and MRI. Specificity, PPV and NPV of PET/CT were significantly higher than MDCT. However, sensitivities of two imaging methods were not significantly different. There was no significant difference between PET/CT and MRI and EUS for these values. When the cut-off value of SUVmax was 3.2, the most effective sensitivity and specificity values were obtained. PET/CT contributed to the management of pancreatic cancer in 30% of patients. FDG PET/CT is a valuable imaging method for the diagnosis and management of pancreatic cancer, especially when applied along with EUS as first line diagnostic tools. Copyright © 2013 Elsevier España, S.L. and SEMNIM. All rights reserved.

  9. Four-channel multidetector-row computed tomography in the evaluation of facial fractures - optimized parameters for acquisition and multiplanar reformation

    International Nuclear Information System (INIS)

    Omid, P. M.

    2002-08-01

    The first part of this thesis is designed to give the reader a comprehensive survey on the complex basic principles of computed tomography (CT), from the early beginning to the recent development of multidetector-row CT (MD-CT). Attention is focused on imaging of trauma in general and on imaging of facial fractures in particular. The second part of this thesis describes a clinical study performed to optimize acquisition protocols and multiplanar reformation (MPR) algorithms for the evaluation of facial fractures using MD-CT, which has not been yet described in literature. For this study, a cadaver head with artificial blunt facial trauma was examined using a 4-channel MD-CT scanner. The influence of acquisition parameters (collimation: 2x0.5 mm/4x1 mm/4x2.5 mm; tube current: 120 mAs/90 mAs/60 mAs), image reconstruction algorithms (standard vs. ultra-high resolution (UHR) modes; reconstructed slice thicknesses: 0.5 mm/1 mm/3 mm; increment: 0.3 mm/0.6 mm/1.5 mm), and reformation algorithms (slice thicknesses: 0.5 mm/1 mm/3 mm; overlap: 0.5 mm/1 mm/3 mm) on detectability of facial fractures in MPRs with MD-CT was analyzed. Effects of algorithms and parameters on image noise, artifacts and delineation of soft tissues were evaluated. The results of this study reliably demonstrate that fracture detection was significantly higher with thin MPRs (0.5/0.5 mm, 1/0.5 mm, 1/1 mm) (p = 0 .014) acquired with 2x0.5 mm collimation (p = 0 .046), in UHR mode (p .0005) with 120 mAs (p = 0 .025). Inter-observer variability showed very good agreement (κ > = 0 .942). Non-UHR mode, lower mAs and thick MPRs (3/0.5 mm, 3/1 mm, 3/0.5 mm) showed significantly decreased detectability. (author)

  10. Phantom-Calibrated versus Automatic Coronary Artery Mass Quantification with Multidetector-Row Computed Tomography: In Vitro and In Vivo Study

    Energy Technology Data Exchange (ETDEWEB)

    Serafin, Z.; Lasek, W.; Laskowska, K. (Dept. of Radiology and Diagnostic Imaging, Nicolaus Copernicus Univ., Collegium Medicum, Bydgoszcz (Poland))

    2008-11-15

    Background: Coronary artery calcium scoring is used as a method for cardiovascular risk stratification and monitoring of coronary heart disease. Automatic software-based calcium mass calculation has been proposed to improve the performance of the procedure. Purpose: To compare two algorithms of calcium mass measurement, automatic and phantom calibrated, with respect to correlation, measurement error, and accuracy in vitro and in vivo. Material and Methods: A cardiac phantom with calcium cylinder inserts was scanned with sequential non-overlapping collimation 4x2.5 mm, at 120 kV and 165 mAs. Fifty adults (37 men; mean age 46.2 years) were examined with the same settings using prospective electrocardiographic triggering to detect and quantify coronary artery calcifications. Calculations were performed with two methods: software-based automatic calcium mass measurement (ACM) and phantom-calibrated calcium mass measurement (CCM). Results: The total phantom calcium masses measured with ACM and CCM were 175.0+-13.8 mg and 163.0+-4.4 mg, respectively (P<0.0001), and ACM produced a higher mean error (4.5 vs. 3.2; P<0.05). Results of ACM and CCM were strongly correlated to each other (R=0.73-0.96; P<0.0001). Mean image noise in the patient study was 8.72+-1.68 HU. Results of patient calcium scoring with ACM and CCM were significantly different (median 70.3 mg and 59.7 mg, respectively; P<0.0001), with a mean systematic error of 17.5% (limit of agreement between 14.6% and 20.4%). The use of ACM resulted in an altered quartile classification for 14% of patients, as compared to CCM; all of these patients were classified into a higher category. Conclusion: Our data indicate that multidetector-row computed tomography coronary calcium mass determination based on dedicated phantom calibration shows lower measurement error than an automatic software-based calculation method. The tested automatic software does not yet seem to be a reliable option for calcium mass measurement

  11. Phantom-Calibrated versus Automatic Coronary Artery Mass Quantification with Multidetector-Row Computed Tomography: In Vitro and In Vivo Study

    International Nuclear Information System (INIS)

    Serafin, Z.; Lasek, W.; Laskowska, K.

    2008-01-01

    Background: Coronary artery calcium scoring is used as a method for cardiovascular risk stratification and monitoring of coronary heart disease. Automatic software-based calcium mass calculation has been proposed to improve the performance of the procedure. Purpose: To compare two algorithms of calcium mass measurement, automatic and phantom calibrated, with respect to correlation, measurement error, and accuracy in vitro and in vivo. Material and Methods: A cardiac phantom with calcium cylinder inserts was scanned with sequential non-overlapping collimation 4x2.5 mm, at 120 kV and 165 mAs. Fifty adults (37 men; mean age 46.2 years) were examined with the same settings using prospective electrocardiographic triggering to detect and quantify coronary artery calcifications. Calculations were performed with two methods: software-based automatic calcium mass measurement (ACM) and phantom-calibrated calcium mass measurement (CCM). Results: The total phantom calcium masses measured with ACM and CCM were 175.0±13.8 mg and 163.0±4.4 mg, respectively (P<0.0001), and ACM produced a higher mean error (4.5 vs. 3.2; P<0.05). Results of ACM and CCM were strongly correlated to each other (R=0.73-0.96; P<0.0001). Mean image noise in the patient study was 8.72±1.68 HU. Results of patient calcium scoring with ACM and CCM were significantly different (median 70.3 mg and 59.7 mg, respectively; P<0.0001), with a mean systematic error of 17.5% (limit of agreement between 14.6% and 20.4%). The use of ACM resulted in an altered quartile classification for 14% of patients, as compared to CCM; all of these patients were classified into a higher category. Conclusion: Our data indicate that multidetector-row computed tomography coronary calcium mass determination based on dedicated phantom calibration shows lower measurement error than an automatic software-based calculation method. The tested automatic software does not yet seem to be a reliable option for calcium mass measurement

  12. Multidetector-row computed tomography in the preoperative diagnosis of intestinal complications caused by clinically unsuspected ingested dietary foreign bodies: a case series emphasizing the use of volume rendering techniques

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Augusto Cesar Vieira; Torres, Ulysses dos Santos; Oliveira, Eduardo Portela de; Gual, Fabiana; Bauab Junior, Tufik, E-mail: usantor@yahoo.com.br [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Hospital de Base. Serv. de Radiologia e Diagnostico por Imagem; Westin, Carlos Eduardo Garcia [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Hospital de Base. Cirurgia Geral; Cardoso, Luciana Vargas [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Hospital de Base. Setor de Tomografia Computadorizada

    2013-11-15

    Objective: the present study was aimed at describing a case series where a preoperative diagnosis of intestinal complications secondary to accidentally ingested dietary foreign bodies was made by multidetector-row computed tomography (MDCT), with emphasis on complementary findings yielded by volume rendering techniques (VRT) and curved multiplanar reconstructions (MPR). Materials and Methods: The authors retrospectively assessed five patients with surgically confirmed intestinal complications (perforation and/or obstruction) secondary to unsuspected ingested dietary foreign bodies, consecutively assisted in their institution between 2010 and 2012. Demographic, clinical, laboratory and radiological data were analyzed. VRT and curved MPR were subsequently performed. Results: preoperative diagnosis of intestinal complications was originally performed in all cases. In one case the presence of a foreign body was not initially identified as the causal factor, and the use of complementary techniques facilitated its retrospective identification. In all cases these tools allowed a better depiction of the entire foreign bodies on a single image section, contributing to the assessment of their morphology. Conclusion: although the use of complementary techniques has not had a direct impact on diagnostic performance in most cases of this series, they may provide a better depiction of foreign bodies' morphology on a single image section. (author)

  13. Accurate estimation of global and regional cardiac function by retrospectively gated multidetector row computed tomography. Comparison with cine magnetic resonance imaging

    International Nuclear Information System (INIS)

    Belge, Benedicte; Pasquet, Agnes; Vanoverschelde, Jean-Louis J.; Coche, Emmanuel; Gerber, Bernhard L.

    2006-01-01

    Retrospective reconstruction of ECG-gated images at different parts of the cardiac cycle allows the assessment of cardiac function by multi-detector row CT (MDCT) at the time of non-invasive coronary imaging. We compared the accuracy of such measurements by MDCT to cine magnetic resonance (MR). Forty patients underwent the assessment of global and regional cardiac function by 16-slice MDCT and cine MR. Left ventricular (LV) end-diastolic and end-systolic volumes estimated by MDCT (134±51 and 67±56 ml) were similar to those by MR (137±57 and 70±60 ml, respectively; both P=NS) and strongly correlated (r=0.92 and r=0.95, respectively; both P<0.001). Consequently, LV ejection fractions by MDCT and MR were also similar (55±21 vs. 56±21%; P=NS) and highly correlated (r=0.95; P<0.001). Regional end-diastolic and end-systolic wall thicknesses by MDCT were highly correlated (r=0.84 and r=0.92, respectively; both P<0.001), but significantly lower than by MR (8.3±1.8 vs. 8.8±1.9 mm and 12.7±3.4 vs. 13.3±3.5 mm, respectively; both P<0.001). Values of regional wall thickening by MDCT and MR were similar (54±30 vs. 51±31%; P=NS) and also correlated well (r=0.91; P<0.001). Retrospectively gated MDCT can accurately estimate LV volumes, EF and regional LV wall thickening compared to cine MR. (orig.)

  14. Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid (Gd-EOB-DTPA)-Enhanced Magnetic Resonance Imaging and Multidetector-Row Computed Tomography for the Diagnosis of Hepatocellular Carcinoma: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Ye, Feng; Liu, Jun; Ouyang, Han

    2015-08-01

    The purpose of this meta-analysis was to compare the diagnostic accuracy of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and multidetector-row computed tomography (MDCT) for hepatocellular carcinoma (HCC).Medline, Cochrane, EMBASE, and Google Scholar databases were searched until July 4, 2014, using combinations of the following terms: gadoxetic acid disodium, Gd-EOB-DTPA, multidetector CT, contrast-enhanced computed tomography, and magnetic resonance imaging. Inclusion criteria were as follows: confirmed diagnosis of primary HCC by histopathological examination of a biopsy specimen; comparative study of MRI using Gd-EOB-DTPA and MDCT for diagnosis of HCC; and studies that provided quantitative outcome data. The pooled sensitivity and specificity of the 2 methods were compared, and diagnostic accuracy was assessed with alternative-free response receiver-operating characteristic analysis.Nine studies were included in the meta-analysis, and a total of 1439 lesions were examined. The pooled sensitivity and specificity for 1.5T MRI were 0.95 and 0.96, respectively, for 3.0T MRI were 0.91 and 0.96, respectively, and for MDCT were 0.74 and 0.93, respectively. The pooled diagnostic odds ratio for 1.5T and 3.0T MRI was 242.96, respectively, and that of MDCT was 33.47. To summarize, Gd-EOB-DTPA-enhanced MRI (1.5T and 3.0T) has better diagnostic accuracy for HCC than MDCT.

  15. Dose-reduced 16-slice multidetector-row spiral computed tomography in children with bronchoscopically suspected vascular tracheal stenosis - initial results

    International Nuclear Information System (INIS)

    Honnef, D.; Wildberger, J.E.; Das, M.; Hohl, C.; Mahnken, A.; Guenther, R.W.; Staatz, G.; Schnoering, H.; Vazquez-Jimenez, J.

    2006-01-01

    Purpose: To evaluate the diagnostic accuracy of contrast-enhanced dose-reduced 16-slice multidetector-row CT (MDCT) in newborns and infants with fiberoptic bronchoscopically suspected vascular-induced tracheal stenosis. Materials and Methods: 12 children (4 days to 3 years, 1.2-13.5 kg body weight) were examined using i.v. contrast-enhanced 16-slice MDCT (SOMATOM Sensation 16, Forchheim, Germany) without breath-hold and under sedation (11/12). All MDCTs were performed with a dose reduction. The beam collimation was 16 x 0.75 mm, except in the case of one child. MPRs along the tracheal axis in the x-, y- and z-directions and volume-rendering-reconstructions (VRTs) were calculated based on a secondary raw data set in addition to conventional axial slices. 2 radiologists used a three-point grade scale to evaluate the image quality, motion, and contrast media artifacts as well as the usefulness of the 2D- and 3D-reconstructions for determining the diagnosis. Statistical analysis was performed on the basis of a Kappa test. Results: In all cases the cause of the fiberoptic bronchoscopically suspected tracheal stenosis was revealed: compression due to the brachiocephalic trunk (n=7), double aortic arch (n=2), lusorian artery (n=1), vascular compression of the left main bronchus (n=2). In 3 patients further thoracic anomalies, such as tracheobronchial (n=2), and vascular (n=2) and vertebral (n=1) anomalies were found. The attenuation in the anomalous vessels was 307±140 HU. The image noise was 9.8±1.9 HU. The mean dose reduction was 82.7±3.2% compared to a standard adult thoracic CT. All examinations were rated as diagnostically good (median 1, range 1, k=1). 3D images did not show any stair artifacts (median 2, range 1-2, k=1). The image noise was minor to moderate and hardly any motion artifacts were seen (median 1, range 1-2, k=0.8). Contrast media artifacts were rated zero to minor (median 1.5, range 1-2, k=0.676). MPRs (median 1, range 1, k=1) and VRTs (median 1

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  17. Multidetector-Row Computed Tomography in the Evaluation of Transjugular Intrahepatic Portosystemic Shunt Performed with Expanded-Polytetrafluoroethylene-Covered Stent-Graft

    International Nuclear Information System (INIS)

    Fanelli, Fabrizio; Bezzi, Mario; Bruni, Antonio; Corona, Mario; Boatta, Emanuele; Lucatelli, Pierleone; Passariello, Roberto

    2011-01-01

    We assessed, in a prospective study, the efficacy of multidetector spiral computed tomography (MDCT) in the evaluation of transjugular intrahepatic portosystemic shunt (TIPS) patency in patients treated with the Viatorr (Gore, Flagstaff, AZ) expanded-polytetrafluoroethylene (e-PTFE)-covered stent-graft. Eighty patients who underwent TIPS procedure using the Viatorr self-expanding e-PTFE stent-graft were evaluated at follow-up of 1, 3, 6, and 12 months with clinical and laboratory tests as well as ultrasound–color Doppler (USCD) imaging. In case of varices, upper gastrointestinal endoscopy was also performed. In addition, the shunt was evaluated using MDCT at 6 and 12 months. In all cases of abnormal findings and discrepancy between MDCT and USCD, invasive control venography was performed. MDCT images were acquired before and after injection of intravenous contrast media on the axial plane and after three-dimensional reconstruction using different algorithms. MDCT was successfully performed in all patients. No artefacts correlated to the Viatorr stent-graft were observed. A missing correlation between UCSD and MDCT was noticed in 20 of 80 (25%) patients. Invasive control venography confirmed shunt patency in 16 (80%) cases and shunt malfunction in 4 (20%) cases. According to these data, MDCT sensitivity was 95.2%; specificity was 96.6%; and positive (PPV) and negative predictive values (NPV) were 90.9 and 98.2%, respectively. USCD sensitivity was 90%; specificity was 75%; and PPV and NPV were 54.5 and 95.7%, respectively. A high correlation (K value = 0.85) between MDCT and invasive control venography was observed. On the basis of these results, MDCT shows superior sensitivity and specificity compared with USCD in those patients in whom TIPS was performed with the Viatorr stent-graft. MDCT can be considered a valid tool in the follow-up of these patients.

  18. Lung surgery assisted by multidetector-row computed tomographic simulation

    International Nuclear Information System (INIS)

    Oizumi, Hiroyuki; Endoh, Makoto; Ota, Hiroshi; Takeda, Shinichi; Suzuki, Jun; Fukaya, Ken; Chiba, Masato; Sadahiro, Mitsuaki

    2009-01-01

    We describe the benefits of lung resection simulation using multidetector computed tomography (MDCT). Since 2004, the 1.0-mm slice digital imaging and communications in medicine (DICOM) server has been used for storing data obtained using 64-row MDCT. We observed that an abnormality could not be visualized from the pleural surface in 10 nodules of 18 lesions undergoing wedge lung resection. These 10 nodules were resected through simulation using a three-dimensional (3D) volume-rendering method by considering parameters such as the position, depth, or distance from the interlobar abnormalities, etc., without the need for any marking methods. For lung lobectomy, identification of the branching structures, diameter, and length of the arteries is useful in selecting the procedure for blood vessel treatment. However, in the initial 10 patients of this series, the preoperative identification of 2 small arterial branches was unsuccessful when this method was used. Therefore, it is important to carefully examine the original data in all 3 views, id est (i.e.), axial, sagittal, and coronal views. The visualization of venous branches in affected segments and intersegmental veins has facilitated the preoperative determination of the anatomical intersegmental plane. We divided the cases of thoracoscopic lung segmentectomy into 3 groups (level 1: simple, level 2: intermediate, and level 3: complex) on the basis of the technical complexity. Only level 1 segmentectomies were performed without MDCT simulation. Further, level 2 and 3 segmentectomies could be successfully performed because of the introduction of MDCT simulation in 25 of 35 patients. Thus, this simulation technique may be useful during a thoracoscopic procedure for lung surgery. (author)

  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...... that compares the diagnostic accuracy of multi-detector row computed tomography with that of coronary angiography Udgivelsesdato: 2009/4/6...

  20. The detectability of the origin of the inferior phrenic artery by paging method on multidetector-row CT angiography

    International Nuclear Information System (INIS)

    Terayama, Koshi

    2005-01-01

    We evaluated the ability to detect the origin of the inferior phrenic artery (IPA) by paging method on multidetector-row computed tomography (CT) angiography. In 104 patients who underwent multidetector-row CT, detectability of the origin of the IPA was assessed. In addition, in 30 patients in whom arteriographic study was performed, the IPA findings on multidetector-row CT were compared with those on arteriography. In 100 patients (96%) the origin of the right IPA was demonstrated with multidetector-row CT and in 93 patients (89%) the origin of the left IPA was demonstrated. CT angiographic findings concurred with arteriographic findings in all 30 patients (100%) who underwent arteriographic study. In conclusion, paging method on multidetector-row CT angiography provides valuable anatomical information regarding IPA. (author)

  1. Multi-detector row computed tomographic evaluation of a rare type of complete vascular ring: Double aortic arch with atretic left arch distal to the origin of left subclavian artery

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Ying Ying; Fu, Ching Yun; Wei, Hao Ji; Tsai, I Chen; Chen, Clayton Chi Chang [Taichung Veterans General Hospital, Taichung (China)

    2013-10-15

    Double aortic arch with an atretic left arch distal to the origin of left subclavian artery was diagnosed with multi-detector row computed tomography (MDCT) in two children with dysphagia. This rare type of complete vascular ring is clinically important because it may be confused with right aortic arch in mirror imaging. Anatomic details of this rare type of complete vascular ring demonstrated on MDCT facilitated appropriate surgical treatment.

  2. Comparison of the Multidetector-row Computed Tomographic Angiography Axial and Coronal Planes' Usefulness for Detecting Thoracodorsal Artery Perforators

    Science.gov (United States)

    Kim, Jong Gyu

    2012-01-01

    Background During the planning of a thoracodorsal artery perforator (TDAP) free flap, preoperative multidetector-row computed tomographic (MDCT) angiography is valuable for predicting the locations of perforators. However, CT-based perforator mapping of the thoracodorsal artery is not easy because of its small diameter. Thus, we evaluated 1-mm-thick MDCT images in multiple planes to search for reliable perforators accurately. Methods Between July 2010 and October 2011, 19 consecutive patients (13 males, 6 females) who underwent MDCT prior to TDAP free flap operations were enrolled in this study. Patients ranged in age from 10 to 75 years (mean, 39.3 years). MDCT images were acquired at a thickness of 1 mm in the axial, coronal, and sagittal planes. Results The thoracodorsal artery perforators were detected in all 19 cases. The reliable perforators originating from the descending branch were found in 14 cases, of which 6 had transverse branches. The former were well identified in the coronal view, and the latter in the axial view. The location of the most reliable perforators on MDCT images corresponded well with the surgical findings. Conclusions Though MDCT has been widely used in performing the abdominal perforator free flap for detecting reliable perforating vessels, it is not popular in the TDAP free flap. The results of this study suggest that multiple planes of MDCT may increase the probability of detecting the most reliable perforators, along with decreasing the probability of missing available vessels. PMID:22872839

  3. Accessory Renal Artery Stenosis and Hypertension: Are These Correlated? Evaluation Using Multidetector-Row Computed Tomographic Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saba, L.; Sanfilippo, R.; Montisci, R.; Conti, M.; Mallarini, G. (Dept. of Imaging Science and Dept. of Vascular Surgery, Policlinico Universitario, Cagliari (Italy))

    2008-04-15

    Background: Renal artery stenosis may produce hypertension, and this condition is referred to as renovascular hypertension (RVH). Purpose: To evaluate, by using multidetector-row spiral computed tomographic angiography (MDCTA), whether a relationship between accessory renal artery stenosis and hypertension may be hypothesized. Material and Methods: 214 patients (142 males, 72 females; mean age 66 years) who had previously undergone an MDCTA to study the abdominal vasculature were retrospectively studied. Patients with renal artery stenosis (RAS) were excluded from this analysis. The patients were studied by means of a four-detector-row CT, and scans were obtained after intravenous bolus administration of 110-140 ml of a nonionic contrast material with a 3-6 ml/s flow rate. As a second step, by means of statistical analysis, hypertension data were compared with findings of accessory artery stenosis. Two radiologists first independently reviewed the MDCTA images and then, in case of disagreement, in consensus. Interobserver agreement was calculated for all measurements. Results: The overall number of detected accessory renal arteries was 74 in 56 of the 214 patients. Accessory renal artery stenosis was detected in 21 of the 56 patients. There was a difference in the prevalence of hypertension between patients with (n = 21) and without (n = 35) accessory renal artery stenosis (P = 0.0187). Interobserver agreement was good (kappa value 0.733). Conclusion: Any statistical association between the presence of accessory renal artery stenosis and hypertension could not be disclosed. However, accessory renal artery stenosis, detected by MDCTA, is an important pathological sign that the radiologist has to assess in the light of its possible association with hypertension

  4. Accessory Renal Artery Stenosis and Hypertension: Are These Correlated? Evaluation Using Multidetector-Row Computed Tomographic Angiography

    International Nuclear Information System (INIS)

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

    2008-01-01

    Background: Renal artery stenosis may produce hypertension, and this condition is referred to as renovascular hypertension (RVH). Purpose: To evaluate, by using multidetector-row spiral computed tomographic angiography (MDCTA), whether a relationship between accessory renal artery stenosis and hypertension may be hypothesized. Material and Methods: 214 patients (142 males, 72 females; mean age 66 years) who had previously undergone an MDCTA to study the abdominal vasculature were retrospectively studied. Patients with renal artery stenosis (RAS) were excluded from this analysis. The patients were studied by means of a four-detector-row CT, and scans were obtained after intravenous bolus administration of 110-140 ml of a nonionic contrast material with a 3-6 ml/s flow rate. As a second step, by means of statistical analysis, hypertension data were compared with findings of accessory artery stenosis. Two radiologists first independently reviewed the MDCTA images and then, in case of disagreement, in consensus. Interobserver agreement was calculated for all measurements. Results: The overall number of detected accessory renal arteries was 74 in 56 of the 214 patients. Accessory renal artery stenosis was detected in 21 of the 56 patients. There was a difference in the prevalence of hypertension between patients with (n = 21) and without (n = 35) accessory renal artery stenosis (P = 0.0187). Interobserver agreement was good (kappa value 0.733). Conclusion: Any statistical association between the presence of accessory renal artery stenosis and hypertension could not be disclosed. However, accessory renal artery stenosis, detected by MDCTA, is an important pathological sign that the radiologist has to assess in the light of its possible association with hypertension

  5. Effect of computer-aided detection as a second reader in multidetector-row CT colonography

    International Nuclear Information System (INIS)

    Mang, Thomas; Peloschek, Philipp; Plank, Christina; Maier, Andrea; Weber, Michael; Herold, Christian; Schima, Wolfgang; Graser, Anno; Bogoni, Luca

    2007-01-01

    Our purpose was to assess the effect of computer-aided detection (CAD) on lesion detection as a second reader in computed tomographic colonography, and to compare the influence of CAD on the performance of readers with different levels of expertise. Fifty-two CT colonography patient data-sets (37 patients: 55 endoscopically confirmed polyps ≥0.5 cm, seven cancers; 15 patients: no abnormalities) were retrospectively reviewed by four radiologists (two expert, two nonexpert). After primary data evaluation, a second reading augmented with findings of CAD (polyp-enhanced view, Siemens) was performed. Sensitivities and reading time were calculated for each reader without CAD and supported by CAD findings. The sensitivity of expert readers was 91% each, and of nonexpert readers, 76% and 75%, respectively, for polyp detection. CAD increased the sensitivity of expert readers to 96% (P = 0.25) and 93% (P = 1), and that of nonexpert readers to 91% (P = 0.008) and 95% (P = 0.001), respectively. All four readers diagnosed 100% of cancers, but CAD alone only 43%. CAD increased reading time by 2.1 min (mean). CAD as a second reader significantly improves sensitivity for polyp detection in a high disease prevalence population for nonexpert readers. CAD causes a modest increase in reading time. CAD is of limited value in the detection of cancer. (orig.)

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  8. Multidetector row CT for imaging the paediatric tracheobronchial tree

    International Nuclear Information System (INIS)

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

    2007-01-01

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

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

    Science.gov (United States)

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

    2006-01-01

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

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

  11. Multidetector-row computed tomography imaging of prosthetic heart valves: clinical and experimental aspects

    NARCIS (Netherlands)

    Symersky, P.

    2012-01-01

    Tot voor kort had het afbeelden van hartklepprothesen (kunstkleppen) door middel van een CT-scan geen aanvullende waarde. Kunstkleppen zijn bewegende metalen objecten, en daardoor werden CT-beelden vervormd door artefacten en dubbelcontouren. De huidige CT-systemen kunnen echter vaak wel een

  12. Advanced Gastric Cancer and Perfusion Imaging Using a Multidetector Row Computed Tomography: Correlation with Prognostic Determinants

    International Nuclear Information System (INIS)

    Zhang, Huan; Pan, Zilai; Du, Lianjun; Yan, Chao; Ding, Bei; Song, Qi; Ling, Huawei; Chen, Kemin

    2008-01-01

    Objective : To investigate the relationship between the perfusion CT features and the clinicopathologically determined prognostic factors in advanced gastric cancer cases. Materials and Methods : A perfusion CT was performed on 31 patients with gastric cancer one week before surgery using a 16-channel multi-detector CT (MDCT) instrument. The data were analyzed with commercially available software to calculate tumor blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS). The microvessel density (MVD), was evaluated by immunohistochemical staining of the surgical specimens with anti-CD34. All of the findings were analyzed prospectively and correlated with the clinicopathological findings, which included histological grading, presence of lymph node metastasis, serosal involvement, distant metastasis, tumor, node, metastasis (TNM) staging, and MVD. The statistical analyses used included the Student's t-test and the Spearman rank correlation were performed in SPSS 11.5. Result : The mean perfusion values and MVD for tumors were as follows: BF (48.14+/-16.46 ml/100 g/min), BV (6.70+/-2.95 ml/100 g), MTT (11.75+/-4.02 s), PS (14.17+/-5.23 ml/100 g/min) and MVD (41.7+/-11.53). Moreover, a significant difference in the PS values was found between patients with or without lymphatic involvement (p = 0.038), as well as with different histological grades (p 0.04) and TNM stagings (p = 0.026). However, BF, BV, MTT, and MVD of gastric cancer revealed no significant relationship with the clinicopathological findings described above (p > 0.05). Conclusion : The perfusion CT values of the permeable surface could serve as a useful prognostic indicator in patients with advanced gastric cancer

  13. Advanced Gastric Cancer and Perfusion Imaging Using a Multidetector Row Computed Tomography: Correlation with Prognostic Determinants

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Huan; Pan, Zilai; Du, Lianjun; Yan, Chao; Ding, Bei; Song, Qi; Ling, Huawei; Chen, Kemin [Jiaotong University, Jiaotong (China)

    2008-04-15

    Objective : To investigate the relationship between the perfusion CT features and the clinicopathologically determined prognostic factors in advanced gastric cancer cases. Materials and Methods : A perfusion CT was performed on 31 patients with gastric cancer one week before surgery using a 16-channel multi-detector CT (MDCT) instrument. The data were analyzed with commercially available software to calculate tumor blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS). The microvessel density (MVD), was evaluated by immunohistochemical staining of the surgical specimens with anti-CD34. All of the findings were analyzed prospectively and correlated with the clinicopathological findings, which included histological grading, presence of lymph node metastasis, serosal involvement, distant metastasis, tumor, node, metastasis (TNM) staging, and MVD. The statistical analyses used included the Student's t-test and the Spearman rank correlation were performed in SPSS 11.5. Result : The mean perfusion values and MVD for tumors were as follows: BF (48.14+/-16.46 ml/100 g/min), BV (6.70+/-2.95 ml/100 g), MTT (11.75+/-4.02 s), PS (14.17+/-5.23 ml/100 g/min) and MVD (41.7+/-11.53). Moreover, a significant difference in the PS values was found between patients with or without lymphatic involvement (p = 0.038), as well as with different histological grades (p 0.04) and TNM stagings (p = 0.026). However, BF, BV, MTT, and MVD of gastric cancer revealed no significant relationship with the clinicopathological findings described above (p > 0.05). Conclusion : The perfusion CT values of the permeable surface could serve as a useful prognostic indicator in patients with advanced gastric cancer.

  14. Multidetector-row CT: economics and workflow

    International Nuclear Information System (INIS)

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

    2005-01-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  16. Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Takuro; Kurokawa, Yukinori; Takiguchi, Shuji; Miyazaki, Yasuhiro; Takahashi, Tsuyoshi; Yamasaki, Makoto; Miyata, Hiroshi; Nakajima, Kiyokazu; Mori, Masaki; Doki, Yuichiro [Osaka University, Graduate School of Medicine, Department of Gastroenterological Surgery, Suita, Osaka (Japan)

    2014-08-06

    The purpose of this study was to determine the optimal cut-off value of lymph node size for diagnosing metastasis in gastric cancer with multidetector-row computed tomography (MDCT) after categorizing perigastric lymph nodes into three regions. The study included 90 gastric cancer patients who underwent gastrectomy. The long-axis diameter (LAD) and short-axis diameter (SAD) of all visualized lymph nodes were measured with transverse MDCT images. The locations of lymph nodes were categorized into three regions: lesser curvature, greater curvature, and suprapancreatic. The diagnostic value of lymph node metastasis was assessed with receiver operating characteristic (ROC) analysis. The area under the curve was larger for SAD than LAD in all groups. The optimal cut-off values of SAD were determined as follows: overall, 9 mm; differentiated type, 9 mm; undifferentiated type, 8 mm; lesser curvature region, 7 mm; greater curvature region, 6 mm; and suprapancreatic region, 9 mm. The diagnostic accuracies for lymph node metastasis using individual cut-off values were 71.1 % based on histological type and 76.6 % based on region of lymph node location. The diagnostic accuracy of lymph node metastasis in gastric cancer was improved by using individual cut-off values for each lymph node region. (orig.)

  17. Detection, visualization and evaluation of anomalous coronary anatomy on 16-slice multidetector-row CT

    International Nuclear Information System (INIS)

    Ooijen, Peter M.A. van; Dorgelo, Joost; Oudkerk, Matthijs; Zijlstra, Felix

    2004-01-01

    Early identification and evaluation of relatively frequent anomalous coronary anatomy is quite relevant because of the occurrence of sudden cardiac death or related symptoms of myocardial ischemia. Selective coronary angiography (CAG) is invasive, expensive and cannot always provide the required information adequately. Recently, non-invasive imaging techniques such as magnetic resonance imaging and multidetector-row computed tomography (MDCT) have been shown to provide a good anatomical view of the coronary artery tree. This study aims to demonstrate the value of 16-MDCT for evaluation of anomalous coronary anatomy. In 13 patients scanned using 16-MDCT, six different coronary anomalies were diagnosed [two absent left main, one single vessel left coronary artery (LCA), three LCA originating from the right (two with interarterial course), six right coronary artery originating from the left, one double left anterior descending (LAD)]. Mean diagnostic quality, recorded by two observers using a 5-point scale (1= non-diagnostic to 5= excellent diagnostic quality), resulted in a mean score of 3.73 (SD 1.19) without any non-diagnostic result. MDCT offers an accurate diagnostic modality to visualize the origin and course of anomalous coronary arteries by a three-dimensional display of anatomy. Shortcomings in CAG can be overcome by the use of contrast-enhanced MDCT. (orig.)

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

  20. Utility of multidetector row computed tomography and virtual bronchoscopy in evaluation of hemoptysis due to lung cancer

    Directory of Open Access Journals (Sweden)

    Sherif A.A. Mohamed

    2016-01-01

    Conclusion: MDCT angiography is a useful and non invasive method that allows a rapid and detailed identification of abnormal vasculature responsible for hemoptysis in patients with lung cancer. MDCT-generated virtual bronchoscopy is an accurate, and non invasive method for evaluating obstructions, endoluminal masses, and external compressions in patients with hemoptysis due to lung cancer.

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-02-15

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

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  5. Sacroiliitis in Ankylosing Spondylitis: Comparison with Multidetector Row CT and Plain Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Ji Youn; Joo, Kyung Bin; Choi, Byeong Kyoo; Ryu, Jeong Ah; Kim, Tae Hwan; Choi, Woo Jung [Hanyang University Hospital, Seoul (Korea, Republic of)

    2009-03-15

    The objective of our study was to compare multidetector row CT and the plain radiographs for making the diagnosis and grading the sacroiliitis that accompanies ankylosing spondylitis. We wanted to determine the role of multidetector row CT for the evaluation of the sacroilitis in patients with ankylosing spondylitis. One hundred ninety two patients with clinically suspected ankylosing spondylitis were evaluated by conventional radiography and multidetector row CT. Two musculoskeletal radiologists retrospectively analyzed the images, and they graded the sacroiliitis using the modified New York Criteria. Multidetector row CT demonstrated a significantly higher sensitivity (74.5%, 83.3%) than did plain radiography (59.9%, 66.7%) for detecting early sacroiliitis (p<0.05). Multidetector row CT showed a higher grade of sacroiliitis in 114 and 127 of 384 sacroiliac joints. Performing multidetector row CT rather than plain radiography for making the diagnoses of accompanying ankylosing spondylitis allows an early start of treatment with a subsequently improved prognosis

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  7. Fusion of the midplane with the left intersectional plane: a liver anatomical variation revisited with multidetector-row CT

    International Nuclear Information System (INIS)

    Lucidarme, Olivier; Taboury, Jacques; Savier, Eric; Hannoun, Laurent; Cadi, Mehdi; Grenier, Philippe A.

    2006-01-01

    This article updates the description of an anatomical variation of the liver, in which the gallbladder is adjacent to the ligamentum teres, that was described until now as ''right-sided ligamentum teres and right umbilical portion of the portal vein''. A study of eight patients showing this anatomical variation has led to a new archetypal anatomical description of the hepatic and portal veins, using multidetector-row computed tomography (MDCT) with three-dimensional (3D) volume-rendering (VR) reconstructions. While 2D axial imaging gave the same information, MDCT imaging with VR reconstructions provided a clear 3D visualization of this anatomical variation. Typical features can be described as follows: (1) juxtaposition of the ligamentum teres and the gallbladder; (2) typical portal vein branching with a right posterior branch, a left posterior branch and a main medial branch that terminates in the ligamentum teres; (3) two main hepatic veins and a hypotrophied medial hepatic vein. We think, based on the direct comparison of anatomical findings and knowledge of chronological embryological development, that this abnormality results from the defective development of the central part of the liver and not from the persistence of the right rather than the left umbilical vein. Because of the presence of only one medial plane, containing both the gallbladder and the ligamentum teres, we propose renaming it ''fusion of hepatic planes''. (orig.)

  8. Radiological emergency room management with emphasis on multidetector-row

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-10-01

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

  9. Multidetector Computed Tomography in the Preoperative Workup of Hilar Cholangiocarcinoma

    International Nuclear Information System (INIS)

    Kim, Hyoung Jung; Lee, Dong Ho; Lim, Joo Won; Ko, Young Tae

    2009-01-01

    Hilar cholangiocarcinoma is associated with a dismal prognosis; however, curative resection may offer a chance of cure. Various factors should be considered in the surgical planning for curative resection. These factors include extent of bile duct involvement, relationship between portal vein and tumor involvement, diffuse hepato duodenal ligament infiltration, vascular invasion, lymph node metastasis, peritoneal seeding, and hepatic volume. Using high-quality volume data from multidetector-row computed tomography (MDCT) and adequate postprocessing images, radiologists can provide various types of information, imperative for curative resection of a hilar cholangiocarcinoma. This review illustrates the role of MDCT in the preoperative workup of hilar cholangiocarcinoma

  10. Traumatic thoracic injury: the role of Multidetector-row CT

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-05-15

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

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

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

    Science.gov (United States)

    Halliburton, Sandra Simon

    2009-11-01

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

  13. Breast multidetector-row CT with histopathologic correlation

    International Nuclear Information System (INIS)

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

    2004-01-01

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

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

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

    International Nuclear Information System (INIS)

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

    2002-01-01

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

  18. CT paging arteriography with a multidetector-row CT. Advantages in splanchnic arterial imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Seiji [Keio Univ., Tokyo (Japan). School of Medicine

    1999-11-01

    The purpose of this study is to assess the utility of CT paging arteriography with a multidetector-row CT as a replacement for conventional angiography in the evaluation of splanchnic arterial anomalies. Sixty-three patients underwent CT paging arteriography with a multidetector-row CT. In the 56 patients with conventional angiographic correlation, there was only one minor disagreement with CT paging arteriography. In the 7 patients who underwent IVDSA (intra venous digital subtraction angiography), CT paging arteriography defined four hepatic arterial anomalies which could not be depicted by IVDSA. In conclusion, CT paging arteriography provides noninvasive means to identify splanchnic arterial anomalies. (author)

  19. Non-invasive detection of aortic and coronary atherosclerosis in homozygous familial hypercholesterolemia by 64 slice multi-detector row computed tomography angiography

    Science.gov (United States)

    Homozygous familial hypercholesterolemia (HoFH) is a rare disorder characterized by the early onset of atherosclerosis, often at the ostia of coronary arteries. In this study we document for the first time that aortic and coronary atherosclerosis can be detected using 64 slice multiple detector row ...

  20. Evaluation to Obtain the Image According to the Spatial Domain Filtering of Various Convolution Kernels in the Multi-Detector Row Computed Tomography

    International Nuclear Information System (INIS)

    Lee, Hoo Min; Yoo, Beong Gyu; Kweon, Dae Cheol

    2008-01-01

    Our objective was to evaluate the image of spatial domain filtering as an alternative to additional image reconstruction using different kernels in MDCT. Derived from thin collimated source images were generated using water phantom and abdomen B10(very smooth), B20(smooth), B30(medium smooth), B40 (medium), B50(medium sharp), B60(sharp), B70(very sharp) and B80(ultra sharp) kernels. MTF and spatial resolution measured with various convolution kernels. Quantitative CT attenuation coefficient and noise measurements provided comparable HU(Hounsfield) units in this respect. CT attenuation coefficient(mean HU) values in the water were values in the water were 1.1∼1.8 HU, air(-998∼-1000 HU) and noise in the water(5.4∼44.8 HU), air(3.6∼31.4 HU). In the abdominal fat a CT attenuation coefficient(-2.2∼0.8 HU) and noise(10.1∼82.4 HU) was measured. In the abdominal was CT attenuation coefficient(53.3∼54.3 HU) and noise(10.4∼70.7 HU) in the muscle and in the liver parenchyma of CT attenuation coefficient(60.4∼62.2 HU) and noise (7.6∼63.8 HU) in the liver parenchyma. Image reconstructed with a convolution kernel led to an increase in noise, whereas the results for CT attenuation coefficient were comparable. Image scanned with a high convolution kernel(B80) led to an increase in noise, whereas the results for CT attenuation coefficient were comparable. Image medications of image sharpness and noise eliminate the need for reconstruction using different kernels in the future. Adjusting CT various kernels, which should be adjusted to take into account the kernels of the CT undergoing the examination, may control CT images increase the diagnostic accuracy.

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

    African Journals Online (AJOL)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-04-15

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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  4. Multidetector computer tomography in the pancreatic adenocarcinoma assessment: an update

    Directory of Open Access Journals (Sweden)

    Vincenza Granata

    2016-11-01

    Full Text Available Abstract Ductal adenocarcinoma of the pancreas is one of the most aggressive forms of cancer, with only a minority of cases being resectable at the moment of their diagnosis. The accurate detection and characterization of pancreatic carcinoma is very important for patient management. Multidetector-row computed tomography (MDCT has become the cross-sectional modality of choice in the diagnosis, staging, treatment planning, and follow-up of patients with pancreatic tumors. However, approximately 11% of ductal adenocarcinomas still remain undetected at MDCT because of the lack of attenuation gradient between the lesion and the adjacent pancreatic parenchyma. In this systematic literature review we investigate the current evolution of the CT technique, limitations, and perspectives in the evaluation of pancreatic carcinoma.

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

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

    Science.gov (United States)

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

    2003-10-01

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

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  9. Advanced Gastric Cancer: Differentiation of Borrmann Type IV versus Borrmann Type III by Two-Phased Dynamic Multi-Detector Row CT with Use of the Water Filling Method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Jung; Yu, Jeong Sik; Lee, Sang Min; Kim, Joo Hee; Chung, Jae Joon; Kim, Ki Whang [Dept. of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of); Kang, Hae Youn [CHA Bundang Medical Center, CHA University, Seongnam (Korea, Republic of)

    2013-02-15

    To characterize Borrmann type IV from Borrmann type III advanced gastric cancer (AGC) by two-phased multi-detector row computed tomography (MDCT) using the water filling method. A total of 143 patients (pathologically confirmed Borrmann type III and IV - 100 and 43 patients), who underwent preoperative MDCT, were enrolled. Two radiologists, retrospectively and independently, determined tumor enhancement pattern using a 5-grade scale without clinical information. A weighted kappa test was applied for interobserver variability. The score of tumor enhancement pattern correlated with Borrmann type as determined by Spearman's correlation coefficient. The accuracy of differentiation of Borrmann type using MDCT was determined by receiver operating characteristic curves. Interobserver agreement (weighted kappa = 0.683) was substantial. The tumor enhancement pattern score showed a significant correlation with Borrmann type (reviewer 1, r = 0.591, p < 0.001; reviewer 2, r = 0.616, p < 0.001). The accuracy for differentiation of Borrmann type on MDCT was 0.86 (p < 0.001) in both reviewers. The sensitivity and specificity of the diagnosis of Borrmann type IV were 79% and 82% in reviewer 1, and 88% and 78% in reviewer 2, respectively. Dual-phased MDCT using the water filling method can differentiate between Borrmann type IV and III AGC with high accuracy.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-02-15

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

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-09-15

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

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-11-15

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

  15. Intra- and interobserver agreement of computed tomography in assessment of the mandibular condyle

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Bong Hae; Jung, Yun Hoa [Pusan National Univ. College of Dentistry, Pusan (Korea, Republic of)

    2007-12-15

    To study the intra- and interobserver agreement of multidetector row computed tomography (MDCT) in interpretation of degenerative changes of the mandibular condyle. Five observers independently evaluated one hundred temporomandibular joint MDCT images for signs of osteophytes, erosion, sclerosis and flattening. The intra- and interobserve agreements were calculated by using Kappa statistics. The intraobserver agreement was substantial for erosion (k=0.75), flattening (k=0.74) and sclerosis (k=0.72) and almost perfect for osteophytes (k=0.84). The interobserver agreement was fair for flattening (k=0.39), moderate for erosion (k=0.58) and sclerosis (k=0.48) and substantial for osteophytes (k=0.75). This study shows that we can expert good agreement for the presence of osteophytes, but not for flattening in the interpretation of MDCT images of the condyle.

  16. 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.)

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-08-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    International Nuclear Information System (INIS)

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

    2003-01-01

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

  2. Computed tomography

    International Nuclear Information System (INIS)

    Wells, P.; Davis, J.; Morgan, M.

    1994-01-01

    X-ray or gamma-ray transmission computed tomography (CT) is a powerful non-destructive evaluation (NDE) technique that produces two-dimensional cross-sectional images of an object without the need to physically section it. CT is also known by the acronym CAT, for computerised axial tomography. This review article presents a brief historical perspective on CT, its current status and the underlying physics. The mathematical fundamentals of computed tomography are developed for the simplest transmission CT modality. A description of CT scanner instrumentation is provided with an emphasis on radiation sources and systems. Examples of CT images are shown indicating the range of materials that can be scanned and the spatial and contrast resolutions that may be achieved. Attention is also given to the occurrence, interpretation and minimisation of various image artefacts that may arise. A final brief section is devoted to the principles and potential of a range of more recently developed tomographic modalities including diffraction CT, positron emission CT and seismic tomography. 57 refs., 2 tabs., 14 figs

  3. Computed tomography

    International Nuclear Information System (INIS)

    Andre, M.; Resnick, D.

    1988-01-01

    Computed tomography (CT) has matured into a reliable and prominent tool for study of the muscoloskeletal system. When it was introduced in 1973, it was unique in many ways and posed a challenge to interpretation. It is in these unique features, however, that its advantages lie in comparison with conventional techniques. These advantages will be described in a spectrum of important applications in orthopedics and rheumatology

  4. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography (CT) of the sinuses ... CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known ...

  5. Illustrated computer tomography

    International Nuclear Information System (INIS)

    Takahashi, S.

    1983-01-01

    This book provides the following information: basic aspects of computed tomography; atlas of computed tomography of the normal adult; clinical application of computed tomography; and radiotherapy planning and computed tomography

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-03-01

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

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

    International Nuclear Information System (INIS)

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

    2002-01-01

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

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

    International Nuclear Information System (INIS)

    Murakami, Shogo

    2003-01-01

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

  9. Quantification of Global Left Ventricular Function: Comparison of Multidetector Computed Tomography and Magnetic Resonance Imaging. A Meta-analysis and Review of the Current Literature

    International Nuclear Information System (INIS)

    Vleuten, P.A. van der; Willems, T.P.; Goette, M.J.; Tio, R.A.; Greuter, M.J.; Zijlstra, F.; Oudkerk, M.

    2006-01-01

    Cardiac morbidity and mortality are closely related to cardiac volumes and global left ventricular (LV) function, expressed as left ventricular ejection fraction. Accurate assessment of these parameters is required for the prediction of prognosis in individual patients as well as in entire cohorts. The current standard of reference for left ventricular function is analysis by short-axis magnetic resonance imaging. In recent years, major extensive technological improvements have been achieved in computed tomography. The most marked development has been the introduction of the multidetector CT (MDCT), which has significantly improved temporal and spatial resolutions. In order to assess the current status of MDCT for analysis of LV function, the current available literature on this subject was reviewed. The data presented in this review indicate that the global left ventricular functional parameters measured by contemporary multi-detector row systems combined with adequate reconstruction algorithms and post-processing tools show a narrow diagnostic window and are interchangeable with those obtained by MRI

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  11. Quantification of ventilation distribution in regional lung injury by electrical impedance tomography and xenon computed tomography

    International Nuclear Information System (INIS)

    Elke, Gunnar; Weiler, Norbert; Frerichs, Inéz; Fuld, Matthew K; Halaweish, Ahmed F; Hoffman, Eric A; Grychtol, Bartłomiej

    2013-01-01

    Validation studies of electrical impedance tomography (EIT) based assessment of regional ventilation under pathological conditions are required to prove that EIT can reliably quantify heterogeneous ventilation distribution with sufficient accuracy. The objective of our study was to validate EIT measurements of regional ventilation through a comparison with xenon-multidetector-row computed tomography (XeCT) in an animal model of sub-lobar lung injury. Nine anesthetized mechanically ventilated supine pigs were examined before and after the induction of lung injury in two adjacent sub-lobar segments of the right lung by saline lavage or endotoxin instillation. Regional ventilation was determined in 32 anteroposterior regions of interest in the right and left lungs and the ventilation change quantified by difference images between injury and control. Six animals were included in the final analysis. Measurements of regional ventilation by EIT and XeCT correlated well before (r s = 0.89 right, r s = 0.90 left lung) and after local injury (r s = 0.79 and 0.92, respectively). No bias and narrow limits of agreement were found during both conditions. The ventilation decrease in the right injured lung was correspondingly measured by both modalities (5.5%±1.1% by EIT and 5.4%±1.9% by XeCT, p = 0.94). EIT was inferior to clearly separate the exact anatomical location of the regional injuries. Regional ventilation was overestimated (<2%) in the most ventral and dorsal regions and underestimated (2%) in the middle regions by EIT compared to XeCT. This study shows that EIT is able to reliably discern even small ventilation changes on sub-lobar level. (paper)

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  14. [Comparison of radiation dose reduction of prospective ECG-gated one beat scan using 320 area detector CT coronary angiography and prospective ECG-gated helical scan with high helical pitch (FlashScan) using 64 multidetector-row CT coronary angiography].

    Science.gov (United States)

    Matsutani, Hideyuki; Sano, Tomonari; Kondo, Takeshi; Fujimoto, Shinichiro; Sekine, Takako; Arai, Takehiro; Morita, Hitomi; Takase, Shinichi

    2010-12-20

    A high radiation dose associated with 64 multidetector-row computed tomography (64-MDCT) is a major concern for physicians and patients alike. A new 320 row area detector computed tomography (ADCT) can obtain a view of the entire heart with one rotation (0.35 s) without requiring the helical method. As such, ADCT is expected to reduce the radiation dose. We studied image quality and radiation dose of ADCT compared to that of 64-MDCT in patients with a low heart rate (HR≤60). Three hundred eighty-five consecutive patients underwent 64-MDCT and 379 patients, ADCT. Patients with an arrhythmia were excluded. Prospective ECG-gated helical scan with high HP (FlashScan) in 64 was used for MDCT and prospective ECG-gated conventional one beat scan, for 320-ADCT. Image quality was visually evaluated by an image quality score. Radiation dose was estimated by DLP (mGy・cm) for 64-MDCT and DLP.e (mGy・cm) for 320-ADCT. Radiation dose of 320-ADCT (208±48 mGy・cm) was significantly (P<0.0001) lower than that of 64-MDCT (484±112 mGy・cm), and image quality score of 320-ADCT (3.0±0.2) was significantly (P=0.0011) higher than that of 64-MDCT (2.9±0.4). Scan time of 320-ADCT (1.4±0.1 s) was also significantly (P<0.0001) shorter than that of 64-MDCT (6.8±0.6 s). 320-ADCT can achieve not only a reduction in radiation dose but also a superior image quality and shortening of scan time compared to 64-MDCT.

  15. 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 ... Safety Images related to Computed Tomography (CT) - Head Videos related to Computed Tomography (CT) - Head Sponsored by ...

  16. What is Computed Tomography?

    Science.gov (United States)

    ... Imaging Medical X-ray Imaging What is Computed Tomography? Share Tweet Linkedin Pin it More sharing options ... Chest X ray Image back to top Computed Tomography (CT) Although also based on the variable absorption ...

  17. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Stroke Brain Tumors Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  18. Computed tomography

    International Nuclear Information System (INIS)

    Boyd, D.P.

    1989-01-01

    This paper reports on computed tomographic (CT) scanning which has improved computer-assisted imaging modalities for radiologic diagnosis. The advantage of this modality is its ability to image thin cross-sectional planes of the body, thus uncovering density information in three dimensions without tissue superposition problems. Because this enables vastly superior imaging of soft tissues in the brain and body, CT scanning was immediately successful and continues to grow in importance as improvements are made in speed, resolution, and cost efficiency. CT scanners are used for general purposes, and the more advanced machines are generally preferred in large hospitals, where volume and variety of usage justifies the cost. For imaging in the abdomen, a scanner with a rapid speed is preferred because peristalsis, involuntary motion of the diaphram, and even cardiac motion are present and can significantly degrade image quality. When contrast media is used in imaging to demonstrate scanner, immediate review of images, and multiformat hardcopy production. A second console is reserved for the radiologist to read images and perform the several types of image analysis that are available. Since CT images contain quantitative information in terms of density values and contours of organs, quantitation of volumes, areas, and masses is possible. This is accomplished with region-of- interest methods, which involve the electronic outlining of the selected region of the television display monitor with a trackball-controlled cursor. In addition, various image- processing options, such as edge enhancement (for viewing fine details of edges) or smoothing filters (for enhancing the detectability of low-contrast lesions) are useful tools

  19. Computed Tomography (CT) -- Head

    Medline Plus

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

  20. Emission computed tomography

    International Nuclear Information System (INIS)

    Ott, R.J.

    1986-01-01

    Emission Computed Tomography is a technique used for producing single or multiple cross-sectional images of the distribution of radionuclide labelled agents in vivo. The techniques of Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) are described with particular regard to the function of the detectors used to produce images and the computer techniques used to build up images. (UK)

  1. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography (CT) of the sinuses uses special x-ray equipment ... story here Images × Image Gallery Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content ...

  2. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special x-ray equipment ... story here Images × Image Gallery Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content ...

  3. Optimization of coronary attenuation in coronary computed tomography angiography using diluted contrast material.

    Science.gov (United States)

    Kawaguchi, Naoto; Kurata, Akira; Kido, Teruhito; Nishiyama, Yoshiko; Kido, Tomoyuki; Miyagawa, Masao; Ogimoto, Akiyoshi; Mochizuki, Teruhito

    2014-01-01

    The purpose of this study was to evaluate a personalized protocol with diluted contrast material (CM) for coronary computed tomography angiography (CTA). One hundred patients with suspected coronary artery disease underwent retrospective electrocardiogram-gated coronary CTA on a 256-slice multidetector-row CT scanner. In the diluted CM protocol (n=50), the optimal scan timing and CM dilution rate were determined by the timing bolus scan, with 20% CM dilution (5ml/s during 10s) being considered suitable to achieve the target arterial attenuation of 350 Hounsfield units (HU). In the body weight (BW)-adjusted protocol (n=50, 222mg iodine/kg), only the optimal scan timing was determined by the timing bolus scan. The injection rate and volume in the timing bolus scan and real scan were identical between the 2 protocols. We compared the means and variations in coronary attenuation between the 2 protocols. Coronary attenuation (mean±SD) in the diluted CM and BW-adjusted protocols was 346.1±23.9 HU and 298.8±45.2 HU, respectively. The diluted CM protocol provided significantly higher coronary attenuation and lower variance than did the BW-adjusted protocol (P<0.05, in each). The diluted CM protocol facilitates more uniform attenuation on coronary CTA in comparison with the BW-adjusted protocol.  

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-10-15

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

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

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

    International Nuclear Information System (INIS)

    Tan, Xiaotian

    2002-01-01

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

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-15

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  10. Computed tomography for radiographers

    International Nuclear Information System (INIS)

    Brooker, M.

    1986-01-01

    Computed tomography is regarded by many as a complicated union of sophisticated x-ray equipment and computer technology. This book overcomes these complexities. The rigid technicalities of the machinery and the clinical aspects of computed tomography are discussed including the preparation of patients, both physically and mentally, for scanning. Furthermore, the author also explains how to set up and run a computed tomography department, including advice on how the room should be designed

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-09-15

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

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  15. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... are the limitations of CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed ... nasal cavity by small openings. top of page What are some common uses of the procedure? CT ...

  16. Emission computed tomography

    International Nuclear Information System (INIS)

    Budinger, T.F.; Gullberg, G.T.; Huesman, R.H.

    1979-01-01

    This chapter is devoted to the methods of computer assisted tomography for determination of the three-dimensional distribution of gamma-emitting radionuclides in the human body. The major applications of emission computed tomography are in biological research and medical diagnostic procedures. The objectives of these procedures are to make quantitative measurements of in vivo biochemical and hemodynamic functions

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

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    Full Text Available ... Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is a fast, painless exam that uses special ... the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known as a CT or CAT ...

  18. 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 ...

  19. Radiation doses to patients receiving computed tomography examinations in British Columbia

    International Nuclear Information System (INIS)

    Aldrich, J.E.; Bilawich, A.-M.; Mayo, J.R.

    2006-01-01

    To estimate the diagnostic reference levels and effective radiation dose to patients from routine computed tomography (CT) examinations in the province of British Columbia, Canada. The patient weight, height and computed tomography dose index or dose linear product (DLP) were recorded on study sheets for 1070 patients who were referred for clinically indicated routine CT examinations at 18 radiology departments in British Columbia. Sixteen of the scanners were multidetector row scanners. The average patient dose varied from hospital to hospital. The largest range was found for CT of the abdomen, for which the dose varied from 3.6 to 26.5 (average 10.1) mSv. For head CT, the range was 1.7 to 4.9 (average 2.8) mSv; for chest CT, it was 3.8 to 26 (average 9.3) mSv; for pelvis CT, it was 3.5 to 15.5 (average 9.0) mSv; and for abdomen/pelvis CT, it was 7.3 to 31.5 (average 16.3) mSv. Reference dose values were calculated for each exam. These DLP values are as follows: head, 1300 mGy cm; chest, 600 mGy cm; abdomen, 920 mGy cm; pelvis, 650 mGy cm; and abdomen/pelvis, 1100 mGy cm. Among hospitals, there was considerable variation in the DLP and patient radiation dose for a specific exam. Reference doses and patient doses were higher than those found in similar recent surveys carried out in the United Kingdom and the European Union. Patient doses were similar to those found in a recent survey in Germany. (author)

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  1. Computer tomography in otolaryngology

    International Nuclear Information System (INIS)

    Gradzki, J.

    1981-01-01

    The principles of design and the action of computer tomography which was applied also for the diagnosis of nose, ear and throat diseases are discussed. Computer tomography makes possible visualization of the structures of the nose, nasal sinuses and facial skeleton in transverse and eoronal planes. The method enables an accurate evaluation of the position and size of neoplasms in these regions and differentiation of inflammatory exudates against malignant masses. In otology computer tomography is used particularly in the diagnosis of pontocerebellar angle tumours and otogenic brain abscesses. Computer tomography of the larynx and pharynx provides new diagnostic data owing to the possibility of obtaining transverse sections and visualization of cartilage. Computer tomograms of some cases are presented. (author)

  2. Computed Tomography (CT) -- Head

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    Full Text Available ... for Brain Tumors Radiation Therapy for Head and Neck Cancer Others American Stroke Association National Stroke Association ... Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine ...

  3. Computed Tomography (CT) -- Head

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    Full Text Available ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  4. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  5. Computed Tomography (CT) -- Head

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    Full Text Available ... the limitations of CT Scanning of the Head? What is CT Scanning of the Head? Computed tomography, ... than regular radiographs (x-rays). top of page What are some common uses of the procedure? CT ...

  6. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... of the Head? Computed tomography, more commonly known as a CT or CAT scan, is a diagnostic ... white on the x-ray; soft tissue, such as organs like the heart or liver, shows up ...

  7. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... of the Sinuses? Computed tomography, more commonly known as a CT or CAT scan, is a diagnostic ... white on the x-ray; soft tissue, such as organs like the heart or liver, shows up ...

  8. Computed Tomography (CT) -- Head

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info About Us News Physician Resources Professions Site Index A-Z Computed Tomography ( ...

  9. Computed Tomography (CT) -- Sinuses

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info About Us News Physician Resources Professions Site Index A-Z Computed Tomography ( ...

  10. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... Computed tomography (CT) of the sinuses uses special x-ray equipment to evaluate the paranasal sinus cavities – hollow, air-filled spaces within the bones of the face surrounding the ...

  11. Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

    International Nuclear Information System (INIS)

    Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E.; El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria; Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke; Kroft, Lucia J.; Younis, Imad Al; Reiber, Johan H.; Scholte, Arthur J.

    2013-01-01

    Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 ± 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS ≥2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p 2 = 20.7) and lesion length (χ 2 = 26.0) to the clinical variables and the visual assessment (χ 2 = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have incremental value over baseline variables and visually assessed significant stenosis. Potentially, QCT can refine assessment of CAD, which may be of potential use for identification of patients with myocardial ischaemia. (orig.)

  12. Multidetector computed tomography predictors of late ventricular remodeling and function after acute myocardial infarction

    International Nuclear Information System (INIS)

    Lessick, Jonathan; Abadi, Sobhi; Agmon, Yoram; Keidar, Zohar; Carasso, Shemi; Aronson, Doron; Ghersin, Eduard; Rispler, Shmuel; Sebbag, Anat; Israel, Ora; Hammerman, Haim; Roguin, Ariel

    2012-01-01

    Background: Despite advent of rapid arterial revascularization as 1st line treatment for acute myocardial infarction (AMI), incomplete restoral of flow at the microvascular level remains a problem and is associated with adverse prognosis, including pathological ventricular remodeling. We aimed to study the association between multidetector row computed tomography (MDCT) perfusion defects and ventricular remodeling post-AMI. Methods: In a prospective study, 20 patients with ST-elevation AMI, treated by primary angioplasty, underwent arterial and late phase MDCT as well as radionuclide scans to study presence, size and severity of myocardial perfusion defects. Contrast echocardiography was performed at baseline and at 4 months follow-up to evaluate changes in myocardial function and remodeling. Results: Early defects (ED), late defects (LD) and late enhancement (LE) were detected in 15, 7 and 16 patients, respectively and radionuclide defects in 15 patients. The ED area (r = 0.74), and LD area (r = 0.72), and to a lesser extent LE area (r = 0.62) correlated moderately well with SPECT summed rest score. By univariate analysis, follow-up end-systolic volume index and ejection fraction were both significantly related to ED and LD size and severity, but not to LE size or severity. By multivariate analysis, end-systolic volume index was best predicted by LD area (p < 0.05) and ejection fraction by LD enhancement ratio. Conclusions: LD size and severity on MDCT are most closely associated with pathological ventricular remodeling after AMI and may thus play a role in early identification and treatment of this condition

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

    International Nuclear Information System (INIS)

    Osada, Hisato; Watanabe, Wataru; Okada, Taketomo

    2007-01-01

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

  14. Computed Tomography (CT) -- Head

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head ...

  15. Computed Tomography (CT) -- Sinuses

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses ...

  16. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Share your patient story here Images × Image Gallery Patient undergoing computed 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. Related ...

  17. Computed Tomography (CT) -- Head

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    Full Text Available ... Share your patient story here Images × Image Gallery Patient undergoing computed 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. Related ...

  18. Computed tomography in traumatology

    International Nuclear Information System (INIS)

    Heller, M.; Jend, H.H.

    1986-01-01

    This volume offers a critical review and assessment of new avenues opened up by computed tomography in traumatology. Over 200 illustrations, including numerous CT scans, aid the physician engaged emergency care and postoperative treatment of accident victims. Technical prerequisites, special techniques of investigation, pathomorphology of organ changes conditioned by trauma, diagnostic leading symptoms and signs, and diagnostics of iatrogenic injuries and lesions are presented

  19. Computed tomography system

    International Nuclear Information System (INIS)

    Lambert, T.W.; Blake, J.E.

    1981-01-01

    This invention relates to computed tomography and is particularly concerned with determining the CT numbers of zones of interest in an image displayed on a cathode ray tube which zones lie in the so-called level or center of the gray scale window. (author)

  20. Chest computed tomography

    DEFF Research Database (Denmark)

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

    2013-01-01

    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...

  1. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Computed tomography (CT) of the head uses special x-ray equipment to help assess head injuries, severe headaches, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  2. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Computed tomography (CT) of the sinuses uses special x-ray equipment to evaluate the paranasal sinus cavities – hollow, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  3. Computed tomography for radiographers

    International Nuclear Information System (INIS)

    Brooker, M.J.

    1986-01-01

    This book is directed towards giving radiographers an introduction to and basic knowledge of computerized tomography. The technical section discusses gantries and x-ray production, computer and disc drive image display, storage, artefacts quality assurance and design of departments. The clinical section includes patient preparation, radiotherapy planning, and interpretation of images from various areas of the anatomy. (U.K.)

  4. Quantitative cardiac computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Thelen, M.; Dueber, C.; Wolff, P.; Erbel, R.; Hoffmann, T.

    1985-06-01

    The scope and limitations of quantitative cardiac CT have been evaluated in a series of experimental and clinical studies. The left ventricular muscle mass was estimated by computed tomography in 19 dogs (using volumetric methods, measurements in two axes and planes and reference volume). There was good correlation with anatomical findings. The enddiastolic volume of the left ventricle was estimated in 22 patients with cardiomyopathies; using angiography as a reference, CT led to systematic under-estimation. It is also shown that ECG-triggered magnetic resonance tomography results in improved visualisation and may be expected to improve measurements of cardiac morphology.

  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. Computed tomographic characteristics of collateral venous pathways in dogs with caudal vena cava obstruction.

    Science.gov (United States)

    Specchi, Swan; d'Anjou, Marc-André; Carmel, Eric Norman; Bertolini, Giovanna

    2014-01-01

    Collateral venous pathways develop in dogs with obstruction or increased blood flow resistance at any level of the caudal vena cava in order to maintain venous drainage to the right atrium. The purpose of this retrospective study was to describe the sites, causes of obstruction, and configurations of venous collateral pathways for a group of dogs with caudal vena cava obstruction. Computed tomography databases from two veterinary hospitals were searched for dogs with a diagnosis of caudal vena cava obstruction and multidetector row computed tomographic angiographic (CTA) scans that included the entire caudal vena cava. Images for each included dog were retrieved and collateral venous pathways were characterized using image postprocessing and a classification system previously reported for humans. A total of nine dogs met inclusion criteria and four major collateral venous pathways were identified: deep (n = 2), portal (n = 2), intermediate (n = 7), and superficial (n = 5). More than one collateral venous pathway was present in 5 dogs. An alternative pathway consisting of renal subcapsular collateral veins, arising mainly from the caudal pole of both kidneys, was found in three dogs. In conclusion, findings indicated that collateral venous pathway patterns similar to those described in humans are also present in dogs with caudal vena cava obstruction. These collateral pathways need to be distinguished from other vascular anomalies in dogs. Postprocessing of multidetector-row CTA images allowed delineation of the course of these complicated venous pathways and may be a helpful adjunct for treatment planning in future cases. © 2014 American College of Veterinary Radiology.

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

    Medline Plus

    Full Text Available ... Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is a fast, painless exam that uses ... of Children's CT? What is Children's CT? Computed tomography, more commonly known as a CT or CAT ...

  8. Computed Tomography. Chapter 11

    Energy Technology Data Exchange (ETDEWEB)

    Geleijns, J. [Leiden University Medical Centre, Leiden (Netherlands)

    2014-09-15

    After its clinical introduction in 1971, computed tomography (CT) developed from an X ray modality that was limited to axial imaging of the brain in neuroradiology into a versatile 3-D whole body imaging modality for a wide range of applications, including oncology, vascular radiology, cardiology, traumatology and interventional radiology. CT is applied for diagnosis and follow-up studies of patients, for planning of radiotherapy, and even for screening of healthy subpopulations with specific risk factors.

  9. Computed Tomography Status

    Science.gov (United States)

    Hansche, B. D.

    1983-01-01

    Computed tomography (CT) is a relatively new radiographic technique which has become widely used in the medical field, where it is better known as computerized axial tomographic (CAT) scanning. This technique is also being adopted by the industrial radiographic community, although the greater range of densities, variation in samples sizes, plus possible requirement for finer resolution make it difficult to duplicate the excellent results that the medical scanners have achieved.

  10. Mathematics of Computed Tomography

    Science.gov (United States)

    Hawkins, William Grant

    A review of the applications of the Radon transform is presented, with emphasis on emission computed tomography and transmission computed tomography. The theory of the 2D and 3D Radon transforms, and the effects of attenuation for emission computed tomography are presented. The algebraic iterative methods, their importance and limitations are reviewed. Analytic solutions of the 2D problem the convolution and frequency filtering methods based on linear shift invariant theory, and the solution of the circular harmonic decomposition by integral transform theory--are reviewed. The relation between the invisible kernels, the inverse circular harmonic transform, and the consistency conditions are demonstrated. The discussion and review are extended to the 3D problem-convolution, frequency filtering, spherical harmonic transform solutions, and consistency conditions. The Cormack algorithm based on reconstruction with Zernike polynomials is reviewed. An analogous algorithm and set of reconstruction polynomials is developed for the spherical harmonic transform. The relations between the consistency conditions, boundary conditions and orthogonal basis functions for the 2D projection harmonics are delineated and extended to the 3D case. The equivalence of the inverse circular harmonic transform, the inverse Radon transform, and the inverse Cormack transform is presented. The use of the number of nodes of a projection harmonic as a filter is discussed. Numerical methods for the efficient implementation of angular harmonic algorithms based on orthogonal functions and stable recursion are presented. The derivation of a lower bound for the signal-to-noise ratio of the Cormack algorithm is derived.

  11. Loss of cellular viability in areas of ground-glass opacity on computed tomography images immediately after pulmonary radiofrequency ablation in rabbits

    International Nuclear Information System (INIS)

    Kuroki, Masaomi; Nakada, Hiroshi; Yamashita, Atsushi; Sawaguchi, Akira; Uchino, Noriko; Sato, Shinya; Asada, Yujiro; Tamura, Shozo; Asanuma, Taketoshi

    2012-01-01

    The purpose of this study was to determine cellular viability of lung parenchyma and neoplastic cells in areas of ground-glass opacity (GGO) on computed tomography (CT) images immediately after pulmonary radiofrequency ablation (RFA) in rabbits. A LeVeen RFA electrode was placed percutaneously into rabbit lungs with or without metastatic VX2 tumors. Five minutes later, seven isolated lungs were imaged by use of a multi-detector row CT scanner, and the images were compared with histological features. The cellular viability of the lung tissues was assessed by nicotinamide adenine dinucleotide hydrogen (NADH) staining in eight normal lungs and in three lungs with multiple metastatic tumors. All lung lesions appeared as bilayered structures with a central, dense, attenuated area and an outer area of GGO on CT images, and as three-layered structures on macroscopic and microscopic images 5 min after RFA. The GGO areas approximately corresponded to the outer two layers in macroscopic images that were exudative and congestive on microscopic images. Staining for NADH was significantly reduced in the GGO and densely attenuated areas with or without tumor tissue staining compared with the non-ablated area. Our results suggest that an area of GGO that appears on CT immediately after RFA can be effectively treated by RFA. (author)

  12. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Kelman, A.L.; Peterson, T.E.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. The tracks are supported on rollers which carry the substantial weight. Explicit engineering details are presented especially of the ball bearing races used in the rotation. (U.K.)

  13. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Brandt, R.T.; Hein, P.W.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. The tracks are supported on rollers which carry the substantial weight. Explicit engineering details are presented. (U.K.)

  14. Multislice computed tomography coronary angiography

    NARCIS (Netherlands)

    F. Cademartiri (Filippo)

    2005-01-01

    markdownabstract__Abstract__ Computed Tomography (CT) imaging is also known as "CAT scanning" (Computed Axial Tomography). Tomography is from the Greek word "tomos" meaning "slice" or "section" and "graphia" meaning "describing". CT was invented in 1972 by British engineer Godfrey Hounsfield

  15. Coronary artery anomalies: Assessment with electrocardiography-gate multidetector-row CT at a single center in Korea

    International Nuclear Information System (INIS)

    Yi, Bo Ram; Sun, Joo Sung; Yang, Hyoung Mo; Kang, Doo Kyoung

    2015-01-01

    To determine the prevalence of coronary anomalies using coronary computed tomography angiography (CCTA) and to evaluate the relationship between coronary artery anomalies and chest pain. A total of 12676 patients underwent CCTA scans at our institution between December 2006 and April 2013 using a 64-slice CT and a 128-slice dual-source CT. We determined the prevalence of coronary artery anomalies according to the classification system proposed by Greenberg. The presence or absence of chest pain with each coronary artery anomaly was also evaluated. Coronary anomalies were found in 176 patients (1.39%) at our institute. Anomalies of origination, course, and termination were detected in 118 (0.93%), 28 (0.22%), and 30 (0.24%) patients, respectively. After the exclusion of 32 patients with combined heart disease, typical (n = 16; 11.1%) or atypical (n = 28; 19.4%) chest pain was present in 44 (30.6%) of the 144 patients at the time of diagnosis. The prevalence of coronary artery anomalies was 1.39% at our hospital. After the exclusion of patients with combined heart disease, 11.1% had typical chest pain at the time of diagnosis.

  16. Computed tomography device

    International Nuclear Information System (INIS)

    Ohhashi, A.

    1985-01-01

    A computed tomography device comprising a subtraction unit which obtains differential data strings representing the difference between each time-serial projection data string of a group of projection data strings corresponding to a prospective reconstruction image generated by projection data strings acquired by a data acquisition system, a convolution unit which convolves each time-serial projection data string of the group of projection data strings corresponding to the prospective reconstruction image, and a back-projection unit which back-projects the convolved data strings

  17. Method for computed tomography

    International Nuclear Information System (INIS)

    Wagner, W.

    1980-01-01

    In transversal computer tomography apparatus, in which the positioning zone in which the patient can be positioned is larger than the scanning zone in which a body slice can be scanned, reconstruction errors are liable to occur. These errors are caused by incomplete irradiation of the body during examination. They become manifest not only as an incorrect image of the area not irradiated, but also have an adverse effect on the image of the other, completely irradiated areas. The invention enables reduction of these errors

  18. Dosimetry in computed tomography

    International Nuclear Information System (INIS)

    Andisco, D.; Blanco, S.; Buzzia, A.E.

    2014-01-01

    Objective: The amount of computed tomography (CT) studies that are performed each year in the world is growing exponentially mainly due to the incorporation of multislice CT that allows studies in a few seconds. But, despite the benefit received by patients with the diagnosis, radiation dose is a concern in the professional community and it has be reduced as much as reasonably possible. This article describes the main dosimetric CT units used in order to work with this practice easily, using the values that provide modern equipment and internationally known reference levels. (authors) [es

  19. Mesenteric panniculitis: computed tomography aspects

    International Nuclear Information System (INIS)

    Moreira, Luiza Beatriz Melo; Alves, Jose Ricardo Duarte; Marchiori, Edson; Pinheiro, Ricardo Andrade; Melo, Alessandro Severo Alves de; Noro, Fabio

    2001-01-01

    Mesenteric panniculitis is an inflammatory process that represents the second stage of a rare progressive disease involving the adipose tissue of the mesentery. Imaging methods used in the diagnosis of mesenteric panniculitis include barium studies, ultrasonography, computed tomography and magnetic resonance imaging. Computed tomography is important for both, diagnosis and evaluation of the extension of the disease and treatment monitoring. Computed tomography findings may vary according to the stage of the disease and the amount of inflammatory material or fibrosis. There is also good correlation between the computed tomography and anatomical pathology findings. The authors studied 10 patients with mesenteric panniculitis submitted to computed tomography. Magnetic resonance imaging was also performed in one patient. In all patients, computed tomography revealed a heterogeneous mass in the mesentery with density of fat, interspersed with areas of soft tissue density and dilated vessels. (author)

  20. The neutron computer tomography

    International Nuclear Information System (INIS)

    Matsumoto, G.; Krata, S.

    1983-01-01

    The method of computer tomography (CT) was applied for neutrons instead of X-rays. The neutron radiography image of samples was scanned by microphotometer to get the transmission data. This process was so time-consuming that the number of incident angles to samples could not be increased. The transmission data was processed by FACOM computer and CT image was gained. In the experiment at the Japan Research Reactor No. 4 at Tokai-mura with 18 projection angles, the resolution of paraffin in the aluminum block was less than 0.8 mm. In the experiment at Van de Graaf accelerator of Nagoya University, this same resolution was 1.2 mm because of the angle distribution of neutron beam. This experiment is the preliminary one, the facility which utilizes neutron television and video-recorder will be necessary for the next stage. (Auth.)

  1. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Kelman, A.L.; O'Dell, W.R.; Brook, R.F.; Hein, P.W.; Brandt, R.T.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. A failsafe, solenoid brake is described which can lock the shaft against rotation. The gantry also contains a hoist mechanism which aids maintenance of the heavy X-ray tube and/or detector arrays. Explicit engineering details are presented. (U.K.)

  2. Detection of intestinal bleeding with multi-detector row CT in an experimental setup. How many acquisitions are necessary?

    International Nuclear Information System (INIS)

    Dobritz, Martin; Engels, Heinz-Peter; Bauer, Jan; Rummeny, Ernst J.; Schneider, Armin

    2009-01-01

    The purpose of the study was to evaluate multi-detector computed tomography (MDCT) acquired in different acquisitions (unenhanced, and arterial and portal venous phase following intravenous contrast medium) for detection of intestinal bleeding using an experimental bowel model. The model consisted of an injector tube with a perforation placed in a 7-m-long small bowel of a pig. The bowel was filled with water/contrast medium solution of 30-40 HU and was incorporated in a phantom model. Intestinal bleeding in different locations and bleeding velocities varying from zero to 0.75 ml/min (0.05 ml/min increments) were simulated. Twenty-six datasets in simulated unenhanced, arterial and portal venous contrast phase using increasing bleeding velocities and ten negative controls were measured using 64-row MDCT. Two radiologists blinded to the experimental settings evaluated the datasets in a random order. The likelihood of intestinal bleeding was assessed using a 5-point scale with subsequent ROC analysis. The overall sensitivity for detecting bleeding was 0.44 for an arterial acquisition alone, 0.68 for a portal venous acquisition, 0.68 for the combination unenhanced/arterial, 0.72 for unenhanced/portal venous and 0.80 for arterial/portal. Bleeding velocities of above 0.25 ml/min were detected with a sensitivity of 0.59 for arterial, 0.88 for portal venous, 0.85 for unenhanced/arterial, 0.94 for unenhanced/portal venous and 0.97 for arterial/portal venous contrast phase protocols, respectively. The specificity was 1.00. MDCT provides the highest sensitivity and specificity in the detection of intestinal bleeding using arterial and portal venous acquisition in comparison to mono-phase protocols. (orig.)

  3. Impaired left ventricular function has a detrimental effect on image quality in multi-detector row CT coronary angiography

    International Nuclear Information System (INIS)

    Manghat, N.E.; Morgan-Hughes, G.J.; Shaw, S.R.; Marshall, A.J.; Roobottom, C.A.

    2008-01-01

    Aim: To determine whether there is a relationship between left ventricular (LV) haemodynamic parameters, circulation times, and arterial contrast opacification that might affect the image quality of computed tomography (CT) coronary angiography. Methods: Thirty-six patients were included in the study: 18 with cardiomyopathy (CM) and LV dilatation of suspected ischaemic aetiology [age 57.9 ± 13.7 years, range 30-77 years; 14 male, four female; body mass index (BMI) = 27.7 ± 4.5, range 25.5-31.8] and 18 controls (age 62.3 ± 9.4 years, range 47-89 years; 10 male, eight female; BMI 27.8 ± 6.6; range 19.2-33.6). Coronary artery image quality was assessed using a three-point visual scale; contrast medium circulation times, aortic root contrast attenuation, and LV functional parameters were studied. Results: Visually reduced contrast opacification impaired image quality more often in the CM group than the control group (27.4 versus 5.1%). A total of 55.6% CM patients had a contrast transit time ranging from 30-75 s; the number of 'unassessable' segments increased with increasing transit time conforming to a fitted quadratic model (R 2 = 0.74). The relationship between LV ejection fraction and contrast attenuation may also conform to a quadratic model (R 2 = 0.71). Conclusion: LV haemodynamics influence coronary artery opacification using cardiac CT, and users imaging this subgroup must do so with the knowledge of this potential pitfall. The results indicate the need for further studies examining CT protocols in this clinical subgroup

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

    International Nuclear Information System (INIS)

    Sumikawa, Hiromitsu; Johkoh, Takeshi; Koyama, Mitsuhiro

    2005-01-01

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

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

    International Nuclear Information System (INIS)

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

    2003-01-01

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

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

    Science.gov (United States)

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

    2012-10-01

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

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  9. Computed tomography in facial trauma

    International Nuclear Information System (INIS)

    Zilkha, A.

    1982-01-01

    Computed tomography (CT), plain radiography, and conventional tomography were performed on 30 patients with facial trauma. CT demonstrated bone and soft-tissue involvement. In all cases, CT was superior to tomography in the assessment of facial injury. It is suggested that CT follow plain radiography in the evaluation of facial trauma

  10. Proton computed tomography

    International Nuclear Information System (INIS)

    Hanson, K.M.

    1978-01-01

    The use of protons or other heavy charged particles instead of x rays in computed tomography (CT) is explored. The results of an experimental implementation of proton CT are presented. High quality CT reconstructions are obtained at an average dose reduction factor compared with an EMI 5005 x-ray scanner of 10:1 for a 30-cm-diameter phantom and 3.5:1 for a 20-cm diameter. The spatial resolution is limited by multiple Coulomb scattering to about 3.7 mm FWHM. Further studies are planned in which proton and x-ray images of fresh human specimens will be compared. Design considerations indicate that a clinically useful proton CT scanner is eminently feasible

  11. Positron emission computed tomography

    International Nuclear Information System (INIS)

    Grover, M.; Schelbert, H.R.

    1985-01-01

    Regional mycardial blood flow and substrate metabolism can be non-invasively evaluated and quantified with positron emission computed tomography (Positron-CT). Tracers of exogenous glucose utilization and fatty acid metabolism are available and have been extensively tested. Specific tracer kinetic models have been developed or are being tested so that glucose and fatty acid metabolism can be measured quantitatively by Positron-CT. Tracers of amino acid and oxygen metabolism are utilized in Positron-CT studies of the brain and development of such tracers for cardiac studies are in progress. Methods to quantify regional myocardial blood flow are also being developed. Previous studies have demonstrated the ability of Positron-/CT to document myocardial infarction. Experimental and clinical studies have begun to identify metabolic markers of reversibly ischemic myocardium. The potential of Positron-CT to reliably detect potentially salvageable myocardium and, hence, to identify appropriate therapeutic interventions is one of the most exciting applications of the technique

  12. Computer tomography of the neurocranium.

    Science.gov (United States)

    Liliequist, B; Forssell, A

    1976-07-01

    The experience with computer tomography of the neurocranium in 300 patients submitted for computer tomography of the brain is reported. The more appropriate projections which may be obtained with the second generation of scanners in combination with an elaborated reconstruction technique seem to constitute a replacement of conventional skull films.

  13. Reduction of thoracic aorta motion artifact with high-pitch 128-slice dual-source computed tomographic angiography: a historical control study.

    Science.gov (United States)

    Nakagawa, Junichiro; Tasaki, Osamu; Watanabe, Yoshiyuki; Azuma, Takeo; Ohnishi, Mitsuo; Ukai, Isao; Tahara, Kenichi; Ogura, Hiroshi; Kuwagata, Yasuyuki; Hamasaki, Toshimitsu; Shimazu, Takeshi

    2013-01-01

    Electrocardiogram-gated imaging combined with multi-detector row computed tomography (MDCT) has reduced cardiac motion artifacts, but it was not practical in the emergency setting. The purpose of this study was to evaluate the ability of a high-pitch, 128-slice dual-source CT (DSCT) scanner to reduce motion artifacts in patients admitted to the emergency room. This study comprised 100 patients suspected of having thoracic aorta lesions. We examined 47 patients with the 128-slice DSCT scanner (DSCT group), and 53 patients were examined with a 64-slice MDCT scanner (MDCT group). Six anatomic areas in the thoracic aorta were evaluated. Computed tomography images in the DSCT group were distinct, and significant differences were observed in images of all areas between the 2 groups except for the descending aorta. The high-pitch DSCT scanner can reduce motion artifacts of the thoracic aorta and enable radiological diagnosis even in patients with tachycardia and without breath hold.

  14. Volume-rendered hemorrhage-responsible arteriogram created by 64 multidetector-row CT during aortography: utility for catheterization in transcatheter arterial embolization for acute arterial bleeding.

    Science.gov (United States)

    Minamiguchi, Hiroki; Kawai, Nobuyuki; Sato, Morio; Ikoma, Akira; Sanda, Hiroki; Nakata, Kouhei; Tanaka, Fumihiro; Nakai, Motoki; Sonomura, Tetsuo; Murotani, Kazuhiro; Hosokawa, Seiki; Nishioku, Tadayoshi

    2014-01-01

    Aortography for detecting hemorrhage is limited when determining the catheter treatment strategy because the artery responsible for hemorrhage commonly overlaps organs and non-responsible arteries. Selective catheterization of untargeted arteries would result in repeated arteriography, large volumes of contrast medium, and extended time. A volume-rendered hemorrhage-responsible arteriogram created with 64 multidetector-row CT (64MDCT) during aortography (MDCTAo) can be used both for hemorrhage mapping and catheter navigation. The MDCTAo depicted hemorrhage in 61 of 71 cases of suspected acute arterial bleeding treated at our institute in the last 3 years. Complete hemostasis by embolization was achieved in all cases. The hemorrhage-responsible arteriogram was used for navigation during catheterization, thus assisting successful embolization. Hemorrhage was not visualized in the remaining 10 patients, of whom 6 had a pseudoaneurysm in a visceral artery; 1 with urinary bladder bleeding and 1 with chest wall hemorrhage had gaze tamponade; and 1 with urinary bladder hemorrhage and 1 with uterine hemorrhage had spastic arteries. Six patients with pseudoaneurysm underwent preventive embolization and the other 4 patients were managed by watchful observation. MDCTAo has the advantage of depicting the arteries responsible for hemoptysis, whether from the bronchial arteries or other systemic arteries, in a single scan. MDCTAo is particularly useful for identifying the source of acute arterial bleeding in the pancreatic arcade area, which is supplied by both the celiac and superior mesenteric arteries. In a case of pelvic hemorrhage, MDCTAo identified the responsible artery from among numerous overlapping visceral arteries that branched from the internal iliac arteries. In conclusion, a hemorrhage-responsible arteriogram created by 64MDCT immediately before catheterization is useful for deciding the catheter treatment strategy for acute arterial bleeding.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-05-15

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

  16. Acute pulmonary embolism: prediction of cor pulmonale and short-term patient survival from assessment of cardiac dimensions in routine multidetector-row CT

    International Nuclear Information System (INIS)

    Engeike, C.; Rummeny, E.; Marten, K.

    2006-01-01

    Purpose: evaluation of the prognostic value of morphological cardiac parameters in patients with suspected and incidental acute pulmonary embolism (PE) using multidetector-row chest CT (MSCT). Materials and methods: 2335 consecutive MSCT scans were evaluated for the presence of PE. The arterial enhancement and analysability of pulmonary arteries and the heart were assessed as parameters of the scan quality. The diastolic right and left ventricular short axes (RV D , LV D ) and the interventricular septal deviation (ISD) were measured in all PE-positive patients and the echocardiography reports were reviewed. The clinical data assessment included cardio-respiratory and other co-morbidities, systemic anticoagulant therapy (ACT), and the 30-day outcome. Predictors of acute cor pulmonale and the short-term outcome were calculated by univariate and multivariate logistic regressions including odds ratios (OR) and ROC analyses using positive (PPV) and negative predictive values (NPV). Results: 90 patients with acute PE were included (36 with clinically suspected PE, 54 with incidental PE). 26 patients had cardio-respiratory co-morbidities. Four patients underwent systemic thrombolysis, 43 underwent anticoagulation in therapeutic doses, 19 underwent anticoagulation in prophylactic doses, and 24 patients did not undergo ACT. 15 of 41 patients had echocardiographic evidence of acute cor pulmonale. 8 patients died within 30 days. The RV D was the best independent predictor of acute cor pulmonale (p = 0,002, OR = 9.16, PPV = 0.68, NPV=1 at 4.49 cm cut off) and short-term outcome (p= 0,0005, OR = 2.82, PPV = 0.23, NPV = 0.98 at 4.75 cm cut off). The RV D /LV D ratio had a PPV of 0.85 for cor pulmonale. (orig.)

  17. 64-Slice multidetector row CT angiography of the abdomen: comparison of low versus high concentration iodinated contrast media in a porcine model

    Science.gov (United States)

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

    2011-01-01

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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  20. Multi-detector row CT of the head and neck: comparison of different volumes of contrast material with and without a saline chaser

    International Nuclear Information System (INIS)

    Yoon, Dae Young; You, Su Yeon; Choi, Chul Soon; Chang, Suk Ki; Yun, Eun Joo; Seo, Young Lan; Park, Sang Joon; Lee, Yu-Jin; Moon, Jeung Hee; Rho, Young-Soo; Kim, Jin-Hwan

    2006-01-01

    The aim of this study was to determine the effect of different volumes of contrast material with and without a saline chaser on tissue enhancement in multidetector row CT (MDCT) of the head and neck. In a blind prospective fashion, 120 patients were randomized into the following four groups: group 1, 80 ml contrast material administered at a flow rate of 2.0 ml/s; group 2, 80 ml followed by 40 ml saline at 2.0 ml/s; group 3, 60 ml at 1.5 ml/s; and group 4, 60 ml followed by 30 ml saline at 1.5 ml/s. The attenuation values of the carotid artery, internal jugular vein, and muscle were measured at an interval of 1.5 s in each patient. The degree of perivenous artifacts was subjectively assessed. Mean attenuation values in the carotid artery and internal jugular vein were significantly higher in groups 1 and 2 than in groups 3 and 4. The width of the diagnostic window (both carotid and jugular enhancement >150 HU) were significantly longer in groups 1 and 2 than in groups 3 and 4. The addition of a saline chaser did not result in improved vascular enhancement or a wider diagnostic window, but reduced perivenous artifacts, compared with using contrast material alone. Reduction of contrast material from 80 to 60 ml results in insufficient enhancement of neck vessels. In addition, the benefit of a saline chaser technique is not obvious except for its ability to reduce perivenous artifacts. (orig.)

  1. Computed tomography apparatus

    International Nuclear Information System (INIS)

    Fairbairn, I.A.

    1984-01-01

    In fan-beam computed tomography apparatus, timing reference pulses, normally occurring at intervals t, for data transfer and reset of approx. 500 integrators in the signal path from the detector array, are generated from the scan displacement, e.g. using a graticule and optical sensor to relate the measurement paths geometrically to the body section. Sometimes, a slow scan rate is required to provide a time-averaged density image, e.g. for planning irradiation therapy, and then the sensed impulses will occur at extended intervals and can cause integrator overload. An improvement is described which provides a pulse generator which responds to a reduced scan rate by generating a succession of further transfer and reset pulses at intervals approximately equal to t starting a time t after each timing reference pulse. Then, using an adding device and RAM, all the transferred signals integrated in the interval t' between two successive slow scan reference pulses are accumulated in order to form a corresponding measurement signal. (author)

  2. Computed tomography intravenous cholangiography

    International Nuclear Information System (INIS)

    Nascimento, S.; Murray, W.; Wilson, P.

    1997-01-01

    Indications for direct visualization of the bile ducts include bile duct dilatation demonstrated by ultrasound or computed tomography (CT) scanning, where the cause of the bile duct dilatation is uncertain or where the anatomy of bile duct obstruction needs further clarification. Another indication is right upper quadrant pain, particularly in a post-cholecystectomy patient, where choledocholithiasis is suspected. A possible new indication is pre-operative evaluation prior to laparoscopic cholecystectomy. The bile ducts are usually studied by endoscopic retrograde cholangiopancreatography (ERCP), or, less commonly, trans-hepatic cholangiography. The old technique of intravenous cholangiography has fallen into disrepute because of inconsistent bile-duct opacification. The advent of spiral CT scanning has renewed interest in intravenous cholangiography. The CT technique is very sensitive to the contrast agent in the bile ducts, and angiographic and three-dimensional reconstructions of the biliary tree can readily be obtained using the CT intravenous cholangiogram technique (CT IVC). Seven patients have been studied using this CT IVC technique, between February 1995 and June 1996, and are the subject of the present report. Eight further studies have since been performed. The results suggest that CT IVC could replace ERCP as the primary means of direct cholangiography, where pancreatic duct visualization is not required. (authors)

  3. Computed tomography of the pancreas

    International Nuclear Information System (INIS)

    Kolmannskog, F.; Kolbenstvedt, A.; Aakhus, T.; Bergan, A.; Fausa, O.; Elgjo, K.

    1980-01-01

    The findings by computed tomography in 203 cases of suspected pancreatic tumours, pancreatitis or peripancreatic abnormalities were evaluated. The appearances of the normal and the diseased pancreas are described. Computed tomography is highly accurate in detecting pancreatic masses, but can not differentiate neoplastic from inflammatory disease. The only reliable signs of pancreatic carcinoma are a focal mass in the pancreas, together with liver metastasis. When a pancreatic mass is revealed by computed tomography, CT-guided fine-needle aspiration biopsy of the pancreas is recommended. Thus the need for more invasive diagnostic procedures and explorative laparotomy may be avoided in some patients. (Auth.)

  4. Computed tomography of renal cell carcinoma in patients with terminal renal impairment

    International Nuclear Information System (INIS)

    Ferda, Jiri; Hora, Milan; Hes, Ondrej; Reischig, Tomas; Kreuzberg, Boris; Mirka, Hynek; Ferdova, Eva; Ohlidalova, Kristyna; Baxa, Jan; Urge, Tomas

    2007-01-01

    Purpose: An increased incidence of renal tumors has been observed in patients with end-stage-renal-disease (ESRD). The very strong association with acquired renal cystic disease (ACRD) and increased incidence of the renal tumors (conventional renal cell carcinoma (CRCC), papillary renal cell carcinoma (PRCC) or papillary renal cell adenoma (PRCA)) was reported. This study discusses the role of computed tomography (CT) in detecting renal tumors in patients with renal impairment: pre-dialysis, those receiving dialysis or with renal allograft transplants. Materials and methods: Ten patients (nine male, one female) with renal cell tumors were enrolled into a retrospective study; two were new dialysis patients, three on long-term dialysis, and five were renal transplant recipients with history of dialysis. All patients underwent helical CT, a total of 11 procedures were performed. Sixteen-row detector system was used five times, and a 64-row detector system for the six examinations. All patients underwent nephrectomy of kidney with suspected tumor, 15 nephrectomies were performed, and 1 kidney was assessed during autopsy. CT findings were compared with macroscopic and microscopic assessments of the kidney specimen in 16 cases. Results: Very advanced renal parenchyma atrophy with small cysts corresponding to ESRD was found in nine patients, chronic pyelonephritis in remained one. A spontaneously ruptured tumor was detected incidentally in one case, patient died 2 years later. In the present study, 6.25% (1/16) were multiple PRCA, 12.5% (2/16) were solitary PRCC, 12.5% tumors (2/16) were solitary conventional renal cell carcinomas (CRCC's), 12.5% tumors (2/16) were multiple conventional renal cell carcinomas (CRCC's), 25% (4/16) were CRCC's combined with multiple papillary renal cell carcinomas with adenomas (PRCC's and PRCA's), and 25% (4/16) of the tumors were multiple PRCC's combined with PRCA's without coexisting CRCC's. Bilateral renal tumors were found in our study

  5. Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); The Interuniversity Cardiology Institute of The Netherlands, Utrecht (Netherlands); El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Kroft, Lucia J. [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Younis, Imad Al [Leiden University Medical Center, Department of Nuclear Medicine, Leiden (Netherlands); Reiber, Johan H. [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Medis medical imaging systems B.V., Leiden (Netherlands); Scholte, Arthur J. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands)

    2013-08-15

    Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 {+-} 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS {>=}2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p < 0.001, and OR 1.07, 95 % CI 1.00-1.45, p = 0.032, respectively) after correcting for clinical variables and visually assessed significant stenosis. The addition of quantitatively assessed significant stenosis ({chi} {sup 2} = 20.7) and lesion length ({chi} {sup 2} = 26.0) to the clinical variables and the visual assessment ({chi} {sup 2} = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have

  6. Precision of dosimetry-related measurements obtained on current multidetector computed tomography scanners

    International Nuclear Information System (INIS)

    Mathieu, Kelsey B.; McNitt-Gray, Michael F.; Zhang, Di; Kim, Hyun J.; Cody, Dianna D.

    2010-01-01

    Purpose: Computed tomography (CT) intrascanner and interscanner variability has not been well characterized. Thus, the purpose of this study was to examine the within-run, between-run, and between-scanner precision of physical dosimetry-related measurements collected over the course of 1 yr on three different makes and models of multidetector row CT (MDCT) scanners. Methods: Physical measurements were collected using nine CT scanners (three scanners each of GE VCT, GE LightSpeed 16, and Siemens Sensation 64 CT). Measurements were made using various combinations of technical factors, including kVp, type of bowtie filter, and x-ray beam collimation, for several dosimetry-related quantities, including (a) free-in-air CT dose index (CTDI 100,air ); (b) calculated half-value layers and quarter-value layers; and (c) weighted CT dose index (CTDI w ) calculated from exposure measurements collected in both a 16 and 32 cm diameter CTDI phantom. Data collection was repeated at several different time intervals, ranging from seconds (for CTDI 100,air values) to weekly for 3 weeks and then quarterly or triannually for 1 yr. Precision of the data was quantified by the percent coefficient of variation (%CV). Results: The maximum relative precision error (maximum %CV value) across all dosimetry metrics, time periods, and scanners included in this study was 4.33%. The median observed %CV values for CTDI 100,air ranged from 0.05% to 0.19% over several seconds, 0.12%-0.52% over 1 week, and 0.58%-2.31% over 3-4 months. For CTDI w for a 16 and 32 cm CTDI phantom, respectively, the range of median %CVs was 0.38%-1.14% and 0.62%-1.23% in data gathered weekly for 3 weeks and 1.32%-2.79% and 0.84%-2.47% in data gathered quarterly or triannually for 1 yr. Conclusions: From a dosimetry perspective, the MDCT scanners tested in this study demonstrated a high degree of within-run, between-run, and between-scanner precision (with relative precision errors typically well under 5%).

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

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    Full Text Available ... is Children's CT? Computed tomography, more commonly known as a CT or CAT scan, is a diagnostic ... is used to evaluate: complications from infections such as pneumonia a tumor that arises in the lung ...

  8. Computed tomography of drill cores

    International Nuclear Information System (INIS)

    Taylor, T.

    1985-08-01

    A preliminary computed tomography evaluation of drill cores of granite and sandstone has generated geologically significant data. Density variations as small as 4 percent and fractures as narrow as 0.1 mm were easily detected

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

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    Full Text Available ... Children's (Pediatric) CT (Computed Tomography) Sponsored by Please note RadiologyInfo.org is not a medical facility. Please ... is further reviewed by committees from the American College of Radiology (ACR) and the Radiological Society of ...

  10. Computed Tomography (CT) -- Sinuses

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    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. ...

  11. Computed Tomography (CT) -- Head

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    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. ...

  12. Computed Tomography (CT) -- Head

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    Full Text Available ... top of page Additional Information and Resources RTAnswers.org Radiation Therapy for Brain Tumors Radiation Therapy for ... Tomography (CT) - Head Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ...

  13. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... top of page Additional Information and Resources RTAnswers.org Radiation Therapy for Head and Neck Cancer top ... Tomography (CT) - Sinuses Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ...

  14. Diagnostic assessment of painless microhematuria: prospective study comparing image quality, assessibility and diagnostic certainty of multidetector-row CT and intravenous pyelography within a single examination

    International Nuclear Information System (INIS)

    Boehm, T.; John, H.; Ruedi, C.; Marincek, B.; Wildermuth, S.; Michael, M.

    2005-01-01

    Purpose: The purpose of this study is to prospectively compare intravenous pyelography (IVP) and combined unenhanced and excretory phase multidetector-row CT (MDCT) with respect to image quality, diagnostic certainty and diagnostic concordance with the final clinical diagnosis in patients with painless microhematuria. Materials and Methods: Unenhanced MDCT, IVP and excretory phase MDCT were performed in 59 consecutive patients (21 women, 38 men, mean age 56±19 years, range 23-83 years) with painless microhematuria of unknown origin during a single examination with a single contrast media application (100 ml, non-ionic iodinate contrast media). Images were assessed by two experienced urogenital radiologists in consensus for image quality, diagnostic certainty of stone detection, obstruction, parenchymal lesions and morphological distinctive features. Imaging diagnoses of MDCT and IVP were compared with the final clinical diagnoses. In case of failure to detect an relevant pathology, the final clinical diagnosis was established after a mean follow-up period of 18±6 months (10 months to 2 years). Costs and radiation exposure of IVP and MDCT were compared. Results: MDCT scan performed better than IVP in terms of image quality for all regarded variables. Image quality of MDCT was rated in all parameters as very good or good; the image quality of IVP differed in a wide range. MDCT and IVP reached a sensitivity of 100% and 50% for stone detection (n=14, p=0.008), respectively. Two bladder stones were not detected by IVU but correctly seen with MDCT. MDCT and IVP were unsatisfactory for detecting transitional cell carcinomas (n=4, 2 of 4 detected with MDCT, 0 of 4 detected with IVU). One false positive transitional cell carcinoma was detected with IVP, none with MDCT. Additional relevant pathological changes (one teratoma, one abdominal aortic aneurysma and one abscess) were detected using MDCT but missed with IVP. In 38 of 59 patients (64%) imaging and clinical follow

  15. Neuroanatomy of cranial computed tomography

    International Nuclear Information System (INIS)

    Kretschmann, H.J.; Weinrich, W.

    1985-01-01

    Based on the fundamental structures visualized by means of computed tomography, the authors present the functional systems which are relevant in neurology by means of axial cross-sections. All drawings were prepared from original preparations by means of a new technique which is similar to the grey values of X-ray CT and nuclear magnetic resonance tomography. A detailed description is given of the topics of neurofunctional lesions

  16. Computed Tomography (CT) -- Head

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    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 ...

  17. Computed Tomography (CT) -- Sinuses

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    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 ...

  18. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... ring, called a gantry. The computer workstation that processes the imaging information is located in a separate ... follows a spiral path. A special computer program processes this large volume of data to create two- ...

  19. Computed Tomography (CT) -- Head

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    Full Text Available ... ring, called a gantry. The computer workstation that processes the imaging information is located in a separate ... follows a spiral path. A special computer program processes this large volume of data to create two- ...

  20. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ... ray beam follows a spiral path. A special computer program processes this large volume of data to ...

  1. Computed tomography in renal trauma

    International Nuclear Information System (INIS)

    Brueck, W.; Eisenberger, F.; Buck, J.

    1981-01-01

    In a group of 19 patients suffering from flank trauma and gross hematuria the diagnostic value of angiography was compared with that of computed tomography. The cases that underwent both tests were found to have the some diagnosis of rupture of the kidney. Typical CT-findings in kidney rupture are demonstrated. Whereas angiography presents an exact picture of the arterial system of the kidney, including its injures computed tomography reveals the extent of organ lesons by showing extra- and intrarenal hematomas. If surgery is planned angiography is still mandatory, whereby the indication is largely determined by the clinical findings. Computed tomography as a non-invasive method is equally suitable for follow-ups. (orig.) [de

  2. Computed tomography of pulmonary nodules

    International Nuclear Information System (INIS)

    Nakata, Hajime; Honda, Hiroshi; Nakayama, Chikashi; Kimoto, Tatsuya; Nakayama, Takashi

    1983-01-01

    We have evaluated the value of computed tomography (CT) in distinguishing benign and malignant pulmonary nodules. CT was performed on 30 cases of solitary pulmonary nodules consisting of 17 primary lung cancers, 3 metastatic tumors and 10 benign nodules. The CT number was calculated for each lesion. Three benign nodules showed CT numbers well above the range of malignant nodules, and only in one of them was calcification visible on conventional tomography. In 6 benign nodules, the CT numbers overlapped those of malignant lesion and could not be differentiated. Thus the measurement of CT number can be useful to confirm the benign nature of certain nodules when calcification is unclear or not visible on conventional tomography. As for the morphological observation of the nodule, CT was not superior to conventional tomography and its value seems to be limited. (author)

  3. Emission computed tomography

    International Nuclear Information System (INIS)

    Phelps, M.E.

    1977-01-01

    Although there are many common aspects to x-ray transmission and radionuclide emission (ECT) computerized tomography, there are added difficulties and a number of particular factors which form the basis of ECT. The relationship between the physical factors, system design, methodologic approach and assumptions of ECT is discussed. The instrumentation design and application strategies in ECT at this time are diverse and in a rapid stage of development. The approaches are divided into two major categories of Single Photon Counting (SPC) employing scanner and camera concepts with radionuclides of 99 /sup m/Tc, 201 Tl, 123 I etc., and Annihilation Coincidence Detection (ACD) of positron-emitting radionuclides. Six systems in the former and ten systems in the latter category, with examples of typical studies, illustrate the different approaches

  4. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... diagnose sinusitis . evaluate sinuses that are filled with fluid or thickened sinus membranes . detect the presence of ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  5. Computed Tomography (CT) -- Sinuses

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    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 ...

  6. Computed Tomography (CT) -- Head

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    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 ...

  7. Computed Tomography (CT) -- Head

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    Full Text Available ... path. A special computer program processes this large volume of data to create two-dimensional cross-sectional ... many types of tissue as well as the lungs, bones, and blood vessels. CT examinations are fast ...

  8. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... path. A special computer program processes this large volume of data to create two-dimensional cross-sectional ... many types of tissue as well as the lungs, bones, and blood vessels. CT examinations are fast ...

  9. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... accurate. A major advantage of CT is its ability to image bone, soft tissue and blood vessels ...

  10. Computed Tomography (CT) -- Head

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    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... accurate. A major advantage of CT is its ability to image bone, soft tissue and blood vessels ...

  11. Computed Tomography (CT) -- Head

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    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy ...

  12. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... of the Sinuses? CT is usually the first test ordered when a sinus tumor is suspected. If ...

  13. Computed Tomography (CT) -- Head

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    Full Text Available ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of your body, which are then displayed on a monitor. CT imaging is sometimes compared to looking into ...

  14. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of your body, which are then displayed on a monitor. CT imaging is sometimes compared to looking into ...

  15. Computed Tomography (CT) -- Head

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    Full Text Available ... to reduce the risk of an allergic reaction. These medications must be taken 12 hours prior to ... planes, and can even generate three-dimensional images. These images can be viewed on a computer monitor, ...

  16. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... to reduce the risk of an allergic reaction. These medications must be taken 12 hours prior to ... planes, and can even generate three-dimensional images. These images can be viewed on a computer monitor, ...

  17. Computed Tomography (CT) -- Head

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    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... to you, revolve around you during the imaging process. You will be alone in the exam room ...

  18. Computed Tomography (CT) -- Head

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    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- ...

  19. Computed Tomography (CT) -- Sinuses

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    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- ...

  20. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... path. A special computer program processes this large volume of data to create two-dimensional cross-sectional ... time, resulting in more detail and additional view capabilities. Modern CT scanners are so fast that they ...

  1. Computed Tomography (CT) -- Head

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    Full Text Available ... path. A special computer program processes this large volume of data to create two-dimensional cross-sectional ... time, resulting in more detail and additional view capabilities. Modern CT scanners are so fast that they ...

  2. Computed Tomography (CT) -- Head

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    Full Text Available ... images can be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail ...

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... images can be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail ...

  4. Computed Tomography (CT) -- Head

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    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... cause blurring of the images and degrade the quality of the examination the same way that it ...

  5. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... artifacts on the images. This loss of image quality can resemble the blurring seen on a photograph ...

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

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    Full Text Available ... information about radiation dose. There always is a risk of complications from general anesthesia or sedation. Every measure will be taken to ... in X-Ray and CT Exams Contrast Materials Anesthesia Safety Children and Radiation Safety ... (Pediatric) CT (Computed Tomography) Videos related to Children's (Pediatric) ...

  7. Computed tomography in hepatic echinococcosis

    International Nuclear Information System (INIS)

    Choliz, J.D.; Olaverri, F.J.L.; Casas, T.F.; Zubieta, S.O.

    1982-01-01

    Computed tomography (CT) was used to evaluate 50 cases of hydatid disease of the liver. It was definite in 49 cases and negative in one case. Pre- and postcontrast scans were performed. CT may reveal the exact location and extension of cysts and possible complications. However, a false-negative case was found in a hydatid cyst located in a fatty liver

  8. Computer tomography in Caisson's disease

    International Nuclear Information System (INIS)

    Horvath, F.; Csobaly, S.; Institute for Advanced Training of Physicians, Budapest

    1981-01-01

    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. (orig.) [de

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

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    Full Text Available ... CT (Computed Tomography) Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ... links: For the convenience of our users, RadiologyInfo .org provides links to relevant websites. RadiologyInfo.org , ACR ...

  10. Laryngopyocele: signs on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Nazaroglu, Hasan E-mail: hnazarog@dicle.edu.tr; Oezates, Mustafa; Uyar, Asur; Deger, Emin; Simsek, Masum

    2000-01-01

    A laryngocele is an air-filled dilation of the saccule of the larynx. An infected laryngocele is called a laryngopyocele. Our experience with a case of laryngopyocele with signs on computed tomography before and after antibiotic therapy is presented since laryngopyocele is more unusual.

  11. Laryngopyocele: signs on computed tomography

    International Nuclear Information System (INIS)

    Nazaroglu, Hasan; Oezates, Mustafa; Uyar, Asur; Deger, Emin; Simsek, Masum

    2000-01-01

    A laryngocele is an air-filled dilation of the saccule of the larynx. An infected laryngocele is called a laryngopyocele. Our experience with a case of laryngopyocele with signs on computed tomography before and after antibiotic therapy is presented since laryngopyocele is more unusual

  12. X-ray Computed Tomography.

    Science.gov (United States)

    Michael, Greg

    2001-01-01

    Describes computed tomography (CT), a medical imaging technique that produces images of transaxial planes through the human body. A CT image is reconstructed mathematically from a large number of one-dimensional projections of a plane. The technique is used in radiological examinations and radiotherapy treatment planning. (Author/MM)

  13. 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...

  14. Positron computed tomography with fluorodeoxyglucose

    International Nuclear Information System (INIS)

    Hervouet, T.; Kraeber-Bodere, F.; Lamy, T.; Le Gouil, S.; Devillers, A.; Bodet-Milin, C.; Ansquer, C.; Cheze-le Rest, C.; Metges, J.P.; Teyton, P.; Lozach, P.; Volant, A.; Bizais, Y.; Visvikis, D.; Morel, O.; Girault, S.; Soulie, P.; Dupoiron, D.; Berthelot, C.; Lorimier, G.; Jallet, P.; Garin, E.; Prigent, F.; Lesimple, T.; Barge, M.L.; Rousseau, C.; Devillers, A.; Bernard, A.M.; Bouriel, C.; Bridji, B.; Resche, R.; Banayan, S.; Claret, M.; Ninet, J.; Janier, M.; Billotey, C.; Garin, E.; Devillers, A.; Becker, S.; Lecloirec, J.; Boucher, E.; Raoul, J.L.; Rolland, V.; Oudoux, A.; Valette, F.; Dupas, B.; Moreau, P.; Champion, L.; Anract, P.; Wartski, M.; Laurence, V.; Goldwasser, F.; Pecking, A.P.; Alberini, J.L.; Brillouet, S.; Caselles, O.; Allal, B.; Zerdoud, S.; Gansel, M.G.; Thomas, F.; Dierrickx, L.; Delord, J.P.; Marchand, C.; Resche, I.; Mahe, M.A.

    2006-01-01

    Several oral communications present the interest of positron computed tomography with fluorodeoxyglucose in the detection of cancers, or for the follow up of cancers treatments in order to detect early possible relapses.PET FDG is also used to optimize the definition of target volume in order to avoid side effects and to get a better control of the illness. (N.C.)

  15. 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.

  16. Cranial computed tomography in psychiatry

    International Nuclear Information System (INIS)

    Falkai, P.; Bogerts, B.

    1993-01-01

    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.) [de

  17. Protean appearance of craniopharyngioma on computed tomography

    International Nuclear Information System (INIS)

    Danziger, A.; Price, H.I.

    1979-01-01

    Craniopharyngiomas present a diverse appearance on computed tomography. Histological diagnosis is not always possible, but computed tomography is of great assistance in the delineation of the tumour as well as of the degree of associated hydrocephalus. Computed tomography also enables rapid non-invasive follow-up after surgery or radiotherapy, or both

  18. Industrial applications of computer tomography

    International Nuclear Information System (INIS)

    Sheng Kanglong; Qiang Yujun; Yang Fujia

    1992-01-01

    Industrial computer tomography (CT) and its application is a rapidly developing field of high technology. CT systems have been playing important roles in nondestructive testing (NDT) of products and equipment for a number of industries. Recently, the technique has advanced into the area of industrial process control, bringing even greater benefit to mankind. The basic principles and typical structure of an industrial CT system Descriptions are given of some successful CT systems for either NDT application or process control purposes

  19. Computed tomography of projectile injuries

    International Nuclear Information System (INIS)

    Jeffery, A.J.; Rutty, G.N.; Robinson, C.; Morgan, B.

    2008-01-01

    Computed tomography (CT) is a gold standard in clinical imaging but forensic professions have been slow to embrace radiological advances. Forensic applications of CT are now exponentially expanding, replacing other imaging methods. As post-mortem cross-sectional imaging increases, radiologists will fall under increasing pressure to interpret complex forensic cases involving both living and deceased patients. This review presents a wide variety of weapon and projectile types aiding interpretation of projectile injuries both in forensic and clinical practice

  20. Computed tomography in osteoid osteoma

    International Nuclear Information System (INIS)

    Vicens, J.L.; Aubspin, D.; Buchon, R.; Schoenenberger, P.; Flageat, J.

    1989-01-01

    Four cases of suspected osteoid osteoma were evaluated by computed tomography (CT). The role of CT was related, as a key diagnostic tool: radionuclide imaging is helpful in directing subsequent CT scans, which allows the study of complex anatomical sites (spine) or the analysis of atypical lesions (invisible nidus, sclerosis or lytic lesions, double nidus...). CT provides the surgeon with the exact location and extent of the lesion, and thus, CT may allow a more limited surgical resection of the involved bone [fr

  1. The value of computed tomography in ''sciatica''

    International Nuclear Information System (INIS)

    Boehm-Jurkovic, H.; Hammer, B.

    1981-01-01

    13 cases of therapy-resistant lumboischialgia without herniated disk, caused in 12 cases by a tumour and in 1 case by an abscess, were examined by computed tomography of the lumbar and pelvic region. This method is indicated immediately after insufficient results of conventional X-ray methods (including tomography) and of lumbosacral radiculography. The computed tomography is indispensable also in patients with ''sciatica'' with a known malignoma. The information given by computed tomography is essential for the therapy planning. (author)

  2. Computed tomography of the ossicles

    International Nuclear Information System (INIS)

    Chakeres, D.W.; Weider, D.J.

    1985-01-01

    Otologists and otolaryngologists have described in detail the disorders which are unique to the ossicles. However the anatomy and spectrum of pathology and anatomy of the ossicles are not familiar to most radiologists. Recent advances in computed tomography (CT) and a systematic approach to evaluation now allow accurate identification of even subtle abnormalities of the ossicles. We present the normal anatomy, ossicular abnormalities, and indications for computed tomographic study. Because of the greater diagnostic capability of CT, the radiologist's role has increased in evaluation and treatment planning of patients with suspected ossicular abnormalities. (orig.)

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

    Science.gov (United States)

    ... Disease Venous Thromboembolism Aortic Aneurysm More Cardiac Computed Tomography (Multidetector CT, or MDCT) Updated:Sep 19,2016 What is Computerized Tomography (CT)? CT is a noninvasive test that uses ...

  4. The history of computed tomography

    International Nuclear Information System (INIS)

    Bull, J.

    1980-01-01

    New scientific discoveries are often made by the synthetising of other discoveries. Computed tomography is such an example. The three necessary elements were: 1/ the fact that certain simple crystals scintillate when exposed to X-rays, 2/ the advent of electronics and 3/ that of computers. The fact that X-rays cause crystals to scintillate was learnt very shortly after Roentgen's discovery, electronics and computers coming very much later. To put all these together and apply them to diagnostic radiology, and at the same time dismiss the concept so firmly ingrained in everyone's mind that an X-ray picture must be produced on photographic film, required a genius. (orig./VJ) [de

  5. Computed tomography of stress fracture

    International Nuclear Information System (INIS)

    Murcia, M.; Brennan, R.E.; Edeiken, J.

    1982-01-01

    An athletic young female developed gradual onset of pain in the right leg. Plain radiographs demonstrated solid periosteal reaction in the tibia compatible with stress fracture. She stopped sport activites but her pain continued. Follow-up radiographs of the tibia revealed changes suspicious for osteoid osteoma. Computed tomography (CT) scan demonstrated periosteal reaction, but in addition, lucent fracture lines in the tibial cortex were evident. CT obviated the need for more invasive diagnostic procedures in this patient. In selected cases CT may be useful to confirm the diagnosis of stress fracture when plain radiographic or routine tomographic studies are not diagnostic. (orig.)

  6. Duodenal diverticulitis. computed tomography findings

    International Nuclear Information System (INIS)

    Sanchez, E.; Martin, S.; Garcia, J.; Dominguez, A.

    2001-01-01

    Duodenal diverticular occur very frequently among the general public. However, duodenal diverticulitis is a very uncommon clinical entity, the diagnosis of which requires radiological studies since the clinical signs cam mimic a great number of disease processes with different treatments. We present a case of duodenal diverticulitis in which the diagnosis according to ultrasound and computed tomography (CT) studies was confirmed intraoperatively. We also review the few cases of this entity reported in the literature. The CT findings are highly suggestive of duodenal diverticulitis given their similarity to those associated with diverticulitis at other sites. (Author) 5 refs,

  7. Mathematical foundations of computed tomography

    International Nuclear Information System (INIS)

    Smith, K.T.; Keinert, F.

    1985-01-01

    Along with a review of some of the mathematical foundations of computed tomography, the article contains new results on derivation of reconstruction formulas in a general setting encompassing all standard formulas; discussion and examples of the role of the point spread function with recipes for producing suitable ones; formulas for, and examples of, the reconstruction of certain functions of the attenuation coefficient, e.g., sharpened versions of it, some of them with the property that reconstruction at a point requires only the attenuation along rays meeting a small neighborhood of the point

  8. High speed computer assisted tomography

    International Nuclear Information System (INIS)

    Maydan, D.; Shepp, L.A.

    1980-01-01

    X-ray generation and detection apparatus for use in a computer assisted tomography system which permits relatively high speed scanning. A large x-ray tube having a circular anode (3) surrounds the patient area. A movable electron gun (8) orbits adjacent to the anode. The anode directs into the patient area xrays which are delimited into a fan beam by a pair of collimating rings (21). After passing through the patient, x-rays are detected by an array (22) of movable detectors. Detector subarrays (23) are synchronously movable out of the x-ray plane to permit the passage of the fan beam

  9. Brain metastases: computed tomography assessment

    International Nuclear Information System (INIS)

    Gordillo, Victoria; Yagual, Glenda; Vinueza, Clayreth

    1998-01-01

    Intracranial metastatic tumor is relatively frequent in patients with cancer from other origin. Its location and type of metastasis varies in relation to its linage from the primary tumor. And the sequence goes from the most frequent: lung and breast cancer, melanoma, GU tract, leukemia, GI tract, head and neck tumor. Computed tomography findings are extremely varied and non specific, so there are no radiologic characteristics even from the primary tumor. We reviewed 29 TC studies in the Radiology department of ION-SOLCA, from patients with diagnosis of brain metastasis, our findings showed the great variability in the radio-diagnosis imaging. (The author)

  10. Computed tomography of stress fracture

    International Nuclear Information System (INIS)

    Murcia, M.; Brennan, R.E.; Edeiken, J.

    1982-01-01

    An athletic young female developed gradual onset of pain in the right leg. Plain radiographs demonstrated solid periosteal reaction in the tibia compatible with stress fracture. She stopped sport activites but her pain continued. Follow-up radiographs of the tibia revealed changes suspicious for osteoid osteoma. Computed tomography (CT) scan demonstrated periosteal reaction, but in addition, lucent fracture lines in the tibial cortex were evident. CT obviated the need for more invasive diagnostic procedures in this patient. In selected cases CT may be useful to confirm the diagnosis of stress fracture when plain radiographic or routine tomographic studies are not diagnostic

  11. Whole-body computed tomography

    International Nuclear Information System (INIS)

    Wegener, O.H.

    1992-01-01

    The vast literature on whole-body CT is presented in this bibliography which is published as a self-contained supplement to the monography entitled whole-body CT. For this documentation, the following journals have been scanned back to the year 1980: Journal of Computer Assisted Tomography (JCAT), Fortschritte auf dem Gebiet der Roentgenstrahlen (RoeFo), Radiology, American Journal of Roentgenology (AJR), Der Radiologe, Neuroradiology, and American Journal of Neuroradiology (AJNR). The supplement includes keyword indexes that can be searched for terms indicating body organs, body regions, or certain lesions. The author index offers an additional access to the publication wanted. (orig./MG) [de

  12. Novel imaging strategies for the detection of prosthetic heart valve obstruction and endocarditis

    NARCIS (Netherlands)

    Tanis, W; Budde, R P J; van der Bilt, I A C; Delemarre, B; Hoohenkerk, G; van Rooden, J-K; Scholtens, A M; Habets, J; Chamuleau, S

    Prosthetic heart valve (PHV) dysfunction remains difficult to recognise correctly by two-dimensional (2D) transthoracic and transoesophageal echocardiography (TTE/TEE). ECG-triggered multidetector-row computed tomography (MDCT), 18-fluorine-fluorodesoxyglucose positron emission tomography including

  13. Dose determination in computed tomography

    International Nuclear Information System (INIS)

    Descamps, C.; Garrigo, E.; Venencia, D.; Gonzalez, M.; Germanier, A.

    2011-10-01

    In the last years the methodologies to determine the dose in computed tomography have been revised. In this work was realized a dosimetric study about the exploration protocols used for simulation of radiotherapy treatments. The methodology described in the Report No. 111 of the American Association of Medical Physiques on a computed tomograph of two cuts was applied. A cylindrical phantom of water was used with dimensions: 30 cm of diameter and 50 cm of longitude that simulates the absorption and dispersion conditions of a mature body of size average. The doses were determined with ionization chamber and thermoluminescent dosimetry. The results indicate that the dose information that provides the tomograph underestimates the dose between 32 and 35%.

  14. Computed tomography of the spine

    International Nuclear Information System (INIS)

    Isherwood, I.; Antoun, N.M.

    1984-01-01

    Until the advent of Computed Tomography (CT), axial studies of the spine were limited in the main to gross bony anatomy and to conventional transaxial tomography (TAT). Others studied the upper cervical cord in transverse section during gas myelography and encephalography. The potential role of CT in the evaluation of spinal anatomy and disease was recognized, however, at an early stage in the development of the general purpose CT scanner. CT is not organ specific and therefore provides a uniformly thin (1.5-13 mm) axial section displaying detailed spinal topographical anatomy against a background of paravertebral muscles, vascular structures and body cavity organs. The relationships of the apophyseal joints to the spinal canal and intervertebral foramina are particularly well displayed. The study of neural tissue and pathology within the spinal canal is facilitated by the use of a non-ionic water-soluble contrast medium (viz. metrizamide) in the subarachnoid spaces. The high sensitivity of CT to very small changes in X-ray attenuation permits studies to be continued over several hours. The digital derivation of the sequential CT transaxial sections enables not only interrogation of data and quantitative studies to be made but also makes possible computer-generated reconstructions in other planes

  15. Motion artifacts in computed tomography

    International Nuclear Information System (INIS)

    Yang, C.K.

    1979-01-01

    In the year 1972, the first Computed Tomography Scanner (or CT) was introduced and caused a revolution in the field of Diagnostic Radiology. A tomogram is a cross-sectional image of a three-dimensional object obtained through non-invasive measurements. The image that is presented is very similar to what would be seen if a thin cross-sectional slice of the patient was examined. In Computed Tomography, x-rays are passed through the body of a patient in many different directions and their attenuation is detected. By using some mathematical theorems, the attenuation information can be converted into the density of the patient along the x-ray path. Combined with modern sophisticated computer signal processing technology, a cross-sectional image can be generated and displayed on a TV monitor. Usually a good CT image relies on the patient not moving during the x-ray scanning. However, for some unconscious or severely ill patients, this is very difficult to achieve. Thus, the motion during the scan causes the so-called motion artifacts which distort the displayed image and sometimes these motion artifacts make diagnosis impossible. Today, to remove or avoid motion artifacts is one of the major efforts in developing new scanner systems. In this thesis, a better understanding of the motion artifacts problem in CT scaning is gained through computer simulations, real scanner experiments and theoretical analyses. The methods by which the distorted image can be improved are simulated also. In particular, it is assumed that perfect knowledge of the patient motion is known since this represents the theoretical limit on how well the distorted image can be improved

  16. Batch Computed Tomography Analysis of Projectiles

    Science.gov (United States)

    2016-05-01

    ARL-TR-7681 ● MAY 2016 US Army Research Laboratory Batch Computed Tomography Analysis of Projectiles by Michael C Golt, Chris M...Laboratory Batch Computed Tomography Analysis of Projectiles by Michael C Golt and Matthew S Bratcher Weapons and Materials Research...values to account for projectile variability in the ballistic evaluation of armor. 15. SUBJECT TERMS computed tomography , CT, BS41, projectiles

  17. Comparison of traditional cardiovascular risk models and coronary atherosclerotic plaque as detected by computed tomography for prediction of acute coronary syndrome in patients with acute chest pain.

    Science.gov (United States)

    Ferencik, Maros; Schlett, Christopher L; Bamberg, Fabian; Truong, Quynh A; Nichols, John H; Pena, Antonio J; Shapiro, Michael D; Rogers, Ian S; Seneviratne, Sujith; Parry, Blair Alden; Cury, Ricardo C; Brady, Thomas J; Brown, David F; Nagurney, John T; Hoffmann, Udo

    2012-08-01

    The objective was to determine the association of four clinical risk scores and coronary plaque burden as detected by computed tomography (CT) with the outcome of acute coronary syndrome (ACS) in patients with acute chest pain. The hypothesis was that the combination of risk scores and plaque burden improved the discriminatory capacity for the diagnosis of ACS. The study was a subanalysis of the Rule Out Myocardial Infarction Using Computer-Assisted Tomography (ROMICAT) trial-a prospective observational cohort study. The authors enrolled patients presenting to the emergency department (ED) with a chief complaint of acute chest pain, inconclusive initial evaluation (negative biomarkers, nondiagnostic electrocardiogram [ECG]), and no history of coronary artery disease (CAD). Patients underwent contrast-enhanced 64-multidetector-row cardiac CT and received standard clinical care (serial ECG, cardiac biomarkers, and subsequent diagnostic testing, such as exercise treadmill testing, nuclear stress perfusion imaging, and/or invasive coronary angiography), as deemed clinically appropriate. The clinical providers were blinded to CT results. The chest pain score was calculated and the results were dichotomized to ≥10 (high-risk) and modeling was performed to examine the association of risk scores and coronary plaque burden to the outcome of ACS. Unadjusted models were individually fitted for the coronary plaque burden and for Goldman, Sanchis, TIMI, and chest pain scores. In adjusted analyses, the authors tested whether the association between risk scores and ACS persisted after controlling for the coronary plaque burden. The prognostic discriminatory capacity of the risk scores and plaque burden for ACS was assessed using c-statistics. The differences in area under the receiver-operating characteristic curve (AUC) and c-statistics were tested by performing the -2 log likelihood ratio test of nested models. A p value capacity for the diagnosis of ACS. Plaque burden was

  18. Comparison of gated blood pool SPECT and spiral multidetector computed tomography in the assessment of right ventricular functional parameters. Validation with first-pass radionuclide angiography

    International Nuclear Information System (INIS)

    Lee, Jung S.; Kim, Seong-Jang; Kim, In-Ju; Kim, Yong-Ki; Choo, Ki S.; Lee, Jun S.

    2007-01-01

    The aim of this study was to compare gated blood pool single photon emission computed tomography (SPECT) (GBPS) and multidetector row computed tomography (MDCT) for the determination of right ventricular ejection fraction (RVEF) and right ventricular volumes (RVV) and to compare first-pass radionuclide angiography (FP-RNA) as the gold standard. Twenty consecutive patients (11 men, 9 women) referred for MDCT for the evaluation of the presence of coronary artery disease underwent FP-RNA and GBPS. The mean right ventricular end-diastolic volume (EDV) calculated with GBPS revealed a statistically significant lower value than that of MDCT. The mean right ventricular end-systolic volume (ESV) calculated with GBPS was also lower than that of MDCT. A comparison of right ventricular EDV from GBPS and MDCT yielded a correlation coefficient of 0.5972. Right ventricular ESV between GBPS and MDCT showed a correlation coefficient of 0.5650. The mean RVEFs calculated with FP-RNA (39.8%±4.0%), GBPS (43.7%±6.9%), and MDCT (40.4%±7.7%) showed no statistical differences (Kruskal-Wallis statistics 4.538, P=0.1034). A comparison of RVEFs from FP-RNA and GBPS yielded a correlation coefficient of 0.7251; RVEFs between FP-RNA and MDCT showed a correlation coefficient of 0.6166 and between GBPS and MDCT showed a correlation coefficient of 0.6367. The RVEF, EDV, and ESV calculated by GBPS had good correlation with those obtained with MDCT. In addition, there were no statistical differences of RVEF calculated from FP-RNA, GBPS, and MDCT. However, with regard to RVV, EDV and ESV from GBPS revealed statistically significantly lower values than those of MDCT. Although reasonable correlations among these modalities were obtained, the agreement among these three modalities was not good enough for interchangeable use in the clinical setting. Also, these results should be confirmed in patients with cardiac diseases in future larger population-based studies. (author)

  19. Measuring Weld Profiles By Computer Tomography

    Science.gov (United States)

    Pascua, Antonio G.; Roy, Jagatjit

    1990-01-01

    Noncontacting, nondestructive computer tomography system determines internal and external contours of welded objects. System makes it unnecessary to take metallurgical sections (destructive technique) or to take silicone impressions of hidden surfaces (technique that contaminates) to inspect them. Measurements of contours via tomography performed 10 times as fast as measurements via impression molds, and tomography does not contaminate inspected parts.

  20. Noninvasive coronary angioscopy using electron beam computed tomography and multidetector computed tomography

    NARCIS (Netherlands)

    van Ooijen, PMA; Nieman, K; de Feyter, PJ; Oudkerk, M

    2002-01-01

    With the advent of noninvasive coronary imaging techniques like multidetector computed tomography and electron beam computed tomography, new representation methods such as intracoronary visualization. have been introduced. We explore the possibilities of these novel visualization techniques and

  1. An introduction to emission computed tomography

    International Nuclear Information System (INIS)

    Williams, E.D.

    1985-01-01

    This report includes salient features of the theory and an examination of practical considerations for someone who is using or introducing tomography, selecting equipment for it or wishing to develop a clinical application. Emphasis is on gamma camera tomography. The subject is dealt with under the following headings: emission computed and gamma camera tomography and the relationship to other medical imaging techniques, the tomographic reconstruction technique theory, rotating gamma camera tomography, attenuation correction and quantitative reconstruction, other single photon tomographic techniques, positron tomography, image display, clinical application of single photon and positron tomography, and commercial systems for SPECT. Substantial bibliography. (U.K.)

  2. Computed tomography of surface related radionuclide distributions ('BONN'-tomography)

    International Nuclear Information System (INIS)

    Bockisch, A.; Koenig, R.

    1989-01-01

    A method called the 'BONN' tomography is described to produce planar projections of circular activity distributions using standard single photon emission computed tomography. The clinical value of the method is demonstrated for bone scans of the jaw, thorax, and pelvis. Numerical or projection-related problems are discussed. (orig.) [de

  3. Computed tomography of splenic trauma

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey, R.B.; Laing, F.C.; Federle, M.P.; Goodman, P.C.

    1981-12-01

    Fifty patients with abdominal trauma and possible splenic injury were evaluated by computed tomography (CT). CT correctly diagnosed 21 of 22 surgically proved traumatic sesions of the spleen (96%). Twenty-seven patients had no evidence of splenic injury. This was confirmed at operation in 1 patient and clinical follow-up in 26. There were one false negative and one false positive. In 5 patients (10%), CT demonstrated other clinically significant lesions, including hepatic or renal lacerations in 3 and large retroperitoneal hematomas in 2. In adolescents and adults, CT is an accurate, noninvasive method of rapidly diagnosing splenic trauma and associated injuries. Further experience is needed to assess its usefulness in evaluating splenic injuries in infants and small children.

  4. Computed tomography of splenic trauma

    International Nuclear Information System (INIS)

    Jeffrey, R.B.; Laing, F.C.; Federle, M.P.; Goodman, P.C.

    1981-01-01

    Fifty patients with abdominal trauma and possible splenic injury were evaluated by computed tomography (CT). CT correctly diagnosed 21 of 22 surgically proved traumatic sesions of the spleen (96%). Twenty-seven patients had no evidence of splenic injury. This was confirmed at operation in 1 patient and clinical follow-up in 26. There were one false negative and one false positive. In 5 patients (10%), CT demonstrated other clinically significant lesions, including hepatic or renal lacerations in 3 and large retroperitoneal hematomas in 2. In adolescents and adults, CT is an accurate, noninvasive method of rapidly diagnosing splenic trauma and associated injuries. Further experience is needed to assess its usefulness in evaluating splenic injuries in infants and small children

  5. Computed tomography in sport injuries

    International Nuclear Information System (INIS)

    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. (orig.)

  6. 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.

  7. Computed tomography in hepatic trauma

    International Nuclear Information System (INIS)

    Moon, K.L. Jr.; Federle, M.P.

    1983-01-01

    Twenty-five patients with hepatic injury from blunt upper abdominal trauma were examined by computed tomography (CT). The spectrum of CT findings was recorded, and the size of the hepatic laceration and the associated hemoperitoneum were correlated with the mode of therapy used in each case (operative vs nonoperative). While the need for surgery correlated roughly with the size of the hepatic laceration, the size of the associated hemoperitoneum was an important modifying factor. Fifteen patients with hepatic lacerations but little or no hemoperitoneum were managed nonoperatively. CT seems to have significant advantages over hepatic scintigraphy, angiography, and diagnostic peritoneal lavage. By combining inforamtion on the clinical state of the patient and CT findings, therapy of hepatic injury can be individualized and the incidence of nontherapeutic laparotomies decreased

  8. Computed tomography of cryogenic cells

    International Nuclear Information System (INIS)

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

    2001-01-01

    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. Radiological protection in computed tomography and cone beam computed tomography.

    Science.gov (United States)

    Rehani, M M

    2015-06-01

    The International Commission on Radiological Protection (ICRP) has sustained interest in radiological protection in computed tomography (CT), and ICRP Publications 87 and 102 focused on the management of patient doses in CT and multi-detector CT (MDCT) respectively. ICRP forecasted and 'sounded the alarm' on increasing patient doses in CT, and recommended actions for manufacturers and users. One of the approaches was that safety is best achieved when it is built into the machine, rather than left as a matter of choice for users. In view of upcoming challenges posed by newer systems that use cone beam geometry for CT (CBCT), and their widened usage, often by untrained users, a new ICRP task group has been working on radiological protection issues in CBCT. Some of the issues identified by the task group are: lack of standardisation of dosimetry in CBCT; the false belief within the medical and dental community that CBCT is a 'light', low-dose CT whereas mobile CBCT units and newer applications, particularly C-arm CT in interventional procedures, involve higher doses; lack of training in radiological protection among clinical users; and lack of dose information and tracking in many applications. This paper provides a summary of approaches used in CT and MDCT, and preliminary information regarding work just published for radiological protection in CBCT. © The International Society for Prosthetics and Orthotics Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  10. Computed tomography and three-dimensional imaging

    International Nuclear Information System (INIS)

    Harris, L.D.; Ritman, E.L.; Robb, R.A.

    1987-01-01

    Presented here is a brief introduction to two-, three-, and four-dimensional computed tomography. More detailed descriptions of the mathematics of reconstruction and of CT scanner operation are presented elsewhere. The complementary tomographic imaging methods of single-photon-emission tomography (SPECT) positron-emission tomography (PET), nuclear magnetic resonance (NMR) imaging, ulltrasound sector scanning, and ulltrasound computer-assisted tomography [UCAT] are only named here. Each imaging modality ''probes'' the body with a different energy form, yielding unique and useful information about tomographic sections through the body

  11. Intravenous contrast medium administration at 128 multidetector row CT pulmonary angiography: Bolus tracking versus test bolus and the implications for diagnostic quality and effective dose

    International Nuclear Information System (INIS)

    Rodrigues, J.C.L.; Mathias, H.; Negus, I.S.; Manghat, N.E.; Hamilton, M.C.K.

    2012-01-01

    Aim: To investigate the effects of a test bolus protocol contrast medium administration on diagnostic image quality in computed tomography pulmonary angiography (CTPA). Materials and methods: Fifty patients referred for exclusion of pulmonary embolism underwent CTPA using a test bolus protocol CTPA at 120 kVp and were compared with 50 patients undergoing CTPA using a standard bolus-tracking protocol at 120 kVp, via assessment of attenuation, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) seen in the pulmonary arteries (PAs). An additional group of 10 non-obese patients who underwent CTPA using a test bolus protocol performed at 100 kVp were also analysed. Mean effective dose was calculated from the dose–length product, using standard conversion factors. Results: The test bolus protocol showed significantly higher attenuation, SNR, and CNR in the pulmonary vasculature down to the segmental level compared to bolus-tracking CTPA (p < 0.0001). There was no significant difference in effective dose between the test bolus and bolus tracking cohorts. The additional group of test bolus CTPA examinations performed at 100 kVp had a significantly reduced effective dose in comparison to both test bolus CTPA at 120 kVp and bolus-tracking CTPA at 120 kVp (p < 0.005) yet maintained mean PA attenuation to segmental level significantly better than bolus-tracking CTPA performed at 120 kVp and comparable to the test bolus cohort performed at 120 kVp. Conclusion: Test bolus contrast administration should be used as an optimal protocol. Performing test bolus CTPA at 100 kVp, as opposed to 120 kVp, significantly reduces dose without compromising PA attenuation in non-obese subjects.

  12. Computed tomography of obstructive jaundice

    International Nuclear Information System (INIS)

    Suh, Jung Hek; Lee, Joong Suk; Chun, Beung He; Suh, Soo Jhi

    1982-01-01

    It is well known that the computed tomography (CT) is very useful in the evaluation of obstructive jaundice. We have studied 55 cases of obstructive jaundice with whole body scanner from Jun.1980 to Jun. 1981. The results were as follows: 1. The sex distribution was 36 males and 19 females, and 40 cases of obstructive jaundice were seen in fifth, sixth, and seventh decades. 2. Causes of obstructive jaundice were 25 cases of pancreas cancer, 8 cases of common duct cancer, 4 cases of gallbladder cancer, 4 cases of ampulla vater cancer, 12 cases of common duct stone, and 2 cases of common duct stricture. 3. Levels of obstruction were 8 cases of hepatic portion, 15 cases of suprapancreatic portion, 28 cases of pancreatic portion, and 4 cases of ampullary portion. 4. In tumorous condition, CT demonstrated metastasis of other organs, 9 cases of the liver, 1 case of the lung, 3 cases of the pancreas, 3 cases of the common bile duct, 1 case of the stomach, and 12 cases of adjacent lymph nodes. 5. Associated diseases were 12 cases of intrahepatic stone, 4 cases of clonorchiasis, 2 cases of pancreas pseudocyst, 1 cases of hydronephrosis, and 1 case of renal cyst

  13. Errors in abdominal computed tomography

    International Nuclear Information System (INIS)

    Stephens, S.; Marting, I.; Dixon, A.K.

    1989-01-01

    Sixty-nine patients are presented in whom a substantial error was made on the initial abdominal computed tomography report. Certain features of these errors have been analysed. In 30 (43.5%) a lesion was simply not recognised (error of observation); in 39 (56.5%) the wrong conclusions were drawn about the nature of normal or abnormal structures (error of interpretation). The 39 errors of interpretation were more complex; in 7 patients an abnormal structure was noted but interpreted as normal, whereas in four a normal structure was thought to represent a lesion. Other interpretive errors included those where the wrong cause for a lesion had been ascribed (24 patients), and those where the abnormality was substantially under-reported (4 patients). Various features of these errors are presented and discussed. Errors were made just as often in relation to small and large lesions. Consultants made as many errors as senior registrar radiologists. It is like that dual reporting is the best method of avoiding such errors and, indeed, this is widely practised in our unit. (Author). 9 refs.; 5 figs.; 1 tab

  14. Brain perfusion: computed tomography applications

    International Nuclear Information System (INIS)

    Miles, K.A.

    2004-01-01

    Within recent years, the broad introduction of fast multi-detector computed tomography (CT) systems and the availability of commercial software for perfusion analysis have made cerebral perfusion imaging with CT a practical technique for the clinical environment. The technique is widely available at low cost, accurate and easy to perform. Perfusion CT is particularly applicable to those clinical circumstances where patients already undergo CT for other reasons, including stroke, head injury, subarachnoid haemorrhage and radiotherapy planning. Future technical developments in multi-slice CT systems may diminish the current limitations of limited spatial coverage and radiation burden. CT perfusion imaging on combined PET-CT systems offers new opportunities to improve the evaluation of patients with cerebral ischaemia or tumours by demonstrating the relationship between cerebral blood flow and metabolism. Yet CT is often not perceived as a technique for imaging cerebral perfusion. This article reviews the use of CT for imaging cerebral perfusion, highlighting its advantages and disadvantages and draws comparisons between perfusion CT and magnetic resonance imaging. (orig.)

  15. X-ray computed tomography

    International Nuclear Information System (INIS)

    Kalender, Willi A

    2006-01-01

    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. (review)

  16. Computed tomography of epileptic children

    International Nuclear Information System (INIS)

    Kurihara, Mana; Yamashita, Sumimasa; Miyake, Shota; Yamada, Michiko; Iwamoto, Hiroko

    1986-01-01

    The aim of this study was to analyze the changes seen on cranial computed tomography (CT) of epileptic children, especially in the area of the temporal horn. The subjects were 242 epileptic children excluding those with encephalitis, brain tumor, neurocutaneous syndromes, degenerative disease, hydrocephalus etc. The control subjects were 195 children without any neurological disease and symptoms. CT scan were taken with a TCT-60A whole body scanner, and 14 check points were evaluated excluding the temporal horn. 195 epileptic children (N-group) and all control children were normal at 14 check points. Next, the areas of the temporal horns and adjoining hemispheres of the epileptic children (N-group) and control children were examined with Muto-Tablet-Desitizer. The temporal horn ratio ((area of temporal horn/area of ipsilateral hemisphere) x 100) was greater in younger children of the control group, and it was higher in epileptic than in control children. Enlargement of the temporal horn was seen in 1 % of the controls and in 35 % of the 125 epileptic children with normal measurements at 14 points on CT scans (p < 0.01). The frequency of enlargement of temporal horns was not variable among different epileptic types. In the epileptic children with normal CT scans except for enlargement of temporal horns behavioral disturbances were 6 boys and 5 had enlarged temporal horns (bilateral 1 case, left side 1 case, right side 3 cases). (author)

  17. Computed Tomography of Interacerebral Hemorrhage

    International Nuclear Information System (INIS)

    Kim, Seung Hyeon; Lee, Jong Beum; Lee, Yong Chul; Lee, Kwan Seh; Park, Soo Soung

    1983-01-01

    Computed tomography (CT) is the most accurate and reliable method for the diagnosis of intracerebral and intraventricular hemorrhage. The precise anatomic extent of the nematoma, associated cerebral edema, ventricular deformity and displacement, and hydrocephalus are all readily assessed. Aside from head trauma, the principal cause of intracerebral hematoma is hypertensive vascular disease. Although hematomas from various causes may present similar CT appearances frequently the correct etiology may be suggested by consideration of patient's age, clinical history, and the location of the hematoma. The analytical study was performed in 180 cases of intracerebral hemorrhages by CT from October 1981 to January 1983. The results were as follows; 1. The most prevalent age group was 6th decade (37.2%). Male was prevalent to female at the ration of 1.6 to 1. 2. The most common symptom and sign was mental disturbance (48.7%), motor weakness (23%), headache (10.6%), nausea and vomiting (9.8%). 3. The causes of hemorrhage were hypertension (53.9%), head trauma (30.6%), aneurysm (6.1%) and A-V malformation (7.2%). 4. The frequent locations of hemorrhage were basal ganglia and thalamus (40.4%), lobes (35%), ventricles (21.8%). 5. The distribution of hemorrhage was intracerebral hemorrhage (65.6%), intracerebral and intraventricular hemorrhage (30.3%), intraventricular hemorrhage (4.4%).

  18. Recent Developments in Computed Tomography

    International Nuclear Information System (INIS)

    Braunstein, D.; Dafni, E.; Levene, S.; Malamud, G.; Shapiro, O.; Shechter, G.; Zahavi, O.

    1999-01-01

    Computerized Tomography. has become, during the past few years, one of the mostly used apparatus in X-ray diagnosis. Its clinical applications has penetrated to various fields, like operational guidance, cardiac imaging, computer aided surgery etc. The first second-generation CT scanners consisted of a rotate-rotate system detectors array and an X-ray tube. These scanners were capable of acquiring individual single slices, the duration of each being several seconds. The slow scanning rate, and the then poor computers power, limited the application range of these scanners, to relatively stable organs, short body coverage at given resolutions. Further drawbacks of these machines were weak X-ray sources and low efficiency gas detectors. In the late 80's the first helical scanners were introduced by Siemens. Based on a continuous patient couch movement during gantry rotation, much faster scans could be obtained, increasing significantly the volume coverage at a given time. In 1992 the first dual-slice scanners, equipped with high efficiency solid state detectors were introduced by Elscint. The acquisition of data simultaneously from two detector arrays doubled the efficiency of the scan. Faster computers and stronger X-ray sources further improved the performance, allowing for a new range of clinical applications. Yet, the need for even faster machines and bigger volume coverage led to further R and D efforts by the leading CT manufacturers. In order to accomplish the most demanding clinical needs, innovative 2 dimensional 4-rows solid-state detector arrays were developed, together with faster rotating machines and bigger X-ray tubes, all demanding extremely accurate and robust mechanical constructions. Parallel, multi-processor custom computers were made, in order to allow the on-line reconstruction of the growing amounts of raw data. Four-slice helical scanners, rotating at 0.5 sec per cycle are being tested nowadays in several clinics all over the world. This talk

  19. Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography in Disseminated Cryptococcosis.

    Science.gov (United States)

    Tripathy, Sarthak; Parida, Girish Kumar; Roy, Shambo Guha; Singhal, Abhinav; Mallick, Saumya Ranjan; Tripathi, Madhavi; Shamim, Shamim Ahmed

    2017-01-01

    Disseminated cryptococcosis without pulmonary involvement is a very rare phenomenon. Patterns of organ involvement in cryptococcosis resemble various other infective conditions as well as malignant conditions on fluorodeoxyglucose positron emission tomography-computed tomography. We present a case of a 43-year-old male patient who had disseminated cryptococcosis. The rarity of the case being noninvolvement of lungs and meninges and resembling more like lymphoma due to the diffuse involvement of the lymph nodes on both sides of the diaphragm.

  20. Computed tomography of the facial canal

    International Nuclear Information System (INIS)

    Kiuchi, Sousuke

    1983-01-01

    The radiological details of the facial canal was investigated by computed tomography. In the first part of this study, dry skulls were used to delineate the full course of the facial canal by computed tomography. In the second part of this study, the patients with chronic otitis media and secondary cholesteatoma were evaluated. The labyrinthine and tympanic parts of the canal were well demonstrated with the axial scanning, and the mastoid part with the coronal scanning. Moreover, computed tomography showed excellent delineation of the middle ear contents. In patients with secondary cholesteatoma, the destructions of the intratympanic course of the bony facial canal were also assessed preoperatively. (author)

  1. Novel imaging strategies for the detection of prosthetic heart valve obstruction and endocarditis

    NARCIS (Netherlands)

    W. Tanis (Wilco); R.P.J. Budde (Ricardo); I.A.C. van der Bilt (Ivo); B. Delemarre; G. Hoohenker; J.-K. Van Rooden; A.M. Scholtens (Asbjørn M.); J. Habets; S.A.J. Chamuleau (Steven)

    2016-01-01

    textabstractProsthetic heart valve (PHV) dysfunction remains difficult to recognise correctly by two-dimensional (2D) transthoracic and transoesophageal echocardiography (TTE/TEE). ECG-triggered multidetector-row computed tomography (MDCT), 18-fluorine-fluorodesoxyglucose positron emission

  2. Attenuation Correction Strategies for Positron Emission Tomography/Computed Tomography and 4-Dimensional Positron Emission Tomography/Computed Tomography

    OpenAIRE

    Pan, Tinsu; Zaidi, Habib

    2013-01-01

    This article discusses attenuation correction strategies in positron emission tomography/computed tomography (PET/CT) and 4 dimensional PET/CT imaging. Average CT scan derived from averaging the high temporal resolution CT images is effective in improving the registration of the CT and the PET images and quantification of the PET data. It underscores list mode data acquisition in 4 dimensional PET and introduces 4 dimensional CT popular in thoracic treatment planning to 4 dimensional PET/CT. ...

  3. Orbital computed tomography for exophthalmos

    International Nuclear Information System (INIS)

    Kim, Ok Keun; Lee, Hyun; Sol, Chang Hyo; Kim, Byung Soo

    1987-01-01

    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

  4. Computed tomography of cerebrovascular accidents

    International Nuclear Information System (INIS)

    Lee, Jong Deuk; Moon, Yang In; Lim, Se Hwan; Lee, Cheorl Woo; Kim, Byung Chan; Won, Jong Jin

    1989-01-01

    Computed tomography (CT) is an accurate and noninvasive method in the evaluation of cerebrovascular accidents (CVA) for detection of nature, location, extension and associated changes. Retrospective analysis was done in 402 patients of clinically suspected CVA who were performed CT in our hospital from December 1985 to December 1987. The results were as follows; 1. The analysis of CT findings in 402 patients showed 321 cases of CVA, 79 cases of normal findings, and 2 cases of brain tumors. 2. Among 321 cases of CVA, intracerebral hemorrhage was noted in 158 cases, cerebral infarction in 126 cases, and subarachnoid hemorrhage in 37 cases. 3. The common sites of cerebral hemorrhage were basal ganglia in 99 cases, especially putamen, thalamus in 32 cases, and cerebrum, cerebellum in 11 cases respectively. Cerebral infarction was found chiefly at the areas distributed by the middle cerebral artery: cerebral lobe 55 cases and basal ganglia 51 cases. The aneurysm was the most common cause of subarachnoid hemorrhage, and its common site was posterior communicating artery and middle cerebral artery areas. 4. The common shape of cerebral infarction was oval in basal ganglia and wedged in the cerebral lobes. The contrast enhancement of the cerebral infarction was observed in 10% of cases between the 3rd days and 2nd weeks after onset, and was usually gyral patients (77.7%). 5. The aneurysm was noted as enhancing nodule on contrast CT in all 14 cases. In conclusion, the most common cause of CVA is intracerebral hemorrhage in Iri, Korea. High resolution contrast enhanced CT can be used in the diagnosis of the ruptured cerebral aneurysm without the aid of cerebral angiography

  5. Computed tomography of cerebrovascular accidents

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Deuk; Moon, Yang In; Lim, Se Hwan; Lee, Cheorl Woo; Kim, Byung Chan; Won, Jong Jin [Wonkwang University School of Medicine, Iri (Korea, Republic of)

    1989-10-15

    Computed tomography (CT) is an accurate and noninvasive method in the evaluation of cerebrovascular accidents (CVA) for detection of nature, location, extension and associated changes. Retrospective analysis was done in 402 patients of clinically suspected CVA who were performed CT in our hospital from December 1985 to December 1987. The results were as follows; 1. The analysis of CT findings in 402 patients showed 321 cases of CVA, 79 cases of normal findings, and 2 cases of brain tumors. 2. Among 321 cases of CVA, intracerebral hemorrhage was noted in 158 cases, cerebral infarction in 126 cases, and subarachnoid hemorrhage in 37 cases. 3. The common sites of cerebral hemorrhage were basal ganglia in 99 cases, especially putamen, thalamus in 32 cases, and cerebrum, cerebellum in 11 cases respectively. Cerebral infarction was found chiefly at the areas distributed by the middle cerebral artery: cerebral lobe 55 cases and basal ganglia 51 cases. The aneurysm was the most common cause of subarachnoid hemorrhage, and its common site was posterior communicating artery and middle cerebral artery areas. 4. The common shape of cerebral infarction was oval in basal ganglia and wedged in the cerebral lobes. The contrast enhancement of the cerebral infarction was observed in 10% of cases between the 3rd days and 2nd weeks after onset, and was usually gyral patients (77.7%). 5. The aneurysm was noted as enhancing nodule on contrast CT in all 14 cases. In conclusion, the most common cause of CVA is intracerebral hemorrhage in Iri, Korea. High resolution contrast enhanced CT can be used in the diagnosis of the ruptured cerebral aneurysm without the aid of cerebral angiography.

  6. 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.

  7. Image quality in coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Precht, Helle; Gerke, Oke; Thygesen, Jesper

    2018-01-01

    Background Computed tomography (CT) technology is rapidly evolving and software solution developed to optimize image quality and/or lower radiation dose. Purpose To investigate the influence of adaptive statistical iterative reconstruction (ASIR) at different radiation doses in coronary CT...

  8. Evaluation of computed tomography for obstructive jaundice

    International Nuclear Information System (INIS)

    Matsuoka, Shoji; Toda, Hiroshi; Suzuki, Toshihiko

    1980-01-01

    Findings of computed tomography were reviewed in 54 cases where obstructive jaundice was suggested by liver function studies and computed tomography was done with the diagnosis subsequently confirmed by surgery. Dilatation of the intrahepatic bile duct was found in 49 (91%) of the cases and the site of obstruction was determined in 44 cases (82%). The cause was shown in 28 cases (52%). By disease, the cause was correctly diagnosed with gallbladder in 40%, bile duct cancer in 46%, pancreas cancer in 71%, and choledocal cyst in 100%, but cholelithiasis was diagnosed correctly in only 17%. Further, non-calcium cholelithiasis is very difficult to diagnose by computed tomography. Computed tomography is a useful tool for diagnosis of obstructive jaundice as a noninvasive means of evaluating the patient; however, concomitand use of other diagnostic studies is essential for greater accuracy of diagnosis. (author)

  9. Computed tomography and/or ventriculography

    International Nuclear Information System (INIS)

    Wende, S.; Kishikawa, T.; Huewel, N.; Kazner, E.; Grumme, T.; Lanksch, W.

    1982-01-01

    It is discussed if in intracranial tumors, especially in tumors of the posterior cranial fossa, a CT and/or a ventriculography should be practiced. We have made investigations of 134 patients, 93 of whom were children up to 14 years of age. Each case was undertaken computed tomography as well as ventriculography. The results are clearly demonstrating the superiority of computed tomography compared with ventriculography. Ventriculography is a surgical intervention stressing the patients, side-effects may occur, and sometimes serious complications are caused. Modern computed tomography is producing pictures of high quality, which are highly sufficient for neurosurgical intervention. Very rarely additional angiography has to be performed. The diagnosis of intracranial tumors can fully be established by computed tomography, whereas ventriculography is no longer necessary. (orig.) [de

  10. 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.

  11. Dose optimization in computed tomography: ICRP 87

    International Nuclear Information System (INIS)

    2007-01-01

    The doses given in the use of computed tomography scans are studied, aiming to calibrate the limits of irradiation in patients who need these tests. Furthermore, a good value of computed tomography should be guaranteed by physicians and radiologists for people not being irradiated unfairly, reducing doses and unnecessary tests. A critical evaluation by an ethics committee is suggested for cases where the test is performed for medical research without a cause [es

  12. Quantitative computed tomography evaluation of pulmonary disease

    DEFF Research Database (Denmark)

    McEvoy, Fintan; Buelund, Lene Elisabeth; Strathe, Anders Bjerring

    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....

  13. 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.

  14. Development of emission computed tomography in Japan

    International Nuclear Information System (INIS)

    Tanaka, E.

    1984-01-01

    Two positron emission computed tomography (PCT) devices developed in Japan are described. One is for head and the other for wholebody. The devices show fairly quantitative images with slight modifications of the existing algorithms because they were developed based on filtered back-projection. The PCT device seems to be better than the single photon emission computed tomography (SPECT) since it provides adequade compensation for photon attenuation in patients. (M.A.C.) [pt

  15. Computed tomography of intraventricular hemorrhage

    International Nuclear Information System (INIS)

    Cho, Bum Shin; Shin, Kyoung Hee; Hahm, Chang Kok

    1982-01-01

    Computed tomography (CT) is a new non-invasive diagnostic imaging method, which has ability to differentiate C.S.F., hematoma, and even edematous brain from normal brain tissue. Prior to the introduction of the CT, the diagnosis of the intraventricular hemorrhage in living patients was difficult and was confirmed by surgery of autopsy. Intracranial hemorrhages are visible on the CT with density higher than brain tissue in acute phase. CT is an accurate method for detecting of intraventricular hemorrhage including detection of nature, location, amount, and associated changes. CT is also useful as a guidance and in the evaluation of fate of the hematomas by easily performable follow up studies. The causes of the intraventricular hemorrhages are hypertension, rupture of aneurysm, arteriovenous malformation, head trauma, brain tumor, and others. This study included evaluation of CT of 69 patients who show the high density in cerebral ventricular system during the period of 31 months from Feb. 1979 to Aug. 1981 in the Department of Radiology, College of Medicine, Hanyang University. The results were as follows. 1. Age distribution of the total 69 patient was broad ranging from 1 month to 80 years. 28% of patients were in the 6th decade. The mate to female ratio was 2 : 1. 2. The consciousness of patients at CT study: Those were conscious in 11 cases, stuporous in 41 cases and unconscious in 17 cases. 3. The causes of intraventricular hemorrhages were hypertension in 28 cases, head trauma in 12 cases, aneurysm in 4 cases, tumor in 2 cases and others in 23 cases. 4. 9 cases showed intraventricular hematomas only, other 60 cases showed associated intracranial hematomas: Those were intracerebral hematomas in 53 cases including 30 cases of basal ganglial and thalamic hematomas, subarachnoid hemorrhage in 17 cases, epidural hematomas in 3 cases, and subdural hematomas in 2 cases. 5. All cases of the intraventricular hematomas except one sowed hematoma in the lateral

  16. Computed tomography in subarachnoid hemorrhage

    International Nuclear Information System (INIS)

    Lee, Seung Ro; Chang, Kee Hyun; Choi, Byung Ihn; Han, Man Chung; Sim, Bo Sung

    1981-01-01

    Computed Tomography has become increasingly important diagnostic method as the initial examination in the diagnosis of subarachnoid hemorrhage with direct detection of extravasated blood in basal cistern and cortical sulci. Furthermore, CT provides better and exact visualization of the presence, localization, extent and degree of intracerebral, intraventricular and subdural hemorrhage, infarction, hydrocephalus and rebleeding which may be associated with subarachnoid hemorrhage, and also could detect the causative lesions with contrast enhancement in many cases. The purpose of the paper is to describe the CT findings of subarachnoid hemorrhage due to various causes and to evaluate the diagnostic accuracy of CT in subarachnoid hemorrhage. Authors analysed a total of 153 cases with subarachnoid hemorrhage confirmed by lumbar puncture at Seoul National University Hospital from March 1979 to April 1981, with special emphasis on CT findings. All of the cases took CT scan and 125 cases of them angiography. The results are as follows: 1. Most prevalent age group was 4th to 6th decades (78%). The ratio of male to female was 1.1: 1. 2. Of 125 cases with angiography, aneurysm was a major cause (68%). Others were arterio-venous malformation (9.6%), Moya-moya disease (4%) and unknown (18.4%). 3. Of all 153 cases with CT scan, hemorrhage was demonstrated in 98 cases (64.1%); SAH in 72 cases (47.1%), ICH in 65 cases (42.5%), IVH in 34 cases (22.2%) and SDH in 1 case (0.7%). SAH combined with ICH was a major group (34.7%) in SAH. Detection rate of SAH was 68.3% within the first 7 days and 5.8% after 7 dyas. 4. In aneurysms, SAH was detected in 60 of 85 cases (70.6%); 88.1% within the first 7 dyas and 5.6% after 7 dyas. Anterior communicating artery was the most common site of the aneurysms (40%), in which detection rate of SAH was 100% within the first 7 days. SAH was combined with ICH in 38.3%. 5. On CT, SAH of unilateral Sylvian fissure was pathognomonic for ruptured MCA

  17. 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.

  18. Positron emission tomography/computed tomography scanning for ...

    African Journals Online (AJOL)

    Background: Although the site of nosocomial sepsis in the critically ill ventilated patient is usually identifiable, it may remain occult, despite numerous investigations. The rapid results and precise anatomical location of the septic source using positron emission tomography (PET) scanning, in combination with computed ...

  19. Usefulness of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI): Assessment of morphology and diameter of the superior mesenteric artery (SMA) on multi-planar reconstructed (MPR) images

    International Nuclear Information System (INIS)

    Woodhams, Reiko; Nishimaki, Hiroshi; Fujii, Kaoru; Kakita, Satoko; Hayakawa, Kazushige

    2010-01-01

    Objective: The purpose of this study was to assess the efficacy of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI) by analyzing morphology and diameter of superior mesenteric artery (SMA). We assessed whether MDCT was as useful as angiography for the diagnosis of NOMI. Materials and methods: Four patients who were diagnosed with NOMI were retrospectively analyzed. All patients had 8-row MDCT followed by laparotomy. Two of them underwent angiography after MDCT. The morphology and diameter of SMA of these cases was analyzed on multi-planar reconstructed (MPR) images. The mean diameter of SMA of NOMI cases was compared to that of 13 control cases. Results: MPR images of all NOMI cases showed irregular narrowing of the SMA, spasm of the arcades of SMA, and poor demonstration of intramural vessels. MPR images of two patients who had angiography were concordant with their angiograms. The mean diameter of SMA of NOMI patients was 3.4 ± 1.1 mm, which was statistically smaller than that of 13 control patients, 6.0 ± 1.5 mm (P < 0.05, Wilcoxon rank sum tests). Conclusion: Angiography has been recognized essential for the diagnosis of NOMI. This study shows the possibility of MDCT to be an equivalently useful modality compared to angiography for the diagnosis of NOMI by interpreting morphologic appearance and diameter of SMA. Introduction of MDCT in the decision tree of NOMI treatment may bring the benefit of prompt diagnosis and subsequent early and efficient initiation of therapy, which may improve the mortality.

  20. The Incidence and Anatomy of Accessory Pudendal Arteries as Depicted on Multidetector-Row CT Angiography: Clinical Implications of Preoperative Evaluation for Laparoscopic and Robot-Assisted Radical Prostatectomy

    International Nuclear Information System (INIS)

    Park, Beom Jin; Sung, Deuk Jae; Kim, Min Ju; Cho, Sung Bum; Kim, Yun Hwan; Chung, Kyoo Byung; Kang, Seok Ho; Cheon, Jun

    2009-01-01

    To help preserve accessory pudendal arteries (APAs) and to ensure optimal postoperative sexual function after a laparoscopic or robot-assisted radical prostatectomy, we have evaluated the incidence of APAs as detected on multidetector-row CT (MDCT) angiography and have provided a detailed anatomical description. The distribution of APAs was evaluated in 121 consecutive male patients between February 2006 and July 2007 who underwent 64- channel MDCT angiography of the lower extremities. We defined an APA as any artery located within the periprostatic region running parallel to the dorsal vascular complex. We also subclassified APAs into lateral and apical APAs. Two radiologists retrospectively evaluated the origin, course and number of APAs; the final APA subclassification based on MDCT angiography source data was determined by consensus. We identified 44 APAs in 36 of 121 patients (30%). Two distinct varieties of APAs were identified. Thirty-three APAs (75%) coursed near the anterolateral region of the prostatic apex, termed apical APAs. The remaining 11 APAs (25%) coursed along the lateral aspect of the prostate, termed lateral APAs. All APAs originated from the internal obturator artery and iliac artery or a branch of the iliac artery such as the inferior vesical artery. The majority of apical APAs arose from the internal obturator artery (84%). Seven patients (19%) had multiple APAs. APAs are more frequently detected by the use of MDCT angiography than as suggested by previous surgical studies. The identification of APAs on MDCT angiography may provide useful information for the surgical preservation of APAs during a laparoscopic or robot-assisted radical prostatectomy

  1. Computed tomography of cartilaginous tumours

    International Nuclear Information System (INIS)

    Marincek, B.; Triller, J.; Robotti, G.; Gumppenberg, S. von

    1984-01-01

    The compound tomography (CT) morphology of cartilaginous tumors and the utility of CT in their diagnostic work-up is presented on the basis of 19 cases. CT provided unique informations regarding definition of tumor extent and tumor relationship to adjacent structures particularly in the axial skeleton. CT has diminished the indications for angiography in cartilaginous tumors. (orig.) [de

  2. 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 ...

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

    Medline Plus

    Full Text Available ... which rotates around the patient. The computer that processes the imaging information and monitor are located in ... follows a spiral path. A special computer program processes this series of pictures, or slices of the ...

  4. Computer axial tomography in geosciences

    International Nuclear Information System (INIS)

    Duliu, Octavian G.

    2002-01-01

    Computer Axial Tomography (CAT) is one of the most adequate non-invasive techniques for the investigation of the internal structure of a large category of objects. Initially designed for medical investigations, this technique, based on the attenuation of X- or gamma-ray (and in some cases neutrons), generates digital images which map the numerical values of the linear attenuation coefficient of a section or of the entire volume of the investigated sample. Shortly after its application in medicine, CAT has been successfully used in archaeology, life sciences, and geosciences as well as for the industrial materials non-destructive testing. Depending on the energy of the utilized radiation as well as on the effective atomic number of the sample, CAT can provide with a spatial resolution of 0.01 - 0.5 mm, quantitative as well as qualitative information concerning local density, porosity or chemical composition of the sample. At present two types of axial Computer Tomographs (CT) are in use. One category, consisting of medical as well as industrial CT is equipped with X-ray tubes while the other uses isotopic gamma-ray sources. CT provided with intense X-ray sources (equivalent to 12-15 kCi or 450-550 TBq) has the advantage of an extremely short running time (a few seconds and even less) but presents some disadvantages known as beam hardening and absorption edge effects. These effects, intrinsically related to the polychromatic nature of the X-rays generated by classical tubes, need special mathematical or physical corrections. A polychromatic X-ray beam can be made almost monochromatic by means of crystal diffraction or by using adequate multicomponent filters, but these devices are costly and considerably diminish the output of X-ray generators. In the case of CT of the second type, monochromatic gamma-rays generated by radioisotopic sources, such as 169 Yb (50.4 keV), 241 Am (59 keV), 192 Ir (310.5 and 469.1 keV ) or 137 Cs (662.7 keV), are used in combination with

  5. Indication for dental computed tomography. Case reports

    International Nuclear Information System (INIS)

    Schom, C.; Engelke, W.; Kopka, L.; Fischer, U.; Grabbe, E.

    1996-01-01

    Based on case reports, common indications for dental computed tomography are demonstrated and typical findings are analysed. From a group of 110 patients who had a reformatted computed tomography of the maxilla and mandibula, 10 typical cases were chosen as examples and are presented with a detailed description of the findings. The most important indication was the analysis of the morphology of the alveolar ridge needed in presurgical planning for osseointegrated implants as well as in special cases of postsurgical control. Apart from implantology, the method could be used in cases of mandibular cysts and bony destructions. In conclusion, dental computed tomography has become established mainly in implantology. It can provide valuable results in cases where a demonstration of the bone in all dimensions and free of overlappings and distortions is needed. (orig.) [de

  6. Computed tomography in malignant primary bone tumours

    International Nuclear Information System (INIS)

    Kersjes, W.; Harder, T.; Haeffner, P.

    1990-01-01

    The importance of computed tomography is examined in malignant primary bone tumours using a strongly defined examination group of 13 Patients (six Ewing's-sarcomas, five osteosarcomas, one chondrosarcoma and one spindle-shaped cell sarcoma). Computed tomography is judged superior compared to plain radiographs in recognition of bone marrow infiltration and presentation of parosteal tumour parts as well as in analysis of tissue components of tumours, CT is especially suitable for therapy planning and evaluating response to therapy. CT does not provide sufficient diagnostic information to determine dignity and exact diagnosis of bone tumours. (orig.) [de

  7. Computed tomography of sacro-iliac joints

    International Nuclear Information System (INIS)

    Miquel, A.; Laredo, J.D.

    1995-01-01

    Actual technologies to explore sacro-iliac joints are conventional radiography, computed tomography , scintigraphy and nuclear magnetic resonance imaging. Standards films are sufficient, except in beginning sacro-iliac septic inflammations where the computed tomography is superior. Two problems are generally posed for the radiologist, to differentiate a septic arthritis from a rheumatic pathology An other problem in diagnosis is to make the difference between a degenerative arthropathy (which does not need a further investigation) and an infectious rheumatic pathology where more exploration is necessary. 28 refs., 3 tabs., 13 figs

  8. The Western Denmark Cardiac Computed Tomography Registry

    DEFF Research Database (Denmark)

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

    2014-01-01

    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...... examined the content, data quality, and research potential of the WDHR-CCTR. METHODS: We retrieved 2008-2012 data to examine the 1) content; 2) completeness of procedure registration using the Danish National Patient Registry as reference; 3) completeness of variable registration comparing observed vs...

  9. 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...... 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-to-intermediate pretest...

  10. Physics of x-ray computed tomography

    International Nuclear Information System (INIS)

    Akutagawa, W.M.; Huth, G.C.

    1976-01-01

    Sections are included on theoretical limits of x-ray computed tomography and the relationship of these limits to human organ imaging and specific disease diagnosis; potential of x-ray computed tomography in detection of small calcified particles in early breast cancer detection; early lung cancer measurement and detection; advanced materials for ionizing radiation detection; positron system with circular ring transaxial tomographic camera; contrast mechanism of transmission scanner and algorithms; and status of design on a 200 keV scanning proton microprobe

  11. Computed tomography in dementia of Alzheimer type

    International Nuclear Information System (INIS)

    Tsunoda, Masahiko; Fujii, Tsutomu; Tanii, Yasuyuki

    1990-01-01

    Computed tomography (CT) examinations of 7 patients with dementia of Alzheimer type were reviewed and correlated with clinical stages. The findings of CT were also compared with those of single photon emission computed tomography (SPECT). There was no positive correlation between the degree of cerebral atrophy on CT and clinical stage. Cerebral atrophy seemed to be influenced by aging, ill duration, and the degree of dementia. The cerebral/cerebellar uptake ratio of RI on SPECT was significantly decreased with the progression of clinical stage. SPECT seemed to reflect the degree of dementia, irrespective of ages and ill duration. (N.K.)

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

    Medline Plus

    Full Text Available ... so that the x-ray beam follows a spiral path. A special computer program processes this series ... Sometimes ultrasound is substituted for CT as a method of imaging in these procedures in children. A ...

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

    Medline Plus

    Full Text Available ... planes, and can even generate three-dimensional images. These images can be viewed on a computer monitor, ... diabetes, kidney disease or thyroid problems. Any of these conditions may influence the decision on whether contrast ...

  14. 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 ...

  15. 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 DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail ...

  16. 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 ...

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

    International Nuclear Information System (INIS)

    Delalu, P.; Ferretti, G.R.; Bricault, I.; Ayanian, D.; Coulomb, M.

    2000-01-01

    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.)

  18. Computed Tomography Study Of Complicated Bacterial Meningitis ...

    African Journals Online (AJOL)

    To monitor the structural intracranial complications of bacterial meningitis using computed tomography (CT) scan. Retrospective study of medical and radiological records of patients who underwent CT scan over a 4 year period. AUniversityTeachingHospital in a developing country. Thirty three patients with clinically and ...

  19. Computed tomography - old ideas and new technology

    Energy Technology Data Exchange (ETDEWEB)

    Fleischmann, Dominik; Boas, F.E. [Stanford University, School of Medicine, Department of Radiology, Stanford, CA (United States)

    2011-03-15

    Several recently introduced 'new' techniques in computed tomography - iterative reconstruction, gated cardiac CT, multiple-source, and dual-energy CT - actually date back to the early days of CT. We review the historic origins and evolution of these techniques, which may provide some insight into the latest innovations in commercial CT systems. (orig.)

  20. Computed tomography in the evaluation of trauma

    International Nuclear Information System (INIS)

    Federle, M.P.; Brant-Zawadzki, M.

    1982-01-01

    This book is intended to be the current standard for computed tomography in the evaluation of trauma. It summarizes two years of experience at San Francisco General Hospital. The book is organized into seven chapters, covering head, maxillofacial, laryngeal, spinal, chest, abdominal, acetabular, and pelvic trauma. Extremity trauma is not discussed

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

    International Nuclear Information System (INIS)

    Santos, M.B. dos; Luca, V. de; Ferreira, M.A.S.; Barros, A.P. de

    1982-01-01

    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. (Author) [pt

  2. Computed tomography evaluation of petrous bone fractures ...

    African Journals Online (AJOL)

    Background: Petrous bone trauma is the sequel of blunt head injury and can have life threatening complications resulting in immediate mortality. Early detection and good knowledge of the Computed Tomography (CT) findings ensure prompt treatment of both fractures and complications. Objective: To document the ...

  3. Appropriateness of computed tomography and magnetic resonance ...

    African Journals Online (AJOL)

    Introduction. Computed tomography (CT) and magnetic resonance imaging (MRI) are an essential part of modern healthcare. Marked increases in clinical demand for these imaging modalities are straining healthcare expenditure and threatening health system sustainability. The number of CT and MRI scans requested in ...

  4. 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...

  5. 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...

  6. Computed tomography of intussusception in adult

    International Nuclear Information System (INIS)

    Jeon, Hae Jeong; Ahn, Byeong Yeob; Cha, Soon Joo; Seol, Hae Young; Chung, Kyoo Byung; Suh, Won Hyuck

    1984-01-01

    Intussusception is rare in adult and usually caused by organic lesions, although there is a significant number of so-called idiopathic cases. The diagnosis of intussusception have been made by plain abdomen, barium enema and small bowel series. But recently ultrasound and computed tomography make a contribution to diagnose intussusception. Computed tomography is not the primary means for evaluating a gastrointestinal tract abnormality but also provides valuable information in evaluating disorders affecting the hollow viscera of the alimentary tract. Computed tomography image of intussusception demonstrates a whirl like pattern of bowel loops separated by fatty stripe correlating of the intestinal walls. Abdominal ultrasonogram was used as the initial diagnostic test in 2 cases out of total 4 cases, with abdominal mass of unknown cause. It revealed a typical pattern, composed of a round or oval mass with central dense echoes and peripheral poor echoes. We report 4 all cases of intussusception in adult who were performed by computed tomography and/or ultrasound. All cases were correlated with barium enema examination and/or surgical reports.

  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...

  8. 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...

  9. 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...

  10. Investigation of measuring strategies in computed tomography

    DEFF Research Database (Denmark)

    Müller, Pavel; Hiller, Jochen; Cantatore, Angela

    2011-01-01

    Computed tomography has entered the industrial world in 1980’s as a technique for non-destructive testing and has nowadays become a revolutionary tool for dimensional metrology, suitable for actual/nominal comparison and verification of geometrical and dimensional tolerances. This paper evaluates...

  11. Computed tomography in severe protein energy malnutrition.

    OpenAIRE

    Househam, K C; de Villiers, J F

    1987-01-01

    Computed tomography of the brain was performed on eight children aged 1 to 4 years with severe protein energy malnutrition. Clinical features typical of kwashiorkor were present in all the children studied. Severe cerebral atrophy or brain shrinkage according to standard radiological criteria was present in every case. The findings of this study suggest considerable cerebral insult associated with severe protein energy malnutrition.

  12. Computed tomography of the iliopsoas muscle

    International Nuclear Information System (INIS)

    Nino-Murcia, M.; Wechsler, R.J.; Brennan, R.E.

    1983-01-01

    Computed tomography (CT) is an ideal method for the imaging of the psoas muscle. The authors present 13 cases of patients with psoas abnormalities diagnosed by CT. The CT features of the different pathologic entities and comparison of CT with other imaging modalities are discussed. (orig.)

  13. 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

  14. Computed tomography of tuberculous meningitis

    International Nuclear Information System (INIS)

    Sato, Noriko; Sato, Hiromi; Kawaguchi, Tetsuro; Fujita, Katsuzo; Tanaka, Makoto

    1982-01-01

    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. (author)

  15. Misty mesentery: computed tomography findings

    International Nuclear Information System (INIS)

    Ahualli, Jorge; Mendez Uriburu, Luis; Ravera, Maria L.; Cikman, Pablo

    2008-01-01

    An alteration in the density of the mesenteric adipose tissue is often the principal clue of underlying mesenteric and bowel disease. The term 'Misty Mesentery' describes the computed tomographic appearance of mesenteric fat infiltrated by inflammatory cells, fluid (edema, lymph, and/or blood), tumor, and fibrosis. (author) [es

  16. 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 About Us News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed ...

  17. 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 ...

  18. Computed Tomography in Forensic Medicine

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    2015-01-01

    was not used. Autopsies were performed according to the Danish government's official guidelines. PMCT and autopsy findings were interpreted independent of each other. Diagnoses, including the cause of death and histology findings, were registered in a computer database (SPSS) together with information about...

  19. Computed tomography in Alexander's disease

    Energy Technology Data Exchange (ETDEWEB)

    Holland, I M; Kendall, B E

    1980-10-01

    Two cases of biopsy-proven Alexander's disease are described with computed tomographic changes which, in our experience and on survey of the literature, have not occurred in any other condition. Such changes in a child with a progressive condition consistent with Alexander's disease, strongly support the diagnosis.

  20. Computed tomography of limy bile

    International Nuclear Information System (INIS)

    Yamamoto, Shinichiro; Kimoto, Masatoshi; Gunge, Nobuharu; Sano, Kaizo; Yamashita, Sachiko; Hirano, Yutaka

    1983-01-01

    The computed tomographic appearance of three cases of limy bile was reported. The CT findings consist of uniform high density within gallbladder, niveau formation between limy bile and noncalcified bile. Sagittal reconstruction of CT images was especially useful in the differentiation of limy bile and gallstones. (author)

  1. Thermoluminescent dosimetry in computed tomography

    International Nuclear Information System (INIS)

    Lara C, A.; Rivera M, T.; Osorio V, M.; Hernandez O, O.

    2016-10-01

    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)

  2. 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)

  3. Cerebral candidiasis. Computed tomography appearance

    International Nuclear Information System (INIS)

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

    1989-01-01

    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.)

  4. 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.).

  5. Microfocus computed tomography in medicine

    Science.gov (United States)

    Obodovskiy, A. V.

    2018-02-01

    Recent advances in the field of high-frequency power schemes for X-ray devices allow the creation of high-resolution instruments. At the department of electronic devices and Equipment of the St. Petersburg State Electrotechnical University, a model of a microfocus computer tomograph was developed. Used equipment allows to receive projection data with an increase up to 100 times. A distinctive feature of the device is the possibility of implementing various schemes for obtaining projection data.

  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. Computed tomography of thymic abnormalities

    International Nuclear Information System (INIS)

    Schnyder, P.; Candardjis, G.

    1987-01-01

    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. (orig.)

  8. Orbital computed tomography: technical aspects

    International Nuclear Information System (INIS)

    Beck, T.J.; Rosenbaum, A.E.; Miller, N.R.

    1982-01-01

    Computed tomographic scanning has revolutionized the diagnosis and management of orbital disease. The best use of this methodology requires knowledge of the principles and appropriate attention to scanning protocols. Computed tomographic scanning of the orbit is a demanding technique requiring thin sections through planes precisely positioned from the topographical anatomy. Ideally, orbital CT should include both transverse axial and coronal sections: The pathological condition and its plane of growth will influence the selection of the optimal plane or section. Coronal sections may be obtained either directly or indirectly by computer reconstruction from contiguous transverse images. Sagittal or oblique sections or both also are useful and may be obtained directly or indirectly. Difficulty in patient positioning may preclude direct sagittal imaging, however. The use of intravenous contrast enhancement is not necessary as a routine technique unless a mass is identified or suspected. Where surgical resection or biopsy of a space-occupying lesion is contemplated, contrast enhancement can be valuable in assessing relative vascularity and aiding diagnostic specificity. It should be continually emphasized that CT is a powerful technology which, in orbital diagnosis, produces the highest yield when clinician and radiologist collaborate in the radiodiagnostic workup. The clinical information supplied by the referring ophthalmologist is used by the radiologist both in the selection of the appropriate techniques for investigation and in striving to achieve the most specific conclusion

  9. Proton computed tomography images with algebraic reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Bruzzi, M. [Physics and Astronomy Department, University of Florence, Florence (Italy); Civinini, C.; Scaringella, M. [INFN - Florence Division, Florence (Italy); Bonanno, D. [INFN - Catania Division, Catania (Italy); Brianzi, M. [INFN - Florence Division, Florence (Italy); Carpinelli, M. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Chemistry and Pharmacy Department, University of Sassari, Sassari (Italy); Cirrone, G.A.P.; Cuttone, G. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Presti, D. Lo [INFN - Catania Division, Catania (Italy); Physics and Astronomy Department, University of Catania, Catania (Italy); Maccioni, G. [INFN – Cagliari Division, Cagliari (Italy); Pallotta, S. [INFN - Florence Division, Florence (Italy); Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Florence (Italy); SOD Fisica Medica, Azienda Ospedaliero-Universitaria Careggi, Firenze (Italy); Randazzo, N. [INFN - Catania Division, Catania (Italy); Romano, F. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Sipala, V. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Chemistry and Pharmacy Department, University of Sassari, Sassari (Italy); Talamonti, C. [INFN - Florence Division, Florence (Italy); Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Florence (Italy); SOD Fisica Medica, Azienda Ospedaliero-Universitaria Careggi, Firenze (Italy); Vanzi, E. [Fisica Sanitaria, Azienda Ospedaliero-Universitaria Senese, Siena (Italy)

    2017-02-11

    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 <1 mm, achieved within processing times of ~15′ for a 512×512 pixels image prove that this technique will be beneficial if used instead of X-CT in hadron-therapy.

  10. Measuring techniques in emission computed tomography

    International Nuclear Information System (INIS)

    Jordan, K.; Knoop, B.

    1988-01-01

    The chapter reviews the historical development of the emission computed tomography and its basic principles, proceeds to SPECT and PET, special techniques of emission tomography, and concludes with a comprehensive discussion of the mathematical fundamentals of the reconstruction and the quantitative activity determination in vivo, dealing with radon transformation and the projection slice theorem, methods of image reconstruction such as analytical and algebraic methods, limiting conditions in real systems such as limited number of measured data, noise enhancement, absorption, stray radiation, and random coincidence. (orig./HP) With 111 figs., 6 tabs [de

  11. Computed tomography of the skeletal system

    International Nuclear Information System (INIS)

    Maas, R.; Heller, M.

    1990-01-01

    Patients showing severe multiple injuries, require special care and attention in the hospital. In these cases, the range of the diagnostic measures taken subsequent to computed tomography of the cranium must be broadened to include examinations of the vertebral column and pelvic ring for traumatic lesions. Radiological routine procedures are discussed wit hthe view of throwing some light on the problems involved incomputed tomography of the vertebral disks. In degenerative processes associated with spinal stenosis and hypertrophic facets it has been found that angular-sagittal-reconstruction may be quite useful. Computed tomography provides valuable information on morphological factors and has great discriminating power in the diagnosis of skeletal tumours of the extremities. Quantitative computed tomography offers unprecedented possibilities in the diagnosis and treatment of osteoporosis. Here, particular care must be taken to avoid inaccuracies of measurement as a result of incorrectly performed examinations. In malignant bone tumours the method of dynamic scanning permits the success or failure of any radiotherapeutic or chemical measures taken to be evaluated at an early stage. The success or failure of any radiotherapeutic or chemical measures taken to to treat malignant bone tumours can be evaluated at an early stage using the method on dynamic scanning. (orig.) [de

  12. Comparison between conventional tomography and computer tomography in diseases of the sacroiliac joints

    International Nuclear Information System (INIS)

    Moritz, J.D.; Ganter, H.; Winter, C.; Evangelisches Krankenhaus, Giessen

    1990-01-01

    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.) [de

  13. Computed tomography in diagnostics of effluent otitis media

    International Nuclear Information System (INIS)

    Imomova, L.S.; Norboev, Z.; Kalandarov, S.Ch.

    2011-01-01

    This article is devoted to computed tomography in diagnostics of effluent otitis media. The purpose of present work is to assess the possibilities of computed tomography method of temporal bone in the diagnostics of otitis media.

  14. Computed tomography of the menisci

    International Nuclear Information System (INIS)

    Wagner-Manslau, C.; Rupp, N.; Paar, O.; Rodammer, G.

    1988-01-01

    Thirty patients were examined with CT of the menisci. All findings were confirmed by arthroscopy. One false positive diagnosis of a torn meniscus was made, caused by partial volume effect. In seven patients with irregular degenerative changes of the menisci, the abnormality could be clearly demonstrated. One meniscus ganglion was shown. Seven meniscus lesions, which were not shown by arthrography or arthroscopy, were clearly demonstrated by CT. The computer tomographic demonstration of menisci can replace knee arthrography as the examination of choice and should be performed before carrying out arthroscopy. (orig.) [de

  15. 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.

  16. Computed tomography of tibial plateau fractures

    International Nuclear Information System (INIS)

    Rafii, M.; Firooznia, H.; Golimbu, C.; Bonamo, J.

    1984-01-01

    Twenty patients with tibial plateau fractures were studied by conventional tomography and computed tomography (CT) in order to determine the role and feasibility of CT in management of such patients. CT resulted in less discomfort to the patient and provided optimal visualization of the plateau defect and the split fragments. It proved more accurate than conventional tomography in assessing depressed and split fractures when they involved the anterior or posterior border of the plateau and in demonstrating the extent of fracture comminution. Split fragments with an oblique plane of fracture also were seen better by CT. The degree of fracture depression and separation as measured by the computerized technique was often more accurate than measurements obtained from conventional tomograms

  17. 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...... applications. This thesis takes a systematic approach toward establishing quantitative understanding of conditions for sparse reconstruction to work well in CT. A general framework for analyzing sparse reconstruction methods in CT is introduced and two sets of computational tools are proposed: 1...... contributions to a general set of computational characterization tools. Thus, the thesis contributions help advance sparse reconstruction methods toward routine use in...

  18. Computed tomography of pelvic fractures

    Energy Technology Data Exchange (ETDEWEB)

    Kimoto, Makoto; Hashimoto, Keiji; Hiraki, Yoshio

    1984-12-01

    Plain x-ray and computed tomographic (CT) findings were compared in 7 patients with pelvic fractures (2 males and 5 females) aged between 35 and 50 year. Plain x-rays had a higher sensitivity than CT in detecting fractures of the ischiatic and pubic ramuses, and deviation of bone fragments. CT was superior to plain x-rays near the acetabulum and in detecting deviation of bone fragments. Although there were no differences between the two modalities in detecting fractures of the wing of ilium, CT was more useful than plain x-rays in visualizing deviation of bone fragments. CT clearly visualized not only fractures but also injuries of the soft tissues, such as pelvic viscera and muscles, and the presence of hematoma. CT seems to be a useful method for observing the condition and process of pelvic injuries and for deciding treatment protocols.

  19. Pitfalls in multidetector row CT colonography

    International Nuclear Information System (INIS)

    Stoyneva, V.

    2009-01-01

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

  20. 21 CFR 892.1200 - Emission computed tomography system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Emission computed tomography system. 892.1200... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1200 Emission computed tomography system. (a) Identification. An emission computed tomography system is a device intended to detect the...

  1. Cone beam computed tomography in endodontic

    Energy Technology Data Exchange (ETDEWEB)

    Durack, Conor; Patel, Shanon [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)

  2. Cone beam computed tomography in endodontic

    International Nuclear Information System (INIS)

    Durack, Conor; Patel, Shanon

    2012-01-01

    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)

  3. Emission computed tomography: methodology and applications

    International Nuclear Information System (INIS)

    Reivich, M.; Alavi, A.; Greenberg, J.; Fowler, J.; Christman, D.; Rosenquist, A.; Rintelmann, W.; Hand, P.; MacGregor, R.; Wolf, A.

    1980-01-01

    A technique for the determination of local cerebral glucose metabolism using positron emission computed tomography is described as an example of the development of use of this methodology for the study of these parameters in man. The method for the determination of local cerebral glucose metabolism utilizes 18 F-2-fluoro-2-deoxyglucose ([ 18 F]-FDG). In this method [ 18 F]-FDG is used as a tracer for the exchange of glucose between plasma and brain and its phosphorylation by hexokinase in the tissue. The labelled product of metabolism, [ 18 F]-FDG phosphate, is essentially trapped in the tissue over the time course of the measurement. The studies demonstrate the potential usefulness of emission computed tomography for the measurement of various biochemical and physiological parameters in man. (Auth.)

  4. Computed tomography of chest wall abscess

    International Nuclear Information System (INIS)

    Ikezoe, Junpei; Morimoto, Shizuo; Akira, Masanori

    1986-01-01

    Inflammatory lesions of the chest wall become less common because of the improvement of antibiotics and chemotherapeutic agents. Over a 5-year period, 7 patients with chest wall inflammatory diseases underwent chest computed tomography. These were 2 tuberculous pericostal abscesses, 2 empyema necessitatis, 1 spinal caries, and 2 bacterial chest wall abscesses (unknown organisms). Computed tomography (CT) helped in demonstrating the density, border, site, and extent of the lesions. CT images also demonstrated the accompaning abnormalities which included bone changes, pleural calcification, or old tuberculous changes of the lung. CT was very effective to demonstrate the communicating portions from the inside of the bony thorax to the outside of the bony thorax in 2 empyema necessitatis. (author)

  5. Soil structure changes evaluated with computed tomography

    International Nuclear Information System (INIS)

    Pires, Luiz Fernando

    2010-01-01

    The objective of this work was to evaluate in millimetric scale changes in soil bulk density and porosity, using the gamma-ray computed tomography in soil samples with disturbed structure due to wetting and drying (W-D) cycles. Soil samples with 98.1 cm 3 were sieved using a 2 mm mesh and homogeneously packed in PVC cylinders. Soil samples were submitted to 1, 2, and 3 W-D cycles. Control samples were not submitted to W-D cycles. After repetitions of W-D cycles, soil sample porosity decreased and soil layers became denser. Computed tomography allowed a continuous analysis of soil bulk density and also soil porosity along millimetric (0.08 cm) layers, what cannot be provided by traditional methods used in soil physics. (author)

  6. Possibilities of computer tomography in multiple sclerosis

    International Nuclear Information System (INIS)

    Vymazal, J.; Bauer, J.

    1983-01-01

    Computer tomography was performed in 41 patients with multiple sclerosis, the average age of patients being 40.8 years. Native examinations were made of 17 patients, examinations with contrast medium of 19, both methods were used in the examination of 5 patients. In 26 patients, i.e. in almost two-thirds, cerebral atrophy was found, in 11 of a severe type. In 9 patients atrophy affected only the hemispheres, in 16 also the stem and cerebellum. The stem and cerebellum only were affected in 1 patient. Hypodense foci were found in 21 patients, i.e. more than half of those examined. In 9 there were multiple foci. In most of the 19 examined patients the hypodense changes were in the hemispheres and only in 2 in the cerebellum and brain stem. No hyperdense changes were detected. The value and possibilities are discussed of examinations by computer tomography multiple sclerosis. (author)

  7. Basic principle of cone beam computed tomography

    International Nuclear Information System (INIS)

    Choi, Yong Suk; Kim, Gyu Tae; Hwang, Eui Hwan

    2006-01-01

    The use of computed tomography for dental procedures has increased recently. Cone beam computed tomography(CBCT) systems have been designed for imaging hard tissues of the dentomaxillofacial region. CBCT is capable of providing high resolution in images of high diagnostic quality. This technology allows for 3-dimensional representation of the dentomaxillofacial skeleton with minimal distortion, but at lower equipment cost, simpler image acquisition and lower patient dose. Because this technology produces images with isotropic sub-millimeter spatial resolution, it is ideally suited for dedicated dentomaxillofacial imaging. In this paper, we provide a brief overview of cone beam scanning technology and compare it with the fan beam scanning used in conventional CT and the basic principles of currently available CBCT systems

  8. 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.

  9. Xenon as an adjunct in computed tomography

    International Nuclear Information System (INIS)

    Kendall, B.E.; Radue, E.W.; Zilkha, E.; Loh, L.

    1979-01-01

    Nonradioactive xenon was used for enhancement in computed tomography in a series of 18 patients requiring general anesthesia. The method and results are described. The properties of xenon are radically different from those of intravenous iodides, and the enhancement patterns demonstrate different aspects of both normal and abnormal tissues. In our limited experience, it has been of value in those isodense and low attenuation lesions that have not enhanced after intravenous Conray. (orig.) 891 MG/orig. 892 MB [de

  10. Computed tomography of the eye and orbit

    International Nuclear Information System (INIS)

    Hammerschlag, S.B.; Hesselink, J.R.; Weber, A.L.

    1982-01-01

    This book is the product of the evolution of computed tomography (CT) into subspecialization and the need for one source of information for the busy radiologist. The authors have succeeded in providing a readable overview of orbital CT as well as a reference book. The book is divided into seven major catagories of pathology (Neurofibromatosis, Primary Orbital Neoplasms, Secondary and Metastic Tumors of the Orbit, Vascular Disorders, Inflammatory Disease, Occular Lesions, and Trauma) after separate discussions of anatomy and technique

  11. Computed tomography in gastrointestinal stromal tumors

    International Nuclear Information System (INIS)

    Ghanem, Nadir; Altehoefer, Carsten; Winterer, Jan; Schaefer, Oliver; Springer, Oliver; Kotter, Elmar; Langer, Mathias; Furtwaengler, Alex

    2003-01-01

    The aim of this study was to define the imaging characteristics of primary and recurrent gastrointestinal stromal tumors (GIST) in computed tomography with respect to the tumor size. Computed tomography was performed in 35 patients with histologically confirmed gastrointestinal stromal tumors and analyzed retrospectively by two experienced and independent radiologist. The following morphologic tumor characteristics of primary (n=20) and (n=16) recurrent tumors were evaluated according to tumor size, shape, homogeneity, density compared with liver, contrast enhancement, presence of calcifications, ulcerations, fistula or distant metastases and the anatomical relationship to the intestinal wall, and the infiltration of adjacent visceral organs. Small GIST ( 5-10 cm) demonstrated an irregular shape, inhomogeneous density on unenhanced and contrast-enhanced images, a combined intra- and extraluminal tumor growth with aggressive findings, and infiltration of adjacent organs in 9 primary diagnosed and 2 recurrent tumors. Large GIST (>10 cm), which were observed in 8 primary tumors and 11 recurrent tumors, showed an irregular margin with inhomogeneous density and aggressive findings, and were characterized by signs of malignancy such as distant and peritoneal metastases. Small recurrent tumors had a similar appearance as compared with large primary tumors. Computed tomography gives additional information with respect to the relationship of gastrointestinal stromal tumor to the gastrointestinal wall and surrounding organs, and it detects distant metastasis. Primary and recurrent GIST demonstrate characteristic CT imaging features which are related to tumor size. Aggressive findings and signs of malignancy are found in larger tumors and in recurrent disease. Computed tomography is useful in detection and characterization of primary and recurrent tumors with regard to tumor growth pattern, tumor size, and varied appearances of gastrointestinal stromal tumors, and indirectly

  12. Computed tomography in opportunistic lung infections

    International Nuclear Information System (INIS)

    Hartelius, H.

    1988-01-01

    Chest radiography in two teenage boys, one with Wiscott-Aldrich's syndrome and one with acute lymphatic leucemia in remission showed increased interstitial pattern. In both computed tomography (CT) of the lungs showed heavy interstitial pneumonia, rather different in appearance but in both cases equal to the CT findings in opportunistic lung infections known from immunoincompetent patients with for instance pneumocystis carinii and/or cytomegalo virus infections. In both patients the CT findings led to lung biopsy establishing the etiologic agent. (orig.)

  13. Cranial computed tomography of the neurofibromatosis

    International Nuclear Information System (INIS)

    Fukuda, Teruo; Inoue, Yuichi; Shibakiri, Ippei

    1981-01-01

    The computed tomography (CT) was performed in 10 cases of neurofibromatosis. The CT scan showed the abnormal findings in 8 cases out of 10. Skull lesions were noted in 3 cases and intracranial tumors were found in 5 among which multiple neoplasms were seen in 3. Although reported cases were not large enough in number, the incidence and variety of the tumors were similar to others reported before CT era. (author)

  14. Computed tomography manifestations of peritoneal diseases

    International Nuclear Information System (INIS)

    Gordon, K.; Lee, W.K.; Hennessy, O.

    2005-01-01

    The peritoneal cavity is a potential space that is divided by the peritoneal reflections into various complex subspaces. It can be involved in many disease processes including developmental, inflammatory, neoplastic and traumatic conditions. Computed tomography is highly sensitive and consistent in detecting peritoneal pathology. This pictorial essay aims to emphasize and illustrate the CT features of the spectrum of peritoneal diseases. Copyright (2005) Blackwell Science Pty Ltd

  15. 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)

  16. Computed tomography after radical pancreaticoduodenectomy (Whipple's procedure)

    International Nuclear Information System (INIS)

    Smith, S.L.; Hampson, F.; Duxbury, M.; Rae, D.M.; Sinclair, M.T.

    2008-01-01

    Whipple's procedure (radical pancreaticoduodenectomy) is currently the only curative option for patients with periampullary malignancy. The surgery is highly complex and involves multiple anastomoses. Complications are common and can lead to significant postoperative morbidity. Early detection and treatment of complications is vital, and high-quality multidetector computed tomography (MDCT) is currently the best method of investigation. This review outlines the surgical technique and illustrates the range of normal postoperative appearances together with the common complications

  17. Fatty kidney diagnosed by mortem computed tomography

    DEFF Research Database (Denmark)

    Leth, P. M.

    2016-01-01

    Subnuclear vacuolization of the renal tubular epithelium is indicative of diabetic and alcoholic ketoacidosis and has also been proposed as a postmortem marker for hypothermia. We present for the first time a fatal case of ketoacidosis in combination with exposure where a suspicion of these diagn...... of these diagnoses was raised by a marked radiolucency of the kidneys at post-mortem computed tomography (PMCT). © 2015 Elsevier Ltd....

  18. Physics and instrumentation of emission computed tomography

    International Nuclear Information System (INIS)

    Links, J.M.

    1986-01-01

    Transverse emission computed tomography can be divided into two distinct classes: single photon emission computed tomography (SPECT) and positron emission tomography (PET). SPECT is usually accomplished with specially-adapted scintillation cameras, although dedicated SPECT scanners are available. The special SPECT cameras are standard cameras which are mounted on gantries that allow 360 degree rotation around the long axis of the head or body. The camera stops at a number of angles around the body (usually 64-128), acquiring a ''projection'' image at each stop. The data from these projections are used to reconstruct transverse images with a standard ''filtered back-projection'' algorithm, identical to that used in transmission CT. Because the scintillation camera acquires two-dimensional images, a simple 360 degree rotation around the patient results in the acquisition of data for a number of contiguous transverse slices. These slices, once reconstructed, can be ''stacked'' in computer memory, and orthogonal coronal and sagittal slices produced. Additionally, reorienting algorithms allow the generation of slices that are oblique to the long axis of the body

  19. Computed tomography in intracranial malignant lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Naruse, S; Odake, G; Fujimoto, M; Yamaki, T; Mizukawa, N [Kyoto Prefectural Univ. of Medicine (Japan)

    1978-09-01

    Malignant lymphoma of the central nervous system has been found more and more often in recent years, partly because of the increased use of radiation and such drugs as steroids and antibiotics. However, the definite diagnosis of this disease is difficult until histological verification has been done by operation or autopsy. Since the revolutionary development of computed tomography, however, several reports have been presented, on the computed tomography of malignant lymphoma of the thorax and abdomen. Nevertheless, only a few cases of intracranial malignant lymphoma have been reported. The purpose of this paper, using four patients, is to emphasize the value of computed tomography in the diagnosis of intracranial malignant lymphoma. The characteristic CT findings of intracranial malignant lymphoma may be summarized follows: (1) the tumors are demonstrated to be well-defined, nodular-shaped, and homogenous isodensity - or slightly high-density - lesions in plain scans, and the tumors homogenously increase in density upon contrast enhancement; (2) the disease always has multifocal intracranial lesions, which are shown simultaneously or one after another, and (3) perifocal edema is prominent around the tumors in the cerebral hemisphere.

  20. 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......, Technology and Innovation. The comparison aims to collect information about measurement performance in state-of the-art industrial CT (Computed Tomography) scanning. Since CT scanning has entered the field of manufacturing and coordinate metrology, evaluation of uncertainty of measurement with assessment...

  1. Basic principles of cone beam computed tomography.

    Science.gov (United States)

    Abramovitch, Kenneth; Rice, Dwight D

    2014-07-01

    At the end of the millennium, cone-beam computed tomography (CBCT) heralded a new dental technology for the next century. Owing to the dramatic and positive impact of CBCT on implant dentistry and orthognathic/orthodontic patient care, additional applications for this technology soon evolved. New software programs were developed to improve the applicability of, and access to, CBCT for dental patients. Improved, rapid, and cost-effective computer technology, combined with the ability of software engineers to develop multiple dental imaging applications for CBCT with broad diagnostic capability, have played a large part in the rapid incorporation of CBCT technology into dentistry. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Computed tomography-controlled stereotactic surgery

    International Nuclear Information System (INIS)

    Matsumoto, Keizo; Shichijo, Fumio; Gyoten, Tetsuya; Tomida, Keisuke; Miyake, Hajime

    1986-01-01

    A single use of coordinate system of computed tomography (CT) scanner is utilized for CT-controlled stereotactic surgery. Depth, direction and readjustment of target trajectory were defined by known values of cursor number in CT images and numbers of the sliding table indicator. We loaded calculation formulas into hand held computer to obtain immediate answers. Stereotactic apparatus consisted two main parts: the patient's head fixation and probe holder. Surgery was performed in cases of hypertensive intracerebral hemorrhage for evacuation of the hematomas successfully. Target accuracy was satisfactory. With further advance of this surgery, automatic stereotactic control with a special robot machine seeing possible. (author)

  3. Hybrid Single Photon Emission Computed Tomography/Computed Tomography Sulphur Colloid Scintigraphy in Focal Nodular Hyperplasia

    International Nuclear Information System (INIS)

    Bhoil, Amit; Gayana, Shankramurthy; Sood, Ashwani; Bhattacharya, Anish; Mittal, Bhagwant Rai

    2013-01-01

    It is important to differentiate focal nodular hyperplasia (FNH), a benign condition of liver most commonly affecting women, from other neoplasm such as hepatic adenoma and metastasis. The functional reticuloendothelial features of FNH can be demonstrated by scintigraphy. We present a case of breast cancer in whom fluorodeoxyglucose positron emission tomography/computerized tomography (CT) showed a homogenous hyperdense lesion in liver, which on Tc99m sulfur colloid single-photon emission computed tomography/CT was found to have increased focal tracer uptake suggestive of FNH

  4. Applications of X-ray Computed Tomography and Emission Computed Tomography

    International Nuclear Information System (INIS)

    Seletchi, Emilia Dana; Sutac, Victor

    2005-01-01

    Computed Tomography is a non-destructive imaging method that allows visualization of internal features within non-transparent objects such as sedimentary rocks. Filtering techniques have been applied to circumvent the artifacts and achieve high-quality images for quantitative analysis. High-resolution X-ray computed tomography (HRXCT) can be used to identify the position of the growth axis in speleothems by detecting subtle changes in calcite density between growth bands. HRXCT imagery reveals the three-dimensional variability of coral banding providing information on coral growth and climate over the past several centuries. The Nuclear Medicine imaging technique uses a radioactive tracer, several radiation detectors, and sophisticated computer technologies to understand the biochemical basis of normal and abnormal functions within the brain. The goal of Emission Computed Tomography (ECT) is to accurately determine the three-dimensional radioactivity distribution resulting from the radiopharmaceutical uptake inside the patient instead of the attenuation coefficient distribution from different tissues as obtained from X-ray Computer Tomography. ECT is a very useful tool for investigating the cognitive functions. Because of the low radiation doses associated with Positron Emission Tomography (PET), this technique has been applied in clinical research, allowing the direct study of human neurological diseases. (authors)

  5. Validation of a Monte Carlo model used for simulating tube current modulation in computed tomography over a wide range of phantom conditions/challenges

    Energy Technology Data Exchange (ETDEWEB)

    Bostani, Maryam, E-mail: mbostani@mednet.ucla.edu; McMillan, Kyle; Cagnon, Chris H.; McNitt-Gray, Michael F. [Departments of Biomedical Physics and Radiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90024 (United States); DeMarco, John J. [Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, California 90095 (United States)

    2014-11-01

    Purpose: Monte Carlo (MC) simulation methods have been widely used in patient dosimetry in computed tomography (CT), including estimating patient organ doses. However, most simulation methods have undergone a limited set of validations, often using homogeneous phantoms with simple geometries. As clinical scanning has become more complex and the use of tube current modulation (TCM) has become pervasive in the clinic, MC simulations should include these techniques in their methodologies and therefore should also be validated using a variety of phantoms with different shapes and material compositions to result in a variety of differently modulated tube current profiles. The purpose of this work is to perform the measurements and simulations to validate a Monte Carlo model under a variety of test conditions where fixed tube current (FTC) and TCM were used. Methods: A previously developed MC model for estimating dose from CT scans that models TCM, built using the platform of MCNPX, was used for CT dose quantification. In order to validate the suitability of this model to accurately simulate patient dose from FTC and TCM CT scan, measurements and simulations were compared over a wide range of conditions. Phantoms used for testing range from simple geometries with homogeneous composition (16 and 32 cm computed tomography dose index phantoms) to more complex phantoms including a rectangular homogeneous water equivalent phantom, an elliptical shaped phantom with three sections (where each section was a homogeneous, but different material), and a heterogeneous, complex geometry anthropomorphic phantom. Each phantom requires varying levels of x-, y- and z-modulation. Each phantom was scanned on a multidetector row CT (Sensation 64) scanner under the conditions of both FTC and TCM. Dose measurements were made at various surface and depth positions within each phantom. Simulations using each phantom were performed for FTC, detailed x–y–z TCM, and z-axis-only TCM to obtain

  6. Positron emission tomography/computed tomography imaging and rheumatoid arthritis.

    Science.gov (United States)

    Wang, Shi-Cun; Xie, Qiang; Lv, Wei-Fu

    2014-03-01

    Rheumatoid arthritis (RA) is a phenotypically heterogeneous, chronic, destructive inflammatory disease of the synovial joints. A number of imaging tools are currently available for evaluation of inflammatory conditions. By targeting the upgraded glucose uptake of infiltrating granulocytes and tissue macrophages, positron emission tomography/computed tomography with fluorine-18 fluorodeoxyglucose ((18) F-FDG PET/CT) is available to delineate inflammation with high sensitivity. Recently, several studies have indicated that FDG uptake in affected joints reflects the disease activity of RA. In addition, usage of FDG PET for the sensitive detection and monitoring of the response to treatment has been reported. Combined FDG PET/CT enables the detailed assessment of disease in large joints throughout the whole body. These unique capabilities of FDG PET/CT imaging are also able to detect RA-complicated diseases. Therefore, PET/CT has become an excellent ancillary tool to assess disease activity and prognosis in RA. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  7. 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. Copyright © 2010. Published by Elsevier Inc.

  8. Hereditary haemorrhagic telangiectasia: study of hepatic vascular alterations with multi-detector row helical CT and reconstruction programs; Telangiectasia emorragica ereditaria: TC multidetettore multifasica e programmi di ricostruzione nello studio delle alterazioni vascolari epatiche

    Energy Technology Data Exchange (ETDEWEB)

    Memeo, Maurizio; Stabile Ianora, Amato Antonio; Scaldapane, Arnaldo; Rotondo, Antonio; Angelelli, Giuseppe [Policlinico Universitario, Bari (Italy). DiMIMP Sezione di Diagnostica per Immagini; Suppressa, Patrizia; Cirulli, Anna; Sabba' , Carlo [Policlinico Universitario, Bari (Italy). Centro Interdipartimentale per lo studio dell' HHT

    2005-02-01

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

  9. Mathematics in computed tomography and related techniques

    International Nuclear Information System (INIS)

    Sawicka, B.

    1992-01-01

    The mathematical basis of computed tomography (CT) was formulated in 1917 by Radon. His theorem states that the 2-D function f(x,y) can be determined at all points from a complete set of its line integrals. Modern methods of image reconstruction include three approaches: algebraic reconstruction techniques with simultaneous iterative reconstruction or simultaneous algebraic reconstruction; convolution back projection; and the Fourier transform method. There is no one best approach. Because the experimental data do not strictly satisfy theoretical models, a number of effects have to be taken into account; in particular, the problems of beam geometry, finite beam dimensions and distribution, beam scattering, and the radiation source spectrum. Tomography with truncated data is of interest, employing mathematical approximations to compensate for the unmeasured projection data. Mathematical techniques in image processing and data analysis are also extensively used. 13 refs

  10. 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)

  11. Positron computed tomography: current state, clinical results and future trends

    Energy Technology Data Exchange (ETDEWEB)

    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)

  12. Positron computed tomography: current state, clinical results and future trends

    International Nuclear Information System (INIS)

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

    1980-01-01

    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

  13. RELIABILITY OF POSITRON EMISSION TOMOGRAPHY-COMPUTED TOMOGRAPHY IN EVALUATION OF TESTICULAR CARCINOMA PATIENTS.

    Science.gov (United States)

    Nikoletić, Katarina; Mihailović, Jasna; Matovina, Emil; Žeravica, Radmila; Srbovan, Dolores

    2015-01-01

    The study was aimed at assessing the reliability of 18F-fluorodeoxyglucose positron emission tomography-computed tomography scan in evaluation of testicular carcinoma patients. The study sample consisted of 26 scans performed in 23 patients with testicular carcinoma. According to the pathohistological finding, 14 patients had seminomas, 7 had nonseminomas and 2 patients had a mixed histological type. In 17 patients, the initial treatment was orchiectomy+chemotherapy, 2 patients had orchiectomy+chemotherapy+retroperitoneal lymph node dissection, 3 patients had orchiectomy only and one patient was treated with chemotherapy only. Abnormal computed tomography was the main cause for the oncologist to refer the patient to positron emission tomography-computed tomography scan (in 19 scans), magnetic resonance imaging abnormalities in 1 scan, high level oftumor markers in 3 and 3 scans were perforned for follow-up. Positron emission tomography-computed tomography imaging results were compared with histological results, other imaging modalities or the clinical follow-up of the patients. Positron emission tomography-computed tomography scans were positive in 6 and negative in 20 patients. In two patients, positron emission tomography-computed tomography was false positive. There were 20 negative positron emission omography-computed tomography scans perforned in 18 patients, one patient was lost for data analysis. Clinically stable disease was confirmed in 18 follow-up scans performed in 16 patients. The values of sensitivty, specificity, accuracy, and positive- and negative predictive value were 60%, 95%, 75%, 88% and 90.5%, respectively. A hgh negative predictive value obtained in our study (90.5%) suggests that there is a small possibility for a patient to have future relapse after normal positron emission tomography-computed tomography study. However, since the sensitivity and positive predictive value of the study ire rather low, there are limitations of positive

  14. Total variation-based neutron computed tomography

    Science.gov (United States)

    Barnard, Richard C.; Bilheux, Hassina; Toops, Todd; Nafziger, Eric; Finney, Charles; Splitter, Derek; Archibald, Rick

    2018-05-01

    We perform the neutron computed tomography reconstruction problem via an inverse problem formulation with a total variation penalty. In the case of highly under-resolved angular measurements, the total variation penalty suppresses high-frequency artifacts which appear in filtered back projections. In order to efficiently compute solutions for this problem, we implement a variation of the split Bregman algorithm; due to the error-forgetting nature of the algorithm, the computational cost of updating can be significantly reduced via very inexact approximate linear solvers. We present the effectiveness of the algorithm in the significantly low-angular sampling case using synthetic test problems as well as data obtained from a high flux neutron source. The algorithm removes artifacts and can even roughly capture small features when an extremely low number of angles are used.

  15. Cross-sectional anatomy for computed tomography

    International Nuclear Information System (INIS)

    Farkas, M.L.

    1988-01-01

    This self-study guide recognizes that evaluation and interpretation of CT-images demands a firm understanding of both cross-sectional anatomy and the principles of computed tomography. The objectives of this book are: to discuss the basic principles of CT, to stress the importance of cross-sectional anatomy to CT through study of selected cardinal transverse sections of head, neck, and trunk, to explain orientation and interpretation of CT-images with the aid of corresponding cross-sectional preparations

  16. Computed tomography scans of metastatic hepatic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Takemoto, Kazumasa; Fukuda, Haruyuki; Nemoto, Yutaka [Osaka City Univ. (Japan). Faculty of Medicine

    1984-01-01

    Computed tomography scans of 114 metastatic hepatic tumors were reviewed. Central low density was found in 82 cases (71.9%) and seems to be characteristic to metastatic hepatic tumors. Dynamic CT was performed on 34 cases, and 21 (61.8%) of these had ring enhancement at the arterial phase. Most of metastatic hepatic tumors could be differentiated from hepatocellular carcinoma. However, metastatic hepatic tumors from renal cell carcinoma, renal rhabdomyosarcoma, malignant melanoma and leiomyosarcoma could not be differentiated from hepatocellular carcinoma, even with use of dynamic study.

  17. Computed tomography appearances of sclerosing encapsulating peritonitis

    International Nuclear Information System (INIS)

    George, C.; Al-Zwae, K.; Nair, S.; Cast, J.E.I.

    2007-01-01

    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

  18. An industrial application of computer assisted tomography

    International Nuclear Information System (INIS)

    Tonner, P.D.; Tosello, G.

    1984-10-01

    Computer assisted tomography (CAT) scanning is a nondestructive testing technique used to obtain quantitatively accurate mappings of the distribution of linear attenuation coefficients inside an object. To demonstrate the potential of the technique for accurately locating defects in three dimensions a sectioned 5 cm gate valve, with a shrink cavity made visible by the sectioning, was tomographically imaged using a Co-60 source. The tomographic images revealed a larger cavity below the sectioned surface. The position of this cavity was located with an in-plane and axial precision of approximately +- 1 mm. The volume of the cavity was estimated to be approximately 40 mm 3

  19. Application of protons to computer tomography

    International Nuclear Information System (INIS)

    Hanson, K.M.; Bradbury, J.N.; Cannon, T.M.; Hutson, R.L.; Laubacher, D.B.; Macek, R.; Paciotti, M.A.; Taylor, C.A.

    1977-01-01

    It was demonstrated that the application of protons to computed tomography can result in a significant dose advantage relative to x rays. Thus, at the same dose as is delivered by contemporary commercial x-ray scanners, a proton scanner could produce reconstructions with a factor of 2 or more improvement in density resolution. Whether such an improvement can result in significantly better diagnoses of human disease is an open question which can only be answered by the implementation of a proton scanner in a clinical situation

  20. Contrast media on abdominal computed tomography

    International Nuclear Information System (INIS)

    Skalpe, I.O.; Oestensen, H.M.

    1984-01-01

    Abdominal computed tomography was performed in 55 patients before and after intravenous injection of 60 ml of a non-ionic (iohexol) or an ionic (metrizoate) contrast medium. The adverse effects were recorded and a series of measurements of attenuation values before and after the contrast medium injection was performed in the aorta and in hepatic and renal parenchyma. Only minor adverse effects were seen with both contrast media, but iohexol was clearly better tolerated than metrizoate. No difference in the enhancement properties was found between the two contrast media. (orig.)

  1. 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.

  2. Computed tomography of the spine: Diagnostic exercises

    International Nuclear Information System (INIS)

    Kricun, R.; Kricun, M.E.

    1987-01-01

    The authors' aim is to provide diagnostic challenges and information to improve the readers' ability to interpret computed tomography (CT) scans of the spine. The entire vertebral column and adjacent soft-tissue structures are covered. The authors discuss normal findings, and congenital, traumatic, inflammatory, neoplastic, degenerative, idiopathic, and postoperative findings. Sixty-six case examples are presented, followed by description of the findings. Additional examples are given, and drawings and photographs of specimens are used to illustrate and clarify the pathologic conditions. Other modalities, including their advantages and disadvantages, are illustrated and discussed where appropriate. The relative merits of these modalities are presented

  3. Computed tomography features of small bowel volvulus

    International Nuclear Information System (INIS)

    Loh, Y.H.; Dunn, G.D.

    2000-01-01

    Small bowel volvulus is a cause of acute abdomen and commonly occurs in neonates and young infants. Although it is rare in adults in the Western world,' it is a relatively common surgical emergency in the Middle East, India and Central Africa. It is associated with a mortality rate of 10-67% and, hence, it is important to make an early diagnosis to expedite surgical intervention. Computed tomography has become an important imaging modality in diagnosis and a number of signs have been recognized in a handful of documented case reports. We describe a case of small bowel volvulus that illustrates these important CT signs. Copyright (1999) Blackwell Science Pty Ltd

  4. Computed tomography in neuronal ceroid lipofuscinosis

    International Nuclear Information System (INIS)

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

    1981-01-01

    The computed tomography (CT) findings in a verified case of neutronal 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. (orig.) [de

  5. Unusual causes of obstructive jaundice. Computed tomography

    International Nuclear Information System (INIS)

    Rodriguez, E.; Pombo, F.; Cao, I.; Fernandez, R.; Riba da, M.

    1998-01-01

    The purpose of this study is to present selected computed tomography (CT) images showing unusual causes of obstructive jaundice. We reviewed retrospectively the Ct findings of obstructive jaundice in 227 patients. The most common causes of biliary obstruction were adenocarcinoma of the pancreatic head (n=77) and cholangiocarcinoma (n=65). In 13 cases (5.7%), the etiology of obstructive jaundice was unusual or exceptional: tuberculous adenitis (n=3), obstruction of afferent loop (n=2)signet ring cell adenocarcinoma (n=3); in duodenum, gallbladder and papilla of Water), Mirizzi syndrome (n=1), adenocarcinoma of the hepatic flexure (n=1), choledochal cyst (n=1) and pancreatic lymphoma (n=1). (Author) 13 refs

  6. Electrocardiographic gating in positron emission computed tomography

    International Nuclear Information System (INIS)

    Hoffman, E.J.; Phelps, M.E.; Wisenberg, G.; Schelbert, H.R.; Kuhl, D.E.

    1979-01-01

    Electrocardiographic (ECG) synchronized multiple gated data acquisition was employed with positron emission computed tomography (ECT) to obtain images of myocardial blood pool and myocardium. The feasibility and requirements of multiple gated data acquisition in positron ECT were investigated for 13NH3, ( 18 F)-2-fluoro-2-D-deoxyglucose, and ( 11 C)-carboxyhemoglobin. Examples are shown in which image detail is enhanced and image interpretation is facilitated when ECG gating is employed in the data collection. Analysis of count rate data from a series of volunteers indicates that multiple, statistically adequate images can be obtained under a multiple gated data collection format without an increase in administered dose

  7. Ground-glass opacity: High-resolution computed tomography and 64-multi-slice computed tomography findings comparison

    International Nuclear Information System (INIS)

    Sergiacomi, Gianluigi; Ciccio, Carmelo; Boi, Luca; Velari, Luca; Crusco, Sonia; Orlacchio, Antonio; Simonetti, Giovanni

    2010-01-01

    Objective: Comparative evaluation of ground-glass opacity using conventional high-resolution computed tomography technique and volumetric computed tomography by 64-row multi-slice scanner, verifying advantage of volumetric acquisition and post-processing technique allowed by 64-row CT scanner. Methods: Thirty-four patients, in which was assessed ground-glass opacity pattern by previous high-resolution computed tomography during a clinical-radiological follow-up for their lung disease, were studied by means of 64-row multi-slice computed tomography. Comparative evaluation of image quality was done by both CT modalities. Results: It was reported good inter-observer agreement (k value 0.78-0.90) in detection of ground-glass opacity with high-resolution computed tomography technique and volumetric Computed Tomography acquisition with moderate increasing of intra-observer agreement (k value 0.46) using volumetric computed tomography than high-resolution computed tomography. Conclusions: In our experience, volumetric computed tomography with 64-row scanner shows good accuracy in detection of ground-glass opacity, providing a better spatial and temporal resolution and advanced post-processing technique than high-resolution computed tomography.

  8. Computed tomography in the diagnosis of pericardial heart disease

    International Nuclear Information System (INIS)

    Isner, J.M.; Carter, B.L.; Bankoff, M.S.; Konstam, M.A.; Salem, D.N.

    1982-01-01

    To evaluate the use of computed tomography (CT) in the diagnosis of pericardial heart disease, 53 patients were prospectively studied by computed tomography of the chest and cardiac ultrasound. A diagnostic-quality CT study was done for all patients; a technically satisfactory ultrasound examination was not possible in six patients. Of 47 patients in whom both chest scans and satisfactory ultrasound studies were obtained, computed tomography showed pericardial thickening not shown by ultrasound in five patients. Estimated size of pericardial effusion was the same for both computed tomography and ultrasound. Computed tomography provided quantifiable evaluation of the composition of pericardial fluid in seven patients with either hemopericardium or purulent pericarditis. Neoplastic pericardial heart disease was detected by CT scan in four of the 53 patients. Computed tomography of the chest provides a sensitive evaluation of the pericardium and quality of pericardial effusion, and is a valuable adjunct in patients in whom cardiac ultrasound is technically unsatisfactory

  9. Computed tomography by reconstruction. Brain CT scanning. I. Basic physics, equipment, normal aspects, artefacts

    International Nuclear Information System (INIS)

    Chiras, J.; Palmieri, P.; Saudinos, J.; Salamon, G.

    1980-01-01

    The authors describe the physical basis, apparatus, normal images, and artefacts of computed tomography by reconstruction. Radio-anatomical sections enable clear comprehension of the computed tomography images. Other methods using computer reconstruction are outlined: tomography by Compton effect, tomography by positrons, tomography by gamma emission, tomography by protons, tomography by nuclear magnetic resonance [fr

  10. Speeding up image reconstruction in computed tomography

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    Computed tomography (CT) is a technique for imaging cross-sections of an object using X-ray measurements taken from different angles. In last decades a significant progress has happened there: today advanced algorithms allow fast image reconstruction and obtaining high-quality images even with missing or dirty data, modern detectors provide high resolution without increasing radiation dose, and high-performance multi-core computing devices are there to help us solving such tasks even faster. I will start with CT basics, then briefly present existing classes of reconstruction algorithms and their differences. After that I will proceed to employing distinctive architectural features of modern multi-core devices (CPUs and GPUs) and popular program interfaces (OpenMP, MPI, CUDA, OpenCL) for developing effective parallel realizations of image reconstruction algorithms. Decreasing full reconstruction time from long hours up to minutes or even seconds has a revolutionary impact in diagnostic medicine and industria...

  11. Comparison of computed tomography dose reporting software

    International Nuclear Information System (INIS)

    Abdullah, A.; Sun, Z.; Pongnapang, N.; Ng, K. H.

    2008-01-01

    Computed tomography (CT) dose reporting software facilitates the estimation of doses to patients undergoing CT examinations. In this study, comparison of three software packages, i.e. CT-Expo (version 1.5, Medizinische Hochschule, Hannover (Germany)), ImPACT CT Patients Dosimetry Calculator (version 0.99x, Imaging Performance Assessment on Computed Tomography, www.impactscan.org) and WinDose (version 2.1a, Wellhofer Dosimetry, Schwarzenbruck (Germany)), has been made in terms of their calculation algorithm and the results of calculated doses. Estimations were performed for head, chest, abdominal and pelvic examinations based on the protocols recommended by European guidelines using single-slice CT (SSCT) (Siemens Somatom Plus 4, Erlangen (Germany)) and multi-slice CT (MSCT) (Siemens Sensation 16, Erlangen (Germany)) for software-based female and male phantoms. The results showed that there are some differences in final dose reporting provided by these software packages. There are deviations of effective doses produced by these software packages. Percentages of coefficient of variance range from 3.3 to 23.4 % in SSCT and from 10.6 to 43.8 % in MSCT. It is important that researchers state the name of the software that is used to estimate the various CT dose quantities. Users must also understand the equivalent terminologies between the information obtained from the CT console and the software packages in order to use the software correctly. (authors)

  12. Computed tomography of juvenile nasopharyngeal angiofibroma

    Energy Technology Data Exchange (ETDEWEB)

    Park, Cheong Hee; Yoo, Shi Joon; Lee, Yul; Chang, Kee Hyun; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1985-02-15

    It is well known that computed tomography (CT) is useful in detecting accurately the location, extent, erosion and relationship of angiofibroma to surrounding structures such as pterygopalation fossa. It is well known that computed tomography (CT) is useful in detecting accurately the location, sphenoid sinus, and etc. CT of 20 patients with juvenile angiofibroma, which were examined for 5 yeas from February, 1979 to May, 1984 at Department of Radiology, Seoul National University Hospital, were retrospectively analyzed. The results were as follows: 1. All 20 patients of juvenile angiofibroma had tumors in nasopharynx and posterior nasal cavity showing homogeneously dense-enhancing soft tissue mass on CT. There was extension of the tumor from nasopharynx and posterior nasal cavity into paranasal sinus (60%, 12/20), pterygopalatine fossa (55%, 11/20), infratemporal fossa (30%, 6/20), posterior orbit (10%, 2/20) and cranial cavity (15%, 3/20). 2. Angiogrpahy usually adds little diagnostic information, but is still needed to identify the precise source of blood supply to the tumor, and to perform the pre-operative embolization. The use of CT has deferred angiography until just before surgery, permitting embolization at optimal time. 3. CT is almost always necessary to reveal accurately the full extent of the tumor, especially intracranial space in the axial and coronal planes with contrast enhancement. CT is useful both in diagnosis as a guide to angiography and in planning the adequate therapy of juvenile angiofibroma.

  13. Evaluation of valvular heart diseases with computed tomography

    International Nuclear Information System (INIS)

    Tomoda, Haruo; Hoshiai, Mitsumoto; Matsuyama, Seiya

    1982-01-01

    Forty-two patients with valvular heart diseases were studied with a third-generation computed tomographic system. The cardiac chambers (the atria and ventricles) were evaluated semiquantitatively, and valvular calcification was easily detected with computed tomography. Computed tomography was most valuable in revealing left atrial thrombi which were not identified by other diagnostic procedures in some cases. (author)

  14. A Clinical Evaluation Of Cone Beam Computed Tomography

    Science.gov (United States)

    2016-06-01

    A CLINICAL EVALUATION OF CONE BEAM COMPUTED TOMOGRAPHY by Bryan James Behm, D.D.S. Lieutenant, Dental Corps United States Navy A thesis... COMPUTED TOMOGRAPHY " is appropriately acknowledged and, beyond brief excerpts, is with the permission of the copyright owner. ~mes Behm Endodontic...printed without the expressed written permission of the author. IV ABSTRACT A CLINICAL EVALUATION OF CONE BEAM COMPUTED TOMOGRAPHY BRYAN JAMES

  15. Computed tomography of post-traumatic orbito-palpebral emphysema

    International Nuclear Information System (INIS)

    Nose, Harumi; Kohno, Keiko

    1981-01-01

    Two cases of orbito-palpebral emphysema are described. Both having a history of recent facial trauma, emphysema occurred after blowing the nose. They were studied by computed tomography and plain x-ray film, including tomograms of the orbit. The emphysema was revealed by computed tomography and x-ray film, but more clearly by the former technique. The fracture lines of the orbit were revealed in only one case by x-ray film, but in both cases by computed tomography. The authors stress that computed tomography is the best technique for the study of orbital emphysema. (author)

  16. Computed Tomography Technology: Development and Applications for Defence

    International Nuclear Information System (INIS)

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

    2008-01-01

    Computed Tomography(CT) has revolutionized the field of Non-Destructive Testing and Evaluation (NDT and 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.

  17. Investigation of the relative effects of vascular branching structure and gravity on pulmonary arterial blood flow heterogeneity via an image-based computational model.

    Science.gov (United States)

    Burrowes, Kelly S; Hunter, Peter J; Tawhai, Merryn H

    2005-11-01

    A computational model of blood flow through the human pulmonary arterial tree has been developed to investigate the relative influence of branching structure and gravity on blood flow distribution in the human lung. Geometric models of the largest arterial vessels and lobar boundaries were first derived using multidetector row x-ray computed tomography (MDCT) scans. Further accompanying arterial vessels were generated from the MDCT vessel endpoints into the lobar volumes using a volume-filling branching algorithm. Equations governing the conservation of mass and momentum were solved within the geometric model to calculate pressure, velocity, and vessel radius. Blood flow results in the anatomically based model, with and without gravity, and in a symmetric geometric model were compared to investigate their relative contributions to blood flow heterogeneity. Results showed a persistent blood flow gradient and flow heterogeneity in the absence of gravitational forces in the anatomically based model. Comparison with flow results in the symmetric model revealed that the asymmetric vascular branching structure was largely responsible for producing this heterogeneity. Analysis of average results in varying slice thicknesses illustrated a clear flow gradient because of gravity in "lower resolution" data (thicker slices), but on examination of higher resolution data, a trend was less obvious. Results suggest that although gravity does influence flow distribution, the influence of the tree branching structure is also a dominant factor. These results are consistent with high-resolution experimental studies that have demonstrated gravity to be only a minor determinant of blood flow distribution.

  18. Computed tomography findings in convergent strabismus fixus

    International Nuclear Information System (INIS)

    Ohta, Michitaka; Iwashige, Hiroyasu; Hayashi, Takao; Maruo, Toshio

    1995-01-01

    X-ray computed tomography (CT) of the eyeball and orbit revealed the cause of eye movement disorder in convergent strabismus fixus. The findings suggest that the disease can be diagnosed and treated at an early stage. Twelve cases of progressive esotropia with high myopia and 20 cases with normal visual acuity served as subjects in this study. The CT slice was parallel to the German horizontal plane, and the lens and medial and lateral rectus muscles were scanned. The average axial length of the affected eyes was significantly longer than in normal eyes. In progressive esotropia, the characteristic CT findings are an elongated eyeball, mechanical contact between the eyeball and lateral wall of the orbit, and a downward displacement of the lateral rectus muscle. Thus, it is reasonable to conclude that eye movement disorder in convergent strabismus fixus results from weakness of the lateral rectus muscle which has been displaced downward due to compression of the eyeball against the orbital wall. (author)

  19. Technological Evolution on Computed Tomography and Radioprotection

    Energy Technology Data Exchange (ETDEWEB)

    Leite, Bruno Barros; Ribeiro, Nuno Carrilho [Servico de Radiologia, Hospital de Curry Cabral, Rua da Beneficencia, 8, 1069-166 Lisboa (Portugal)

    2006-05-15

    Computed Tomography (CT) has been available since the 70s and has experienced a dramatic technical evolution. Multi-detector technology is our current standard, offering capabilities unthinkable only a decade ago. Yet, we must nor forget the ionizing nature of CT's scanning energy (X-rays). It represents the most important cause of medical-associated radiation exposure to the general public, with a trend to increase. It is compulsory to intervene with the objective of dose reduction, following ALARA policies. Currently there are some technical advances that allow dose reduction, without sacrificing diagnostic image capabilities. However, human intervention is also essential. We must keep investment on education so that CT exams are don when they are really useful in clinical decision. Alternative techniques should also be considered. Image quality must not be searched disregarding the biological effects of radiation. Generally, it is possible to obtain clinically acceptable images with lower dose protocols. (author)

  20. Computed tomography of the traumatized abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Young Woon; Baik, Seung Kug; Lee, Jong Yul; Choi, Han Yong; Kim, Bong Ki [Wallace Memotial Baptist Hospital, Pusan (Korea, Republic of)

    1989-02-15

    Forty-seven patients with abdominal and retroperitoneal injuries were examined by computed tomography(CT). We analyzed the results of 47 patients who were confirmed of abdominal injuries by operation, clinical follow up, and repeated radiologic examinations. 1. the type of trauma was blunt in 38 patients (81%) and penerating in 9 patients (19%) 2. There were 14 splenic, 11 renal, 9 hepatic, 6 retroperitoneal, 4 pancreatic, and 3 alimentary tract injuries. 3. The patients who had been treated by conservative management were 23.4% (surgical treatment,76.6%). 4. The six ratio was 4.9 : 1.0 (male ; female). 5. CT has major advantage over plain radiography, radionuclide imaging, and angiography in assessment of trauma-induced injuries.

  1. Computed tomography of the traumatized abdomen

    International Nuclear Information System (INIS)

    Yoon, Young Woon; Baik, Seung Kug; Lee, Jong Yul; Choi, Han Yong; Kim, Bong Ki

    1989-01-01

    Forty-seven patients with abdominal and retroperitoneal injuries were examined by computed tomography(CT). We analyzed the results of 47 patients who were confirmed of abdominal injuries by operation, clinical follow up, and repeated radiologic examinations. 1. the type of trauma was blunt in 38 patients (81%) and penerating in 9 patients (19%) 2. There were 14 splenic, 11 renal, 9 hepatic, 6 retroperitoneal, 4 pancreatic, and 3 alimentary tract injuries. 3. The patients who had been treated by conservative management were 23.4% (surgical treatment,76.6%). 4. The six ratio was 4.9 : 1.0 (male ; female). 5. CT has major advantage over plain radiography, radionuclide imaging, and angiography in assessment of trauma-induced injuries

  2. Multidetector Computed Tomography and Neuroendocrine Pancreaticoduodenal Tumors

    International Nuclear Information System (INIS)

    Rappeport, E.D.; Palnaes Hansen, C.; Kjaer, A.; Knigge, U.

    2006-01-01

    Purpose: To investigate the accuracy of dedicated pancreatic multidetector computed tomography (MDCT) in the diagnosis of neuroendocrine pancreaticoduodenal tumors (NPTs). Material and Methods: MDCT and other imaging studies in patients with suspected NPTs were identified. Thirty dedicated MDCT studies were done in 23 patients. Fourteen patients (16 operations) subsequently had surgery. Imaging reports were reviewed and findings compared with surgical findings and findings in other imaging studies. Results: Patients with surgery : 19 NPTs (16 extrapancreatic gastrinomas and 3 pancreatic NPTs) were identified at surgery. MDCT identified 16 and somatostatin receptor scintigraphy (SRS) 11 out of 19 tumors. Endoscopic ultrasound detected 11 out of 14 NPTs. Patients without surgery : In 4 out of 9 patients, no NPTs were identified at MDCT. Conclusion: Dedicated MDCT of the pancreas can identify many NPTs, including small duodenal and periduodenal tumors, and the detection rate is better than reported in the older literature on CT

  3. Quality control in quantitative computed tomography

    International Nuclear Information System (INIS)

    Jessen, K.A.; Joergensen, J.

    1989-01-01

    Computed tomography (CT) has for several years been an indispensable tool in diagnostic radiology, but it is only recently that extraction of quantitative information from CT images has been of practical clinical value. Only careful control of the scan parameters, and especially the scan geometry, allows useful information to be obtained; and it can be demonstrated by simple phantom measurements how sensitive a CT system can be to variations in size, shape and position of the phantom in the gantry aperture. Significant differences exist between systems that are not manifested in normal control of image quality and general performance tests. Therefore an actual system has to be analysed for its suitability for quantitative use of the images before critical clinical applications are justified. (author)

  4. Technological Evolution on Computed Tomography and Radioprotection

    International Nuclear Information System (INIS)

    Leite, Bruno Barros; Ribeiro, Nuno Carrilho

    2006-01-01

    Computed Tomography (CT) has been available since the 70s and has experienced a dramatic technical evolution. Multi-detector technology is our current standard, offering capabilities unthinkable only a decade ago. Yet, we must nor forget the ionizing nature of CT's scanning energy (X-rays). It represents the most important cause of medical-associated radiation exposure to the general public, with a trend to increase. It is compulsory to intervene with the objective of dose reduction, following ALARA policies. Currently there are some technical advances that allow dose reduction, without sacrificing diagnostic image capabilities. However, human intervention is also essential. We must keep investment on education so that CT exams are don when they are really useful in clinical decision. Alternative techniques should also be considered. Image quality must not be searched disregarding the biological effects of radiation. Generally, it is possible to obtain clinically acceptable images with lower dose protocols. (author)

  5. The temporomandibular joint in computed tomography

    International Nuclear Information System (INIS)

    Pomaroli, A.; Lener, M.

    1988-01-01

    The first part describes details of the temporomandibular joint (TMJ) which are of interest for the examination by computed tomography. In the second part three new planes of reference for scanning of the ventral, middle or dorsal part of the joint are presented. CT examinations were made of 14 TMJ of corpses to identify the medial or ventral parts of the articular disc, medial wall of the articular capsule and medial or triangular recessus to achieve this were scanned the corpses with opened and closed mouth, as well as with closed sets of teeth using a sort of hypomochlion in the molar region to distract the TMJ. More over we applicated different contrast mediums like air and niob. (orig.) [de

  6. Neutron stimulated emission computed tomography: Background corrections

    International Nuclear Information System (INIS)

    Floyd, Carey E.; Sharma, Amy C.; Bender, Janelle E.; Kapadia, Anuj J.; Xia, Jessie Q.; Harrawood, Brian P.; Tourassi, Georgia D.; Lo, Joseph Y.; Kiser, Matthew R.; Crowell, Alexander S.; Pedroni, Ronald S.; Macri, Robert A.; Tajima, Shigeyuki; Howell, Calvin R.

    2007-01-01

    Neutron stimulated emission computed tomography (NSECT) is an imaging technique that provides an in-vivo tomographic spectroscopic image of the distribution of elements in a body. To achieve this, a neutron beam illuminates the body. Nuclei in the body along the path of the beam are stimulated by inelastic scattering of the neutrons in the beam and emit characteristic gamma photons whose unique energy identifies the element. The emitted gammas are collected in a spectrometer and form a projection intensity for each spectral line at the projection orientation of the neutron beam. Rotating and translating either the body or the beam will allow a tomographic projection set to be acquired. Images are reconstructed to represent the spatial distribution of elements in the body. Critical to this process is the appropriate removal of background gamma events from the spectrum. Here we demonstrate the equivalence of two background correction techniques and discuss the appropriate application of each

  7. Computed tomography study of otitis media

    International Nuclear Information System (INIS)

    Bahia, Paulo Roberto Valle; Marchiori, Edson

    1997-01-01

    The findings of computed tomography (CT) of 89 patients clinically suspected of having otitis media were studied in this work. Such results were compared to clinical diagnosis, otoscopy, surgical findings and previous data. Among the results of our analysis, we studied seven patients with acute otitis media and 83 patients with chronic otitis media. The patients with acute otitis media have undergone CT examinations to evaluate possible spread to central nervous system. The diagnosis of cholesteatoma, its extension and complications were the main indication. for chronic otitis media study. The main findings of the cholesteatomatous otitis were the occupation of the epitympanun, the bony wall destruction and the ossicular chain erosion. The CT demonstrated a great sensibility to diagnose the cholesteatoma. (author)

  8. Diagnosis of cerebral disorders using computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kitamura, K [Tokyo Women' s Medical Coll. (Japan)

    1980-01-01

    Computed tomography (CT), which makes differential diagnosis of cerebral disorders possible, was applied in the diagnosis of hypertensive intracerebral hemorrhage, cerebral thrombosis, subarachnoid hemorrhage, and cerebrovascular Moyamoya disease. CT findings of hypertensive intracerebral hemorrhage showed the localization, volume, and direction of hematoma, and the classification of hematoma according to CT findings was highly correlated to the clinical symptoms of the patients. CT findings of cerebral thrombosis showed the extension of the lesion to be a low density area, but there were many cases in which they did not show a low density area immediately after an attack. CT findings of subarachnoid hemorrhage were very useful in the diagnosis of intracerebral hematoma, ventricular hematoma, and intracranial hematoma secondary to this disease. However, it was very difficult to diagnose cerebrovascular Moyamoya disease by means of CT.

  9. Diagnosis of cerebral disorders using computed tomography

    International Nuclear Information System (INIS)

    Kitamura, Koichi

    1980-01-01

    Computed tomography (CT), which makes differential diagnosis of cerebral disorders possible, was applied in the diagnosis of hypertensive intracerebral hemorrhage, cerebral thrombosis, subarachnoid hemorrhage, and cerebrovascular Moyamoya disease. CT findings of hypertensive intracerebral hemorrhage showed the localization, volume, and direction of hematoma, and the classification of hematoma according to CT findings was highly correlated to the clinical symptoms of the patients. CT findings of cerebral thrombosis showed the extension of the lesion to be a low density area, but there were many cases in which they did not show a low density area immediately after an attack. CT findings of subarachnoid hemorrhage were very useful in the diagnosis of intracerebral hematoma, ventricular hematoma, and intracranial hematoma secondary to this disease. However, it was very difficult to diagnose cerebrovascular Moyamoya disease by means of CT. (Nishio, M.)

  10. The dynamic micro computed tomography at SSRF

    Science.gov (United States)

    Chen, R.; Xu, L.; Du, G.; Deng, B.; Xie, H.; Xiao, T.

    2018-05-01

    Synchrotron radiation micro-computed tomography (SR-μCT) is a critical technique for quantitative characterizing the 3D internal structure of samples, recently the dynamic SR-μCT has been attracting vast attention since it can evaluate the three-dimensional structure evolution of a sample. A dynamic μCT method, which is based on monochromatic beam, was developed at the X-ray Imaging and Biomedical Application Beamline at Shanghai Synchrotron Radiation Facility, by combining the compressed sensing based CT reconstruction algorithm and hardware upgrade. The monochromatic beam based method can achieve quantitative information, and lower dose than the white beam base method in which the lower energy beam is absorbed by the sample rather than contribute to the final imaging signal. The developed method is successfully used to investigate the compression of the air sac during respiration in a bell cricket, providing new knowledge for further research on the insect respiratory system.

  11. Computed tomography of the pituitary gland

    International Nuclear Information System (INIS)

    Bonneville, J.F.; Cattin, F.; Dietemann, J.L.

    1986-01-01

    This book is written entirely to include the imaging of the pituitary gland by computed tomography (CT). The first three chapters illustrated technical aspects of scanning, anatomic depiction of the gland by CT, and the use of dynamic CT scanning for detecting and displaying abnormalities. The chapters discuss and illustrate various types of pathologic processes in and around the pituitary gland. One short but very helpful chapter demonstrates potential pitfalls due to the combination of anatomic variants and the geometry of CT sections. Some illustrations of disease processed are depicted by magnetic resonance imaging. All major types of pituitary diseases are illustrated. Lists of readily available English-language references are available. A small subject index is provided at the end of the book in which the illustrations are identified by use of a special numeric front

  12. Ward nurses' knowledge of computed tomography scanning.

    Science.gov (United States)

    Majeed, M A; Nayeemuddin, M; Christie, M

    Patients benefit from and are reassured by advance information on procedures that they are to undergo. Ward nurses should have adequate knowledge of radiological investigations to ensure proper patient preparation and good interdepartmental communication to avoid delays and cancellations. This study was conducted to assess the ward nurses' knowledge of the process of computed tomography (CT) scanning. One hundred and twenty qualified nurses were asked to complete a questionnaire regarding CT scanning. The findings revealed a suboptimal level of awareness about the process. This is probably due to lack of formal teaching for nurses on the wards in regards the different radiological procedures and patient preparation. There is a strong case for better educational talks on rapidly changing radiological techniques for ward staff to ensure high-quality patient care.

  13. Computed tomography study of Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Arai, H; Kobayashi, K; Ikeda, Y; Nagao, Y; Ogihara, R; Kosaka, K

    1983-01-01

    Computed tomography (CT) was used to study cerebral atrophy in 18 patients with clinically diagnosed Alzheimer's disease of presenile type and in 14 healthy age-matched subjects as controls. Using the computerized planimetric method, Subarachnoid Space Volume Index and Ventricle Volume Index were calculated as the measure of cortical atrophy and ventricular dilatation respectively. From the results the following conclusions were drawn: 1. The cerebral atrophy in Alzheimer patients could be attributable to the disease processes rather than to physiological aging of the brain. 2. The degree of atrophy increases in parallel with the progress of the clinical stage, and the cortical atrophy is already apparent at an early stage, whereas the ventricular dilatation becomes pronounced at later stages. 3. CT could be one of the most useful clinical tests available for the diagnosis of Alzheimer's disease.

  14. Practical techniques for pediatric computed tomography

    International Nuclear Information System (INIS)

    Fitz, C.R.; Harwood-Nash, D.C.; Kirks, D.R.; Kaufman, R.A.; Berger, P.E.; Kuhn, J.P.; Siegel, M.J.

    1983-01-01

    Dr. Donald Kirks has assembled this section on Practical Techniques for Pediatric Computed Tomography. The material is based on a presentation in the Special Interest session at the 25th Annual Meeting of the Society for Pediatric Radiology in New Orleans, Louisiana, USA in 1982. Meticulous attention to detail and technique is required to ensure an optimal CT examination. CT techniques specifically applicable to infants and children have not been disseminated in the radiology literature and in this respect it may rightly be observed that ''the child is not a small adult''. What follows is a ''cookbook'' prepared by seven participants and it is printed in Pediatric Radiology, in outline form, as a statement of individual preferences for pediatric CT techniques. This outline gives concise explanation of techniques and permits prompt dissemination of information. (orig.)

  15. Teleradiology for emergency cranial computed tomography

    International Nuclear Information System (INIS)

    Stranzinger, E.; Treumann, T.C.; Dreier, D.; Allgayer, B.

    2003-01-01

    Purpose: We report our experience with the teleradiologic service provided by a center hospital (CH) for emergency cranial computed tomography (CCT) in two regional hospitals (RH) during a 12-month period. The clinical and economic impact of teleradiology will be discussed as well as the acceptance by the clinicians of the regional hospitals. Material and Methods: In 2001, 213 CT-scans in 202 patients were performed and reported using teleradiology. Teleradiologic and final medical diagnosis were analysed by the medical reports. The transferral of the patients to a CH and their further treatment were checked. The referring physicians in the RH were questionnaired about the teleradiological support. Results: 18 (9%) patients had to be urgently transferred to a CH based on the CT findings in the teleradiological reports. 24 patients (11%) were transferred to a center hospital during further treatment. 80% of patients were treated in the RH. (orig.) [de

  16. Quality assurance of computed tomography (CT) scanners

    International Nuclear Information System (INIS)

    Sankaran, A.; Sanu, K.K. . Email : a_sankaran@vsnl.com

    2004-01-01

    This article reviews the present status of research work and development of various test objects, phantoms and detector/instrumentation systems for quality assurance (QA) of computed tomography (CT) scanners, carried out in advanced countries, with emphasis on similar work done in this research centre. CT scanner is a complex equipment and routine quality control procedures are essential to the maintenance of image quality with optimum patient dose. Image quality can be ensured only through correlation between prospective monitoring of system components and tests of overall performance with standard phantoms. CT examinations contribute a large share to the population dose in advanced countries. The unique dosimetry problems in CT necessitate special techniques. This article describes a comprehensive kit developed indigenously for the following QA and type approval tests as well as for research studies on image quality/dosimetry on CT scanners

  17. Minimising medically unwarranted computed tomography scans

    International Nuclear Information System (INIS)

    Brenner, D.J.

    2012-01-01

    As computed tomography (CT) is such a superb diagnostic tool and individual CT risks are small, whenever a CT scan is clinically warranted, the CT benefit/risk balance is by far in the patient’s favour. However, if a CT scan is not clinically warranted, this balance shifts dramatically. It is likely that at least 25% of CT scans fall into this latter category, in that they could either be replaced with alternative imaging modalities or could be avoided entirely. Use of clinical decision rules for CT usage represents a powerful approach for slowing down the increase in CT usage, because they have the potential to overcome some of the major factors that result in some CT scans being undertaken when they may not be clinically helpful.

  18. Computed tomography of radioactive objects and materials

    International Nuclear Information System (INIS)

    Sawicka, B.D.; Murphy, R.V.; Tosello, G.; Reynolds, P.W.; Romaniszyn, T.

    1990-01-01

    Computed tomography (CT) has been performed on a number of radioactive objects and materials. Several unique technical problems are associated with CT of radioactive specimens. These include general safety considerations, techniques to reduce background-radiation effects on CT images and selection criteria for the CT source to permit object penetration and to reveal accurate values of material density. In the present paper, three groups of experiments will be described, for objects with low, medium and high levels of radioactivity. CT studies on radioactive specimens will be presented. They include the following: (1) examination of individual ceramic reactor-fuel (uranium dioxide) pellets, (2) examination of fuel samples from the Three Mile Island reactor, (3) examination of a CANDU (CANada Deuterium Uranium: registered trademark) nuclear-fuel bundle which underwent a simulated loss-of-coolant accident resulting in high-temperature damage and (4) examination of a PWR nuclear-reactor fuel assembly. (orig.)

  19. System Matrix Analysis for Computed Tomography Imaging

    Science.gov (United States)

    Flores, Liubov; Vidal, Vicent; Verdú, Gumersindo

    2015-01-01

    In practical applications of computed tomography imaging (CT), it is often the case that the set of projection data is incomplete owing to the physical conditions of the data acquisition process. On the other hand, the high radiation dose imposed on patients is also undesired. These issues demand that high quality CT images can be reconstructed from limited projection data. For this reason, iterative methods of image reconstruction have become a topic of increased research interest. Several algorithms have been proposed for few-view CT. We consider that the accurate solution of the reconstruction problem also depends on the system matrix that simulates the scanning process. In this work, we analyze the application of the Siddon method to generate elements of the matrix and we present results based on real projection data. PMID:26575482

  20. Arterioportal shunts on dynamic computed tomography

    International Nuclear Information System (INIS)

    Nakayama, T.; Hiyama, Y.; Ohnishi, K.; Tsuchiya, S.; Kohno, K.; Nakajima, Y.; Okuda, K.

    1983-01-01

    Thirty-two patients, 20 with hepatocelluar carcinoma and 12 with liver cirrhosis, were examined by dynamic computed tomography (CT) using intravenous bolus injection of contrast medium and by celiac angiography. Dynamic CT disclosed arterioportal shunting in four cases of hepatocellular carcinoma and in one of cirrhosis. In three of the former, the arterioportal shunt was adjacent to a mass lesion on CT, suggesting tumor invasion into the portal branch. In one with hepatocellular carcinoma, the shunt was remote from the mass. In the case with cirrhosis, there was no mass. In these last two cases, the shunt might have been caused by prior percutaneous needle puncture. In another case of hepatocellular carcinoma, celiac angiography but not CT demonstrated an arterioportal shunt. Thus, dynamic CT was diagnostic in five of six cases of arteriographically demonstrated arterioportal shunts