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Sample records for underwent contrast-enhanced coronary

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

    Science.gov (United States)

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

    2014-01-01

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

  2. Contrast-Enhanced Whole-Heart Coronary MRA at 3T Using Interleaved EPI

    Science.gov (United States)

    Bhat, Himanshu; Yang, Qi; Zuehlsdorff, Sven; Li, Kuncheng; Li, Debiao

    2010-01-01

    Objectives The goal of this work was to reduce the scan time of contrast-enhanced whole-heart coronary magnetic resonance angiography (MRA) by using a gradient echo interleaved echo planar imaging (GRE-EPI) sequence at 3T field strength. Materials and Methods A GRE-EPI sequence was optimized to acquire contrast-enhanced whole-heart coronary MRA at 3T. First order phase correction was used for alignment of the odd and even echoes in the GRE-EPI echo train. Single and dual reference scan techniques for estimation of the linear phase correction parameters were evaluated using both phantom and volunteer studies. The GRE-EPI readout was combined with parallel imaging for a further reduction in scan time. To avoid image distortions, calibration signals for coil sensitivity estimation were acquired in a separate low resolution GRE scan prior to the whole-heart GRE-EPI scan. 8 healthy volunteers were scanned with the optimized contrast-enhanced GRE-EPI sequence. GRE-EPI images were acquired during slow infusion (0.3 ml/sec) of 0.1 mmol/kg body weight of Gd-BOPTA. For comparison purposes, the same 8 volunteers were scanned again in a separate scan session using a traditional GRE sequence with double the dose (0.2 mmol/kg body weight) of the same contrast agent with the same injection rate. The contrast-enhanced GRE-EPI and contrast-enhanced GRE techniques were compared in terms of relative SNR and CNR, image quality scores and visualized vessel lengths. Results Both, phantom and volunteer studies demonstrated that the dual reference scan phase correction technique was a key step for obtaining satisfactory image quality using GRE-EPI at 3T. Whole-heart coronary MRA with a spatial resolution of 1.0 × 1.0 × 2.0 mm3 was acquired with the GRE-EPI sequence in an average scan time of 2.5 ± 0.6 minutes, compared with 8.6 ± 2.7 minutes for the GRE technique. The GRE-EPI technique had lower relative CNR compared with the GRE sequence. The image quality and coronary artery

  3. Evaluation of the early enhancement of coronary atherosclerotic plaque by contrast-enhanced MR angiography

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    Li Tao [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Zhao Xihai [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Liu Xin [Paul C. Lauterbur Biomedical Imaging Center, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Science, Shenzhen 518067 (China); Gao Jianhua [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Zhao Shaohong [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Li Xin; Zhou Weihua [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Cai Zulong [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Zhang Weiguo [Cardiovascular and Neurological Consulting Institute, 6771 San Fernando, Irving, TX 75039 (United States); Yang Li, E-mail: Yangli301@yahoo.com [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China)

    2011-10-15

    Purpose: To evaluate the early enhancement of coronary atherosclerotic plaque using contrast-enhanced MR angiography (CE-MRA) and investigate the association between unstable angina pectoris (UAP) and early enhancement of the plaque. Methods: Forty-one patients presenting with angina pectoris and demonstrating single-vessel disease with non-calcified plaque and significant coronary stenosis ({>=}50%) on CTA were consecutively recruited for coronary CE-MRA. Contrast-to-noise ratio of the culprit plaque guided by CTA was measured on a cross-sectional multi-planar reconstruction image of the plaque on both pre- and post-CE-MRA. A 50% increasing of CNR was defined as plaque enhancement. The association between early enhancement of the plaques and UAP was analyzed. Results: Thirty-seven non-calcified plaques with significant coronary stenosis were detected in the 37 patients on MRA. 4 subjects were excluded because coronary atherosclerotic plaques were inadequate for identification on MRA. Of the 37 patients, 18 patients had UAP and other 19 patients presented stable angina pectoris (SAP). Of the 37 plaques on CE-MRA, 13 and 24 plaques presented early enhancement and no enhancement, respectively. Of the 13 early-enhanced plaques, 11 (85%) and 2 (15%) were found in the patients with UAP and SAP, respectively (p < 0.01). Of the 37 patients, 11 (61%) with UAP and 2 (11%) with SAP had early-enhanced plaques, respectively (p < 0.01). Conclusion: CE-MRA allows detection of early enhancement of coronary atherosclerotic plaque. The early enhancement is common in unstable angina and could be a sign of vulnerability.

  4. Correction of lumen contrast-enhancement influence on non-calcified coronary atherosclerotic plaque quantification on CT.

    Science.gov (United States)

    Kristanto, Wisnumurti; Tuncay, Volkan; Vliegenthart, Rozemarijn; van Ooijen, Peter M A; Oudkerk, Matthijs

    2015-02-01

    Lumen contrast-enhancement influences non-calcified atherosclerotic plaque Hounsfield-unit (HU) values in computed tomography (CT). This study aimed to construct and validate an algorithm to correct for this influence. Three coronary vessel phantoms with 1, 2, and 4 mm circular hollow lumina; with normal and plaque-infested walls were scanned simultaneously in oil using a dual-source CT scanner. Scanning was repeated as the lumina were alternately filled with water and four contrast solutions (100-400 HU, at 100 HU intervals). Images were reconstructed at 0.4 mm x-y pixel size. Pixel-by-pixel comparisons of contrast-enhanced and non-contrast-enhanced images confirmed exponential declining patterns in lumen contrast-enhancement influence on wall HU-values from the lumen border (y = Ae(-λx) + c). The median difference of the inside and outside 2-pixel radius part of the contrast-enhanced coronary phantom wall to the reference (non-contrast-enhanced images) was 45 and 2 HU, respectively. Based on the lumen contrast-enhancement influence patterns, a generalized correction algorithm was formulated. Application of the generalized correction algorithm to the inside 2-pixel radius part of the wall reduced the median difference to the reference to 4 HU. In conclusion, lumen contrast-enhancement influence on the vessel wall can be defined by an exponential approximation, allowing correction of the CT density of the vessel wall closest to the lumen. With this correction, a more accurate determination of vessel wall composition can be made.

  5. Correction of lumen contrast-enhancement influence on non-calcified coronary atherosclerotic plaque quantification on CT

    NARCIS (Netherlands)

    Kristanto, Wisnumurti; Tuncay, Volkan; Vliegenthart, Rozemarijn; van Ooijen, Peter M. A.; Oudkerk, Matthijs

    Lumen contrast-enhancement influences non-calcified atherosclerotic plaque Hounsfield-unit (HU) values in computed tomography (CT). This study aimed to construct and validate an algorithm to correct for this influence. Three coronary vessel phantoms with 1, 2, and 4 mm circular hollow lumina; with

  6. Prevalence of first-pass myocardial perfusion defects detected by contrast-enhanced dual-source CT in patients with non-ST segment elevation acute coronary syndromes

    Energy Technology Data Exchange (ETDEWEB)

    Schepis, Tiziano; Achenbach, Stephan; Marwan, Mohamed; Muschiol, Gerd; Ropers, Dieter; Daniel, Werner G.; Pflederer, Tobias [University of Erlangen, Department of Internal Medicine 2 (Cardiology), Erlangen (Germany)

    2010-07-15

    To investigate the prevalence and diagnostic value of first-pass myocardial perfusion defects (PD) visualised by contrast-enhanced multidetector computed tomography (MDCT) in patients admitted for a first acute coronary syndrome (ACS). Thirty-eight patients with non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina (UA) and scheduled for percutaneous coronary intervention underwent dual-source CT immediately before catheterisation. CT images were analysed for the presence of any PD by using a 17-segment model. Results were compared with peak cardiac troponin-I (cTnI) and angiography findings. PD were seen in 21 of the 24 patients with NSTEMI (median peak cTnI level 7.07 ng/mL; range 0.72-37.07 ng/mL) and in 2 of 14 patients with UA. PD corresponded with the territory of the infarct-related artery in 20 out of 22 patients. In a patient-based analysis, sensitivity, specificity, negative and positive predictive values of any PD for predicting NSTEMI were 88%, 86%, 80% and 91%. Per culprit artery, the respective values were 86%, 75%, 80% and 83%. In patients with non-ST segment elevation ACS, first-pass myocardial PD in contrast-enhanced MDCT correlate closely with the presence of myocardial necrosis, as determined by increases in cTnI levels. (orig.)

  7. A New Contrast Enhancement Protocol for Subtraction Coronary Computed Tomography Requiring a Short Breath-Holding Time.

    Science.gov (United States)

    Yamaguchi, Takayoshi; Ichikawa, Katsuhiro; Takahashi, Daichi; Sugaya, Teppei; Furuya, Jungo; Igarashi, Keiichi

    2017-01-01

    We have developed a new contrast enhancement protocol for subtraction coronary computed tomography (SCCTA) requiring a short breath-holding time. In the protocol, test and main boluses were sequentially and automatically injected, and correct timings for pre-contrast and contrast-enhanced scans for main bolus were automatically determined only by the test bolus tracking. Combined with a fixed short main bolus injection for 7 seconds, the breath-holding time was shortened as possible. The purpose of this study was to evaluate whether use of this new protocol produced adequate quality images, taking into account calcified lesions and in-stent lumens. Patients (n = 127) with calcium scores of >400 Agatston units or a history of stent placement were enrolled. Breath-holding times were recorded, and image quality was visually evaluated by two observers. The mean ± standard deviation breath-holding time was 13.2 ± 0.6 seconds. The mean ± SD computed tomography (CT) number of coronary arteries for the pre-contrast scan was sufficiently low [99.2 ± 32.2 Hounsfield units (HU)] and, simultaneously, that for SCCTA was 367.0 ± 77.2 HU. The rate of segments evaluated as unreadable was sufficiently low (3.8%). Use of the SCCTA protocol was efficient and allowed for a shorter breath-holding time and adequate diagnostic accuracy of SCCTA images, including images of calcified and stent implantation segments. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  8. Restoration of myocardial blood flow following percutaneous coronary balloon dilatation and stent implantation: Assessment with qualitative and quantitative contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Sensky, P.R.; Samani, N.J.; Horsfield, M.A.; Cherryman, G.R.

    2002-01-01

    AIM: To examine the serial use of magnetic resonance imaging (MRI) to evaluate regional myocardial perfusion changes following percutaneous coronary angioplasty and stent implantation (PTCA). MATERIALS AND METHODS: Six patients with single vessel coronary artery disease (CAD) underwent contrast-enhanced first pass MRI immediately prior to (visit A) and within 7 days after (visit B) PTCA. Three sequential short axis slices were obtained after gadodiamide (Gd) bolus (0.025 mmol/kg -1 ) at rest and during adenosine. Each short axis was divided radially into eight regions of interest (ROIs). ROIs were anatomically assigned to a coronary artery territory (CAT). Stress and rest qualitative and quantitative (unidirectional extraction fraction constant (K i ); index of myocardial perfusion reserve (MPRI) = stressK i / restK i ) perfusion parameters were determined for ROI supplied by remote and stenosed/stented vessels for each visit. RESULTS: In stented ROIs the number of ROIs demonstrating normal perfusion, as opposed to reversible perfusion deficits, increased. Qualitative perfusion assessment in remote CATs was unchanged. MPRI in stenotic CATs was lower than in remote CATs at visit A (P < 0.001). Following PTCA, MPRI increased in stented CATs (P < 0.001) but was unchanged in remote CATs. CONCLUSION: Restoration of myocardial perfusion following PTCA can be delineated with qualitative and quantitative perfusion MRI. Although at present the investigation is technically complex and not perfectly sensitive or specific, MRI has the potential to be a valuable tool for patient follow-up and evaluation of revascularization strategy efficacy. Sensky, P.R. et al. (2002)

  9. Non-calcified coronary atherosclerotic plaque visualization on CT : effects of contrast-enhancement and lipid-content fractions

    NARCIS (Netherlands)

    Kristanto, Wisnumurti; van Ooijen, Peter M. A.; Greuter, Marcel J. W.; Groen, Jaap M.; Vliegenthart, Rozemarijn; Oudkerk, Matthijs

    Computed tomography (CT) may characterize lipid-rich and presumably rupture-prone non-calcified coronary atherosclerotic plaque based on its Hounsfield-Unit (HU), but still inconclusively. This study aimed to evaluate factors influencing the HU-value of non-calcified plaque using software

  10. Diagnostic Accuracy of Detecting Hashimoto's Thyroiditis in Thyroid Cancer Patients Who Underwent Thyroid Surgery: Comparison of Ultrasonography, Positron Emission Tomography/CT, Contrast Enhanced CT, and Anti-Thyroid Antibody

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Gyun; Lee, Tae Hyun; Park, Dong Hee; Nam, Sang Been [Dept. of Radiology, Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    2012-11-15

    To compare the diagnostic accuracy of ultrasonography (US), F18-fluorodeoxyglucose positron emission tomography/CT (PET/CT), contrast enhanced CT (CECT), serum anti-thyroid antibody for detecting Hashimoto's thyroiditis in thyroid cancer patients who underwent neck surgery. A total of 150 patients with suspicious for thyroid cancer, who had previously undergone US guided needle aspiration of thyroid, were evaluated with the use of US, PET/CT, CECT and serum anti-thyroid antibody. The four studies were performed within two months before neck surgery. Hashimoto's thyroiditis was confirmed by histopathological results. The diagnostic accuracy of US, PET/CT, CECT and serum anti-thyroid antibody were calculated statistically. Hashimoto's thyroiditis was diagnosed in 51 out of the 150 patients, following neck surgery. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of US were 76.5%, 92.9%, 84.8%, 88.5%, and 87.3%, respectively. The corresponding values of PET/CT were 37.3%, 96.0%, 82.6%, 74.8%, and 76.0%, and CECT were 62.7%, 89.9%, 76.2%, 82.4%, and 80.7%, and serum anti-thyroid antibody level were 90.2%, 93.9%, 88.5%, 94.9%, and 92.7%, respectively. McNemar test revealed significant difference among PET/CT and others, but no significant differences among US, CECT and serum anti-thyroid antibody. Overall, serum anti-thyroid antibody showed most accurate diagnostic performance. In detecting Hashimoto's thyroiditis, serum anti-thyroid antibody showed higher diagnostic accuracy than others. US also showed relatively high diagnostic accuracy.

  11. Improved vessel morphology measurements in contrast-enhanced multi-detector computed tomography coronary angiography with non-linear post-processing

    International Nuclear Information System (INIS)

    Ferencik, Maros; Lisauskas, Jennifer B.; Cury, Ricardo C.; Hoffmann, Udo; Abbara, Suhny; Achenbach, Stephan; Karl, W. Clem; Brady, Thomas J.; Chan, Raymond C.

    2006-01-01

    Multi-detector computed tomography (MDCT) permits detection of coronary plaque. However, noise and blurring impair accuracy and precision of plaque measurements. The aim of the study was to evaluate MDCT post-processing based on non-linear image deblurring and edge-preserving noise suppression for measurements of plaque size. Contrast-enhanced MDCT coronary angiography was performed in four subjects (mean age 55 ± 5 years, mean heart rate 54 ± 5 bpm) using a 16-slice scanner (Siemens Sensation 16, collimation 16 x 0.75 mm, gantry rotation 420 ms, tube voltage 120 kV, tube current 550 mAs, 80 mL of contrast). Intravascular ultrasound (IVUS; 40 MHz probe) was performed in one vessel in each patient and served as a reference standard. MDCT vessel cross-sectional images (1 mm thickness) were created perpendicular to centerline and aligned with corresponding IVUS images. MDCT images were processed using a deblurring and edge-preserving noise suppression algorithm. Then, three independent blinded observers segmented lumen and outer vessel boundaries in each modality to obtain vessel cross-sectional area and wall area in the unprocessed MDCT cross-sections, post-processed MDCT cross-sections and corresponding IVUS. The wall area measurement difference for unprocessed and post-processed MDCT images relative to IVUS was 0.4 ± 3.8 mm 2 and -0.2 ± 2.2 mm 2 (p 2 , respectively. In conclusion, MDCT permitted accurate in vivo measurement of wall area and vessel cross-sectional area as compared to IVUS. Post-processing to reduce blurring and noise reduced variability of wall area measurements and reduced measurement bias for both wall area and vessel cross-sectional area

  12. Extent of myocardium at risk for left anterior descending artery, right coronary artery, and left circumflex artery occlusion depicted by contrast-enhanced steady state free precession and T2-weighted short tau inversion recovery magnetic resonance imaging

    DEFF Research Database (Denmark)

    Nordlund, David; Heiberg, Einar; Carlsson, Marcus

    2016-01-01

    Background - Contrast-enhanced steady state free precession (CE-SSFP) and T2-weighted short tau inversion recovery (T2-STIR) have been clinically validated to estimate myocardium at risk (MaR) by cardiovascular magnetic resonance while using myocardial perfusion single-photon emission computed...... tomography as reference standard. Myocardial perfusion single-photon emission computed tomography has been used to describe the coronary perfusion territories during myocardial ischemia. Compared with myocardial perfusion single-photon emission computed tomography, cardiovascular magnetic resonance offers...... superior image quality and practical advantages. Therefore, the aim was to describe the main coronary perfusion territories using CE-SSFP and T2-STIR cardiovascular magnetic resonance data in patients after acute ST-segment-elevation myocardial infarction. Methods and Results - CE-SSFP and T2-STIR data...

  13. Preliminary study of single contrast enhanced dual energy heart imaging using dual-source CT

    International Nuclear Information System (INIS)

    Peng Jin; Zhang Longjiang; Zhou Changsheng; Lu Guangming; Ma Yan; Gu Haifeng

    2009-01-01

    Objective: To evaluate the feasibility and preliminary applications of single contrast enhanced dual energy heart imaging using dual-source CT (DSCT). Methods: Thirty patients underwent dual energy heart imaging with DSCT, of which 6 cases underwent SPECT or DSA within one week. Two experienced radiologists assessed image quality of coronary arteries and iodine map of myocardium. and correlated the coronary artery stenosis with the perfusion distribution of iodine map. Results: l00% (300/300) segments reached diagnostic standards. The mean score of image for all patients was 4.68±0.57. Mural coronary artery was present in 10 segments in S cases, atherosclerotic plaques in 32 segments in 12 cases, of which 20 segments having ≥50% stenosis, 12 segments ≤50% stenosis; dual energy CT coronary angiography was consistent with the DSA in 3 patients. 37 segmental perfusion abnormalities on iodine map were found in 15 cases, including 28 coronary blood supply segment narrow segment and 9 no coronary stenosis (including three negative segments in SPECD. Conclusion: Single contrast enhanced dual energy heart imaging can provide good coronary artery and myocardium perfusion images in the patients with appropriate heart rate, which has a potential to be used in the clinic and further studies are needed. (authors)

  14. Prognostic Impact of the Geriatric Nutritional Risk Index on Long-Term Outcomes in Patients Who Underwent Percutaneous Coronary Intervention.

    Science.gov (United States)

    Wada, Hideki; Dohi, Tomotaka; Miyauchi, Katsumi; Doi, Shinichiro; Naito, Ryo; Konishi, Hirokazu; Tsuboi, Shuta; Ogita, Manabu; Kasai, Takatoshi; Hassan, Ahmed; Okazaki, Shinya; Isoda, Kikuo; Suwa, Satoru; Daida, Hiroyuki

    2017-06-01

    Malnutrition has been identified as an important predictor of poor clinical outcomes in patients with heart failure. The aim of this study is to examine the prognostic impact of nutritional status in patients with coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI). The impact of nutrition, assessed using the geriatric nutritional risk index (GNRI) calculated by serum albumin and body mass index, was evaluated in 2,853 patients with CAD who underwent their first PCI between 2000 and 2011. Patients were assigned to tertiles based on their GNRI levels. The incidences of all-cause death and cardiac death were assessed. The median GNRI values were 101 (interquartile range 95 to 106). Lower GNRI levels were associated with older age and higher prevalence of acute coronary syndrome and chronic kidney disease. During the median follow-up period of 7.4 years, Kaplan-Meier curves showed ongoing divergence in rates of mortality among tertiles (GNRI nutritional status was associated with long-term clinical outcomes in CAD patients after PCI. Evaluation of GNRI carries important prognostic information and may guide the therapeutic approach to such patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Long-term prognosis and clinical characteristics of young adults (≤40 years old) who underwent percutaneous coronary intervention.

    Science.gov (United States)

    Konishi, Hirokazu; Miyauchi, Katsumi; Kasai, Takatoshi; Tsuboi, Shuta; Ogita, Manabu; Naito, Ryo; Katoh, Yoshiteru; Okai, Iwao; Tamura, Hiroshi; Okazaki, Shinya; Daida, Hiroyuki

    2014-09-01

    Limited data exist regarding the long-term prognosis of percutaneous coronary intervention (PCI) in young adults. The aim of this study was to retrospectively assess the long-term clinical outcomes in young patients who underwent PCI. Between 1985 and 2011, 7649 consecutive patients underwent PCI, and data from 69 young adults (age ≤40 years) and 4255 old adults (age ≧65 years) were analyzed. A Cox proportional hazards regression analysis was used to determine the independent predictors of a composite endpoint that included all-cause death and acute coronary syndrome (ACS) during the follow-up period. The mean age of the 69 young patients was 36.1±4.9 years, and 96% of them were men. Approximately 30% were current smokers, and their body mass index (BMI) was 26.7±5.0kg/m(2). The prevalence of diabetes and hypertension was 33% and 48%, respectively. All patients had ≥1 conventional cardiovascular risk factor. At a median follow-up of 9.8 years, the overall death rate was 5.8%, and new-onset ACS occurred in 8.7%. Current smoking was an independent predictor of the composite endpoint (hazard ratio 4.46, confidence interval 1.08-19.1, p=0.04) for young adults. Current smoking and obesity (high BMI) are the important clinical characteristics in young Japanese coronary heart disease patients who undergo PCI. The long-term prognosis in young patients is acceptable, but current smoking is a significant independent predictor of death and the recurrence of ACS in young Japanese coronary heart disease patients who are obese. Copyright © 2014 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  16. Clinical Outcomes of patients with coronary artery disease who underwent FFR evaluation of intermediate coronary lesionS– COFFRS study

    Directory of Open Access Journals (Sweden)

    Srinivasa Prasad

    2017-07-01

    Conclusion: In our experience, MACE events were not higher in patients with FFR > 0.8 and kept under medical therapy and were similarly lower in patients with FFR ≤0.8 and underwent revascularisation (p = 0.73. Also MACE events were higher in patients with FFR ≤ 0.8 and did not undergo revascularisation compared to other two appropriately treated groups (p = 0.03. FFR based revascularization decision appears to be a safe strategy in Indian patients.

  17. Comparison of Standard Catheters Versus Radial Artery-Specific Catheter in Patients Who Underwent Coronary Angiography Through Transradial Access.

    Science.gov (United States)

    Chen, On; Goel, Sunny; Acholonu, Michael; Kulbak, Guy; Verma, Shivani; Travlos, Efstratios; Casazza, Richard; Borgen, Elliot; Malik, Bilal; Friedman, Michael; Moskovits, Norbert; Frankel, Robert; Shani, Jacob; Ayzenberg, Sergey

    2016-08-01

    In this prospective, randomized controlled study, we aim to compare the performance outcomes of standard catheters with the radial artery-specific catheter. Over the past decade, transradial cardiac catheterization has gained widespread popularity because of its low complication rates compared with transfemoral access. Operators have the choice of using either standard catheters (used for both transfemoral and transradial approach, with need for separate catheter use for either right or left coronary artery engagement) or a dedicated radial artery catheter, which is specifically designed to engage both coronary arteries through radial artery access. A total of 110 consecutive patients who underwent coronary angiography at our institution from March 2015 to April 2015 were prospectively randomized to either radial artery-specific Tiger catheter (5Fr; Terumo Interventional Systems, Somerset, New Jersey) versus standard Judkins left and right catheters (5Fr R4, L4; Cordis Corporation, Miami, Florida). The end points of the study included fluoroscopy time, dose-area product, contrast volume used, and total procedure time for the coronary angiography. A total of 57 patients (52%) were randomized to radial artery-specific catheter and 53 (48%) to the standard catheter. Tiger catheter was associated with significantly lower fluoroscopy time (184 ± 91 vs 238 ± 131 seconds, p = 0.015), which was statistically significant. Other outcome measures such as dose-area product (2,882.4 ± 1,471.2 vs 3,524.6 ± 2,111.7 Gy·cm(2), p = 0.07), total contrast volume (48.1 ± 16.1 vs 53.4 ± 18.5 ml, p = 0.114), and total procedure time (337 ± 382 vs 434 ± 137 seconds, p = 0.085) were also lower in single-catheter group, but it did not reach statistical significance. A total of 8 patients (14%) were crossed over from radial-specific catheter arm to standard catheter arm because of substandard image quality and difficulty in coronary engagement. Six patients had to be

  18. Improved predictive value of GRACE risk score combined with platelet reactivity for 1-year cardiovascular risk in patients with acute coronary syndrome who underwent coronary stent implantation.

    Science.gov (United States)

    Li, Shan; Liu, Hongbin; Liu, Jianfeng; Wang, Haijun

    2016-11-01

    Both high platelet reactivity (HPR) and Global Registry of Acute Coronary Events (GRACE) risk score have moderate predictive value for major adverse cardiovascular disease (CVD) events in patients with acute coronary syndrome (ACS) who underwent percutaneous coronary intervention (PCI), whereas the prognostic significance of GRACE risk score combined with platelet function testing remains unclear. A total of 596 patients with non-ST elevation ACS who underwent PCI were enrolled. The P2Y 12 reaction unit (PRU) value was measured by VerifyNow P2Y 12 assay and GRACE score was calculated by GRACE risk 2.0 calculator. Patients were stratified by a pre-specified cutoff value of PRU 230 and GRACE score 140 to assess 1-year risk of cardiovascular death, non-fatal myocardial infarction (MI), and stent thrombosis. Seventy-two (12.1%) patients developed CVD events during 1-year follow-up. Patients with CVD events had a higher PRU value (244.6 ± 50.9 vs. 203.7 ± 52.0, p risk independently. Compared to patients with normal platelet reactivity (NPR) and GRACE score risk (HR: 5.048; 95% CI: 2.268-11.237; p risk score yielded superior risk predictive capacity beyond GRACE score alone, which is shown by improved c-statistic value (0.871, p = 0.002) as well as net reclassification improvement (NRI 0.263, p risk of adverse CVD events. The combination of platelet function testing and GRACE score predicted 1-year CVD risk better.

  19. Contrast enhancement CT by iopamidol

    International Nuclear Information System (INIS)

    Mori, Masaki; Makita, Nobue; Yanai, Kyoko

    1984-01-01

    In order to evaluate the contrast enhancement effect and safety of iopamidol (IOP) in CT examination, IOP was compared with angiographin (AG). In the liver and abdominal aorta, peak CT values were obtained earlier and were higher in the group with AG than in the group with IOP. However, CT values in the group with IOP decreased a little more slowly than those in the group with AG. There was no significant difference in the effect on contrast enhancement between the groups. Intravenous injection of IOP caused lower degree of burning sensation than that of AG, and some of the patients with IOP did not feel burning sensation at all. Changes in clinical laboratory values were slight before and after intravenous injection of IOP. These results suggest that IOP is satisfactory in terms of safety and effect on contrast enhancement in CT examination. (Namekawa, K.)

  20. Preoperative evaluation of myocardial viability by thallium-201 imaging in patients with old myocardial infarction who underwent coronary revascularization

    International Nuclear Information System (INIS)

    Naruse, Hitoshi; Ohyanagi, Mitsumasa; Iwasaki, Tadaaki; Miyamoto, Takashi; Fukuchi, Minoru

    1992-01-01

    The myocardial uptake and redistribution in thallium scintigraphy and the regional wall motion by echocardiography were evaluated by a semi-quantitative method in 42 patients who previously had myocardial infarction (50 target vessels) and underwent coronary revascularization. The aim of this study was to elucidate the significance of the initial image, delayed image and redistribution on thallium-201 scintigraphy for clinical diagnosis of the myocardial viability. As a semi-quantitative analysis, we used a bull's-eye display for thallium image and centerline method for echocardiographic wall motion, and compared the results before and after revascularization. As a result, the thallium grade improved postoperatively in all 17 areas which preoperatively had showed redistribution, and also in 11 of the 32 areas without preoperative redistribution. The sensitivity, specificity and accuracy of preoperative thallium redistribution for predicting myocardial viability were 61%, 100% and 78%, respectively, when the postoperative improvement in the thallium grade was used as the standard. The postoperative probability of improvement in the thallium grade increased in proportion to the preoperative grade (delayed image)(p<0.01). There was no correlation between the preoperative thallium delayed image and postoperative improvement in wall motion. Postoperative improvement in thallium image and wall motion could not be predicted from the preoperative wall motion. Thus, postoperative improvement in thallium images can be anticipated if redistribution is present on the preoperative thallium image, and the preoperative thallium delayed image is useful for predicting myocardial viability. Improvement in wall motion could not be predicted preoperatively by these methods. (author)

  1. Prognostic factors for perioperative myocardial infarction and immediate mortality in patients who underwent coronary artery bypass graft surgery

    Directory of Open Access Journals (Sweden)

    Mirtha López Ramírez

    2016-03-01

    Conclusions: Older age and higher body mass index were protective prognostic factors for perioperative acute myocardial infarction events. Prolonged surgical time and complications were independently associated with perioperative infarction and mortality after coronary artery bypass graft surgery. Low preoperative glomerular filtration rate was also associated with mortality.

  2. Multiscale based adaptive contrast enhancement

    Science.gov (United States)

    Abir, Muhammad; Islam, Fahima; Wachs, Daniel; Lee, Hyoung

    2013-02-01

    A contrast enhancement algorithm is developed for enhancing the contrast of x-ray images. The algorithm is based on Laplacian pyramid image processing technique. The image is decomposed into three frequency sub-bands- low, medium, and high. Each sub-band contains different frequency information of the image. The detail structure of the image lies on the high frequency sub-band and the overall structure lies on the low frequency sub-band. Apparently it is difficult to extract detail structure from the high frequency sub-bands. Enhancement of the detail structures is necessary in order to find out the calcifications on the mammograms, cracks on any object such as fuel plate, etc. In our proposed method contrast enhancement is achieved from high and medium frequency sub-band images by decomposing the image based on multi-scale Laplacian pyramid and enhancing contrast by suitable image processing. Standard Deviation-based Modified Adaptive contrast enhancement (SDMACE) technique is applied to enhance the low-contrast information on the sub-bands without overshooting noise. An alpha-trimmed mean filter is used in SDMACE for sharpness enhancement. After modifying all sub-band images, the final image is derived from reconstruction of the sub-band images from lower resolution level to upper resolution level including the residual image. To demonstrate the effectiveness of the algorithm an x-ray of a fuel plate and two mammograms are analyzed. Subjective evaluation is performed to evaluate the effectiveness of the algorithm. The proposed algorithm is compared with the well-known contrast limited adaptive histogram equalization (CLAHE) algorithm. Experimental results prove that the proposed algorithm offers improved contrast of the x-ray images.

  3. Left ventricle size quantification using non-contrast-enhanced cardiac computed tomography--association with cardiovascular risk factors and coronary artery calcium score in the general population: The Heinz Nixdorf Recall Study.

    Science.gov (United States)

    Dykun, Iryna; Mahabadi, Amir A; Lehmann, Nils; Bauer, Marcus; Moebus, Susanne; Jöckel, Karl-Heinz; Möhlenkamp, Stefan; Erbel, Raimund; Kälsch, Hagen

    2015-08-01

    Increased left ventricular (LV) size is associated with cardiovascular mortality and morbidity. Once non-contrast cardiac computed tomography (CT) is performed for other purposes, information of LV size is readily available. To determine the association of gated CT-derived LV size with cardiovascular risk factors and coronary artery calcification (CAC) and to describe age- and gender-specific normative values in a general population cohort. LV area was quantified from non-contrast-enhanced CT in axial, end-diastolic images at a mid-ventricular slice in participants of the population-based Heinz Nixdorf Recall Study, free of known cardiovascular disease. LV index (LVI) was calculated by the quotient of LV area and body surface area (BSA). Crude and adjusted regression analyses were used to determine the association of LVI with risk factors and CAC. Overall, 3926 subjects (age 59 ± 8 years, 53% women) were included in this analysis. From quantification in end-diastolic phase, men had larger LV index (2232 ± 296 mm(2)/m(2) vs. 2088 ± 251 mm(2)/m(2), both P < 0.0001). LVI was strongly correlated systolic blood pressure (men, PE [95% CI]: 22.8 [15.5-30.2] mm(2)/10 mmHg; women, 23.4 [18.1-28.6]), and antihypertensive medication (men, 45.2 [14.7-75.8] mm(2); women: 46.5 [22.7-70.2], all P < 0.005). Cholesterol levels were associated with LVI in univariate analysis, however, correlations were low (R(2) ≤ 0.04). In multivariable regression, blood pressure, antihypertensive medication and cholesterol levels, remained associated with LVI (P < 0.05). LVI was linked with CAC in unadjusted (men, increase of CAC + 1 by 13.0% [1.4-25.8] with increased LVI by 1 standard deviation of LVI, P = 0.03; women, 20.7% [10.0-32.3], P < 0.0001) and risk factor adjusted models (men, 14.6% [3.7-26.6], P = 0.007); women, 17.4% [7.8-27.8], P = 0.0002). Non-contrast cardiac CT derived LV index is associated with body size and hypertension. LVI is weakly linked with CAC-score. Further studies

  4. Contrast-enhanced peripheral MRA

    DEFF Research Database (Denmark)

    Nielsen, Yousef W; Thomsen, Henrik S

    2012-01-01

    -state MRA. Gadolinium(Gd)-based contrast agents are used for CE-MRA of the peripheral arteries. Extracellular Gd agents have a pharmacokinetic profile similar to iodinated contrast media. Accordingly, these agents are employed for first-pass MRA. Blood-pool Gd-based agents are characterized by prolonged......In the last decade contrast-enhanced magnetic resonance angiography (CE-MRA) has gained wide acceptance as a valuable tool in the diagnostic work-up of patients with peripheral arterial disease. This review presents current concepts in peripheral CE-MRA with emphasis on MRI technique and contrast...... MRI contrast agent is injected intravenously and T1-weighted images are acquired in the subsequent arterial first-pass phase. In order to achieve high quality MR angiograms without interfering venous contamination or artifacts, a number of factors need to be taken into account. This includes magnetic...

  5. Contrast-enhanced endoscopic ultrasonography

    DEFF Research Database (Denmark)

    Reddy, Nischita K; Ioncică, Ana Maria; Săftoiu, Adrian

    2011-01-01

    Contrast agents are increasingly being used to characterize the vasculature in an organ of interest, to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures. We review the mechanisms of action of first, second and third generation contrast...... agents and their use in various endoscopic procedures in the gastrointestinal tract. Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy, assessment of depth of invasion of esophageal, gastric and gall bladder...... cancers and visualization of the portal venous system and esophageal varices. In addition, contrast agents can be used to differentiate pancreatic lesions. The use of color Doppler further increases the ability to diagnose and differentiate various pancreatic malignancies. The sensitivity of power Doppler...

  6. Contrast enhanced CT of spinal cord angioma

    International Nuclear Information System (INIS)

    Nakamura, Takahiko; Ebitani, Tsutomu; Honma, Takao; Sofue, Muroto; Nakamura, Shigeru

    1982-01-01

    Contrast enhanced CT on 6 patients with spinal cord angioma showed enhancement in 2 of them. The conditions to produce contrast enhancement were the window width of 100 - 200, and the window level of 0 - 50. In spinal cord angioma, contrast enhanced CT is presently only an adjunct to angiography and myelography. Nevertheless, contrast enhanced CT is useful in the screening test for spinal cord angioma, in the patients who are nonindicated to angiography, and in the postoperative follow-up. (Ueda, J.)

  7. Acute myocardial infarction in progressively elderly patients. A comparative analysis of immediate results in patients who underwent primary percutaneous coronary intervention

    Directory of Open Access Journals (Sweden)

    Luiz Alberto Mattos

    2001-01-01

    Full Text Available OBJECTIVE: Analysis of the in-hospital results, in progressively elderly patients who undergo primary percutaneous coronary intervention (PCI in the first 24 hours of AMI. METHODS: The patients were divided into three different age groups (60/69, 70/79, and > or = 80 years and were treated from 7/95 until 12/99. The primary success rate and the occurrence of major clinical events were analyzed at the end of the in-hospital phase. Coronary stent implantation and abciximab use were employed at the intervencionist discretion. RESULTS: We analyzed 201 patients with age ranging from 60 to 93 years, who underwent primary PCI. Patients with ages above 70 were more often female (p=.015. Those with ages above 80 were treated later with PCI (p=.054, and all of them presented with total occlusion of the infarct-related artery. Coronary stents were implanted in 30% of the patients. Procedural success was lower in > or = 80 year old patients (p=.022, and the death rate was higher in > or = 70 years olds (p=.019. Reinfarction and coronary bypass surgery were uncommon events. A trend occurred toward a higher combined incidence of major in-hospital events according to increased age (p=.064. CONCLUSION: Elderly patients ( > or = 70 years presented with adverse clinical and angiographic profiles and patients > or = 80 years of age obtained reduced TIMI 3 flow success rates after primary PTCA, and those > or = 70 years had a higher death rate.

  8. Acute myocardial infarction in progressively elderly patients. A comparative analysis of immediate results in patients who underwent primary percutaneous coronary intervention.

    Science.gov (United States)

    Mattos, L A; Zago, A; Chaves, A; Pinto, I; Tanajura, L; Staico, R; Centemero, M; Feres, F; Maldonado, G; Cano, M; Abizaid, A; Abizaid, A; Sousa, A G; Sousa, J E

    2001-01-01

    Analysis of the in-hospital results, in progressively elderly patients who undergo primary percutaneous coronary intervention (PCI) in the first 24 hours of AMI. The patients were divided into three different age groups (60/69, 70/79, and > or =80 years) and were treated from 7/95 until 12/99. The primary success rate and the occurrence of major clinical events were analyzed at the end of the in-hospital phase. Coronary stent implantation and abciximab use were employed at the interventionist discretion. We analyzed 201 patients with age ranging from 60 to 93 years, who underwent primary PCI. Patients with ages above 70 were more often female (p=.015). Those with ages above 80 were treated later with PCI (p=.054), and all of them presented with total occlusion of the infarct-related artery. Coronary stents were implanted in 30% of the patients. Procedural success was lower in > or =80 year old patients (p=.022), and the death rate was higher in > or =70 years olds (p=.019). Reinfarction and coronary bypass surgery were uncommon events. A trend occurred toward a higher combined incidence of major in-hospital events according to increased age (p=.064). Elderly patients (> or =70 years) presented with adverse clinical and angiographic profiles and patients > or =80 years of age obtained reduced TIMI 3 flow success rates after primary PTCA, and those > or =70 years had a higher death rate.

  9. Commercialization of vein contrast enhancement

    Science.gov (United States)

    Lovhoiden, Gunnar; Deshmukh, Harshal; Vrancken, Carlos; Zhang, Yong; Zeman, Herbert D.; Weinberg, Devin

    2003-07-01

    An ongoing clinical study of an experimental infrared (IR) device, the Vein Contrast Enhancer (VCE) that visualizes surface veins for medical access, indicates that a commercial device with the performance of the existing VCE would have significant clinical utility for even a very skilled phlebotomist. A proof-of-principle prototype VCE device has now been designed and constructed that captures IR images of surface veins with a commercial CCD camera, transfers the images to a PC for real-time software image processing to enhance the vein contrast, and projects the enhanced images back onto the skin with a modified commercial LCD projector. The camera and projector are mounted on precision slides allowing for precise mechanical alignment of the two optical axes and for measuring the effects of axes misalignment. Precision alignment of the captured and projected images over the entire field-of-view is accomplished electronically by software adjustments of the translation, scaling, and rotation of the enhanced images before they are projected back onto the skin. This proof-of-principle prototype will be clinically tested and the experience gained will lead to the development of a commercial device, OnTarget!, that is compact, easy to use, and will visualize accessible veins in almost all subjects needing venipuncture.

  10. Food pattern and quality of life in metabolic syndrome patients who underwent coronary artery bypass grafting in Taiwan.

    Science.gov (United States)

    Tung, Heng-Hsin; Tseng, Li-Hua; Wei, Jeng; Lin, Cheng-Hsin; Wang, Tsae-Jyy; Liang, Shu-Yuan

    2011-12-01

    Metabolic syndrome is associated with poor operative outcomes of coronary artery bypass grafting surgery (CABG). A healthy food pattern for metabolic syndrome patients is necessary not only in the initial stage to prevent cardiovascular disease but for those who experience cardiovascular problems and undergo heart surgery. Empirical studies that explore food pattern and quality of life metabolic syndrome patients who undergo CABG are lacking. Therefore, the objectives of this study are to explore the food pattern and quality of life of metabolic syndrome patients who undergo CABG and to examine the relationship between these two variables. A descriptive, correlational and cross section design was conducted. Through convenience sampling, 104 patients were recruited. Data were collected through three instruments: a demographic questionnaire; the Chinese Food Frequency Questionnaire-Short Form (Short C-FFQ), used to assess food pattern; and the Taiwanese version of the Medical Outcomes Study Short Form 36-Health Survey (SF-36), used to assess quality of life. Descriptive analysis, one-way analysis of variance (ANOVA) and Pearson correlation were used to analyze the data. The results indicated that patients who ate fruit more frequently tended to have a better quality of life, while the intake of fried food was more frequently associated with a poor quality of life. The use of these data gives the health care provider a better understanding of food pattern and their impact on quality of life in this population. Such an understanding can be used to develop targeted interventions to promote health in this and in other populations. Copyright © 2010 European Society of Cardiology. Published by Elsevier B.V. All rights reserved.

  11. Management of antithrombotic therapy in patients with coronary artery disease or atrial fibrillation who underwent abdominal surgical operations.

    Science.gov (United States)

    Schizas, Dimitrios; Kariori, Maria; Boudoulas, Konstantinos Dean; Siasos, Gerasimos; Patelis, Nikolaos; Kalantzis, Charalampos; Carmen-Maria, Moldovan; Vavuranakis, Manolis

    2018-04-02

    Patients treated with antithrombotic therapy that require abdominal surgical procedures has progressively increased overtime. The management of antithrombotics during both the peri- and post- operative period is of crucial importance. The goal of this review is to present current data concerning the management of antiplatelets in patients with coronary artery disease and of anticoagulants in patients with atrial fibrillation who had to undergo abdominal surgical operations. For this purpose, incidence of major adverse cardiovascular events (MACE) and risk of antithrombotic use during surgical procedures, as well as the recommendations based on recent guidelines were reported. A thorough search of PubMed, Scopus and the Cochrane Databases was conducted to identify randomized controlled trials, observational studies, novel current reviews, and ESC and ACC/AHA guidelines on the subject. Antithrombotic use in daily clinical practice results to two different pathways: reduction of thromboembolic risk, but a simultaneous increase of bleeding risk. This may cause a therapeutic dilemma during the perioperative period. Nevertheless, careless cessation of antithrombotics can increase MACE and thromboembolic events, however, maintenance of antithrombotic therapy may increase bleeding complications. Studies and current guidelines can assist clinicians in making decisions for the treatment of patients that undergo abdominal surgical operations while on antithrombotic therapy. Aspirin should not be stopped perioperatively in the majority of surgical operations. Determining whether to discontinue the use of anticoagulants before surgery depends on the surgical procedure. In surgical operations with a low risk for bleeding, oral anticoagulants should not be discontinued. Bridging therapy should only be considered in patients with a high risk of thromboembolism. Finally, patients with an intermediate risk for thromboembolism, management should be individualized according to patient

  12. Contrast-enhanced sonography in pancreatic diseases

    Energy Technology Data Exchange (ETDEWEB)

    Rickes, Steffen [Department of Internal Medicine, AMEOS Hospital GmbH, Halberstadt (Germany); Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke-University, Magdeburg (Germany)], E-mail: rickes@medkl.salvator-kh.de; Rauh, Peter; Uhle, Christine; Ensberg, Daniel [Department of Internal Medicine, AMEOS Hospital GmbH, Halberstadt (Germany); Moenkemueller, Klaus; Malfertheiner, Peter [Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke-University, Magdeburg (Germany)

    2007-11-15

    Contrast-enhanced sonography is a widely available imaging modality for the diagnosis of pancreatic diseases. With this procedure, pancreatic tumours can be differentiated better. Furthermore, contrast-enhanced sonography produces good results in the staging of acute pancreatitis severity, especially in the detection of pancreatic necrosis. In this review article the value of contrast-enhanced sonography in the diagnosis of pancreatic diseases will be described and discussed.

  13. Impact of high-density lipoprotein 3 cholesterol subfraction on periprocedural myocardial injury in patients who underwent elective percutaneous coronary intervention.

    Science.gov (United States)

    Harada, Kazuhiro; Kikuchi, Ryosuke; Suzuki, Susumu; Tanaka, Akihito; Aoki, Toshijiro; Iwakawa, Naoki; Kojima, Hiroki; Hirayama, Kenshi; Mitsuda, Takayuki; Sumi, Takuya; Negishi, Yosuke; Ishii, Hideki; Murohara, Toyoaki

    2018-02-02

    Periprocedural myocardial injury (PMI) is a major complication of percutaneous coronary intervention (PCI) and is associated with atherosclerotic coronary plaque and worse clinical outcomes. High-density lipoprotein cholesterol (HDL-C) is a protective factor for cardiovascular disease. However, the role of HDL-C subfractions, such as HDL2 cholesterol (HDL2-C) or HDL3 cholesterol (HDL3-C), in cardiovascular disease remains unclear. The purpose of the study was to investigate the relationship between HDL2-C and HDL3-C subfractions and the incidence of PMI in patients who underwent elective PCI. We enrolled 129 patients who underwent elective PCI for stable angina pectoris. PMI was defined as an increase in high-sensitivity troponin T levels > 5 times the upper normal limit (> 0.070 ng/mL) at 24 h after PCI. Serum HDL-C subfractions (HDL2-C and HDL3-C) were assessed using ultracentrifugation in patients with and those without PMI. HDL3-C levels were significantly lower in patients with PMI than in those without (15.1 ± 3.0 mg/dL vs. 16.4 ± 2.9 mg/dL, p = 0.016) and had an independent and inverse association with PMI (odds ratio, 0.86; 95% confidence interval, 0.74-0.99; p = 0.038). When divided by the cut-off value of HDL3-C for PMI (14.3 mg/dL), the incidence of PMI was significantly higher in low HDL3-C patients than in high HDL3-C patients (51.2% vs. 30.2%, p = 0.020). HDL3-C was an independent inverse predictor of PMI in patients who underwent elective PCI.

  14. A New Risk Factor Profile for Contrast-Induced Acute Kidney Injury in Patients Who Underwent an Emergency Percutaneous Coronary Intervention.

    Science.gov (United States)

    Yuan, Ying; Qiu, Hong; Song, Lei; Hu, Xiaoying; Luo, Tong; Zhao, Xueyan; Zhang, Jun; Wu, Yuan; Qiao, Shubin; Yang, Yuejin; Gao, Runlin

    2017-01-01

    We developed a new risk factor profile for contrast-induced acute kidney injury (CI-AKI) under a new definition in patients who underwent an emergency percutaneous coronary intervention (PCI). Consecutive patients (n = 1061) who underwent an emergency PCI were divided into a derivation group (n = 761) and a validation group (n = 300). The rates of CI-AKI were 23.5% (definition 1: serum creatinine [SCr] increase ≥25% in 72 hours), 4.3% (definition 2: SCr increase ≥44.2 μmol/L in 72 hours), and 7.0% (definition 3: SCr increase ≥44.2 μmol/L in 7 days). Due to the high sensitivity of definition 1 and the high rate of missed cases for late diagnosis of CI-AKI under definition 2, definition 3 was used in the study. The risk factor profile included body surface area 15.00 × 10 9 /L ( P = .047), estimated glomerular filtration rate 133 μmol/L ( P = .007), intra-aortic balloon pump application ( P = .006), and diuretics administration ( P < .001), showing a significant predictive power in the derivation group and validation group. The new risk factor profile of CI-AKI under a new CI-AKI definition in emergency PCI patients is easily applicable with a useful predictive value.

  15. Role of multi-slice CT coronary angiography in evaluating the different patterns of coronary artery disease in patients with unstable angina

    OpenAIRE

    Niazi, Gamal Eldine M.; Elia, Remon Z.

    2015-01-01

    Objective: To evaluate the different patterns of coronary artery disease among patients with unstable angina by the role of multislice CT coronary angiography. Patients and methods: From September 2013 to May 2014, 40 patients complaining from unstable angina showing initial negative ECG and troponin enzyme underwent a multi-slice CT coronary angiography. Each patient underwent a non-contrast scan to determine the calcium score, then a contrast enhanced ECG gated scan, then the obtained ax...

  16. Traços psicológicos dos pacientes submetidos a angioplastia transluminal coronária Psychological profile of patients that underwent coronary angioplasty

    Directory of Open Access Journals (Sweden)

    Lourdes Helena de Campos

    1990-12-01

    Full Text Available Este trabalho teve por objetivo a identificação de traços psicológicos e características emocionais comuns aos pacientes que foram, pela primeira vez, submetidos a angioplastia transluminal coronária (ATC, no Instituto Dante Pazzanese de Cardiologia. Foram analisados 84 pacientes, de ambros os sexos, com idade média de 55 anos. Foram realizadas, pela equipe de psicólogos, duas entrevistas semidirigidas, durante cada uma das quais foram aplicados o Inventário de Ansiedade Traço - Estado (IDATE e a Escala de Hamilton. Essas entrevistas foram realizadas imediatamente anterior à ATC e um dia após o procedimento, na alta dos pacientes. Os resultados permitiram-nos concluir que a grande maioria apresentou padrão comportamental tipo A, próprio do coronariano, alto estresse constitucional e ambiental e ansiedade - traço acima da média. Obtiveram alta porcentagem, também, as variáveis tensão, depressão, grau de competitividade e labilidade de humor.This paper presents psychological and emotional characteristics that were found common to patients that underwent a first coronary angioplasty at Instituto Dante Pazzanese de Cardiologia. We studied 84 patients of both sexes, with mean age of 55 years. Two semi-directed interviews were conducted by the psychology team, and during each of them the State-Trait - Anxiety Inventory STAI and the Hamilton Scale were applied. Such interviews were conducted immediately before PTCA and repeated one day after it, at patient's discharge. We concluded that most patients had a type A personality, typical of patients with coronary artey disease, high constitutional stress and anxiety-trace higher than the average population. There was also a high incidence of tension, depression, competitivity and humor lability.

  17. MRI contrast enhancement of malignant liver tumours following successful cryoablation

    Energy Technology Data Exchange (ETDEWEB)

    Shyn, Paul B.; Oliva, M.R.; Shah, Shaan H.; Tatli, Servet; Silverman, Stuart G. [Brigham and Women' s Hospital, Abdominal Imaging and Intervention, Department of Radiology, Boston, MA (United States); Catalano, Paul J. [Dana-Farber Cancer Institute, Department of Biostatistics and Computational Biology, Boston, MA (United States)

    2012-02-15

    To assess the incidence and degree of MRI contrast enhancement in liver tumours following successful percutaneous cryoablation. Thirty-eight patients with liver metastases (n = 29) or hepatocellular carcinoma (n = 9) underwent percutaneous cryoablation of 45 tumours between March 2004 and June 2009, with complete ablation zone coverage of the tumour and no local recurrence on follow-up imaging to date (range 3-60 months, mean 16). Contrast-enhanced MRI was used to assess 45 tumours at 24 h, 32 tumours at 2-4 months, and 21 tumours at 5-7 months. Percentage of tumours with contrast enhancement was assessed using dynamic spoiled gradient echo T1-weighted images. Twenty-four hours post-cryoablation, 23 out of 45 tumours (51%) enhanced compared with 42 out of 43 (98%) pre-ablation (p < 0.001). Mean percentage tumour enhancement decreased from 157% (range 26-745%) pre-ablation, to 107% (27-260%) at 24 h (p = 0.003), and 43% (24-103%) at 2-4 months (p < 0.001). The incidence and degree of tumour enhancement decreased through 5-7 months. Unlike previously reported studies of radiofrequency ablation, successful cryoablation of liver tumours is often associated with persistent tumour contrast enhancement on MRI performed at 24 h and decreasing over 2-7 months. (orig.)

  18. Contrast Enhanced US in the Abdomen

    International Nuclear Information System (INIS)

    Chung, Yong Eun; Kim, Ki Whang

    2012-01-01

    Contrast enhanced ultrasound, which was introduced in 1996, has been widely used in Europe and Eastern Asia. Ultrasound contrast agent can be classified as first generation and second generation, depending on the gas within the microbubble. With the first generation contrast agent, the high MI technique was used, and only intermittent scanning was possible due to destruction of the microbubble during scanning. Use of the second generation contrast agent with the low MI technique makes continuous scanning possible. Contrast enhanced US can be used in detection and differentiation of focal liver lesions. It is also helpful for monitoring of radiofrequency ablation and for targeting of US guided biopsy. Currently, because morphologic criteria alone may not reflect the response of the tumor to treatment, new criteria are needed for treatment evaluation after administration of anti-angiogenic agents. Contrast enhanced US could provide quantitative markers for evaluation of the response to treatment via use of dynamic contrast enhanced US. Due to cost-effectiveness, contrast enhanced US is not yet widely used in Korea; however, considering recent issues regarding contrast agent related adverse reaction, such as contrast induced nephropathy and nephrogenic systemic fibrosis, and radiation exposure, contrast enhanced US might be more widely used in Korea, as an alternative imaging modality in the future.

  19. Clinical impacts of inhibition of renin-angiotensin system in patients with acute ST-segment elevation myocardial infarction who underwent successful late percutaneous coronary intervention.

    Science.gov (United States)

    Park, Hyukjin; Kim, Hyun Kuk; Jeong, Myung Ho; Cho, Jae Yeong; Lee, Ki Hong; Sim, Doo Sun; Yoon, Nam Sik; Yoon, Hyun Ju; Hong, Young Joon; Kim, Kye Hun; Park, Hyung Wook; Kim, Ju Han; Ahn, Youngkeun; Cho, Jeong Gwan; Park, Jong Chun; Kim, Young Jo; Cho, Myeong Chan; Kim, Chong Jim

    2017-01-01

    Successful percutaneous coronary intervention (PCI) of the occluded infarct-related artery (IRA) in latecomers may improve long-term survival mainly by reducing left ventricular remodeling. It is not clear whether inhibition of renin-angiotensin system (RAS) brings additional better clinical outcomes in this specific population subset. Between January 2008 and June 2013, 669 latecomer patients with acute ST-segment elevation myocardial infarction (STEMI) (66.2±12.1 years, 71.0% males) in Korea Acute Myocardial Infarction Registry (KAMIR) who underwent a successful PCI were enrolled. The study population underwent a successful PCI for a totally occluded IRA. They were divided into two groups according to whether they were prescribed RAS inhibitors at the time of discharge: group I (RAS inhibition, n=556), and group II (no RAS inhibition, n=113). During the one-year follow-up, major adverse cardiac events (MACE), which consist of cardiac death and myocardial infarction, occurred in 71 patients (10.6%). There were significantly reduced incidences of MACE in the group I (hazard ratio=0.34, 95% confidence interval 0.199-0.588, p=0.001). In subgroup analyses, RAS inhibition was beneficial in patients with male gender, history of hypertension or diabetes mellitus, and even in patients with left ventricular ejection fraction (LVEF) ≥40%. In the baseline and follow-up echocardiographic data, benefit in changes of LVEF and left ventricular end-systolic volume was noted in group I. In latecomers with STEMI, RAS inhibition improved long-term clinical outcomes after a successful PCI, even in patients with low risk who had relatively preserved LVEF. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  20. Post-traumatic contrast enhancing brain lesion

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Jung; Kim, Hyun Sook; Jeong, Min Sun; Kim, Deok Ryeong; Cho, Young Kwon; Choi, Yun Sun [Eulji Hospital, Eulji University College of Medicine, Seoul (Korea, Republic of)

    2014-10-15

    Only a few studies have been reported on the MR contrast enhancement and the apparent diffusion coefficient (ADC) findings of the post-traumatic lesion of the brain. We report a case of the venous ischemia in the left frontal lobe observed in the MRI obtained one day after the incidence of trauma. Considering the presented slight increase in the ADC, the vasogenic edema was thought to be the major mechanism of the venous ischemia and excitotoxic injury. In spite of a slight increase in the ADC, the hyperintensity in the diffusion weighted imaging and contrast-enhanced areas eventually changed into hemorrhagic lesions.

  1. Outcome of Triple Antiplatelet Therapy Including Cilostazol in Elderly Patients with ST-Elevation Myocardial Infarction who Underwent Primary Percutaneous Coronary Intervention: Results from the INTERSTELLAR Registry.

    Science.gov (United States)

    Jang, Ho-Jun; Park, Sang-Don; Park, Hyun Woo; Suh, Jon; Oh, Pyung Chun; Moon, Jeonggeun; Lee, Kyounghoon; Kang, Woong Chol; Kwon, Sung Woo; Kim, Tae-Hoon

    2017-06-01

    Compared with dual antiplatelet therapy including aspirin and clopidogrel, triple antiplatelet therapy including cilostazol has a mortality benefit in patients with ST-segment elevation myocardial infarction. However, whether the mortality benefit persists in elderly patients is not clear. From 2007 to 2014, 1278 patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention were retrospectively analyzed. The patients were divided into four groups by age (elderly, respectively) and antiplatelet strategy (triple or dual antiplatelet therapy). We compared the mortality rates between the triple and dual antiplatelet therapy groups. There were 1052 (male, 85%; mean age, 56.3 ± 10.4 years) patients in the young group and 241 (male, 52.7%; mean age, 80.3 ± 4.5 years) patients in the elderly group. In the young and elderly groups, 220 (20.9%) and 28 (12.3%) patients were treated with triple antiplatelet therapy. During a 1-year follow-up period, 80 patients died (4.2% in the young group vs. 15.5% in the elderly group). Kaplan-Meier survival analysis revealed that triple antiplatelet therapy was associated with a lower mortality rate in the young group (log-rank, p = 0.005). Although there were more angiographic high-risk patients in the elderly group, similar mortality rates were reported (log-rank, p = 0.803) without increased bleeding rates (1 vs. 3.6% in the elderly group, p = 0.217). Triple antiplatelet therapy might be a better antiplatelet regimen than dual antiplatelet therapy for patients with ST-segment elevation myocardial infarction. Although this benefit was strong in patients aged elderly patients (aged ≥75 years).

  2. Predictive value of inflammatory factors on contrast-induced acute kidney injury in patients who underwent an emergency percutaneous coronary intervention.

    Science.gov (United States)

    Yuan, Ying; Qiu, Hong; Hu, Xiaoying; Luo, Tong; Gao, Xiaojin; Zhao, Xueyan; Zhang, Jun; Wu, Yuan; Qiao, Shubin; Yang, Yuejin; Gao, Runlin

    2017-09-01

    Contrast-induced acute kidney injury (CI-AKI) is one of the most serious complications in patients who undergo percutaneous coronary intervention (PCI), especially in those with acute coronary syndrome. It has been shown that inflammation may play an important role in the pathophysiology of CI-AKI. Inflammatory factors may play a predominant role in the prediction of CI-AKI in patients who undergo emergency PCI. Patients who underwent emergency PCI from 2013 to 2015 were consecutively enrolled and were divided into CI-AKI and non-CI-AKI groups. Logistic analysis was used to identify the risk factors of CI-AKI. Receiver operator characteristic curve analysis was performed to evaluate the area under the curve (AUC) and to establish the optimal cutoff. A total of 1061 patients were included, and the CI-AKI rate was 5.47% (58/1061). Logistic analysis showed that the white blood cell (WBC) count (odds ratio [OR]: 1.103, 95% confidence interval [CI]: 1.018-1.195, P = 0.016), neutrophil (N) count (OR: 1.134, 95% CI: 1.045-1.232, P = 0.003), neutrophil to lymphocyte ratio (NLR) (OR: 1.105, 95% CI: 1.044-1.169, P = 0.001), C-reactive protein (CRP) level (OR: 1.006, 95% CI: 1.001-1.011, P = 0.020), high-sensitivity C-reactive protein (hs-CRP) level (OR: 1.099, 95% CI: 1.020-1.184, P = 0.013), and big endothelin-1 (ET-1) level (OR: 4.030, 95% CI: 1.989-8.165, P < 0.001) were all significant predictors for CI-AKI, as was the left ventricular ejection fraction and diuretic administration. The AUC of the big ET-1 level was the highest (0.793, 95% CI: 0.733-0.853), followed by the NLR (0.708, 95% CI: 0.641-0.774), hs-CRP level (0.705, 95% CI: 0.627-0.782), CRP level (0.684, 95% CI: 0.607-0.761), N count (0.655, 95% CI: 0.584-0.726), WBC count (0.620, 95% CI: 0.544-0.695), and erythrocyte sedimentation rate (0.611, 95% CI: 0.527-0.695). The WBC count, N count, NLR, CRP level, hs-CRP level, and big ET-1 level are all associated with an increased risk of CI-AKI, and among which, the

  3. The 'humble' bubble: Contrast-enhanced ultrasound

    International Nuclear Information System (INIS)

    Marshall, Gill; Sykes, Anne; Berry, Jonathan; Jonker, Leon

    2011-01-01

    The use of contrast-enhanced ultrasound (CEUS) is increasing within the field of medical imaging. Ultrasonic contrast agent (UCA) contain gas microbubbles similar in size to red corpuscles which provide highly reflective interfaces, enabling dynamic demonstration of echogenic streams of the contrast within the anatomical area of interest on real-time grey scale ultrasound. Longevity of the microbubbles has been improved by changing their composition. The application of CEUS in the UK continues to grow, bringing it into territories historically occupied by computerised tomography (CT) scanning and magnetic resonance imaging (MRI). Hence, the role of CEUS may be of interest to all diagnostic imaging practitioners. Here we summarise the mode of action and use of CEUS, and its role within a range of applications. The potential risks of CEUS are compared to other contrast-enhanced imaging techniques. The benefits of CEUS and its implications for diagnostic imaging practice are also covered.

  4. Contrast-enhanced harmonic endoscopic ultrasound

    DEFF Research Database (Denmark)

    Săftoiu, A; Dietrich, C F; Vilmann, P

    2012-01-01

    Second-generation intravenous blood-pool ultrasound contrast agents are increasingly used in endoscopic ultrasound (EUS) for characterization of microvascularization, differential diagnosis of benign and malignant focal lesions, and improving staging and guidance of therapeutic procedures. Although...... initially used as Doppler signal enhancers, second-generation microbubble contrast agents are now used with specific contrast harmonic imaging techniques, which benefit from the highly nonlinear behavior of the microbubbles. Contrast-specific modes based on multi-pulse technology are used to perform...... contrast-enhanced harmonic EUS based on a very low mechanical index (0.08 - 0.12). Quantification techniques based on dynamic contrast-enhanced ultrasound have been recommended for perfusion imaging and monitoring of anti-angiogenic treatment, mainly based on time-intensity curve analysis. Most...

  5. Contrast enhancing techniques in digital holographic microscopy

    International Nuclear Information System (INIS)

    Lobera, J; Coupland, J M

    2008-01-01

    A digital holographic microscope (DHM) can be considered as a microscope with an extended depth of field. From a single DHM recording the propagating component of the scattered field can be reconstructed in three dimensions (3D). As in conventional white light microscopy contrasting enhancing techniques can be applied to highlight characteristics of interest. If these techniques are used to enhance the reconstruction from a DHM, then it is important to understand the characteristics of these techniques in 3D. In this paper the performance of phase contrast, differential interference contrast, Hoffman and spiral phase contrast visualization methods are discussed in 3D

  6. Contrast enhancement of mail piece images

    Science.gov (United States)

    Shin, Yong-Chul; Sridhar, Ramalingam; Demjanenko, Victor; Palumbo, Paul W.; Hull, Jonathan J.

    1992-08-01

    A New approach to contrast enhancement of mail piece images is presented. The contrast enhancement is used as a preprocessing step in the real-time address block location (RT-ABL) system. The RT-ABL system processes a stream of mail piece images and locates destination address blocks. Most of the mail pieces (classified into letters) show high contrast between background and foreground. As an extreme case, however, the seasonal greeting cards usually use colored envelopes which results in reduced contrast osured by an error rate by using a linear distributed associative memory (DAM). The DAM is trained to recognize the spectra of three classes of images: with high, medium, and low OCR error rates. The DAM is not forced to make a classification every time. It is allowed to reject as unknown a spectrum presented that does not closely resemble any that has been stored in the DAM. The DAM was fairly accurate with noisy images but conservative (i.e., rejected several text images as unknowns) when there was little ground and foreground degradations without affecting the nondegraded images. This approach provides local enhancement which adapts to local features. In order to simplify the computation of A and (sigma) , dynamic programming technique is used. Implementation details, performance, and the results on test images are presented in this paper.

  7. Quantitative analysis of infrared contrast enhancement algorithms

    Science.gov (United States)

    Weith-Glushko, Seth; Salvaggio, Carl

    2007-04-01

    Dynamic range reduction and contrast enhancement are two image-processing methods that are required when developing thermal camera systems. The two methods must be performed in such a way that the high dynamic range imagery output from current sensors are compressed in a pleasing way for display on lower dynamic range monitors. This research examines a quantitative analysis of infrared contrast enhancement algorithms found in literature and developed by the author. Four algorithms were studied, three of which were found in literature and one developed by the author: tail-less plateau equalization (TPE), adaptive plateau equalization (APE), the method according to Aare Mällo (MEAM), and infrared multi-scale retinex (IMSR). TPE and APE are histogram-based methods, requiring the calculation of the probability density of digital counts within an image. MEAM and IMSR are frequency-domain methods, methods that operate on input imagery that has been split into components containing differing spatial frequency content. After a rate of growth analysis and psychophysical trial were performed, MEAM was found to be the best algorithm.

  8. Contrast enhanced ultrasound of sentinel lymph nodes

    Directory of Open Access Journals (Sweden)

    XinWu Cui

    2013-03-01

    Full Text Available Sentinel lymph nodes are the first lymph nodes in the region that receive lymphatic drainage from a primary tumor. The detection or exclusion of sentinel lymph node micrometastases is critical in the staging of cancer, especially breast cancer and melanoma because it directly affects patient’s prognosis and surgical management. Currently, intraoperative sentinel lymph node biopsies using blue dye and radioisotopes are the method of choice for the detection of sentinel lymph node with high identification rate. In contrast, conventional ultrasound is not capable of detecting sentinel lymph nodes in most cases. Contrast enhanced ultrasound with contrast specific imaging modes has been used for the evaluation and diagnostic work-up of peripherally located suspected lymphadenopathy. The method allows for real-time analysis of all vascular phases and the visualization of intranodal focal “avascular” areas that represent necrosis or deposits of neoplastic cells. In recent years, a number of animal and human studies showed that contrast enhanced ultrasound can be also used for the detection of sentinel lymph node, and may become a potential application in clinical routine. Several contrast agents have been used in those studies, including albumin solution, hydroxyethylated starch, SonoVue®, Sonazoid® and Definity®. This review summarizes the current knowledge about the use of ultrasound techniques in detection and evaluation of sentinel lymph node.

  9. Osteoblastic Metastases Mimickers on Contrast Enhanced CT

    Directory of Open Access Journals (Sweden)

    Fahad Al-Lhedan

    2017-01-01

    Full Text Available Secondary osseous involvement in lymphoma is more common compared to primary bone lymphoma. The finding of osseous lesion can be incidentally discovered during the course of the disease. However, osseous metastases are infrequently silent. Detection of osseous metastases is crucial for accurate staging and optimal treatment planning of lymphoma. The aim of imaging is to identify the presence and extent of osseous disease and to assess for possible complications such as pathological fracture of the load-bearing bones and cord compression if the lesion is spinal. We are presenting two patients with treated lymphoma who were in complete remission. On routine follow-up contrast enhanced CT, there were new osteoblastic lesions in the spine worrisome for metastases. Additional studies were performed for further evaluation of both of them which did not demonstrate any corresponding suspicious osseous lesion. The patients have a prior history of chronic venous occlusive thrombosis that resulted in collaterals formation. Contrast enhancement of the vertebral body marrow secondary to collaterals formation and venous flow through the vertebral venous plexus can mimic the appearance of spinal osteoblastic metastases.

  10. MRI contrast enhancement using Magnetic Carbon Nanoparticles

    Science.gov (United States)

    Chaudhary, Rakesh P.; Kangasniemi, Kim; Takahashi, Masaya; Mohanty, Samarendra K.; Koymen, Ali R.; Department of Physics, University of Texas at Arlington Team; University of Texas Southwestern Medical Center Team

    2014-03-01

    In recent years, nanotechnology has become one of the most exciting forefront fields in cancer diagnosis and therapeutics such as drug delivery, thermal therapy and detection of cancer. Here, we report development of core (Fe)-shell (carbon) nanoparticles with enhanced magnetic properties for contrast enhancement in MRI imaging. These new classes of magnetic carbon nanoparticles (MCNPs) are synthesized using a bottom-up approach in various organic solvents, using the electric plasma discharge generated in the cavitation field of an ultrasonic horn. Gradient echo MRI images of well-dispersed MCNP-solutions (in tube) were acquired. For T2 measurements, a multi echo spin echo sequence was performed. From the slope of the 1/T2 versus concentration plot, the R2 value for different CMCNP-samples was measured. Since MCNPs were found to be extremely non-reactive, and highly absorbing in NIR regime, development of carbon-based MRI contrast enhancement will allow its simultaneous use in biomedical applications. We aim to localize the MCNPs in targeted tissue regions by external DC magnetic field, followed by MRI imaging and subsequent photothermal therapy.

  11. Characteristics of hypertrophic cardiomyopathy on delayed contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Yan Chaowu; Zhao Shihua; Li Hua; Jiang Shiliang; Lu Minjie; Zhang Yan; Wei Yunqing; Ling Jian; Fang Wei

    2010-01-01

    Objective: To analyze the characteristics of hypertrophic cardiomyopathy (HCM) on delayed contrast-enhanced cardiac magnetic resonance imaging (CMRI). Methods: All patients underwent delayed contrast-enhanced CMRI. The left ventricle was divided into 9 segments to assess the location, extent and function of the hypertrophic segments. The t test was applied for the statistics. Results: Of 154 patients, delayed enhancement of' hypertrophic segment was found in 95 cases and non-delayed enhancement in 59 cases. The thickness and number of hypertrophic segment in patients with delayed enhancement were larger than those with non-delayed enhancement [(24.8±5.5) mm vs (20.4± 3.8) mm, t=3.82, P<0.05; (3.3±1.9) vs (2.4±1.7), t=2.26, P<0.05], and the age was younger [(46.0±15.2) years vs (55.0±11.9) years, t=-3.67, P<0.05]. The diffuse enhancement was found in 62 patients, and confluent enhancement in 33 patients. Confluent enhancement was found in all 14 patients after the alcohol ablation procedure. Conclusion: The age, thickness and number of hypertrophic segments in patients with delayed enhancement are different from those with non-delayed enhancement. (authors)

  12. Preparative fasting for contrast-enhanced CT: reconsideration.

    Science.gov (United States)

    Lee, Bae-Young; Ok, Jin-Ju; Abdelaziz Elsayed, Abdelrahman Adel; Kim, Youngjin; Han, Dae Hee

    2012-05-01

    To evaluate the evidence on the value of preparative fluid fasting for patients undergoing elective computed tomography (CT) with intravenous administration of contrast material and to survey leading institutions in a number of countries on their current policies in this regard. This study qualified for exempt status by the institutional review board. First, 20 keyword combinations were entered into Medline to ascertain the correlation between fluid ingestion preceding contrast material-enhanced CT and development of aspiration pneumonia. The numbers of patients were summed up to estimate incidence of aspiration pneumonia attributable to ingestion of clear inert fluid before contrast-enhanced CT examination. Second, a multinational survey was conducted about the length of preparative fasting protocols, if any, for fluids and solids that they recommend to patients before elective non-gastrointestinal contrast-enhanced CT. Aspiration was not noted in any of 2001 patients (13 studies in the literature) who underwent contrast-enhanced CT after fluid ingestion. Data were available from 69 (86.3%) of 80 institutions queried (17 Korean, 14 U.S., 11 French, 10 Australian, 10 German, and seven Egyptian hospitals). Two-thirds (14 of 21 [66.7%]) of the French and German hospitals had a no-restriction policy for both fluids and solids, while Australian hospitals had a policy liberal about fluids (no restrictions in eight of 10 [80%]) only. Policies on fluids were variable in Korea, the United States, and Egypt (restrictions of 0-8 hours, 0-4 hours, and 0-6 hours, respectively), as were policies on solids in Korea, the United States, Australia, and Egypt (restrictions of 0-8 hours, 0-6 hours, 0 to 4-6 hours, and 0 hours to overnight, respectively). The length of fasting was longer for solids than for fluids in 20 hospitals. There is little evidence that ingestion of clear inert fluid prior to contrast-enhanced CT is a cause of aspiration pneumonia; the length of fasting is

  13. International guidelines for contrast-enhanced ultrasonography

    DEFF Research Database (Denmark)

    Nolsøe, Christian Pállson; Lorentzen, Torben

    2016-01-01

    The intent of this review is to discuss and comment on common clinical scenarios in which contrast-enhanced ultrasonography (CEUS) may play a decisive role and to illustrate important points with typical cases. With the advent of CEUS, the scope of indications for ultrasonography has been dramati...... thirds of the global population may receive no such care. Ultrasound imaging with CEUS has the potential to correct this inequity....... dramatically extended, and now includes functional imaging and tissue characterization, which in many cases enable tumor diagnosis without a biopsy. It is virtually impossible to imagine the practice of modern medicine as we know it in high-income countries without the use of imaging, and yet, an estimated two...

  14. Fast mutual-information-based contrast enhancement

    Science.gov (United States)

    Cao, Gang; Yu, Lifang; Tian, Huawei; Huang, Xianglin; Wang, Yongbin

    2017-07-01

    Recently, T. Celik proposed an effective image contrast enhancement (CE) method based on spatial mutual information and PageRank (SMIRANK). According to the state-of-the-art evaluation criteria, it achieves the best visual enhancement quality among existing global CE methods. However, SMIRANK runs much slower than the other counterparts, such as histogram equalization (HE) and adaptive gamma correction. Low computational complexity is also required for good CE algorithms. In this paper, we novelly propose a fast SMIRANK algorithm, called FastSMIRANK. It integrates both spatial and gray-level downsampling into the generation of pixel value mapping function. Moreover, the computation of rank vectors is speeded up by replacing PageRank with a simple yet efficient row-based operation of mutual information matrix. Extensive experimental results show that the proposed FastSMIRANK could accelerate the processing speed of SMIRANK by about 20 times, and is even faster than HE. Comparable enhancement quality is preserved simultaneously.

  15. Contrast-enhanced magnetic resonance angiography

    International Nuclear Information System (INIS)

    Vogl, T.J.; Hoffmann, Y.; Muehler, A.; Felix, R.

    1994-01-01

    Magnetic resonance angiography (MRA) protocols are based on standard sequence protocols like time of flight MRA, which evaluates inflowing spins. This technique is limited by a variety of artifacts like the saturation artifact via turbulent blood flow. Contrast media diminish these artifacts like extracellular agents and blood-pool contrast media. The clinical value of the contrast-enhanced MRA for cerebral pathologies is based on the use of the paramagnetic contrast agent Gd-DTPA. For extracerebral diseases this technique is restricted because of the simultaneous visualization of both arterial and venous vascular territorities. Occult venous sinus thrombosis or AV malformations are clinical essential indications for the use of C-MRA. Experimental data prove the excellent contrast abilities of blood-pool agents like Gd-DTPA-polylysin or Gd-DTPA-albumin, which demonstrate long intravascular persistence and retarded excretion. (orig.) [de

  16. Dynamic contrast-enhanced magnetic resonance imaging of the wrist in children with juvenile idiopathic arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Nusman, Charlotte M. [Emma Children' s Hospital, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Academic Medical Center, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Lavini, Cristina; Hemke, Robert; Caan, Matthan W.A.; Maas, Mario [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Schonenberg-Meinema, Dieneke; Berg, J.M. van den; Kuijpers, Taco W. [Emma Children' s Hospital, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Academic Medical Center, Amsterdam (Netherlands); Dolman, Koert M. [Sint Lucas Andreas Hospital, Department of Pediatrics, Amsterdam (Netherlands); Reade Institute location Jan van Breemen, Department of Pediatric Rheumatology, Amsterdam (Netherlands); Rossum, Marion A.J. van [Reade Institute location Jan van Breemen, Department of Pediatric Rheumatology, Amsterdam (Netherlands); Emma Children' s Hospital, Department of Pediatrics, Academic Medical Center, Amsterdam (Netherlands)

    2017-02-15

    Dynamic contrast-enhanced MRI provides information on the heterogeneity of the synovium, the primary target of disease in children with juvenile idiopathic arthritis (JIA). To evaluate the feasibility of dynamic contrast-enhanced MRI in the wrist of children with JIA using conventional descriptive measures and time-intensity-curve shape analysis. To explore the association between enhancement characteristics and clinical disease status. Thirty-two children with JIA and wrist involvement underwent dynamic contrast-enhanced MRI with movement-registration and were classified using validated criteria as clinically active (n = 27) or inactive (n = 5). Outcome measures included descriptive parameters and the classification into time-intensity-curve shapes, which represent the patterns of signal intensity change over time. Differences in dynamic contrast-enhanced MRI outcome measures between clinically active and clinically inactive disease were analyzed and correlation with the Juvenile Arthritis Disease Activity Score was determined. Comprehensive evaluation of disease status was technically feasible and the quality of the dynamic dataset was improved by movement registration. The conventional descriptive measure maximum enhancement differed significantly between clinically active and inactive disease (P = 0.019), whereas time-intensity-curve shape analysis showed no differences. Juvenile Arthritis Disease Activity Score correlated moderately with enhancing volume (P = 0.484). Dynamic contrast-enhanced MRI is a promising biomarker for evaluating disease status in children with JIA and wrist involvement. Conventional descriptive dynamic contrast-enhanced MRI measures are better associated with clinically active disease than time-intensity-curve shape analysis. (orig.)

  17. Perceptual Contrast Enhancement with Dynamic Range Adjustment.

    Science.gov (United States)

    Zhang, Hong; Li, Yuecheng; Chen, Hao; Yuan, Ding; Sun, Mingui

    2013-12-01

    Recent years, although great efforts have been made to improve its performance, few Histogram equalization (HE) methods take human visual perception (HVP) into account explicitly. The human visual system (HVS) is more sensitive to edges than brightness. This paper proposes to take use of this nature intuitively and develops a perceptual contrast enhancement approach with dynamic range adjustment through histogram modification. The use of perceptual contrast connects the image enhancement problem with the HVS. To pre-condition the input image before the HE procedure is implemented, a perceptual contrast map (PCM) is constructed based on the modified Difference of Gaussian (DOG) algorithm. As a result, the contrast of the image is sharpened and high frequency noise is suppressed. A modified Clipped Histogram Equalization (CHE) is also developed which improves visual quality by automatically detecting the dynamic range of the image with improved perceptual contrast. Experimental results show that the new HE algorithm outperforms several state-of-the-art algorithms in improving perceptual contrast and enhancing details. In addition, the new algorithm is simple to implement, making it suitable for real-time applications.

  18. Dynamic contrast enhanced MRI in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Alonzi, Roberto [Marie Curie Research Wing, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, Middlesex, HA6 2RN (United Kingdom)], E-mail: robertoalonzi@btinternet.com; Padhani, Anwar R. [Paul Strickland Scanner Centre, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, Middlesex, HA6 2RN (United Kingdom); Synarc Inc. 575 Market Street, San Francisco, CA 94105 (United States)], E-mail: anwar.padhani@paulstrickland-scannercentre.org.uk; Allen, Clare [Department of Imaging, University College Hospital, London, 235 Euston Road, NW1 2BU (United Kingdom)], E-mail: clare.allen@uclh.nhs.uk

    2007-09-15

    Angiogenesis is an integral part of benign prostatic hyperplasia (BPH), is associated with prostatic intraepithelial neoplasia (PIN) and is key to the growth and for metastasis of prostate cancer. Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) using small molecular weight gadolinium chelates enables non-invasive imaging characterization of tissue vascularity. Depending on the technique used, data reflecting tissue perfusion, microvessel permeability surface area product, and extracellular leakage space can be obtained. Two dynamic MRI techniques (T{sub 2}*-weighted or susceptibility based and T{sub 1}-weighted or relaxivity enhanced methods) for prostate gland evaluations are discussed in this review with reference to biological basis of observations, data acquisition and analysis methods, technical limitations and validation. Established clinical roles of T{sub 1}-weighted imaging evaluations will be discussed including lesion detection and localisation, for tumour staging and for the detection of suspected tumour recurrence. Limitations include inadequate lesion characterisation particularly differentiating prostatitis from cancer, and in distinguishing between BPH and central gland tumours.

  19. Dynamic Contrast-Enhanced MRI of Cervical Cancers: Temporal Percentile Screening of Contrast Enhancement Identifies Parameters for Prediction of Chemoradioresistance

    International Nuclear Information System (INIS)

    Andersen, Erlend K.F.; Hole, Knut Håkon; Lund, Kjersti V.; Sundfør, Kolbein; Kristensen, Gunnar B.; Lyng, Heidi; Malinen, Eirik

    2012-01-01

    Purpose: To systematically screen the tumor contrast enhancement of locally advanced cervical cancers to assess the prognostic value of two descriptive parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Methods and Materials: This study included a prospectively collected cohort of 81 patients who underwent DCE-MRI with gadopentetate dimeglumine before chemoradiotherapy. The following descriptive DCE-MRI parameters were extracted voxel by voxel and presented as histograms for each time point in the dynamic series: normalized relative signal increase (nRSI) and normalized area under the curve (nAUC). The first to 100th percentiles of the histograms were included in a log-rank survival test, resulting in p value and relative risk maps of all percentile–time intervals for each DCE-MRI parameter. The maps were used to evaluate the robustness of the individual percentile–time pairs and to construct prognostic parameters. Clinical endpoints were locoregional control and progression-free survival. The study was approved by the institutional ethics committee. Results: The p value maps of nRSI and nAUC showed a large continuous region of percentile–time pairs that were significantly associated with locoregional control (p < 0.05). These parameters had prognostic impact independent of tumor stage, volume, and lymph node status on multivariate analysis. Only a small percentile–time interval of nRSI was associated with progression-free survival. Conclusions: The percentile–time screening identified DCE-MRI parameters that predict long-term locoregional control after chemoradiotherapy of cervical cancer.

  20. FDG-PET/contrast-enhanced CT as a post-treatment tool in head and neck squamous cell carcinoma: comparison with FDG-PET/non-contrast-enhanced CT and contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Suenaga, Yuko; Kitajima, Kazuhiro; Sugimura, Kazuro [Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Ishihara, Takeaki; Sasaki, Ryohei [Kobe University Graduate, School of Medicine, Department of Radiology, Division of Radiation Oncology, Kobe (Japan); Otsuki, Naoki; Nibu, Ken-ichi [Kobe University Graduate, School of Medicine, Department of Otolaryngology-Head and Neck Surgery, Kobe (Japan); Minamikawa, Tsutomu [Kobe University Graduate School of Medicine, Department of Oral and Maxillofacial Surgery, Kobe (Japan); Kiyota, Naomi [Kobe University Hospital, Department of Medical Oncology and Hematology, Kobe (Japan)

    2016-04-15

    To evaluate the accuracy of PET/CT using {sup 18}F-fluorodeoxyglucose (FDG) with IV contrast for suspected recurrent head and neck squamous cell carcinoma (HNSCC). One hundred and seventy patients previously treated for HNSCC underwent PET/CT, consisting of non-contrast-enhanced and contrast-enhanced CT, to investigate suspected recurrence. Diagnostic performance of PET/contrast-enhanced CT (PET/ceCT), PET/non-contrast-enhanced CT (PET/ncCT) and contrast-enhanced CT (ceCT) for local or regional recurrence, distant metastasis, overall recurrence and second primary cancer was evaluated. The reference standard included histopathology, treatment change and imaging follow-up. The patient-based areas under the receiver operating characteristic curves (AUC) for ceCT, PET/ncCT and PET/ceCT were 0.82, 0.96 and 0.98 for local recurrence, 0.73, 0.86 and 0.86 for regional recurrence, 0.86, 0.91 and 0.92 for distant metastasis, 0.72, 0.86 and 0.87 for overall recurrence, and 0.86, 0.89 and 0.91 for a second primary cancer. Both PET/ceCT and PET/ncCT statistically showed larger AUC than ceCT for recurrence, and the difference between PET/ceCT and PET/ncCT for local recurrence reached a significant level (p = 0.039). The accuracy of PET/ceCT for diagnosing overall recurrence was high, irrespective of the time interval after the last treatment (83.3-94.1 %). FDG-PET/CT was a more accurate HNSCC restaging tool than ceCT. The added value of ceCT at FDG-PET/CT is minimal. (orig.)

  1. Survey of Contrast Enhancement Techniques based on Histogram Equalization

    OpenAIRE

    Manpreet Kaur,; Jasdeep Kaur; Jappreet Kaur

    2011-01-01

    This Contrast enhancement is frequently referred to as one of the most important issues in image processing. Histogram equalization (HE) is one of the common methods used for improving contrast in digital images. Histogram equalization (HE) has proved to be a simple and effective image contrast enhancement technique. However, the conventional histogram equalization methods usually result in excessive contrast enhancement, which causes the unnatural look and visual artifacts of the processed i...

  2. Contrast-enhanced MR angiography of cavopulmonary connections in adult patients with congenital heart disease.

    Science.gov (United States)

    Wagner, Moritz; Nguyen, Kim-Lien; Khan, Sarah; Mirsadraee, Saeed; Satou, Gary M; Aboulhosn, Jamil; Finn, J Paul

    2012-11-01

    The purpose of this study is to evaluate combined time-resolved and high-spatial resolution contrast-enhanced MR angiography (MRA) for assessment of cavopulmonary connections in adult patients with congenital heart disease. Twenty-eight adults with various surgical cavopulmonary connections (Glenn shunt and Fontan connection) underwent high-spatial-resolution contrast-enhanced MRA (voxel size, 1.95 mm(3); temporal resolution, 22 seconds) and time-resolved contrast-enhanced MRA (voxel size, 6.5-9.3 mm(3); temporal resolution, connections (using high-spatial-resolution contrast-enhanced MRA) and pulmonary artery (PA) perfusion patterns (using time-resolved contrast-enhanced MRA). High-spatial-resolution contrast-enhanced MRA yielded diagnostic-quality images for morphologic assessment of cavopulmonary connections in 27 of 28 (96%) patients. The anatomic dimensions (cross-sectional area) of the PA and cavopulmonary connections showed a wide variation (right PA, 0.99-5.67 cm(2); left PA, 0.80-5.69 cm(2); Glenn shunt, 0.93-6.94 cm(2); and Fontan connection, 1.25-6.67 cm(2)). The anatomic dimensions could be assessed with excellent interobserver agreement on high-spatial-resolution contrast-enhanced MRA (r = 0.895). Time-resolved contrast-enhanced MRA yielded diagnostic-quality images in all patients and enabled characterization of PA perfusion via the superior vena cava as follows: preferential inflow to the right PA (n = 12), preferential inflow to the left PA (n = 5), and balanced inflow to the right and left PA (n = 11). In those patients who had technically successful flow quantification measurements, phase contrast data confirmed patency of the cavopulmonary connections. Combined time-resolved contrast-enhanced MRA and high-spatial-resolution contrast-enhanced MRA allowed detailed morphologic and dynamic evaluation of cavopulmonary connections in adult patients with congenital heart disease. A wide variation in anatomic dimensions and perfusion patterns was

  3. Dynamic contrast-enhanced subtraction MR angiography in intracranial vascular abnormalities

    International Nuclear Information System (INIS)

    Takano, K.; Ono, H.; Utsunomiya, H.; Okazaki, M.; Tanaka, A.

    1999-01-01

    We present our clinical experience with dynamic contrast-enhanced MR angiography (MRA) with subtraction for assessing intracranial vascular abnormalities. Ten patients with various cerebrovascular disorders underwent dynamic contrast-enhanced MRA on a 1.0-T system. Thirty sections (2 mm) were acquired in 29-30 s. Maximum intensity projection images and subtracted source images were compared with those obtained by conventional angiography. In all cases, the presence or absence of abnormalities in the targeted vessels, as well as the morphology of the sagittal sinuses, was clearly visualized as in conventional angiography, without any obstructions such as hyperintense hematomas or thrombi, or intraluminal turbulence. Although the temporal and spatial resolutions with current hardware are insufficient, these preliminary results suggest that dynamic contrast-enhanced MRA with subtraction may be useful for assessing vascular lesions with hemorrhage or thrombus, and the dural sinuses. (orig.)

  4. Combination of contrast-enhanced wall motion analysis and myocardial deformation imaging during dobutamine stress echocardiography.

    Science.gov (United States)

    Nagy, Anikó I; Sahlén, Anders; Manouras, Aristomenis; Henareh, Loghman; da Silva, Cristina; Günyeli, Elif; Apor, Astrid A; Merkely, Béla; Winter, Reidar

    2015-01-01

    The combination of deformation analysis with conventional wall motion scoring (WMS) has been shown to increase the diagnostic sensitivity of dobutamine stress echocardiography (DSE). The feasibility and diagnostic power of WMS is largely improved by contrast agents; however, they are not used in combination with deformation analysis, as contrast agents are generally considered to render strain measurement unfeasible. To assess the feasibility of tissue velocity (TVI)- and 2D speckle tracking (ST)-based strain analysis during contrast-enhanced DSE; and to show whether there is an incremental value in combining deformation analysis with contrast-enhanced WMS. DS echocardiograms containing native, tissue Doppler, and contrast-enhanced loops of 60 patients were analysed retrospectively. The feasibility of WMS, TVI-, and ST-strain measurement was determined in 40 patients according to pre-defined criteria. The diagnostic ability of a combined protocol integrating data from contrast-WMS and TVI-strain measurement was then compared with contrast-WMS alone in all 60 patients, using coronary angiograms as a gold standard. Both TVI- and ST-based strain analysis were feasible during contrast-DSE (feasibility at peak stress: 87 and 75%). At the patient level, the diagnostic accuracy of the combined method did not prove superior to contrast-WMS (82 vs. 78%); a trend towards improved sensitivity and specificity for detecting coronary artery disease in the right coronary artery circulation (sensitivity: 85 vs. 77%, P = NS; specificity: 96 vs. 94%) was, however, observed. Both TVI- and ST-based myocardial deformation analysis are feasible during contrast-enhanced DSE, however, our results fail to demonstrate a clear diagnostic benefit of additional strain analysis over expert WMS alone. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  5. A contrast-enhanced ultrasound study of benign and malignant ...

    African Journals Online (AJOL)

    A contrast-enhanced ultrasound study of benign and malignant breast tissue. S Barnard, E Leen, T Cooke, W Angerson. Abstract. Objective. To determine the diagnostic value of haemodynamic contrast-enhanced ultrasound assessment in benign and malignant breast tissue, using histological examination as the reference ...

  6. High-dose contrast-enhanced MRI in multiple sclerosis

    International Nuclear Information System (INIS)

    Koudriavtseva, T.; Pozzilli, C.; Di Biasi, C.; Iannilli, M.; Trasimeni, G.; Gasperini, C.; Argentino, C.; Gualdi, G.F.

    1996-01-01

    Contrast-enhanced MRI is effective for assessing disease activity in multiple sclerosis (MS) and may provide an outcome measure for testing the efficacy of treatment in clinical trials. To compare the sensitivity of high-dose gadolinium-HP-DO3A with that of a standard dose of gadolinium-DTPA, we studied 16 patients with relapsing-remitting MS in the acute phase of the disease. Each underwent two MRI examinations within at most 48 h. The initial MRI study was with a standard dose of gadolinium-DTPA (0.1 mmol/kg), and the second one an experimental dose of gadolinium-HP-DO3A (0.3 mmol/kg). No adverse effects were attributed to the contrast media. The high-dose study revealed more enhancing lesions than the standard-dose study (56 vs 38). This difference was found to be more relevant for infratentorial and small lesions. Furthermore, with the higher dose, there was a marked qualitative improvement in the visibility and delineation of the lesions. (orig.). With 4 figs., 2 tabs

  7. Predicting Neck Abscess with Contrast-Enhanced Computed Tomography

    Directory of Open Access Journals (Sweden)

    Melisa Lim Seer Yee

    2014-01-01

    Full Text Available Neck abscesses are difficult to diagnose and treat. Currently, contrast-enhanced computed tomography (CECT is the imaging modality of choice. The study aims to determine the predictive value of CECT findings in diagnosing neck abscess, causes of neck abscess and the most common neck space involved in the local population. 84 consecutive patients clinically suspected to have neck abscess who underwent CECT and surgical confirmation of pus were included. Demographic and clinical data were recorded. 75 patients were diagnosed as having neck abscess on CECT; out of those 71 patients were found to have pus. Overall CECT findings were found to have a high sensitivity (98.6% and positive predictive value (PPV (94.7% but lower specificity (67.2% in diagnosing neck abscess. The CECT diagnostic criterion with the highest PPV is the presence of rim irregularity (96%. The most common deep neck space involved is the submandibular compartment, which correlates with the finding that odontogenic cause was the most common identifiable cause of abscess in the study population. Thus, in a patient clinically suspected of having neck abscess, CECT findings of a hypodense mass with rim irregularity are helpful in confirming the diagnosis and guiding clinical management.

  8. Enhancement pattern of hilar cholangiocarcinoma: Contrast-enhanced ultrasound versus contrast-enhanced computed tomography

    International Nuclear Information System (INIS)

    Xu Huixiong; Chen Lida; Xie Xiaoyan; Xie Xiaohua; Xu Zuofeng; Liu Guangjian; Lin Manxia; Wang Zhu; Lu Mingde

    2010-01-01

    Objective: To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT). Methods: Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated. Results: In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P = 0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P = 0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ultrasound, 89.5% (17/19) for CEUS, and 78.9% (15/19) for CECT (all P > 0.05 between every two groups). CEUS significantly improved the lesion conspicuity in comparison with CECT. CEUS and CECT made correct diagnoses in 30 (93.8%) and 25 (78.1%) lesions prior to pathological examination (P = 0.125). Conclusion: The enhancement pattern of hilar cholangiocarcinoma on CEUS was similar with that on CECT in arterial phase, whereas in portal phase hilar cholangiocarcinoma shows hypoenhancement more likely on CEUS. CEUS and CECT lead to similar results in evaluating portal vein infiltration and diagnosis of this entity.

  9. Usefulness of contrast enhanced cardiac computed tomography in myocardial infarction

    International Nuclear Information System (INIS)

    Morooka, Nobuhiro; Yamada, Zenju; Watanabe, Shigeru

    1982-01-01

    Contrast enhanced cardiac computed tomography (CECT) was performed in 33 patients with transmural myocardial infarction. The anterior wall thickness assessed by CECT was well correlated with that by left ventriculography in RAO projection. When the septal wall thickness was compared between ECG gated and non-gated CECT images, the septal wall thickness by non-gated CECT showed a close coincidence with the diastolic wall thickness by ECG gated CECT. In all patients, the thickness of the septal, anterior and postero-lateral walls was measured. The mean wall thickness in patients of antero-septal infarction was 9.0 +- 1.9 mm for the septal wall, 6.3 +- 1.3 mm for the anterior wall, and 10.0 +- 2.1 mm for the postero-lateral wall. In patients of infero-lateral infarction, the mean wall thickness was 12.2 +- 1.7 mm for the septal wall, 10.8 +- 1.6 mm for the anterior wall and 8.9 +- 1.2 mm for the postero-lateral wall. A filling defect was revealed in the infarcted area when CECT was performed in patients with acute myocardial infarction within 1 week from the onset, and late enhancement was demonstrated by plain CT performed 10 min later. Left ventricular aneurysms were noted in 16 of 23 patients of anteroseptal infarction, and 8 of these 16 had mural thrombi in the left ventricle. Coronary artery calcification was found in 11 of 33 myocardial infarction patients. In patients with aortocoronary bypass graft, the sequential scan (dynamic scan) was shown to be a useful non-invasive method because it showed whether the graft was patent or not. (J.P.N.)

  10. Post-operative monitoring of tissue transfers: advantages using contrast enhanced ultrasound (CEUS) and contrast enhanced MRI (ceMRI) with dynamic perfusion analysis?

    Science.gov (United States)

    Lamby, P; Prantl, L; Fellner, C; Geis, S; Jung, E M

    2011-01-01

    The immediate evaluation of microvascular tissue flaps with respect to microcirculation after transplantation is crucial for optimal monitoring and outcome. The purpose of our investigation was to evaluate the clinical value of contrast-enhanced ultrasound (CEUS) and contrast-enhanced MRI (ceMRI) for monitoring the integrity of tissue flaps in plastic surgery. To this end, we investigated 10 patients (47 ± 16 a) between postoperative day 7 and 14 who underwent flap surgery in order to cover tissue defects in various body regions. For CEUS we utilized the GE LOGIQ E9 equipped with a linear transducer (6-9 MHz). After application of 2.4 ml SonoVue, the tissue perfusion was detected in Low MI-Technique (MI present, both technologies provide an optimal assessment of perfusion in cutaneous, subcutaneous and muscle tissue layers, whereby the detection of fatty tissue perfusion is currently more easily detected using CEUS compared to ceMRI.

  11. FACTORES DE RIESGO CARDIOVASCULAR Y CALIDAD DE VIDA EN MUJERES REVASCULARIZADAS CON STENT CORONARIOS / Cardiovascular risk factors and quality of life in women who under-went revascularization with coronary stenting

    Directory of Open Access Journals (Sweden)

    José C. Castillo Núñez

    2013-10-01

    descriptive, longitudinal prospective study was conducted in women (n=62 who underwent revascularization with PTCA and stent implantation from January to June 2011. Clinical follow-up was performed for 180 days through medical consultations. Results: The mean age was 52.8 years and the most frequent cardiovascular risk factor was hypertension (66.1 %; diabetes (24.2 % was the least prevalent. One-vessel atherosclerotic coronary artery disease was the most common (87.1%, and three-vessel disease (1.6% was the least frequent one. Only one stent was implanted in 75.8 % of patients, and only one patient required the implantation of three stents; 83.9% of patients expressed that their quality of life was good, 14.5 % considered it was acceptable and one patient estimated it was poor. During clinical follow-up, no cardiovascular events was reported in 93.5 % of patients. Diabetes and poor quality of life showed a statistically significant association with the extent of atherosclerotic coronary artery disease, the number of stents used and cardiovascular events. Conclusions: Women with atherosclerotic coronary artery disease who underwent revascularization with coronary stents show a high frequency of risk factors, and have a favorable clinical course with a prevalence of positive perceptions concerning their quality of life.

  12. Usefulness of Multiple Biomarkers for Predicting Incident Major Adverse Cardiac Events in Patients Who Underwent Diagnostic Coronary Angiography (from the Catheter Sampled Blood Archive in Cardiovascular Diseases [CASABLANCA] Study).

    Science.gov (United States)

    McCarthy, Cian P; van Kimmenade, Roland R J; Gaggin, Hanna K; Simon, Mandy L; Ibrahim, Nasrien E; Gandhi, Parul; Kelly, Noreen; Motiwala, Shweta R; Belcher, Arianna M; Harisiades, Jamie; Magaret, Craig A; Rhyne, Rhonda F; Januzzi, James L

    2017-07-01

    We sought to develop a multiple biomarker approach for prediction of incident major adverse cardiac events (MACE; composite of cardiovascular death, myocardial infarction, and stroke) in patients referred for coronary angiography. In a 649-participant training cohort, predictors of MACE within 1 year were identified using least-angle regression; over 50 clinical variables and 109 biomarkers were analyzed. Predictive models were generated using least absolute shrinkage and selection operator with logistic regression. A score derived from the final model was developed and evaluated with a 278-patient validation set during a median of 3.6 years follow-up. The scoring system consisted of N-terminal pro B-type natriuretic peptide (NT-proBNP), kidney injury molecule-1, osteopontin, and tissue inhibitor of metalloproteinase-1; no clinical variables were retained in the predictive model. In the validation cohort, each biomarker improved model discrimination or calibration for MACE; the final model had an area under the curve (AUC) of 0.79 (p Time-to-first MACE was shorter in those with an elevated score (p <0.001); such risk extended to at least to 4 years. In conclusion, in a cohort of patients who underwent coronary angiography, we describe a novel multiple biomarker score for incident MACE within 1 year (NCT00842868). Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Low-Level Laser and Light-Emitting Diode Therapy for Pain Control in Hyperglycemic and Normoglycemic Patients Who Underwent Coronary Bypass Surgery with Internal Mammary Artery Grafts: A Randomized, Double-Blind Study with Follow-Up.

    Science.gov (United States)

    Lima, Andréa Conceição Gomes; Fernandes, Gilderlene Alves; Gonzaga, Isabel Clarisse; de Barros Araújo, Raimundo; de Oliveira, Rauirys Alencar; Nicolau, Renata Amadei

    2016-06-01

    This study aimed to evaluate the efficacy of low-level laser therapy (LLLT) and light-emitting diodes (LEDs) for reducing pain in hyperglycemic and normoglycemic patients who underwent coronary artery bypass surgery with internal mammary artery grafts. This study was conducted on 120 volunteers who underwent elective coronary artery bypass graft (CABG) surgery. The volunteers were randomly allocated to four different groups of equal size (n = 30): control, placebo, LLLT [λ = 640 nm and spatial average energy fluence (SAEF) = 1.06 J/cm(2)], and LED (λ = 660 ± 20 nm and SAEF = 0.24 J/cm(2)). Participants were also divided into hyperglycemic and normoglycemic subgroups, according to their fasting blood glucose test result before surgery. The outcome assessed was pain during coughing by a visual analog scale (VAS) and the McGill Pain Questionnaire. The patients were followed for 1 month after the surgery. The LLLT and LED groups showed a greater decrease in pain, with similar results, as indicated by both the VAS and the McGill questionnaire (p ≤ 0.05), on the 6th and 8th postoperative day compared with the placebo and control groups. The outcomes were also similar between hyperglycemic and normoglycemic patients. One month after the surgery, almost no individual reported pain during coughing. LLLT and LED had similar analgesic effects in hyperglycemic and normoglycemic patients, better than placebo and control groups.

  14. Prognostic Impact of Combined Dysglycemia and Hypoxic Liver Injury on Admission in Patients With ST-Segment Elevation Myocardial Infarction Who Underwent Primary Percutaneous Coronary Intervention (from the INTERSTELLAR Cohort).

    Science.gov (United States)

    Jang, Ho-Jun; Oh, Pyung Chun; Moon, Jeonggeun; Suh, Jon; Park, Hyun Woo; Park, Sang-Don; Lee, Kyounghoon; Kim, Je Sang; Lee, Hyun Jong; Choi, Rak Kyeong; Choi, Young-Jin; Kang, Woong Chol; Kwon, Sung Woo; Kim, Tae-Hoon

    2017-04-15

    Dysglycemia on admission is known to predict the prognosis of ST-segment elevation myocardial infarction (STEMI). Recently, hypoxic liver injury (HLI) has been proposed as a novel prognosticator for STEMI. We evaluated the prognostic impact of combined dysglycemia and HLI at the time of presentation in patients with STEMI who underwent primary percutaneous coronary intervention. From 2007 to 2014, 1,525 consecutive patients (79% men, mean age 61 years) who underwent primary percutaneous coronary intervention for STEMI in the INTERSTELLAR (Incheon-Bucheon Cohort of Patients Undergoing Primary PCI for Acute ST-Elevation Myocardial Infarction) cohort were analyzed retrospectively. Dysglycemia was defined as either hypoglycemia (serum glucose 250 mg/dl). HLI was defined as more than twofold increase of any serum aminotransferases above the upper normal limit. Patients were divided into 4 groups according to their dysglycemia and HLI status on admission: group 1, normoglycemia without HLI; group 2, dysglycemia without HLI; group 3, normoglycemia with HLI; and group 4, dysglycemia with HLI. Primary end point was inhospital death and secondary end point was all-cause mortality at 12 months after the index procedure. Of the 1,525 patients, there were 87 inhospital deaths (5.7%) and 113 all-cause deaths (7.4%) at 12 months after the index procedure. Both dysglycemia and HLI on admission were independent predictors of inhospital death. Inhospital mortality rate was the highest in group 4 (32.1%), followed by groups 2 and 3. Kaplan-Meier survival analysis at 12 months showed similar trends among the 4 groups. In conclusion, combined dysglycemia and HLI on admission predicts early prognosis for STEMI. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Contrast-enhanced MR angiography in Leriche's syndrome

    International Nuclear Information System (INIS)

    Link, J.; Steffens, J.C.; Brossmann, J.; Heller, M.; Loose, R.

    1998-01-01

    Purpose: To determine the usefulness of contrast-enhanced MR angiography for the diagnosis of Leriche's syndrome. Material and methods: Leriche's syndrome was seen in 7 patients via DSA. In [dition, contrast-enhanced MR angiography was performed (T R 7.8 ms/T E 2.1 ms, flip angle 30 , slab thickness 116 mm, slice thickness 1.82 mm, 64 partitions, FOV 500x438 mm, matrix 224x512). Results: Diagnosis of Leriche's syndrome was possible by contrast-enhanced MR angiography in each case. Visualisation of the femoral arteries was not possible in two patients by intraarterial DSA, in three other patients there was an insufficient contrast in the femoral arteries with DSA. Contrast-enhanced MR angiography revealed good visualisation of the femoral arteries in these patients. In [dition, contrast-enhanced MR angiography allowed complete visualisation of the patent lower limb arteries. In intraarterial DSA visualisation of the lower limb arteries was achieved reached in only one patient, but was incomplete. Conclusion: Contrast-enhanced MR angiography yielded the correct diagnosis of Leriche's syndrome in all 7 patients. Contrast-enhanced MR angiography was superior to DSA in the assessment of the distal run-off vessels in five of seven patients. (orig.) [de

  16. Multi-phasic CT versus dynamic contrast enhanced MRI in characterization of parotid gland tumors

    OpenAIRE

    Mohamed Metwally Abo El Atta; Talal Ahmed Amer; Ghada Mohamed Gaballa; Nehal Tharwat Mohammed El-Sayed

    2016-01-01

    Objective: Salivary gland tumors are challenging as regards preoperative diagnosis. The aim of our study was to highlight the value of multiphasic CT and contrast enhanced dynamic MRI in characterization of benign and malignant parotid tumors as well as to compare diagnostic accuracy of both modalities. Patients and methods: Study group included 45 patients (54 lesions), 26 males and 19 females, their age ranged from 24 to 78 years. All patients underwent both CT and MRI examinations. Time...

  17. Global Contrast Enhancement Based Image Forensics Using Statistical Features

    Directory of Open Access Journals (Sweden)

    Neetu Singh

    2017-01-01

    Full Text Available The evolution of modern cameras, mobile phones equipped with sophisticated image editing software has revolutionized digital imaging. In the process of image editing, contrast enhancement is a very common technique to hide visual traces of tampering. In our work, we have employed statistical distribution of block variance and AC DCT coefficients of an image to detect global contrast enhancement in an image. The variation in statistical parameters of block variance and AC DCT coefficients distribution for different degrees of contrast enhancement are used as features to detect contrast enhancement. An SVM classifier with 10-fold cross-validation is employed. An overall accuracy greater than 99% in detection with false rate less than 2% has been achieved. The proposed method is novel and it can be applied to uncompressed, previously JPEG compressed and post enhancement JPEG compressed images with high accuracy. The proposed method does not employ oft-repeated image histogram-based approach.

  18. Potential Cost Savings of Contrast-Enhanced Digital Mammography.

    Science.gov (United States)

    Patel, Bhavika K; Gray, Richard J; Pockaj, Barbara A

    2017-06-01

    The purpose of this article is to discuss whether the sensitivity and specificity of contrast-enhanced digital mammography (CEDM) render it a viable diagnostic alternative to breast MRI. That CEDM couples low-energy images (comparable to the diagnostic quality of standard mammography) and subtracted contrast-enhanced mammograms make it a cost-effective modality and a realistic substitute for the more costly breast MRI.

  19. Evaluation of delayed contrast-enhanced CT scan in diagnosing hilar cholangiocarcinoma

    International Nuclear Information System (INIS)

    Li Jianding; Liang Chenyang; Zhang Hua; Zhang Yuezhen; Li Rui

    2001-01-01

    Objective: To assess the diagnostic value of delayed CT contrast enhancement patterns in hilar cholangiocarcinoma based on two-phased dynamic incremental CT scanning. Methods: Fifty-two patients with suspected hilar tumor and bile duct obstruction underwent spiral CT scan. The scan time for one revolution of the X-ray tube was 1 second. To elucidate the delay time for optimal imaging, all proved cholangiocarcinoma with delayed (6, 8, 10, 15, 20, 30 minutes) post-equilibrium-phase contrast-enhanced CT scans were acquired with unenhanced, dynamic contrast-enhanced, and delayed images. Degree of delayed enhancement was compared with that of surrounding liver parenchyma. Results: (1) 8-15 minutes after IV injection of contrast material was the delay time for optimal imaging. (2) Of 29 cholangiocarcinomas, the early CT showed hypo-attenuating (lower than that of liver parenchyma) in 23 tumors, iso-attenuating (equal to that of the liver) in 4 tumors, and hyper-attenuating (higher than that of liver) in 2 tumors. The delayed CT scan showed iso-attenuating in 8 tumors, hyper-attenuating in 21 tumors, and no hypo-attenuating. Most of delay imaging of hilar cholangiocarcinoma may appear hyper-attenuating (U = -4.3073, P 2 = 9.09, P < 0.01). Conclusion: When assessing hilar tumor, delayed CT contrast enhancement patterns based on two-phase dynamic incremental CT scans is useful in the detection and characterization of hilar cholangiocarcinoma

  20. Polycystic ovary syndrome: dynamic contrast-enhanced ovary MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Erdem, C. Zuhal E-mail: sunarerdem@yahoo.com; Bayar, Ulku; Erdem, L. Oktay; Barut, Aykut; Gundogdu, Sadi; Kaya, Erdal

    2004-07-01

    Objective: to determine the enhancement behaviour of the ovaries in women with polycystic ovary syndrome (PCOS) by dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging and to compare these data with those of normal ovulating controls. Method: 24 women with PCOS and 12 controls underwent DCE-MR imaging. Dynamic images were acquired before and after injection of a contrast bolus at 30 s and the min of 1, 2, 3, 4 and 5. On postprocessing examination: (i) the ovarian volumes; (ii) the signal intensity value of each ovary per dynamic study; (iii) early-phase enhancement rate; (iv) time to peak enhancement (T{sub p}); and (v) percentage of washout of 5th min were determined. Data of the ovaries of the women with PCOS and controls were compared with Mann-Whitney U-test. Results: the mean values of T{sub p} were found to be significantly lower in women with PCOS than in controls (p<0.05). On the other hand, the mean values of ovarian volume, the early-phase enhancement rate, and percentage of washout of 5th min of ovaries were significantly higher in PCOS patients (p<0.05). Examination of the mean signal intensity-time curve revealed the ovaries in women with PCOS showed a faster and greater enhancement and wash-out. Conclusion: the enhancement behaviour of ovaries of women with PCOS may be significantly different from those of control subjects on DCE-MR imaging examination. In our experience, it is a valuable modality to highlight the vascularization changes in ovarian stroma with PCOS. We believe that improved DCE-MR imaging techniques may also provide us additional parameters in the diagnosis and treatment strategies of PCOS.

  1. Polycystic ovary syndrome: dynamic contrast-enhanced ovary MR imaging

    International Nuclear Information System (INIS)

    Erdem, C. Zuhal; Bayar, Ulku; Erdem, L. Oktay; Barut, Aykut; Gundogdu, Sadi; Kaya, Erdal

    2004-01-01

    Objective: to determine the enhancement behaviour of the ovaries in women with polycystic ovary syndrome (PCOS) by dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging and to compare these data with those of normal ovulating controls. Method: 24 women with PCOS and 12 controls underwent DCE-MR imaging. Dynamic images were acquired before and after injection of a contrast bolus at 30 s and the min of 1, 2, 3, 4 and 5. On postprocessing examination: (i) the ovarian volumes; (ii) the signal intensity value of each ovary per dynamic study; (iii) early-phase enhancement rate; (iv) time to peak enhancement (T p ); and (v) percentage of washout of 5th min were determined. Data of the ovaries of the women with PCOS and controls were compared with Mann-Whitney U-test. Results: the mean values of T p were found to be significantly lower in women with PCOS than in controls (p<0.05). On the other hand, the mean values of ovarian volume, the early-phase enhancement rate, and percentage of washout of 5th min of ovaries were significantly higher in PCOS patients (p<0.05). Examination of the mean signal intensity-time curve revealed the ovaries in women with PCOS showed a faster and greater enhancement and wash-out. Conclusion: the enhancement behaviour of ovaries of women with PCOS may be significantly different from those of control subjects on DCE-MR imaging examination. In our experience, it is a valuable modality to highlight the vascularization changes in ovarian stroma with PCOS. We believe that improved DCE-MR imaging techniques may also provide us additional parameters in the diagnosis and treatment strategies of PCOS

  2. Temporal subtraction contrast-enhanced dedicated breast CT

    Science.gov (United States)

    Gazi, Peymon M.; Aminololama-Shakeri, Shadi; Yang, Kai; Boone, John M.

    2016-09-01

    The development of a framework of deformable image registration and segmentation for the purpose of temporal subtraction contrast-enhanced breast CT is described. An iterative histogram-based two-means clustering method was used for the segmentation. Dedicated breast CT images were segmented into background (air), adipose, fibroglandular and skin components. Fibroglandular tissue was classified as either normal or contrast-enhanced then divided into tiers for the purpose of categorizing degrees of contrast enhancement. A variant of the Demons deformable registration algorithm, intensity difference adaptive Demons (IDAD), was developed to correct for the large deformation forces that stemmed from contrast enhancement. In this application, the accuracy of the proposed method was evaluated in both mathematically-simulated and physically-acquired phantom images. Clinical usage and accuracy of the temporal subtraction framework was demonstrated using contrast-enhanced breast CT datasets from five patients. Registration performance was quantified using normalized cross correlation (NCC), symmetric uncertainty coefficient, normalized mutual information (NMI), mean square error (MSE) and target registration error (TRE). The proposed method outperformed conventional affine and other Demons variations in contrast enhanced breast CT image registration. In simulation studies, IDAD exhibited improvement in MSE (0-16%), NCC (0-6%), NMI (0-13%) and TRE (0-34%) compared to the conventional Demons approaches, depending on the size and intensity of the enhancing lesion. As lesion size and contrast enhancement levels increased, so did the improvement. The drop in the correlation between the pre- and post-contrast images for the largest enhancement levels in phantom studies is less than 1.2% (150 Hounsfield units). Registration error, measured by TRE, shows only submillimeter mismatches between the concordant anatomical target points in all patient studies. The algorithm was

  3. A prospective study on the risk of contrast induced nephropathy in the patients who underwent contrast-enhanced CT examination

    International Nuclear Information System (INIS)

    Zhang Baocui; Zhang Yudong; Zhao Kai; Wang Xiaoying; Jiang Xuexiang

    2013-01-01

    Objective: To investigate the incidence of contrast induced nephropathy (CIN) among different patient groups after contrast agent injection. Methods: A total of 1243 patients were included in this study (male = 694, female = 549). The SCr level one week before and 72 hours after the CT examination and the incidence of CIN were recorded and comparison was made among groups according to sex, age, body mass index (BMI), the history of high blood pressure (HBP), diabetes mellitus (DM), chronic kidney disease (CKD), chronic heart failure (CHF), tumor, nephrotoxicity drug (NTD) usage. The frequency, type, dose and injection velocity of the contrast media (CM) were also recorded. Multivariate predictors of CIN were identified by Logistic regression using step-wise selection with entry and exit criteria of P < 0.10, results were tabulated as odds ratios (OR) with 95% confidence intervals (CI). Results: Among 1243 consecutive patients, the incidence of CIN was 5.5% (68/1243). Patients with a history of HBP, DM, CHF, CKD or tumor presented with higher incidence of CIN than that of controls (5.9%, 51/868 vs. 4.5%, 17/375). CIN developed in 9 of 203 patients (4.4%, 9/203) with CKD and in 59 of 1040 patients (5.7%, 59/1040) without CKD. There was no significant difference between the two groups (χ 2 = 0.51, P = 0.30). In CKD (-) group, the incidence of CIN was higher in females, patients with DM and patients using LOCM than those of males, DM (-) and using low osmolality contrast medium (IOCM) (P < 0.05), but there was no statistical significance in CKD (+) group. Logistic regression analysis showed that women, age ≥ 75 years, DM, LOCM, NTD, tumor, the time of using CM more than once per month were the most significant predictors of CIN (OR > 1). Conclusion: Women, age ≥ 75 years, LOCM, NTD, tumor, and the frequency of using CM more than once per month were more likely to develop CIN. (authors)

  4. Contrast-enhanced CISS imaging of cerebellopontine angle tumors

    Energy Technology Data Exchange (ETDEWEB)

    Tozaki, Mitsuhiro; Toyoda, Keiko; Hata, Yuichi; Fukuda, Yasushi; Fukuda, Kunihiko [Jikei Univ., Tokyo (Japan). School of Medicine; Katano, Shuichi

    1999-10-01

    Our purpose of this study was to evaluate the clinical usefulness of contrast-enhanced CISS-3DFT MR imaging for the diagnosis of CP angle tumors. CISS-3DFT MR imaging is expected for screening procedure of acoustic schwannoma because of excellent spatial resolution. Recently, we discovered contrast enhancement effect on CISS sequence in spite of heavily T{sub 2}-weighted images. Fourteen patients with CP angle tumors were performed on a 1.0 T MR unit. Transaxial CISS-3DFT MRI was obtained both before and after intravenous injections of Gd-DTPA. Multiplanar reconstructions (MPRs) were performed in all cases. Contrast enhancement effect of CP angle tumors, and the relationship between tumors and the adjacent cranial nerves were evaluated. Contrast enhancement effect of the tumors was present in all cases in spite of heavily T{sub 2}-weighted images of CISS sequences. In the internal auditory canal, relationship between the tumors and the cranial nerves was demonstrated in 6 cases (6/9). In the cerebellopontine cistern, all cases were demonstrated (11/11). Contrast-enhanced CISS-3DFT MR imaging with a good contrast resolution and an excellent spatial resolution is useful for the diagnosis of CP angle tumors. (author)

  5. CT contrast enhancement following renal cryoablation – artefact or treatment failure?

    DEFF Research Database (Denmark)

    Nielsen, Tommy Kjærgaard; Østraat, Øyvind; Andersen, Gratien

    (LCA) or percutaneous cryoablation (PCA) from August 2005 to August 2012 at Aarhus University Hospital. Six patients were excluded from analysis due to MRI follow-up. During routine postoperative CT follow-up, contrast enhancement of the cryolesion was identified in 34 of the 107 patients (32...... be carefully evaluated, as spontaneous resolution is commonly observed during postoperative follow-up. The importance of change in cryolesion size remains controversial and requires further research. If the PADUA score is ≥10 and attenuation levels exceed 39 HU on contrast enhancement CT, residual unablated...... the CT characteristics and treatment outcome of renal cryolesions demonstrating CE during postoperative follow-up. Material and methods: A retrospective review of Aarhus Cryoablation Register identified 113 patients with a pT1a biopsy verified malignant renal lesion who underwent primary laparoscopic...

  6. Contrast enhancement using histogram equalization based on logarithmic mapping

    Science.gov (United States)

    Kim, Wonkyun; You, Jongmin; Jeong, Jechang

    2012-06-01

    A widely used contrast enhancement method, the histogram equalization (HE) often produces images with unnatural appearances and visually disturbing artifacts because the HE compels the enhanced image to follow the uniform distribution. An adaptive histogram equalization using logarithmic mapping is presented, with a proposed algorithm based on a bin underflow and overflow method that achieves contrast enhancement by putting constraints on each histogram component differently. To incorporate characteristics of the human visual system, the logarithmic mapping function is used as constraint function, while the rate of contrast enhancement is controlled by determining the control parameters with the characteristics of the original image. The experimental results show that the proposed algorithm not only keeps the original histogram shape features, but also enhances the contrast effectively. Due to its simplicity, the proposed algorithm can be applied by simple hardware and processed in a real-time system.

  7. The relationship between contrast enhancement on CT and cerebral vasospasm in patient with subarachnoid hemorrhage

    International Nuclear Information System (INIS)

    Tazawa, Toshiaki; Mizukami, Masahiro; Kawase, Takeshi; Usami, Takashi; Togashi, Osamu

    1982-01-01

    Sixty patients with a single rupture of an aneurysm were subjected to study. Contrast enhanced CT (CECT) was performed by intravenous infusion of 100 ml of 60% meglumine iothalamate in 10 minutes. Post-contrast CT scans were repeated serially just after infusion, 15 minutes and 30 minutes later. Prominent increase in density in the region of the circle of Willis and its branches 30 minutes after infusion was considered as remarkable enhancement. In 17 (46%) out of 37 patients who underwent CECT within day 3, the contrast enhancement was remarkable. Transient or permanent symptomatic vasospasm occurred in 13 (76.5%) out of these 17 patients and the remaining 4 patients who underwent the operation with successful removal of subarachnoid clot within day 3 did not develop symptomatic vasospasm. Eight (67%) out of 12 patients operated within day 3, in whom post-operative CT showed incomplete removal of subarachnoid clot, developed transient or permanent symptomatic vasospasm. In only one (5%) out of 20 patients without remarkable enhancement, transient symptomatic vasospasm occurred. The abnormal contrast enhancement in the region of the circle of Willis and its branches within day 3 was closely related to the subsequent occurrence of vasospasm. Contrast enhanced CT was performed in 41 patients after day 3. There was no patient with remarkable enhancement on CECT. There was no relationship between the findings on CECT after day 3 and the occurrence of vasospasm. CECT within day 3 allows prediction of that patient destined for vasospasm and early removal of subarachnoid clot within day 3 may minimize the future development of vasospasm.(J.P.N.)

  8. Contrast-enhanced swallow study sensitivity for anastomotic leak detection in post-esophagectomy patients.

    Science.gov (United States)

    Mejía-Rivera, S; Pérez-Marroquín, S A; Cortés-González, R; Medina-Franco, H

    2018-03-07

    Esophagectomy is a highly invasive surgery and one of its postoperative complications is anastomotic leakage, occurring in 53% of cases. The aim of the present study was to determine the sensitivity of the contrast-enhanced swallow study as a method for diagnosing anastomotic leak in patients that underwent esophagectomy. The present retrospective study included the case records of patients that underwent esophagectomy with reconstruction and cervical anastomosis at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán within the time frame of January 1, 2000 and May 31, 2006. Demographic, clinical, and laboratory data emphasizing clinical and radiographic anastomotic leak detection were identified. Descriptive statistics were carried out and contrast-enhanced swallow study sensitivity for diagnosing leakage was calculated. Seventy patients were included in the analysis. The mean age of the patients was 50.6 years, 51 of the patients were men (72.86%), and 19 were women (27.14%). Indications for surgery were benign lesion in 29 patients (41.4%) and malignant lesion in 41 (58.6%). A total of 44.3% of the patients presented with a comorbidity, with diabetes mellitus and high blood pressure standing out. Thirty patients (42.85%) presented with anastomotic leak. Contrast-enhanced swallow study sensitivity for leak detection was 43.33%. The diagnostic sensitivity of the contrast-enhanced swallow study was very low. Therefore, we recommend the discontinuation of its routine use as a method for diagnosing anastomotic leaks. Copyright © 2018 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

  9. Contrast-enhanced MRA for investigation of cerebral arteriovenous malformations.

    Science.gov (United States)

    Suzuki, M; Matsui, O; Kobayashi, K; Ueda, F; Saitoh, C; Katagiri, A; Sanada, J; Tawara, M; Terayama, N; Kawashima, H; Kida, S; Yamashita, J

    2003-04-01

    We evaluated contrast-enhanced MRA (enhanced 3-D fast gradient-echo [efgre3d] with spectral inversion recovery) for identification of 15 intracranial arteriovenous malformations (AVMs) in 14 patients. Demonstration of the feeding arteries was classified as good for 16 examinations on maximum-intensity projections and multiprojection volume reconstruction images. The nidus was seen well in all patients. Definition of the draining veins was good or fair except for one poor result. Therapeutic effects were clearly demonstrated in three follow-up series. Contrast-enhanced MRA using efgre3d is useful for delineation of AVMs and for follow-up after treatment.

  10. Contrast-enhanced MRA for investigation of cerebral arteriovenous malformations

    International Nuclear Information System (INIS)

    Suzuki, M.; Matsui, O.; Ueda, F.; Saitoh, C.; Katagiri, A.; Sanada, J.; Tawara, M.; Terayama, N.; Kawashima, H.; Kobayashi, K.; Kida, S.; Yamashita, J.

    2003-01-01

    We evaluated contrast-enhanced MRA (enhanced 3-D fast gradient-echo [efgre3d] with spectral inversion recovery) for identification of 15 intracranial arteriovenous malformations (AVMs) in 14 patients. Demonstration of the feeding arteries was classified as good for 16 examinations on maximum-intensity projections and multiprojection volume reconstruction images. The nidus was seen well in all patients. Definition of the draining veins was good or fair except for one poor result. Therapeutic effects were clearly demonstrated in three follow-up series. Contrast-enhanced MRA using efgre3d is useful for delineation of AVMs and for follow-up after treatment. (orig.)

  11. Three-dimensional black-blood contrast-enhanced MRI improves detection of intraluminal thrombi in patients with acute ischaemic stroke.

    Science.gov (United States)

    Jang, Won; Kwak, Hyo Sung; Chung, Gyung Ho; Hwang, Seung Bae

    2018-03-19

    This study evaluated the utility of three-dimensional (3D), black-blood (BB), contrast-enhanced, magnetic resonance imaging (MRI) for the detection of intraluminal thrombi in acute stroke patients. Forty-seven patients with acute stroke involving the anterior circulation underwent MRI examination within 6 h of clinical onset. Cerebral angiography was used as the reference standard. In a blinded manner, two neuroradiologists interpreted the following three data sets: (1) diffusion-weighted imaging (DWI) + 3D BB contrast-enhanced MRI; (2) DWI + susceptibility weighted imaging (SWI); (3) DWI + 3D BB contrast-enhanced MRI + SWI. Of these patients, 47 had clots in the middle cerebral artery and four had clots in the anterior cerebral artery. For both observers, the area under the curve (Az) for data sets 1 and 3, which included 3D BB contrast-enhanced MRI, was significantly greater than it was for data set 2, which did not include 3D BB contrast-enhanced MR imaging (observer 1, 0.988 vs 0.904, p = 0.001; observer 2, 0.988 vs 0.894, p = 0.000). Three-dimensional BB contrast-enhanced MRI improves detection of intraluminal thrombi compared to conventional MRI methods in patients with acute ischaemic stroke. • BB contrast-enhanced MRI helps clinicians to assess the intraluminal clot • BB contrast-enhanced MRI improves detection of intraluminal thrombi • BB contrast-enhanced MRI for clot detection has a higher sensitivity.

  12. Small-bowel MRI in children and young adults with Crohn disease: retrospective head-to-head comparison of contrast-enhanced and diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Neubauer, Henning; Evangelista, Laura; Wirth, Clemens; Beer, Meinrad; Pabst, Thomas; Machann, Wolfram; Koestler, Herbert; Hahn, Dietbert; Dick, Anke

    2013-01-01

    Small-bowel MRI based on contrast-enhanced T1-weighted sequences has been challenged by diffusion-weighted imaging (DWI) for detection of inflammatory bowel lesions and complications in patients with Crohn disease. To evaluate free-breathing DWI, as compared to contrast-enhanced MRI, in children, adolescents and young adults with Crohn disease. This retrospective study included 33 children and young adults with Crohn disease ages 17 ± 3 years (mean ± standard deviation) and 27 matched controls who underwent small-bowel MRI with contrast-enhanced T1-weighted sequences and DWI at 1.5 T. The detectability of Crohn manifestations was determined. Concurrent colonoscopy as reference was available in two-thirds of the children with Crohn disease. DWI and contrast-enhanced MRI correctly identified 32 and 31 patients, respectively. All 22 small-bowel lesions and all Crohn complications were detected. False-positive findings (two on DWI, one on contrast-enhanced MRI), compared to colonoscopy, were a result of large-bowel lumen collapse. Inflammatory wall thickening was comparable on DWI and contrast-enhanced MRI. DWI was superior to contrast-enhanced MRI for detection of lesions in 27% of the assessed bowel segments and equal to contrast-enhanced MRI in 71% of segments. DWI facilitates fast, accurate and comprehensive workup in Crohn disease without the need for intravenous administration of contrast medium. Contrast-enhanced MRI is superior in terms of spatial resolution and multiplanar acquisition. (orig.)

  13. Assessment of the link between quantitative biexponential diffusion-weighted imaging and contrast-enhanced MRI in the liver

    NARCIS (Netherlands)

    Dijkstra, Hildebrand; Oudkerk, Matthijs; Kappert, Peter; Sijens, Paul E.

    Purpose: To investigate if intravoxel incoherent motion (IVIM) modeled diffusion-weighted imaging (DWI) can be linked to contrast-enhanced (CE-)MRI in liver parenchyma and liver lesions. Methods: Twenty-five patients underwent IVIM-DWI followed by multiphase CE-MRI using Gd-EOB-DTPA (n = 20) or

  14. A Novel Contrast Enhancement Technique on Palm Bone Images

    Directory of Open Access Journals (Sweden)

    Yung-Tsang Chang

    2014-09-01

    Full Text Available Contrast enhancement plays a fundamental role in image processing. Many histogram-based techniques are widely used for contrast enhancement of given images, due to their simple function and effectiveness. However, the conventional histogram equalization (HE methods result in excessive contrast enhancement, which causes natural looking and satisfactory results for a variety of low contrast images. To solve such problems, a novel multi-histogram equalization technique is proposed to enhance the contrast of the palm bone X-ray radiographs in this paper. For images, the mean-variance analysis method is employed to partition the histogram of the original grey scale image into multiple sub-histograms. These histograms are independently equalized. By using this mean-variance partition method, a proposed multi-histogram equalization technique is employed to achieve the contrast enhancement of the palm bone X-ray radiographs. Experimental results show that the multi-histogram equalization technique achieves a lower average absolute mean brightness error (AMBE value. The multi-histogram equalization technique simultaneously preserved the mean brightness and enhanced the local contrast of the original image.

  15. Novel contrast-enhanced ultrasound imaging in prostate cancer

    NARCIS (Netherlands)

    Smeenge, Martijn; Mischi, Massimo; Laguna Pes, M. Pilar; de La Rosette, Jean J. M. C. H.; Wijkstra, Hessel

    2011-01-01

    The purposes of this paper were to present the current status of contrast-enhanced transrectal ultrasound imaging and to discuss the latest achievements and techniques now under preclinical testing. Although grayscale transrectal ultrasound is the standard method for prostate imaging, it lacks

  16. Contrast-enhanced ultrasound: clinical applications in patients with atherosclerosis

    NARCIS (Netherlands)

    A.F.L. Schinkel (Arend); M. Kaspar (Mathias); D. Staub (Daniel)

    2016-01-01

    textabstractContrast-enhanced ultrasound (CEUS) is increasingly being used to evaluate patients with known or suspected atherosclerosis. The administration of a microbubble contrast agent in conjunction with ultrasound results in an improved image quality and provides information that cannot be

  17. Contrast enhancement of the irradiated spinal cord in children

    International Nuclear Information System (INIS)

    Pettersson, H.; Harwood-Nash, D.C.; Fitz, C.R.; Chuang, S.; Armstrong, E.

    1981-01-01

    Four children are reported in whom marked contrast enhancement of the spinal cord and roots was demonstrated by computed tomography months to years after relatively low dose therapeutic irradiation of paraspinal tumors, the radiation field including the cord. This phenomenon, previously unreported, probably represents subclinical radiation injury. None of the children had any neurologic abnormalities

  18. Staging accuracy of pancreatic cancer: Comparison between non-contrast-enhanced and contrast-enhanced PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Yoneyama, Tomohiro [Department of Radiology, Yokohama City University, Graduate School of Medicine, Yokohama (Japan); Tateishi, Ukihide, E-mail: utateish@yokohama-cu.ac.jp [Department of Radiology, Yokohama City University, Graduate School of Medicine, Yokohama (Japan); Endo, Itaru [Department of Surgery, Yokohama City University, Graduate School of Medicine, Yokohama (Japan); Inoue, Tomio [Department of Radiology, Yokohama City University, Graduate School of Medicine, Yokohama (Japan)

    2014-10-15

    Purpose: Our aim was to clarify the diagnostic impact of contrast-enhanced (CE) {sup 18}F-fluorodeoxyglucose (FDG)–positron emission tomography (PET)/computed tomography (CT) for staging of pancreatic cancer compared to non-CE PET/CT. Method and materials: Between April 2006 and November 2009, a total of 95 patients (age range, 36–83 years [mean age, 67]) with primary pancreatic cancer underwent {sup 18}F-FDG PET/CT examinations. Diagnostic accuracy was compared between non-CE PET/CT and CE PET/CT. Images were analyzed visually and quantitatively by two blinded reviewers. Reference standard was histological examination in 48 patients (51%) and/or confirmation of an obvious progression in number and/or size of the lesions on follow-up CT examinations in 47 patients (49%). Results: For T-staging, invasion of duodenum (n = 20, 21%), mesentery (n = 12, 13%), and retroperitoneum (n = 13, 14%) was correctly diagnosed by both modalities. The ROC analyses revealed that the Az values of celiac artery (CA), common hepatic artery (CHA), splenic artery (SV), and superior mesenteric vein (SMV) invasion were significantly higher in the CE PET/CT group for both readers. Nodal metastasis was correctly diagnosed by CE PET/CT in 38 patients (88%) and by non-CE PET/CT in 45 patients (87%). Diagnostic accuracies of nodal metastasis in two modalities were similar. Using CE PET/CT, distant metastasis, scalene node metastasis, and peritoneal dissemination were correctly assigned in 39 patients (91%), while interpretation based on non-CE PET/CT revealed distant metastasis, scalene node metastasis, and peritoneal dissemination in 42 patients (81%). Diagnostic accuracy of distant metastasis, scalene node metastasis, and peritoneal dissemination with CE PET/CT was significantly higher than that of non-CE PET/CT (p < 0.05). Conclusion: CE PET/CT allows a more precise assessment of distant metastasis, scalene node metastasis, and peritoneal dissemination in patients with pancreatic cancer.

  19. Complex cystic renal masses: characterization with contrast-enhanced US.

    Science.gov (United States)

    Ascenti, Giorgio; Mazziotti, Silvio; Zimbaro, Giovanni; Settineri, Nicola; Magno, Carlo; Melloni, Darwin; Caruso, Rosario; Scribano, Emanuele

    2007-04-01

    To prospectively compare contrast material-enhanced ultrasonography (US) with computed tomography (CT) in the classification of complex cystic renal masses with the Bosniak system. Ethics committee approval and written informed consent were obtained. Forty patients (17 women, 23 men; age range, 31-77 years) with 44 complex cystic renal masses detected with conventional US were prospectively examined by using second-harmonic US with a second-generation contrast agent and multiphasic helical CT. Thirty-six patients had one lesion, and four patients had two lesions. Surgical resection in nine patients and imaging follow-up in 31 patients were used to determine the outcome. On contrast-enhanced US images, masses were classified as Bosniak category II (n = 18), IIF (ie, lesions were classified as category II and follow-up was needed) (n = 16), III (n = 7), or IV (n = 3) lesions. On CT images, masses were classified as Bosniak category II (n = 24), IIF (n = 10), III (n = 7), or IV (n = 3) lesions. Interobserver agreement was high (kappa = 0.86, P < .001) for classification with US. Complete concordance between the readers was found for classification with CT. Complete concordance between contrast-enhanced US and CT was observed in the differentiation of surgical and nonsurgical complex cysts. Complete concordance among the three readers in the assessment of vascularity with contrast-enhanced US was found. Interobserver agreement in the evaluation of enhancement on CT images was high (kappa = 0.88, P < .001). Concordance between contrast-enhanced US and CT in the evaluation of vascularization was high (kappa = 0.77, P < .001). The study data suggest that contrast-enhanced second-harmonic US is appropriate for renal cyst classification with the Bosniak system.

  20. Combined respiratory and cardiac triggering improves blood pool contrast-enhanced pediatric cardiovascular MRI

    International Nuclear Information System (INIS)

    Vasanawala, Shreyas S.; Newman, Beverley; Chan, Frandics P.; Alley, Marcus T.

    2011-01-01

    Contrast-enhanced cardiac MRA suffers from cardiac motion artifacts and often requires a breath-hold. This work develops and evaluates a blood pool contrast-enhanced combined respiratory- and ECG-triggered MRA method. An SPGR sequence was modified to enable combined cardiac and respiratory triggering on a 1.5-T scanner. Twenty-three consecutive children referred for pediatric heart disease receiving gadofosveset were recruited in HIPAA-compliant fashion with IRB approval and informed consent. Children underwent standard non-triggered contrast-enhanced MRA with or without suspended respiration. Additionally, a free-breathing-triggered MRA was acquired. Triggered and non-triggered studies were presented in blinded random order independently to two radiologists twice. Anatomical structure delineation was graded for each triggered and non-triggered acquisition and the visual quality on triggered MRA was compared directly to that on non-triggered MRA. Triggered images received higher scores from each radiologist for all anatomical structures on each of the two reading sessions (Wilcoxon rank sum test, P < 0.05). In direct comparison, triggered images were preferred over non-triggered images for delineating cardiac structures, with most comparisons reaching statistical significance (binomial test, P < 0.05). Combined cardiac and respiratory triggering, enabled by a blood pool contrast agent, improves delineation of most anatomical structures in pediatric cardiovascular MRA. (orig.)

  1. Contrast-enhanced ultrasonography for the determination of Crohn’s disease activity – preliminary experience

    Science.gov (United States)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Summary Background Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn’s disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Material/Methods Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Results Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. Conclusions CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn’s disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI. PMID:24723988

  2. Contrast-enhanced ultrasonography for the determination of Crohn's disease activity - preliminary experience.

    Science.gov (United States)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn's disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn's disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI.

  3. Contrast-enhanced ultrasonography for the determination of Crohn’s disease activity – preliminary experience

    International Nuclear Information System (INIS)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn’s disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn’s disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI

  4. Hypovolemic shock complex: does the pancreatic perfusion increase or decrease at contrast-enhanced dynamic CT?

    Science.gov (United States)

    Higashi, Hiroki; Tamada, Tsutomu; Kanki, Akihiko; Yamamoto, Akira; Ito, Katsuyoshi

    2014-01-01

    The purpose of this study is to evaluate contrast enhancement effects of the pancreas at dynamic computed tomography (CT) to clarify whether pancreatic perfusion increases or decreases in severe trauma patients with hypovolemic shock. A total of 90 patients with (n=30) and without (n=60) blunt trauma and hypovolemic shock who underwent dynamic CT for abdomen was included. The measurement of CT attenuation values of the pancreas in the early phase and the late phase was performed to compare the contrast enhancement effects between patients with and without hypovolemic shock. The mean CT attenuation values of the pancreas in the early phase of dynamic CT in patients with hypovolemic shock [95.4±29.1 Hounsfield units (HU)] were significantly lower (P perfusion in patients with hypovolemic shock. The mean CT attenuation values of the pancreas in the late phase of dynamic CT in patients with hypovolemic shock (95.9±17.6 HU) were significantly higher (P perfusion in the early phase and delayed pancreatic enhancement in the late phase of contrast-enhanced dynamic CT was a common finding in patients with hypovolemic shock. © 2014.

  5. Glioblastoma Presenting with Steroid-Induced Pseudoregression of Contrast Enhancement on Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Marcus D. Mazur

    2012-01-01

    Full Text Available Corticosteroid-induced reduction in contrast enhancement on radiographic imaging is most commonly associated with lymphoma but has been reported in other entities, including glioma. This finding may represent a diagnostic dilemma. Concern that steroid-induced cytotoxicity obscures histological diagnosis of suspected lymphoma may lead to postponement of a biopsy. If glioma is not considered in the differential diagnosis, reduction in tumor contrast enhancement may be misinterpreted as disease regression rather than a transient radiographic change. We report a case of a patient with an enhancing right temporoparietal mass adjacent to the atrium of the lateral ventricle. After treatment with dexamethasone was started, the mass exhibited marked reduction in contrast enhancement, with symptom improvement. The clinical course suggested lymphoma, and surgery was not performed. Subsequent screening for extra-axial lymphoma was negative. Two weeks later, the patient developed worsening symptoms, and repeat T1-weighted imaging showed interval increase in size and enhancement. The findings suggested a possible diagnosis of malignant glioma. The patient underwent a stereotactic-guided craniotomy for excision of the right temporoparietal mass lesion. Final histological diagnosis was glioblastoma multiforme, World Health Organization grade IV.

  6. Comparison of contrast-enhanced ultrasound and contrast-enhanced computed tomography in evaluating the treatment response to transcatheter arterial chemoembolization of hepatocellular carcinoma using modified RECIST

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ming; Lin, Man-xia; Xu, Zuo-feng; Wang, Wei; Xie, Xiao-yan [Sun Yat-Sen University, Department of Medical Ultrasonics, Guangzhou (China); Sun Yat-Sen University, The First Affiliated Hospital, Institute of Diagnostic and Interventional Ultrasound, Guangzhou (China); Lu, Ming-de; Kuang, Ming [Sun Yat-Sen University, Department of Hepatobiliary Surgery, Guangzhou (China); Sun Yat-Sen University, The First Affiliated Hospital, Institute of Diagnostic and Interventional Ultrasound, Guangzhou (China); Zheng, Ke-guo [Sun Yat-Sen University, Department of Radiology, Guangzhou (China); Zhuang, Wen-quan [Sun Yat-Sen University, Department of Interventional Radiology, Guangzhou (China)

    2015-08-15

    We aimed to compare contrast-enhanced ultrasound (CEUS) with contrast-enhanced computed tomography (CECT) for evaluating the treatment response to transcatheter arterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). Treatment responses of 130 patients who underwent TACE were evaluated by CEUS and CECT. We initially compared the abilities of CEUS and CECT to detect residual tumour, which were confirmed by histology or angiography. Then, we compared the tumour response to TACE assessed by CEUS and CECT, according to Modified Response Evaluation Criteria in Solid Tumours (mRECIST). The sensitivity and accuracy of detecting residual tumour by CEUS vs. CECT were 95.9 % vs. 76.2 % (p < 0.001) and 96.2 % vs. 77.7 % (p < 0.001), respectively. For target lesions, 13 patients were observed as complete response (CR) by CEUS, compared to 36 by CECT (p < 0.001). For nontarget lesions, 12 patients were observed as CR by CEUS, compared to 22 by CECT (p = 0.006). For overall response, eight patients were observed as CR by CEUS, compared to 31 by CECT (p < 0.001). The diagnostic performance of CEUS was superior to CECT for detecting residual tumour after TACE. In clinical, CEUS should be recommended as an optional procedure for assessing the tumour response to TACE. (orig.)

  7. Contrast enhancement of portal images by selective histogram equalization.

    Science.gov (United States)

    Crooks, I; Fallone, B G

    1993-01-01

    Because of the high energy of the treatment beam, contrast of portal verification films is very poor. A simple contrast enhancement technique is described which we have labeled selective histogram equalization (SHE), to improve visualization of double-exposure portal images and this facilitate the beam verification process. The technique performs separate histogram equalization on the treatment- and open-field sections of double-exposure portal images. Delineation of the treatment field edge and separation into two regions is performed automatically for off-line portal radiographs by a strategic combination of Sobel filtration and morphological processes. Analyses of images processed by SHE and other adaptive histogram equalization techniques indicate that SHE produces improved contrast enhancement with minimal addition of noise or artifacts, thus simplifying the beam verification procedure. The simple implementation of an automatic SHE process with on-line portal systems is also discussed.

  8. Adaptive image contrast enhancement using generalizations of histogram equalization.

    Science.gov (United States)

    Stark, J A

    2000-01-01

    This paper proposes a scheme for adaptive image-contrast enhancement based on a generalization of histogram equalization (HE). HE is a useful technique for improving image contrast, but its effect is too severe for many purposes. However, dramatically different results can be obtained with relatively minor modifications. A concise description of adaptive HE is set out, and this framework is used in a discussion of past suggestions for variations on HE. A key feature of this formalism is a "cumulation function," which is used to generate a grey level mapping from the local histogram. By choosing alternative forms of cumulation function one can achieve a wide variety of effects. A specific form is proposed. Through the variation of one or two parameters, the resulting process can produce a range of degrees of contrast enhancement, at one extreme leaving the image unchanged, at another yielding full adaptive equalization.

  9. Contrast enhanced ultrasound in the assessment of urogenital pathology

    Directory of Open Access Journals (Sweden)

    Libero Barozzi

    2014-12-01

    Full Text Available Contrast enhanced ultrasound (CEUS is an innovative technique that employs microbubble contrast agents to demonstrate parenchymal perfusion. Although initial clinical application was focused on the liver pathology, a wide variety of clinical conditions can be assessed now with CEUS. CEUS is a well-tolerated technique and is acquiring an increasing role in the assessment of renal pathology because contrast agents are not excreted by the kidney and do not affect the renal function. CEUS demonstrated an accuracy similar to contrast enhanced multi-detector computed tomography (CEMDCT in detecting focal lesions, with the advantage of the real-time assessment of microvascular perfusion by using time-intensity curves. The aim of this paper is to review the main indications of CEUS in the assessment of renal and urogenital pathology. Imaging examples are presented and described. Advantages and limitations of CEUS with reference to conventional US and CE-MDCT are discussed.

  10. Color and Contrast Enhancement by Controlled Piecewise Affine Histogram Equalization

    Directory of Open Access Journals (Sweden)

    Jose-Luis Lisani

    2012-10-01

    Full Text Available This paper presents a simple contrast enhancement algorithm based on histogram equalization (HE. The proposed algorithm performs a piecewise affine transform of the intensity levels of a digital image such that the new cumulative distribution function will be approximately uniform (as with HE, but where the stretching of the range is locally controlled to avoid brutal noise enhancement. We call this algorithm Piecewise Affine Equalization (PAE. Several experiments show that, in general, the new algorithm improves HE results.

  11. Contrast enhancement of the gyri in herpes simplex encephalitis

    International Nuclear Information System (INIS)

    Schumacher, K.A.; Langer, M.; Langer, R.

    1982-01-01

    A case of herpes simplex encephalitis was examined by computer tomography. Both cerebral hemispheres showed contrast enhancement of the gyri. The cause of this is considered. The increased contrast medium accumulation in the affected areas is probably due to the marked vascular proliferation which can be demonstrated anatomically, and to the rapid escape of contrast from the capillaries into the interstitial spaces. The findings of other authors, which differ somewhat, are discussed. (orig.) [de

  12. Algorithms for contrast enhancement of electronic portal images

    International Nuclear Information System (INIS)

    Díez, S.; Sánchez, S.

    2015-01-01

    An implementation of two new automatized image processing algorithms for contrast enhancement of portal images is presented as suitable tools which facilitate the setup verification and visualization of patients during radiotherapy treatments. In the first algorithm, called Automatic Segmentation and Histogram Stretching (ASHS), the portal image is automatically segmented in two sub-images delimited by the conformed treatment beam: one image consisting of the imaged patient obtained directly from the radiation treatment field, and the second one is composed of the imaged patient outside it. By segmenting the original image, a histogram stretching can be independently performed and improved in both regions. The second algorithm involves a two-step process. In the first step, a Normalization to Local Mean (NLM), an inverse restoration filter is applied by dividing pixel by pixel a portal image by its blurred version. In the second step, named Lineally Combined Local Histogram Equalization (LCLHE), the contrast of the original image is strongly improved by a Local Contrast Enhancement (LCE) algorithm, revealing the anatomical structures of patients. The output image is lineally combined with a portal image of the patient. Finally the output images of the previous algorithms (NLM and LCLHE) are lineally combined, once again, in order to obtain a contrast enhanced image. These two algorithms have been tested on several portal images with great results. - Highlights: • Two Algorithms are implemented to improve the contrast of Electronic Portal Images. • The multi-leaf and conformed beam are automatically segmented into Portal Images. • Hidden anatomical and bony structures in portal images are revealed. • The task related to the patient setup verification is facilitated by the contrast enhancement then achieved.

  13. Visual Contrast Enhancement Algorithm Based on Histogram Equalization.

    Science.gov (United States)

    Ting, Chih-Chung; Wu, Bing-Fei; Chung, Meng-Liang; Chiu, Chung-Cheng; Wu, Ya-Ching

    2015-07-13

    Image enhancement techniques primarily improve the contrast of an image to lend it a better appearance. One of the popular enhancement methods is histogram equalization (HE) because of its simplicity and effectiveness. However, it is rarely applied to consumer electronics products because it can cause excessive contrast enhancement and feature loss problems. These problems make the images processed by HE look unnatural and introduce unwanted artifacts in them. In this study, a visual contrast enhancement algorithm (VCEA) based on HE is proposed. VCEA considers the requirements of the human visual perception in order to address the drawbacks of HE. It effectively solves the excessive contrast enhancement problem by adjusting the spaces between two adjacent gray values of the HE histogram. In addition, VCEA reduces the effects of the feature loss problem by using the obtained spaces. Furthermore, VCEA enhances the detailed textures of an image to generate an enhanced image with better visual quality. Experimental results show that images obtained by applying VCEA have higher contrast and are more suited to human visual perception than those processed by HE and other HE-based methods.

  14. Algorithms for contrast enhancement of electronic portal images

    Science.gov (United States)

    Díez, S.; Sánchez, S.

    2015-11-01

    An implementation of two new automatized image processing algorithms for contrast enhancement of portal images is presented as suitable tools which facilitate the setup verification and visualization of patients during radiotherapy treatments. In the first algorithm, called Automatic Segmentation and Histogram Stretching (ASHS), the portal image is automatically segmented in two sub-images delimited by the conformed treatment beam: one image consisting of the imaged patient obtained directly from the radiation treatment field, and the second one is composed of the imaged patient outside it. By segmenting the original image, a histogram stretching can be independently performed and improved in both regions. The second algorithm involves a two-step process. In the first step, a Normalization to Local Mean (NLM), an inverse restoration filter is applied by dividing pixel by pixel a portal image by its blurred version. In the second step, named Lineally Combined Local Histogram Equalization (LCLHE), the contrast of the original image is strongly improved by a Local Contrast Enhancement (LCE) algorithm, revealing the anatomical structures of patients. The output image is lineally combined with a portal image of the patient. Finally the output images of the previous algorithms (NLM and LCLHE) are lineally combined, once again, in order to obtain a contrast enhanced image. These two algorithms have been tested on several portal images with great results.

  15. Contrast enhancement via texture region based histogram equalization

    Science.gov (United States)

    Singh, Kuldeep; Vishwakarma, Dinesh K.; Singh Walia, Gurjit; Kapoor, Rajiv

    2016-08-01

    This paper presents two novel contrast enhancement approaches using texture regions-based histogram equalization (HE). In HE-based contrast enhancement methods, the enhanced image often contains undesirable artefacts because an excessive number of pixels in the non-textured areas heavily bias the histogram. The novel idea presented in this paper is to suppress the impact of pixels in non-textured areas and to exploit texture features for the computation of histogram in the process of HE. The first algorithm named as Dominant Orientation-based Texture Histogram Equalization (DOTHE), constructs the histogram of the image using only those image patches having dominant orientation. DOTHE categories image patches into smooth, dominant or non-dominant orientation patches by using the image variance and singular value decomposition algorithm and utilizes only dominant orientation patches in the process of HE. The second method termed as Edge-based Texture Histogram Equalization, calculates significant edges in the image and constructs the histogram using the grey levels present in the neighbourhood of edges. The cumulative density function of the histogram formed from texture features is mapped on the entire dynamic range of the input image to produce the contrast-enhanced image. Subjective as well as objective performance assessment of proposed methods is conducted and compared with other existing HE methods. The performance assessment in terms of visual quality, contrast improvement index, entropy and measure of enhancement reveals that the proposed methods outperform the existing HE methods.

  16. Contrast Enhancement Algorithm Based on Gap Adjustment for Histogram Equalization

    Directory of Open Access Journals (Sweden)

    Chung-Cheng Chiu

    2016-06-01

    Full Text Available Image enhancement methods have been widely used to improve the visual effects of images. Owing to its simplicity and effectiveness histogram equalization (HE is one of the methods used for enhancing image contrast. However, HE may result in over-enhancement and feature loss problems that lead to unnatural look and loss of details in the processed images. Researchers have proposed various HE-based methods to solve the over-enhancement problem; however, they have largely ignored the feature loss problem. Therefore, a contrast enhancement algorithm based on gap adjustment for histogram equalization (CegaHE is proposed. It refers to a visual contrast enhancement algorithm based on histogram equalization (VCEA, which generates visually pleasing enhanced images, and improves the enhancement effects of VCEA. CegaHE adjusts the gaps between two gray values based on the adjustment equation, which takes the properties of human visual perception into consideration, to solve the over-enhancement problem. Besides, it also alleviates the feature loss problem and further enhances the textures in the dark regions of the images to improve the quality of the processed images for human visual perception. Experimental results demonstrate that CegaHE is a reliable method for contrast enhancement and that it significantly outperforms VCEA and other methods.

  17. Contrast Enhancement Algorithm Based on Gap Adjustment for Histogram Equalization.

    Science.gov (United States)

    Chiu, Chung-Cheng; Ting, Chih-Chung

    2016-06-22

    Image enhancement methods have been widely used to improve the visual effects of images. Owing to its simplicity and effectiveness histogram equalization (HE) is one of the methods used for enhancing image contrast. However, HE may result in over-enhancement and feature loss problems that lead to unnatural look and loss of details in the processed images. Researchers have proposed various HE-based methods to solve the over-enhancement problem; however, they have largely ignored the feature loss problem. Therefore, a contrast enhancement algorithm based on gap adjustment for histogram equalization (CegaHE) is proposed. It refers to a visual contrast enhancement algorithm based on histogram equalization (VCEA), which generates visually pleasing enhanced images, and improves the enhancement effects of VCEA. CegaHE adjusts the gaps between two gray values based on the adjustment equation, which takes the properties of human visual perception into consideration, to solve the over-enhancement problem. Besides, it also alleviates the feature loss problem and further enhances the textures in the dark regions of the images to improve the quality of the processed images for human visual perception. Experimental results demonstrate that CegaHE is a reliable method for contrast enhancement and that it significantly outperforms VCEA and other methods.

  18. Contrast-enhanced ultrasound for extrahepatic lesions: preliminary experience

    Energy Technology Data Exchange (ETDEWEB)

    Thorelius, Lars E-mail: lars@thorelius.com

    2004-06-01

    Ultrasound imaging (US) is a convenient, inexpensive and non-invasive investigation. Its use is limited by low sensitivity in the detection of a number of parenchymal lesions, especially those produced by trauma, such as infarctions. Contrast enhancement with SonoVue{sup [reg]} improves the sensitivity of ultrasound in the detection and characterization of focal liver lesions to such an extent, that it may replace computed tomography (CT) and magnetic resonance imaging (MRI). Preliminary experience suggests that SonoVue-enhanced sonography may be useful in the detection of lesions in which blood flow is severely reduced as compared to surrounding parenchyma, such as infarctions, lacerations, hematomas, necrotic tissue and non-vascular cysts, especially in the spleen, kidney and pancreas. This technique can also rule out occlusion of the superior mesenteric, splenic and portal veins, and dilation of the biliary tree. Clinical trials comparing contrast-enhanced sonography with contrast-enhanced computed tomography are warranted to establish the role of this inexpensive and non-invasive technique in the routine work-up of patients with abdominal trauma or presenting with sudden flank pain.

  19. Contrast-enhanced 3D MR DSA for intracranial vessels

    Energy Technology Data Exchange (ETDEWEB)

    Tominaga, Satoru; Ishikura, Reiichi; Ando, Kumiko; Morikawa, Tsutomu; Nakao, Norio [Hyogo Coll. of Medicine, Nishinomiya (Japan); Ikeda, Jyota

    1999-12-01

    We performed serial scans of ultrafast 3D MR angiography sequence which was improved to shorten acquisition time by means of zero-filling interpolation after injection of the contrast medium and called it contrast-enhanced three-dimensional (3D) magnetic resonance (MR) digital subtraction angiography (DSA). The parameters were 3.8/1.3/35 (TR/TE/flip angle), a slab thickness of 60 mm, a voxel size of 2.3 x 1.2 x 3.7 mm, a scan time of 2.9 s. The measurement was sequentially performed for 10 to 15 times after administration of 0.1 mmol/kg of Gd-DTPA. Total acquisition time was almost 30 to 45 s. All images of each set were subtracted with precontrast images and then the maximum intensity projection (MIP) were performed. In all cases, contrast-enhanced 3D MR DSA could clearly depict sequential change of the cranial vessels from the arterial phase to the venous phase. The view from different angle on any phase could be obtained and stereoscopic view was possible. The time intensity curve was obtained from signal intensity measured on the source images. The combination of conventional 3D TOF MRA with contrast-enhanced 3D MR DSA was the useful study which could replace cerebral angiography. (author)

  20. Contrast enhancement pattern in MR imaging of acute cerebral infarction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Deok; Cho, Mee Young; Lee, Chae Guk; Song, Dong Hoon [Inje University College of Medicine, Pusan (Korea, Republic of)

    1994-08-15

    To present the enhancement pattern of acute cerebral or cerebellar cortical infarctions aged 1-3 days on MR. Contrast-enhanced MR images of 26 patients with acute cerebral or cerebellar ischemic events were retrospectively reviewed. MR was performed within 3 days after ictus. Contrast enhancement in the area of infarction was observed in 61.5% (16/26) on MR. Of these 50% (13/26) showed non-parenchymal enhancement (NPE) representing either vascular or leptomeningeal enhancement, 7.7% (2/26) showed parenchymal enhancement (PE), and 2.8% (1/26) showed both NPE and PE. The earliest enhancement was seen in images obtained 12 hours after the onset of symptoms and appeared as NPE. One patient showed NPE without apparent high signal intensity at the corresponding area on T2-weighted images. In 38.5% (10/26), there was no enhancement. Contrast-enhanced MR imaging may be needed in acute ischemic infarction, because NPE may be seen as the earliest MR finding of acute cortical infraction aged 1-3 days.

  1. Visual Contrast Enhancement Algorithm Based on Histogram Equalization

    Directory of Open Access Journals (Sweden)

    Chih-Chung Ting

    2015-07-01

    Full Text Available Image enhancement techniques primarily improve the contrast of an image to lend it a better appearance. One of the popular enhancement methods is histogram equalization (HE because of its simplicity and effectiveness. However, it is rarely applied to consumer electronics products because it can cause excessive contrast enhancement and feature loss problems. These problems make the images processed by HE look unnatural and introduce unwanted artifacts in them. In this study, a visual contrast enhancement algorithm (VCEA based on HE is proposed. VCEA considers the requirements of the human visual perception in order to address the drawbacks of HE. It effectively solves the excessive contrast enhancement problem by adjusting the spaces between two adjacent gray values of the HE histogram. In addition, VCEA reduces the effects of the feature loss problem by using the obtained spaces. Furthermore, VCEA enhances the detailed textures of an image to generate an enhanced image with better visual quality. Experimental results show that images obtained by applying VCEA have higher contrast and are more suited to human visual perception than those processed by HE and other HE-based methods.

  2. Facial nerve palsy: Evaluation by contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Kinoshita, T.; Ishii, K.; Okitsu, T.; Okudera, T.; Ogawa, T.

    2001-01-01

    AIM: The purpose of this study was to investigate the value of contrast-enhanced magnetic resonance (MR) imaging in patients with peripheral facial nerve palsy. MATERIALS AND METHODS: MR imaging was performed in 147 patients with facial nerve palsy, using a 1.0 T unit. All of 147 patients were evaluated by contrast-enhanced MR imaging and the pattern of enhancement was compared with that in 300 control subjects evaluated for suspected acoustic neurinoma. RESULTS: The intrameatal and labyrinthine segments of the normal facial nerve did not show enhancement, whereas enhancement of the distal intrameatal segment and the labyrinthine segment was respectively found in 67% and 43% of patients with Bell's palsy. The geniculate ganglion or the tympanic-mastoid segment was enhanced in 21% of normal controls versus 91% of patients with Bell's palsy. Abnormal enhancement of the non-paralyzed facial nerve was found in a patient with bilateral temporal bone fracture. CONCLUSION: Enhancement of the distal intrameatal and labyrinthine segments is specific for facial nerve palsy. Contrast-enhanced MR imaging can reveal inflammatory facial nerve lesions and traumatic nerve injury, including clinically silent damage in trauma. Kinoshita T. et al. (2001)

  3. Effects of computed tomography contrast medium factors on contrast enhancement

    International Nuclear Information System (INIS)

    Terasawa, Kazuaki; Hatcho, Atsushi; Okuda, Itsuko

    2011-01-01

    The various nonionic iodinated contrast media used in contrast computed tomography (CT) studies differ in terms of their composition, characteristics, and iodine concentration (mgI/ml), as well as the volume injected (ml). Compared with ionic iodinated contrast media, nonionic iodinated contrast media are low-osmolar agents, with different agents having different osmotic pressures. Using a custom-made phantom incorporating a semipermeable membrane, the osmotic flow rate (hounsfield unit (HU)/s) could easily be measured based on the observed increase in CT numbers, and the relationship between the osmotic pressure and the osmotic flow rate could be obtained (r 2 =0.84). In addition, taking the effects of patient size into consideration, the levels of contrast enhancement in the abdominal aorta (AA) and inferior vena cava (IVC) were compared among four types of CT contrast medium. The results showed differences in contrast enhancement in the IVC during the equilibrium phase depending on the type of contrast medium used. It was found that the factors responsible for the differences observed in enhancement in the IVC were the osmotic flow rate and the volume of the blood flow pathways in the circulatory system. It is therefore considered that the reproducibility of contrast enhancement is likely to be reduced in the examination of parenchymal organs, in which scanning must be performed during the equilibrium phase, even if the amount of iodine injected per unit body weight (mgI/kg) is maintained at a specified level. (author)

  4. Therapeutic response assessment of percutaneous radiofrequency ablation for hepatocellular carcinoma: Utility of contrast-enhanced agent detection imaging

    International Nuclear Information System (INIS)

    Kim, Chan Kyo; Choi, Dongil; Lim, Hyo K.; Kim, Seung Hoon; Lee, Won Jae; Kim, Min Ju; Lee, Ji Yeon; Jeon, Yong Hwan; Lee, Jongmee; Lee, Soon Jin; Lim, Jae Hoon

    2005-01-01

    Purpose: To assess the utility of contrast-enhanced agent detection imaging (ADI) in the assessment of the therapeutic response to percutaneous radiofrequency (RF) ablation in patients with hepatocellular carcinoma (HCC). Materials and methods: Ninety patients with a total of 97 nodular HCCs (mean, 2.1 ± 1.3 cm; range, 1.0-5.0 cm) treated with percutaneous RF ablation under the ultrasound guidance were evaluated with contrast-enhanced ADI after receiving an intravenous bolus injection of a microbubble contrast agent (SH U 508A). We obtained serial contrast-enhanced ADI images during the time period from 15 to 90 s after the initiation of the bolus contrast injection. All of the patients underwent a follow-up four-phase helical CT at 1 month after RF ablation, which was then repeated at 2-4 month intervals during a period of at least 12 months. The results of the contrast-enhanced ADI were compared with those of the follow-up CT in terms of the presence or absence of residual unablated tumor and local tumor progression in the treated lesions. Results: On contrast-enhanced ADI, technical success was obtained in 94 (97%) of the 97 HCCs, while residual unablated tumors were found in three HCCs (3%). Two of the three tumors that were suspicious (was not proven) for incomplete ablation were subjected to additional RF ablation. The remaining one enhancing lesion that was suspicious of a residual tumor on contrast-enhanced ADI was revealed to be reactive hyperemia at the 1-month follow-up CT. Therefore; the diagnostic concordance between the contrast-enhanced ADI and 1-month follow-up CT was 99%. Of the 94 ablated HCCs without residual tumors on both the contrast-enhanced ADI and 1-month follow-up CT after the initial RF ablation, five (5%) had CT findings of local tumor progression at a subsequent follow-up CT. Conclusion: Despite its limitations in predicting local tumor progression in the treated tumors, contrast-enhanced ADI is potentially useful for evaluating the

  5. Accuracy of Contrast-enhanced US for Differentiating Benign from Malignant Solid Small Renal Masses.

    Science.gov (United States)

    Atri, Mostafa; Tabatabaeifar, Leila; Jang, Hyun-Jung; Finelli, Anthony; Moshonov, Hadas; Jewett, Michael

    2015-09-01

    To test the hypothesis that qualitative and quantitative features of contrast material-enhanced ultrasonography (US) can be used to differentiate benign from malignant small renal masses. This is an institutional review board approved, HIPAA-compliant prospective study with written informed consent. Patients with histologically characterized solid small renal masses, excluding lipid-rich angiomyolipomas, underwent qualitative contrast-enhanced US with a combination of three different US machines. A subgroup of patients underwent quantitative contrast-enhanced US. Patients received a bolus injection of 0.2 mL of contrast material for qualitative and quantitative evaluations and were followed for 3 minutes. Two radiologists independently reviewed videotaped qualitative contrast-enhanced US examinations and were blinded to the final diagnoses. Features that were evaluated included lesion vascularity relative to the adjacent cortex in the arterial phase, the presence of a capsule, homogeneity, the pattern of vascularity, and washout. One radiologist separately reviewed a subset of contrast-enhanced US examinations that were performed with all three machines. Parameters of a first-pass time intensity curve were calculated for quantitative analysis. The Mann-Whitney test was used for quantitative parameters, the χ(2) or Fisher exact test was used for qualitative parameters, and κ statistics and Fleiss methodology were used to determine interobserver and intermachine agreement. The study population consisted of 91 patients (35 women and 56 men) with 94 lesions. The mean age was 62 years ± 14 (range, 21-91). Three patients had two lesions each, which were evaluated at two different sessions. There were 26 benign small renal masses (including 18 oncocytomas, seven lipid-poor angiomyolipomas, and one hemangioblastoma) and 68 malignant masses (including 41 clear cell, 20 papillary, and seven chromophobe renal cell carcinomas [RCCs[) that were 1.1-4.0 cm in diameter (mean

  6. Contrast-enhanced MR enterography as a stand-alone tool to evaluate Crohn's disease in a paediatric population

    International Nuclear Information System (INIS)

    Spieler, B.; Hindman, N.; Levy, J.; Zabrieski, K.; Sahlein, D.; Seuss, C.; Kim, S.

    2013-01-01

    Aim: To assess the performance of contrast-enhanced T1-weighted magnetic resonance imaging (MRI) alone in the evaluation of Crohn's disease in comparison to all magnetic resonance enterography (MRE) imaging sequences together in an attempt to suggest limitation of the number of overall unenhanced sequences need for the follow-up evaluation. Materials and methods: Twenty-five paediatric patients (mean age 14.1 ± 3.7 years, male = 12, female = 13) underwent MRE at 1.5 T for evaluation of Crohn's disease. Two radiologists reviewed only contrast-enhanced T1-weighted images in consensus on the first session. Whole images including unenhanced (steady-state free precession, single-shot fast spin-echo (HASTE), fat-suppressed T2-weighted) and contrast-enhanced T1-weighted sequences were reviewed in consensus during the second session with a 1 month interval, which was used as a reference standard. The readers evaluated the presence or absence of disease in 10 bowel segments in each patient. For the abnormal bowel segments, the readers then evaluated for active versus inactive disease and for the presence or absence of abscess. Sensitivity, specificity, and overall accuracy were calculated for detecting active inflammation. Results: There were 53/250 bowel segments with active inflammation using the reference standard imaging method. The sensitivity, specificity, and accuracy for diagnosing active inflammation using contrast-enhanced images alone were 83.3%, 86.9%, and 84.9%. In five of the false-positive cases of detecting abscess from contrast-enhanced imaging alone, absence of abscesses was confirmed on the non-fat-suppressed HASTE images. Conclusion: The number of MRE sequences in paediatric Crohn's patients can be decreased while maintaining diagnostic accuracy using contrast-enhanced T1 and non-fat-suppressed HASTE images

  7. Imaging microvasculature with contrast-enhanced ultraharmonic ultrasound

    NARCIS (Netherlands)

    D. Maresca (David); I. Skachkov (Ilya); G. Renaud (G.); K. Jansen (Krista); G. van Soest (Gijs); N. de Jong (Nico); A.F.W. van der Steen (Ton)

    2014-01-01

    textabstractAtherosclerotic plaque neovascularization was shown to be one of the strongest predictors of future cardiovascular events. Yet, the clinical tools for coronary wall microvasculature detection invivo are lacking. Here we report an ultrasound pulse sequence capable of detecting

  8. The Application of Contrast Enhanced Ultrasound in Molecular Imaging

    International Nuclear Information System (INIS)

    Lee, Hak Jong; Chung, Jin Haeung; Hwang, Sung Il

    2009-01-01

    Microbubble contrast agent for ultrasound imaging has come of age, adding entirely new capabilities to real time ultrasound imaging. These new ultrasound imaging techniques exploit the nonlinear echoes that result from the unique interaction between ultrasound and microbubbles, which are readily distinguishable from the echoes of tissues. Contrast enhanced ultrasound can be used to quantify both flow rate and relative vascular volume of the microvasculature in solid lesions or organs, which makes it possible for it to be one of the modalities in molecular imaging. Angiogenesis is one of the important processes contributing to new blood vessel growth that occurs in a variety of physiologic and pathophysiologic states. It is essential for spread and growth of malignant tumors. The advantages of contrast enhanced ultrasound are that it is a noninvasive method for observing tumor angiogenesis. Sonoporation utilizes the interaction of ultrasound with ultrasound contrast agents to temporarily permeabilized the cell membrane allowing for the uptake of DNA, drugs, and other therapeutic compounds from the extracellular environment. Thus, sonoporation is a promising drug delivery and gene therapy technique, limited only by lack of understanding regarding the biophysical mechanism that results in the cell membrane permeability change. In conclusion, ultrasound contrast agent could have a role not only in the molecular imaging field with the advantage of noninvasive quantification of angiogenesis, but also in the field of drug treatment of cells using sonoporation

  9. Fuzzy Logic-Based Histogram Equalization for Image Contrast Enhancement

    Directory of Open Access Journals (Sweden)

    V. Magudeeswaran

    2013-01-01

    Full Text Available Fuzzy logic-based histogram equalization (FHE is proposed for image contrast enhancement. The FHE consists of two stages. First, fuzzy histogram is computed based on fuzzy set theory to handle the inexactness of gray level values in a better way compared to classical crisp histograms. In the second stage, the fuzzy histogram is divided into two subhistograms based on the median value of the original image and then equalizes them independently to preserve image brightness. The qualitative and quantitative analyses of proposed FHE algorithm are evaluated using two well-known parameters like average information contents (AIC and natural image quality evaluator (NIQE index for various images. From the qualitative and quantitative measures, it is interesting to see that this proposed method provides optimum results by giving better contrast enhancement and preserving the local information of the original image. Experimental result shows that the proposed method can effectively and significantly eliminate washed-out appearance and adverse artifacts induced by several existing methods. The proposed method has been tested using several images and gives better visual quality as compared to the conventional methods.

  10. Characterisation of focal liver lesions with contrast enhanced ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, Christoph F. E-mail: christoph.dietrich@ckbm.de

    2004-06-01

    Ultrasound contrast agents (USCA) have improved the detection rate of liver tumours in recent years. Conventional ultrasound has been reported to be relatively unreliable in the characterisation of liver tumours. SonoVue{sup [reg]} (Bracco Imaging Spa) has been shown to be particularly advantageous in the differentiation of benign and malignant liver tumours and, therefore, possibly represents a new cost-effective competitive alternative to other liver imaging modalities (e.g. computed tomography and magnetic resonance imaging), thus allowing these important technologies to be available for other indications (e.g. brain, thorax). More detailed and specific liver tumour characterisation is possible in about 80% of liver tumours due to typical vascularity and perfusion patterns. The role of USCA for better characterisation, which is possible through the analysis of flow characteristics in real time, places a particular emphasis on agent use. Contrast enhanced real-time imaging techniques with SonoVue{sup [reg]} allow real-time analysis of tumour perfusion in patients with liver lesions. Liver tumours known to be hyperperfused in the arterial phase (e.g. focal nodular hyperplasia, hepatocellular adenoma and carcinoma, and hyperperfused metastases) can be better detected and characterised. Hypoperfused tumours (e.g. liver metastases of the gastrointestinal tract) can be recognised in the portal venous phase as less perfused 'black spots'. In this article we discuss liver tumour characterisation by contrast enhanced ultrasonography.

  11. Adaptive sigmoid function bihistogram equalization for image contrast enhancement

    Science.gov (United States)

    Arriaga-Garcia, Edgar F.; Sanchez-Yanez, Raul E.; Ruiz-Pinales, Jose; Garcia-Hernandez, Ma. de Guadalupe

    2015-09-01

    Contrast enhancement plays a key role in a wide range of applications including consumer electronic applications, such as video surveillance, digital cameras, and televisions. The main goal of contrast enhancement is to increase the quality of images. However, most state-of-the-art methods induce different types of distortion such as intensity shift, wash-out, noise, intensity burn-out, and intensity saturation. In addition, in consumer electronics, simple and fast methods are required in order to be implemented in real time. A bihistogram equalization method based on adaptive sigmoid functions is proposed. It consists of splitting the image histogram into two parts that are equalized independently by using adaptive sigmoid functions. In order to preserve the mean brightness of the input image, the parameter of the sigmoid functions is chosen to minimize the absolute mean brightness metric. Experiments on the Berkeley database have shown that the proposed method improves the quality of images and preserves their mean brightness. An application to improve the colorfulness of images is also presented.

  12. Blunt splenic trauma: can contrast enhanced sonography be used for the screening of delayed pseudoaneurysms?

    Science.gov (United States)

    Poletti, Pierre-Alexandre; Becker, Christoph D; Arditi, Daniel; Terraz, Sylvain; Buchs, Nicolas; Shanmuganathan, Kathirkamanathan; Platon, Alexandra

    2013-11-01

    To assess the value of contrast-enhanced sonography (CES) for the detection of delayed post-traumatic splenic pseudo-aneurysms, usually considered an indication for angiographic embolization. Sixty-three consecutive hemodynamically stable trauma patients in whom admission CT displayed a splenic injury of grade II or higher (AAST classification), without evidence of vascular involvement, were included in the study. CES of the spleen using a second generation contrast agent was systematically performed within 48-72 h after admission, for the detection of a pooling of contrast media suggestive of pseudoaneurysm. Within 6h after contrast-enhanced sonography, all patients underwent an abdominal CT for control purposes. CES results were compared to CT findings, which were considered the reference standard. This study received approval from the institutional ethical board. CES showed a blush of contrast consistent with a pseudoaneurysm in 6 of the 63 patients. All were confirmed at subsequent control CT. Pooling of contrast was found at CT in 2 patients in whom contrast-enhanced sonography was negative. There was no false positive CES examination for the suspicion of pseudoaneurysms. When compared to CT, the sensitivity, specificity, positive and negative predictive values of CES to suggest a pseudoaneurysms, were 75% (6/8), 100% (55/55), 100% (6/6), and 96% (55/57), respectively. Our data suggest that CES may be useful for the screening of delayed traumatic splenic pseudoaneurysms: if a negative CES does not absolutely rule out a pseudoaneurysm, a positive CES warrants an angiography, without need of control CT. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Contrast-enhanced MRI findings of the knee in healthy children; establishing normal values.

    Science.gov (United States)

    Hemke, Robert; van den Berg, J Merlijn; Nusman, Charlotte M; van Gulik, E Charlotte; Barendregt, Anouk M; Schonenberg-Meinema, Dieneke; Dolman, Koert M; Kuijpers, Taco W; Maas, Mario

    2018-03-01

    To define normative standards for the knee in healthy children using contrast-enhanced MRI, focusing on normal synovial membrane thickness. Secondly, presence of joint fluid and bone marrow oedema was evaluated. For this study, children without disorders potentially resulting in (accompanying) arthritis were included. Patients underwent clinical assessments, followed by contrast-enhanced MRI. MRI features were evaluated in consensus using the Juvenile Arthritis MRI Scoring (JAMRIS) system. Additionally, the presence of joint fluid was evaluated. No cartilage lesions or bone abnormalities were observed. We included 57 healthy children. The overall mean thickness of the normal synovial membrane was 0.4 mm (min-max; 0.0-1.8mm). The synovium was thickest around the cruciate ligaments and retropatellar and suprapatellar regions. The mean overall diameter of the largest pocket of joint fluid was 2.8 mm (min-max; 0.9-8.0mm). Bone marrow changes were observed in three children (all in the apex patellae). The normal synovial membrane was maximally 1.8 mm thick, indicating that the JAMRIS cut-off value of 2 mm can be considered a valid measure for evaluating synovial hypertrophy. Some joint fluid and bone marrow changes suggestive of bone marrow oedema in the apex patellae can be seen in healthy children. • Knowledge on the normal synovial appearance using contrast-enhanced MR is lacking. • In healthy children, normal synovial membrane is maximally 1.8 mm thick. • Normal synovium is thickest around the cruciate ligaments, retropatellar and suprapatellar. • Bone marrow oedema in the apex patellae is seen in healthy children.

  14. Blunt splenic trauma: Can contrast enhanced sonography be used for the screening of delayed pseudoaneurysms?

    Energy Technology Data Exchange (ETDEWEB)

    Poletti, Pierre-Alexandre, E-mail: Pierre-Alexandre.Poletti@hcuge.ch [Department of Radiology, University Hospital of Geneva, 4 Rue Gabrielle Perret-Gentil, 1211 Geneva 14 (Switzerland); Becker, Christoph D.; Arditi, Daniel; Terraz, Sylvain [Department of Radiology, University Hospital of Geneva, 4 Rue Gabrielle Perret-Gentil, 1211 Geneva 14 (Switzerland); Buchs, Nicolas [Department of Surgery, University Hospital of Geneva, 4 Rue Gabrielle Perret-Gentil, 1211 Geneva 14 (Switzerland); Shanmuganathan, Kathirkamanathan [Department of Diagnostic Radiology and Nuclear Medicine, 22 S. Greene Street, Baltimore, MD 21201 (United States); Platon, Alexandra [Department of Radiology, University Hospital of Geneva, 4 Rue Gabrielle Perret-Gentil, 1211 Geneva 14 (Switzerland)

    2013-11-01

    Purpose: To assess the value of contrast-enhanced sonography (CES) for the detection of delayed post-traumatic splenic pseudo-aneurysms, usually considered an indication for angiographic embolization. Methods: Sixty-three consecutive hemodynamically stable trauma patients in whom admission CT displayed a splenic injury of grade II or higher (AAST classification), without evidence of vascular involvement, were included in the study. CES of the spleen using a second generation contrast agent was systematically performed within 48–72 h after admission, for the detection of a pooling of contrast media suggestive of pseudoaneurysm. Within 6 h after contrast-enhanced sonography, all patients underwent an abdominal CT for control purposes. CES results were compared to CT findings, which were considered the reference standard. This study received approval from the institutional ethical board. Results: CES showed a blush of contrast consistent with a pseudoaneurysm in 6 of the 63 patients. All were confirmed at subsequent control CT. Pooling of contrast was found at CT in 2 patients in whom contrast-enhanced sonography was negative. There was no false positive CES examination for the suspicion of pseudoaneurysms. When compared to CT, the sensitivity, specificity, positive and negative predictive values of CES to suggest a pseudoaneurysms, were 75% (6/8), 100% (55/55), 100% (6/6), and 96% (55/57), respectively. Conclusion: Our data suggest that CES may be useful for the screening of delayed traumatic splenic pseudoaneurysms: if a negative CES does not absolutely rule out a pseudoaneurysm, a positive CES warrants an angiography, without need of control CT.

  15. Sepsis patients' renal manifestation on contrast-enhanced CT

    International Nuclear Information System (INIS)

    Sasaguri, K.; Yamaguchi, K.; Nakazono, T.; Mizuguchi, M.; Irie, H.

    2016-01-01

    Aim: To evaluate renal volume and attenuation changes in patients with sepsis on contrast-enhanced computed tomography (CT) with respect to the severity of sepsis. Materials and methods: Forty-four patients with sepsis who underwent CT before and after the onset of sepsis were retrospectively analysed. Renal volume and CT attenuation value of the renal cortex on contrast-enhanced CT were measured for each patient and changes in renal volume and CT attenuation value from before to after the onset of sepsis were calculated. The changes were correlated with the severity of sepsis (Sepsis-related Organ Failure Assessment [SOFA] score). The time course of the renal volume and CT attenuation changes were also evaluated. Results: Renal volume increased by 17.6% and CT attenuation value decreased by 19% after the onset of sepsis with statistically significant differences (p<0.001 for both renal volume and CT attenuation changes). The renal volume and CT attenuation changes had significant correlations with the SOFA score (r=0.36, p=0.018 and −0.43, p=0.005, respectively). The time course of the renal volume and CT attenuation changes seemed to be gradual compared to that of the SOFA score and to lag behind the peak of the SOFA score. Conclusion: In patients with sepsis, the renal volume increases and the CT attenuation value decreases in proportion to the severity of sepsis. The changes may lag behind the peak of severity of sepsis and can be observed for a relatively long time after a patient's recovery from sepsis. - Highlights: • The renal volume increases and the renal enhancement on contrast-enhanced CT decreases in patients with sepsis. • The degrees of these changes are correlated with severity of sepsis. • These changes may lag behind the peak of severity of sepsis and last for a long time after a patient's recovery from sepsis.

  16. Evaluation of residual hepatocellular carcinoma after transcatheter arterial chemoembolization: Comparison between contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography

    International Nuclear Information System (INIS)

    Kim, Seung Hoon; Lim, Hyo Keun; Lee, Won Jae

    2001-01-01

    To evaluate the effectiveness of contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography (PDUS) in assessing the therapeutic effect of transcatheter arterial chemoembolization (TACE) in hepatocellular carcinomas (HCCs). The follow-up contrast-enhanced helical CT and contrast-enhanced PDUS were performed for twenty-nine nodular HCCs from twelve patients previously treated with TACE. We defined the residual HCCs as intratumoral enhancing area on contrast-enhanced helical CT and color signal on contrast-enhanced PDUS. The interval between two examinations was less than 2 weeks (mean, 9 days). Two radiologists evaluated two examinations by consensus, and the results of these two examination were compared with the findings of other examinations including CT, angiography, and/or pathology to calculate the sensitivity, specificity and accuracy of two examinations. Of the 29 HCCs, 20 had residual HCCs whereas no residual HCCs in 9 HCCs on pathologic examination and/or follow-up radiologic study. The sensitivity, sensitivity and accuracy of contrast-enhanced helical CT were 65 (13/20), 89 (8/9), and 72% (21/29) while those of contrast-enhanced PDUS were 100 (20/20), 89 (8/9) and 97% (28/29), respectively. A microbubble contrast-enhanced PDUS was more effective in the detection of residual tumor in HCCs following TACE than contrast-enhanced helical CT.

  17. Three-dimensional computed tomography angiography of coronary artery bypass graft with electron beam tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hoshi, Toshiko; Yamauchi, Tatsuo; Kanauchi, Tetsu; Konno, Miyuki; Imai, Kamon; Suwa, Jiro; Onoguchi, Katsuhisa; Hashimoto, Kazuhiro; Horie, Toshinobu [Saitama Cardiovascular and Respiratory Center, Konan (Japan)

    2001-10-01

    Assessment of coronary artery bypass graft patency by three-dimensional reconstructed computed tomography angiography (3D-CTA) derived from electrocardiography-gated contrast-enhanced electron beam tomography (EBT) was evaluated. Thirty-nine patients with 99 grafts (45 arterial grafts and 54 venous grafts) underwent 3D-CTA and selective coronary angiography within a 3-week interval. 3D-CTA images of the coronary bypass grafts were compared with the coronary angiography images used as the control. 3D-CTA defined 42 of 44 arterial grafts as patent (sensitivity: 95%), all 47 venous grafts as patent (sensitivity: 100%) and all 7 venous grafts as occlusive (specificity: 100%). The overall sensitivity and specificity were 98% and 88%, respectively. 3D-CTA is an useful noninvasive technique with adequate sensitivity and specificity to assess coronary artery bypass graft patency. (author)

  18. Contrast-enhanced ultrasound features of histologically proven focal nodular hyperplasia: diagnostic performance compared with contrast-enhanced CT

    International Nuclear Information System (INIS)

    Wang, Wei; Chen, Li-Da; Liu, Guang-Jian; Xu, Zuo-Feng; Xie, Xiao-Yan; Wang, Yan; Zhou, Lu-Yao; Lu, Ming-De; Shen, Shun-Li

    2013-01-01

    To investigate and compare contrast-enhanced ultrasound (CEUS) in the characterisation of histologically proven focal nodular hyperplasia (FNH) with contrast-enhanced computed tomography (CECT). CEUS was performed in 85 patients with 85 histologically proven FNHs. Enhancement, centrifugal filling, spoke-wheel arteries, feeding artery and central scarring were reviewed and correlated with lesion size or liver background. Independent factors for predicting FNH from other focal liver lesions (FLLs) were evaluated. Forty-seven FLLs with CECT were randomly selected for comparison of diagnostic performance with CEUS. Centrifugal filling was more common (P = 0.002) and the significant predictor (P = 0.003) in FNHs ≤3 cm. Lesion size or liver background has no significant influence on the detection rate of the spoke-wheel arteries and feeding artery (P > 0.05). Central scarring was found in 42.6 % of FNHs ≥3 cm (P = 0.000). The area under the ROC curve, sensitivity and specificity showed no significant differences between CEUS and CECT (P > 0.05), except that the sensitivity of CEUS was better for reader 1 (P = 0.041). CEUS is valuable in characterising centrifugal filling signs or spoke wheels in small FNHs and should be employed as the first-line imaging technique for diagnosis of FNH. (orig.)

  19. Assessment of contrast-enhanced ultrasonography in diagnosis and preoperative localization of insulinoma

    International Nuclear Information System (INIS)

    An Lichun; Li Wenxiu; Yao Kechun; Liu Rong; Lv Faqin; Tang Jie; Zhang Sunxin

    2011-01-01

    Objective: This study was to evaluate the value of contrast-enhanced ultrasonography (CEUS) in the diagnosis and preoperative localization of insulinoma and explore the enhancement patterns of the tumors. Methods: Unenhanced and contrast-enhanced ultrasonographic examinations of 31 patients who underwent resection of insulinomas were retrospectively reviewed. The diagnosis sensitivity and localization specificity of CEUS for insulinomas were determined. Results of unenhanced ultrasonography and CEUS were compared by Chi-square test. Results: Unenhanced ultrasonography could display 9 of 37 (24.3%) surgically verified insulinomas in 31 patients, while the diagnosis sensitivity and localization specificity of preoperative CEUS was 33 (89.2%) and 32 (86.5%) of the 37 tumors, respectively. In contrast to the unenhanced ultrasonography, the improvement of CEUS in the diagnosis and preoperative localization of insulinomas was significant (p < 0.0001). The enhancement pattern of insulinoma on CEUS was fast wash-in and slow wash-out. All the tumors were homogeneous hypervascularity in the earlier arterial phase, while the tumors still displayed hyperenhancing pattern in the late phase. Conclusion: Our study demonstrates the great potential of CEUS in the diagnosis and preoperative localization of insulinomas. Since CEUS is a convenient, inexpensive, effective and non-invasive modality, the study supports the use of CEUS as a primary tool in the evaluation of patients with insulinomas.

  20. Atherosclerotic Carotid Plaques: Multimodality Imaging with Contrast-enhanced Ultrasound, Computed Tomography, and Magnetic Resonance Imaging.

    Science.gov (United States)

    Hingwala, Divyata R; Chandrasekhakan, Kesavadas; Thomas, Bejoy; Sylaja, P N; Unnikrishnan, M; Kapilamoorthy, T R

    2017-01-01

    The imaging of carotid plaques has undergone a paradigm shift increasing importance being given to plaque characterization. Patients with "vulnerable" plaques are more prone to develop future neurovascular events. The purpose of this study is to analyze the role of multimodality imaging techniques in the assessment of carotid atherosclerotic plaques. Twenty-six patients were prospectively enrolled in the study. Patients underwent multidetector computed tomography (CT) angiography, ultrasound, contrast-enhanced ultrasound, and high-resolution magnetic resonance imaging (MRI) of the carotid arteries with special emphasis on the carotid bifurcation. The mean age of patients was 65.41 years. Twenty-one were males. Plaque neovascularization was seen in 10 of the 18 plaques studied (55.56%). Based on the predominant components of the plaque, plaques were characterized as lipid (3), lipid with recent hemorrhage (1), fibrous (7), fibrofatty (4), fibrofatty with some hemorrhagic components (3), and recent hemorrhage (2). Together, contrast-enhanced ultrasound, CT, and MRI provide complete information about the plaque characteristics.

  1. Renal masses - evaluation by amplitude coded colour Doppler sonography and multiphasic contrast-enhanced CT

    International Nuclear Information System (INIS)

    Riccabona, M.; Szolar, D.; Preidler, K.; Uggowitzer, M.; Kugler, C.; Doerfler, O.; Schreyer, H.H.

    1999-01-01

    Objective: To assess the efficacy of amplitude coded colour Doppler US (aCDS) in the evaluation of renal masses as shown by multiphasic contrast-enhanced CT. Material and methods: Eighty patients (155 kidneys) with suspicion of renal masses underwent aCDS and spiral CT. The findings were classified into normal kidneys, kidneys with tumours, kidneys with cysts, and those with 'other findings' (i.e. bleeding, calcifications, inflammation, parenchymal hypertrophy). The aCDS findings were compared to CT results and to histological findings or clinical, laboratory and follow-up data. Results: Eighteen renal cell carcinomas and 8 other tumours were found; 78 kidneys had cysts, 12 polycystic kidneys and 10 fibrotic kidneys were detected, 20 kidneys showed other findings. Diagnostic aCDS data were obtained in 129 kidneys (83.2%) showing pathology with an accuracy of 94%. CT adequately showed pathology in all patients with some diagnostic uncertainty in the evaluation of complicated cysts. Conclusion: Though contrast-enhanced multiphasic spiral CT is the method of choice for evaluating renal masses, US including aCDS can provide valuable information, particularly in differentiating vascularized from non-vascularized lesions and in the evaluation of complicated renal cysts. (orig.)

  2. Coronary-to-bronchial artery fistula in a patient with multivessel coronary disease treated by percutaneous coronary intervention.

    Science.gov (United States)

    Rigattieri, Stefano; Fedele, Silvio; Sperandio, Massimiliano; Martuscelli, Eugenio; Simonetti, Giovanni; Altamura, Giuliano; Loschiavo, Paolo

    2010-08-01

    We describe the case of a 78-year-old patient, admitted to our hospital with an acute coronary syndrome. Coronary angiography showed multivessel coronary artery disease and an anomalous coronary vessel branching from the right coronary artery. After successful percutaneous revascularization and discharge, the anomalous vessel was diagnosed by contrast enhanced 64-multidetector computed tomography as a coronary-to-bronchial fistula. Since the patient was asymptomatic, conservative treatment was selected.

  3. Contrast-Enhanced Ultrasonography in Crohn's Disease Diagnostics.

    Science.gov (United States)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Liebert, Ariel; Kłopocka, Maria; Serafin, Zbigniew

    2015-06-01

    The chronic nature of Crohn's disease (CD) implicates necessity of multiple control assessments throughout patient's life. It is accepted that in patients with CD requiring disease monitoring, magnetic resonance enterography (MRE) and computed tomography enterography (CTE) are--apart from endoscopy--imaging studies of first choice. In practice, diagnostic imaging of patients with CD is troublesome, since MRE is an expensive and complicated study, and CTE exposes patients to high doses of ionizing radiation. Therefore, there is a need for new, both non-invasive and effective, methods of imaging in CD. Contrast-Enhanced Ultrasonography (CEUS) is a relatively new method using gas-filled microbubbles serving as contrast agent. It allows for detailed assessment of blood perfusion within intestine wall and peri-intestinal tissues, which enables detection and monitoring of inflammation and its qualitative assessment. The purpose of this paper is to describe CEUS examination technique and its clinical applications in patients with Crohn's disease.

  4. Dynamic Contrast-Enhanced CT in Patients with Pancreatic Cancer

    DEFF Research Database (Denmark)

    Eriksen, Rie Ø; Strauch, Louise S; Sandgaard, Michael

    2016-01-01

    tissue, compared with measurements in pancreatic tissue outside of tumor, or normal pancreatic tissue in control groups of healthy volunteers. The studies were heterogeneous in the number of patients enrolled and scan protocols. Perfusion parameters measured and analyzed by DCE-CT might be useful......The aim of this systematic review is to provide an overview of the use of Dynamic Contrast-enhanced Computed Tomography (DCE-CT) in patients with pancreatic cancer. This study was composed according to the PRISMA guidelines 2009. The literature search was conducted in PubMed, Cochrane Library...... in the investigation of characteristic vascular patterns of exocrine pancreatic tumors. Further clinical studies are desired for investigating the potential of DCE-CT in pancreatic tumors....

  5. Design of a clinical vein contrast enhancing projector

    Science.gov (United States)

    Zeman, Herbert D.; Lovhoiden, Gunnar; Deshmukh, Harshal

    2001-06-01

    A clinical study has been initiated to compare an experimental IR device, the Vein Contrast Enhancer (VCE), with standard techniques for finding veins for venipuncture. The aims of this proposal are (1) to evaluate the performance of the VCE in a clinical setting, specifically by comparing its sensitivity of detection with existing vein-finding techniques used by experienced nurses or phlebotomists, (2) to study its usefulness in subjects who are obese, who have difficult venous access or thrombosed veins, or whose veins are not visible or difficult to palpate, and (3) to show that it performs as well on subjects with darkly pigmented skin as on subjects with lightly pigmented skin. The VCE will first be studied in adult subjects, and then in pediatric subjects.

  6. Contrast Enhanced MRI in the Diagnosis of HCC.

    Science.gov (United States)

    Niendorf, Eric; Spilseth, Benjamin; Wang, Xiao; Taylor, Andrew

    2015-09-21

    Hepatocellular carcinoma (HCC) is the 6th most common cancer worldwide. Imaging plays a critical role in HCC screening and diagnosis. Initial screening of patients at risk for HCC is performed with ultrasound. Confirmation of HCC can then be obtained by Computed Tomography (CT) or Magnetic Resonance Imaging (MRI), due to the relatively high specificity of both techniques. This article will focus on reviewing MRI techniques for imaging HCC, felt by many to be the exam of choice for HCC diagnosis. MRI relies heavily upon the use of gadolinium-based contrast agents and while primarily extracellular gadolinium-based contrast agents are used, there is an emerging role of hepatobiliary contrast agents in HCC imaging. The use of other non-contrast enhanced MRI techniques for assessing HCC will also be discussed and these MRI strategies will be reviewed in the context of the pathophysiology of HCC to help understand the MR imaging appearance of HCC.

  7. Value of contrast-enhanced ultrasound in rheumatoid arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Zordo, Tobias de; Mlekusch, Sabine P.; Feuchtner, Gudrun M. [Department of Radiology II, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria); Mur, Erich [Department of Internal Medicine, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria); Schirmer, Michael [Department of Internal Medicine, Hospital of the Elisabethines Klagenfurt, Voelkermarkter Strasse 15-19, 9020 Klagenfurt (Austria); Klauser, Andrea S. [Department of Radiology II, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria)], E-mail: andrea.klauser@i-med.ac.at

    2007-11-15

    The purpose of this review is to describe the spectrum of sonographic findings in rheumatic diseases with respect to the diagnostic potential using US contrast media which prove activity or inactivity in synovial tissue where new treatment regimes target. Synovial activity can be found in non-erosive and erosive forms of primary and secondary osteoarthritis, and in inflammatory forms of joint diseases like rheumatoid arthritis and peripheral manifestations of spondyloarthritis including, ankylosing spondylitis, Reiter's syndrome, psoriatic arthritis and enteropathic arthritis. It can also be present in metabolic and endocrine forms of arthritis, in connective tissue arthropathies like systemic lupus erythematosus or scleroderma and in infectious arthritis. Ultrasound should be used as first-line imaging modality in suspected early cases of RA and other forms of arthritis, whereas contrast-enhanced ultrasound (CEUS) can further enable for sensitive assessment of vascularity which correlates with disease activity.

  8. Contrast-enhanced imaging of cerebral vasculature with laser speckle.

    Science.gov (United States)

    Murari, K; Li, N; Rege, A; Jia, X; All, A; Thakor, N

    2007-08-01

    High-resolution cerebral vasculature imaging has applications ranging from intraoperative procedures to basic neuroscience research. Laser speckle, with spatial contrast processing, has recently been used to map cerebral blood flow. We present an application of the technique using temporal contrast processing to image cerebral vascular structures with a field of view a few millimeters across and approximately 20 microm resolution through a thinned skull. We validate the images using fluorescent imaging and demonstrate a factor of 2-4 enhancement in contrast-to-noise ratios over reflectance imaging using white or spectrally filtered green light. The contrast enhancement enables the perception of approximately 10%-30% more vascular structures without the introduction of any contrast agent.

  9. Image contrast enhancement based on a local standard deviation model

    International Nuclear Information System (INIS)

    Chang, Dah-Chung; Wu, Wen-Rong

    1996-01-01

    The adaptive contrast enhancement (ACE) algorithm is a widely used image enhancement method, which needs a contrast gain to adjust high frequency components of an image. In the literature, the gain is usually inversely proportional to the local standard deviation (LSD) or is a constant. But these cause two problems in practical applications, i.e., noise overenhancement and ringing artifact. In this paper a new gain is developed based on Hunt's Gaussian image model to prevent the two defects. The new gain is a nonlinear function of LSD and has the desired characteristic emphasizing the LSD regions in which details are concentrated. We have applied the new ACE algorithm to chest x-ray images and the simulations show the effectiveness of the proposed algorithm

  10. Magnetic iron oxide for contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Fahlvik, A.K.

    1991-05-01

    The main objective of this experimental work has been to study the biological fate and the contrast enhancing potential of a model preparation of magnetic iron oxide (MSM) after intravenous injection to rodents. This was achieved by: Studying in vitro contrast efficacy of various magnetic iron oxide preparations by relaxation analysis. Studying in vivo contrast efficacy of MSM by relaxation analysis and NMR imaging. Studying the biodistribution and bioelimination of MSM in independent experiments using relaxation analysis, radioactivity studies and histological techniques. Studying interactions of MSM with target cells and target organelles using ex vivo techniques. Based on the presented experimental study, the MSM model preparation of magnetic iron oxide seems to fulfill basic requirements of NMR contrast agents: efficient proton relaxation, specific in vivo distribution, and biological tolerance. 177 refs., 5 figs., 2 tabs

  11. Contrast-enhanced microwave detection and treatment of breast cancer

    Science.gov (United States)

    Gao, Fuqiang

    Contrast agents and heating agents have been proposed for microwave breast tumor imaging and treatment, respectively. The dielectric properties of the tumor are altered with contrast agents or heating agents that locally accumulate in the tumor. The resulting change in dielectric properties of the tumor has the potential to enhance the sensitivity of microwave imaging of breast tumors and increase the efficiency and selectivity of microwave thermal therapy of breast tumors. This dissertation addresses several key challenges in contrast-enhanced microwave imaging and treatment of breast tumors. Carbon nanotubes (CNTs) have been shown to enhance both the relative permittivity and effective conductivity of the host medium, and are promising as theranostic (integrated therapeutic and diagnostic) agents. Thus, our properties characterization work focuses on CNT dispersions. We performed in vitro microwave dielectric properties and heating response characterization of dispersions of CNTs treated by different functionalization methods and identified a CNT formulation that is very promising as a microwave theranostic agent. Stable dispersions of CNTs with concentrations up to 20 mg/ml are obtained with this formulation, and the enhanced microwave properties of these dispersions are extraordinary compared to the control. We also conducted in vivo dielectric properties characterization of mouse tumors with intra-tumoral injections of CNT dispersions and confirmed that the presence of CNTs increases the dielectric properties of the tumor. In parallel, we developed a contrast-enhanced microwave breast tumor imaging algorithm using sparse reconstruction methods. We demonstrated that this algorithm accurately localizes small tumors in 3D numerical breast phantoms. We also demonstrated the experimental feasibility of this method using physical breast phantoms. Lastly, we studied the sensitivity of the distorted Born iterative method (DBIM) to initial guesses and developed a

  12. Vascular applications of contrast-enhanced ultrasound imaging.

    Science.gov (United States)

    Mehta, Kunal S; Lee, Jake J; Taha, Ashraf A; Avgerinos, Efthymios; Chaer, Rabih A

    2017-07-01

    Contrast-enhanced ultrasound (CEUS) imaging is a powerful noninvasive modality offering numerous potential diagnostic and therapeutic applications in vascular medicine. CEUS imaging uses microbubble contrast agents composed of an encapsulating shell surrounding a gaseous core. These microbubbles act as nearly perfect intravascular reflectors of ultrasound energy and may be used to enhance the overall contrast and quality of ultrasound images. The purpose of this narrative review is to survey the current literature regarding CEUS imaging and discuss its diagnostic and therapeutic roles in current vascular and selected nonvascular applications. The PubMed, MEDLINE, and Embase databases were searched until July 2016 using the PubMed and Ovid Web-based search engines. The search terms used included contrast-enhanced, microbubble, ultrasound, carotid, aneurysm, and arterial. The diagnostic and therapeutic utility of CEUS imaging has grown exponentially, particularly in the realms of extracranial carotid arterial disease, aortic disease, and peripheral arterial disease. Studies have demonstrated that CEUS imaging is diagnostically superior to conventional ultrasound imaging in identifying vessel irregularities and measuring neovascularization to assess plaque vulnerability and end-muscle perfusion. Groups have begun to use microbubbles as agents in therapeutic applications for targeted drug and gene therapy delivery as well as for the enhancement of sonothrombolysis. The emerging technology of microbubbles and CEUS imaging holds considerable promise for cardiovascular medicine and cancer therapy given its diagnostic and therapeutic utility. Overall, with proper training and credentialing of technicians, the clinical implications are innumerable as microbubble technology is rapidly bursting onto the scene of cardiovascular medicine. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  13. Contrast Enhancement of Mammograms for Rapid Detection of Microcalcification Clusters

    Directory of Open Access Journals (Sweden)

    Hajar Moradmand

    2014-08-01

    Full Text Available Introduction Breast cancer is one of the most common types of cancer among women.  Early detection of breast cancer is the key to reducing the associated mortality rate. The presence of microcalcifications clusters (MCCs is one of the earliest signs of breast cancer. Due to poor imaging contrast of mammograms and noise contamination, radiologists may overlook some diagnostic signs, specially the presence of MCCs. In order to improve cancer detection, image enhancement methods are often used to aid radiologists. In this paper, a new enhancement method was presented for the accurate and early detection of MCCs in mammograms. Materials and Methods The proposed system consisted of four main steps including: 1 image scaling;2 breast region segmentation;3 noise cancellation using a filter, which is sensitive to MCCs; and 4 contrast enhancement of mammograms using Contrast-Limited Adaptive Histogram Equalization (CLAHE and wavelet transform. To evaluate this method, 120 clinical mammograms were used. Results To evaluate the performance of the image enhancement algorithm, contrast improvement index (CII was used. The proposed enhancement method in this research achieved the highest CII in comparison with other methods applied in this study. The Validity of the results was confirmed by an expert radiologist through visual inspection. Conclusion Detection of MCCs significantly improved in contrast-enhanced mammograms. The proposed method could be helpful for radiologists to easily detect MCCs; it could also decrease the number of biopsies and reduce the frequency of clinical misdiagnosis. Moreover, it could be useful prior to segmentation or classification stages.

  14. Adaptive radiotherapy based on contrast enhanced cone beam CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Soevik, Aaste; Skogmo, Hege K. (Dept. of Companion Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo (Norway)), E-mail: aste.sovik@nvh.no; Roedal, Jan (Dept. of Companion Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo (Norway)); Lervaag, Christoffer; Eilertsen, Karsten; Malinen, Eirik (Dept. of Medical Physics, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway))

    2010-10-15

    Cone beam CT (CBCT) imaging has become an integral part of radiation therapy, with images typically used for offline or online patient setup corrections based on bony anatomy co-registration. Ideally, the co-registration should be based on tumor localization. However, soft tissue contrast in CBCT images may be limited. In the present work, contrast enhanced CBCT (CECBCT) images were used for tumor visualization and treatment adaptation. Material and methods. A spontaneous canine maxillary tumor was subjected to repeated cone beam CT imaging during fractionated radiotherapy (10 fractions in total). At five of the treatment fractions, CECBCT images, employing an iodinated contrast agent, were acquired, as well as pre-contrast CBCT images. The tumor was clearly visible in post-contrast minus pre-contrast subtraction images, and these contrast images were used to delineate gross tumor volumes. IMRT dose plans were subsequently generated. Four different strategies were explored: 1) fully adapted planning based on each CECBCT image series, 2) planning based on images acquired at the first treatment fraction and patient repositioning following bony anatomy co-registration, 3) as for 2), but with patient repositioning based on co-registering contrast images, and 4) a strategy with no patient repositioning or treatment adaptation. The equivalent uniform dose (EUD) and tumor control probability (TCP) calculations to estimate treatment outcome for each strategy. Results. Similar translation vectors were found when bony anatomy and contrast enhancement co-registration were compared. Strategy 1 gave EUDs closest to the prescription dose and the highest TCP. Strategies 2 and 3 gave EUDs and TCPs close to that of strategy 1, with strategy 3 being slightly better than strategy 2. Even greater benefits from strategies 1 and 3 are expected with increasing tumor movement or deformation during treatment. The non-adaptive strategy 4 was clearly inferior to all three adaptive strategies

  15. Adaptive radiotherapy based on contrast enhanced cone beam CT imaging

    International Nuclear Information System (INIS)

    Soevik, Aaste; Skogmo, Hege K.; Roedal, Jan; Lervaag, Christoffer; Eilertsen, Karsten; Malinen, Eirik

    2010-01-01

    Cone beam CT (CBCT) imaging has become an integral part of radiation therapy, with images typically used for offline or online patient setup corrections based on bony anatomy co-registration. Ideally, the co-registration should be based on tumor localization. However, soft tissue contrast in CBCT images may be limited. In the present work, contrast enhanced CBCT (CECBCT) images were used for tumor visualization and treatment adaptation. Material and methods. A spontaneous canine maxillary tumor was subjected to repeated cone beam CT imaging during fractionated radiotherapy (10 fractions in total). At five of the treatment fractions, CECBCT images, employing an iodinated contrast agent, were acquired, as well as pre-contrast CBCT images. The tumor was clearly visible in post-contrast minus pre-contrast subtraction images, and these contrast images were used to delineate gross tumor volumes. IMRT dose plans were subsequently generated. Four different strategies were explored: 1) fully adapted planning based on each CECBCT image series, 2) planning based on images acquired at the first treatment fraction and patient repositioning following bony anatomy co-registration, 3) as for 2), but with patient repositioning based on co-registering contrast images, and 4) a strategy with no patient repositioning or treatment adaptation. The equivalent uniform dose (EUD) and tumor control probability (TCP) calculations to estimate treatment outcome for each strategy. Results. Similar translation vectors were found when bony anatomy and contrast enhancement co-registration were compared. Strategy 1 gave EUDs closest to the prescription dose and the highest TCP. Strategies 2 and 3 gave EUDs and TCPs close to that of strategy 1, with strategy 3 being slightly better than strategy 2. Even greater benefits from strategies 1 and 3 are expected with increasing tumor movement or deformation during treatment. The non-adaptive strategy 4 was clearly inferior to all three adaptive strategies

  16. Indeterminate solid hepatic lesions identified on non-diagnostic contrast-enhanced computed tomography: Assessment of the additional diagnostic value of contrast-enhanced ultrasound in the non-cirrhotic liver

    International Nuclear Information System (INIS)

    Quaia, Emilio; De Paoli, Luca; Angileri, Roberta; Cabibbo, Biagio; Cova, Maria Assunta

    2014-01-01

    Objective: To assess the additional diagnostic value of contrast-enhanced ultrasound (CEUS) in the characterization of indeterminate solid hepatic lesions identified on non-diagnostic contrast-enhanced computed tomography (CT). Methods: Fifty-five solid hepatic lesions (1–4 cm in diameter) in 46 non-cirrhotic patients (26 female, 20 male; age ± SD, 55 ± 10 years) underwent CEUS after being detected on contrast-enhanced CT which was considered as non-diagnostic after on-site analysis. Two blinded independent readers assessed CT and CEUS scans and were asked to classify retrospectively each lesion as a malignant or benign based on reference diagnostic criteria for the different hepatic lesion histotypes. Diagnostic accuracy and confidence (area – A z – under ROC curve) were assessed by using gadobenate dimeglumine-enhanced magnetic resonance (MR) imaging (n = 30 lesions), histology (n = 7 lesions), or US follow-up (n = 18 lesions) as the reference standards. Results: Final diagnoses included 29 hemangiomas, 3 focal nodular hyperplasias, 1 hepatocellular adenoma, and 22 metastases. The additional review of CEUS after CT images improved significantly (P < .05) the diagnostic accuracy (before vs after CEUS review = 49% [20/55] vs 89% [49/55] – reader 1 and 43% [24/55] vs 92% [51/55] – reader 2) and confidence (A z , 95% Confidence Intervals before vs after CEUS review = .773 [.652–.895] vs .997 [.987–1] – reader 1 and .831 [.724–.938] vs .998 [.992–1] – reader 2). Conclusions: CEUS improved the characterization of indeterminate solid hepatic lesions identified on non-diagnostic contrast-enhanced CT by identifying some specific contrast enhancement patterns.

  17. Real time contrast enhanced ultrasonography in detection of liver metastases from gastrointestinal cancer.

    Science.gov (United States)

    Piscaglia, Fabio; Corradi, Francesco; Mancini, Mikaela; Giangregorio, Francesco; Tamberi, Stefano; Ugolini, Giampaolo; Cola, Bruno; Bazzocchi, Alberto; Righini, Roberto; Pini, Patrizia; Fornari, Fabio; Bolondi, Luigi

    2007-09-03

    Contrast enhanced ultrasound (CEUS) is an imaging technique which appeared on the market around the year 2000 and proposed for the detection of liver metastases in gastrointestinal cancer patients, a setting in which accurate staging plays a significant role in the choice of treatment. A total of 109 patients with colorectal (n = 92) or gastric cancer prospectively underwent computed tomography (CT) scan and conventional US evaluation followed by real time CEUS. A diagnosis of metastases was made by CT or, for lesions not visible at CT, the diagnosis was achieved by histopathology or by a malignant behavior during follow-up. Of 109 patients, 65 were found to have metastases at presentation. CEUS improved sensitivity in metastatic livers from 76.9% of patients (US) to 95.4% (p cancer. Findings at CEUS and CT appear to be complementary in achieving maximum sensitivity.

  18. Quantitative measurement of contrast enhancement of esophageal squamous cell carcinoma on clinical MDCT.

    Science.gov (United States)

    Li, Rui; Chen, Tian-Wu; Wang, Li-Ying; Zhou, Li; Li, Hang; Chen, Xiao-Li; Li, Chun-Ping; Zhang, Xiao-Ming; Xiao, Ru-Hui

    2012-04-28

    To investigate contrast-enhanced computed tomography (CECT) for discriminating esophageal squamous cell carcinoma (ESCC) from normal esophagus and evaluating outcomes within tumors after chemoradiotherapy (CRT). Sixty-four patients with surgical ESCC served as group A, and underwent thoracic contrast-enhanced scan with 16-section multidetector row CT 1 wk before surgery. Thirty-five patients with advanced ESCC receiving 4-wk CRT and showing response to CRT served as group B, and underwent CT scans similar with group A 4 wk after completion of CRT. In group A, differences in CT attenuation values (in HU) between the preoperative ESCC and background normal esophageal wall (delta CT(1)), or between different background normal esophageal walls (delta CT(2)) were compared. Furthermore, delta CT(1) between group A and B was also compared. In group A, mean delta CT(1) was higher than delta CT(2) (23.86 ± 10.59 HU vs 6.24 ± 3.06 HU, P < 0.05). When a delta CT(1) of 10.025 HU was employed at a cut-off value to discriminate ESCC from normal esophagus, a sensitivity of 89.1% and specificity of 90.6% were achieved. Mean delta CT(1) was lower in group B than in group A (9.25 ± 10.86 vs 23.86 ± 10.59, P < 0.05), and a delta CT(1) of 15.45 HU was obtained at a cut-off value to assess the CRT changes with a sensitivity of 76.6% and specificity of 77.1%. CECT might be a clinical technique for discriminating ESCC from normal esophagus, and evaluating outcome in the tumors treated with CRT.

  19. Contrast-enhanced fluorodeoxyglucose positron emission tomography/contrast-enhanced computed tomography in mediastinal T-cell lymphoma with superior vena cava syndrome

    International Nuclear Information System (INIS)

    Santhosh, Sampath; Gorla, Arun Kumar Reddy; Bhattacharya, Anish; Varma, Subhash Chander; Mittal, Bhagwant Rai

    2016-01-01

    Positron emission tomography-computed tomography (PET/CT) is a routine investigation for the staging of lymphomas. Contrast-enhanced computed tomography is mandatory whenever parenchymal lesions, especially in the liver and spleen are suspected. We report a rare case of primary mediastinal T-cell lymphoma evaluated with contrast-enhanced PET/CT that showed features of superior vena cava syndrome

  20. Comparison of contrast-enhanced ultrasonography with grey-scale ultrasonography and contrast-enhanced computed tomography in diagnosing focal fatty liver infiltrations and focal fatty sparing.

    Science.gov (United States)

    Janica, J; Ustymowicz, A; Lukasiewicz, A; Panasiuk, A; Niemcunowicz-Janica, A; Turecka-Kulesza, E; Lebkowska, U

    2013-01-01

    Fatty liver infiltrations and fatty sparing impair diagnostic performance of grey-scale ultrasonography in differentiating malignant and benign focal liver lesions. In the study, we present our experience in diagnosing focal fatty liver infiltrations and focal fatty sparing with contrastenhanced ultrasonography (CEUS) in comparison to grey-scale ultrasonography and contrast-enhanced computed tomography (CECT). The retrospective study group (n=82 patients), included 44 (53.7%) men, 38 (46.3%) women (aged 29- 81 years, mean 55.8 years) with 48 focal fatty liver infiltrations and 34 focal fatty sparing. All patients underwent grey-scale ultrasonography (US), CEUS using SonoVue® and CECT executed within the 7 days. With US, CEUS and CECT focal fatty liver infiltrations were diagnosed in 22, 46 and 44 cases, respectively. The following values were obtained: sensitivity - 45.8%, 95.8% and 91.7%, specificity - 100% for all, accuracy - 95.2%, 99.6% and 99.3%, respectively. Focal fatty sparing was diagnosed in 16, 31 and 30 cases, respectively. The following values were obtained: sensitivity - 47.1%, 91.2% and 88.2%, specificity - 99.8%, 100% and 100%, accuracy - 95.6%, 99.4% and 99.3%, respectively. No statistically significant differences were found in sensitivity of diagnosing focal fatty liver infiltrations and focal fatty liver sparing between CEUS and CECT. Sensitivity of grey-scale ultrasonography was significantly lower when compared to those of CEUS and CECT (pliver infiltrations.

  1. Development of contrast-enhanced rodent imaging using functional CT

    Science.gov (United States)

    Liang, Yun; Stantz, Keith M.; Krishnamurthi, Ganapathy; Steinmetz, Rosemary; Hutchins, Gary D.

    2003-05-01

    Micro-computed tomography (microCT) is capable of obtaining high-resolution images of skeletal tissues. However its image contrast among soft tissues remains inadequate for tumor detection. High speed functional computed tomography will be needed to image tumors by employing x-ray contrast medium. The functional microCT development will not only facilitate the image contrast enhancement among different tissues but also provide information of tumor physiology. To demonstrate the feasibility of functional CT in mouse imaging, sequential computed tomography is performed in mice after contrast material administration using a high-speed clinical CT scanner. Although the resolution of the clinical scanner is not sufficient to dissolve the anatomic details of rodents, bulky physiological parameters in major organs such as liver, kidney, pancreas, and ovaries (testicular) can be examined. For data analysis, a two-compartmental model is employed and implemented to characterize the tissue physiological parameters (regional blood flow, capillary permeability, and relative compartment volumes.) The measured contrast dynamics in kidneys are fitted with the compartmental model to derive the kidney tissue physiology. The study result suggests that it is feasible to extract mouse tissue physiology using functional CT imaging technology.

  2. A contrast enhancement technique for low light images

    Science.gov (United States)

    Singh, Ankita; Gupta, K. K.

    2016-03-01

    Digital Imagery systems are traditionally bad in low light conditions. In this paper, a new algorithm for contrast improvement is proposed. The algorithm consists of two stages. The first stage is decomposing the input image into four subbands by applying two-dimensional discrete wavelet transform and estimates the singular value matrix of sub band image. The second stage is that it reconstructs the enhanced image by applying the inverse DWT. The technique is compared with conventional image equalization technique such as standard General Histogram Equalization (GHE) and other state-of-the-art techniques such as Quadrant Dynamic Histogram Equalization (QDHE), Singular-Value-Wavelet based image Equalization (SVWE) and Singular Value Equalization (SVE) on the basis of their Peak Signal to Noise Ratio (PSNR) and Root Mean Square Error (RMSE) values. The simulation results indicated that the image contrast enhanced by the purposed method was higher than that of the images enhanced by the other conventional state-of-the-art techniques.

  3. Contrast-enhanced intraoperative ultrasonography in surgery for liver tumors

    Energy Technology Data Exchange (ETDEWEB)

    Torzilli, Guido E-mail: guido.torzilli@fastwebnet.it

    2004-06-01

    IOUS is the most accurate diagnostic technique for assessing focal liver lesions, but still has some drawbacks. Contrast-enhanced ultrasound examination done intraoperatively (CE-IOUS), using second generation contrast agents (SonoVue{sup [reg]}, Bracco-Imaging, Milan, Italy), seems able to overcome those aforementioned lacking aspects of IOUS. In cirrhotic patients with hepatocellular carcinoma (HCC), CE-IOUS provides information about tumor vascularity which are useful for nodules differentiation: this should improve the surgical radicality. Furthermore, two different pattern of enhancement are also recognizable at CE-IOUS in those HCC nodules depicted preoperatively: one of them has no similarity with that observed at computed tomography (CT). In patients who undergo surgery for colorectal liver metastases, CE-IOUS seems to improve the sensitivity of IOUS to small, hypoechoic lesions, reducing the risk to down-stage the disease and enhancing the rate of treatment with curative intent. In conclusion, IOUS accuracy is improved by CE-IOUS with an impact on surgical strategy either for primary than for metastatic tumors. Furthermore, a wider experience with vascular enhancement patterns at CE-IOUS could provide new classification for liver lesions.

  4. The radial scar in contrast-enhanced MR mammography

    International Nuclear Information System (INIS)

    Baum, F.; Fischer, U.; Fuezesi, L.; Obenauer, S.; Vosshenrich, R.; Grabbe, E.

    2000-01-01

    Introduction: In patients with the mammographic findings of a radial scar, contrast enhanced (CE) MR mammography was evaluated in a retrospective study. Material and methods: In 24 women with radial opacities and black star configurations, CE MR mammography was performed. Examinations were done on a 1.5 T system using bilateral superficial coil (2D technique, T 1 -weighted FLASH-sequence, T R 336 ms, T E 5 ms, FA 90 ). Findings in mammography and MR mammography were compared with the histological results. Results: 15 radial scars (including 4 with additional ADH) and 9 carcinomas (6 in co-existence with a radial scar) presenting with a diameter of 3 mm to 13 mm were evaluated. There was no evidence of malignancy in MRI in 12 to 15 radial scars. In MR mammography 6 of the carcinomas fulfilled the criteria for malignant tumors. There were 3 borderline cases (scored 3 points) corresponding histologically to 1 radial scar, and to 2 false positives and 1 false negative. Conclusion: CE MR mammography is superior to other imaging modalities in the differentiation between radial scars and carcinomas. However, lesions suggestive of radial scars have to be removed surgically. (orig.) [de

  5. Cumulative phase delay imaging for contrast-enhanced ultrasound tomography

    International Nuclear Information System (INIS)

    Demi, Libertario; Van Sloun, Ruud J G; Wijkstra, Hessel; Mischi, Massimo

    2015-01-01

    Standard dynamic-contrast enhanced ultrasound (DCE-US) imaging detects and estimates ultrasound-contrast-agent (UCA) concentration based on the amplitude of the nonlinear (harmonic) components generated during ultrasound (US) propagation through UCAs. However, harmonic components generation is not specific to UCAs, as it also occurs for US propagating through tissue. Moreover, nonlinear artifacts affect standard DCE-US imaging, causing contrast to tissue ratio reduction, and resulting in possible misclassification of tissue and misinterpretation of UCA concentration. Furthermore, no contrast-specific modality exists for DCE-US tomography; in particular speed-of-sound changes due to UCAs are well within those caused by different tissue types. Recently, a new marker for UCAs has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental component is in fact observable for US propagating through UCAs, and is absent in tissue. In this paper, tomographic US images based on CPD are for the first time presented and compared to speed-of-sound US tomography. Results show the applicability of this marker for contrast specific US imaging, with cumulative phase delay imaging (CPDI) showing superior capabilities in detecting and localizing UCA, as compared to speed-of-sound US tomography. Cavities (filled with UCA) which were down to 1 mm in diameter were clearly detectable. Moreover, CPDI is free of the above mentioned nonlinear artifacts. These results open important possibilities to DCE-US tomography, with potential applications to breast imaging for cancer localization. (fast track communication)

  6. Assessing Tumor Angiogenesis with Dynamic Contrast Enhanced Magnetic Resonance Imaging

    Science.gov (United States)

    Esparza-Coss, Emilio; Jackson, Edward F.

    2006-09-01

    Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) is a method able of assessing microvascular changes at high spatial resolution and without ionizing radiation. The microcirculation and structure of tumors are fundamentally chaotic in that tumor-derived factors stimulate the endothelial cells to form new small vessels (angiogenesis) and this vasculature deviates markedly from normal hierarchical branching patterns. The tumor-induced microvascular changes lead to blood flow that is both spatially and temporally more heterogeneous than the efficient and uniform perfusion of normal organs and tissues. DCE-MRI allows for the assessment of perfusion and permeability of the tumor microvasculature, including the network of vessels with diameters less than 100 μm, which are beyond the resolution of conventional angiograms. The microvessel permeability to small molecular weight contrast media as well as measures of tumor response can be assessed with different analysis techniques ranging from simple measures of enhancement to pharmacokinetic models. In this work, such DCE-MRI analysis techniques are discussed.

  7. Image fusion for dynamic contrast enhanced magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Leach Martin O

    2004-10-01

    Full Text Available Abstract Background Multivariate imaging techniques such as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI have been shown to provide valuable information for medical diagnosis. Even though these techniques provide new information, integrating and evaluating the much wider range of information is a challenging task for the human observer. This task may be assisted with the use of image fusion algorithms. Methods In this paper, image fusion based on Kernel Principal Component Analysis (KPCA is proposed for the first time. It is demonstrated that a priori knowledge about the data domain can be easily incorporated into the parametrisation of the KPCA, leading to task-oriented visualisations of the multivariate data. The results of the fusion process are compared with those of the well-known and established standard linear Principal Component Analysis (PCA by means of temporal sequences of 3D MRI volumes from six patients who took part in a breast cancer screening study. Results The PCA and KPCA algorithms are able to integrate information from a sequence of MRI volumes into informative gray value or colour images. By incorporating a priori knowledge, the fusion process can be automated and optimised in order to visualise suspicious lesions with high contrast to normal tissue. Conclusion Our machine learning based image fusion approach maps the full signal space of a temporal DCE-MRI sequence to a single meaningful visualisation with good tissue/lesion contrast and thus supports the radiologist during manual image evaluation.

  8. Intraoperative Contrast Enhanced Ultrasound Evaluates the Grade of Glioma

    Directory of Open Access Journals (Sweden)

    Ling-Gang Cheng

    2016-01-01

    Full Text Available Objective. The aim of our study was to investigate the value of intraoperative contrast enhanced ultrasound (CEUS for evaluating the grade of glioma and the correlation between microvessel density (MVD and vascular endothelial growth factor (VEGF. Methods. We performed intraoperative conventional ultrasound (CUS and CEUS on 88 patients with gliomas. All of the patients have undergone surgery and obtained the results of pathology. All patients have undergone intraoperative CUS and CEUS to compare the characteristics of different grade gliomas and the results of CUS and CEUS were compared with pathological results. Results. The time to start (TTS and time to peak (TTP of low grade glioma (LGG were similar to those of edema and normal brain surrounding glioma. The enhanced extent of LGG was higher than that of the normal brain and edema. The TTS and TTP of high grade glioma were earlier than those of the edema and normal brain surrounding glioma. The enhancement of HGG was higher than that of LGG. The absolute peak intensity (API was correlated with MVD and VEGF. Conclusion. Intraoperative CEUS could help in determining boundary of peritumoral brain edema of glioma. Intraoperative CEUS parameters in cerebral gliomas could indirectly reflect the information of MVD and VEGF.

  9. Parallel implementation of the adaptive neighborhood contrast enhancement technique

    Science.gov (United States)

    Alto, Hilary; Gavrilov, Dmitri; Rangayyan, Rangaraj M.

    1999-10-01

    An adaptive neighborhood contrast enhancement (ANCE) technique was developed to improve the perceptibility of features in digitized mammographic images for use in breast cancer screening. The computationally intensive algorithm was implemented on a cluster of 30 DEC Alpha processors using the message passing interface. The parallel implementation of the ANCE technique utilizes histogram- based image partitioning with each partition consisting of pixels of the same gray-level value regardless of their location in the image. The master processor allots one set of pixels to each slave processor. The slave returns the results to the master, and the master than sends a new set of pixels to the slave for processing. This procedure continues until there are no sets of pixels left. The subdivision of the original image based on gray-level values guarantees that slave processors do not process the same pixel, and is specifically well-suited to the characteristics of the ANCE algorithm. The parallelism value of the problem is approximately 16, i.e., the performance does not improve significantly when more than 16 processors are used. The result is a substantial improvement in processing time, leading to the enhancement of 4 K X 4 K pixel images in the range of 20 to 60 seconds.

  10. Dynamic Contrast-Enhanced CT in Patients with Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Rie Ø. Eriksen

    2016-09-01

    Full Text Available The aim of this systematic review is to provide an overview of the use of Dynamic Contrast-enhanced Computed Tomography (DCE-CT in patients with pancreatic cancer. This study was composed according to the PRISMA guidelines 2009. The literature search was conducted in PubMed, Cochrane Library, EMBASE, and Web of Science databases to identify all relevant publications. The QUADAS-2 tool was implemented to assess the risk of bias and applicability concerns of each included study. The initial literature search yielded 483 publications. Thirteen articles were included. Articles were categorized into three groups: nine articles concerning primary diagnosis or staging, one article about tumor response to treatment, and three articles regarding scan techniques. In exocrine pancreatic tumors, measurements of blood flow in eight studies and blood volume in seven studies were significantly lower in tumor tissue, compared with measurements in pancreatic tissue outside of tumor, or normal pancreatic tissue in control groups of healthy volunteers. The studies were heterogeneous in the number of patients enrolled and scan protocols. Perfusion parameters measured and analyzed by DCE-CT might be useful in the investigation of characteristic vascular patterns of exocrine pancreatic tumors. Further clinical studies are desired for investigating the potential of DCE-CT in pancreatic tumors.

  11. Radiochromic film dosimetry of contrast-enhanced radiotherapy (CERT)

    International Nuclear Information System (INIS)

    Morris, Kevin N; Weil, Michael D; Malzbender, Rainer

    2006-01-01

    Contrast-enhanced radiotherapy (CERT) employs elevated concentrations of high-Z contrast media in targets to dramatically increase the absorbed dose of radiation relative to the surrounding tissues. However, it is difficult to measure the dose enhancement with routine clinical instruments because the photoelectrons and Auger electrons produced by the interaction of kilovoltage x-rays with the contrast agent travel extremely short distances. We have developed a technique utilizing unlaminated radiochromic film to measure the maximum dose enhancement factor attainable in solutions of contrast agent with iodine concentrations ranging from 0% to 37% (w/v). The films were also used to simultaneously measure the dose enhancement and beam attenuation through solutions containing 0%, 5% and 10% iodine (w/v). These depth-dose measurements were made in phantoms representing 3 cm targets located 0 and 4.8 cm deep in acrylic. Higher concentrations of contrast yielded greater dose enhancement and target-to-surface dose ratios, but caused more rapid attenuation of the beam as it traversed the target. The dose distribution across the entire target could be improved by employing multiple beams. These results, using concentrations of contrast that are clinically achievable by intratumoural injection, illustrate the potential of CERT for the specific delivery of high doses of radiation to targets at depth

  12. Early and Delayed Myocardial Enhancement in Myocardial Infarction Using Two-Phase Contrast-Enhanced Multidetector-Row CT

    International Nuclear Information System (INIS)

    Ko, Sung-Min; Kim, Young-Whan; Han, Seong-Wook; Seo, Joon-Beom

    2007-01-01

    The purpose of this study was to describe the myocardial enhancement patterns in patients with myocardial infarction using two-phase contrast enhanced multidetector-row computed tomography (MDCT). Twenty-three patients with clinically proven myocardial infarction (17 acute myocardial infarction [AMI] and 6 chronic myocardial infarction [CMI]) were examined with two-phase contrast-enhanced ECG-gated MDCT. The presence, location, and patterns of myocardial enhancement on two phase MDCT images were compared with infarcted myocardial territories determined by using electrocardiogram, echocardiography, thallium-201 single photon emission computed tomography, catheter and MDCT coronary angiography. After clinical assessment, the presence of myocardial infarctions were found in 27 territories (19 AMI and 8 CMI) of 23 patients. Early perfusion defects were observed in 30 territories of all 23 patients. Three territories not corresponding to a myocardial infarction were detected in three patients with AMI and were associated with artifacts. Fourteen of perfusion defects were in the left anterior descending artery territory, four in the left circumflex artery territory, and nine in the right coronary artery territory. Delayed enhancement was observed in 25 territories (17 AMI and 8 CMI) of 21 patients. Delayed enhancement patterns were variable. Transmural early perfusion defects (n =12) were closely associated with transmural late enhancement (n = 5) and subendocardial residual defect with subepicardial late enhancement (n = 5). Myocardial infarction showed early perfusion defects and variable delayed enhancement patterns on two-phase contrast-enhanced MDCT. Delayed enhancement technique of MDCT could provide additional information of the location and extent of infarcted myocardium, and could be useful to plan appropriate therapeutic strategies in patients with AMI

  13. Prevalence Study of Proximal Vertebral Artery Stenosis Using High-Resolution Contrast-Enhanced Magnetic Resonance Angiography

    International Nuclear Information System (INIS)

    Kim, S.H.; Lee, J.S.; Kwon, O.K.; Han, M.K.; Kim, J.H.

    2005-01-01

    Purpose: To evaluate the prevalence of proximal vertebral artery stenosis, compared with those of the distal vertebral/basilar artery and extracranial internal carotid artery, in a large population of stroke and non-stroke patients. Material and Methods: Nine-hundred-and-thirty-five patients who underwent high-resolution contrast-enhanced magnetic resonance angiography in a regional general hospital were categorized into six groups based on neurological symptoms and disease: an asymptomatic group (n ∼ 182), a minor symptom group with headache or dizziness (n ∼ 519), a cardiac group with coronary artery steno-occlusive disease (n ∼ 15), a hemorrhagic group with old cerebral hemorrhage (n ∼ 26), an anterior circulation infarct group (n ∼ 121), and posterior circulation infarct group (n ∼ 72). Prevalence of stenosis of the proximal vertebral artery, distal vertebral/basilar artery, and internal carotid artery was analyzed. Results: The prevalence of stenosis of the proximal vertebral artery, distal vertebral/basilar artery, and internal carotid artery was 12.9%, 5.5%, and 7.2%, respectively, in the study population, and rose as the age increased (P <0.0001 for all arteries). The prevalence of stenosis of the proximal vertebral artery, distal vertebral/basilar artery, and internal carotid artery was 3.3%, 0.5%, and.1%, respectively, in the asymptomatic group; 8.3%, 2.1%, and 3.7%, respectively, in the minor symptom group; 13.3%, 6.7%, and 6.7%, respectively, in the cardiac group; 19.2%, 7.7%, and 7.7%, respectively, in the hemorrhagic group; 27.3%, 8.3%, and 25.6%, respectively, in the anterior circulation infarct group; and 44.4%, 36.1%, and 16.7%, respectively, in the posterior circulation infarct group. This increasing tendency of stenosis accordingly was statistically significant ( P <0.0001 for all arteries). Conclusion: The prevalence of proximal vertebral artery stenosis was highest, compared with those of the distal vertebral/basilar artery and

  14. Association of aortic wall thickness on contrast-enhanced chest CT with major cerebro-cardiac events.

    Science.gov (United States)

    Tresoldi, Silvia; Di Leo, Giovanni; Zoffoli, Elena; Munari, Alice; Primolevo, Alessandra; Cornalba, Gianpaolo; Sardanelli, Francesco

    2014-11-01

    There is a significant association between aortic atherosclerosis and previous major cardiovascular events. Particularly, thoracic aortic atherosclerosis is closely related to the degree of coronary and carotid artery disease. Thus, there is a rationale for screening the thoracic aorta in patients who undergo a chest computed tomography (CT) for any clinical question, in order to detect patients at increased risk of cerebro-cardiovascular (CCV) events. To estimate the association between either thoracic aortic wall thickness (AWT) or aortic total calcium score (ATCS) and CCV events. One hundred and forty-eight non-cardiac patients (78 men; 67 ± 12 years) underwent chest contrast-enhanced multidetector CT (MDCT). The AWT was measured at the level of the left atrium (AWTref) and at the maximum AWT (AWTmax). Correlation with clinical CCV patients' history was estimated. The value of AWTmax and of a semi-quantitative ATCS as a marker for CCV events was assessed using receiver-operating characteristic curve (ROC) analysis and multivariate regression analysis. Out of 148 patients, 59% reported sedentary lifestyle, 44% hypertension, 32% smoking, 23% hypercholesterolemia, 13% family history of cardiac disease, 12% diabetes, and 10% BMI ≥ 30 kg/m(2); 9% reported myocardial infarction, 8% aortic aneurism, 8% myocardial revascularization, and 2% ischemic stroke. Twenty-six percent of patients had a medium-to-high ATCS. Both AWTmax and AWTref correlated with hypertension and age (P < 0.002). At the ROC analysis, a 4.8 mm threshold was associated to a 90% specificity and an odds ratio of 6.3 (AUC = 0.735). Assuming as threshold the AWTmax median value (4.3 mm) of patients who suffered from at least one CCV event in their history, a negative predictive value of 90%, a RR of 3.6 and an OR of 6.3 were found. At the multivariate regression analysis, AWTmax was the only independent variable associated to the frequency of CCV events. Patients with increased thoracic

  15. Performance of integrated FDG-PET/contrast-enhanced CT in the staging and restaging of colorectal cancer: Comparison with PET and enhanced CT

    International Nuclear Information System (INIS)

    Dirisamer, Albert; Halpern, Benjamin S.; Floery, Daniel; Wolf, Florian; Beheshti, Mohsen; Mayerhoefer, Marius E.; Langsteger, Werner

    2010-01-01

    Objective: The purpose of this study was to assess the diagnostic value of PET/CT as a one step examination in patients with colorectal cancer. Therefore we proved whether diagnostic PET/CT adds information over PET or contrast-enhanced CT alone for staging or restaging of patients with colorectal cancer. Methods: Seventy-three patients (46 males and 27 females; age range: 50-81 years; mean age: 67 years) with known colorectal cancer underwent 18F-FDG-PET/CT for staging or restaging. Results: Of the 73 patients 26 patients underwent PET/CT for staging and 47 for restaging. 266 metastases could be detected in 60 patients. Contrast-enhanced PET/CT had a lesion-based sensitivity of 100%, contrast-enhanced CT of 91% and PET of 85%. PET/CT identified 2 lesions as false positive. PET/CT could also reach a patient-based sensitivity of 100%, which was superior to contrast-enhanced CT and PET. Conclusion: Our study clearly demonstrated the added value of contrast-enhanced PET/CT in staging and restaging patients with colorectal cancer over CT and PET alone.

  16. Cumulative phase delay imaging - A new contrast enhanced ultrasound modality

    Energy Technology Data Exchange (ETDEWEB)

    Demi, Libertario, E-mail: l.demi@tue.nl; Sloun, Ruud J. G. van; Mischi, Massimo [Lab. of Biomedical Diagnostics, Dept. of Electrical Eng., Eindhoven University of Technology (Netherlands); Wijkstra, Hessel [Lab. of Biomedical Diagnostics, Dept. of Electrical Eng., Eindhoven University of Technology (Netherlands); Academic Medical Center, Urology Dept., University of Amsterdam (Netherlands)

    2015-10-28

    Recently, a new acoustic marker for ultrasound contrast agents (UCAs) has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental pressure wave field components is in fact observable for ultrasound propagating through UCAs. This phenomenon is absent in the case of tissue nonlinearity and is dependent on insonating pressure and frequency, UCA concentration, and propagation path length through UCAs. In this paper, ultrasound images based on this marker are presented. The ULA-OP research platform, in combination with a LA332 linear array probe (Esaote, Firenze Italy), were used to image a gelatin phantom containing a PVC plate (used as a reflector) and a cylindrical cavity measuring 7 mm in diameter (placed in between the observation point and the PVC plate). The cavity contained a 240 µL/L SonoVueO{sup ®} UCA concentration. Two insonating frequencies (3 MHz and 2.5 MHz) were used to scan the gelatine phantom. A mechanical index MI = 0.07, measured in water at the cavity location with a HGL-0400 hydrophone (Onda, Sunnyvale, CA), was utilized. Processing the ultrasound signals backscattered from the plate, ultrasound images were generated in a tomographic fashion using the filtered back-projection method. As already observed in previous studies, significantly higher CPD values are measured when imaging at a frequency of 2.5 MHz, as compared to imaging at 3 MHz. In conclusion, these results confirm the applicability of the discussed CPD as a marker for contrast imaging. Comparison with standard contrast-enhanced ultrasound imaging modalities will be the focus of future work.

  17. The forgotten organ: Contrast enhanced sonography of the spleen

    Energy Technology Data Exchange (ETDEWEB)

    Goerg, Christian [Medizinische Universitaetsklinik, Baldingerstrasse, 35043 Marburg/Lahn (Germany)], E-mail: goergc@med.uni-marburg.de

    2007-11-15

    Objective: Ultrasound contrast agents in conjunction with contrast specific imaging techniques, are increasingly accepted in clinical use for diagnostic imaging in several organs. Contrast enhanced sonography (CES) of second-generation contrast media have shown a spleen-specific uptake of the microbubble contrast agent. The aim of this review is to illustrate indications for the use of CES in patients with suspected (peri-)splenic pathology. Methods: This review based on the experience of transcutaneous CES in 200 patients with (peri-)splenic pathology diagnosed by B-mode sonography at an internal medicine center. CES studies were performed with a contrast-devoted unit (Acuson, Sequoia, Siemens medical solution) that had contrast-specific, continuous-mode software. A low mechanical index was used. A sulfur hexafluoride-based microbubble contrast medium (Sonovue, Bracco SpA, Milan, Italy) was injected. Results: On our experience, there are several clinical conditions which may show an diagnostic advantage of CES in comparison to B-mode US. CES should be performed to investigate: (1) the perisplenic tumor to diagnose or exclude accessory spleen, (2) the small-sized spleen to diagnose functional asplenia/hyposplenia, (3) the inhomogenous spleen of unknown cause to diagnose focal lesions within the spleen, (4) the incidentally found hypoechoic splenic tumor to diagnose high vascular splenic hemangioma, (5) focal lesions suspect for splenic abscess, hematoma, infarction to confirme diagnosis, and (6) patients with abdominal trauma to diagnose or exclude splenic injuriy. Conclusion: CES is of diagnostic value in several clinical circumstances to diagnose accessory spleen, functional asplenia, small-sized splenic involvement, high vascular splenic hemangioma, and vascular splenic pathology like splenic infarction, splenic abscess, and splenic laceration.

  18. TMJ disorders and pain: Assessment by contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Farina, Davide; Bodin, Christiane; Gandolfi, Silvia; De Gasperi, Werner; Borghesi, Andrea; Maroldi, Roberto

    2009-01-01

    Though magnetic resonance (MRI) is a widely accepted standard for the assessment of patients with temporomandibular joint (TMJ) disorders, efforts to correlate symptoms to MRI findings have often given controversial results. Aim of this study was to investigate the correlation between TMJ pain and findings of contrast-enhanced MRI. Thirty-eight consecutive patients with TMJ dysfunction syndrome (study group) were examined with MRI. Protocol included T2 turbo spin-echo sequence, T1 spin-echo sequence, and T2 gradient-echo (acquired with closed jaw, at intermediate and maximal opening). Post-contrast phase was obtained through a fat sat 3D T1 gradient-echo sequence (VIBE). Post-contrast findings in the study group were matched with those obtained in a control group of 33 patients submitted to MRI of the paranasal sinuses. Statistically significant difference was found between condylar medullary bone enhancement in painful TMJ, in painless TMJ and control group. In addition the average thickness of joint soft tissue enhancement in painful TMJ was superior to painless TMJ (p < 0.0001) and to control group. On multivariate logistic regression analysis, the odds ratio that a painful TMJ showed disk displacement, osteoarthrosis, effusion and JST enhancement were 3.05, 3.18, 1.2 and 11.36, respectively. Though not histologically proven, TMJ enhancement could reflect the presence of inflammation in painful joints. Furthermore, the administration of contrast could be of help for the assessment of patients with orofacial pain, particularly when clinical exploration is insufficient to ascribe the pain to TMJ.

  19. TMJ disorders and pain: Assessment by contrast-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Farina, Davide [Department of Radiology (School of Medicine), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy)], E-mail: nappaje@yahoo.it; Bodin, Christiane [Division of Gnathology (School of Dentistry), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy); Gandolfi, Silvia [Department of Radiology (School of Medicine), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy); De Gasperi, Werner [Division of Gnathology (School of Dentistry), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy); Borghesi, Andrea; Maroldi, Roberto [Department of Radiology (School of Medicine), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy)

    2009-04-15

    Though magnetic resonance (MRI) is a widely accepted standard for the assessment of patients with temporomandibular joint (TMJ) disorders, efforts to correlate symptoms to MRI findings have often given controversial results. Aim of this study was to investigate the correlation between TMJ pain and findings of contrast-enhanced MRI. Thirty-eight consecutive patients with TMJ dysfunction syndrome (study group) were examined with MRI. Protocol included T2 turbo spin-echo sequence, T1 spin-echo sequence, and T2 gradient-echo (acquired with closed jaw, at intermediate and maximal opening). Post-contrast phase was obtained through a fat sat 3D T1 gradient-echo sequence (VIBE). Post-contrast findings in the study group were matched with those obtained in a control group of 33 patients submitted to MRI of the paranasal sinuses. Statistically significant difference was found between condylar medullary bone enhancement in painful TMJ, in painless TMJ and control group. In addition the average thickness of joint soft tissue enhancement in painful TMJ was superior to painless TMJ (p < 0.0001) and to control group. On multivariate logistic regression analysis, the odds ratio that a painful TMJ showed disk displacement, osteoarthrosis, effusion and JST enhancement were 3.05, 3.18, 1.2 and 11.36, respectively. Though not histologically proven, TMJ enhancement could reflect the presence of inflammation in painful joints. Furthermore, the administration of contrast could be of help for the assessment of patients with orofacial pain, particularly when clinical exploration is insufficient to ascribe the pain to TMJ.

  20. Differentiation of benign and malignant solitary pulmonary nodules : value of contrast-enhanced dynamic MR imaging

    International Nuclear Information System (INIS)

    Kim, Jeong Ho; Kim, Hyung Jin; Han, Heon; Lee, Hong Lyeol; Kim, Kwang Ho; Suh, Chang Hae

    1999-01-01

    To evaluate the usefulness of contrast-enhanced dynamic MR imaging for differentiation of benign and malignant solitary pulmonary nodules (SPNs). Twenty-three patients with histologically or radiologically provened SPNs smaller than 40mm (14 benign, 9 malignant) underwent MR examination using the breath-hold fast multiplanar spoiled gradient echo (FMPSPGR) technique. Pre-enhancement MR examination was followed by serial scans obtained at one-minute intervals, beginning one-minute after the onset of bolus injection of paramagnetic contrast agent for a total of five scans. Signal intensities of SPNs were measured from pre- and post-contrast enhanced MR images and peak percentage increase in signal intensity (p%SI) was calculated. Mean percentage increase in signal intensity (m%SI) was also calculated and the time-m%SI curve was plotted. The enhancement patterns of SPNs were classified as homogeneous, peripheral rim-like, inhomogeneous, or no (or minimal) enhancement. We compared differences in p%SI, the pattern of the time-m%SI curve, and the pattern of enhancement between benign and malignant SPNs. On dynamic MR images, alignant SPNs (n=9) showed a significantly higher p%SI than benign SPNs (n=14) (malignant : mean 120.6, range 81.8-171.6; benign : mean 29.5, range 3.7-78.9)(p<0.0001). With 80 p%SI as the threshold for malignancy-positive, both sensitivity and specificity were 100%. The m%SI of malignant SPNs rapidly increased at one minute after enhancement and decreased gradually thereafter, whereas that of benign SPNs increased more slowly to form a plateau. Eighty-nine percent (8/9) of malignant SPNs showed homogeneous enhancement. In contrast, among benign SPNs, peripheral rim-like enhancement and no (or minimal) enhancement occurred in the same proportion of cases : 50%(7/14). The superb demonstration of different enhancement characteristics obtained using dynamic contrast-enhanced MR imaging is useful to discriminate malignant from benign SPNs

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  2. Detection of bleeding in patients with major pelvic fractures: value of contrast-enhanced CT.

    Science.gov (United States)

    Cerva, D S; Mirvis, S E; Shanmuganathan, K; Kelly, I M; Pais, S O

    1996-01-01

    We performed a retrospective review of trauma patients who had undergone both pelvic angiography and preangiographic i.v. contrast-enhanced CT to determine whether CT can accurately demonstrate the presence or absence of pelvic bleeding in patients with multisystem trauma and major pelvic fractures. We reviewed the medical records and imaging studies of all patients, identified through a trauma radiology database, who had undergone pelvic angiography and preangiographic contrast-enhanced CT during a 48-month period. Results of CT scans were recorded by consensus interpretation of three radiologists without knowledge of angiographic findings. Sites of contrast material extravasation seen on CT scans were noted and compared with sites of bleeding or vascular injury identified by selective pelvic angiography. Thirty patients with blunt trauma and pelvic fractures underwent both pelvic angiography and preangiographic CT studies. Findings on pelvic angiograms were positive at 26 sites in 19 patients and included contrast agent extravasation at 23 sites and vessel abnormalities without extravasation at three sites. Preangiographic pelvic CT scans showed contrast agent extravasation at 20 sites in 16 patients. Three patients had no contrast agent extravasation demonstrated by CT but had bleeding demonstrated by angiography. CT detected bleeding in 16 of 19 patients who had extravasation or vascular injury demonstrated by angiography, for a sensitivity of 84%. Results of pelvic angiography were negative in 11 patients, and none had evidence of bleeding on preangiographic CT scans. Two sites of contrast agent extravasation identified in two patients by CT did not show bleeding at angiography, for a specificity of 85% for the detection of bleeding. The overall accuracy of CT for determining the presence or absence of bleeding was 90%. Knowledge of sites of ongoing hemorrhage is crucial for optimizing the sequence of diagnostic and therapeutic studies in patients with blunt

  3. Initial staging of Hodgkin's disease: role of contrast-enhanced 18F FDG PET/CT.

    Science.gov (United States)

    Chiaravalloti, Agostino; Danieli, Roberta; Caracciolo, Cristiana Ragano; Travascio, Laura; Cantonetti, Maria; Gallamini, Andrea; Guazzaroni, Manlio; Orlacchio, Antonio; Simonetti, Giovanni; Schillaci, Orazio

    2014-08-01

    The objective of this study was to compare the diagnostic accuracy of positron emission tomography/low-dose computed tomography (PET/ldCT) versus the same technique implemented by contrast-enhanced computed tomography (ceCT) in staging Hodgkin's disease (HD).Forty patients (18 men and 22 women, mean age 30 ± 9.6) with biopsy-proven HD underwent a PET/ldCT study for initial staging including an unenhanced low-dose computed tomography for attenuation correction with positron emission tomography acquisition and a ceCT, performed at the end of the PET/ldCT scan, in the same exam session. A detailed datasheet was generated for illness locations for separate imaging modality comparison and then merged in order to compare the separate imaging method results (PET/ldCT and ceCT) versus merged results positron emission tomography/contrast-enhanced computed tomography (PET/ceCT). The nodal and extranodal lesions detected by each technique were then compared with follow-up data that served as the reference standard.No significant differences were found at staging between PET/ldCT and PET/ceCT in our series. One hundred and eighty four stations of nodal involvement have been found with no differences in both modalities. Extranodal involvement was identified in 26 sites by PET/ldCT and in 28 by PET/ceCT. We did not find significant differences concerning the stage (Ann Arbor).Our study shows a good concordance and conjunction between PET/ldCT and ceCT in both nodal and extranodal sites in the initial staging of HD, suggesting that PET/ldCT could suffice in most of these patients.

  4. Evaluation of breast lesions by contrast enhanced ultrasound: Qualitative and quantitative analysis

    International Nuclear Information System (INIS)

    Wan Caifeng; Du Jing; Fang Hua; Li Fenghua; Wang Lin

    2012-01-01

    Objective: To evaluate and compare the diagnostic performance of qualitative, quantitative and combined analysis for characterization of breast lesions in contrast enhanced ultrasound (CEUS), with histological results used as the reference standard. Methods: Ninety-one patients with 91 breast lesions BI-RADS 3–5 at US or mammography underwent CEUS. All lesions underwent qualitative and quantitative enhancement evaluation. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of different analytical method for discrimination between benign and malignant breast lesions. Results: Histopathologic analysis of the 91 lesions revealed 44 benign and 47 malignant. For qualitative analysis, benign and malignant lesions differ significantly in enhancement patterns (p z1 ), 0.768 (A z2 ) and 0.926(A z3 ) respectively. The values of A z1 and A z3 were significantly higher than that for A z2 (p = 0.024 and p = 0.008, respectively). But there was no significant difference between the values of A z1 and A z3 (p = 0.625). Conclusions: The diagnostic performance of qualitative and combined analysis was significantly higher than that for quantitative analysis. Although quantitative analysis has the potential to differentiate benign from malignant lesions, it has not yet improved the final diagnostic accuracy.

  5. Postoperative lumbar MR imaging with contrast enhancement. Comparison between symptomatic and asymptomatic patients

    Energy Technology Data Exchange (ETDEWEB)

    Grane, P. [Dept. of Neuroradiology, Karolinska Hospital, Stockholm (Sweden); Tullberg, T. [Dept. of Orthopaedics, St. Goeran`s Hospital, Stockholm (Sweden); Rydberg, J. [Dept. of Radiology, St. Goeran`s Hospital, Stockholm (Sweden); Lindgren, L. [Dept. of Neurosurgery, Karolinska Hospital, Stockholm (Sweden)

    1995-05-01

    Contrast-enhanced MR imaging of the spine after surgery for lumbar disk herniation almost always shows pathologic changes. To investigate to what extent these changes are correlated to patients` actual clinical symptoms, we compared the postoperative MR findings in 19 asymptomatic patients with 42 symptomatic patients (43 levels). The asymptomatic patients underwent MR examination one year after surgery. Twenty-six of the symptomatic patients underwent MR one year of less after surgery, and in 16 patients (17 levels) MR was performed more than one year after surgery. Sixteen percent of the asymptomatic and 42% of the symptomatic patients had disk herniation at the level of previous surgery. Most of the herniated disks were found in the symptomatic patients less than one year after surgery. The amount of epidural scar tissue, displacement and thickening of nerve roots, and compression of the dural sac were also studied. Disk herniation as a probable cause of recurrent sciatica was a common finding among symptomatic patients examined one year or less after surgery. In comparing asymptomatic patients and symptomatic patients with more than one year between surgery and MR examination, no significant radiologic differences, including disk herniation, were found. (orig.).

  6. [Comparative diagnostic value of computed tomography and contrast-enhanced ultrasonography in diagnosis of focal liver lesions].

    Science.gov (United States)

    Zviniene, Kristina; Zaboriene, Inga; Basevicius, Algidas; Pundzius, Juozas

    2009-01-01

    OBJECTIVE. The aim of the study was to evaluate focal liver lesions by computed tomography and contrast-enhanced ultrasonography and to compare their diagnostic values. MATERIALS AND METHODS. There were 67 patients, examined and treated in the Departments of Gastroenterology, Surgery, and Oncology, Hospital of Kaunas University of Medicine, during 2007 (study group). All the patients underwent contrast-enhanced ultrasonography and bolus computed tomography. Control group included 73 patients with focal hepatic lesions who were examined and treated in the Hospital of Kaunas University of Medicine during 2006. Focal hepatic lesions were detected and characterized by conventional ultrasonography and bolus computed tomography. The diagnosis was confirmed by biopsy or during surgery in both groups, and hemangiomas were confirmed by magnetic resonance imaging. Patients' age varied from 20 to 80 years (there were 46 [68.7%] women and 21 [31.3%] men with a mean age of 55.85+/-13.417 years). The age of patients in the study group varied from 18 to 91 years (mean age, 60.81+/-16.059 years; out of 73 patients, 46 [63%] were women and 27 [37%] men). RESULTS. The following was determined in the study group: hemangioma (n=18, 26.9%), focal nodular hyperplasia (n=4, 6%), adenoma (n=2, 3%), echinococcosis (n=2, 3%), hepatocellular carcinoma (n=11, 16.4%), cholangiocellular carcinoma (n=1, 1.5%), solitary metastasis (n=13, 19.4%), hepatic cyst (n=3, 4.5%), etc. The sensitivity and specificity of contrast-enhanced ultrasonography as compared with computed tomography in detecting and characterizing focal liver lesions was 44.2% and 46.7%, respectively; positive prognostic value was 74.2% and negative prognostic value was 19.4%. The sensitivity and specificity of conventional ultrasonography as compared with contrast-enhanced ultrasonography in detecting and characterizing focal liver lesions was 34.5% and 100%, respectively; positive prognostic value was 100% and negative prognostic

  7. Serial contrast-enhanced magnetic resonance and magnetization transfer in the study of patients with multiple sclerosis

    International Nuclear Information System (INIS)

    Rovira, A.; Alonso, J.; Cucurella, G.; Nos, C.; Tintore, M.; Pedraza, S.; Rio, J.; Montalban, X.

    1997-01-01

    To demonstrate the changes in the magnetization transfer ratio (MTR) of different demyelinating plaques, correlating them with the baseline values in T1-weighted contrast-enhanced magnetic resonance (MR) sequences in order to relate them more closely to the underlying disease. The study was based on 33 demyelinating plaques obtained from six patients clinically diagnosed as having remitting-recurring multiple sclerosis (MS). All the patients underwent two MR studies at a 3 to 5-month interval, including contrast-enhanced T1 and T2- weighted sequences and magnetization transfer images. The latter were used to calculate the MTR for each of the demyelinating plaques included in the study. The statistical analysis of the results obtained revealed statistically significant between initial MTR values and those of subsequent T1-weighted sequences. The MTR demonstrate significant differences between plaques according to contrast-enhanced T1-weigh tes sequences, probably indicating variable degrees of edema, demyelination and tissue destruction. These differences should be taken into account to enable the use of T1-weighted sequences to quantify the lesion load in MS patients. (Author) 35 refs

  8. Effects of Contrast-Enhanced Ultrasonography in Monitoring Hepatic Microcirculation After Rat Liver Ischemia-Reperfusion Injury.

    Science.gov (United States)

    Zhang, Yun-Fei; Li, Hong; Zhang, Bao-Hui; Fang, Xiu-Bin

    2016-06-01

    Our objective was to evaluate the effects of contrast-enhanced ultrasonography in monitoring microcirculation after rat liver ischemia-reperfusion injury. Male Wistar rats (n = 36) were divided into sham-operated and ischemia-reperfusion groups. Rats in the ischemia-reperfusion groups underwent normothermic liver ischemia for 15 minutes followed by 1, 6, or 24 hours of reperfusion. At different time points, contrast-enhanced ultrasonography was performed to determine peak intensity in monitoring hepatic microcirculation. In addition, serum levels of alanine aminotransferase, aspartate aminotransferase, tumor necrosis factor α, and interleukin 1β levels were measured. Histopathologic changes were also observed. One hour after reperfusion, peak intensity values decreased, and serum levels of alanine aminotransferase, tumor necrosis factor α, and interleukin 1β increased significantly in the ischemia-reperfusion group compared with the sham-operated group. Histology results showed mild injury. Six hours after reperfusion, peak intensity values decreased continuously, serum levels of alanine aminotransferase, tumor necrosis factor α, and interleukin 1β decreased, and aspartate aminotransferase levels increased. Histology results showed severe injury compared with 1 hour after reperfusion. Twenty-four hours after reperfusion, peak intensity values increased, alanine aminotransferase and aspartate aminotransferase levels decreased, and histology results showed moderate injury compared with 6 hours after reperfusion. Peak intensity values were negatively correlated to alanine aminotransferase (P liver ischemia-reperfusion injury can be monitored by contrast-enhanced ultrasonography. The perfusion of contrast agents negatively correlates to the severity of injuries.

  9. Contrast-enhanced computed tomographic colonography in the follow-up of colorectal cancer patients: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Laghi, Andrea; Iannaccone, Riccardo; Carbone, Iacopo; Piacentini, Francesca; Passariello, Roberto [Department of Radiology, University of Rome ' ' La Sapienza' ' , Policlinico Umberto I, Rome (Italy); Bria, Emilio; Trasatti, Luciana; Lauro, Salvatore; Vecchione, Aldo [Department of Medical Oncology, Policlinico S. Andrea (Italy)

    2003-04-01

    The aim of our study was to assess whether contrast-enhanced CT colonography is a feasible alternative to both conventional colonoscopy and liver ultrasonography in the follow-up program of colorectal cancer patients. Thirty-five patients, surgically treated for colorectal cancer, underwent a follow-up program that included physical examination, carcinoembryonic antigen serum assay, conventional colonoscopy, liver ultrasonography, and chest X-ray. For these patients, we added a yearly contrast-enhanced CT colonography. All CT examinations were performed with a high-resolution protocol using a multidetector spiral CT scanner (Siemens, Erlangen, Germany) prior to and after the administration of 130 ml of i.v. contrast material. Images were directly analyzed on a dedicated workstation by two radiologists to determine colonic evaluation, visualization of colonic anastomosis, presence of polyps, and extra-colonic findings. Colonic evaluation was judged as optimal in 91.7% of all colonic segments. All mechanical surgical anastomoses were visualized with CT colonography. There was no evidence of anastomotic recurrence. Seven polyps were detected in five different patients with CT colonography, with two false-positive and no false-negative examinations. Three liver metastases and two basal pulmonary nodules were also identified. Contrast-enhanced CT colonography is a feasible alternative to both conventional colonoscopy and liver ultrasonography in the follow-up of patients operated on for colorectal cancer. (orig.)

  10. Contrast-enhanced computed tomographic colonography in the follow-up of colorectal cancer patients: a feasibility study

    International Nuclear Information System (INIS)

    Laghi, Andrea; Iannaccone, Riccardo; Carbone, Iacopo; Piacentini, Francesca; Passariello, Roberto; Bria, Emilio; Trasatti, Luciana; Lauro, Salvatore; Vecchione, Aldo

    2003-01-01

    The aim of our study was to assess whether contrast-enhanced CT colonography is a feasible alternative to both conventional colonoscopy and liver ultrasonography in the follow-up program of colorectal cancer patients. Thirty-five patients, surgically treated for colorectal cancer, underwent a follow-up program that included physical examination, carcinoembryonic antigen serum assay, conventional colonoscopy, liver ultrasonography, and chest X-ray. For these patients, we added a yearly contrast-enhanced CT colonography. All CT examinations were performed with a high-resolution protocol using a multidetector spiral CT scanner (Siemens, Erlangen, Germany) prior to and after the administration of 130 ml of i.v. contrast material. Images were directly analyzed on a dedicated workstation by two radiologists to determine colonic evaluation, visualization of colonic anastomosis, presence of polyps, and extra-colonic findings. Colonic evaluation was judged as optimal in 91.7% of all colonic segments. All mechanical surgical anastomoses were visualized with CT colonography. There was no evidence of anastomotic recurrence. Seven polyps were detected in five different patients with CT colonography, with two false-positive and no false-negative examinations. Three liver metastases and two basal pulmonary nodules were also identified. Contrast-enhanced CT colonography is a feasible alternative to both conventional colonoscopy and liver ultrasonography in the follow-up of patients operated on for colorectal cancer. (orig.)

  11. A histogram modification framework and its application for image contrast enhancement.

    Science.gov (United States)

    Arici, Tarik; Dikbas, Salih; Altunbasak, Yucel

    2009-09-01

    A general framework based on histogram equalization for image contrast enhancement is presented. In this framework, contrast enhancement is posed as an optimization problem that minimizes a cost function. Histogram equalization is an effective technique for contrast enhancement. However, a conventional histogram equalization (HE) usually results in excessive contrast enhancement, which in turn gives the processed image an unnatural look and creates visual artifacts. By introducing specifically designed penalty terms, the level of contrast enhancement can be adjusted; noise robustness, white/black stretching and mean-brightness preservation may easily be incorporated into the optimization. Analytic solutions for some of the important criteria are presented. Finally, a low-complexity algorithm for contrast enhancement is presented, and its performance is demonstrated against a recently proposed method.

  12. Contrast-enhanced dedicated breast CT detection of invasive breast cancer preceding mammographic diagnosis

    Directory of Open Access Journals (Sweden)

    Nicolas D. Prionas, MD, PhD

    2015-01-01

    Full Text Available Dedicated breast computed tomography (bCT generates high-resolution, three-dimensional images of the pendent uncompressed breast. Intravenous iodinated contrast during bCT provides additional physiologic information. In this case, a 10.0-mm invasive ductal carcinoma was visualized using contrast-enhanced breast CT one year before mammographic detection. Mammography four months before bCT was negative. The bCT contrast enhancement pattern closely matched the dynamic contrast-enhanced MRI obtained after diagnosis. Lesion enhancement at contrast-enhanced breast CT matched previously published enhancement values of breast cancer. Contrast-enhanced dedicated bCT provided high-resolution tomographic images and physiologic contrast enhancement data that facilitated the detection of an early breast cancer.

  13. Contrast-enhanced ultrasonography of the liver using SonoVue

    OpenAIRE

    Ferraioli, Giovanna; Meloni, Maria Franca

    2017-01-01

    This review focuses on the use of contrast-enhanced ultrasonography (CEUS) with SonoVue (Bracco Imaging) for the diagnosis of focal liver lesions (FLLs), guidance during ablative treatment, and follow-up of liver tumors. Multicenter trials have shown that the performance of CEUS for the characterization of FLLs is similar to that of contrast-enhanced computed tomography or contrast-enhanced magnetic resonance imaging. CEUS with SonoVue has been effectively used for guiding the percutaneous tr...

  14. BMD measurements of the spine derived from sagittal reformations of contrast-enhanced MDCT without dedicated software

    Energy Technology Data Exchange (ETDEWEB)

    Baum, Thomas, E-mail: thbaum@gmx.de [Institut fuer Roentgendiagnostik, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Str. 22, 81675 Muenchen (Germany); Mueller, Dirk, E-mail: dirk.mueller@roe.med.tum.de [Institut fuer Roentgendiagnostik, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Str. 22, 81675 Muenchen (Germany); Dobritz, Martin, E-mail: dobritz@roe.med.tum.de [Institut fuer Roentgendiagnostik, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Str. 22, 81675 Muenchen (Germany); Rummeny, Ernst J., E-mail: institut@roe.med.tum.de [Institut fuer Roentgendiagnostik, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Str. 22, 81675 Muenchen (Germany); Link, Thomas M., E-mail: thomas.link@radiology.ucsf.edu [Musculoskeletal and Quantitative Imaging Research, Department of Radiology and Biomedical Imaging, University of California San Francisco, 185 Berry Street, Suite 350, San Francisco, CA 94107 (United States); Bauer, Jan S., E-mail: jsb@roe.med.tum.de [Institut fuer Roentgendiagnostik, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Str. 22, 81675 Muenchen (Germany)

    2011-11-15

    Purpose: To assess QCT equivalent BMD of the lumbar spine in sagittal reformations of routine abdominal contrast-enhanced MDCT with simple PACS measurement tools and to apply this method to MDCT datasets for differentiating patients with and without osteoporotic vertebral fractures. Materials and methods: Eight postmenopausal women (65 {+-} 5years) underwent standard QCT to assess BMD of L1-L3. Afterwards routine abdominal contrast-enhanced MDCT images of these women were obtained and apparent BMD of L1-L3 was measured using the sagittal reformations. The MDCT-to-QCT conversion equation for BMD was calculated with linear regression analysis. The conversion equation was applied to vertebral BMD datasets (L1-L3) of 75 postmenopausal women (66 {+-} 4years). Seventeen of the 75 patients had osteoporotic vertebral fractures. Results: BMD values of contrast-enhanced MDCT were on average 56 mg/ml higher than those of standard QCT. A correlation coefficient of r = 0.94 (p < 0.05) was calculated for the BMD values of MDCT and standard QCT with the conversion equation BMD{sub QCT} = 0.69 x BMD{sub MDCT} - 11 mg/ml. Accordingly converted BMD values of patients with vertebral fractures were significantly lower than those of patients without vertebral fractures (69 mg/ml vs. 85 mg/ml; p < 0.05). Using ROC analysis to differentiate patients with and without vertebral fractures, AUC = 0.72 was obtained for converted BMD values (p < 0.05). Short- and long-term reproducibility errors for BMD measurements in the sagittal reformations amounted 2.09% and 7.70%, respectively. Conclusion: BMD measurements of the spine could be computed in sagittal reformations of routine abdominal contrast-enhanced MDCT with minimal technical and time effort. Using the conversion equation, the acquired BMD data could differentiate patients with and without osteoporotic vertebral fractures.

  15. Newly Diagnosed Breast Cancer: Comparison of Contrast-enhanced Spectral Mammography and Breast MR Imaging in the Evaluation of Extent of Disease.

    Science.gov (United States)

    Lee-Felker, Stephanie A; Tekchandani, Leena; Thomas, Mariam; Gupta, Esha; Andrews-Tang, Denise; Roth, Antoinette; Sayre, James; Rahbar, Guita

    2017-11-01

    Purpose To compare the diagnostic performances of contrast material-enhanced spectral mammography and breast magnetic resonance (MR) imaging in the detection of index and secondary cancers in women with newly diagnosed breast cancer by using histologic or imaging follow-up as the standard of reference. Materials and Methods This institutional review board-approved, HIPAA-compliant, retrospective study included 52 women who underwent breast MR imaging and contrast-enhanced spectral mammography for newly diagnosed unilateral breast cancer between March 2014 and October 2015. Of those 52 patients, 46 were referred for contrast-enhanced spectral mammography and targeted ultrasonography because they had additional suspicious lesions at MR imaging. In six of the 52 patients, breast cancer had been diagnosed at an outside institution. These patients were referred for contrast-enhanced spectral mammography and targeted US as part of diagnostic imaging. Images from contrast-enhanced spectral mammography were analyzed by two fellowship-trained breast imagers with 2.5 years of experience with contrast-enhanced spectral mammography. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value were calculated for both imaging modalities and compared by using the Bennett statistic. Results Fifty-two women with 120 breast lesions were included for analysis (mean age, 50 years; range, 29-73 years). Contrast-enhanced spectral mammography had similar sensitivity to MR imaging (94% [66 of 70 lesions] vs 99% [69 of 70 lesions]), a significantly higher PPV than MR imaging (93% [66 of 71 lesions] vs 60% [69 of 115 lesions]), and fewer false-positive findings than MR imaging (five vs 45) (P mammography depicted 11 of the 11 secondary cancers (100%) and MR imaging depicted 10 (91%). Conclusion Contrast-enhanced spectral mammography is potentially as sensitive as MR imaging in the evaluation of extent of disease in newly diagnosed breast cancer, with a higher

  16. Contrast-enhanced flair imaging in the evaluation of infectious leptomeningeal diseases

    International Nuclear Information System (INIS)

    Parmar, Hemant; Sitoh, Y.-Y.; Anand, Pooja; Chua, Violet; Hui, Francis

    2006-01-01

    Purpose: The purpose of our study was to compare contrast-enhanced fluid-attenuated inversion recovery (FLAIR) images with contrast-enhanced T1 weighted images for infectious leptomeningitis. Materials and methods: We studied twenty-four patients with a clinical suspicion of infectious meningitis with unenhanced FLAIR, contrast-enhanced T1 weighted and contrast-enhanced FLAIR MR sequences. Twelve patients had cytologic and biochemical diagnosis of meningitis on cerebrospinal fluid (CSF) examination obtained 48 h before or after the MR study. Sequences were considered positive if abnormal signal was seen in the subarachnoid space (cistern or sulci) or along pial surface. Results: Twenty-seven examinations in 24 patients were performed. Of the 12 patients (thirteen studies) in whom cytology was positive, unenhanced FLAIR images were positive in six cases (sensitivity 46%), contrast-enhanced FLAIR images were positive in 11 (sensitivity 85%), and contrast-enhanced T1 weighted MR images were positive in 11 patients (sensitivity 85%). Of the 12 patients (14 studies) in whom cerebrospinal fluid study was negative, unenhanced FLAIR images were negative in 13, contrast-enhanced FLAIR images were negative in 11, and contrast-enhanced T1 weighted MR images were negative in eight. Thus, the specificity of unenhanced FLAIR, contrast-enhanced FLAIR and contrast-enhanced T1 weighted images was 93, 79 and 57%, respectively. Conclusion: Our results suggest that post-contrast FLAIR images have similar sensitivity but a higher specificity compared to contrast-enhanced T1 weighted images for detection of leptomeningeal enhancement. It can be a useful adjunct to post-contrast T1 weighted images in evaluation of infectious leptomeningitis

  17. Contrast-enhanced flair imaging in the evaluation of infectious leptomeningeal diseases

    Energy Technology Data Exchange (ETDEWEB)

    Parmar, Hemant [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore) and Department of Diagnostic Imaging, Hospital for Sick Children, Toronto (Canada)]. E-mail: parurad@hotmail.com; Sitoh, Y.-Y. [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore); Anand, Pooja [Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng (Singapore); Chua, Violet [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore); Hui, Francis [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore)

    2006-04-15

    Purpose: The purpose of our study was to compare contrast-enhanced fluid-attenuated inversion recovery (FLAIR) images with contrast-enhanced T1 weighted images for infectious leptomeningitis. Materials and methods: We studied twenty-four patients with a clinical suspicion of infectious meningitis with unenhanced FLAIR, contrast-enhanced T1 weighted and contrast-enhanced FLAIR MR sequences. Twelve patients had cytologic and biochemical diagnosis of meningitis on cerebrospinal fluid (CSF) examination obtained 48 h before or after the MR study. Sequences were considered positive if abnormal signal was seen in the subarachnoid space (cistern or sulci) or along pial surface. Results: Twenty-seven examinations in 24 patients were performed. Of the 12 patients (thirteen studies) in whom cytology was positive, unenhanced FLAIR images were positive in six cases (sensitivity 46%), contrast-enhanced FLAIR images were positive in 11 (sensitivity 85%), and contrast-enhanced T1 weighted MR images were positive in 11 patients (sensitivity 85%). Of the 12 patients (14 studies) in whom cerebrospinal fluid study was negative, unenhanced FLAIR images were negative in 13, contrast-enhanced FLAIR images were negative in 11, and contrast-enhanced T1 weighted MR images were negative in eight. Thus, the specificity of unenhanced FLAIR, contrast-enhanced FLAIR and contrast-enhanced T1 weighted images was 93, 79 and 57%, respectively. Conclusion: Our results suggest that post-contrast FLAIR images have similar sensitivity but a higher specificity compared to contrast-enhanced T1 weighted images for detection of leptomeningeal enhancement. It can be a useful adjunct to post-contrast T1 weighted images in evaluation of infectious leptomeningitis.

  18. Diagnositc value of 3D-gradient echo dynamic contrast enhanced MRI in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ik; Chung, Soo Young; Park, Hai Jung; Lee, Yul; Chung, Bong Wha; Shim, Jeong Won [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-10-01

    To assess the usefulness of 3D-gradient echo dynamic contrast enhanced MRI (3D-DMRI) in the diagnosis of breast cancer and to determine the most useful parameter for this diagnosis. Using a 1.0T MR unit, (Magnetom, Siemens, Erlaugen, Germany), 3D-DMRI (TR/TE=3D30/12) with Gd-DTPA was performed in 38 cases of breast cancer, 22 of fibroadenoma, and in three normal volunteers. We retrospectively evaluated the findings according to the speed on dynamic study and maximal amount of contrast enhancement during the delayed phase;we calculated the contrast index and morphology of the cancers and compared diagnostic accuracy among these three diagnostic parameters. On conventional spin-echo T1-and T2-weighted images, there was no significant difference of signal intensity between benign fibroadenoma and breast carcinoma. Rapid contrast enhancement (within one minute) was noted in 35 breast cancer lesions (92.1%), but relatively low and slow contrast enhancement (after five minutes) was noted in three such lesions (7.9%). Gradual contrast enhancement was noted in 21 lesions of fibroadenoma(95.5%), but a moderate degree of rapid contrast enhancement (from three to five minutes) was noted in the other case (7.9%). of On the delayed enhanced phase of 3D-DMRI, the maximal amount of contrast enhancement showed no significant difference between fibroadenoma and cancer. On 3D-DMRI, an irregular, spiculated border, with high contrast enhancement was noted in all cases of breast cancer, in particular, irregular thick peripheral contrast enhancement with central necrosis was noted 11cases(28.9%). For the diagnosis of breast cancer, 3D-DMRI is a useful technique. Among the diagnostic criteria of speed, maximal amount of contrast enhancement and morphology, morphologic change after contrast enhancement study was the most useful diagnostic parameter.=20.

  19. Diagnositc value of 3D-gradient echo dynamic contrast enhanced MRI in breast cancer

    International Nuclear Information System (INIS)

    Yang, Ik; Chung, Soo Young; Park, Hai Jung; Lee, Yul; Chung, Bong Wha; Shim, Jeong Won

    1997-01-01

    To assess the usefulness of 3D-gradient echo dynamic contrast enhanced MRI (3D-DMRI) in the diagnosis of breast cancer and to determine the most useful parameter for this diagnosis. Using a 1.0T MR unit, (Magnetom, Siemens, Erlaugen, Germany), 3D-DMRI (TR/TE=3D30/12) with Gd-DTPA was performed in 38 cases of breast cancer, 22 of fibroadenoma, and in three normal volunteers. We retrospectively evaluated the findings according to the speed on dynamic study and maximal amount of contrast enhancement during the delayed phase;we calculated the contrast index and morphology of the cancers and compared diagnostic accuracy among these three diagnostic parameters. On conventional spin-echo T1-and T2-weighted images, there was no significant difference of signal intensity between benign fibroadenoma and breast carcinoma. Rapid contrast enhancement (within one minute) was noted in 35 breast cancer lesions (92.1%), but relatively low and slow contrast enhancement (after five minutes) was noted in three such lesions (7.9%). Gradual contrast enhancement was noted in 21 lesions of fibroadenoma(95.5%), but a moderate degree of rapid contrast enhancement (from three to five minutes) was noted in the other case (7.9%). of On the delayed enhanced phase of 3D-DMRI, the maximal amount of contrast enhancement showed no significant difference between fibroadenoma and cancer. On 3D-DMRI, an irregular, spiculated border, with high contrast enhancement was noted in all cases of breast cancer, in particular, irregular thick peripheral contrast enhancement with central necrosis was noted 11cases(28.9%). For the diagnosis of breast cancer, 3D-DMRI is a useful technique. Among the diagnostic criteria of speed, maximal amount of contrast enhancement and morphology, morphologic change after contrast enhancement study was the most useful diagnostic parameter.=20

  20. A Comparative Study of Histogram Equalization Based Image Enhancement Techniques for Brightness Preservation and Contrast Enhancement

    OpenAIRE

    Patel, Omprakash; Maravi, Yogendra P. S.; Sharma, Sanjeev

    2013-01-01

    Histogram Equalization is a contrast enhancement te chnique in the image processing which uses the histogram of image. However histogram equalization is not the best method for contrast enhancement because the mean brightness of the output image is significantly different from the input image. There are several extensions of histogram equalization has be en proposed to overcome the brightness preservation cha...

  1. The role of contrast-enhanced ultrasound in risk assessment of carotid atheroma

    OpenAIRE

    Silviu Stanciu; Cristina Enciu; Ioana Răduţă; Dan Stoicescu; Adrian Anghel; Daniela Anghel; B. Olan; Lucian Ciobîcă

    2016-01-01

    Background and objective: Contrast-enhanced ultrasound, used to assess atherosclerotic carotid plaques, improves visualization of vessel wall irregularities and depicts intraplaque neovascularization. This article illustrates the use of contrast-enhanced ultrasound in the risk assessment of carotid atherosclerotic lesions, especially in challenging plaques evaluation. Materials and methods: For 23 patients with difficult duplex ultrasound examination due to carotid tortuosity o...

  2. Microwave ablation of liver metastases guided by contrast-enhanced ultrasound

    DEFF Research Database (Denmark)

    Lorentzen, T; Skjoldbye, B O; Nolsoe, C P

    2011-01-01

    The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS).......The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS)....

  3. MR imaging of the early rheumatoid arthritis: usefulness of contrast enhanced fat suppressed SPGR imaging

    International Nuclear Information System (INIS)

    Kim, Sun Mi; Joo, Kyung Bin; Kim, Seong Tae; Hahm, Chang Kok

    1995-01-01

    To evaluate value of post-contrast 3-Dimensional fat suppressed Spoiled GRASS (FS SPGR) in detecting subtle bony erosion and tenosynovitis of hands and wrists due to early rheumatoid arthritis. Fourteen MR imagings of the hands and wrists were performed in 7 early rheumatoid arthritis without any abnormalities in plain radiography and in 7 healthy volunteers. All subjects underwent MR sequence of coronal 3D FS SPGR with and without contrast enhancement in 1.5T MR unit. We evaluated the number of the bony erosion and tenosynovitis respectively in pre-and post-contrast FS SPGR images. The abnormal enhancing areas were not demonstrated in 7 healthy volunteers. Seven patients had 25 bony erosions in pre-contrast FS SPGR and 52 bony erosions with tenosynovitis (n = 10) in post-contrast FS SPGR. Enhancing joint spaces were shown in 8 cases. Post-contrast FS SPGR was better than pre-contrast FS SPGR in the evaluation of early rheumatoid arthritis and is valuable as a baseline study

  4. MR imaging of the early rheumatoid arthritis: usefulness of contrast enhanced fat suppressed SPGR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Mi; Joo, Kyung Bin; Kim, Seong Tae; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1995-06-15

    To evaluate value of post-contrast 3-Dimensional fat suppressed Spoiled GRASS (FS SPGR) in detecting subtle bony erosion and tenosynovitis of hands and wrists due to early rheumatoid arthritis. Fourteen MR imagings of the hands and wrists were performed in 7 early rheumatoid arthritis without any abnormalities in plain radiography and in 7 healthy volunteers. All subjects underwent MR sequence of coronal 3D FS SPGR with and without contrast enhancement in 1.5T MR unit. We evaluated the number of the bony erosion and tenosynovitis respectively in pre-and post-contrast FS SPGR images. The abnormal enhancing areas were not demonstrated in 7 healthy volunteers. Seven patients had 25 bony erosions in pre-contrast FS SPGR and 52 bony erosions with tenosynovitis (n = 10) in post-contrast FS SPGR. Enhancing joint spaces were shown in 8 cases. Post-contrast FS SPGR was better than pre-contrast FS SPGR in the evaluation of early rheumatoid arthritis and is valuable as a baseline study.

  5. Contrast-enhanced MRI features in the early diagnosis of Juvenile Idiopathic Arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Hemke, Robert; Maas, Mario [University of Amsterdam, Department of Radiology Academic Medical Center, Amsterdam (Netherlands); Kuijpers, Taco W.; Schonenberg-Meinema, Dieneke [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Nusman, Charlotte M. [University of Amsterdam, Department of Radiology Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Rossum, Marion A.J. van; Berg, J.M. van den [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Department of Pediatric Rheumatology, Reade, Amsterdam (Netherlands); Dolman, Koert M. [Department of Pediatric Rheumatology, Reade, Amsterdam (Netherlands); St. Lucas Andreas Hospital, Department of Pediatrics, Amsterdam (Netherlands)

    2015-11-15

    To determine whether clinical, laboratory or Magnetic Resonance Imaging (MRI) measures differentiate Juvenile Idiopathic Arthritis (JIA) from other forms of active childhood arthritis. We prospectively collected data of 80 treatment-naive patients clinically suspected of JIA with active non-infectious arthritis of (at least) one knee for <12 months duration. Upon presentation patients underwent clinical and laboratory assessments and contrast-enhanced MRI. MRI was not used as a diagnostic criterion. Forty-four (55 %) patients were clinically diagnosed with JIA, whereas in 36 (45 %) patients the diagnosis of JIA was discarded on clinical or laboratory findings. MRI-based synovitis was present in 27 (61.4 %) JIA patients and in 7 (19.4 %) non-JIA patients (P < 0.001). Five factors (male gender, physician's global assessment of overall disease activity, joints with limited range of motion, HLA-B27, MRI-based synovitis) were associated with the onset of JIA. In multivariate analysis MRI-based synovitis proved to be independently associated with JIA (OR 6.58, 95 % CI 2.36-18.33). In patients with MRI-based synovitis, the RR of having JIA was 3.16 (95 % CI 1.6-6.4). The presence of MRI-based synovitis is associated with the clinical onset of JIA. Physical examination could be supported by MRI, particularly to contribute in the early differentiation of different forms of non-infectious childhood arthritis. (orig.)

  6. Head and neck paragangliomas: diffusion weighted and dynamic contrast enhanced magnetic resonance imaging characteristics

    International Nuclear Information System (INIS)

    Yuan, Ying; Shi, Huimin; Tao, Xiaofeng

    2016-01-01

    To determine the feature values of head and neck paragangliomas on diffusion-weighted imaging (DWI) and dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI). Patients with primary head and neck paraganglioma who underwent both DWI and DCE-MRI before treatment between January 2010 and June 2013 were identified. Two radiologists assessed apparent diffusion coefficient (ADC) values on DWI and kinetic characteristics on DCE-MRI. The time intensity curves (TICs) and dynamic parameters, including peak height (PH), maximum enhancement ratio (ER max ), time to peak enhancement (T peak ) and maximum rise slope (Slope max ), were generated and evaluated. Ten patients with head and neck paraganglioma were retrospectively analyzed. On conventional MRI, the tumors demonstrated as well-circumscribed, strongly enhanced lesions. Mean ADC value of the lesions was 1.12 ± 0.15 × 10 −3 mm 2 /s. The TICs demonstrated washout pattern (type-III) in all lesions. The mean PH, ER max , T peak and Slope max value was 121.24 ± 63.99, 193.79 ± 67.18, 8.16 ± 3.29 and 25.42 ± 7.91, respectively. Head and neck paragangliomas demonstrate distinctive DWI and DCE-MRI results than for other benign tumors which should be taken into account in further evaluation of MRI on head and neck lesions

  7. Liver Function Assessment Using Parenchyma-Specific Contrast-Enhanced Ultrasonography.

    Science.gov (United States)

    Park, Jaehyung; Cho, Jinhan; Kwon, Heejin; Kang, Myongjin; Lee, Sangyun; Roh, Young-hoon; Kim, Kwan Woo; Lee, Sung Wook

    2016-02-01

    The aim of this study was to assess hepatic functional reserve by analyzing the hepatic parenchyma enhancement curve of parenchyma-specific contrast-enhanced ultrasonography (CEUS). Fifty-two patients with cirrhosis who underwent CEUS and indocyanine green tests (ICG) because of a focal liver lesion were enrolled. We evaluated the hemodynamic-related parameters of the time-intensity curve and compared these findings with the ICG retention rate at 15 min (ICG R15). The correlation between the time from peak to one half (s) and ICG R15 was statistically significant and was relatively proportional to the ICG R15. A cut-off value of 149 s was determined for the time from peak to one half for abnormal ICG R15 (>14). The sensitivity and specificity were 85.7% and 92.3%, respectively, for the detection of abnormal ICG R15. In conclusion, the time from peak to one half of the time-intensity curve of parenchyma-specific CEUS of the liver can be a useful parameter to predict the hepatic reserve in liver cirrhosis. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  8. Perfusion characteristics of parotid gland tumors evaluated by contrast-enhanced ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Klotz, Laura V., E-mail: Laura.Klotz@med.uni-muenchen.de [Department of Surgery, University of Munich, Munich (Germany); Gürkov, Robert [Department of Otorhinolaryngology, University of Munich, Munich (Germany); Eichhorn, Martin E. [Department of Surgery, University of Munich, Munich (Germany); Siedek, Vanessa; Krause, Eike [Department of Otorhinolaryngology, University of Munich, Munich (Germany); Jauch, Karl-Walter [Department of Surgery, University of Munich, Munich (Germany); Reiser, Maximilian F.; Clevert, Dirk-Andre [Department of Clinical Radiology, University of Munich, Munich (Germany)

    2013-12-01

    Purpose: Contrast enhanced ultrasound (CE-US) is a promising imaging modality for non-invasive analysis of parotid gland lesions because their vascularisation differs from normal gland tissue. This clinical study should further investigate CE-US as a diagnostic tool for parotid gland tumors. Materials and methods: 39 patients underwent CE-US measurements after intravenous application of a contrast agent (SonoVue, Bracco, Italy) before surgical tumor resection. Time–intensity curves gradients were calculated and parameters of intratumoral microcirculation were analysed. The vascularisation parameters were compared among the different tumor entities as defined per definitive histological diagnosis. Results: Histological analyses revealed 17 pleomorphic adenoma, 15 cystadenolymphoma and 7 malignoma. A significant difference of area below intensity time curve (AUC) and mean transit time (MTT) was measured in the malignant lesions compared to benign tumors (p < 0.05). A significant difference of AUC and maximum of signal increase (ΔSI{sub max}) for pleomorphic adenoma versus cystadenolymphoma was found (p < 0.05). Conclusion: CE-US seems to be a quantitative and independent method for the assessment of malign and benign parotid gland tumors. Further studies and clinical experience will have to validate this method as a reliable diagnostic tool that facilitates preoperative planning.

  9. Contrast enhanced sonography of the gallbladder: A tool in the diagnosis of cholecystitis?

    Energy Technology Data Exchange (ETDEWEB)

    Adamietz, Boris [Institute of Radiology, University of Erlangen, Maximiliansplatz 1, 91054 Erlangen (Germany)]. E-mail: boris.adamietz@idr.imed-uni-erlangen.de; Wenkel, Evelyn [Institute of Radiology, University of Erlangen, Maximiliansplatz 1, 91054 Erlangen (Germany)]. E-mail: evelyn.wenkel@idr.imed.uni-erlangen.de; Uder, Michael [Institute of Radiology, University of Erlangen, Maximiliansplatz 1, 91054 Erlangen (Germany)]. E-mail: michael.uder@idr.imed-uni-erlangen.de; Meyer, Thomas [Department of Surgery, University of Erlangen, Krankenhausstrasse 12, 91054 Erlangen (Germany)]. E-mail: thomas.meyer@chir.imed-uni-erlangen.de; Schneider, Ignaz [Department of Surgery, University of Erlangen, Krankenhausstrasse 12, 91054 Erlangen (Germany)]. E-mail: ignaz.schneider@chir.imed-uni-erlangen.de; Dimmler, Arno [Department of Pathology, University of Erlangen, Krankenhausstrasse 8-10, 91054 Erlangen (Germany)]. E-mail: arno.dimmler@patho.imed-uni-erlangen.de; Bautz, Werner [Institute of Radiology, University of Erlangen, Maximiliansplatz 1, 91054 Erlangen (Germany)]. E-mail: werner.bautz@idr.imed-uni-erlangen.de; Janka, Rolf [Institute of Radiology, University of Erlangen, Maximiliansplatz 1, 91054 Erlangen (Germany)]. E-mail: rolf.janka@idr.imed-uni-erlangen.de

    2007-02-15

    Rationale and objectives: To evaluate if contrast enhanced sonography (CES) can help to detect gallbladder inflammation and differentiate between acute and chronic cholecystitis. Materials and methods: Thirty-three patients with clinical suspicion of acute cholecystitis were examined with CES before cholecystectomy. Thirty patients with no history of gallbladder disease served as control. CES was performed using 2.5 mL SonoVue. A small mechanical index was chosen (0.1). The enhancement pattern of the gallbladder was ranked in a three-point scale: no enhancement, low enhancement and strong enhancement. 28/33 patients underwent surgery. Sonographic findings were compared to histological results. Results: In 16/20 cases with histological proven acute cholecystitis, the gallbladder wall showed a strong enhancement. Low enhancement was found in four patients with acute and in six patients with chronic cholecystitis. The gallbladder wall of two patients with chronic inflammation and all patients (30/30) of the control group showed no enhancement. Conclusion: CES is a feasible tool for detecting gallbladder inflammation. Differentiating between acute and chronic cholecystitis seems to be possible.

  10. Prospective evaluation of contrast-enhanced MR imaging after uncomplicated lumbar discography

    Energy Technology Data Exchange (ETDEWEB)

    Carrino, John A. [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Outpatient Center, Baltimore, MD (United States); Swathwood, Todd C. [Blue Ridge Orthopedic Associates, Seneca (United States); Morrison, William B. [Thomas Jefferson University Hospital, Department of Radiology, Philadelphia, PA (United States); Glover, J.M. [Northern Arizona Orthopaedics, Flagstaff, AZ (United States)

    2007-04-15

    Postdiscography infection is an uncommon complication. Magnetic resonance (MR) imaging is often the modality of choice for evaluating spinal infection. Discography entails disc access and fluid injection that could alter the baseline MR imaging appearance of the spine and be confounded for infection. Our purpose was to describe the MR imaging findings of the lumbar spine subsequent to uncomplicated discography and to determine if this may mimic infection. In a prospective cohort study of eight adults (age 22-64 years, mean 45 years) with 22 intradiscal injections, all subjects underwent routine unenhanced and contrast-enhanced MR imaging during the 2-3 week interval postdiscography. A subset of four returned for additional MR imaging during the 4-8 week interval postdiscography. MR images were reviewed for intradiscal, endplate, marrow, and epidural findings and then compared with prediscography examinations. Infection was excluded by clinical documentation. Postdiscography MR imaging showed that almost all levels were similar to baseline prediscography examinations. No levels developed new vertebral marrow edema, fluid-like intradiscal signal, endplate irregularity, or epidural abnormality. Two subjects simulated potential discitis, but these findings were unchanged from prediscography and were related to prior surgery. Uncomplicated lumbar spine discography does not cause MR imaging changes that simulate discitis. (orig.)

  11. Magnetic resonance imaging dynamic contrast enhancement (DCE) characteristics of healed myocardial infarction differ from viable myocardium.

    Science.gov (United States)

    Goldfarb, James W; Zhao, Wenguo

    2014-12-01

    To determine whether healed myocardial infarction alters dynamic contrast-enhancement (DCE) curve shapes as well as late gadolinium-enhancement (LGE). Twenty patients with chronic myocardial infarction underwent MR imaging at 1.5 T with blood and myocardial T1 measurements before and after contrast administration for forty minutes. Viable and infarcted myocardial partition coefficients were calculated using multipoint slope methods for ten different DCE sampling intervals and windows. Partition coefficients and coefficients of determination were compared with paired statistical tests to assess the linearity of DCE curve shapes over the 40 min time period. Calculated partition coefficients did not vary significantly between methods (p=0.325) for viable myocardium but did differ for infarcted myocardium (pinfarcted DCE. There was a significant difference between viable and infarcted myocardial partition coefficients estimates for all methods with the exception of methods that included measurements during the first 10 min after contrast agent administration. Myocardial partition coefficients calculated from a slope calculation vary in healed myocardial infarction based on the selection of samples due to non-linear DCE curve shapes. Partition coefficient calculations are insensitive to data sampling effects in viable myocardium due to linear DCE curve shapes. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Isoattenuating insulinomas at biphasic contrast-enhanced CT: frequency, clinicopathologic features and perfusion characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liang; Xue, Hua-dan; Sun, Hao; Wang, Xuan; He, Yong-lan; Jin, Zheng-yu [Peking Union Medical College Hospital, Department of Radiology, Beijing (China); Zhao, Yu-pei [Peking Union Medical College Hospital, Department of General Surgery, Beijing (China)

    2016-10-15

    We aimed to determine the frequency of isoattenuating insulinomas, to investigate their clinicopathological features and to assess their regional pancreatic perfusion characteristics. Institutional review board approval was obtained, and patient informed consent was waived. From July 2010 to June 2014, 170 patients (66 male, 104 female) with endogenous hyperinsulinemic hypoglycemia underwent biphasic contrast-enhanced CT before surgery, and 129 of those patients also received preoperative whole-pancreas CT perfusion. A total of 181 tumours were proved histopathologically after surgery. Enhancement pattern and regional pancreatic perfusion characteristics were analyzed. Clinical features, tumour size and pathological grading were investigated. The frequency of isoattenuating tumours was 24.9 %. Tumour size and WHO grading was not significantly different between isoattenuating and hyperattenuating tumours. Tumour-free regions had identical blood flow (BF) regardless of their location (p = 0.35). Isoattenuating tumour-harbouring regions had lower BF compared with hyperattenuating tumour-harbouring regions; both showed higher BF compared with tumour-free neighbourhood regions (all p < 0.01). For patients with isoattenuating tumours, the overall hospital stay was longer (p < 0.01). A substantial subset of insulinomas were isoattenuating on biphasic CT. CT perfusion showed higher BF in tumour-harbouring regions compared to tumour-free regions, providing a clue for tumour regionalization. (orig.)

  13. Leptomeningeal contrast enhancement in moyamoya: its potential role in postoperative assessment of circulation through the bypass

    International Nuclear Information System (INIS)

    Komiyama, M.; Nakajima, H.; Nishikawa, M.; Yasui, T.; Kitano, S.; Sakamoto, H.

    2001-01-01

    Leptomeningeal contrast enhancement (LMCE) is one of the MRI features of moyamoya. Its clinical significance, however, is not elucidated. Our purpose was to characterise LMCE on MRI and to evaluate its role in the assessment of circulation through a surgically established bypass in moyamoya. We studied 16 patients with idiopathic moyamoya (seven males, nine females, includingt four children, aged 7 to 54 years, mean 24 years) who underwent T1-weighted MRI before and after intravenous contrast medium. The presence of LMCE, its intensity and anatomical distribution, catheter angiographic findings, and relation of LMCE to the bypass surgery were assessed. More LMCE was seen in the cerebrum in most patients with moyamoya than in normal controls. LMCE in the brain stem and cerebellum was minimal, similar to that seen in the controls. LMCE was less prominent following surgery than before operation or in patients who did not undergo surgery. In three patients examined both before and after operation LMCE became less prominent following bypass surgery. As LMCE becomes less prominent after ''effective'' bypass surgery, this may be used for evaluation of effectiveness of surgery in moyamoya. (orig.)

  14. Contrast-enhanced MRI features in the early diagnosis of Juvenile Idiopathic Arthritis

    International Nuclear Information System (INIS)

    Hemke, Robert; Maas, Mario; Kuijpers, Taco W.; Schonenberg-Meinema, Dieneke; Nusman, Charlotte M.; Rossum, Marion A.J. van; Berg, J.M. van den; Dolman, Koert M.

    2015-01-01

    To determine whether clinical, laboratory or Magnetic Resonance Imaging (MRI) measures differentiate Juvenile Idiopathic Arthritis (JIA) from other forms of active childhood arthritis. We prospectively collected data of 80 treatment-naive patients clinically suspected of JIA with active non-infectious arthritis of (at least) one knee for <12 months duration. Upon presentation patients underwent clinical and laboratory assessments and contrast-enhanced MRI. MRI was not used as a diagnostic criterion. Forty-four (55 %) patients were clinically diagnosed with JIA, whereas in 36 (45 %) patients the diagnosis of JIA was discarded on clinical or laboratory findings. MRI-based synovitis was present in 27 (61.4 %) JIA patients and in 7 (19.4 %) non-JIA patients (P < 0.001). Five factors (male gender, physician's global assessment of overall disease activity, joints with limited range of motion, HLA-B27, MRI-based synovitis) were associated with the onset of JIA. In multivariate analysis MRI-based synovitis proved to be independently associated with JIA (OR 6.58, 95 % CI 2.36-18.33). In patients with MRI-based synovitis, the RR of having JIA was 3.16 (95 % CI 1.6-6.4). The presence of MRI-based synovitis is associated with the clinical onset of JIA. Physical examination could be supported by MRI, particularly to contribute in the early differentiation of different forms of non-infectious childhood arthritis. (orig.)

  15. Real time contrast enhanced ultrasonography in detection of liver metastases from gastrointestinal cancer

    Directory of Open Access Journals (Sweden)

    Righini Roberto

    2007-09-01

    Full Text Available Abstract Background Contrast enhanced ultrasound (CEUS is an imaging technique which appeared on the market around the year 2000 and proposed for the detection of liver metastases in gastrointestinal cancer patients, a setting in which accurate staging plays a significant role in the choice of treatment. Methods A total of 109 patients with colorectal (n = 92 or gastric cancer prospectively underwent computed tomography (CT scan and conventional US evaluation followed by real time CEUS. A diagnosis of metastases was made by CT or, for lesions not visibile at CT, the diagnosis was achieved by histopathology or by a malignant behavior during follow-up. Results Of 109 patients, 65 were found to have metastases at presentation. CEUS improved sensitivity in metastatic livers from 76.9% of patients (US to 95.4% (p 0.01, while CT scan reached 90.8% (p = n.s. vs CEUS, p Conclusion CEUS is more sensitive than conventional US in the detection of liver metastases and could be usefully employed in the staging of patients with gastrointestinal cancer. Findings at CEUS and CT appear to be complementary in achieving maximum sensitivity.

  16. Identification of residual tumor with intraoperative contrast-enhanced ultrasound during glioblastoma resection.

    Science.gov (United States)

    Prada, Francesco; Bene, Massimiliano Del; Fornaro, Riccardo; Vetrano, Ignazio G; Martegani, Alberto; Aiani, Luca; Sconfienza, Luca Maria; Mauri, Giovanni; Solbiati, Luigi; Pollo, Bianca; DiMeco, Francesco

    2016-03-01

    The purpose of this study was to assess the capability of contrast-enhanced ultrasound (CEUS) to identify residual tumor mass during glioblastoma multiforme (GBM) surgery, to increase the extent of resection. The authors prospectively evaluated 10 patients who underwent surgery for GBM removal with navigated ultrasound guidance. Navigated B-mode and CEUS were performed prior to resection, during resection, and after complete tumor resection. Areas suspected for residual tumors on B-mode and CEUS studies were localized within the surgical field with navigated ultrasound and samples were sent separately for histopathological analysis to confirm tumor presence. In all cases tumor remnants were visualized as hyperechoic areas on B-mode, highlighted as CEUS-positive areas, and confirmed as tumoral areas on histopathological analysis. In 1 case only, CEUS partially failed to demonstrate residual tumor because the residual hyperechoic area was devascularized prior to ultrasound contrast agent injection. In all cases CEUS enhanced B-mode findings. As has already been shown in other neoplastic lesions in other organs, CEUS is extremely specific in the identification of residual tumor. The ability of CEUS to distinguish between tumor and artifacts or normal brain on B-mode is based on its capacity to show the vascularization degree and not the echogenicity of the tissues. Therefore, CEUS can play a decisive role in the process of maximizing GBM resection.

  17. Contrast-enhanced spectral mammography in patients referred from the breast cancer screening programme

    Energy Technology Data Exchange (ETDEWEB)

    Lobbes, Marc B.I.; Wildberger, Joachim E. [Maastricht University Medical Center, Department of Radiology, Maastricht (Netherlands); GROW School for Oncology and Developmental Biology, Maastricht (Netherlands); Lalji, Ulrich; Houwers, Janneke; Nijssen, Estelle C. [Maastricht University Medical Center, Department of Radiology, Maastricht (Netherlands); Nelemans, Patty J. [Maastricht University, Department of Epidemiology, Maastricht (Netherlands); Roozendaal, Lori van; Heuts, Esther [Maastricht University Medical Center, Department of Surgical Oncology, Maastricht (Netherlands); Smidt, Marjolein L. [Maastricht University Medical Center, Department of Surgical Oncology, Maastricht (Netherlands); GROW School for Oncology and Developmental Biology, Maastricht (Netherlands)

    2014-07-15

    Feasibility studies have shown that contrast-enhanced spectral mammography (CESM) increases diagnostic accuracy of mammography. We studied diagnostic accuracy of CESM in patients referred from the breast cancer screening programme, who have a lower disease prevalence than previously published papers on CESM. During 6 months, all women referred to our hospital were eligible for CESM. Two radiologists blinded to the final diagnosis provided BI-RADS classifications for conventional mammography and CESM. Statistical significance of differences between mammography and CESM was calculated using McNemar's test. Receiver operating characteristic (ROC) curves were constructed for both imaging modalities. Of the 116 eligible women, 113 underwent CESM. CESM increased sensitivity to 100.0 % (+3.1 %), specificity to 87.7 % (+45.7 %), PPV to 76.2 % (+36.5 %) and NPV to 100.0 % (+2.9 %) as compared to mammography. Differences between conventional mammography and CESM were statistically significant (p < 0.0001). A similar trend was observed in the ROC curve. For conventional mammography, AUC was 0.779. With CESM, AUC increased to 0.976 (p < 0.0001). In addition, good agreement between tumour diameters measured using CESM, breast MRI and histopathology was observed. CESM increases diagnostic performance of conventional mammography, even in lower prevalence patient populations such as referrals from breast cancer screening. (orig.)

  18. An improved contrast enhancement algorithm for infrared images based on adaptive double plateaus histogram equalization

    Science.gov (United States)

    Li, Shuo; Jin, Weiqi; Li, Li; Li, Yiyang

    2018-05-01

    Infrared thermal images can reflect the thermal-radiation distribution of a particular scene. However, the contrast of the infrared images is usually low. Hence, it is generally necessary to enhance the contrast of infrared images in advance to facilitate subsequent recognition and analysis. Based on the adaptive double plateaus histogram equalization, this paper presents an improved contrast enhancement algorithm for infrared thermal images. In the proposed algorithm, the normalized coefficient of variation of the histogram, which characterizes the level of contrast enhancement, is introduced as feedback information to adjust the upper and lower plateau thresholds. The experiments on actual infrared images show that compared to the three typical contrast-enhancement algorithms, the proposed algorithm has better scene adaptability and yields better contrast-enhancement results for infrared images with more dark areas or a higher dynamic range. Hence, it has high application value in contrast enhancement, dynamic range compression, and digital detail enhancement for infrared thermal images.

  19. Usefulness of dynamic contrast-enhanced MRI in the evaluation of the viability of acute scaphoid fracture

    International Nuclear Information System (INIS)

    Larribe, Maud; Gay, Andre; Freire, Veronique; Bouvier, Corinne; Chagnaud, Christophe; Souteyrand, Philippe

    2014-01-01

    To evaluate the usefulness of dynamic gadolinium-enhanced magnetic resonance imaging (MRI) for assessing the viability of the proximal pole of the scaphoid in patients with acute scaphoid fractures. Eighteen consecutive patients with acute scaphoid fracture who underwent dynamic gadolinium-enhanced MRI 7 days or less before surgery were prospectively included between August 2011 and December 2012. All patients underwent MR imaging with unenhanced images, enhanced images, and dynamic enhanced images. A radiologist first classified the MRI results as necrotic or viable based on T1- and T2-weighted images only, followed by a second blinded interpretation, this time including analysis of pre- and post-gadolinium administration images and a third blinded interpretation based on the time-intensity curve of the dynamic enhanced study. The standard of reference was the histologic assessment of a cylindrical specimen of the proximal pole obtained during surgery in all patients. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for unenhanced, enhanced, and dynamic gadolinium-enhanced MRI studies. The sensitivity, specificity, PPV, and NPV were 67, 67, 50, and 80 % for unenhanced images, 83, 100, 100, and 92 for enhanced images, and 83, 92, 83, and 92 for dynamic contrast-enhanced images. Our data are consistent with previously reported data supporting contrast-enhanced MRI for assessment of viability, and showing that dynamic imaging with time-intensity curve analysis does not provide additional predictive value over standard delayed enhanced imaging for acute scaphoid fracture. (orig.)

  20. 3D Whole-Heart Coronary MR Angiography at 1.5T in Healthy Volunteers: Comparison between Unenhanced SSFP and Gd-Enhanced FLASH Sequences

    International Nuclear Information System (INIS)

    Gweon, Hye Mi; Kim, Sang Jin; Lee, Sang Min; Hong, Yoo Jin; Kim, Tae Hoon

    2011-01-01

    To validate the optimal cardiac phase and appropriate acquisition window for three-dimensional (3D) whole-heart coronary magnetic resonance angiography (MRA) with a steady-state free precession (SSFP) sequence, and to compare image quality between SSFP and Gd-enhanced fast low-angle shot (FLASH) MR techniques at 1.5 Tesla (T). Thirty healthy volunteers (M:F 25:5; mean age, 35 years; range, 24-54 years) underwent a coronary MRA at 1.5T. 3D whole-heart coronary MRA with an SSFP was performed at three different times: 1) at end-systole with a narrow (120-msec) acquisition window (ESN), 2) mid-diastole with narrow acquisition (MDN); and 3) mid-diastole with wide (170-msec) acquisition (MDW). All volunteers underwent a contrast enhanced coronary MRA after undergoing an unenhanced 3D true fast imaging with steady-state precession (FISP) MRA three times. A contrast enhanced coronary MRA with FLASH was performed during MDN. Visibility of the coronary artery and image quality were evaluated for 11 segments, as suggested by the American Heart Association. Image quality was scored by a five-point scale (1 = not visible to 5 = excellent). The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were evaluated at the proximal coronary arteries. The SSFP sequence rendered higher visibility coronary segments, higher image quality, as well as higher SNR and CNR than the Gd-enhanced FLASH technique at 1.5T (p < 0.05). The visibility of coronary segments, image quality, SNR and CNR in the ESN, MDN and MDW with SSFP sequence did not differ significantly. An SSFP sequence provides an excellent method for the 3D whole-heart coronary MRA at 1.5T. Contrast enhanced coronary MRA using the FLASH sequence does not help improve the visibility of coronary segments, image quality, SNR or CNR on the 3D whole-heart coronary MRA.

  1. Fibroadenomas of the breast: histopathological/dynamic contrast-enhanced MR correlation

    International Nuclear Information System (INIS)

    Gilles, R.; Garnier, C.; Meingan, P.; Zemoura, L.; Lucidarme, O.; Guinebretiere, J.M.; Tardivon, A.A.; Arriagada, R.

    1995-01-01

    A total of 22 women with fibroadenomas had preoperative dynamic MR study (T1-weighted images every 47 s after injection of Gd-DOTA). Their age, hormonal status, breast MR studies and histopathological slides were retrospectively reviewed. Eleven pre- (n = 2) or post-menopausal (n = 9) women showed no early contrast enhancement. The absence of early contrast enhancement correlated with hyalin stromal component. Eleven pre- (n = 7) or post-menopausal (n = 4) women showed focal (n = 9) or diffuse (n = 2) early contrast enhancement. Early focal contrast enhancement correlated with myxoid (n = 9), mixed hyalin/myxoid (n 1) or hyalin (n = 1) fibroadenomas. Early diffuse contrast enhancement of the breast correlated with myxoid (n = 1) or hyalin (n = 1) stromal component associated with proliferative fibrocystic disease of the breast parenchyma. The presence of contrast enhancement correlated with myxoid fibroadenomas, whereas absence of contrast enhancement correlated with hyalin fibroadenomas. As hyalin fibroadenomas occurs in post-menopausal women, the diagnostic accuracy of dynamic MRI may be improved in this age group. (orig.)

  2. Contrast-enhanced ultrasonography depicts small tumor vessels for the evaluation of pancreatic tumors

    International Nuclear Information System (INIS)

    Okamoto, Yuko; Kawamoto, Hirofumi; Takaki, Akinobu; Ishida, Etsuji; Ogawa, Tsuneyoshi; Kuwaki, Kenji; Kobayashi, Yoshiyuki; Sakaguchi, Kohsaku; Shiratori, Yasushi

    2007-01-01

    Objective: The aim of this study is to evaluate the efficacy of contrast-enhanced ultrasonography for the diagnosis of pancreatic tumors. Materials and methods: Contrast-enhanced ultrasonography with Levovist was performed on 62 consecutive patients (53 with pancreatic cancer, 4 with islet cell tumor, 3 with inflammatory pancreatic tumor, and 2 with metastatic tumor). The vascular and perfusion image phases of the tumors were evaluated and compared with the findings of contrast-enhanced computed tomography. Results: Contrast-enhanced ultrasonography showed tumor vessels around and/or in the tumor at the vascular image phase in 79% of pancreatic cancer patients (42/53). At the perfusion image phase, 96% of pancreatic cancers (51/53) were classified as hypo-enhancement type. However, tiny spotty or irregular heterogeneous enhanced lesions were found in 84% of hypo-enhanced pancreatic cancer patients (43/51). The presence of small vessels at the vascular image phase was closely correlated with the presence of these intratumor regional enhanced lesions at the perfusion image phase (κ coefficient = 0.42). The sensitivity of contrast-enhanced ultrasonography (100%) for pancreatic cancer was superior to that of contrast-enhanced computed tomography (91%), but no significant difference was observed between the two (McNemar test: p = 0.063). Conclusion: Contrast-enhanced ultrasonography with Levovist successfully visualizes fine vessels and enhancement in pancreatic tumors, and is useful for evaluating pancreatic tumors

  3. Value of fusion of PET and MRI for staging of endometrial cancer: Comparison with {sup 18}F-FDG contrast-enhanced PET/CT and dynamic contrast-enhanced pelvic MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, Kazuhiro, E-mail: kitajima@med.kobe-u.ac.jp [Department of Radiology, Kobe University School of Medicine, Kobe (Japan); Suenaga, Yuko; Ueno, Yoshiko [Department of Radiology, Kobe University School of Medicine, Kobe (Japan); Kanda, Tomonori [Department of Obsterics and Gynecology of Kobe University School of Medicine, Kobe (Japan); Department of Radiology, Hyogo Cancer Center, Hyogo (Japan); Maeda, Tetsuo; Takahashi, Satoru [Department of Radiology, Kobe University School of Medicine, Kobe (Japan); Ebina, Yasuhiko; Miyahara, Yoshiya; Yamada, Hideto [Department of Obsterics and Gynecology of Kobe University School of Medicine, Kobe (Japan); Department of Radiology, Hyogo Cancer Center, Hyogo (Japan); Sugimura, Kazuro [Department of Radiology, Kobe University School of Medicine, Kobe (Japan)

    2013-10-01

    Purpose: To investigate the diagnostic value of retrospective fusion of pelvic MRI and {sup 18}F-fluorodeoxyglucose ({sup 18}F-FDG) PET images for assessment of locoregional extension and nodal staging of endometrial cancer. Materials and methods: Thirty patients with biopsy-proven endometrial cancer underwent preoperative contrast-enhanced PET/CT (PET/ceCT) and pelvic dynamic contrast-enhanced MRI for initial staging. Diagnostic performance of PET/ceCT, contrast-enhanced MRI, and retrospective image fusion from PET and MRI (fused PET/MRI) for assessing the extent of the primary tumor (T stage) and metastasis to regional LNs (N stage) was evaluated by two experienced readers. Histopathological and follow-up imaging results were used as the gold standard. The McNemar test was employed for statistical analysis. Results: Fused PET/MRI and MRI detected 96.7% of the primary tumors, whereas PET/ceCT detected 93.3%. Accuracy for T status was 80.0% for fused PET/MRI, and MRI proved significantly more accurate than PET/ceCT, which had an accuracy of 60.0% (p = 0.041). Patient-based sensitivity, specificity and accuracy for detecting pelvic nodal metastasis were 100%, 96.3% and 96.7% for both fused PET/MRI and PET/ceCT, and 66.7%, 100% and 96.7% for MRI, respectively. These three parameters were not statistically significant (p = 1). Conclusion: Fused PET/MRI, which complements the individual advantages of MRI and PET, is a valuable technique for assessment of the primary tumor and nodal staging in patients with endometrial cancer.

  4. Confident Diagnosis of Bronchobiliary Fistula Using Contrast-Enhanced Magnetic Resonance Cholangiography

    International Nuclear Information System (INIS)

    Karabulut, Nevzat; Cakmak, Vefa; Kiter, Go ksel

    2010-01-01

    We report the utility of contrast-enhanced magnetic resonance cholangiography (MRC) using gadoxetic acid (Gd-EOB-DTPA) in the diagnosis of bronchobiliary fistula associated with liver hydatid cyst. Contrast-enhanced MRC clearly delineated the leakage of contrast agent from the biliary duct and its communication with the bronchial tree. Providing functional information about physiologic or pathologic biliary flow in addition to the display of biliary anatomy, contrast enhanced MRC stands as a robust technique in confidently detecting bronchobiliary fistula and bile leaks

  5. Characterization of Small (Accuracy of Spectral Analysis Using Single-Phase Contrast-Enhanced Dual-Energy CT.

    Science.gov (United States)

    Patel, Bhavik N; Bibbey, Alex; Choudhury, Kingshuk R; Leder, Richard A; Nelson, Rendon C; Marin, Daniele

    2017-10-01

    The purpose of this study is to determine whether single-phase contrast-enhanced dual-energy quantitative spectral analysis improves the accuracy of diagnosis of small (men and 41 women; mean age, 54 years) with 144 renal lesions (111 benign and 33 malignant) underwent single-energy unenhanced and dual-energy contrast-enhanced CT of the abdomen. For each renal lesion, attenuation measurements were obtained, and an attenuation change of 15 HU or greater was considered evidence of enhancement. Dual-energy spectral attenuation curves were generated for each lesion. The slope of each curve was measured between 40 and 50 keV (λHU 40-50 ), 40 and 70 keV (λHU 40-70 ), and 40 and 140 keV (λHU 40-140 ). Mean lesion attenuation values and spectral attenuation curve parameters were compared between benign and malignant renal lesions by use of the two-sample t test. Diagnostic accuracy was assessed and validated using cross-validation analysis. With the use of cross-validated optimal thresholds at 100% sensitivity, specificity for differentiating between benign and malignant renal lesions improved significantly when both λHU 40-70 and λHU 40-140 were used, compared with conventional enhancement measurements (93% [103/111; 95% CI, 86-97%] vs 81% [90/111; 95% CI, 73-88%]) (p = 0.02). The sensitivity of λHU 40-70 and λHU 40-140 was also higher than that of conventional enhancement measurements, although it was not statistically significant. Single-phase contrast-enhanced dual-energy quantitative spectral analysis significantly improves the specificity for characterization of small (< 4.0 cm) renal lesions, compared with conventional single-energy attenuation measurements.

  6. Assessment of arterial hypervascularity of hepatocellular carcinoma: comparison of contrast-enhanced US and gadoxetate disodium-enhanced MR imaging

    International Nuclear Information System (INIS)

    Sugimoto, Katsutoshi; Moriyasu, Fuminori; Taira, Junichi; Imai, Yasuharu; Shiraishi, Junji; Saito, Kazuhiro; Saguchi, Toru

    2012-01-01

    To compare contrast-enhanced (CE) ultrasound with gadoxetate disodium-enhanced magnetic resonance (MR) imaging in the assessment of arterial hypervascularity of hepatocellular carcinoma (HCC) and dysplastic nodule (DN), with CT during hepatic arteriography (CTHA) as the reference standard. This study included 54 consecutively diagnosed patients, with 57 histologically confirmed HCCs and 3 DNs (high-grade). All patients underwent CE ultrasound, gadoxetate disodium-enhanced MR imaging and CTHA. Two trained diagnostic radiologists interpreted the CTHA images and rated the degree of intratumoral arterial vascularity by consensus using a five-point confidence scale as the reference standard. In the observer study, the degrees of vascularity on CE ultrasound and gadoxetate disodium-enhanced MR images were qualitatively analysed by four independent readers using a five-point confidence scale. Diagnostic accuracy was analysed by receiver-operating characteristic (ROC) analysis. The diagnostic accuracies of the average area under the ROC curve (AUC) were significantly greater with CE ultrasound (average AUC: 0.94; 95% confidence interval [CI]: 0.88-1.00) than with gadoxetate disodium-enhanced MR imaging (average AUC 0.84, 95% CI 0.74-0.93, P = 0.0014). Contrast-enhanced ultrasound yields a significantly higher AUC value than gadoxetate disodium-enhanced MR imaging in the assessment of arterial hypervascularity of HCC and DN. Key Points circle Arterial hypervascularity is an important feature determining treatment options in hepatocellular carcinoma. circle It can be assessed by contrast-enhanced (CE) ultrasound or magnetic resonance (MR) imaging. circle CE ultrasound was more accurate than Gd-EOB-DTPA MRI in assessing intratumoral vascularity. circle Hypovascular hepatic nodules should be further investigated using CE ultrasound. (orig.)

  7. Biliary complications following orthotopic liver transplantation: May contrast-enhanced MR Cholangiography provide additional information?

    Directory of Open Access Journals (Sweden)

    Piero Boraschi

    2016-01-01

    Conclusions: Contrast-enhanced T1-weighted MR Cholangiography may improve the level of diagnostic confidence provided by conventional T2-weighted MR Cholangiography in the evaluation of biliary complications after orthotopic liver transplantation.

  8. Improvement of observer performance during fluoroscopy by local adaptive contrast enhancement

    International Nuclear Information System (INIS)

    Gould, R.G.; Demas, B.E.; Maroney, T.P.

    1988-01-01

    The ability of a video processor (FluoroVision FV-1), which performs two-dimensional locally adaptive contrast enhancement, to improve the detection of a low-contrast object was evaluated by means of receiver operating characteristic (ROC) curves. Three independent observers viewed a videotape of 50 fluoroscopic images of a varied background, in which a test object was present in 25. Each observer viewed the tape under four conditions: (1) no processing, (2) temporal noise reduction (gaussian weighted time averaging, (3) contrast enhancement, and (4) both noise reduction and contrast enhancement. The results were that detection was significantly improved by the locally adaptive contrast enhancement. Noise reduction did not significantly improve performance, probably because washer detection was limited by background contrast variations as well as noise and because only a small amount of noise reduction was used. The authors conclude that the processing device is potentially valuable in improving the quality of clinical fluoroscopic images

  9. Contrast-enhanced ultrasonographic findings in three dogs with lung lobe torsion.

    Science.gov (United States)

    Caivano, Domenico; Birettoni, Francesco; Bufalari, Antonello; De Monte, Valentina; Angeli, Giovanni; Giorgi, Maria Elena; Patata, Valentina; Porciello, Francesco

    2016-03-01

    Lung lobe torsion is rare but life-threatening condition in the dog. Thoracic radiographs and conventional ultrasonography cannot be conclusive for the diagnosis, and computed tomography is useful but is limited by cost and availability. This report describes the findings of contrast-enhanced ultrasonography in 3 dogs with lung lobe torsion. Contrast-enhanced ultrasonography showed the absence or reduction of pulmonary vascularization secondary to twisting of the lung lobe around its bronchovascular pedicle in all three dogs. Moreover, contrast-enhanced ultrasonography distinguished partial pulmonary atelectasis from a lung lobe torsion. These preliminary results suggest that contrast-enhanced ultrasonography can improve the accuracy of conventional ultrasonography for detection of pulmonary blood flow compromise in dogs with lung lobe torsion.

  10. The role of contrast-enhanced ultrasonography in image-guided liver ablations

    Energy Technology Data Exchange (ETDEWEB)

    Pescatori, Lorenzo Carlo [Postgraduate School in Radiodiagnostics, University Studi di Milano, Milan (Italy); Sconfienza, Luca Maria; Mauri, Giovanni [Radiology Unit, Policlinico San Donato Research Hospital, Milan (Italy)

    2016-01-15

    We read with great interest the paper by Kim et al. entitled “Local ablation therapy with contrast enhanced ultrasonography for hepatocellular carcinoma: a practical review,” recently published in Ultrasonography. We think that contrast-enhanced ultrasonography (CEUS), together with the development of reliable navigation systems, is likely to represent one of the most important advances in image-guided ablations in recent years. Thus, we offer some considerations on the topic.

  11. Breast contrast-enhanced ultrasound: is a scoring system feasible? A preliminary study in China.

    Directory of Open Access Journals (Sweden)

    Xiaoyun Xiao

    Full Text Available Although many studies about breast contrast-enhanced ultrasound had been conducted, clear diagnostic criteria for evaluating enhancement patterns are still lacking. This study aims to identify significant indicators for breast contrast-enhanced ultrasound and to establish an initial scoring system.Totally 839 patients were included in the study. This study was divided into two parts. 364 patients were included in part 1 while 475 in part 2. Conventional ultrasound and contrast-enhanced ultrasound were used to examine each lesion. Only the cases in part 2 were also examined by elastography. In part 1, Logistic regression analysis was performed to predict significant variables. A 5-point scoring system was developed based on the results. In part 2, the scoring system was used to evaluate all the breast lesions. To evaluate the diagnostic efficacy of the new scoring system, it was compared with the system established for elastography and conventional ultrasound (BI-RADS.Three independent variables, namely, lesion scope, margin, and shape were selected in the final step of the logistic regression analysis in part 1. In part 2, the area under the ROC (receiver operating characteristic curve for the contrast-enhanced scoring system was 0.912. The difference in the diagnostic capabilities of the contrast-enhanced scoring system and elastography was not statistically significant (P = 0.17. The difference in the diagnostic capabilities of the contrast-enhanced scoring system and BI-RADS was statistically significant (P<0.001.The contrast-enhanced patterns of benign and malignant breast tumors are different. The application of a 5-point scoring system for contrast-enhanced ultrasound is clinically promising.

  12. Contrast-enhanced CT and diffusion-weighted MR imaging: Performance as a prognostic factor in patients with pancreatic ductal adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Fukukura, Yoshihiko, E-mail: fukukura@m.kufm.kagoshima-u.ac.jp [Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City 890-8544 (Japan); Takumi, Koji [Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City 890-8544 (Japan); Higashi, Michiyo [Department of Human Pathology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City 890-8544 (Japan); Shinchi, Hiroyuki [Department of Surgical Oncology and Digestive Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City 890-8544 (Japan); Kamimura, Kiyohisa; Yoneyama, Tomohide; Tateyama, Akihiro [Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City 890-8544 (Japan)

    2014-04-15

    Objective: To determine whether contrast enhancement of CT and apparent diffusion coefficient on diffusion-weighted MR imaging are important parameters that can predict outcomes for patients with pancreatic ductal adenocarcinoma. Materials and methods: Ninety-two patients with histologically confirmed pancreatic ductal adenocarcinoma who underwent quadriphasic CT (including unenhanced, pancreatic parenchymal, portal venous and delayed phases) and fat-suppressed single-shot echo-planar diffusion-weighted MR imaging at 3.0 T were retrospectively analyzed to investigate prognostic factors. Overall survival curves were drawn using the Kaplan–Meier method. Effects on survival of variables including age, sex, tumor location, tumor size, TNM stage, carbohydrate antigen 19-9, carcinoembryonic antigen, treatment, tumor contrast enhancement and apparent diffusion coefficient values were analyzed in univariate analysis using the log-rank test. Variables were analyzed in multivariate analyses using the Cox proportional hazards regression model. Results: Median survival for the entire patient population was 18.2 months. Higher contrast enhancement during all phases was associated with significantly longer overall survival (P < 0.001 for all phases). The difference in overall survival between groups divided by median apparent diffusion coefficient value was not significant (P = 0.672). TNM stage (P = 0.026) and tumor contrast enhancement on CT (P = 0.027) were significantly related to survival in multivariate analysis. Conclusions: Poor enhancement of pancreatic adenocarcinomas on enhanced CT is associated with reduced patient survival.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-09-15

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

  14. Dynamic contrast-enhanced MR imaging of endometrial cancer. Optimizing the imaging delay for tumour-myometrium contrast

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Bin [Chung-Ang University Hospital, Chung-Ang University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Moon, Min Hoan; Sung, Chang Kyu [Seoul National University College of Medicine, 41, Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); Oh, Sohee [Seoul National University College of Medicine, 41, Department of Biostatistics, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); Lee, Young Ho [Kwandong University College of Medicine, Department of Radiology, Cheil General Hospital and Women' s Healthcare Center, Seoul (Korea, Republic of)

    2014-11-15

    To investigate the optimal imaging delay time of dynamic contrast-enhanced magnetic resonance (MR) imaging in women with endometrial cancer. This prospective single-institution study was approved by the institutional review board, and informed consent was obtained from the participants. Thirty-five women (mean age, 54 years; age range, 29-66 years) underwent dynamic contrast-enhanced MR imaging with a temporal resolution of 25-40 seconds. The signal intensity difference ratios between the myometrium and endometrial cancer were analyzed to investigate the optimal imaging delay time using single change-point analysis. The optimal imaging delay time for appropriate tumour-myometrium contrast ranged from 31.7 to 268.1 seconds. The median optimal imaging delay time was 91.3 seconds, with an interquartile range of 46.2 to 119.5 seconds. The median signal intensity difference ratios between the myometrium and endometrial cancer were 0.03, with an interquartile range of -0.01 to 0.06, on the pre-contrast MR imaging and 0.20, with an interquartile range of 0.15 to 0.25, on the post-contrast MR imaging. An imaging delay of approximately 90 seconds after initiating contrast material injection may be optimal for obtaining appropriate tumour-myometrium contrast in women with endometrial cancer. (orig.)

  15. Assessment of chronic thromboembolic pulmonary hypertension by three-dimensional contrast-enhanced MR angiography - comparison with selective intraarterial DSA

    International Nuclear Information System (INIS)

    Kreitner, K.F.; Ley, S.; Kauczor, H.U.; Kalden, P.; Pitton, M.B.; Thelen, M.; Mayer, E.; Laub, G.

    2000-01-01

    Purpose: This study compares contrast-enhanced 3D-MR angiography (MRA) of the pulmonary arteries with selective intraarterial DSA in patients with chronic thromboembolic pulmonary hypertension. Materials and methods: 20 patients preoperatively underwent a contrast-enhanced 3D-MRA of the pulmonary arteries at 1.5 T using the phased-array body coil. For MRA, we used a 3D-Flash-sequence after bolus timing. 2 radiologists analyzed the acquired image material in consensus with respect to the detection of central thromboembolic material and the visualization of the pulmonary arterial tree. Finally, the MR angiograms were compared with selective DSA images using surgical findings as the definitive standard. Results: MRA demonstrated central thromboembolic material, vessel cut-offs and abnormal proximal-to-distal tapering in all patients. Compared to DSA, MRA depicted the pulmonary vessels up to the segmental level in all cases, it was inferior to DSA in delineation of the subsegmental arteries (sensitivity 87%, specificity 100%). The central beginning of the thromboembolic occlusions seen at MRA corresponded to the beginning of the deobliteration procedure during pulmonary thromboendarterectomy in every case. (orig.) [de

  16. Dynamic contrast-enhanced MR imaging of endometrial cancer. Optimizing the imaging delay for tumour-myometrium contrast

    International Nuclear Information System (INIS)

    Park, Sung Bin; Moon, Min Hoan; Sung, Chang Kyu; Oh, Sohee; Lee, Young Ho

    2014-01-01

    To investigate the optimal imaging delay time of dynamic contrast-enhanced magnetic resonance (MR) imaging in women with endometrial cancer. This prospective single-institution study was approved by the institutional review board, and informed consent was obtained from the participants. Thirty-five women (mean age, 54 years; age range, 29-66 years) underwent dynamic contrast-enhanced MR imaging with a temporal resolution of 25-40 seconds. The signal intensity difference ratios between the myometrium and endometrial cancer were analyzed to investigate the optimal imaging delay time using single change-point analysis. The optimal imaging delay time for appropriate tumour-myometrium contrast ranged from 31.7 to 268.1 seconds. The median optimal imaging delay time was 91.3 seconds, with an interquartile range of 46.2 to 119.5 seconds. The median signal intensity difference ratios between the myometrium and endometrial cancer were 0.03, with an interquartile range of -0.01 to 0.06, on the pre-contrast MR imaging and 0.20, with an interquartile range of 0.15 to 0.25, on the post-contrast MR imaging. An imaging delay of approximately 90 seconds after initiating contrast material injection may be optimal for obtaining appropriate tumour-myometrium contrast in women with endometrial cancer. (orig.)

  17. Contrast-enhanced CMR in patients after percutaneous closure of the left atrial appendage: A pilot study

    Directory of Open Access Journals (Sweden)

    Petersen Steffen E

    2011-07-01

    Full Text Available Abstract Background To evaluate the feasibility and value of first-pass contrast-enhanced dynamic and post-contrast 3D CMR in patients after transcatheter occlusion of left atrial appendage (LAA to identify incorrect placement and persistent leaks. Methods 7 patients with different occluder systems (n = 4 PLAATO; n = 2 Watchman; n = 1 ACP underwent 2 contrast-enhanced (Gd-DOTA CMR sequences (2D TrueFISP first-pass perfusion and 3D-TurboFLASH to assess localization, artifact size and potential leaks of the devices. Perfusion CMR was analyzed visually and semi-quantitatively to identify potential leaks. Results All occluders were positioned within the LAA. The ACP occluder presented the most extensive artifact size. Visual assessment revealed a residual perfusion of the LAA apex in 4 cases using first-pass perfusion and 3D-TurboFLASH indicating a suboptimal LAA occlusion. By assessing signal-to-time-curves the cases with a visually detected leak showed a 9-fold higher signal-peak in the LAA apex (567 ± 120% increase from baseline signal than those without a leak (61 ± 22%; p Conclusion This CMR pilot study provides valuable non-invasive information in patients after transcatheter occlusion of the LAA to identify correct placement and potential leaks. We recommend incorporating CMR in future clinical studies to evaluate new device types.

  18. Visualization of novel microstents in patients with unruptured intracranial aneurysms with contrast-enhanced flat panel detector CT.

    Science.gov (United States)

    Poncyljusz, Wojciech; Zwarzany, Łukasz; Safranow, Krzysztof

    2015-07-01

    The aim of our study was to evaluate the feasibility of contrast-enhanced flat panel detector CT (FPDCT) for visualizing the novel microstents implanted in patients with unruptured wide-necked intracranial aneurysms. Forty-four cases of patients who underwent stent assisted coiling at our department were retrospectively analyzed. In each case, FPDCT images were performed after stent and coils deployment and then assessed in the terms of stent struts and all radiopaque markers and tantalum strands visibility separately using a 3-grade scale (1 - inadequate, 2 - good, 3 - excellent). Stent struts visibility was assessed to be inadequate for evaluation in all cases. All radiopaque markers and tantalum strands visibility was excellent in 61.4% and good in 38.6% of cases. We observed 4 (9.09%) cases of incomplete stent opening. Treated aneurysm size <10mm was an independent predictor of excellent stent all radiopaque markers and tantalum strands visibility (ρ=0.014). Contrast-enhanced FPDCT is feasible for visualizing stents implanted in patients with intracranial aneurysms as it gives precise visualization of the relationships between the stent tantalum strands and the vessel wall. Stents used in the treatment of aneurysms ≥10 mm in size are worse visualized because of the coil streaking artifacts. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Does Contrast-Enhanced Cervical Ultrasonography Improve Preoperative Localization Results in Patients With Sporadic Primary Hyperparathyroidism?

    Directory of Open Access Journals (Sweden)

    Elias Karakas

    2012-01-01

    Full Text Available Objective: Pre-operative localization studies are inevitable in patients with primary hyperparathyroidism (pHPT, who are eligible for focused or minimally invasive parathyroidectomy (MIP. High-resolution ultrasonography (US in combination with planar 99m Tc-Sestamibi-scintigraphy (MIBI and additional single-photon emission computed tomography (SPECT are the standard procedures to localize enlarged parathyroid glands. Our aim was to evaluate the practicability and significance of contrast-enhanced ultrasonography (CEUS in patients with pHPT. Materials and Methods: All investigations were performed at the University Hospital Marburg. Totally, 25 patients with biochemical proven pHPT underwent preoperative US, MIBI/SPECT, and CEUS. For CEUS, a suspension of phospholipid-stabilized sulfur-hexafluoride (SF6 microbubbles in combination with a special 12 MHz linear US probe was used. All patients were investigated by two sonographers, who did not get to view the findings noted by the other. Finally, surgery was performed and histopathological results were obtained from 24 patients. Results: In 17 (68% patients, US and MIBI/SPECT already raised suspicion of parathyroid lesions and all suspected lesions were reassessed by CEUS. However, no additional information was obtained using CEUS. Especially in eight patients with negative or inconsistent US and MIBI/SPECT results, CEUS did not provide additional information regarding the site of the suspected parathyroid adenoma. Overall, no side effects were observed using CEUS. Surgical cure was achieved in all patients. Conclusion: In this limited cohort of patients, no additional information could be obtained using the costly CEUS compared to results of US and MIBI/SPECT.

  20. Intravenous contrast enhanced computed tomography colonoscopy in children with suspected colonic polyps.

    Science.gov (United States)

    Bhatia, Anmol; Saxena, Akshay K; Kalra, Naveen; Sodhi, Kushaljit S; Thapa, Babu R; Rao, Katragadda L N; Khandelwal, Niranjan

    2013-06-01

    The purpose of this study was to evaluate the diagnostic performance of intravenous contrast enhanced computed tomographic colonoscopy (IVCTC) in the diagnosis of clinically suspected colorectal polyps in children, using conventional colonoscopy (CC) as the gold standard. This was a prospective study conducted between July 2008 and June 2010. 30 pediatric patients with history of rectal bleeding and clinically suspected to have colorectal polyps were enrolled. All of the patients underwent IVCTC followed by CC. 30 IVCTC and 31 CC were performed in 30 patients. The findings of IVCTC were compared with those of CC. Statistical analysis was performed to obtain diagnostic performance values of IVCTC on per polyp (sensitivity and positive predictive value) and per patient (sensitivity, specificity, positive predictive value and negative predictive value) basis. By IVCTC, 63 polyps were detected in 28 patients of which 53 polyps were eligible for inclusion in the statistical analysis. 60 polyps were detected by CC in 28 patients of which 50 polyps were eligible for inclusion in the statistical analysis. The per polyp sensitivity and positive predictive values were 94% and 88.6% respectively. The per patient sensitivity, specificity, positive predictive value, and negative predictive values were 96.4, 50, 96.4, and 50% respectively. Twenty polyps, in 10 patients, were visualized only after intravenous contrast administration of which 5 polyps, in 5 patients, were likely to have been missed in the absence of the intravenous contrast injection as these polyps were submerged in fluid. Four patients would have had a false negative CTC examination if the intravenous contrast had not been injected; while in another patient, the number of polyps would have been underestimated. CTC is capable of serving as a safe and efficient non-invasive tool for evaluating children with clinically suspected colorectal polyps. Administration of intravenous contrast improves the sensitivity of

  1. Predictive factors of contrast-enhanced ultrasonography for the response to transarterial chemoembolization in hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Kil Hyo Park

    2015-06-01

    Full Text Available Background/AimsThe predictive role of contrast-enhanced ultrasonography (CEUS before performing transarterial chemoembolization (TACE has not been determined. We assessed the possible predictive factors of CEUS for the response to TACE.MethodsSeventeen patients with 18 hepatocellular carcinoma (HCC underwent TACE. All of the tumors were studied with CEUS before TACE using a second-generation ultrasound contrast agent (SonoVue®, Bracco, Milan, Italy. The tumor response to TACE was classified with a score between 1 and 4 according to the remaining enhancing-tumor percentage based on modified response evaluation criteria in solid tumors (mRECIST: 1, enhancing tumor <25%; 2, 25%≤enhancing tumor<50%; 3, 50%≤enhancing tumor<75%; and 4, enhancing tumor≥75%. A score of 1 was defined as a "good response" to TACE. The predictive factors for the response to TACE were evaluated during CEUS based on the maximum tumor diameter, initial arterial enhancing time, arterial enhancing duration, intensity of arterial enhancement, presence of a hypoenhanced pattern, and the feeding artery to the tumor.ResultsThe median tumor size was 3.1 cm. The distribution of tumor response scores after TACE in all tumors was as follows: 1, n=11; 2, n=4; 3, n=2; and 4, n=1. Fifteen tumors showed feeding arteries. The presence of a feeding artery and the tumor size (≤5 cm were the predictive factors for a good response (P=0.043 and P=0.047, respectively.ConclusionsThe presence of a feeding artery and a tumor size of less than 5 cm were the predictive factors for a good response of HCC to TACE on CEUS.

  2. Contrast-enhanced ultrasound in portal venous system aneurysms: A multi-center study

    Science.gov (United States)

    Tana, Claudio; Dietrich, Christoph F; Badea, Radu; Chiorean, Liliana; Carrieri, Vincenzo; Schiavone, Cosima

    2014-01-01

    AIM: To investigate contrast-enhanced ultrasound (CEUS) findings in portal venous system aneurysms (PVSAs). METHODS: In this multi-center, retrospective, case series study, we evaluated CEUS features of seven cases of PVSAs that were found incidentally on conventional ultrasound in the period 2007-2013. Three Ultrasound Centers were involved (Chieti, Italy, Bad Mergentheim, Germany, and Cluj-Napoca, Romania). All patients underwent CEUS with Sonovue® (Bracco, Milan, Italy) at a standard dose of 2.4 mL, followed by 10 mL of 0.9% saline solution. The examinations were performed using multifrequency transducers and low mechanical index. We considered aneurysmal a focal dilatation of the portal venous system with a size that was significantly greater than the remaining segments of the same vein, and that was equal or larger than 21 mm for the extrahepatic segments of portal venous system, main portal vein and bifurcation, and 9 mm for the intrahepatic branches. RESULTS: After contrast agent injection, all PVSAs were not enhanced in the arterial phase (starting 8-22 s). All PVSAs were then rapidly enhanced in the early portal venous phase (starting three to five seconds after the arterial phase, 11-30 s), with persistence and slow washout of the contrast agent in the late phase (starting 120 s). In all patients, CEUS confirmed the presence of a “to-and-fro” flow by showing a swirling pattern within the dilatation in the early portal venous phase. CEUS also improved the delineation of the lumen, and was reliable in showing its patency degree and integrity of walls. In one patient, CEUS showed a partial enhancement of the lumen with a uniformly nonenhancing area in the portal venous and late phases, suggesting thrombosis. CONCLUSION: In our case series, we found that CEUS could be useful in the assessment and follow-up of a PVSA. Further studies are needed to validate its diagnostic accuracy. PMID:25561805

  3. Contrast-enhanced ultrasound evaluation of hepatic microvascular changes in liver diseases.

    Science.gov (United States)

    Ridolfi, Francesco; Abbattista, Teresa; Busilacchi, Paolo; Brunelli, Eugenio

    2012-10-07

    To assess if software assisted-contrast-enhanced ultrasonography (CEUS) provides reproducible perfusion parameters of hepatic parenchyma in patients affected by chronic liver disease. Forty patients with chronic viral liver disease, with (n = 20) or without (n = 20) cirrhosis, and 10 healthy subjects underwent CEUS and video recordings of each examination were then analysed with Esaote's Qontrast software. CEUS dedicated software Qontrast was used to determine peak (the maximum signal intensity), time to peak (TTP), region of blood value (RBV) proportional to the area under the time-intensity curve, mean transit time (MTT) measured in seconds and region of blood flow (RBF). Qontrast-assisted CEUS parameters displayed high inter-observer reproducibility (κ coefficients of 0.87 for MTT and 0.90 TTP). When the region of interest included a main hepatic vein, Qontrast-calculated TTP was significantly shorter in cirrhotic patients (vs non-cirrhotics and healthy subjects) (71.0 ± 11.3 s vs. 82.4 ± 15.6 s, 86.3 ± 20.3 s, P < 0.05). MTTs in the patients with liver cirrhosis were significantly shorter than those of controls (111.9 ± 22.0 s vs. 139.4 ± 39.8 s, P < 0.05), but there was no significant difference between the cirrhotic and non-cirrhotic groups (111.9 ± 22.0 s vs. 110.3 ± 14.6 s). Peak enhancement in the patients with liver cirrhosis was also higher than that observed in controls (23.9 ± 5.9 vs. 18.9 ± 7.1, P = 0.05). There were no significant intergroup differences in the RBVs and RBFs. Qontrast-assisted CEUS revealed reproducible differences in liver perfusion parameters during the development of hepatic fibrogenesis.

  4. Contrast-enhanced ultrasonography for the evaluation of liver fibrosis after biliary obstruction.

    Science.gov (United States)

    Shin, Hyun Joo; Chang, Eun Young; Lee, Hye Sun; Hong, Jung Hwa; Park, Gyuri; Kim, Hyun Gi; Kim, Myung-Joon; Lee, Mi-Jung

    2015-03-07

    To investigate perfusion change in contrast-enhanced ultrasonography (CEUS) to evaluate liver fibrosis based on biliary obstruction using an animal model. New Zealand white rabbits (3-4 kg) underwent bile duct ligation to form a biliary obstruction model. We performed liver CEUS and laboratory tests on the day before the operation (day 0) and every 7 postoperative days until the rabbits were sacrificed. After CEUS, signal intensity of liver parenchyma with a time-intensity curve was analyzed. Perfusion parameters were automatically calculated from region-of-interests, including peak signal intensity, mean transit time, area under the curve and time to peak. Histological grades of liver fibrosis were assessed according to the Metavir score system immediately after sacrifice. Generalized estimating equations were used to analyze the association between liver fibrosis grades and perfusion parameters for statistical analysis. The perfusion parameters were measured on the last day and the difference between day 0 and the last day were evaluated. From the nine rabbits, histological grades of liver fibrosis were grade 1 in one rabbit, grade 2 and 3 in three rabbits each, and grade 4 in two rabbits. Among the four CEUS parameters, only the peak signal intensity measured on the last day demonstrated a significant association with liver fibrosis grades (OR = 1.392, 95%CI: 1.114-1.741, P = 0.004). The difference in peak signal intensity between day 0 and the last day also demonstrated an association with liver fibrosis (OR = 1.191, 95%CI: 0.999-1.419, P = 0.051). The other parameters tested, including mean transit time, area under the curve, and time to peak, showed no significant correlation with liver fibrosis grades. This animal study demonstrates that CEUS can be used to evaluate liver fibrosis from biliary obstruction using peak signal intensity as a parameter.

  5. 3D contrast-enhanced MR portography and direct X-ray portography: a correlation study

    Energy Technology Data Exchange (ETDEWEB)

    Lin Jiang; Zhou Kangrong; Chen Zuang; Wang Jianhua; Yan Ziping [Department of Radiology, ZhongShan Hospital, Fudan University, Shanghai (China); Wang Yixiang J. [Department of Radiology, Rui Jin Hospital, Shanghai Second Medical Univeristy, Shanghai (China)

    2003-06-01

    Our objective was to compare 3D contrast-enhanced MR portography (3D CE MRP) on a 1.5-T MR imager with direct X-ray portography. Twenty-six consecutive patients underwent 3D CE MRP with in-plane resolution of 1.4 or 1.8 mm, and direct X-ray portography. The findings of these two methods were evaluated and compared. The main portal vein (PV), right PV with its anterior and posterior segmental branches, and left PV including its sagittal segment were shown clearly without diagnostic problem in all cases on MRP. The main PV appearance was accordant with MRP and X-ray. For intrahepatic PVs, the results agreed in 21 patients but disagreed in 5 patients. In 1 patient with a huge tumor in right liver, the right posterior PV was classified as occluded at MRP, but diffusely narrowed at X-ray. The findings of left intrahepatic PV were discordant in 3 patients with hepatocelluar carcinoma in the left lobe. The MRP demonstrated complete occlusion of the left PVs, whereas X-ray showed proximal narrowing and distal occlusion. In another patient with hepatocelluar carcinoma, a small non-occlusive thrombus involving the sagittal segment of the left PV was seen on MRP but not on X-ray. With demonstration of varices and portosystemic shunts, MRP showed results similar to those of X-ray, except one recanalized para-umbilical vein was excluded from the field of view at MRP due to the patient's limited ability of breathholding. The 3D CE MRP correlated well with direct X-ray portography in most cases, it was limited in distinguishing narrowing of an intrahepatic PV from occlusion, but it showed advantage in demonstrating small thrombus within PV. (orig.)

  6. The value of 3D contrasted-enhanced MR angiography in diagnosis of aortic dissection

    International Nuclear Information System (INIS)

    Liu Qi; Lu Jianping; Wang Fei; Wang Li; Tian Jianming; Jin Aiguo; Wang Jian

    2005-01-01

    Objective: To assess the value of three-dimensional contrast-enhanced MR angiography (3D CE-MRA) and its reconstruction in diagnosis of aortic dissection (AD). Methods: One hundred and thirty-six patients with AD underwent 3D CE-MRA with a 3D FLASH sequence after injection of 0.2 mmol Gd-DTPA per kg b. w. The source images were subtracted from mask images and transferred to computer workstation subsequently post-processed using volume rendering (VR), maximum intensity projection (MIP), multiplaner reformation (MPR) and virtual endoscopy (VE). Results: (1) Double lumen and intimal flap could be shown in all of 136 patients. There were 27 DeBakey type I dissections, 2 type II dissections and 107 type III dissections. Twenty-one cases were confirmed by surgery, and 32 cases, by DSA with endovascular graft exclusion. (2) Initial entry sites were defined in 105 cases. Compared with DSA, the depiction of 3D CE-MRA was 100% for initial entry sites and 91.4% for multi entry sites. Depiction of the initial entry sites was significantly better with VR and MPR, especially VR images. The shape, size and the relationship between the arterial orifice and the initial entry sites were clearly demonstrated with three-dimension on VR images, which was very helpful for surgery and endovascular graft exclusion. (3) The orifice of anonymous artery involved in type I dissections was 10 (10/27) , and the orifice of left subclavian artery involved in type III dissections, 10.3 percent. In 134 patients with type I and type III dissections, the kidney arterial orifice was involved in 32.1 percent; the celiac arterial orifice, 14.9 percent; the super mesenteric arterial orifice, 4.5 percent. Single artery involved was about 40.3 percent, and multi arteries, 12.7 percent

  7. Dynamic contrast-enhanced MRI of benign prostatic hyperplasia and prostatic carcinoma: correlation with angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Ren, J. [Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi' an (China); Huan, Y. [Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi' an (China)], E-mail: huanyi3000@163.com; Wang, H. [Department of Urology, Xijing Hospital, Fourth Military Medical University, Xi' an (China); Chang, Y.-J.; Zhao, H.-T.; Ge, Y.-L.; Liu, Y.; Yang, Y. [Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi' an (China)

    2008-02-15

    Aim: To investigate the diagnostic and differential diagnostic values of dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) in prostatic diseases, and to investigate the correlation between the parameters of SI-T curves and angiogenesis. Materials and methods: Twenty-one patients with proven prostatic carcinoma (Pca) and 29 patients with proven benign prostatic hyperplasia (BPH) were examined using DCE MRI. Diagnostic characteristics for differentiation were examined using threshold values for maximum peak time, enhancement degree, and enhancement rate. Then, the signal intensity-time curves (SI-T curves) were analysed, and the correlations between the parameters of SI-T curves and the expression levels of vascular endothelial growth factor (VEGF) and microvascular density (MVD) were investigated. All patients underwent prostatectomy. DCE MRI and histological findings were correlated. Results: Pca showed stronger enhancement with an earlier peak time, higher enhancement, and enhancement rate (p < 0.05). Regarding the type of SI-T curves, in the BPH group six were type A, 10 were type B, and 13 were type C, whereas in the Pca group, 14 were type A, six were type B, and only one was type C (Chi-square test, {chi}{sup 2} = 13.57, P < 0.005). The VEGF and MVD expression levels of Pca were higher than those of BPH. Peak time was negatively correlated with the expression levels of VEGF and MVD, whereas the enhancement degree and enhancement rate showed positive correlations (Pearson correlation, p < 0.05). Conclusion: Based on T2-weighted imaging, DCE MRI curves can help to differentiate benign from malignant prostate tissue. In the present study the type C curve was rarely seen with malignant disease, but these results need confirmation.

  8. Intravenous contrast enhanced computed tomography colonoscopy in children with suspected colonic polyps

    International Nuclear Information System (INIS)

    Bhatia, Anmol; Saxena, Akshay K.; Kalra, Naveen; Sodhi, Kushaljit S.; Thapa, Babu R.; Rao, Katragadda L.N.; Khandelwal, Niranjan

    2013-01-01

    Objective: The purpose of this study was to evaluate the diagnostic performance of intravenous contrast enhanced computed tomographic colonoscopy (IVCTC) in the diagnosis of clinically suspected colorectal polyps in children, using conventional colonoscopy (CC) as the gold standard. Methods: This was a prospective study conducted between July 2008 and June 2010. 30 pediatric patients with history of rectal bleeding and clinically suspected to have colorectal polyps were enrolled. All of the patients underwent IVCTC followed by CC. 30 IVCTC and 31 CC were performed in 30 patients. The findings of IVCTC were compared with those of CC. Statistical analysis was performed to obtain diagnostic performance values of IVCTC on per polyp (sensitivity and positive predictive value) and per patient (sensitivity, specificity, positive predictive value and negative predictive value) basis. Results: By IVCTC, 63 polyps were detected in 28 patients of which 53 polyps were eligible for inclusion in the statistical analysis. 60 polyps were detected by CC in 28 patients of which 50 polyps were eligible for inclusion in the statistical analysis. The per polyp sensitivity and positive predictive values were 94% and 88.6% respectively. The per patient sensitivity, specificity, positive predictive value, and negative predictive values were 96.4, 50, 96.4, and 50% respectively. Twenty polyps, in 10 patients, were visualized only after intravenous contrast administration of which 5 polyps, in 5 patients, were likely to have been missed in the absence of the intravenous contrast injection as these polyps were submerged in fluid. Four patients would have had a false negative CTC examination if the intravenous contrast had not been injected; while in another patient, the number of polyps would have been underestimated. Conclusion: CTC is capable of serving as a safe and efficient non-invasive tool for evaluating children with clinically suspected colorectal polyps. Administration of

  9. Contrast-enhanced ultrasonographic spoke-wheel sign in hepatic focal nodular hyperplasia

    Energy Technology Data Exchange (ETDEWEB)

    Yen, Y.-H. [Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Kaohsiung 833, Taiwan (China); Wang, J.-H. [Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Kaohsiung 833, Taiwan (China)]. E-mail: wajing@adm.cgmh.org.tw; Lu, S.-N. [Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Kaohsiung 833, Taiwan (China); Chen, T.-Y. [Department of Radiology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China); Changchien, C.-S. [Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Kaohsiung 833, Taiwan (China); Chen, C.-H. [Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Kaohsiung 833, Taiwan (China); Hung, C.-H. [Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Kaohsiung 833, Taiwan (China); Lee, C.-M. [Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Kaohsiung 833, Taiwan (China)

    2006-12-15

    Background: To determine the utility of contrast-enhanced ultrasonography (CEUS) in assessing hepatic tumors with central feeding arteries found by color/power Doppler ultrasonograophy (CDUS/PDUS). Methods: We prospectively studied 37 hepatic tumors (34 patients), with a mean size of 2.9 cm and each having a central feeding artery, by CDUS/PDUS. The CEUS was performed with a galactose-based microbubble contrast agent. The detection of a spoke-wheel sign was interpreted as evidence of focal nodular hyperplasia (FNH). All patients underwent tumor biopsies or surgical resection. Results: CEUS showed a central feeding artery with a spoke-wheel sign in 36 tumors, including 34 FNHs and 2 hepatocellular carcinomas. The remaining tumor was demonstrated to be FNH despite the absence of a spoke-wheel sign as detected by CEUS. The sensitivity of the spoke-wheel sign or central scar for FNH was 97.1% (34/35), 40% (14/35), 28.6% (10/35), 50% (8/16) and 0% (0/15) for CEUS, CDUS/PDUS, dynamic computed tomography (CT) or magnetic resonance imaging (MRI), hepatic angiography and liver scintigraphy, respectively. The two hepatocellular carcinomas showed scirrhous changes histologically. Conclusions: CEUS is more sensitive than CDUS/PDUS, dynamic CT, MRI, hepatic angiography and liver scintigraphy in the detection of the spoke-wheel sign or central scar in FNH. Scirrhous hepatocellular carcinoma should be included in the differential diagnosis for liver tumors with spoke-wheel sign detected by CEUS.

  10. Contrast-enhanced ultrasonographic spoke-wheel sign in hepatic focal nodular hyperplasia

    International Nuclear Information System (INIS)

    Yen, Y.-H.; Wang, J.-H.; Lu, S.-N.; Chen, T.-Y.; Changchien, C.-S.; Chen, C.-H.; Hung, C.-H.; Lee, C.-M.

    2006-01-01

    Background: To determine the utility of contrast-enhanced ultrasonography (CEUS) in assessing hepatic tumors with central feeding arteries found by color/power Doppler ultrasonograophy (CDUS/PDUS). Methods: We prospectively studied 37 hepatic tumors (34 patients), with a mean size of 2.9 cm and each having a central feeding artery, by CDUS/PDUS. The CEUS was performed with a galactose-based microbubble contrast agent. The detection of a spoke-wheel sign was interpreted as evidence of focal nodular hyperplasia (FNH). All patients underwent tumor biopsies or surgical resection. Results: CEUS showed a central feeding artery with a spoke-wheel sign in 36 tumors, including 34 FNHs and 2 hepatocellular carcinomas. The remaining tumor was demonstrated to be FNH despite the absence of a spoke-wheel sign as detected by CEUS. The sensitivity of the spoke-wheel sign or central scar for FNH was 97.1% (34/35), 40% (14/35), 28.6% (10/35), 50% (8/16) and 0% (0/15) for CEUS, CDUS/PDUS, dynamic computed tomography (CT) or magnetic resonance imaging (MRI), hepatic angiography and liver scintigraphy, respectively. The two hepatocellular carcinomas showed scirrhous changes histologically. Conclusions: CEUS is more sensitive than CDUS/PDUS, dynamic CT, MRI, hepatic angiography and liver scintigraphy in the detection of the spoke-wheel sign or central scar in FNH. Scirrhous hepatocellular carcinoma should be included in the differential diagnosis for liver tumors with spoke-wheel sign detected by CEUS

  11. MRI of acute cerebral infarcts: increased contrast enhancement with continuous infusion of gadolinium

    International Nuclear Information System (INIS)

    Merten, C.L.; Assheuer, J.; Bergmann-Kurz, B.; Bewermeyer, H.; Knitelius, H.O.; Hedde, J.P.

    1999-01-01

    We compared contrast enhancement on T1-weighted MRI of acute cerebral infarcts after conventional bolus administration and continuous infusion of gadolinium. We examined 12 patients with a history of acute stroke with contrast-enhanced MRI once a week for a 1 month. Only ischaemic lesions were investigated after cerebral haemorrhage had been excluded by CT. Each MRI study included T2- and proton density-weighted sequences for determination of the size and site of the infarct, immediate postinjection T1-weighted imaging after bolus administration of 0.1 mmol/kg gadolinium-DPTA and delayed T1-weighted imaging after additional continuous infusion of 0.1 mmol/kg over 2 h. A total of 42 MRI studies was performed. In the first week after the onset of stroke, most infarcts (8 of 10) did not enhance after bolus administration, whereas all showed distinct contrast enhancement after the infusion. In the following weeks all but two infarcts showed contrast enhancement after bolus administration; after continuous infusion contrast enhancement could be seen in all cases. While contrast enhancement after bolus administration showed the typical gyriform pattern, enhanced areas were more extensive after the infusion and usually covered the entire infarcted area shown on T2- and proton density-weighted images. We presume that the disturbed blood-brain barrier in ischaemic areas favours delivery of contrast medium to the infarcted tissue if it is offered continuously so that a steady state can develop. (orig.)

  12. Gray-scale contrast-enhanced utrasonography in detecting sentinel lymph nodes: An animal study

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yuexiang, E-mail: wangyuexiang1999@sina.co [Department of Ultrasound, Chinese People' s Liberation Army General Hospital, 28 Fuxing Road, Beijing 100853 (China); Cheng Zhigang, E-mail: qlczg@sina.co [Department of Ultrasound, Chinese People' s Liberation Army General Hospital, 28 Fuxing Road, Beijing 100853 (China); Li Junlai, E-mail: junlai555@sina.co [Department of Ultrasound, Chinese People' s Liberation Army General Hospital, 28 Fuxing Road, Beijing 100853 (China); Tang Jie, E-mail: txiner@vip.sina.co [Department of Ultrasound, Chinese People' s Liberation Army General Hospital, 28 Fuxing Road, Beijing 100853 (China)

    2010-06-15

    Objective: To investigate the usefulness of gray-scale contrast-enhanced ultrasonography for detecting sentinel lymph nodes. Methods: Contrast-enhanced ultrasonography was performed in five normal dogs (four female and one male) after subcutaneous administration of a sonographic contrast agent (Sonovue, Bracco, Milan, Italy). Four distinct regions in each animal were examined. After contrast-enhanced ultrasonography, 0.8 ml of blue dye was injected into the same location as Sonovue and the sentinel lymph nodes were detected by surgical dissection. The findings of contrast-enhanced ultrasonography were compared with those of the blue dye. Results: Twenty-one sentinel lymph nodes were detected by contrast-enhanced ultrasonography while 23 were identified by blue dye with surgical dissection. Compared with the blue dye, the detection rate of enhanced ultrasonography for the sentinel lymph nodes is 91.3% (21/23). Two patterns of enhancement in the sentinel lymph nodes were observed: complete enhancement (5 sentinel lymph nodes) and partial enhancement (16 sentinel lymph nodes). The lymphatic channels were demonstrated as hyperechoic linear structures leading from the injection site and could be readily followed to their sentinel lymph nodes. Histopathologic examination showed proliferation of lymphatic follicles or lymphatic sinus in partial enhanced sentinel lymph nodes while normal lymphatic tissue was demonstrated in completely enhanced sentinel lymph nodes. Conclusions: Sonovue combined with gray-scale contrast-enhanced ultrasonography may provide a feasible method for detecting sentinel lymph nodes.

  13. Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

    International Nuclear Information System (INIS)

    Nakamura, T.; Naganawa, S.; Fukatsu, H.; Sakurai, Y.; Ishigaki, T.; Aoki, I.; Ninomiya, A.; Nakashima, T.

    2003-01-01

    There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion. (orig.)

  14. Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T.; Naganawa, S.; Fukatsu, H.; Sakurai, Y.; Ishigaki, T. [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, 466-8550, Shouwa-ku, Nagoya (Japan); Aoki, I.; Ninomiya, A. [Medical Systems Company, Toshiba Corporation, Nasu Operations, Otawara-shi, Tochigi (Japan); Nakashima, T. [Department of Otorhinolaryngology, Nagoya University School of Medicine, Shouwa-ku, Nagoya (Japan)

    2003-09-01

    There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion. (orig.)

  15. Contrast enhanced MR imaging of female pelvic cancers: Established methods and emerging applications

    Energy Technology Data Exchange (ETDEWEB)

    Punwani, Shonit, E-mail: shonit.punwani@gmail.com [Department of Academic Radiology, 2nd Floor Podium, University College London Hospital, 235 Euston Road, London NW1 2BU (United Kingdom)

    2011-04-15

    Contrast enhanced magnetic resonance imaging of female pelvic cancers has been established for over 20 years. Conventional contrast enhanced imaging involves acquiring a set of pre-contrast T1 weighted images, followed by intravenous injection of an gadolinium based contrast agent and subsequent acquisition of a second set of contrast enhanced images. Developments in MR hardware and pulse sequences over the last 10 years have made dynamic contrast enhanced (DCE) protocols possible. DCE-MRI entails imaging of the same volume repeatedly prior to, during and following contrast injection. There have also been developments in image analysis methods and tools to reflect the increased data acquired. Qualitative analysis of contrast enhanced imaging (whether a single set or temporal series) by radiologists remains the mainstay for clinical reporting. Semi-quantitative assessment of signal intensity versus time curves and full pharmacokinetic modelling methods have emerged for evaluation of DCE-MRI data. DCE-MRI has found an established role in the detection, localisation and staging of female pelvic malignancies. Emerging applications of DCE-MRI include assessment of tumour grade, histology prior to and following treatment and prediction of individual and final treatment outcome. This article reviews the biophysical basis of contrast enhancement, the technical aspects of performance and analysis of DCE-MRI studies, and the established and emerging clinical utility of DCE-MRI in female pelvic malignancies.

  16. Application of contrast-enhanced helical hydro-CT in diagnosing and staging gastric cancer

    International Nuclear Information System (INIS)

    Wei Wenzhou; Yu Jieping; Li Jun; Liu Changsheng; Zheng Xiaohua

    2006-01-01

    Objective: To explore helical CT characteristics of gastric cancer and evaluate the diagnostic value of contrast-enhanced helical hydro-CT(HHCT)in staging gastric cancer. Methods: The CT images of S0 patients with gastric cancer were retrospectively analyzed and correlated with pathologic findings at surgery. All patients were preoperatively imaged by plain and contrast-enhanced HHCT 30 rain after drinking S00-1000 ml water. Peristalsis was minimized by intravenously administered spasmolytics. Results: The characteristic findings of gastric carcer on CT images were focal or diffuse mural thickening, soft tissue masses, cancerous ulcers, stenosis of stomach, infiltration to adjacent tissues, lymph node metastasis and distant metastases. Strong contrast enhancement of the gastric wall was firmly related to gastric carcer. The foci of gastric carcer mainly located at the gastric cardia and gastric antrum, and became more prominent in contrast-enhanced HHCT than in plain HHCT.The accurate rate of contrast-enhanced HHCT for staging gastric carcer was 86% (43/50), and the detection rate of lymph node metastases by CT was 60% (12/20). Conclusion: Contrast-enhanced HHCT is a reliable method for diagnosing and staging gastric carcer. It is a useful guide for surgeons to plan the best treatment for patients with gastric cancer. (authors)

  17. Gray-scale contrast-enhanced utrasonography in detecting sentinel lymph nodes: An animal study

    International Nuclear Information System (INIS)

    Wang Yuexiang; Cheng Zhigang; Li Junlai; Tang Jie

    2010-01-01

    Objective: To investigate the usefulness of gray-scale contrast-enhanced ultrasonography for detecting sentinel lymph nodes. Methods: Contrast-enhanced ultrasonography was performed in five normal dogs (four female and one male) after subcutaneous administration of a sonographic contrast agent (Sonovue, Bracco, Milan, Italy). Four distinct regions in each animal were examined. After contrast-enhanced ultrasonography, 0.8 ml of blue dye was injected into the same location as Sonovue and the sentinel lymph nodes were detected by surgical dissection. The findings of contrast-enhanced ultrasonography were compared with those of the blue dye. Results: Twenty-one sentinel lymph nodes were detected by contrast-enhanced ultrasonography while 23 were identified by blue dye with surgical dissection. Compared with the blue dye, the detection rate of enhanced ultrasonography for the sentinel lymph nodes is 91.3% (21/23). Two patterns of enhancement in the sentinel lymph nodes were observed: complete enhancement (5 sentinel lymph nodes) and partial enhancement (16 sentinel lymph nodes). The lymphatic channels were demonstrated as hyperechoic linear structures leading from the injection site and could be readily followed to their sentinel lymph nodes. Histopathologic examination showed proliferation of lymphatic follicles or lymphatic sinus in partial enhanced sentinel lymph nodes while normal lymphatic tissue was demonstrated in completely enhanced sentinel lymph nodes. Conclusions: Sonovue combined with gray-scale contrast-enhanced ultrasonography may provide a feasible method for detecting sentinel lymph nodes.

  18. Contrast-enhanced FLAIR (fluid-attenuated inversion recovery for evaluating mild traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Soo Chin Kim

    Full Text Available PURPOSE: To evaluate whether adding a contrast-enhanced fluid-attenuated inversion recovery (FLAIR sequence to routine magnetic resonance imaging (MRI can detect additional abnormalities in the brains of symptomatic patients with mild traumatic brain injury. MATERIALS AND METHODS: Fifty-four patients with persistent symptoms following mild closed head injury were included in our retrospective study (M ∶ F =  32 ∶ 22, mean age: 59.8 ± 16.4, age range: 26-84 years. All MRI examinations were obtained within 14 days after head trauma (mean: 3.2 ± 4.1 days, range: 0.2-14 days. Two neuroradiologists recorded (1 the presence of traumatic brain lesions on MR images with and without contrast-enhanced FLAIR images and (2 the pattern and location of meningeal enhancement depicted on contrast-enhanced FLAIR images. The number of additional traumatic brain lesions diagnosed with contrast-enhanced FLAIR was recorded. Correlations between meningeal enhancement and clinical findings were also evaluated. RESULTS: Traumatic brain lesions were detected on routine image sequences in 25 patients. Three additional cases of brain abnormality were detected with the contrast-enhanced FLAIR images. Meningeal enhancement was identified on contrast-enhanced FLAIR images in 9 cases while the other routine image sequences showed no findings of traumatic brain injury. Overall, the additional contrast-enhanced FLAIR images revealed more extensive abnormalities than routine imaging in 37 cases (p<0.001. In multivariate logistic regression analysis, subdural hematoma and posttraumatic loss of consciousness showed a significant association with meningeal enhancement on contrast-enhanced FLAIR images, with odds ratios 13.068 (95% confidence interval 2.037 to 83.852, and 15.487 (95% confidence interval 2.545 to 94.228, respectively. CONCLUSION: Meningeal enhancement on contrast-enhanced FLAIR images can help detect traumatic brain lesions as well as additional abnormalities

  19. Role of contrast-enhanced MR venography in the preoperative evaluation of parasagittal meningiomas

    International Nuclear Information System (INIS)

    Bozzao, Alessandro; Finocchi, Vanina; Romano, Andrea; Ferrante, Michele; Fasoli, Fabrizio; Fantozzi, Luigi Maria; Trillo, Giuseppe; Ferrante, Luigi

    2005-01-01

    Parasagittal meningiomas (PSM) may pose a difficult surgical challenge since venous patency and collateral anastomoses have to be clearly defined for correct surgical planning. The aim of this study was to assess the diagnostic value of contrast-enhanced (CE) magnetic resonance venography (MRV) in the preoperative evaluation of venous infiltration and collateral venous anastomoses in patients with PSM. CE-MRV was compared with phase-contrast (PC) magnetic resonance (MR) angiography, conventional angiography (when available), and surgery as a reference. Twenty-three patients undergoing surgery for meningiomas located adjacent to the superior sagittal sinus were prospectively evaluated. All the patients underwent both conventional MR examination and MRV. This was performed by means of PC and CE techniques. Both sets of angiograms (CE and PC) were evaluated by two expert neuroradiologists to assess (1) patency of the sinus (patent/occluded), (2) the extent of occlusion (in centimeters), and (3) the number of collateral anastomoses close to the insertion of the meningioma. Eight patients underwent digital subtraction angiography (DSA). All patients were operated on, and intraoperative findings were taken as the gold standard to evaluate the diagnostic value of MRA techniques. PC-MRV showed a flow void inside the sinus compatible with its occlusion in 15 cases, whereas CE-MRV showed the sinus to be occluded in five cases. CE-MRV data were confirmed by surgery, showing five patients to have an occlusion of the superior sagittal sinus. The PC-MRV sensitivity was thus 100% with a specificity of 50%. In those cases in which both MRV techniques documented occlusion of the sinus, the extent of occlusion was overestimated by PC compared with CE and surgery. CE-MRV depicted 87% of collateral venous anastomoses close to the meningioma as subsequently confirmed by surgery, while PC showed 58%. In the preoperative planning for patients with meningiomas located close to a venous

  20. Can contrast-enhanced ultrasonography replace multidetector-computed tomography in the detection of liver metastases from colorectal cancer?

    DEFF Research Database (Denmark)

    Larsen, Lars P.S.; Rosenkilde, Mona; Christensen, Henrik

    2007-01-01

    PURPOSE: To compare the sensitivity and specificity of contrast-enhanced ultrasonography (CEUS) and 4-slice multidetector-computed tomography (MDCT) in the detection of liver metastases in patients with colorectal cancer (CRC). MATERIALS AND METHODS: Candidates for this prospective study were 461...... consecutive patients referred to the Department of Colorectal Surgery, Aarhus University Hospital with primary or local recurrence of CRC. The patients underwent liver ultrasonography (US), CEUS, MDCT and intraoperative ultrasonography (IOUS). Fine-needle biopsy was performed on all suspicious lesions...... liver metastases in 54 patients (14.8%). Multidetector CT found significantly more metastases than CEUS in 15 (28%) of the patients (p=0.02). In a patient-by-patient analysis MDCT had a non-significantly higher sensitivity in the detection of liver metastases compared to CEUS (0.89 versus 0.80, p=0...

  1. Therapeutic response assessment of high intensity focused ultrasound therapy for uterine fibroid: Utility of contrast-enhanced ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Xiaodong [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)]. E-mail: zhouxd@fmmu.edu.cn; Ren Xiaolong [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)]. E-mail: renxiaolong70@hotmail.com; Zhang Jun [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); He Guangbin [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zheng Minjuan [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Tian Xue [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Li Li [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zhu Ting [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zhang Min [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Wang Lei [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Luo Wen [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)

    2007-05-15

    Purpose: To assess the utility of contrast-enhanced ultrasonography (ceUS) in the assessment of the therapeutic response to high intensity focused ultrasound (HIFU) ablation in patients with uterine fibroid. Materials and methods: Sixty-four patients with a total of 64 uterine fibroids (mean: 5.3 {+-} 1.2 cm; range: 3.2-8.9 cm) treated with HIFU ablation under the ultrasound guidance were evaluated with ceUS after receiving an intravenous bolus injection of a microbubble contrast agent (SonoVue) within 1 week after intervention. We obtained serial ceUS images during the time period from beginning to 5 min after the initiation of the bolus contrast injection. All of the patients underwent a contrast enhanced MRI (ceMRI) and ultrasound guided needle puncture biopsy within 1 week after HIFU ablation. And as a follow-up, all of the patients underwent US at 1, 3, 6 and 12 months after HIFU treatment. The volume change was observed and compared to pre- and post-HIFU ablation. The results of the ceUS were compared with those of the ceMRI in terms of the presence or absence of residual unablated tumor and pathologic change in the treated lesions. Results: On ceUS, diagnostic accuracy was 100%, while residual unablated tumors were found in three uterine fibroids (4.7%) and failed treatment was found in eight uterine fibroids (12.5%). All the 11 fibroids were subjected to additional HIFU ablation. Of the 58 ablated fibroids without residual tumors on both the ceUS and ceMRI after the HIFU ablation, the volumes of all the fibroids decreased in different degrees during the 1 year follow-up USs. And histologic examinations confirmed findings of necrotic and viable tumor tissue, respectively. Conclusion: CEUS is potentially useful for evaluating the early therapeutic effect of percutaneous HIFU ablation for uterine fibroids.

  2. Therapeutic response assessment of high intensity focused ultrasound therapy for uterine fibroid: Utility of contrast-enhanced ultrasonography

    International Nuclear Information System (INIS)

    Zhou Xiaodong; Ren Xiaolong; Zhang Jun; He Guangbin; Zheng Minjuan; Tian Xue; Li Li; Zhu Ting; Zhang Min; Wang Lei; Luo Wen

    2007-01-01

    Purpose: To assess the utility of contrast-enhanced ultrasonography (ceUS) in the assessment of the therapeutic response to high intensity focused ultrasound (HIFU) ablation in patients with uterine fibroid. Materials and methods: Sixty-four patients with a total of 64 uterine fibroids (mean: 5.3 ± 1.2 cm; range: 3.2-8.9 cm) treated with HIFU ablation under the ultrasound guidance were evaluated with ceUS after receiving an intravenous bolus injection of a microbubble contrast agent (SonoVue) within 1 week after intervention. We obtained serial ceUS images during the time period from beginning to 5 min after the initiation of the bolus contrast injection. All of the patients underwent a contrast enhanced MRI (ceMRI) and ultrasound guided needle puncture biopsy within 1 week after HIFU ablation. And as a follow-up, all of the patients underwent US at 1, 3, 6 and 12 months after HIFU treatment. The volume change was observed and compared to pre- and post-HIFU ablation. The results of the ceUS were compared with those of the ceMRI in terms of the presence or absence of residual unablated tumor and pathologic change in the treated lesions. Results: On ceUS, diagnostic accuracy was 100%, while residual unablated tumors were found in three uterine fibroids (4.7%) and failed treatment was found in eight uterine fibroids (12.5%). All the 11 fibroids were subjected to additional HIFU ablation. Of the 58 ablated fibroids without residual tumors on both the ceUS and ceMRI after the HIFU ablation, the volumes of all the fibroids decreased in different degrees during the 1 year follow-up USs. And histologic examinations confirmed findings of necrotic and viable tumor tissue, respectively. Conclusion: CEUS is potentially useful for evaluating the early therapeutic effect of percutaneous HIFU ablation for uterine fibroids

  3. Contrast-enhanced ultrasound-guided radiofrequency ablation in inconspicuous hepatocellular carcinoma on B-mode ultrasound.

    Science.gov (United States)

    Kim, Eui Joo; Kim, Yun Soo; Shin, Seung Kak; Kwon, Oh Sang; Choi, Duck Joo; Kim, Ju Hyun

    2017-11-01

    B-mode ultrasound (US) has difficulty targeting small hepatocellular carcinomas (HCCs) with poor conspicuity during radiofrequency ablation (RFA). Contrast-enhanced ultrasound (CEUS) can improve visualization of small or inconspicuous HCCs. This study was conducted to evaluate the effectiveness of CEUS-guided RFA electrode insertion during the arterial phase in inconspicuous HCCs. Ninety-three treatment-naïve HCCs from 80 patients treated with RFA from August 2012 to December 2014 were retrospectively reviewed. Seventy-five HCCs from 65 patients underwent B-mode US-guided RFA, and 15 HCCs from 14 patients that were inconspicuous on B-mode US underwent CEUS-guided RFA during the arterial phase after injection of sulfur hexafluoride microbubbles (SonoVue®). Technical success was assessed by contrast-enhanced computed tomography within 1 week and 3 months after the procedure. The mean size of HCCs treated with CEUS-guided RFA was smaller than that of HCCs treated with B-mode US-guided RFA (1.17±0.36 vs. 1.63±0.55 cm, p=0.003). Technical success rates of CEUS-guided RFA within 1 week and 3 months were 100% (15/15) and 93.3% (14/15), respectively. Technical success rates of B-mode US-guided RFA were 97.3% (73/75) and 94.5% (69/73), respectively. CEUS-guided RFA is highly efficacious for ablation of very small and inconspicuous HCCs.

  4. 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

  5. The Effect of the Degree of Luminal Contrast-Enhancement on CT Measurement of Plaque Size: A Comparison with T1-weighted Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    Choi, Byoung Wook; Hur, Jin; Lee, Hye Jeong; Kim, Young Jin; Choe, Kyu Ok; Kim, Tae Hoon

    2010-01-01

    We studied early and delayed contrast-enhanced CT to determine the effects of the degree of luminal enhancement on the measurement of plaque size compared to T1-weighted MRI. T1-weighted MRI and a two-phase contrast-enhanced CT was performed in 5 New Zealand white rabbits with atherosclerosis. Early-phase images were acquired during an expected peak enhancement period of the lumen; delayed-phase images were acquired 240 sec after administration of the contrast media. Anteroposterior and lateral luminal diameters (APD, LD), luminal area (LA), total vessel area (TVA), and plaque area (PA) of the aorta were measured on MRI and CT, respectively and compared to each other. A total of 78 slices of the aorta were analyzed. PA, measured on T1-weighted MR images, was significantly greater than PA for both early-phase and delayed-phase CT (p 2 (p 2 (p 2 (p = 0.159) for MRI vs. early-phase CT, MRI vs. delayed-phase CT, and early-phase CT vs. delayed-phase CT, respectively. Different luminal densities by contrast enhancement do not affect the CT measurement of plaque area for the detection of obstructive coronary artery disease

  6. The role of contrast-enhanced ultrasound in planning treatment protocols for hepatocellular carcinoma before radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, M.H. [Ultrasound Department, School of Oncology, Peking University, Hai Dian District, Beijing 100036 (China)]. E-mail: minhuachen@vip.sina.com; Yang, W. [Ultrasound Department, School of Oncology, Peking University, Hai Dian District, Beijing 100036 (China); Yan, K. [Ultrasound Department, School of Oncology, Peking University, Hai Dian District, Beijing 100036 (China); Dai, Y. [Ultrasound Department, School of Oncology, Peking University, Hai Dian District, Beijing 100036 (China); Wu, W. [Ultrasound Department, School of Oncology, Peking University, Hai Dian District, Beijing 100036 (China); Fan, Z.H. [Ultrasound Department, School of Oncology, Peking University, Hai Dian District, Beijing 100036 (China); Callstrom, M.R. [Mayo Clinic College of Medicine, Rochester, MN 55905 (United States); Charboneau, J.W. [Mayo Clinic College of Medicine, Rochester, MN 55905 (United States)

    2007-08-15

    Aim: To evaluate the clinical value of contrast-enhanced ultrasound (CEUS) for patients with hepatocellular carcinoma (HCC) in identifying the tumour number, ablation range and feeding vessels before ultrasound-guided radiofrequency ablation (RFA), and to compare the efficacy of RFA after CEUS with the efficacy of RFA after non-enhanced ultrasonography (US) without contrast medium administration. Materials and methods: From 2002 to 2005, 81 patients with 110 HCCs underwent CEUS with SonoVue before RFA treatment (group A). Eighty six patients with 112 HCCs who underwent US without contrast enhancement before RFA served as the control group (group B). The average diameters of the lesions in group A and group B were 3.6 {+-} 1.1 cm and 3.5 {+-} 1.1 cm, respectively. There were no significant differences in clinical data between the two groups. Regular follow-up after treatment was performed using contrast-enhanced computed tomography (CECT). After treatment, complete necrosis was defined as the absence of viable tissue in treated tumours at the 1-year follow-up CECT. Results: Using CEUS an additional seven small lesions ({<=}2.0 cm) were found compared with those found using CECT and conventional US. CEUS showed that 56.4% of lesions (62/110 tumours) were larger in size and 49.1% (54/110 tumours) became more irregular in shape during the arterial phase than on conventional US. Feeding vessels were detected using CEUS in 52 (91.2%) of 57 lesions that were larger than 3.5 cm. The follow-up period was at least 1 year for each case. The complete tumour necrosis rate in group A was significantly higher than that in group B (92.2% versus 83.0%; p = 0.036). Conclusion: CEUS can be used to more accurately define the size and contour of lesions, and to detect additional small or satellite lesions and the feeding vessel of HCC tumours. CEUS provided important information for designing the ablation protocol, and might improve the efficacy of RFA.

  7. Contrast-enhanced computed tomography for the diagnosis of fatty liver: prospective study with same-day biopsy used as the reference standard

    International Nuclear Information System (INIS)

    Kim, Dae Yoon; Park, Seong Ho; Lee, Seung Soo; Kim, Hye Jin; Kim, So Yeon; Kim, Min-Young; Lee, Yedaun; Kim, Tae Kyoung; Khalili, Korosh; Bae, Mi Hyun; Lee, Joo Yeon; Lee, Sung-Gyu; Yu, Eun Sil

    2010-01-01

    Purpose: The study purpose was to prospectively determine the accuracy of contrast-enhanced CT in diagnosing fatty liver using same-day biopsy as the reference standard. One hundred seventy-nine potential living liver donors underwent unenhanced and portal-phase contrast-enhanced hepatic CT and subsequent liver biopsy on the same day. Attenuation difference between the liver and the spleen on unenhanced ( pre L-S) and contrast-enhanced ( post L-S) images and blood-subtracted hepatic attenuation on contrast-enhanced images ( post L-B), calculated by [L - 0.3 x (0.75 x P + 0.25 x A) ]/0.7 where L, P and A represent the attenuation of the liver, main portal vein and abdominal aorta, respectively, were obtained. The accuracy of these indices in diagnosing fatty liver according to various threshold levels, 5%-30% histological steatosis in increments of 5%, was compared using ROC analysis. The area under the ROC curve for pre L-S, post L-S and post L-B was 0.663-0.918, 0.712-0.847 and 0.821-0.923, respectively, depending on the threshold levels of hepatic steatosis. The accuracy of pre L-S and post L-S did not differ (P ≥ 0.054), despite a trend towards a lower accuracy with post L-S. post L-B yielded higher accuracy than pre L-S at threshold levels of 5% and 10% (P ≤ 0.002) and similar accuracy to pre L-S at the other threshold levels (P ≥ 0.144). Portal-phase contrast-enhanced CT has a similar, or even greater, accuracy than unenhanced CT in diagnosing fatty liver. (orig.)

  8. The added value of {sup 68}Ga-DOTA-TATE-PET to contrast-enhanced CT for primary site detection in CUP of neuroendocrine origin

    Energy Technology Data Exchange (ETDEWEB)

    Kazmierczak, Philipp M. [Klinikum der Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany); Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Muenchen (Germany); Rominger, Axel; Wenter, Vera [Ludwig-Maximilians-University Hospital Munich, Department of Nuclear Medicine, Muenchen (Germany); Spitzweg, Christine; Auernhammer, Christoph [Ludwig-Maximilians-University Hospital Munich, Department of Internal Medicine II, Muenchen (Germany); Angele, Martin K. [Ludwig-Maximilians-University Hospital Munich, Department of General, Visceral, Transplantation, Vascular and Thoracic Surgery, Muenchen (Germany); Rist, Carsten; Cyran, Clemens C. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Muenchen (Germany)

    2017-04-15

    To quantify the additional value of {sup 68}Ga-DOTA-TATE PET/CT in comparison with contrast-enhanced CT alone for primary tumour detection in neuroendocrine cancer of unknown primary (CUP-NET). In total, 38 consecutive patients (27 men, 11 women; mean age 62 years) with histologically proven CUP-NET who underwent a contrast-enhanced {sup 68}Ga-DOTA-TATE PET/CT scan for primary tumour detection and staging between 2010 and 2014 were included in this IRB-approved retrospective study. Two blinded readers independently analysed the contrast-enhanced CT and {sup 68}Ga-DOTA-TATE PET datasets separately and noted from which modality they suspected a primary tumour. Consensus was reached if the results were divergent. Postoperative histopathology (24 patients) and follow-up {sup 68}Ga-DOTA-TATE PET/CT imaging (14 patients) served as the reference standards and statistical measures of diagnostic accuracy were calculated accordingly. The majority of confirmed primary tumours were located in the abdomen (ileum in 19 patients, pancreas in 12, lung in 2, small pelvis in 1). High interobserver agreement was noted regarding the suspected primary tumour site (Cohen's k 0.90, p < 0.001). {sup 68}Ga-DOTA-TATE PET demonstrated a significantly higher sensitivity (94 % vs. 63 %, p = 0.005) and a significantly higher accuracy (87 % vs. 68 %, p = 0.003) than contrast-enhanced CT. Ga-DOTA-TATE PET/CT compared with contrast-enhanced CT alone provides an improvement in sensitivity of 50 % and an improvement in accuracy of 30 % in primary tumour detection in CUP-NET. (orig.)

  9. Baseline incidence and severity of renal insufficiency evaluated by estimated glomerular filtration rates in patients scheduled for contrast-enhanced CT

    International Nuclear Information System (INIS)

    Utsunomiya, Daisuke; Yanaga, Yumi; Oda, Seitaro; Namimoto, Tomohiro; Yamashita, Yasuyuki; Awai, Kazuo; Funama, Yoshinori

    2011-01-01

    Background Although pre-existing renal insufficiency (RI) is the most important risk factor for contrast-induced nephropathy (CIN), the background distribution of baseline renal function has not been investigated thoroughly in patients scheduled for contrast-enhanced CT. Purpose To investigate the incidence and severity of baseline RI evaluated by estimated glomerular filtration rates (eGFR) in patients who underwent contrast-enhanced CT at an academic center. Material and Methods A total of 6586 patients (3630 men and 2956 women; mean age 57.0 ± 11.9 years) who underwent contrast-enhanced CT between January and December 2008 were retrospectively studied. Of these, 829 had cardiovascular diseases (CVD), 5116 had oncologic diseases, 178 had diabetes mellitus (DM), and 1572 had chronic liver disease (CLD). The eGFR (mL/min/1.73 m 2 ) was calculated from their serum creatinine level. Mild, moderate-a, moderate-b, and severe RI were recorded at 60 2 at baseline was high in patients with advanced age, CVD and DM and in patients without oncologic disease

  10. Determination of contrast media administration to achieve a targeted contrast enhancement in CT

    Science.gov (United States)

    Sahbaee, Pooyan; Li, Yuan; Segars, Paul; Marin, Daniele; Nelson, Rendon; Samei, Ehsan

    2015-03-01

    Contrast enhancement is a key component of CT imaging and offer opportunities for optimization. The design and optimization of new techniques however requires orchestration with the scan parameters and further a methodology to relate contrast enhancement and injection function. In this study, we used such a methodology to develop a method, analytical inverse method, to predict the required injection function to achieve a desired contrast enhancement in a given organ by incorporation of a physiologically based compartmental model. The method was evaluated across 32 different target contrast enhancement functions for aorta, kidney, stomach, small intestine, and liver. The results exhibited that the analytical inverse method offers accurate performance with error in the range of 10% deviation between the predicted and desired organ enhancement curves. However, this method is incapable of predicting the injection function based on the liver enhancement. The findings of this study can be useful in optimizing contrast medium injection function as well as the scan timing to provide more consistency in the way that the contrast enhanced CT examinations are performed. To our knowledge, this work is one of the first attempts to predict the contrast material injection function for a desired organ enhancement curve.

  11. A comparative study on preprocessing techniques in diabetic retinopathy retinal images: illumination correction and contrast enhancement.

    Science.gov (United States)

    Rasta, Seyed Hossein; Partovi, Mahsa Eisazadeh; Seyedarabi, Hadi; Javadzadeh, Alireza

    2015-01-01

    To investigate the effect of preprocessing techniques including contrast enhancement and illumination correction on retinal image quality, a comparative study was carried out. We studied and implemented a few illumination correction and contrast enhancement techniques on color retinal images to find out the best technique for optimum image enhancement. To compare and choose the best illumination correction technique we analyzed the corrected red and green components of color retinal images statistically and visually. The two contrast enhancement techniques were analyzed using a vessel segmentation algorithm by calculating the sensitivity and specificity. The statistical evaluation of the illumination correction techniques were carried out by calculating the coefficients of variation. The dividing method using the median filter to estimate background illumination showed the lowest Coefficients of variations in the red component. The quotient and homomorphic filtering methods after the dividing method presented good results based on their low Coefficients of variations. The contrast limited adaptive histogram equalization increased the sensitivity of the vessel segmentation algorithm up to 5% in the same amount of accuracy. The contrast limited adaptive histogram equalization technique has a higher sensitivity than the polynomial transformation operator as a contrast enhancement technique for vessel segmentation. Three techniques including the dividing method using the median filter to estimate background, quotient based and homomorphic filtering were found as the effective illumination correction techniques based on a statistical evaluation. Applying the local contrast enhancement technique, such as CLAHE, for fundus images presented good potentials in enhancing the vasculature segmentation.

  12. Analysis of peritumoral edema and contrast enhancement by computerized axial tomography

    International Nuclear Information System (INIS)

    Oi, Shizuo; Szper, I.; Wetzel, N.; Kim, Kwang-S.

    1980-01-01

    For the purpose of treating brain tumors satisfactorily with steroids, CT findings of brain tumors were analyzed, and pathogenesis of peritumoral edema and supposed effects of steroids were investigated. The degree of peritumoral edema and contrast enhancement and their relationship were analyzed in total 201 patients with brain tumors (gliomas, meningiomas, and metastatic brain tumors). As a result, significant peritumoral edema was recognized in 59% of patients with metastatic brain tumors, 46% of patients with glioma, and 34% of patients with meningioma. As a rule, there was a relationship between peritumoral edema and malignancy or localization of braiin tumors. Severe peritumoral edema was observed in malignant supratentorial tumors (over 60%), but peritumoral edema which was found in infratentorial tumors benign gliomas was mild. The degree of contrast enhancement differed according to tumors, and there was not always a relationship between the degree of contrast enhancement and malignancy or localization of brain tumors. CT findings of brain tumors after the administration of steroids showed decrease in the degree of contrast enhancement. Judging from the effect of steroids to inhibit increased vascular permeability associated with brain edema, like CT findings of peritumoral edema, the degree of contrast enhancement which probably expressed vascularity or vascular permeability seemed to be important in deciding the indications for steroid administration. (Tsunoda, M.)

  13. The analysis of the contrast enhanced lesions on cerebro-vascular diseases

    International Nuclear Information System (INIS)

    Terada, Tomoaki; Nishiguchi, Takashi; Hyoutani, Genhachi; Miyamoto, Kazuki; Komai, Norihiko

    1989-01-01

    The contrast enhancement of cerebro-vascular diseases on CT is thought to be due to the increase of the cerebral blood volume (CBV) and/or the disruption of the blood brain barrier (BBB). However, it is difficult to differentiate these two conditions only by contrast enhanced CT. We employed dynamic CT (DCT) to analyse these lesions with respect to the patterns of time-density curve and peak height (PH) of the curve upon the theoretical basis that flattening of the latter part of the time-density curve reflected the degree of BBB disruption and PH reflected the CBV. In all cases of hypertensive intracerebral hemorrhage (11 cases), the contrast enhanced lesion around the hematoma showed marked BBB disruption according to the results of DCT. In 11 cases of cerebral infarction, patterns of BBB disruption and CBV varied at the contrast enhanced lesions according to the result of DCT. However, all contrast enhanced lesions with increased PH were associated with hemorrhagic infarction. Thus, the precise analysis of DCT provides appropriate therapeutic schedules by predicting the occurrence of hemorrhagic infarction. (author)

  14. Diagnosis of hepatic steatosis by contrast-enhanced abdominal computed tomography

    Directory of Open Access Journals (Sweden)

    Rodrigo da Fonseca Monjardim

    2013-06-01

    Full Text Available Objective To evaluate the diagnostic capacity of abdominal computed tomography in the assessment of hepatic steatosis using the portal phase with a simplified calculation method as compared with the non-contrast-enhanced phase. Materials and Methods In the present study, 150 patients were retrospectively evaluated by means of non-contrast-enhanced and contrast-enhanced computed tomography. One hundred patients had hepatic steatosis and 50 were control subjects. For the diagnosis of hepatic steatosis in the portal phase, the authors considered a result of < 104 HU calculated by the formula [L - 0.3 × (0.75 × P + 0.25 × A] / 0.7, where L, P and A represent the attenuation of the liver, of the main portal vein and abdominal aorta, respectively. Sensitivity, specificity, positive and negative predictive values were calculated, using non-contrast-enhanced computed tomography as the reference standard. Results The simplified calculation method with portal phase for the diagnosis of hepatic steatosis showed 100% sensitivity, 36% specificity, negative predictive value of 100% and positive predictive value of 75.8%. The rate of false positive results was 64%. False negative results were not observed. Conclusion The portal phase presents an excellent sensitivity in the diagnosis of hepatic steatosis, as compared with the non-contrast-enhanced phase of abdominal computed tomography. However, the method has low specificity.

  15. Contrast-enhanced magnetic resonance angiography of persistent fifth aortic arch in children

    International Nuclear Information System (INIS)

    Zhong, Yumin; Zhu, Ming; Sun, Aimin; Li, Yuhua; Jaffe, Richard B.; Gao, Wei

    2007-01-01

    Cine angiography and echocardiography have been utilized to diagnose congenital aortic arch anomalies. However, the visualization of great vessels by echocardiography is limited, while cine angiography requires cardiac catheterization with ionizing radiation. Contrast-enhanced magnetic resonance angiography (MRA) is a noninvasive modality suitable for visualization of congenital aortic arch anomalies. To evaluate the utility of contrast-enhanced MRA in the diagnosis of persistent fifth aortic arch, a rare congenital aortic arch anomaly, and to compare the diagnostic accuracy of MRA with that of echocardiography and cine angiography. In four pediatric patients, contrast-enhanced MRA studies were performed for diagnosing persistent fifth aortic arch. The findings of MRA were compared with echocardiographic findings and confirmed by cine angiography and operation. Transthoracic surface echocardiography noted an aberrant vessel arising from the ascending aorta in two of four patients; the etiology of this vessel was uncertain. In the other two patients a diagnosis of coarctation was made. Of the four patients, only one was diagnosed with interruption of the aortic arch. Contrast-enhanced MRA clarified uncertain echocardiographic findings, enabling the correct diagnosis of persistent fifth aortic arch with fourth aortic arch interruption in all four patients. Contrast-enhanced MRA is a safe, accurate, and fast imaging technique for the evaluation of persistent fifth aortic arch and may obviate the need for conventional cine angiography. Cardiac catheterization may be reserved for some types of complicated congenital heart disease and for obtaining hemodynamic information. (orig.)

  16. Contrast-enhanced power Doppler US of hepatocellular carcinomas: Quantitative analysis

    International Nuclear Information System (INIS)

    Kim, Ah Young; Choi, Byung Ihn; Kim, Tae Kyoung; Lee, Kyoung Ho; Han, Joon Koo

    1999-01-01

    To determine peak time and duration of contrast enhancement of nodular hepatocellular carcinoma (HCC) on contrast-enhancement power Doppler ultrasound (US) with Levovist by quantitative analysis. Twenty eight patients with nodular HCC were prospectively evaluated with power Doppler US by one examiner. Serial images were obtained before and after injection of 300 mg/mL US contrast agent (SH U 508 A, Levovist, Schering) with the injection rate of 0.2 mL/sec. Power Doppler signals on obtained digital images were quantified using 'Ultrasound Imaging Tool Version 1.0' (Seoul, Korea). The grade, peak time and duration of contrast enhancement of the tumors were analyzed. For nodular HCCs, mean peak enhancement time was 60 seconds after injection of Levovist (mean enhanced area 41.6 ± 28.6 %). These tumoral enhancement decreased from 90 seconds and returned to near baseline state at 5 minutes after injection of Levovist. Maximum enhanced areas (%) were variable at a range of 8-98.5% and mean maximum enhanced area was 46.4 ± 28.6%. On contrast-enhanced power Doppler US with Levovist, nodular HCCs showed peak contrast enhancement (41.6± 28.6) at 60 seconds after injection of contrast agent. This tumoral enhancement nearly disappeared at 5 minutes after injection of contrast agent.

  17. Value of fat suppression and dynamic contrast-enhanced MRI in the diagnosis of insulinoma

    International Nuclear Information System (INIS)

    Xu Zengbin; Ruan Lingxiang; Peng Zhiyi; Zhang Minming; Xu Shunliang; Zhang Xidao

    2003-01-01

    Objective: To evaluate the value of fat suppression and dynamic contrast-enhanced MRI in the preoperative localization of insulinoma. Methods: Twelve cases with pathologically proven insulinoma were evaluated with MRI. SE T 1 WI, FSE T 2 WI, T 1 WI and T 2 WI with fat suppression, dynamic contrast-enhanced FMPSPGR sequences were used in MR scanning. Results: On SE T 1 WI, the lesions displayed hypointense in 4, isointense in 8 cases. Lesions showed hyperintense in 4, isointense in 8 cases on FSE T 2 WI. In contrast, 7 cases appeared as hypointense on T 1 WI with fat suppression and 6 cases appeared as hyperintense on T 2 WI with fat suppression. With dynamic contrast-enhanced FMPSPGR sequence 11 of 12 insulinomas were detected. In the arterial phase, the lesions presented as hyperintense with different degrees in 11 cases and isointense in 1 case. 6 cases remained hyperintense and 6 cases were isointense in pancreatic parenchymal and portal phase. 4 lesions were identified only in dynamic enhancement images. The diagnostic accuracy of insulinoma by dynamic contrast-enhanced MRI was 91.7% (11/12) as compared with histological study. Conclusion: The results indicate that dynamic contrast-enhanced MRI is an sensitive and accurate method for the preoperative localization of insulinoma

  18. Contrast-enhanced ultrasonography of the liver using SonoVue

    Directory of Open Access Journals (Sweden)

    Giovanna Ferraioli

    2018-01-01

    Full Text Available This review focuses on the use of contrast-enhanced ultrasonography (CEUS with SonoVue (Bracco Imaging for the diagnosis of focal liver lesions (FLLs, guidance during ablative treatment, and follow-up of liver tumors. Multicenter trials have shown that the performance of CEUS for the characterization of FLLs is similar to that of contrast-enhanced computed tomography or contrast-enhanced magnetic resonance imaging. CEUS with SonoVue has been effectively used for guiding the percutaneous treatment of malignant liver tumors that are invisible or poorly visualized in traditional gray-scale ultrasonography. Postprocedural CEUS may be used to detect and retreat residual viable tissue in the same ablative session. The use of CEUS for the assessment of diffuse liver disease is also discussed.

  19. Contrast-enhanced ultrasonography of the liver using SonoVue.

    Science.gov (United States)

    Ferraioli, Giovanna; Meloni, Maria Franca

    2018-01-01

    This review focuses on the use of contrast-enhanced ultrasonography (CEUS) with SonoVue (Bracco Imaging) for the diagnosis of focal liver lesions (FLLs), guidance during ablative treatment, and follow-up of liver tumors. Multicenter trials have shown that the performance of CEUS for the characterization of FLLs is similar to that of contrast-enhanced computed tomography or contrast-enhanced magnetic resonance imaging. CEUS with SonoVue has been effectively used for guiding the percutaneous treatment of malignant liver tumors that are invisible or poorly visualized in traditional gray-scale ultrasonography. Postprocedural CEUS may be used to detect and retreat residual viable tissue in the same ablative session. The use of CEUS for the assessment of diffuse liver disease is also discussed.

  20. The role of contrast-enhanced ultrasound in risk assessment of carotid atheroma

    Directory of Open Access Journals (Sweden)

    Silviu Stanciu

    2016-07-01

    Full Text Available Background and objective: Contrast-enhanced ultrasound, used to assess atherosclerotic carotid plaques, improves visualization of vessel wall irregularities and depicts intraplaque neovascularization. This article illustrates the use of contrast-enhanced ultrasound in the risk assessment of carotid atherosclerotic lesions, especially in challenging plaques evaluation. Materials and methods: For 23 patients with difficult duplex ultrasound examination due to carotid tortuosity or calcifications we assessed plaque morphology (contour, echogenicity and stenosis degree using contrast substance (Sonovue, Braco with dedicated vascular low mechanical index CPC software. Conclusion: Contrast-enhanced ultrasound is a new, noninvasive, and safe procedure for imaging carotid atherosclerotic lesions. It is a valuable tool for evaluating the vulnerable plaque at risk for rupture and for the diagnostic of the development and severity of systemic atherosclerotic disease

  1. Contrast-enhanced helical CT of the breast cancer. CT and histopathological correlation

    Energy Technology Data Exchange (ETDEWEB)

    Furuhashi, Satoru [Yokosuka Municipal Hospital, Kanagawa (Japan); Karikomi, Masahito; Yano, Kiyoshi [and others

    2000-12-01

    This study was performed to evaluate the clinical utility of contrast-enhanced helical CT scan for the planning breast-conserving surgery. Fifty-four patients were evaluated by preoperative contrast-enhanced CT scan. The patients in a prone position were scanned with protocol of 2 mm section width and 2 mm/sec table speed. Scanning started with 70 sec. delay time at the tumor center after beginning the intravenous injection of 92 ml (27.6 mgI) of contrast material at the rate of 3 ml/sec. Tumor size displayed on CT scan was correlated well with the pathologic specimen (0.864, p<0.001). The sensitivity and specificity for the detection of ductal spread were 81.5% (22/27) and 73.1% (19/26), and accuracy was 75.9% (41/54). Contrast-enhanced helical CT has high reliability in planning breast-conserving surgery. (author)

  2. Delta-projection imaging on contrast-enhanced ultrasound to quantify tumor microvasculature and perfusion.

    Science.gov (United States)

    Sehgal, Chandra M; Cary, Theodore W; Arger, Peter H; Wood, Andrew K W

    2009-01-01

    The aim of this study was to assess the Delta-projection image processing technique for visualizing tumor microvessels and for quantifying the area of tissue perfused by them on contrast-enhanced ultrasound images. The Delta-projection algorithm was implemented to quantify perfusion by tracking the running maximum of the difference (Delta) between the contrast-enhanced ultrasound image sequence and a baseline image. Twenty-five mice with subcutaneous K1735 melanomas were first imaged with contrast-enhanced grayscale and then with minimum-exposure contrast-enhanced power Doppler (minexCPD) ultrasound. Delta-projection images were reconstructed from the grayscale images and then used to evaluate the evolution of tumor vascularity during the course of contrast enhancement. The extent of vascularity (ratio of the perfused area to the tumor area) for each tumor was determined quantitatively from Delta-projection images and compared to the extent of vascularity determined from contrast-enhanced power Doppler images. Delta-projection and minexCPD measurements were compared using linear regression analysis. Delta-projection was successfully performed in all 25 cases. The technique allowed the dynamic visualization of individual blood vessels as they filled in real time. Individual tumor blood vessels were distinctly visible during early image enhancement. Later, as an increasing number of blood vessels were filled with the contrast agent, clusters of vessels appeared as regions of perfusion, and the identification of individual vessels became difficult. Comparisons were made between the perfused area of tumors in Delta-projections and in minexCPD images. The Delta-projection perfusion measurements were correlated linearly with minexCPD. Delta-projection visualized tumor vessels and enabled the quantitative assessment of the tumor area perfused by the contrast agent.

  3. Differential diagnosis between pulmonary tuberculosis and lung abscess by contrast enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Kanauchi, Tetsu; Hoshi, Toshiko; Konno, Miyuki [Saitama Cardiovascular and Respiratory Center, Kohnan (Japan); Hando, Yumiko

    2001-01-01

    The contrast enhanced CT findings in 14 patients with active tuberculosis and 26 patients with lung abscess were retrospectively analyzed. Reflecting the difference of pathogenesis between tuberculosis and abscess, the findings are widely different. The findings suggesting pulmonary tuberculosis rather than lung abscess were as follows; multiple and irregular necrotic areas, positive CT angiogram sign, no marginal enhancement surrounding necrosis. Contrast enhanced CT may help to distinguish pulmonary tuberculosis from lung abscess, especially in cases of caseous pneumonia showing broad consolidations or mass-like shadows. (author)

  4. The complementary roles of dynamic contrast-enhanced MRI and {sup 18}F-fluorodeoxyglucose PET/CT for imaging of carotid atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Calcagno, Claudia; Ramachandran, Sarayu; Mani, Venkatesh; Millon, Antoine [Mount Sinai School of Medicine, Translational and Molecular Imaging Institute, One Gustave L. Levy Place, Box 1234, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States); Izquierdo-Garcia, David [Harvard University - MIT - Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA (United States); Rosenbaum, David [Hopital Pitie Salpetriere, Paris (France); Tawakol, Ahmed [Harvard Medical School and Massachusetts General Hospital, Boston, MA (United States); Woodward, Mark [University of Sydney, George Institute, Sydney (Australia); Bucerius, Jan [Maastricht University Medical Center, Department of Nuclear Medicine, Maastricht (Netherlands); Cardiovascular Research Institute Maastricht (CARIM), Maastricht (Netherlands); Rheinisch-Westfaelische Technische Hochschule Aachen, Department of Nuclear Medicine, Aachen (Germany); Moshier, Erin; Godbold, James [Mount Sinai School of Medicine, Biostatistics Shared Research Facility, New York, NY (United States); Kallend, David [F. Hoffmann-La Roche Ltd, Basel (Switzerland); Farkouh, Michael E. [Mount Sinai School of Medicine, Cardiovascular Institute, New York, NY (United States); Peter Munk Cardiac Centre and Li Ka Shing Knowledge Institute, Toronto (Canada); Fuster, Valentin [Mount Sinai School of Medicine, Cardiovascular Institute, New York, NY (United States); The Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid (Spain); Rudd, James H.F. [University of Cambridge, Division of Cardiovascular Medicine, Cambridge (United Kingdom); Fayad, Zahi A. [Mount Sinai School of Medicine, Translational and Molecular Imaging Institute, One Gustave L. Levy Place, Box 1234, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States); Mount Sinai School of Medicine, Cardiovascular Institute, New York, NY (United States)

    2013-12-15

    Inflammation and neovascularization in vulnerable atherosclerotic plaques are key features for severe clinical events. Dynamic contrast-enhanced (DCE) MRI and FDG PET are two noninvasive imaging techniques capable of quantifying plaque neovascularization and inflammatory infiltrate, respectively. However, their mutual role in defining plaque vulnerability and their possible overlap has not been thoroughly investigated. We studied the relationship between DCE-MRI and {sup 18}F-FDG PET data from the carotid arteries of 40 subjects with coronary heart disease (CHD) or CHD risk equivalent, as a substudy of the dal-PLAQUE trial (NCT00655473). The dal-PLAQUE trial was a multicenter study that evaluated dalcetrapib, a cholesteryl ester transfer protein modulator. Subjects underwent anatomical MRI, DCE-MRI and {sup 18}F-FDG PET. Only baseline imaging and biomarker data (before randomization) from dal-PLAQUE were used as part of this substudy. Our primary goal was to evaluate the relationship between DCE-MRI and {sup 18}F-FDG PET data. As secondary endpoints, we evaluated the relationship between (a) PET data and whole-vessel anatomical MRI data, and (b) DCE-MRI and matching anatomical MRI data. All correlations were estimated using a mixed linear model. We found a significant inverse relationship between several perfusion indices by DCE-MRI and {sup 18}F-FDG uptake by PET. Regarding our secondary endpoints, there was a significant relationship between plaque burden measured by anatomical MRI with several perfusion indices by DCE-MRI and {sup 18}F-FDG uptake by PET. No relationship was found between plaque composition by anatomical MRI and DCE-MRI or {sup 18}F-FDG PET metrics. In this study we observed a significant, weak inverse relationship between inflammation measured as {sup 18}F-FDG uptake by PET and plaque perfusion by DCE-MRI. Our findings suggest that there may be a complex relationship between plaque inflammation and microvascularization during the different

  5. Evaluation of Dixon Sequence on Hybrid PET/MR Compared with Contrast-Enhanced PET/CT for PET-Positive Lesions

    International Nuclear Information System (INIS)

    Jeong, Ju Hye; Cho, Ihn Ho; Kong, Eun Jung; Chun, Kyung Ah

    2014-01-01

    Hybrid positron emission tomography and magnetic resonance (PET/MR) imaging performs a two-point Dixon MR sequence for attenuation correction. However, MR data in hybrid PET/MR should provide anatomic and morphologic information as well as an attenuation map. We evaluated the Dixon sequence of hybrid PET/MR for anatomic correlation of PET-positive lesions compared with contrast-enhanced PET/computed tomography (CT) in patients with oncologic diseases. Twelve patients underwent a single injection, dual imaging protocol. PET/CT was performed with an intravenous contrast agent (85±13 min after 18 F-FDG injection of 403± 45 MBq) and then (125±19 min after injection) PET/MR was performed. Attenuation correction and anatomic allocation of PET were performed using contrast-enhanced CT for PET/CT and Dixon MR sequence for hybrid PET/MR. The Dixon MR sequence and contrast-enhanced CT were compared for anatomic correlation of PET-positive lesions (scoring scale ranging from 0 to 3 for visual ratings). Additionally, standardized uptake values (SUVs) for the detected lesions were assessed for quantitative comparison. Both hybrid PET/MR and contrast-enhanced PET/CT identified 55 lesions with increased FDG uptake in ten patients. In total, 28 lymph nodes, 11 bone lesions, 3 dermal nodules, 3 pleural thickening lesions, 2 thyroid nodules, 1 pancreas, 1 liver, 1 ovary, 1 uterus, 1 breast, 1 soft tissue and 2 lung lesions were present. The best performance was observed for anatomic correlation of PET findings by the contrast-enhanced CT scans (contrast-enhanced CT, 2.64± 0.70; in-phase, 1.29±1.01; opposed-phase, 1.29±1.15; water-weighted, 1.71±1.07; fat weighted, 0.56±1.03). A significant difference was observed between the scores obtained from the contrast-enhanced CT and all four coregistered Dixon MR images. Quantitative evaluation revealed a high correlation between the SUVs measured with hybrid PET/MR (SUVmean, 2.63±1.62; SUVmax, 4.30±2.88) and contrast-enhanced PET

  6. Evaluation of Dixon Sequence on Hybrid PET/MR Compared with Contrast-Enhanced PET/CT for PET-Positive Lesions

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ju Hye; Cho, Ihn Ho; Kong, Eun Jung; Chun, Kyung Ah [Yeungnam Univ. Hospital, Daegu (Korea, Republic of)

    2014-03-15

    Hybrid positron emission tomography and magnetic resonance (PET/MR) imaging performs a two-point Dixon MR sequence for attenuation correction. However, MR data in hybrid PET/MR should provide anatomic and morphologic information as well as an attenuation map. We evaluated the Dixon sequence of hybrid PET/MR for anatomic correlation of PET-positive lesions compared with contrast-enhanced PET/computed tomography (CT) in patients with oncologic diseases. Twelve patients underwent a single injection, dual imaging protocol. PET/CT was performed with an intravenous contrast agent (85±13 min after {sup 18}F-FDG injection of 403± 45 MBq) and then (125±19 min after injection) PET/MR was performed. Attenuation correction and anatomic allocation of PET were performed using contrast-enhanced CT for PET/CT and Dixon MR sequence for hybrid PET/MR. The Dixon MR sequence and contrast-enhanced CT were compared for anatomic correlation of PET-positive lesions (scoring scale ranging from 0 to 3 for visual ratings). Additionally, standardized uptake values (SUVs) for the detected lesions were assessed for quantitative comparison. Both hybrid PET/MR and contrast-enhanced PET/CT identified 55 lesions with increased FDG uptake in ten patients. In total, 28 lymph nodes, 11 bone lesions, 3 dermal nodules, 3 pleural thickening lesions, 2 thyroid nodules, 1 pancreas, 1 liver, 1 ovary, 1 uterus, 1 breast, 1 soft tissue and 2 lung lesions were present. The best performance was observed for anatomic correlation of PET findings by the contrast-enhanced CT scans (contrast-enhanced CT, 2.64± 0.70; in-phase, 1.29±1.01; opposed-phase, 1.29±1.15; water-weighted, 1.71±1.07; fat weighted, 0.56±1.03). A significant difference was observed between the scores obtained from the contrast-enhanced CT and all four coregistered Dixon MR images. Quantitative evaluation revealed a high correlation between the SUVs measured with hybrid PET/MR (SUVmean, 2.63±1.62; SUVmax, 4.30±2.88) and contrast-enhanced

  7. Feasibility and usefulness of using swallow contrast-enhanced ultrasound to diagnose Zenker's diverticulum: preliminary results.

    Science.gov (United States)

    Cui, Xin-Wu; Ignee, Andre; Baum, Ulrich; Dietrich, Christoph F

    2015-04-01

    Zenker's diverticulum (ZD) may be misdiagnosed on conventional ultrasound as a thyroid nodule or other lesion. A barium esophagram is usually used to confirm the diagnosis; however, this procedure exposes the patient to radiation. The aim of this study was to evaluate the feasibility of using swallow contrast-enhanced ultrasound (swallow-CEUS) to diagnose ZD. Ten consecutive patients with ZD (7 men and 3 women, aged 67 ± 11 y) were included in the study. In 4 patients, ZD was incidentally found on head and neck ultrasound, and in 6 patients, ZD was suspected because of dysphagia. All lesions could be detected on conventional ultrasound before swallow-CEUS. Ten healthy volunteers (8 men and 2 women, aged 60 ± 12 y) were chosen as a control group. Written informed consent was obtained. With the patient in the sitting or upright position, conventional ultrasound was performed first to image the lesion, then the patient was asked to swallow ultrasound contrast agent (UCA) (2-4 drops of SonoVue diluted with about 200 mL of tap water). Transity of the contrast agent in the esophagus was imaged with CEUS. Retention of the UCA in the diverticulum was monitored for at least 3 min. All patients underwent a barium esophagram as the gold standard. Swallow-CEUS revealed that in all patients (100%), the UCA was transported from the pharynx to the esophagus while the patient swallowed. ZD appeared as a pouch-shaped structure at the posterior pharyngo-esophageal junction that retained UCA longer than 3 min. The barium esophagram confirmed the diagnosis of ZD in all patients. For the 10 volunteers, no abnormal structure (retaining UCA) was detected during or after swallowing of UCA. With the advantages of no radiation and bedside availability, swallow-CEUS may become a method of choice in confirmation of the diagnosis of ZD, especially when ZD is suspected on conventional ultrasound. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier

  8. Correlative study of the parameters of dynamic contrast-enhanced MRI and angiogenesis in breast lesions

    International Nuclear Information System (INIS)

    Tang Guangyu; Xiao Xiangsheng; Liu Yong; Yao Yiping; Li Wei; Zhao Wenrong; Li Peng

    2007-01-01

    Objective: To evaluate the relationship between dynamic contrast-enhanced MRI (DCE-MRI)-derived parameters and tumor angiogenesis in malignant and benign breast lesions. Methods: Fifty-one patients with malignant and benign breast lesions underwent DCE-MRI using a Philips Intera 1.5 T MR System and dedicated breast coil prospectively before operation. DCE-MRI derived parameters such as steepest slope (S max )), peak height (PH), time-to-peak (T peak ) were calculated based on time-signal intensity curve. The micro-vessel density (MVD) was counted and vascular endothelial growth factor (VEGF) expression was assessed in these patients after operation with immunohistochemical staining method. The parameters were correlated statistically with MVD counts and VEGF expression in breast cancer. The MVD counts and VEGF expression were also compared among the patients with breast cancer (29 cases), with fibroadenoma (12 cases), mastopathy (10 cases) and the normal tissue (10 cases). Results: The enhancement parameters S max (r=0.807, P peak (69 ± 38) correlated negatively with MVD counts (r=-0.425, P< 0.05). The mean value of MVD (65.09±15.81/200 times field) in patients with breast cancer were significantly higher than those with fibroadenoma, mastopathy or normal tissue (P=0.043, 0.018, 0.002 respectively). 69% (20/29 cases) of breast cancers demonstrated positive VEGF expression, which were significantly more than that of fibroadenoma, mastopathy or normal tissue (P=0.035, 0.007, 0.001 respectively). Moreover, the MVD counts (60.38±24.14) in the peripheral region of breast cancer were more than those in central region (37.64±16.52; t=2.635, P=0.016). There was a significant difference in MVD counts between breast cancers with metastasis to axillary lymph nodes (73.23±23.02) and those without metastasis (59.34±18.03), (t=2.303, P=0.031). Conclusions: Some parameters derived from DCE-MRI correlated positively with MVD counts and VEGF expression in patients with breast

  9. Contrast-enhanced transrectal ultrasonography for the detection of diffuse prostate cancer.

    Science.gov (United States)

    Gao, Y; Liao, X H; Lu, L; Wang, L; Ma, Y; Qin, H Z; Yan, X; Guo, P

    2016-03-01

    To evaluate the diagnostic accuracy of contrast-enhanced transrectal ultrasonography (CE-TRUS) versus baseline TRUS (combination of grey-scale and colour Doppler imaging) for diffuse prostate cancer. Forty-six patients without an obvious focal mass on baseline TRUS (grey-scale and colour Doppler), underwent additional CE-TRUS and TRUS-guided biopsy due to elevated levels of prostate-specific antigen (PSA ≥4 ng/ml) and/or abnormal digital rectal examination (DRE). In all patients, CE-TRUS was performed with intravenous injection of a contrast agent (sulphur hexafluoride microbubble; SonoVue, 2.4 ml) before biopsy. TRUS-guided biopsy targeted suspicious areas detected on CE-TRUS imaging or sampled the outer gland of the normal prostate. The final diagnosis was based on results of the TRUS-guided biopsy. The diagnostic accuracy of baseline TRUS and CE-TRUS for diffuse prostatic lesions was evaluated using receiver operating characteristic (ROC) curve analysis. Diffuse prostate cancer was present in 32 (69.5%) patients and absent in 14 (30.5%) patients. Nineteen patients had diffuse prostate cancer that was not detected by baseline TRUS, whereas 15 cases were identified using CE-TRUS. Conversely, five patients had benign prostatic hypertrophy (BPH) that was diagnosed as cancer by CE-TRUS, and two of these patients were diagnosed with BPH by baseline TRUS. The combined sensitivity, specificity, and accuracy were 87.5%, 64.2%, and 80.4%, respectively, for CE-TRUS, and 40.6%, 78.5%, and 52.1%, respectively, for baseline TRUS. The area under the ROC curve (AUC) values for the diagnostic accuracy of baseline CE-TRUS versus TRUS for diffuse prostate cancer differed significantly at 0.904 and 0.667, respectively (Z=4.098, pprostate cancer than baseline TRUS. CE-TRUS may improve cancer detection over baseline TRUS imaging for the diagnosis of diffuse prostate cancer in patients with an elevated PSA level. CE-TRUS detects diffuse prostate cancer without an obvious focal mass

  10. Gender differences in contrast-enhanced magnetic resonance imaging after acute myocardial infarction.

    Science.gov (United States)

    Langhans, Birgit; Ibrahim, Tareq; Hausleiter, Jörg; Sonne, Carolin; Martinoff, Stefan; Schömig, Albert; Hadamitzky, Martin

    2013-03-01

    Besides different risk profiles for cardiovascular events in men and women, several studies reported gender differences in mortality after acute myocardial infarction (AMI). As infarct size has been shown to correlate with mortality, it is widely accepted as surrogate marker for clinical outcome. Currently, cardiovascular imaging studies covering the issue of gender differences are rare. As magnetic resonance scar characterization parameters are emerging as additional prognostic factors after acute myocardial infarction, we sought to evaluate gender differences in CMR infarct characteristics in patients after acute myocardial infarction. We prospectively analyzed patients (n = 448) with AMI and primary angioplasty, who underwent contrast-enhanced cardiac magnetic resonance (CMR) imaging on a 1.5 T scanner in median 5 [4, 6] days after the acute event. [corrected]. CMR scar size was measured 15 min after gadolinium injection. In addition presence and extent of microvascular obstruction (MVO) was assessed. A matched pair analysis was performed in order to exclude confounding by gender related co-morbidities and gender differences in established clinical risk factors. Matching process according to clinical risk defined by GRACE score resulted in 93 mixed gender couples. Women were significantly older than men (64.4 ± 11.9 vs. 60.5 ± 12.3, p = 0.03) and presented with a significantly better ejection fraction before angioplasty (48.9 ± 8.4 vs. 46.2 ± 8.9, p = 0.04). Infarct size did not differ significantly between women and men (13.5 ± 10.7 vs. 15.1 ± 11.8, p = 0.32). Size of MVO was significantly smaller in women than in men (0.48 ± 1.3 vs. 1.2 ± 3.0, p = 0.03). Comparing scar characterization between women and men with similar risk profiles revealed no gender differences in scar size. Size of MVO, however, was significantly smaller in women and might reflect better cardioprotective mechanisms in women. Whether these changes have prognostic implications has to

  11. Effects of arterial input function selection on kinetic parameters in brain dynamic contrast-enhanced MRI.

    Science.gov (United States)

    Keil, Vera C; Mädler, Burkhard; Gieseke, Jürgen; Fimmers, Rolf; Hattingen, Elke; Schild, Hans H; Hadizadeh, Dariusch R

    2017-07-01

    Kinetic parameters derived from dynamic contrast-enhanced MRI (DCE-MRI) were suggested as a possible instrument for multi-parametric lesion characterization, but have not found their way into clinical practice yet due to inconsistent results. The quantification is heavily influenced by the definition of an appropriate arterial input functions (AIF). Regarding brain tumor DCE-MRI, there are currently several co-existing methods to determine the AIF frequently including different brain vessels as sources. This study quantitatively and qualitatively analyzes the impact of AIF source selection on kinetic parameters derived from commonly selected AIF source vessels compared to a population-based AIF model. 74 patients with brain lesions underwent 3D DCE-MRI. Kinetic parameters [transfer constants of contrast agent efflux and reflux K trans and k ep and, their ratio, v e, that is used to measure extravascular-extracellular volume fraction and plasma volume fraction v p ] were determined using extended Tofts model in 821 ROI from 4 AIF sources [the internal carotid artery (ICA), the closest artery to the lesion, the superior sagittal sinus (SSS), the population-based Parker model]. The effect of AIF source alteration on kinetic parameters was evaluated by tissue type selective intra-class correlation (ICC) and capacity to differentiate gliomas by WHO grade [area under the curve analysis (AUC)]. Arterial AIF more often led to implausible v e >100% values (pkinetic parameters (pkinetic parameters of different AIF sources and tissues were variable (0.08-0.87) and only consistent >0.5 between arterial AIF derived kinetic parameters. Differentiation between WHO III and II glioma was exclusively possible with v p derived from an AIF in the SSS (p=0.03; AUC 0.74). The AIF source has a significant impact on absolute kinetic parameters in DCE-MRI, which limits the comparability of kinetic parameters derived from different AIF sources. The effect is also tissue-dependent. The SSS

  12. Supra-aortic low-dose contrast-enhanced time-resolved magnetic resonance (MR) angiography at 3 T: comparison with time-of-flight MR angiography and high-resolution contrast-enhanced MR angiography.

    Science.gov (United States)

    Lee, Youn-Joo; Kim, Bum-soo; Koo, Ja-Sung; Kim, Bom-Yi; Jang, Jinhee; Choi, Hyun Seok; Jung, So-Lyung; Ahn, Kook-Jin

    2015-06-01

    Low-dose, time-resolved, contrast-enhanced, magnetic resonance angiography (TR-CEMRA) has been described previously; however, a comparative study between low dose TR-CEMRA and time-of-flight MRA (TOF-MRA) in the diagnosis of supra-aortic arterial stenosis has not yet been published. To demonstrate the feasibility and effectiveness of low-dose TR-CEMRA compared with TOF-MRA, using high-resolution contrast-enhanced MRA (HR-CEMRA) as the reference standard. This prospective study consisted of 30 consecutive patients. All patients underwent TOF-MRA of the neck and circle of Willis and supra-aortic HR-CEMRA, followed by supra-aortic low-dose TR-CEMRA. Gadoterate meglumine (Gd-DOTA, Dotarem(®), Guerbet, Roissy CdG Cedex, France) was injected at a dose of 0.1 mmol/kg for HR-CEMRA, followed by a 0.03 mmol/kg bolus for low-dose TR-CEMRA. Three readers evaluated the assessibility and image quality, and then two readers classified each stenosis into the following categories: normal (0-30%), mild stenosis (31-50%), moderate (51-70%), severe (71-99%), and occlusion. TR-CEMRA and HR-CEMRA showed a greater number of assessable arterial segments than TOF-MRA (P supra-aortic arterial stenosis, and could be more useful option than TOF-MRA. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  13. Evaluation of liver parenchyma and perfusion using dynamic contrast-enhanced computed tomography and contrast-enhanced ultrasonography in captive green iguanas (Iguana iguana) under general anesthesia.

    Science.gov (United States)

    Nardini, Giordano; Di Girolamo, Nicola; Leopardi, Stefania; Paganelli, Irene; Zaghini, Anna; Origgi, Francesco C; Vignoli, Massimo

    2014-05-13

    Contrast-enhanced diagnostic imaging techniques are considered useful in veterinary and human medicine to evaluate liver perfusion and focal hepatic lesions. Although hepatic diseases are a common occurrence in reptile medicine, there is no reference to the use of contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT) to evaluate the liver in lizards. Therefore, the aim of this study was to evaluate the pattern of change in echogenicity and attenuation of the liver in green iguanas (Iguana iguana) after administration of specific contrast media. An increase in liver echogenicity and density was evident during CEUS and CECT, respectively. In CEUS, the mean ± SD (median; range) peak enhancement was 19.9% ± 7.5 (18.3; 11.7-34.6). Time to peak enhancement was 134.0 ± 125.1 (68.4; 59.6-364.5) seconds. During CECT, first visualization of the contrast medium was at 3.6 ± 0.5 (4; 3-4) seconds in the aorta, 10.7 ± 2.2 (10.5; 7-14) seconds in the hepatic arteries, and 15 ± 4.5 (14.5; 10-24) seconds in the liver parenchyma. Time to peak was 14.1 ± 3.4 (13; 11-21) and 31 ± 9.6 (29; 23-45) seconds in the aorta and the liver parenchyma, respectively. CEUS and dynamic CECT are practical means to determine liver hemodynamics in green iguanas. Distribution of contrast medium in iguana differed from mammals. Specific reference ranges of hepatic perfusion for diagnostic evaluation of the liver in iguanas are necessary since the use of mammalian references may lead the clinician to formulate incorrect diagnostic suspicions.

  14. Characterization of the enhancing lesions on dynamic contrast enhanced magnetic resonance imaging in patients with interstitial mammoplasty

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    Kim, Tae Yun [Department of Radiology, Seoul St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Kim, Sung Hun, E-mail: rad-ksh@catholic.ac.kr [Department of Radiology, Seoul St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Kang, Bong Joo [Department of Radiology, Seoul St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Kim, Hyeon Sook [Department of Radiology, St. Paul Hospital, The Catholic University of Korea (Korea, Republic of); Cha, Eun Suk [Department of Radiology, Ewha Womans University, School of Medicine, Mokdong Hospital (Korea, Republic of); Kim, Ji Youn [Department of Radiology, Yeouido St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Song, Byung Joo [Department of Surgery, Seoul St. Mary' s Hospital, The Catholic University of Korea, Seoul (Korea, Republic of)

    2013-12-01

    Purpose: The purpose of this study was to categorize the morphologic and kinetic features of enhancing lesions in breasts with interstitial mammoplasty using dynamic contrast-enhanced magnetic resonance imaging and to assess factors predictive of breast cancer. Materials and methods: We retrospectively reviewed the clinical and radiological data of 21 enhancing lesions in 19 patients with interstitial mammoplasty, who underwent breast magnetic resonance imaging and biopsy or an operation in our hospital from September 2008 to July 2012. These lesions were sorted by morphological and kinetic features and final assessment category according to the BI-RADS lexicon. Results: Nine cases were confirmed to be ductal carcinoma in situ (n = 2) and invasive ductal carcinoma (n = 7), and the remaining 12 cases were fibrocystic disease (n = 2), fibroadenoma (n = 2), fat necrosis (n = 1), foreign body granuloma (n = 3) and silicone mastitis (n = 1). Common features of malignancy included irregular shape (50.0%), spiculated margins (75.0%), heterogeneous enhancement (50.0%) and type III kinetic pattern (87.5%). The correlations of margins and kinetic curve pattern with benignity and malignancy approached statistical significance (p = 0.02, respectively). We found no correlation for shape (p = 0.33) or internal enhancement (p = 0.42) between lesion types. The malignancy rate of enhancing lesions was 42.8% (9/21). The sensitivity and specificity of dynamic contrast-enhanced magnetic resonance imaging were 100% and 16.67%, respectively. The positive predictive value, negative predictive value and accuracy of magnetic resonance imaging were 47.38%, 100% and 52.38%. Overall inter-observer agreement for the kinetic curve pattern was good (κ = 0.67). Moderate agreement was seen in describing the shape, margin, enhancement and assessing the final category (κ = 0.59, 0.46, 0.58 and 0.49, respectively). Conclusion: Dynamic contrast-enhanced magnetic resonance imaging had a high

  15. Dynamic contrast-enhanced MRI assessment of hyperemic fractional microvascular blood plasma volume in peripheral arterial disease: initial findings.

    Directory of Open Access Journals (Sweden)

    Bas Versluis

    Full Text Available OBJECTIVES: The aim of the current study was to describe a method that assesses the hyperemic microvascular blood plasma volume of the calf musculature. The reversibly albumin binding contrast agent gadofosveset was used in dynamic contrast-enhanced magnetic resonance imaging (DCE MRI to assess the microvascular status in patients with peripheral arterial disease (PAD and healthy controls. In addition, the reproducibility of this method in healthy controls was determined. MATERIALS AND METHODS: Ten PAD patients with intermittent claudication and 10 healthy control subjects were included. Patients underwent contrast-enhanced MR angiography of the peripheral arteries, followed by one DCE MRI examination of the musculature of the calf. Healthy control subjects were examined twice on different days to determine normative values and the interreader and interscan reproducibility of the technique. The MRI protocol comprised dynamic imaging of contrast agent wash-in under reactive hyperemia conditions of the calf musculature. Using pharmacokinetic modeling the hyperemic fractional microvascular blood plasma volume (V(p, unit: % of the anterior tibial, gastrocnemius and soleus muscles was calculated. RESULTS: V(p was significantly lower for all muscle groups in PAD patients (4.3±1.6%, 5.0±3.3% and 6.1±3.6% for anterior tibial, gastrocnemius and soleus muscles, respectively compared to healthy control subjects (9.1±2.0%, 8.9±1.9% and 9.3±2.1%. Differences in V(p between muscle groups were not significant. The coefficient of variation of V(p varied from 10-14% and 11-16% at interscan and interreader level, respectively. CONCLUSIONS: Using DCE MRI after contrast-enhanced MR angiography with gadofosveset enables reproducible assessment of hyperemic fractional microvascular blood plasma volume of the calf musculature. V(p was lower in PAD patients than in healthy controls, which reflects a promising functional (hemodynamic biomarker for the

  16. Non-contrast enhanced MRI for evaluation of breast lesions: comparison of non-contrast enhanced high spectral and spatial resolution (HiSS) images vs. contrast enhanced fat-suppressed images

    Science.gov (United States)

    Medved, Milica; Fan, Xiaobing; Abe, Hiroyuki; Newstead, Gillian M.; Wood, Abbie M.; Shimauchi, Akiko; Kulkarni, Kirti; Ivancevic, Marko K.; Pesce, Lorenzo L.; Olopade, Olufunmilayo I.; Karczmar, Gregory S.

    2011-01-01

    RATIONALE AND OBJECTIVES To evaluate high spectral and spatial resolution (HiSS) MRI for diagnosis of breast cancer without injection of contrast media: to compare the performance of pre-contrast HiSS images to conventional contrast-enhanced fat-suppressed T1-weighted images, based on image quality and in the task of classifying benign and malignant breast lesions. MATERIALS AND METHODS Ten benign and 44 malignant lesions were imaged at 1.5T with HiSS (pre-contrast administration) and conventional fat-suppressed imaging (3–10 min post-contrast). This set of 108 images, after randomization, was evaluated by three experienced radiologists blinded to the imaging technique. BIRADS morphologic criteria (lesion shape; lesion margin; internal signal intensity pattern) and final assessment were used to measure reader performance. Image quality was evaluated based on boundary delineation and quality of fat suppression. An overall probability of malignancy was assigned to each lesion for HiSS and conventional images separately. RESULTS On boundary delineation and quality of fat-suppression, pre-contrast HiSS scored similarly to conventional post-contrast MRI. On benign vs. malignant lesion separation, there was no statistically significant difference in ROC performance between HiSS and conventional MRI, and HiSS met a reasonable non-inferiority condition. CONCLUSION Pre-contrast HiSS imaging is a promising approach for showing lesion morphology without blooming and other artifacts caused by contrast agents. HiSS images could be used to guide subsequent dynamic contrast-enhanced MRI scans, to maximize spatial and temporal resolution in suspicious regions. HiSS MRI without contrast agent injection may be particularly important for patients at risk for contrast-induced nephrogenic systemic fibrosis, or allergic reactions. PMID:21962476

  17. Accuracy of contrast-enhanced dual-energy MDCT for the assessment of iodine uptake in renal lesions.

    Science.gov (United States)

    Mileto, Achille; Marin, Daniele; Ramirez-Giraldo, Juan Carlos; Scribano, Emanuele; Krauss, Bernhard; Mazziotti, Silvio; Ascenti, Giorgio

    2014-05-01

    The objective of our study was to assess the accuracy of iodine-related attenuation and iodine quantification as imaging biomarkers of iodine uptake in renal lesions on a single-phase nephrographic image with dual-energy MDCT. Fifty-nine patients (41 men, 18 women; age range, 28-84 years) with 80 renal lesions underwent contrast-enhanced dual-energy CT during the nephrographic phase of enhancement. Renal lesions were characterized as enhancing or nonenhancing on color-coded iodine overlay maps using iodine-related attenuation (in Hounsfield units) and iodine quantification (in milligrams per milliliter). For iodine-related attenuation the iodine uptake thresholds of 15 and 20 HU were tested; a threshold of 0.5 mg/mL was used for iodine quantification. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of iodine-related attenuation and iodine quantification were calculated from chi-square tests of contingency with histopathology or imaging follow-up as the reference standard. The 95% CIs were calculated from binomial expression. Differences in sensitivity and specificity were assessed by means of McNemar analysis. A significant difference in sensitivity and specificity was found between iodine-related attenuation with the thresholds of 15 HU (sensitivity, 91.4%; specificity, 93.3%; PPV, 91.4%; NPV, 93.3%) and 20 HU (sensitivity, 77.1%; specificity, 100%; PPV, 100%; NPV, 84.9%) (p = 0.008) and between iodine quantification (sensitivity, 100%; specificity, 97.7%; PPV, 97.2%; NPV, 100%) and iodine-related attenuation with a threshold of 20 HU (p = 0.004). No significant difference in sensitivity and specificity was found between iodine quantification and iodine-related attenuation with a threshold of 15 HU. Contrast-enhanced dual-energy MDCT with iodine-related attenuation and iodine quantification allows accurate evaluation of iodine uptake in renal lesions on a single-phase nephrographic image.

  18. Preliminary clinical application of contrast-enhanced MR angiography using three-dimensional time-resolved imaging of contrast kinetics

    International Nuclear Information System (INIS)

    Yang Chunshan; Zhang Song; Zhou Kangrong; Liu Shiyuan Xiao Xiangsheng; Wang Jinlin; Li Huimin; Xiao Shan; Gong Wanqing

    2007-01-01

    Objective: To assess the clinical application of contrast-enhanced MR angiography using three-dimensional (3D) time-resolved imaging of contrast kinetics (CE-MRA 3D-TRICKS). Methods: TRICKS is a high temporal resolution (2-6 s) MR angiographic technique using a short TR (2.8- 4.0 ms) and TE (0.9-1.3 ms), partial echo sampling and the central part of the k-space being updated more frequently than the peripheral part of the k-space. Pre-contrast mask 3D images are first acquired and 15-20 sequential 3D images following bolus injection of Gd-DTPA are then acquired. Results: Thirty patients underwent contrast-enhanced MR angiography using TRICKS. Twelve vertebral arteries were well displayed on TRICKS. Seven of them showed normal, bilateral vertebral artery stenosis was shown in 1 case, and unilateral vertebral artery stenosis was shown in 4 wth accompaning ipsilateral carotid artery bifurcation stenosis in one case. Bilateral renal artery showed normal in 4 cases, and the artery in transplanted kidney showed normal in one case and stenosis in another case. The cerebral artery showed normal in 2 cases, sagittal sinus thrombosis was detected in one case and intracranial arteriovenous malformation in one case. Pulmonary artery displayed normal in 3 cases, pulmonary artery thrombosis was seen in one case and pulmonary sequestration's abnormal feeding artery and draining vein was revealed in one case. The feeding artery in left lower limb fibrolipoma was showed in one case. The radial-ulnar artery artificial fistula stenosis was seen in one case, and left antebrachium hemangioma was showed in one case. Conclusion: TRICKS can clearly delineate the whole body vascular system and can reveal any vascular abnormality. It is convenient and with high successful rate, which make it the first method of choice in displaying vascular abnormality. (authors)

  19. Diagnostic accuracy of magnetic resonance, computed tomography and contrast enhanced ultrasound in radiological multimodality assessment of peribiliary liver metastases.

    Directory of Open Access Journals (Sweden)

    Vincenza Granata

    Full Text Available We compared diagnostic performance of Magnetic Resonance (MR, Computed Tomography (CT and Ultrasound (US with (CEUS and without contrast medium to identify peribiliary metastasis.We identified 35 subjects with histological proven peribiliary metastases who underwent CEUS, CT and MR study. Four radiologists evaluated the presence of peribiliary lesions, using a 4-point confidence scale. Echogenicity, density and T1-Weigthed (T1-W, T2-W and Diffusion Weighted Imaging (DWI signal intensity as well as the enhancement pattern during contrast studies on CEUS, CT and MR so as hepatobiliary-phase on MRI was assessed.All lesions were detected by MR. CT detected 8 lesions, while US/CEUS detected one lesion. According to the site of the lesion, respect to the bile duct and hepatic parenchyma: 19 (54.3% were periductal, 15 (42.8% were intra-periductal and 1 (2.8% was periductal-intrahepatic. According to the confidence scale MRI had the best diagnostic performance to assess the lesion. CT obtained lower diagnostic performance. There was no significant difference in MR signal intensity and contrast enhancement among all metastases (p>0.05. There was no significant difference in CT density and contrast enhancement among all metastases (p>0.05.MRI is the method of choice for biliary tract tumors but it does not allow a correct differential diagnosis among different histological types of metastasis. The presence of biliary tree dilatation without hepatic lesions on CT and US/CEUS study may be an indirect sign of peribiliary metastases and for this reason the patient should be evaluated by MRI.

  20. Contrast-enhanced duplex scanning of crural arteries by means of continuous infusion of Levovist

    NARCIS (Netherlands)

    Coffi, Stephen B.; Ubbink, Dirk Th; Zwiers, Ineke; van Gurp, Johan A. M.; Hanson, Dianne; Legemate, Dink A.

    2004-01-01

    Objectives: To estimate the dosage needed for continuous infusion and to investigate whether continuous infusion of the ultrasound contrast-enhancing agent Levovist (SH U 508A) can improve duplex scanning of crural arteries in patients with peripheral arterial obstructive disease (PAOD) eligible for

  1. Dynamics of contrast enhancement in MR imaging and power Doppler ultrasonography of solid breast lesions

    International Nuclear Information System (INIS)

    Reinikainen, H.; Paeaekkoe, E.; Suramo, I.; Paeivaensalo, M.; Rissanen, T.

    2002-01-01

    Purpose: To evaluate the dynamics of contrast enhancement in solid breast lesions at contrast-enhanced MR imaging and power Doppler ultrasonography (US) and to compare the methods to histology and to each other. Material and Methods: Forty breast lesions were prospectively examined with dynamic MR and power Doppler US. Time-signal intensity curves of enhancement were obtained for both methods. The shape of the curve was analyzed to be benign, indeterminate or malignant. The curves were also analyzed quantitatively by calculating the slope of the curve and the area under the curve (both methods), relative enhancement (MR), and time to peak (US). The lesions were divided into malignant lesions, fibroadenomas, and other benign lesions. The results were compared to histology. Results: In the subjective analysis of the MR curve in differentiating between benign and malignant lesions the accuracy was 90%. The MR curve also enabled differentiation between fibroadenomas and malignancies. The accuracy of the US curve was 38%. Quantitatively, statistically significant differences were found using all the MR variables, except between malignancies and fibroadenomas. Using the US variables, no significant difference was found between the groups. Conclusion: The dynamics of contrast-enhanced MR were reliable in the differential diagnosis of solid breast lesions, but contrast-enhanced power Doppler US was of limited value

  2. Contrast-enhanced dental MRI for visualization of the teeth and jaw.

    Science.gov (United States)

    Olt, Silvia; Jakob, Peter M

    2004-07-01

    A technique for contrast-enhanced dental MRI is described that enables 3D visualization of the oral cavity, including the jaw and teeth. Since teeth are MR-invisible, the basic principle of this technique is that the teeth and jaw can be observed indirectly through contrast with a surrounding MR-visible medium. For this purpose, the oral cavity is filled with a nontoxic substance, such as water or MR contrast media, that gives a high MR signal. A 3D data set covering the entire buccal space is acquired, and the image intensities are inverted. Since isosurface reconstructions of the teeth and jaw, as well as panoramic views analogous to orthopantomography, can be extracted from these data, contrast-enhanced dental MRI may be useful as a flexible tool for dentistry and orthodontics. Moreover, contrast-enhanced dental MRI works without radiation exposure, and therefore it is an interesting alternative to X-ray-based imaging modalities such as conventional radiography and dental CT. In this article, some preliminary results obtained with contrast-enhanced dental MRI are shown in order to demonstrate the feasibility and performance of this new approach. Copyright 2004 Wiley-Liss, Inc.

  3. Image contrast enhancement using adjacent-blocks-based modification for local histogram equalization

    Science.gov (United States)

    Wang, Yang; Pan, Zhibin

    2017-11-01

    Infrared images usually have some non-ideal characteristics such as weak target-to-background contrast and strong noise. Because of these characteristics, it is necessary to apply the contrast enhancement algorithm to improve the visual quality of infrared images. Histogram equalization (HE) algorithm is a widely used contrast enhancement algorithm due to its effectiveness and simple implementation. But a drawback of HE algorithm is that the local contrast of an image cannot be equally enhanced. Local histogram equalization algorithms are proved to be the effective techniques for local image contrast enhancement. However, over-enhancement of noise and artifacts can be easily found in the local histogram equalization enhanced images. In this paper, a new contrast enhancement technique based on local histogram equalization algorithm is proposed to overcome the drawbacks mentioned above. The input images are segmented into three kinds of overlapped sub-blocks using the gradients of them. To overcome the over-enhancement effect, the histograms of these sub-blocks are then modified by adjacent sub-blocks. We pay more attention to improve the contrast of detail information while the brightness of the flat region in these sub-blocks is well preserved. It will be shown that the proposed algorithm outperforms other related algorithms by enhancing the local contrast without introducing over-enhancement effects and additional noise.

  4. Spleen evaluation using contrast enhanced ultrasonography and Doppler in dogs with subclinical ehrlichiosis

    Directory of Open Access Journals (Sweden)

    M.C. Maronezi

    2015-12-01

    Full Text Available The aim of this study was to evaluate the splenic parenchyma of dogs with subclinical ehrlichiosis using Doppler and contrast-enhanced ultrasonography and provide reference values for this organ in affected animals. Seventeen dogs naturally infected with E. canis were selected for this study. Splenic parenchyma echotexture and echogenicity, size and borders were determined by ultrasound scan. The vascular indices of the splenic artery were determined by Doppler. SonoVue, at 0.1mL per animal, was used in microbubble contrast-enhanced ultrasonography to determine wash in, wash out and peak enhancement time in the splenic tissue. B-mode ultrasonography revealed splenomegaly with rounded borders, heterogeneous echotexture and mixed echogenicity. The vascular indices of the splenic artery were: systolic velocity of 22.59±8.07cm/s, diastolic velocity of 5.25±4.66cm/s and resistance index of 0.71±0.14; values not yet reported in Veterinary Medicine. Contrast-enhanced ultrasonography recorded wash in time of 5.31±0.7s, peak enhancement time of 18.56±2.90s and wash out time of 94.56±35.21s. The combination of conventional ultrasonography of the spleen and hemodynamic evaluation by Doppler and contrast-enhanced ultrasonography is important for the diagnosis of canine ehrlichiosis and could help monitor the clinical evolution of subclinical cases.

  5. Medical Image Visual Appearance Improvement Using Bihistogram Bezier Curve Contrast Enhancement: Data from the Osteoarthritis Initiative

    Science.gov (United States)

    Gan, Hong-Seng; Swee, Tan Tian; Abdul Karim, Ahmad Helmy; Sayuti, Khairil Amir; Abdul Kadir, Mohammed Rafiq; Tham, Weng-Kit; Wong, Liang-Xuan; Chaudhary, Kashif T.; Yupapin, Preecha P.

    2014-01-01

    Well-defined image can assist user to identify region of interest during segmentation. However, complex medical image is usually characterized by poor tissue contrast and low background luminance. The contrast improvement can lift image visual quality, but the fundamental contrast enhancement methods often overlook the sudden jump problem. In this work, the proposed bihistogram Bezier curve contrast enhancement introduces the concept of “adequate contrast enhancement” to overcome sudden jump problem in knee magnetic resonance image. Since every image produces its own intensity distribution, the adequate contrast enhancement checks on the image's maximum intensity distortion and uses intensity discrepancy reduction to generate Bezier transform curve. The proposed method improves tissue contrast and preserves pertinent knee features without compromising natural image appearance. Besides, statistical results from Fisher's Least Significant Difference test and the Duncan test have consistently indicated that the proposed method outperforms fundamental contrast enhancement methods to exalt image visual quality. As the study is limited to relatively small image database, future works will include a larger dataset with osteoarthritic images to assess the clinical effectiveness of the proposed method to facilitate the image inspection. PMID:24977191

  6. Contrast enhanced ultrasound for the diagnosis of liver hemangiomas - results of a Romanian multicentre study

    DEFF Research Database (Denmark)

    Sirli, Roxana; Sporea, Ioan; Săndulescu, Daniela Larisa

    2015-01-01

    BACKGROUND AND AIM: Contrast enhanced ultrasound (CEUS) has been proven to be a reliable method for the characterization of focal liver lesions (FLL). The aim of this paper was to evaluate the performance of CEUS for the diagnosis of liver hemangiomas in a large cohort of patients. MATERIAL...

  7. Contrast-enhanced dynamic MR imaging of postmolar gestational trophoblastic disease

    International Nuclear Information System (INIS)

    Yamashita, Y.; Torashima, M.; Takahashi, M.; Mizutani, H.; Miyazaki, K.; Matsuura, K.; Okamura, H.

    1995-01-01

    Conventional spin-echo (SE) and contrast-enhanced dynamic MR imaging were performed on a 1.5 T superconductive unit for evaluation of myometrial lesions in postmolar gestational trophoblastic disease (GTD) in 10 women. MR imaging was done at the time of the initial examination (n=10), during (n=6), and after repeated courses of chemotherapy (n=10). The T2-weighted SE image revealed an enlarged uterus (n=7), disappearance of zonal anatomy (n=6), and heterogeneous signal intensities (n=8) with prominent flow voids (n=7). However, these abnormalities remained after repeated courses of chemotherapy, when the S-β-HCG level returned to the normal range. Myometrial lesions characteristically had marked enhancement with areas of unenhancement on dynamic MR images in patients with highly elevated S-β-HCG. Areas of contrast enhancement correlated with changes in S-β-HCG level. The enhancement was reduced with decrease in S-β-HCG level after repeated courses of chemotherapy. Six of 8 masses seen on T2-weighted images proved to be active trophoblastic lesions and 2 masses proved to be hematoma or necrosis. In 2 patients, abnormal myometrial lesions were detected only on contrast-enhanced dynamic MR imaging. These preliminary data indicate that contrast-enhanced dynamic MR imaging more clearly demonstrates myometrial involvement of postmolar GTD than conventional SE imaging. (orig.)

  8. Dynamic contrast-enhanced MRI in patients with luminal Crohn's disease

    NARCIS (Netherlands)

    Ziech, M. L. W.; Lavini, C.; Caan, M. W. A.; Nio, C. Y.; Stokkers, P. C. F.; Bipat, S.; Ponsioen, C. Y.; Nederveen, A. J.; Stoker, J.

    2012-01-01

    Objectives: To prospectively assess dynamic contrast-enhanced (DCE-)MRI as compared to conventional sequences in patients with luminal Crohn's disease. Methods: Patients with Crohn's disease undergoing MRI and ileocolonoscopy within 1 month had DCE-MRI (3T) during intravenous contrast injection of

  9. Avascular necrosis of femoral head: findings of contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Shin, Yong Moon; Kang, Heung Sik; Kim, Chu Wan; Kim, Hee Joong; Kim, Young Min

    1995-01-01

    To evaluate the findings and the role of contrast enhanced magnetic resonance imaging in avascular necrosis of femoral head. Sixteen patients with avascular necorsis of femoral head were examined with MRI. T1-weighted and T2-weighted image and contrast-enhanced T1-weighted images were obtained. Enhancing characteristics of the necrotic area and synovium were determined. Also a change of the disease extent after enhancement was assessed. Twenty seven avascular necrosis of the femoral head including 11 cases of bilateral lesion were detected. Fifteen cases revealed collapse of the femoral head. The portions of the lesion with low signal intensity on T1-weighted images and high signal intensity on T2-weighted images showed contrast enhancement in 15 cases. However, the potions with low signal intensities both on T1 and T2-weighted images showed enhancement in one case. There was no significant change of the disease extent after enhancement. Synovium showed enhancement in 18 cases, and joint effusion was detected in 23 cases. Contrast enhanced MR images may be helpful in predicting histopathologic findings of avascular necrosis of the femoral head, but not useful for evaluating the extent of disease

  10. Hepatic blood perfusion estimated by dynamic contrast-enhanced computed tomography in pigs

    DEFF Research Database (Denmark)

    Winterdahl, Michael; Sørensen, Michael; Keiding, Inger Susanne

    2012-01-01

    The aim of this study was to determine whether dynamic contrast-enhanced computed tomography (DCE-CT) and the slope method can provide absolute measures of hepatic blood perfusion from the hepatic artery (HA) and portal vein (PV) at experimentally varied blood flow rates....

  11. An Algorithmic Analysis of Variational Models for Perceptual Local Contrast Enhancement

    Directory of Open Access Journals (Sweden)

    Sira Ferradans

    2015-07-01

    Full Text Available Color cast cancellation and local contrast enhancement are very important problems in computervision. In this paper we review the algorithm proposed by Palma-Amestoy et al. [A perceptuallyinspired variational framework for color enhancement, IEEE Transactions on Pattern Analysisand Machine Intelligence, 21 (2009, pp. 458–474], present results and evaluate the impact of achange in the parameters.

  12. Contrast enhanced digital mammography: Is it useful in detecting lesions in edematous breast?

    Directory of Open Access Journals (Sweden)

    Noha Abd ElShafy ElSaid

    2015-09-01

    Conclusion: Dual-energy contrast-enhanced digital mammography is a useful technique in identification of lesions in mammographically dense edematous breasts and proved to be a useful tool in the follow-up of cases presenting by edema after conservative breast surgery and chemotherapy.

  13. Assessment of Prostate Cancer Aggressiveness Using Dynamic Contrast-enhanced Magnetic Resonance Imaging at 3 T

    NARCIS (Netherlands)

    Vos, E.K.; Litjens, G.J.S.; Kobus, T.; Hambrock, T.; Kaa, C.A. van de; Barentsz, J.O.; Huisman, H.J.; Scheenen, T.W.J.

    2013-01-01

    BACKGROUND: A challenge in the diagnosis of prostate cancer (PCa) is the accurate assessment of aggressiveness. OBJECTIVE: To validate the performance of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) of the prostate at 3 tesla (T) for the assessment of PCa aggressiveness, with

  14. Feasibility of contrast-enhanced cone-beam CT for target localization and treatment monitoring

    International Nuclear Information System (INIS)

    Rodal, Jan; Sovik, Aste; Skogmo, Hege Kippenes; Knudtsen, Ingerid Skjei; Malinen, Eirik

    2010-01-01

    A dog with a spontaneous maxillary tumour was given 40 Gy of fractionated radiotherapy. At five out of 10 fractions cone-beam CT (CBCT) imaging before and after administration of an iodinated contrast agent were performed. Contrast enhancement maps were overlaid on the pre-contrast CBCT images. The tumour was clearly visualized in the images thus produced.

  15. Modeling Dynamic Contrast-Enhanced MRI Data with a Constrained Local AIF

    DEFF Research Database (Denmark)

    Duan, Chong; Kallehauge, Jesper F.; Pérez-Torres, Carlos J

    2018-01-01

    PURPOSE: This study aims to develop a constrained local arterial input function (cL-AIF) to improve quantitative analysis of dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI) data by accounting for the contrast-agent bolus amplitude error in the voxel-specific AIF. PROCEDURES...

  16. Contrast enhancement by lipid-based MRI contrast agents in mouse atherosclerotic plaques; a longitudinal study

    NARCIS (Netherlands)

    den Adel, Brigit; van der Graaf, Linda M.; Que, Ivo; Strijkers, Gustav J.; Löwik, Clemens W.; Poelmann, Robert E.; van der Weerd, Louise

    2013-01-01

    The use of contrast-enhanced MRI to enable in vivo specific characterization of atherosclerotic plaques is increasing. In this study the intrinsic ability of two differently sized gadolinium-based contrast agents to enhance atherosclerotic plaques in ApoE(-/-) mice was evaluated with MRI. We

  17. Dynamic contrast-enhanced (DCE) imaging for tumor delineation in prostate cancer

    NARCIS (Netherlands)

    Korporaal, J.G.

    2011-01-01

    Dynamic contrast-enhanced (DCE) MR imaging is frequently used for the detection and localization of prostate tumors. After injection of a bolus of contrast agent into the blood circulation, the behavior of the contrast agent in the prostate can be measured by repetitive imaging of the prostate.

  18. Evaluating automated dynamic contrast enhanced wrist 3T MRI in healthy volunteers

    DEFF Research Database (Denmark)

    Rastogi, Anshul; Kubassova, Olga; Krasnosselskaia, Lada V

    2013-01-01

    Dynamic contrast enhanced (DCE)-MRI has great potential to provide quantitative measure of inflammatory activity in rheumatoid arthritis. There is no current benchmark to establish the stability of signal in the joints of healthy subjects when imaged with DCE-MRI longitudinally, which is crucial ...

  19. Counter-propagating wave interaction for contrast-enhanced ultrasound imaging

    NARCIS (Netherlands)

    G. Renaud (G.); J.G. Bosch (Hans); E.J.G. Sijbrands (Eric); V. Shamdasani (V.); R. Entrekin (R.); N. de Jong (Nico); A.F.W. van der Steen (Ton)

    2012-01-01

    textabstractMost techniques for contrast-enhanced ultrasound imaging require linear propagation to detect nonlinear scattering of contrast agent microbubbles. Waveform distortion due to nonlinear propagation impairs their ability to distinguish microbubbles from tissue. As a result, tissue can be

  20. Medical Image Visual Appearance Improvement Using Bihistogram Bezier Curve Contrast Enhancement: Data from the Osteoarthritis Initiative

    Directory of Open Access Journals (Sweden)

    Hong-Seng Gan

    2014-01-01

    Full Text Available Well-defined image can assist user to identify region of interest during segmentation. However, complex medical image is usually characterized by poor tissue contrast and low background luminance. The contrast improvement can lift image visual quality, but the fundamental contrast enhancement methods often overlook the sudden jump problem. In this work, the proposed bihistogram Bezier curve contrast enhancement introduces the concept of “adequate contrast enhancement” to overcome sudden jump problem in knee magnetic resonance image. Since every image produces its own intensity distribution, the adequate contrast enhancement checks on the image’s maximum intensity distortion and uses intensity discrepancy reduction to generate Bezier transform curve. The proposed method improves tissue contrast and preserves pertinent knee features without compromising natural image appearance. Besides, statistical results from Fisher’s Least Significant Difference test and the Duncan test have consistently indicated that the proposed method outperforms fundamental contrast enhancement methods to exalt image visual quality. As the study is limited to relatively small image database, future works will include a larger dataset with osteoarthritic images to assess the clinical effectiveness of the proposed method to facilitate the image inspection.

  1. Delayed contrast-enhanced computed tomography in patients with known or suspected cardiac sarcoidosis: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Aikawa, Tadao; Naya, Masanao; Obara, Masahiko [Hokkaido University Graduate School of Medicine, Sapporo (Japan); Oyama-Manabe, Noriko; Kudo, Kohsuke [Hokkaido University Hospital, Department of Diagnostic and Interventional Radiology, Sapporo (Japan); Ohira, Hiroshi; Sugimoto, Ayako; Tsujino, Ichizo [Hokkaido University Graduate School of Medicine, First Department of Medicine, Sapporo (Japan); Manabe, Osamu; Tamaki, Nagara [Hokkaido University Graduate School of Medicine, Department of Nuclear Medicine, Sapporo (Japan); Tsutsui, Hiroyuki [Kyushu University, Department of Cardiovascular Medicine, Fukuoka (Japan)

    2017-10-15

    To evaluate the diagnostic value of delayed contrast-enhanced computed tomography (DE-CT) for cardiac sarcoidosis (CS) in patients with or without implantable devices, including a quantitative comparison with late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Twenty-four patients (mean age, 64 ± 9 years; 17 women) with known or suspected CS underwent retrospective electrocardiogram-gated DE-CT at 80 kV with knowledge-based iterative model reconstruction. Fourteen patients without implantable devices also underwent LGE-CMR, while ten with pacemakers or implantable cardioverter-defibrillators did not. The presence of hyperenhanced myocardium was assessed visually and quantitatively using a 5-standard deviation threshold above the mean of remote myocardium. Inter-observer agreement for visual detection of hyperenhanced segments on DE-CT was excellent in patients with implantable devices and in those without (κ = 0.91 and κ = 0.94, respectively). Comparisons of the percent area of hyperenhanced myocardium between DE-CT and LGE-CMR on both per-patient and per-segment analyses showed good correlations (r = 0.96 and r = 0.83, respectively; p < 0.001). The sensitivity and specificity of DE-CT for the diagnosis of CS were 94% and 33%. The extent of hyperenhanced lesion with DE-CT showed good agreement with LGE-CMR results. DE-CT showed high sensitivity for detecting CS and may be useful particularly in patients with contraindications to CMR. (orig.)

  2. Contrast-enhanced MR imaging of the endolymphatic sac in patients with sudden hearing loss

    Energy Technology Data Exchange (ETDEWEB)

    Naganawa, Shinji; Koshikawa, Tokiko; Fukatsu, Hiroshi; Ishigaki, Takeo [Department of Radiology, Nagoya University School of Medicine (Japan); Nakashima, Tsutomu [Department of Otolayngology, Nagoya University School of Medicine (Japan); Ichinose, Nobuyasu [Toshiba Nasu Operations, Tochigi (Japan)

    2002-05-01

    Our objective was to evaluate the frequency of contrast enhancement of the endolymphatic sac in patients with sudden hearing loss. Forty consecutive patients with sudden sensorineural hearing loss (20 males and 20 females; age range 11-82 years), 40 age-matched control subjects, and 5 patients with Meniere's disease were examined using the same imaging protocol on a 1.5-T MR system. Pre- and post-contrast-enhanced T1-weighted 3D spoiled gradient-echo sequence (3D SPGR; TR/TE=23/10 ms, no. of excitations=1, flip angle=30 ) images were obtained using a voxel size of 0.6 x 0.7 x 0.8 mm{sup 3}. Contrast enhancement in the area of the endolymphatic sac was assessed by two radiologists, and the frequency of contrast enhancement was compared between the three study groups. Enhancement of the ipsilateral endolymphatic sac was observed in 30 of the 40 patients with sudden hearing loss (75%). Twenty of these 30 patients also showed enhancement on the contralateral side, and 1 patient showed enhancement only on the contralateral side. Only 1 of the 5 patients with Meniere's disease showed enhancement. Nine of the 40 control subjects (22.5%) showed enhancement (bilateral enhancement in 5 subjects, unilateral in 4). The frequency of enhancement in patients with sudden hearing loss was significantly higher than that in control subjects (P<0.0001) or patients with Meniere's disease (P<0.05). The frequency of contrast enhancement of the endolymphatic sac is significantly increased in patients with sudden hearing loss, but further study is necessary to clarify the relationship between this finding and the pathophysiology of sudden hearing loss. (orig.)

  3. Contrast-enhanced 3D micro-CT of plant tissues using different impregnation techniques.

    Science.gov (United States)

    Wang, Zi; Verboven, Pieter; Nicolai, Bart

    2017-01-01

    X-ray micro-CT has increasingly been used for 3D imaging of plant structures. At the micrometer resolution however, limitations in X-ray contrast often lead to datasets with poor qualitative and quantitative measures, especially within dense cell clusters of plant tissue specimens. The current study developed protocols for delivering a cesium based contrast enhancing solution to varying plant tissue specimens for the purpose of improving 3D tissue structure characterization within plant specimens, accompanied by new image processing workflows to extract the additional data generated by the contrast enhanced scans. Following passive delivery of a 10% cesium iodide contrast solution, significant increases of 85.4 and 38.0% in analyzable cell volumes were observed in pear fruit hypanthium and tomato fruit outer mesocarp samples. A significant increase of 139.6% in the number of analyzable cells was observed in the pear fruit samples along the added ability to locate and isolate better brachysclereids and vasculature in the sample volume. Furthermore, contrast enhancement resulted in significant improvement in the definition of collenchyma and parenchyma in the petiolule of tomato leaflets, from which both qualitative and quantitative data can be extracted with respect to cell measures. However, contrast enhancement was not achieved in leaf vasculature and mesophyll tissue due to fundamental limitations. Active contrast delivery to apple fruit hypanthium samples did yield a small but insignificant increase in analyzable volume and cells, but data on vasculature can now be extracted better in correspondence to the pear hypanthium samples. Contrast delivery thus improved visualization and analysis the most in dense tissue types. The cesium based contrast enhancing protocols and workflows can be utilized to obtain detailed 3D data on the internal microstructure of plant samples, and can be adapted to additional samples of interest with minimal effort. The resulting

  4. Guidance and monitoring of radiofrequency liver tumor ablation with contrast-enhanced ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Solbiati, Luigi [Department of Radiology, General Hospital, P. le Solaro 3, 21052 Busto Arsizio, VA (Italy)]. E-mail: lsolbiati@aobusto.it; Ierace, Tiziana [Department of Radiology, General Hospital, P. le Solaro 3, 21052 Busto Arsizio, VA (Italy); Tonolini, Massimo [Department of Radiology, General Hospital, P. le Solaro 3, 21052 Busto Arsizio, VA (Italy); Cova, Luca [Department of Radiology, General Hospital, P. le Solaro 3, 21052 Busto Arsizio, VA (Italy)

    2004-06-01

    Radiofrequency (RF) treatments of non-resectable hepatic tumors are generally guided with real-time sonography, which, however, cannot differentiate necrotic changes from viable tumor. To achieve complete treatment of hepatic tumors, accurate imaging techniques are needed for close treatment follow-up. Usually contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) are used; however, they can be performed only at the end of treatment sessions. In this field, contrast-enhanced ultrasound (CEUS) has shown to improve the sensitivity of plain ultrasonography. Recently, further developments of contrast-enhanced US technique have significantly increased its clinical utility. Continuous mode, low MI scans performed with harmonic imaging and contrast specific software appears as a very useful technique for the visualization of both macro- and microcirculation with depiction of tumor vascularisation. In our hospital, we have been employing contrast-enhanced sonography with sulphur hexaflouride microbubbles (SonoVue[reg], Bracco, Italy) before, during and immediately at the end of RF ablation procedures to monitor and assess the therapeutic result prior to closing the treatment session. The results obtained in a group of 109 patients with hepatocellular carcinoma (HCC) in liver cirrhosis (192 lesions) and in 53 patients with liver metastases (97 lesions) undergoing a single session of percutaneous RF tumor ablation, showed that the sensitivity of CEUS for the detection of residual tumor was almost equivalent to that of contrast-enhanced helical CT. More importantly, since the introduction of intraoperative CEUS the rate of partially unablated tumors has dropped from 16.1 to 5.9%. Cost-effectiveness and reduction of patients' discomfort related to the need of re-treatment are the two most outstanding advantages of CEUS in this field.

  5. Pelvic congestion syndrome initially detected by contrast enhanced F 18 FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Weung; Kim, Myoung Hyoung; Kim, Woo Hyoung; Kim, Chang Guhn [Wonkwang Univ. School of Medicine, Iksan (Korea, Republic of)

    2012-03-15

    Pelvic congestion syndrome (PCS) is said to occur as a result of retrograde flow in an incompetent ovarian vein. Ovarian vein incompetence is seen in approximately 10% of women, and up to 60% with this abnormality can develop PCS. The etiology of PCS is poorly understood and is likely to be multifactorial. Absence of ovarian vein valves is an important factor in its development. The causes of ovarian varicoceles are multifactorial, involving both mechanical and hormonal factors. Dilatation of the ovarian veins can result in vascular incompetence and retrograde blood flow. On either CT or magnetic resonance (MR) imaging studies, pelvic varices in PCS appear as dilated, tortuous, enhancing tubular structures near the ovaries and uterus. In addition, the extension of varices to the broad ligament and paravaginal venous plexus can be appreciated. With CT, the tubular nature of these structures and the pattern of enhancement after intravenous contrast medium administration distinguish them from lymphadenopathy or adnexal masses. Unlike such masses, pelvic varices appear isodense with other veins after contrast enhancement. Contrast enhanced CT data as part of the combined PET/CT examination provide additional information when compared with non enhanced PET/CT. Because CT data supply the anatomic background for PET, the most important benefit relates to more precise anatomic localization of pathology by differentiation of the lesion from its surrounding structures. By supporting lesion detection and characterization, CT contrast agents can be of additional value in F 18 FDG non avid disease. As in the presented case, careful review of CT images in contrast enhanced PET/CT enables the detection of F 18 FDG non avid disease such as PCS. As contrast enhanced F 18 FDG PET/CT had been performed frequently, being familiar with the findings of PCS on the contrast enhanced CT images would have been helpful for the nuclear medicine physicians.

  6. The value of contrast-enhanced CT scan in prediction of development of contusional hemorrhage

    International Nuclear Information System (INIS)

    Yokoyama, Kazuhiro; Kyoi, Kikuo; Sakaki, Toshisuke; Kinugawa, Kazuhiko; Morimoto, Tetsuya

    1983-01-01

    It is often experienced that even if there are no significant findings on the initial plain CT scan in the patient with cerebral contusion, the patient has thereafter a serious clinical course and requires emergency operation for so-called contusional hemorrhage. In order to predict of the development of contusional hemorrhage we performed contrast-enhanced CT scan at the time of patient's arrival within 12 hours after injury, if there was cerebral contusion on the initial plain CT scan, and repeated plain CT scan 24 hours after the contrast-enhanced CT scan. If enhancement was demonstrated on the contrastenhanced CT scan, we predicted the development of contusional hemorrhage and if not demonstrated, we predicted no more development of contusional hemorrhage and then we studied the correlation between the prediction and the plain CT 24 hours after the contrast-enhanced CT scan. The results were as follows: 1) The prediction was correct in 13 cases out of 16 cases in which the development of contusional hemorrhage was observed. In 18 cases where no development of contusional hemorrhage was observed, the prediction was correct without exception. 2) Most of the cases in which enhancement was demonstrated were ones examined not before 3 hours after injury. 3) The extent of enhancement shown on contrastenhanced CT scan was well consistent with that of contusional hemorrhage on the plain CT scan 24 hours after the contrast-enhanced CT scan. From these results, the contrast-enhanced CT scan in acute stage of head injury was considered to by very useful in prediction of the development of contusional hemorrhage. (author)

  7. Contrast-enhanced color Doppler US in breast cancer: Tumoral vascularity correlated with angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun A; Yoon, Kwon Ha; Yun, Ki Jung; Lee, Kwang Man; Park, Ki Han; Juhng, Seon Kwan; Won, Jong Jin [Wonkwang University School of Medicine, Seoul (Korea, Republic of)

    2000-12-15

    To evaluate the effects of contrast-enhanced color Doppler ultrasonography (CDUS) on the depiction of vascularity and flow pattern in breast cancer and to determine the relationship between tumoral vascularity and angiogenesis. Twenty-one patients with breast cancer were prospectively evaluated with CDUS before and after injection of the contrast agent (SH U 508A, 2.5g, 300 mg/ml ). The tumoral vascularity was expressed as percentage of color Doppler area, which was measured quantitatively by a computerized program (Ultrasonic Imaging Tool; Soongsil University, Seoul, Korea). The flow pattern (four-patterns; spotty, linear, branching, marginal) of the vascularity was analyzed. After surgery, tumor angiogenesis was assessed by microvessel density. The relationship between the vascularity on CDUS and microvessel density was statistically analyzed. At unenhanced CDUS, tumoral flow signals were detected in 12 lesions (48%); at contrast-enhanced CDUS, 18 lesions (86%). All These 18 lesions showed increased signals, compared with those at unenhanced CDUS. The percentage color Doppler area was 1.86 {+-} 0.48% at unenhanced CDUS and 5.23 {+-} 1.18% at contrast-enhanced CDUS. The flow patterns before contrast injection were spotty pattern in 11 tumors and linear pattern in one; after contrast injection, spotty in 8, linear in 4, branching in 5, and marginal in one. The tumoral vascularity at contrast-enhanced CDUS showed no significant correlation with microvessel density. Contrast-enhanced CDUS seems to be a valuable tool in the depiction of vascularity and characterization of flow pattern in breast cancer. However, tumoral vascularity on CDUS may not reflect tumoral angiogenesis.

  8. Evaluation of adverse events and imaging quality in contrast-enhanced abdominal CT using generic CT contrast developed in South Korea: A multicenter prospective observational study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, You Sung [Dept. of Radiology, Ilsan Paik Hospital, College of Medicine, Inje University, Goyang (Korea, Republic of); Jung, Seung Eun; Park, Micheal Yong; Rha, Sung Eun [Dept. of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of); Lee, Soo Rim [Dept. of Radiology, Uijeongbu St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu (Korea, Republic of); Hwang, Seong Su [Dept. of Radiology, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon (Korea, Republic of); Lim, Yeon Soo [Dept. of Radiology, Bucheon St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Bucheon (Korea, Republic of); Park, Jeong Mi [Dept. of Radiology, Yeouido St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2017-02-15

    The purpose of this study is to evaluate the clinical safety and usefulness of the Prosure®300 in contrast-enhanced abdominal CT. This prospective study was approved by our center's Institutional Review Board. This study included 727 patients in four hospitals who underwent contrast-enhanced abdominal CT using Prosure®300 from December 2010 to June 2011. Adverse events were classified into minor and major adverse events. Logistic regression analysis was used to evaluate the relationship between adverse events and patient gender, age, underlying disease, and amount of injected contrast agent. Two radiologists independently evaluated imaging quality as poor, insufficient, sufficient, good, or very good. One hundred seventy-six out of 727 patients complained of adverse events, but most of them were minor adverse events. Five patients complained of dyspnea and one patient had hoarseness, but recovered without treatment. The rate of adverse events was significantly higher in men (p = 0.011), and a greater amount of injected contrast agent was related to a higher rate of adverse events (p = 0.000). Imaging quality was evaluated as 'good' or 'very good' in all cases. Prosure®300, a generic CT contrast agent developed in South Korea, can be used in contrast-enhanced abdominal CT.

  9. Liver haemangiomas undetermined at grey-scale ultrasound: contrast-enhancement patterns with SonoVue and pulse-inversion US.

    Science.gov (United States)

    Bartolotta, Tommaso Vincenzo; Midiri, Massimo; Quaia, Emilio; Bertolotto, Michele; Galia, Massimo; Cademartiri, Filippo; Lagalla, Roberto

    2005-04-01

    The objective of this study was to describe the spectrum of contrast-enhancement patterns of hepatic haemangiomas undetermined at grey-scale ultrasound (US) on SonoVue-enhanced pulse-inversion (PI) US. Twenty patients (11 women, nine men) with 35 haemangiomas (size range: 1-7 cm; mean: 3.1 cm) undetermined at baseline US underwent PI at low M.I. (0.05-0.08) after i.v. injection of SonoVue. All haemangiomas were confirmed by typical helical computed tomography (CT) and/or magnetic resonance imaging (MRI) findings. US examinations were videotaped and then reviewed by two experienced radiologists blinded to the final diagnosis. Readers evaluated by consensus the baseline echogenicity and the dynamic enhancement pattern of each lesion, in comparison with adjacent liver parenchyma. After administration of SonoVue, 31/35 (88%) haemangiomas showed peripheral hyperechoic nodules in the arterial phase, followed by progressive centripetal fill-in, which was complete in 25/35 cases and incomplete in 6/35 cases. Three out of 35 (9%) haemangiomas showed rapid and complete fill-in in the arterial phase, which persisted in the portal and delayed phases. Finally, 1/35 haemangiomas (3%) showed a rim of arterial contrast enhancement with progressive and complete centripetal fill-in in portal-venous and delayed phases. In conclusion, PI after the administration of SonoVue enabled the depiction of typical contrast-enhancement patterns in haemangiomas undetermined at baseline US.

  10. Comparison of contrast-enhanced spiral CT scan and pulmonary angiography in diagnosing pulmonary embolism: an experimental study in pig models

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyae Young; Lee, Sun Wha [Ewha Womans University Mokdong Hospital, Seoul (Korea, Republic of); Im, Jung Gi; Goo, Jin Mo; Seo, Joon Beom; Park, Sun Won; Lee, Whal [Seoul National University College of Medicine and the Institute of Radiation Medicine, Seoul (Korea, Republic of)

    2000-01-01

    The purpose of our study was to compare the diagnostic value of contrast-enhanced spiral CT scanning and pulmonary angiography in detecting central and peripheral pulmonary embolism (PE) in pigs. Experiments were performed in a porcine model of acute pulmonary embolism. Five pigs underwent contrast-enhanced spiral CT and pulmonary angiography after central venous administration of embolic material (Konyak). Three thoracic radiologists read the films and the results were compared with the findings of pathologic specimens. Of 85 cases of PE detected pathologically, 78 (91.8%) were visible with spiral CT and 65 (76.5%) with pulmonary angiography. Sensitivity and specificity for the detection of central emboli were 95% and 100%, respectively, with spiral CT, and 89% and 100%, respectively, with pulmonary angiography. Sensitivity and specificity for the detection peripheral emboli were 88% and 99%, respectively, with spiral CT, and 64% and 100%, respectively, with pulmonary angiography. Contrast-enhanced spiral CT is a very useful method for the diagnosis of both peripheral and central pulmonary embolism. Compared to pulmonary angiography its sensitivity and specificity are high. (author)

  11. Clinical validation of semi-automated software for volumetric and dynamic contrast enhancement analysis of soft tissue venous malformations on magnetic resonance imaging examination

    Energy Technology Data Exchange (ETDEWEB)

    Caty, Veronique [Hopital Maisonneuve-Rosemont, Universite de Montreal, Department of Radiology, Montreal, QC (Canada); Kauffmann, Claude; Giroux, Marie-France; Oliva, Vincent; Therasse, Eric [Centre Hospitalier de l' Universite de Montreal (CHUM), Universite de Montreal and Research Centre, CHUM (CRCHUM), Department of Radiology, Montreal, QC (Canada); Dubois, Josee [Centre Hospitalier Universitaire Sainte-Justine et Universite de Montreal, Department of Radiology, Montreal, QC (Canada); Mansour, Asmaa [Institut de Cardiologie de Montreal, Heart Institute Coordinating Centre, Montreal, QC (Canada); Piche, Nicolas [Object Research System, Montreal, QC (Canada); Soulez, Gilles [Centre Hospitalier de l' Universite de Montreal (CHUM), Universite de Montreal and Research Centre, CHUM (CRCHUM), Department of Radiology, Montreal, QC (Canada); CHUM - Hopital Notre-Dame, Department of Radiology, Montreal, Quebec (Canada)

    2014-02-15

    To evaluate venous malformation (VM) volume and contrast-enhancement analysis on magnetic resonance imaging (MRI) compared with diameter evaluation. Baseline MRI was undertaken in 44 patients, 20 of whom were followed by MRI after sclerotherapy. All patients underwent short-tau inversion recovery (STIR) acquisitions and dynamic contrast assessment. VM diameters in three orthogonal directions were measured to obtain the largest and mean diameters. Volumetric reconstruction of VM was generated from two orthogonal STIR sequences and fused with acquisitions after contrast medium injection. Reproducibility (interclass correlation coefficients [ICCs]) of diameter and volume measurements was estimated. VM size variations in diameter and volume after sclerotherapy and contrast enhancement before sclerotherapy were compared in patients with clinical success or failure. Inter-observer ICCs were similar for diameter and volume measurements at baseline and follow-up (range 0.87-0.99). Higher percentages of size reduction after sclerotherapy were observed with volume (32.6 ± 30.7 %) than with diameter measurements (14.4 ± 21.4 %; P = 0.037). Contrast enhancement values were estimated at 65.3 ± 27.5 % and 84 ± 13 % in patients with clinical failure and success respectively (P = 0.056). Venous malformation volume was as reproducible as diameter measurement and more sensitive in detecting therapeutic responses. Patients with better clinical outcome tend to have stronger malformation enhancement. (orig.)

  12. Evaluation of adverse events and imaging quality in contrast-enhanced abdominal CT using generic CT contrast developed in South Korea: A multicenter prospective observational study

    International Nuclear Information System (INIS)

    Kim, You Sung; Jung, Seung Eun; Park, Micheal Yong; Rha, Sung Eun; Lee, Soo Rim; Hwang, Seong Su; Lim, Yeon Soo; Park, Jeong Mi

    2017-01-01

    The purpose of this study is to evaluate the clinical safety and usefulness of the Prosure®300 in contrast-enhanced abdominal CT. This prospective study was approved by our center's Institutional Review Board. This study included 727 patients in four hospitals who underwent contrast-enhanced abdominal CT using Prosure®300 from December 2010 to June 2011. Adverse events were classified into minor and major adverse events. Logistic regression analysis was used to evaluate the relationship between adverse events and patient gender, age, underlying disease, and amount of injected contrast agent. Two radiologists independently evaluated imaging quality as poor, insufficient, sufficient, good, or very good. One hundred seventy-six out of 727 patients complained of adverse events, but most of them were minor adverse events. Five patients complained of dyspnea and one patient had hoarseness, but recovered without treatment. The rate of adverse events was significantly higher in men (p = 0.011), and a greater amount of injected contrast agent was related to a higher rate of adverse events (p = 0.000). Imaging quality was evaluated as 'good' or 'very good' in all cases. Prosure®300, a generic CT contrast agent developed in South Korea, can be used in contrast-enhanced abdominal CT

  13. Diffusion-weighted imaging versus contrast-enhanced MR imaging for the differentiation of renal oncocytomas and chromophobe renal cell carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Yan; Wang, Haiyi; Shen, Yanguang; Ma, Lu; Pan, Jingjing; Ye, Huiyi [Chinese PLA General Hospital, Department of Radiology, Beijing (China); Guo, Aitao [Chinese PLA General Hospital, Department of Pathology, Beijing (China); Wang, Jia [Handan Central Hosptical, Department of Radiology, Hebei (China); Kang, Suhai [264 Hospital of PLA, X-ray Department, Taiyuan (China)

    2017-12-15

    To compare the performance of diffusion-weighted imaging (DWI) with that of contrast-enhanced MRI in differentiating renal oncocytomas from chromophobe renal cell carcinomas (RCCs). We recruited 48 patients with histopathologically confirmed renal oncocytomas (n=16) and chromophobe RCCs (n=32). All patients underwent preoperative DWI and contrast-enhanced MRI. Apparent diffusion coefficient (ADC) and signal intensity were measured in each patient. ADC ratio and percentage of signal intensity change were calculated. Mean ADC values for renal oncocytomas were significantly higher than those for chromophobe RCCs (1.59±0.21 vs. 1.09±0.29 x 10{sup -3} mm{sup 2}/s, p < 0.001). Area under the ROC curve, sensitivity and specificity were 0.931, 87.5% and 84.4%, respectively, for ADC measurement of DW imaging; 0.825, 87.5% and 75%, respectively, for enhancement ratio (p > 0.05). Adding ADC values to the enhancement ratios in the ROC, analysis to differentiate renal oncocytoma from chromophobe RCCs increased specificity from 75 to 87.5% at 87.5% sensitivity without significantly increasing the AUC (0.930). Both DWI and contrast-enhanced MRI may assist in differentiating renal oncocytomas from chromophobe RCCs, with DWI showing higher diagnostic value. The combination of the two parameters could potentially provide better performance in distinguishing these two tumours. (orig.)

  14. Diagnosis value of dual-phase contrast enhancement CT combined with virtual non-enhanced images by dual-energy CT in clear cell renal cell carcinoma

    International Nuclear Information System (INIS)

    Ma Zhoupeng; Zhou Jianjun; Liu Xueling; Wang Chun; Zhang Shunzhuang

    2012-01-01

    Objective: To explore the diagnostic value of dual-phase contrast enhancement CT combined with virtual non-enhanced images by dual-energy CT in clear cell renal cell carcinoma. Methods: Sixty patients who were suspected of clear cell renal cell carcinoma underwent non-enhanced CT and contrast enhancement CT of early interface-phase between cortex -medulla and parenchymal phase on a dual-energy CT. The true non-enhanced kidney CT (TNCT) was performed in a single-energy acquisition mode, but the dual-phase contrast enhancement CT were performed in a dual-energy mode of 80 kV and 140 kV respectively. The virtual non-enhanced CT (VNCT) images were derived from the data of early interface phase using liver virtual non-contrast software. The diagnose according to VNCT combined dual-phase contrast enhancement CT and dual-phase contrast enhancement CT only were made respectively and compared with χ 2 test. Between the true non-contrast CT and the virtual non-contrast CT, the image quality was compared with Wilcoxon test; The radiation dose of volume CT dose index (CTDIvol) and dose length product(DLP) in a single-phase and total examination, the mean CT HU values of the tumours were compared with t test. Results: The accuracy of VNCT combined dual-phase contrast enhancement CT was higher than that of dual-phase contrast enhancement CT only [93.3% (56/60) vs.78.3% (47/60); χ 2 =5.6, P<0.05]. The detective ability (score) of VNCT was near to that of TNCT and the difference was not obvious (Z=0.00, P>0.05). The radiation dose of volume CT dose index (CTDIvol) and dose length product (DLP) in a single phase and total examination of VNCT [(8.85 ± 1.28) mGy, (196.45 ±21.12) mGy·cm, (17.69±2.35) mGy, (392.90±42.25) mGy · cm] were lower than that of TNCT [(10.20 ± 1.44) mGy,(218.29 ± 29.60) mGy · cm, (30.61 ± 3.27) mGy and (654.86 ± 88.81) mGy ·cm], t=4.21, 3.58, 23.63, 16.12 respectively, P<0.05. The mean CT HU values of tumours on VNCT images was higher than that

  15. Utility of dynamic contrast-enhanced magnetic resonance imaging for differentiating glioblastoma, primary central nervous system lymphoma and brain metastatic tumor

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Shanshan, E-mail: lushan1118@163.com [Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province (China); Gao, Qianqian, E-mail: gaoqian123011@163.com [Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province (China); Yu, Jing, E-mail: yujing0303@163.com [Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province (China); Li, Yang, E-mail: yuhao040511@163.com [Department of Pathology,The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province (China); Cao, Peng, E-mail: peng.cao@ge.com [GE healthcare, Shanghai (China); Shi, Haibin, E-mail: hbshi346@163.com [Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province (China); Hong, Xunning, E-mail: hongxunning@sina.com [Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province (China)

    2016-10-15

    Purpose: The study aimed to investigate the use of dynamic contrast-enhanced magnetic resonance imaging (MRI)-derived permeability parameters for the differentiation of glioblastoma multiformes (GBMs), primary central nervous system lymphomas (PCNSLs), and brain metastatic tumors (MTs). Materials and methods: Seventy-five patients with histopathologically confirmed GBMs (n = 38), PCNSLs (n = 16) and MTs (n = 21) underwent dynamic contrast-enhanced MRIs before surgery. The volume transfer constant K{sup trans}, the flux rate constant between extravascular extracellular space and plasma K{sub ep}, the extravascular extracellular volume V{sub e} and the fractional plasma volume V{sub p} were measured within the entire contrast-enhancing tumor by extended Tofts model. A one-way analysis of variance was used to compare all of the parameters among these three tumors, followed by the post-hoc test. Receiver operating characteristic curves were constructed to evaluate the diagnostic performance of the permeability parameters. Results: Mean K{sup trans} value and V{sub e} value were significantly higher in PCNSLs than in GBMs (P < 0.001 and P = 0.011) and MTs (P < 0.001 and P < 0.001). No significant difference was observed in all of the permeability parameters between GBMs and MTs. According to the receiver operating characteristic analyses, both K{sup trans} and V{sub e} had good diagnostic performance for discriminating between PCNSLs and GBMs (the area under the curve: 0.847 and 0.785, respectively), as well as between PCNSLs and MTs (the area under the curve: 0.851 and 0.884, respectively). Conclusions: The K{sup trans} and V{sub e} derived from dynamic contrast-enhanced MRI facilitate the differentiation of PCNSLs from GBMs and MTs.

  16. Calcium Scoring of Aortic Valve Calcification in Aortic Valve Stenosis with a Multislice Computed Tomography Scanner: Non-enhanced versus Contrast-enhanced Studies

    International Nuclear Information System (INIS)

    Muehlenbruch, G.

    2005-01-01

    Purpose: Previous studies have shown a positive correlation between amount of aortic valve calcification (AVC) and degree of aortic valve stenosis (AVS). We have investigated whether calcium scoring of AVC from contrast-enhanced images is reliable. Material and Methods: Nineteen patients with suspected AVS underwent retrospectively ECG-gated multislice computed tomography (MSCT). Standardized scan protocols were applied prior to (120 KV, 133 mAseff) and after (120 KV, 500 mAseff) the administration of non-ionic contrast material. Image reconstruction was performed at 60% of the RR interval (slice thickness 3 mm, reconstruction increment 2 mm). AVC was quantified using Agatston score and calcium mass. The number of lesions was calculated. All non-enhanced images were scored using thresholds of 130 HU and 350 HU. Contrast-enhanced images were assessed with a threshold of 350 HU exclusively. Results: Fifteen patients with AVCs were included in the statistical analysis. The mean Agatston score (calcium mass) in non-enhanced images was 2888.4±2844.4 (694.2 mg±869.3 mg). Altering the threshold from 130 HU to 350 HU led to a 58.2% (30.5%) decrease in the AVC score ( P values <0.001). Contrast-enhanced images showed an increased Agatston score (calcium mass) of 56.2% (33.5%) compared to non-enhanced images ( P values <0.05) with the same threshold of 350 HU. Conclusion: Quantification of AVC from contrast-enhanced images is not reliable, as contrast material simulates calcification

  17. Usefulness of dynamic contrast enhanced lumbar spine MR imaging postoperative herniated lumbar disc

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ji Eun; Chung, Tae Sub; Kim, Young Soo; Cho, Yong Eun; Park, Mi Suk [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1999-02-01

    To compare the usefulness of dynamic contrast enhanced lumbar spine MR imaging with that of conventional delayed contrast enhanced MR imaging in the assessment of postoperative herniated lumbar disc. Forty-one postoperative herniated lumbar disc (HLD) lesions of 32 patients with back pain were examined with MR imaging (1.5T, Vision, Siemens, Germany). Five-phase dynamic 2D FLASH sagittal images (TR/TE = 118.1msec/4.1msec) were obtained every 19 seconds with a 4 minutes delayed image after contrast injection. As seen on delayed images, the discs were assessed as recurred, fibrosis, or no change. On dynamic images, the pattern of enhancement was evaluated as follows : Type 1 (no change in peripheral disc enhancement between the early and late phases) ; or Type 2 (minimal internal extension of marginal smooth enhancement during the late phase) ; or Type 3 (marked internal extension of peripheral irregular enhancement). Dynamic and delayed imaging were compared, and early epidural space enhancement with rapid wash-out was also evaluated. Of 41 postoperative HLDs, 39 lesions showed peripheral contrast enhancement. Evaluation depended on delayed imaging, and was as follows : recurred HLD (n=27) ; fibrosis (n=5) ; no change in postoperative disc (n=7). On dynamic contrast-enhanced imaging, enhancement patterns were Type 1 (n=29), Type 2 (n=7), and Type 3 (n=3). In 29 Type 1 lesions, there were no significant differences in image findings between dynamic and delayed images. However, in ten lesions (type 2 : n=7, type 3 : n=3), findings additional to those revealed by delayed images were demonstrated by dynamic contrast-enhanced MR imaging. Nine of the ten Type 2 and 3 lesions were diagnosed as recurred HLD. On dynamic images, five lesions showed early epidural space enhancement. Dynamic contrast-enhanced lumbar spine MR imaging provided additional findings such as increased peripheral disc enhancement, and epidural space enhancement, which cannot be detected on

  18. Contrast-enhanced MR 3D angiography in the assessment of brain AVMs

    International Nuclear Information System (INIS)

    Unlu, Ercument; Temizoz, Osman; Albayram, Sait; Genchellac, Hakan; Hamamcioglu, M. Kemal; Kurt, Imran; Demir, M. Kemal

    2006-01-01

    Background and purpose: Digital subtraction angiography (DSA) is the current reference standard for the diagnosis, assessment, and management of brain arteriovenous malformations (AVMs). The purpose of this study was to compare the diagnostic utility of three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) and contrast-enhanced 3D MRA in patients with intracranial arteriovenous malformations (AVMs) in different sizes and locations. The AVM diagnosis was proved via DSA and almost half of the patients had also hematoma. Materials and methods: Two radiologists, experienced on neurovascular imaging and independent from each other, retrospectively reviewed two MRA techniques and DSA with regard to the assessment of feeding arteries, AVM nidus, and venous drainage patterns on 20 patients with 23 examinations by scoring system. Disagreements were resolved by consensus. Results: An excellent agreement between contrast-enhanced MRA and DSA was found in order to assess the numbers of arterial feeders and draining veins (Spearman r = 0.913, P < 0.001). The average scores in contrast-enhanced MRA for feeders, nidi, and drainers were respectively 2.26, 2.69, and 2.48, while in TOF-MRA they are 1.96, 1.35, and 0.89, respectively. Conclusion: Compared to TOF-MRA, 3D contrast-enhanced MRA is useful for visualization by subtraction technique of malformation components presented by hematoma or by haem product. On the other hand, for the cases presented by slow or complex flow that is especially in around or nidi or around the venous portion is also advantageous because of the independence from flow-related enhancement. Therapeutic effects were clearly demonstrated in three follow-up patients. A major limitation of this technique is the low spatial resolution. Since there is such a limitation, arterial feeder of a case with micro-AVM is not detected by contrast-enhanced MRA and nidus for the same case was observed retrospectively. In this respect, we

  19. Contrast-enhanced MR 3D angiography in the assessment of brain AVMs

    Energy Technology Data Exchange (ETDEWEB)

    Unlu, Ercument [Department of Radiology, Trakya University Medicine School, Edirne (Turkey)]. E-mail: drercument@yahoo.com; Temizoz, Osman [Department of Radiology, Trakya University Medicine School, Edirne (Turkey); Albayram, Sait [Department of Radiology, Istanbul University, Cerrahpasa Medicine School, Istanbul (Turkey); Genchellac, Hakan [Department of Radiology, Trakya University Medicine School, Edirne (Turkey); Hamamcioglu, M. Kemal [Department of Neurosurgery, Trakya University Medicine School, Edirne (Turkey); Kurt, Imran [Department of Biostatistics, Trakya University Medicine School, Edirne (Turkey); Demir, M. Kemal [Department of Radiology, Trakya University Medicine School, Edirne (Turkey)

    2006-12-15

    Background and purpose: Digital subtraction angiography (DSA) is the current reference standard for the diagnosis, assessment, and management of brain arteriovenous malformations (AVMs). The purpose of this study was to compare the diagnostic utility of three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) and contrast-enhanced 3D MRA in patients with intracranial arteriovenous malformations (AVMs) in different sizes and locations. The AVM diagnosis was proved via DSA and almost half of the patients had also hematoma. Materials and methods: Two radiologists, experienced on neurovascular imaging and independent from each other, retrospectively reviewed two MRA techniques and DSA with regard to the assessment of feeding arteries, AVM nidus, and venous drainage patterns on 20 patients with 23 examinations by scoring system. Disagreements were resolved by consensus. Results: An excellent agreement between contrast-enhanced MRA and DSA was found in order to assess the numbers of arterial feeders and draining veins (Spearman r = 0.913, P < 0.001). The average scores in contrast-enhanced MRA for feeders, nidi, and drainers were respectively 2.26, 2.69, and 2.48, while in TOF-MRA they are 1.96, 1.35, and 0.89, respectively. Conclusion: Compared to TOF-MRA, 3D contrast-enhanced MRA is useful for visualization by subtraction technique of malformation components presented by hematoma or by haem product. On the other hand, for the cases presented by slow or complex flow that is especially in around or nidi or around the venous portion is also advantageous because of the independence from flow-related enhancement. Therapeutic effects were clearly demonstrated in three follow-up patients. A major limitation of this technique is the low spatial resolution. Since there is such a limitation, arterial feeder of a case with micro-AVM is not detected by contrast-enhanced MRA and nidus for the same case was observed retrospectively. In this respect, we

  20. Deep learning enables reduced gadolinium dose for contrast-enhanced brain MRI.

    Science.gov (United States)

    Gong, Enhao; Pauly, John M; Wintermark, Max; Zaharchuk, Greg

    2018-02-13

    There are concerns over gadolinium deposition from gadolinium-based contrast agents (GBCA) administration. To reduce gadolinium dose in contrast-enhanced brain MRI using a deep learning method. Retrospective, crossover. Sixty patients receiving clinically indicated contrast-enhanced brain MRI. 3D T 1 -weighted inversion-recovery prepped fast-spoiled-gradient-echo (IR-FSPGR) imaging was acquired at both 1.5T and 3T. In 60 brain MRI exams, the IR-FSPGR sequence was obtained under three conditions: precontrast, postcontrast images with 10% low-dose (0.01mmol/kg) and 100% full-dose (0.1 mmol/kg) of gadobenate dimeglumine. We trained a deep learning model using the first 10 cases (with mixed indications) to approximate full-dose images from the precontrast and low-dose images. Synthesized full-dose images were created using the trained model in two test sets: 20 patients with mixed indications and 30 patients with glioma. For both test sets, low-dose, true full-dose, and the synthesized full-dose postcontrast image sets were compared quantitatively using peak-signal-to-noise-ratios (PSNR) and structural-similarity-index (SSIM). For the test set comprised of 20 patients with mixed indications, two neuroradiologists scored blindly and independently for the three postcontrast image sets, evaluating image quality, motion-artifact suppression, and contrast enhancement compared with precontrast images. Results were assessed using paired t-tests and noninferiority tests. The proposed deep learning method yielded significant (n = 50, P 5 dB PSNR gains and >11.0% SSIM). Ratings on image quality (n = 20, P = 0.003) and contrast enhancement (n = 20, P < 0.001) were significantly increased. Compared to true full-dose images, the synthesized full-dose images have a slight but not significant reduction in image quality (n = 20, P = 0.083) and contrast enhancement (n = 20, P = 0.068). Slightly better (n = 20, P = 0.039) motion

  1. Technical aspects of contrast-enhanced magnetic resonance imaging of the breast: literature review

    International Nuclear Information System (INIS)

    Leopoldino, Denise de Deus; Gracio, Tatiana Schiller; D'Ippolito, Giuseppe; Bezerra, Alexandre Sergio de Araujo; Gracio, Tatiana Schiller

    2005-01-01

    With the advances in surface coil technology and the development of new imaging protocols in addition to the increase of the use of contrast agents, contrast enhanced magnetic resonance imaging (MRI) has emerged as a promising modality for detection, diagnosis and staging of breast cancer. Despite these advances, there are some unresolved issues, including no defined standard technique for contrast-enhanced breast MRI and no standard criteria of interpretation for the evaluation of such studies. In this article, we review the literature and discuss the general requirements and recommendations for contrast agent-enhanced breast MRI, including image interpretation criteria, MR equipment, dedicated radiofrequency coils, use of paramagnetic contrast agents, fat-suppression techniques, planes of acquisition, pulse sequence specifications and artifact sources. (author)

  2. Feature and Contrast Enhancement of Mammographic Image Based on Multiscale Analysis and Morphology

    Directory of Open Access Journals (Sweden)

    Shibin Wu

    2013-01-01

    Full Text Available A new algorithm for feature and contrast enhancement of mammographic images is proposed in this paper. The approach bases on multiscale transform and mathematical morphology. First of all, the Laplacian Gaussian pyramid operator is applied to transform the mammography into different scale subband images. In addition, the detail or high frequency subimages are equalized by contrast limited adaptive histogram equalization (CLAHE and low-pass subimages are processed by mathematical morphology. Finally, the enhanced image of feature and contrast is reconstructed from the Laplacian Gaussian pyramid coefficients modified at one or more levels by contrast limited adaptive histogram equalization and mathematical morphology, respectively. The enhanced image is processed by global nonlinear operator. The experimental results show that the presented algorithm is effective for feature and contrast enhancement of mammogram. The performance evaluation of the proposed algorithm is measured by contrast evaluation criterion for image, signal-noise-ratio (SNR, and contrast improvement index (CII.

  3. Feature and contrast enhancement of mammographic image based on multiscale analysis and morphology.

    Science.gov (United States)

    Wu, Shibin; Yu, Shaode; Yang, Yuhan; Xie, Yaoqin

    2013-01-01

    A new algorithm for feature and contrast enhancement of mammographic images is proposed in this paper. The approach bases on multiscale transform and mathematical morphology. First of all, the Laplacian Gaussian pyramid operator is applied to transform the mammography into different scale subband images. In addition, the detail or high frequency subimages are equalized by contrast limited adaptive histogram equalization (CLAHE) and low-pass subimages are processed by mathematical morphology. Finally, the enhanced image of feature and contrast is reconstructed from the Laplacian Gaussian pyramid coefficients modified at one or more levels by contrast limited adaptive histogram equalization and mathematical morphology, respectively. The enhanced image is processed by global nonlinear operator. The experimental results show that the presented algorithm is effective for feature and contrast enhancement of mammogram. The performance evaluation of the proposed algorithm is measured by contrast evaluation criterion for image, signal-noise-ratio (SNR), and contrast improvement index (CII).

  4. Automatic exact histogram specification for contrast enhancement and visual system based quantitative evaluation.

    Science.gov (United States)

    Sen, Debashis; Pal, Sankar K

    2011-05-01

    Histogram equalization, which aims at information maximization, is widely used in different ways to perform contrast enhancement in images. In this paper, an automatic exact histogram specification technique is proposed and used for global and local contrast enhancement of images. The desired histogram is obtained by first subjecting the image histogram to a modification process and then by maximizing a measure that represents increase in information and decrease in ambiguity. A new method of measuring image contrast based upon local band-limited approach and center-surround retinal receptive field model is also devised in this paper. This method works at multiple scales (frequency bands) and combines the contrast measures obtained at different scales using L(p)-norm. In comparison to a few existing methods, the effectiveness of the proposed automatic exact histogram specification technique in enhancing contrasts of images is demonstrated through qualitative analysis and the proposed image contrast measure based quantitative analysis.

  5. Power-constrained contrast enhancement for emissive displays based on histogram equalization.

    Science.gov (United States)

    Lee, Chulwoo; Lee, Chul; Lee, Young-Yoon; Kim, Chang-Su

    2012-01-01

    A power-constrained contrast-enhancement algorithm for emissive displays based on histogram equalization (HE) is proposed in this paper. We first propose a log-based histogram modification scheme to reduce overstretching artifacts of the conventional HE technique. Then, we develop a power-consumption model for emissive displays and formulate an objective function that consists of the histogram-equalizing term and the power term. By minimizing the objective function based on the convex optimization theory, the proposed algorithm achieves contrast enhancement and power saving simultaneously. Moreover, we extend the proposed algorithm to enhance video sequences, as well as still images. Simulation results demonstrate that the proposed algorithm can reduce power consumption significantly while improving image contrast and perceptual quality.

  6. CW-THz image contrast enhancement using wavelet transform and Retinex

    Science.gov (United States)

    Chen, Lin; Zhang, Min; Hu, Qi-fan; Huang, Ying-Xue; Liang, Hua-Wei

    2015-10-01

    To enhance continuous wave terahertz (CW-THz) scanning images contrast and denoising, a method based on wavelet transform and Retinex theory was proposed. In this paper, the factors affecting the quality of CW-THz images were analysed. Second, an approach of combination of the discrete wavelet transform (DWT) and a designed nonlinear function in wavelet domain for the purpose of contrast enhancing was applied. Then, we combine the Retinex algorithm for further contrast enhancement. To evaluate the effectiveness of the proposed method in qualitative and quantitative, it was compared with the adaptive histogram equalization method, the homomorphic filtering method and the SSR(Single-Scale-Retinex) method. Experimental results demonstrated that the presented algorithm can effectively enhance the contrast of CW-THZ image and obtain better visual effect.

  7. Contrast-enhanced CT and MRI findings of atypical hepatic Echinococcus alveolarisinfestation

    Energy Technology Data Exchange (ETDEWEB)

    Etlik, Oemer; Arslan, Halil; Harman, Mustafa; Temizoez, Osman [Yuzuncu Yil University Faculty of Medicine, Department of Radiology, Van (Turkey); Bay, Ali [Yuzuncu Yil University Faculty of Medicine, Department of Paediatrics, Van (Turkey); Koesem, Mustafa [Yuzuncu Yil University Faculty of Medicine, Department of Pathology, Van (Turkey); Dogan, Ekrem [Yuzuncu Yil University Faculty of Medicine, Department of Internal Medicine, Van (Turkey)

    2005-05-01

    Diagnosis of liver infestation by Echinococcus alveolaris(EA) is based on serological and radiological findings. In this report, we present a 15-year-old girl with atypical hepatic EA infestation showing central punctate calcifications and contrast enhancement on the portal and late phases of CT and MRI. CT showed a hypodense mass involving more than half of the liver with prominent central calcifications. MRI revealed hypointense signal of the infiltrative mass on both T1- and T2-weighted images. Contrast enhancement is a unique finding in hepatic EA infestation that may cause difficulties with diagnosis. MRI may provide invaluable information in the diagnosis of EA infestation of the liver, either by disclosing the infiltrative pattern of infestation without significant effect to vascular structures, or by the signal characteristics. (orig.)

  8. Current consensus and guidelines of contrast enhanced ultrasound for the characterization of focal liver lesions

    Science.gov (United States)

    Jang, Jae Young; Kim, Moon Young; Jeong, Soung Won; Kim, Tae Yeob; Kim, Seung Up; Lee, Sae Hwan; Suk, Ki Tae; Park, Soo Young; Woo, Hyun Young; Kim, Sang Gyune; Heo, Jeong; Baik, Soon Koo; Kim, Hong Soo

    2013-01-01

    The application of ultrasound contrast agents (UCAs) is considered essential when evaluating focal liver lesions (FLLs) using ultrasonography (US). Microbubble UCAs are easy to use and robust; their use poses no risk of nephrotoxicity and requires no ionizing radiation. The unique features of contrast enhanced US (CEUS) are not only noninvasiveness but also real-time assessing of liver perfusion throughout the vascular phases. The later feature has led to dramatic improvement in the diagnostic accuracy of US for detection and characterization of FLLs as well as the guidance to therapeutic procedures and evaluation of response to treatment. This article describes the current consensus and guidelines for the use of UCAs for the FLLs that are commonly encountered in US. After a brief description of the bases of different CEUS techniques, contrast-enhancement patterns of different types of benign and malignant FLLs and other clinical applications are described and discussed on the basis of our experience and the literature data. PMID:23593604

  9. Local ablation therapy with contrast-enhanced ultrasonography for hepatocellular carcinoma: a practical review

    Directory of Open Access Journals (Sweden)

    Tae Kyoung Kim

    2015-10-01

    Full Text Available A successful program for local ablation therapy for hepatocellular carcinoma (HCC requires extensive imaging support for diagnosis and localization of HCC, imaging guidance for the ablation procedures, and post-treatment monitoring. Contrast-enhanced ultrasonography (CEUS has several advantages over computed tomography/magnetic resonance imaging (CT/MRI, including real-time imaging capability, sensitive detection of arterial-phase hypervascularity and washout, no renal excretion, no ionizing radiation, repeatability, excellent patient compliance, and relatively low cost. CEUS is useful for image guidance for isoechoic lesions. While contrast-enhanced CT/MRI is the standard method for the diagnosis of HCC and post-ablation monitoring, CEUS is useful when CT/MRI findings are indeterminate or CT/MRI is contraindicated. This article provides a practical review of the role of CEUS in imaging algorithms for pre- and post-ablation therapy for HCC.

  10. Image contrast enhancement with brightness preservation using an optimal gamma correction and weighted sum approach

    Science.gov (United States)

    Jiang, G.; Wong, C. Y.; Lin, S. C. F.; Rahman, M. A.; Ren, T. R.; Kwok, Ngaiming; Shi, Haiyan; Yu, Ying-Hao; Wu, Tonghai

    2015-04-01

    The enhancement of image contrast and preservation of image brightness are two important but conflicting objectives in image restoration. Previous attempts based on linear histogram equalization had achieved contrast enhancement, but exact preservation of brightness was not accomplished. A new perspective is taken here to provide balanced performance of contrast enhancement and brightness preservation simultaneously by casting the quest of such solution to an optimization problem. Specifically, the non-linear gamma correction method is adopted to enhance the contrast, while a weighted sum approach is employed for brightness preservation. In addition, the efficient golden search algorithm is exploited to determine the required optimal parameters to produce the enhanced images. Experiments are conducted on natural colour images captured under various indoor, outdoor and illumination conditions. Results have shown that the proposed method outperforms currently available methods in contrast to enhancement and brightness preservation.

  11. Local Contrast Enhancement Utilizing Bidirectional Switching Equalization of Separated and Clipped Subhistograms

    Directory of Open Access Journals (Sweden)

    Haidi Ibrahim

    2014-01-01

    Full Text Available Digital image contrast enhancement methods that are based on histogram equalization technique are still useful for the use in consumer electronic products due to their simple implementation. However, almost all the suggested enhancement methods are using global processing technique, which does not emphasize local contents. Therefore, this paper proposes a new local image contrast enhancement method, based on histogram equalization technique, which not only enhances the contrast, but also increases the sharpness of the image. Besides, this method is also able to preserve the mean brightness of the image. In order to limit the noise amplification, this newly proposed method utilizes local mean-separation, and clipped histogram bins methodologies. Based on nine test color images and the benchmark with other three histogram equalization based methods, the proposed technique shows the best overall performance.

  12. Assessment of prostate cancer with dynamic contrast-enhanced computed tomography using an en bloc approach.

    Science.gov (United States)

    Huellner, Martin W; Pauli, Chantal; Mattei, Agostino; Ross, Steffen; Diebold, Joachim; Vosbeck, Jürg; Allgayer, Bernhard; Strobel, Klaus; Veit-Haibach, Patrick

    2014-09-01

    The aim of this study was to assess the performance of dynamic contrast-enhanced computed tomography of the prostate in patients with biopsy-proven prostate cancer. A total of 46 male patients (median age, 65 years; range, 49-73 years) with biopsy-proven prostate cancer underwent an en bloc computed tomography perfusion (CTP) scan of the prostate before surgery. The perfusion parameters mean transit time (MTT), blood flow (BF), and blood volume (BV), as well as the microvessel density (MVD) of surgical specimens were determined. Differences in CTP parameters and MVD among postsurgical Gleason score (sGS) and postsurgical combined Gleason grade (sGG) groups were analyzed. Spearman correlation coefficients were determined between CTP parameters and presurgical biopsy-derived Gleason score (bGS), presurgical biopsy-derived combined Gleason grade (bGG), sGS, sGG, MVD, and pathological tumor stage. A linear regression analysis was carried out for exogenous variables BF, BV, MTT, bGS, and presurgical biopsy-derived combined Gleason grade and endogenous variables sGS, sGG, MVD, and T stage. A receiver operating characteristics analysis was performed to analyze the discriminating performance of CTP parameters and bGS between intermediate- and high-grade tumors. The mean perfusion parameters within the prostate tissue were as follows: BF, 39.1 ± 13.4 mL/100 mL min; BV, 4.9 ± 2.4 mL/100 mL; and MTT, 8.9 ± 3.7 seconds. The mean MVD of the tumor tissue was 144.3 ± 55.6/mm. Computed tomography perfusion parameters and MVD were significantly higher in patients with high-grade tumors compared with those with intermediate-grade tumors (P < 0.01 for BF, BV, and MVD). Only BV and MVD were significantly different among sGS and sGG groups. Moderate correlations were found between BF and sGS (0.38) and between BV and sGS (0.43). Linear relations of BV to sGS and to sGG were found. Blood volume (area under the curve, 0.86) was superior to bGS (area under the curve, 0.75) in

  13. Assessment of esophageal carcinoma undergoing concurrent chemoradiotherapy with quantitative dynamic contrast-enhanced magnetic resonance imaging.

    Science.gov (United States)

    Lei, Jing; Han, Qian; Zhu, Shaocheng; Shi, Dapeng; Dou, Shewei; Su, Zihua; Xu, Xiao

    2015-12-01

    The aim of the present study was to investigate whether quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can predict an early response in primary esophageal carcinoma patients undergoing concurrent chemoradiotherapy. A total of 25 patients with who were pathologically confirmed stage II-III esophageal carcinoma underwent quantitative DCE-MRI prior to chemoradiotherapy, and at 3 weeks post-treatment, the quantitative parameters [K trans (volume transfer constant; the rate at which contrast agent distributes from the plasma to the EES), K ep (rate contrast; the rate at which the contrast agent that has diffused to the EES returns to the plasma) and V e (the contrast agent percentage in the space of the extracellular fluid)] were analyzed respectively. The 25 cases were categorized as a complete response (CR) or a partial response (PR). An independent samples Mann-Whitney U test was used to compare the quantitative parameters between CR and PR. A receiver operating characteristic curve (ROC) was used to determine the best predictor. In total, 17 patients were in the CR group and 8 patients were in the PR group. Pretreatment Ktrans, K ep and V e values were 0.54±0.17/min, 1.12±0.46/min and 0.37±0.14, respectively, in the CR group, and 0.40±0.21/min, 1.07±0.37/min and 0.40±0.22, respectively, in the PR group. There was a significant difference between the two groups for K trans , but there were no significant differences between the two groups for K ep and V e . The K trans , K ep and V e values at 3 weeks post-treatment were 0.33±0.11/min, 0.86±0.31/min and 0.66±0.05, respectively, in the CR group, and 0.62±0.22/min, 1.19±0.39/min and 0.45±0.19, respectively, in the PR group. The corresponding U values were -3.319, -1.719 and -2.628, respectively, and the P-values were 0.006, 0.119 and 0.021, respectively. The areas under the ROC curve of K trans prior to chemoradiotherapy, and of K trans and K ep at 3 weeks post-treatment were 0

  14. Impact of model-based iterative reconstruction on image quality of contrast-enhanced neck CT.

    Science.gov (United States)

    Gaddikeri, S; Andre, J B; Benjert, J; Hippe, D S; Anzai, Y

    2015-02-01

    Improved image quality is clinically desired for contrast-enhanced CT of the neck. We compared 30% adaptive statistical iterative reconstruction and model-based iterative reconstruction algorithms for the assessment of image quality of contrast-enhanced CT of the neck. Neck contrast-enhanced CT data from 64 consecutive patients were reconstructed retrospectively by using 30% adaptive statistical iterative reconstruction and model-based iterative reconstruction. Objective image quality was assessed by comparing SNR, contrast-to-noise ratio, and background noise at levels 1 (mandible) and 2 (superior mediastinum). Two independent blinded readers subjectively graded the image quality on a scale of 1-5, (grade 5 = excellent image quality without artifacts and grade 1 = nondiagnostic image quality with significant artifacts). The percentage of agreement and disagreement between the 2 readers was assessed. Compared with 30% adaptive statistical iterative reconstruction, model-based iterative reconstruction significantly improved the SNR and contrast-to-noise ratio at levels 1 and 2. Model-based iterative reconstruction also decreased background noise at level 1 (P = .016), though there was no difference at level 2 (P = .61). Model-based iterative reconstruction was scored higher than 30% adaptive statistical iterative reconstruction by both reviewers at the nasopharynx (P quality (P model-based iterative reconstruction. Model-based iterative reconstruction offers improved subjective and objective image quality as evidenced by a higher SNR and contrast-to-noise ratio and lower background noise within the same dataset for contrast-enhanced neck CT. Model-based iterative reconstruction has the potential to reduce the radiation dose while maintaining the image quality, with a minor downside being prominent artifacts related to thyroid shield use on model-based iterative reconstruction. © 2015 by American Journal of Neuroradiology.

  15. Gadolinium Contrast Enhancement Improves Confidence in Diagnosing Recurrent Soft Tissue Sarcoma by MRI.

    Science.gov (United States)

    Chou, Shinn-Huey S; Hippe, Daniel S; Lee, Amie Y; Scherer, Kurt; Porrino, Jack A; Davidson, Darin J; Chew, Felix S; Ha, Alice S

    2017-05-01

    To determine how utilization of postgadolinium magnetic resonance imaging (MRI) influenced reader accuracy and confidence at identifying postoperative soft tissue sarcoma (STS) recurrence among readers with various levels of expertise. This retrospective study was institutional review board approved and Health Insurance Portability and Accountability Act compliant. Postoperative MRI from 26 patients with prior STS resection (13 patients with confirmed recurrence, 13 without recurrence) was reviewed. Four blinded readers of varying expertise (radiology resident, fellow, attending, and orthopedic oncologist) initially evaluated only the precontrast images and rated each MRI for recurrence on a 5-point confidence scale. Assessment was repeated with the addition of contrast-enhanced sequences. Diagnostic accuracy based on confidence ratings was evaluated using the area under the receiver operating characteristic curve (AUC). Changes in confidence ratings were calculated using Wilcoxon signed-rank test. All readers demonstrated good diagnostic accuracy both with and without contrast-enhanced images (AUC >0.98 for each reader). When contrast-enhanced images were made available, the resident recorded improved confidence with both assigning (P = 0.031) and excluding recurrence (P = 0.006); the fellow showed improved confidence only with assigning recurrence (P = 0.015); and the surgeon showed improved confidence in excluding recurrence (P = 0.003). The addition of contrast-enhanced images did not significantly influence the diagnostic confidence of the attending radiologist. Diagnostic accuracy of MRI was excellent in evaluating postoperative STS recurrence, and reader confidence improved depending on expertise when postgadolinium imaging was included in the assessment. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  16. Contrast-enhanced MR angiography of abdominal vessels: Is there still a role for angiography?

    Energy Technology Data Exchange (ETDEWEB)

    Vosshenrich, R.; Fischer, U. [Department of Radiology, Georg-August-Universitaet Goettingen (Germany)

    2002-01-01

    The purpose of this review article is to describe recent advantages in contrast-enhanced (CE) three-dimensional (3D) magnetic resonance angiography (MRA) in comparison with other vascular imaging techniques, and to discuss their current clinical applications for the imaging of abdominal vessels. Principles and technical considerations are presented and clinical applications are reviewed for different vascular diseases. In ruptured aortic aneurysms and acute dissections CT is the method of first choice. Contrast-enhanced 3D MRA can be well used for therapeutic planning and follow-up in patients with stable disease. A comprehensive MR examination including CE 3D MRA, MR urography and MR nephrogram has the potential to replace the conventional studies for the evaluation of renal vascular disease. It is an accurate method for imaging the origins of coeliac and superior mesenteric arteries, although the image resolution is too low for reliable assessment of the inferior mesenteric artery. Contrast-enhanced 3D MRA has emerged as the method of choice for studying the portal venous system in liver transplant recipients, in patients with portal hypertension and in cases with abdominal tumours for preoperative evaluation. Additional non-invasive flow measurements are useful in monitoring portal hypertension. The abdominal veins can be well imaged using unenhanced MR techniques. Imaging may be facilitated with intravascular contrast media. Contrast-enhanced 3D MRA can replace intra-arterial DSA for diagnosis, therapy planning and follow-up in patients with abdominal vascular disease. Catheter-based arteriography will still be used for interventional procedures such as percutaneous transluminal angioplasty, stent placement and embolisation. (orig.)

  17. Temporal contrast enhancement and parametric imaging for the visualisation of time patterns in dynamic scintigraphic imaging

    International Nuclear Information System (INIS)

    Deconinck, F.; Bossuyt, A.; Lepoudre, R.

    1982-01-01

    Image contrast, photon noise and sampling frequency limit the visual extraction of relevant temporal information in scintigraphic image series. When the Unitation is mainly due to low temporal contrast, temporal contrast enhancement will strongly improve the perceptibility of time patterns in the series. When the limitation is due to photon noise and limited temporal sampling, parametric imaging by means of the Hadamard transform can visualise temporal patterns. (WU)

  18. Contrast-enhanced MRI of intrasellar arachnoid cysts: relationship between the pituitary gland and cyst

    International Nuclear Information System (INIS)

    Nomura, M.; Kanazawa Univ. School of Medicine; Tachibana, O.; Hasegawa, M.; Kohda, Y.; Nakada, M.; Yamashima, T.; Yamashita, J.; Suzuki, M.

    1996-01-01

    We recently encountered two large intrasellar arachnoid cysts extending to the suprasellar region. The intensity of the cyst contents was identical to that of the cerebrospinal fluid on both T1- and T2-weighted MRI. On contrast-enhanced MRI, the pituitary gland was compressed posteroinferiorly and flattened in the sella turcica. In this report of rare intrasellar arachnoid cysts the discussion is focused on dislocation of the pituitary gland. (orig.)

  19. Three-Dimensional Characterization of Tissue-Engineered Constructs by Contrast-Enhanced Nanofocus Computed Tomography

    OpenAIRE

    Papantoniou, Ioannis; Sonnaert, Maarten; Geris, Liesbet; Luyten, Frank P.; Schrooten, Jan; Kerckhofs, Greet

    2014-01-01

    To successfully implement tissue-engineered (TE) constructs as part of a clinical therapy, it is necessary to develop quality control tools that will ensure accurate and consistent TE construct release specifications. Hence, advanced methods to monitor TE construct properties need to be further developed. In this study, we showed proof of concept for contrast-enhanced nanofocus computed tomography (CE-nano-CT) as a whole-construct imaging technique with a noninvasive potential that enables th...

  20. Leptomeningeal Contrast Enhancement Is Associated with Disability Progression and Grey Matter Atrophy in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Gleb Makshakov

    2017-01-01

    Full Text Available Leptomeningeal contrast enhancement (LMCE on magnetic resonance imaging (MRI is a newly recognized possible biomarker in multiple sclerosis (MS, associated with MS progression and cortical atrophy. In this study, we aimed to assess the prevalence of LMCE foci and their impact on neurodegeneration and disability. Materials. 54 patients with MS were included in the study. LMCE were detected with a 3 Tesla scanner on postcontrast fluid-attenuated inversion-recovery (FLAIR sequence. Expanded Disability Status Scale (EDSS score, number of relapses during 5 years from MS onset, and number of contrast-enhancing lesions on T1 weighted MRI were counted. Results. LMCE was detected in 41% (22/54 of patients. LMCE-positive patients had longer disease duration (p=0,0098 and higher EDSS score (p=0,039, but not a higher relapse rate (p=0,091. No association of LMCE with higher frequency of contrast-enhancing lesions on T1-weighted images was detected (p=0,3842. Analysis of covariates, adjusted for age, sex, and disease duration, revealed a significant effect of LMCE on the cortex volume (p=0.043, F=2.529, the total grey matter volume (p=0.043, F=2.54, and total ventricular volume (p=0.039, F=2.605. Conclusions. LMCE was shown to be an independent and significant biomarker of grey matter atrophy and disability in MS.

  1. Dynamic contrast-enhanced MRI of the prostate. Comparison of two different post-processing algorithms

    International Nuclear Information System (INIS)

    Beyersdorff, Dirk; Franiel, T.; Luedemann, L.; Dietz, E.; Galler, D.; Marchot, P.

    2011-01-01

    Purpose: To evaluate the usefulness of a commercially available post-processing software tool for detecting prostate cancer on dynamic contrast-enhanced magnetic resonance imaging (MRI) and to compare the results to those obtained with a custom-made post-processing algorithm already tested under clinical conditions. Materials and Methods: Forty-eight patients with proven prostate cancer were examined by standard MRI supplemented by dynamic contrast-enhanced dual susceptibility contrast (DCE-DSC) MRI prior to prostatectomy. A custom-made post-processing algorithm was used to analyze the MRI data sets and the results were compared to those obtained using a post-processing algorithm from Invivo Corporation (Dyna CAD for Prostate) applied to dynamic T 1-weighted images. Histology was used as the gold standard. Results: The sensitivity for prostate cancer detection was 78 % for the custom-made algorithm and 60 % for the commercial algorithm and the specificity was 79 % and 82 %, respectively. The accuracy was 79 % for our algorithm and 77.5 % for the commercial software tool. The chi-square test (McNemar-Bowker test) yielded no significant differences between the two tools (p = 0.06). Conclusion: The two investigated post-processing algorithms did not differ in terms of prostate cancer detection. The commercially available software tool allows reliable and fast analysis of dynamic contrast-enhanced MRI for the detection of prostate cancer. (orig.)

  2. Contrast enhancement by arterial perfusion during computed tomography (computed tomographic arteriography) of the pancreatic disease

    International Nuclear Information System (INIS)

    Takaki, Yukiari

    1983-01-01

    Computed tomographic arteriography (CTA) was performed on 52 cases of pancreatic disease in which was suspected clinically, and in which other method failed to yield a definitive diagnosis. For CTA, 65% meglumine diatrizoate 20 ml, diluted 1:3, was injected via a catherter inserted in an artery connected with the pancreas and the change with time of the pacreas CT number was studied. The normal pancreas stains deeply and the best contrast enhancement was obtained between 17 to 21 seconds after instillation of contrast medium. In the CTA findings in pancreatic cancer, low density areas with irregular internal structures are characteristic, and these characteristics were seen even in minute pancreatic cancers which could not be recognized by CT or the intravenous bolus injection method. On the other hand, in chronic pancreatitis, even when differentiation from pancreatic cancer is difficult with arterial and venous encasement in angiography, as long as the chronic pancreatitis is not very advanced ischemic changes are not seen, and this permits differentiation form normal pancreas. This also facilitates differentiation between pancreatitis and pancreatic cancer. In the intravenous bolus injection method, the chronological change of contrast enhancement in the pancreas was studied and the best contrast enhancement was obtained after 60 to 120 seconds. This method revealed no findings peculiar to pancreatic cancer. Based on the above, CTA was found to be useful for making in contributing to establishing a definitive diagnosis, detecting minute pancreatic cancer and to differentiate pancreatic cancer from chronic pancreatitis. (author)

  3. Contrast-enhanced magnetic resonance imaging for the detection of acute haemorrhagic necrotizing pancreatitis

    International Nuclear Information System (INIS)

    Piironen, A.; Kivisaari, R.; Pitkaeranta, P.; Poutanen, V.P.; Laippala, P.; Laurila, P.; Kivisaari, L.

    1997-01-01

    Eleven piglets with haemorrhagic necrotizing pancreatitis and nine piglets with oedematous pancreatitis were imaged using a multi-breath-hold TurboFLASH (TR 6.5 ms, TE 3 ms, TI 300 ms, flip angle 8 , three slices) pre-excited T1-weighted sequence with an IV bolus injection of gadopentetate dimeglumine (Gd-DTPA, 0.3 mmol/kg) as a contrast agent to show dynamic contrast enhancement of the pancreas by MRI. All piglets were imaged according to the same protocol before inducing the disease. Following the IV Gd-DTPA bolus, time-enhancement curve of the pancreas during haemorrhagic necrotizing pancreatitis was significantly lower than during oedematous pancreatitis. The enhancement curves for the healthy piglets and piglets with oedematous pancreatitis did not differ significantly. Each piglet served as its own control. Because the results of this initial study are similar to those obtained with contrast-enhanced CT, we conclude that our results may encourage further clinical trials, and contrast-enhanced dynamic MRI may be an alternative to the established method of CT for diagnosing acute haemorrhagic necrotizing pancreatitis. (orig.). With 3 figs

  4. The conventional and dynamic contrast-enhanced MR imaging findings of lymphoma of the orbit

    International Nuclear Information System (INIS)

    He Liyan; Xian Junfang; Wang Zhenchang; Niu Yantao; Zhao Bo; Zhang Zhengyu

    2007-01-01

    Objective: To evaluate the diagnostic value of conventional and dynamic contrast- enhanced MRI in lymphoma of the orbit. Methods: Thirteen cases of lymphoma of the orbit, including B-C (10 eases), T-C (1 case), T-NK-C (1 case) lymphoma, and multiple myeloma (1 case), were studied using conventional MR and dynamic contrast-enhanced MR imaging with 3D fast spoiled gradient echo sequence. Calculated values included time to peak (Tpeak), washout ratio (WR), slope and enhancement ratio (ER), and time-intensity curves (TICs), and Tpeak, WR, slope and ER were calculated preoperatively. Results: Eleven of the 13 lymphomas of the orbit was seen in the anterior portion of the orbit including eyelid and lacrimal gland. On conventional MRI, 10 cases showed iso-intensity on T 1 WI and T 2 WI and all 13 cases showed moderate enhancement after contrast administration. TIC of all 13 cases showed rapid enhancing and wash-out, Tpeak was (58.7±8.5) s, and WR was (30.9±9.4)%. The accurate diagnosis with only conventional MRI was achieved in 6 out of 13 cases, while the accurate diagnosis was achieved in all 13 cases by using combined conventional MRI and dynamic enhanment MRI. Conclusion: onventional MRI combined with dynamic contrast-enhanced MRI is useful for the diagnosis of lymphoma of the orbit. (authors)

  5. Contrast-enhanced ultrasonography to assess blood perfusion of skeletal muscles in normal dogs

    Science.gov (United States)

    OH, Juyeon; JEON, Sunghoon; CHOI, Jihye

    2015-01-01

    This study evaluated perfusion of skeletal muscle using contrast enhanced ultrasonography in humerus, radius, femur and tibia in normal dogs. Contrast enhanced ultrasonography for each region was performed after injecting 0.5 mL and 1 mL of contrast medium (SonoVue) in every dog. Blood perfusion was assessed quantitatively by measuring the peak intensity, time to the peak intensity and area under the curve from the time–intensity curve. Vascularization in skeletal muscle was qualitatively graded with a score of 0–3 according to the number of vascular signals. A parabolic shape of time–intensity curve was observed from muscles in normal dogs, and time to the peak intensity, the peak intensity and area under the curve of each muscle were not significantly different according to the appendicular regions examined and the dosage of contrast agent administered. This study reports that feasibility of contrast enhanced ultrasonography for assessment of the muscular perfusion in canine appendicular regions. PMID:25754794

  6. The use of contrast-enhanced ultrasound in the characterisation of focal liver lesions

    Science.gov (United States)

    Soye, JA; Mullan, CP; Porter, S; Beattie, H; Barltrop, AH; Nelson, WM

    2007-01-01

    Purpose To determine the potential application of contrast-enhanced ultrasound in the characterisation of focal liver lesions encountered in radiological practice at a district general hospital. Materials & Methods Retrospective analysis of 68 sequential patients undergoing contrast-enhanced ultrasound (CEUS) of liver. All patients were referred for CEUS following identification of 1 or more focal liver lesions on conventional ultrasound or CT imaging. After baseline US examination (Acuson), a bolus of 1.0-2.4 ml of SonoVue (Bracco, UK) was administered intravenously. CEUS images were obtained during arterial, portal venous and delayed phases. Patients were followed up for a mean period of 6 months. The CEUS diagnosis was compared to that indicated by other imaging modalities, histopathology, and clinical follow up. Results CEUS correctly identified malignant liver lesions in 19 patients, with the final diagnosis confirmed by histopathology in 5 cases and clinico-radiological follow up in 14 cases. 47 patients were correctly identified with benign liver lesions on CEUS imaging, with all these cases confirmed on clinico-radiological follow up. In the detection of malignancy, the sensitivity was 95.0% and the specificity was 97.9% Conclusions In our experience to date, contrast-enhanced ultrasound imaging is highly accurate in characterising malignant and benign focal liver lesions. It therefore has significant potential for utilisation in most general radiology departments. PMID:17288301

  7. Software-triggered contrast-enhanced three-dimensional MR angiography of the intracranial arteries.

    Science.gov (United States)

    Isoda, H; Takehara, Y; Isogai, S; Takeda, H; Tanaka, T; Takahashi, M; Nozaki, A; Sun, Y

    2000-02-01

    We investigated the effectiveness of software-triggered contrast-enhanced three-dimensional (3D) MR angiography in evaluating intracranial arteries. We studied 38 patients with suspected brain lesions. Imaging was performed using a 1.5-T superconducting MR system with a commercially available head coil. To monitor signal intensity changes we used software to place a tracker volume at the basilar artery or the internal carotid artery. A 20-ml bolus of gadodiamide hydrate was administered through the antecubital vein at a rate of 2-4 ml/sec, followed by a saline flush. Three-dimensional MR angiography using a spoiled gradient-echo sequence with centric K-space ordering was triggered by the arrival of the contrast bolus in the tracker volume. Imaging times ranged from 12 to 20 sec. We used MR images to assess the effectiveness of contrast-enhanced 3D MR angiography in revealing intracranial arteries with minimal venous overlap. The software triggered imaging on the arrival of the contrast bolus in 81.6% of examinations. In 77.6% of examinations, the resulting MR angiograms revealed intracranial arteries with minimal venous overlap. Software-triggered contrast-enhanced 3D MR angiography with centric K-space ordering is a promising technique for viewing intracranial arteries.

  8. Non-contrast-enhanced peripheral angiography using a sliding interleaved cylinder acquisition.

    Science.gov (United States)

    Kwon, Kie Tae; Kerr, Adam B; Wu, Holden H; Hu, Bob S; Brittain, Jean H; Nishimura, Dwight G

    2015-09-01

    To develop a new sequence for non-contrast-enhanced peripheral angiography using a sliding interleaved cylinder (SLINCYL) acquisition. A venous saturation pulse was incorporated into a three-dimensional magnetization-prepared balanced steady-state free precession sequence for non-contrast-enhanced peripheral angiography to improve artery-vein contrast. The SLINCYL acquisition, which consists of a series of overlapped thin slabs for volumetric coverage similar to the original sliding interleaved ky (SLINKY) acquisition, was used to evenly distribute the venous-suppression effects over the field of view. In addition, the thin-slab-scan nature of SLINCYL and the centric-ordered sampling geometry of its readout trajectory were exploited to implement efficient fluid-suppression and parallel imaging schemes. The sequence was tested in healthy subjects and a patient. Compared to a multiple overlapped thin slab acquisition, both SLINKY and SLINCYL suppressed the venetian blind artifacts and provided similar artery-vein contrast. However, SLINCYL achieved this with shorter scan times and less noticeable artifacts from k-space amplitude modulation than SLINKY. The fluid-suppression and parallel imaging schemes were also validated. A patient study using the SLINCYL-based sequence well identified stenoses at the superficial femoral arteries, which were also confirmed with digital subtraction angiography. Non-contrast-enhanced angiography using SLINCYL can provide angiograms with improved artery-vein contrast in the lower extremities. © 2014 Wiley Periodicals, Inc.

  9. Magnetic resonance angiography of the carotid arteries: comparison of unenhanced and contrast enhanced techniques

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, Harald; Nikolaou, Konstantin; Reiser, Maximilian F. [Ludwig Maximilians University, Department of Clinical Radiology, University Hospitals Munich, Grosshadern Campus, Munich (Germany); Runge, Val M. [University of Texas Medical Branch, Department of Radiology, Galveston, TX (United States); Morelli, John N.; Williams, Kenneth D.; Naul, L.G. [Scott and White Memorial Hospital, Department of Radiology, Temple, TX (United States); Wintersperger, Bernd J. [Ludwig Maximilians University, Department of Clinical Radiology, University Hospitals Munich, Grosshadern Campus, Munich (Germany); University of Toronto, Department of Medical Imaging, UHN, MSH and WCH, Toronto (Canada)

    2011-08-15

    To compare different techniques for carotid imaging including contrast-enhanced, unenhanced and dynamic techniques to find an alternative to contrast-enhanced MRA. 43 patients referred for imaging of the carotids were enrolled in this IRB-approved study. Imaging included dark-blood, time-of-flight, ECG-gated SSFP and dynamic and static contrast-enhanced MRA. Two radiologists evaluated all datasets in terms of image quality (vessel lumen, signal homogeneity, diagnostic confidence, preferred technique) on a four-point Likert-scale and in measuring the vessel area. Of the 43 included patients the first 8 subjects served for protocol optimisation and 4 individuals discontinued the examination. Thus 31 datasets served for evaluation. CE-MRA revealed best results for delineation of vessel lumen, signal homogeneity and diagnostic confidence with values of 3.61, 3.42 and 3.77. It was also rated as the most preferred technique. SSFP-MRA was rated second in all categories with values of 3.1, 2.9 and 3.11. This unenhanced technique was the only one showing non-significantly different results in quantitative analysis. SSFP-MRA, an unenhanced form of MRA, represents an alternative to CE-MRA, particularly in patients where administration of gadolinium for CE-MRA may be contraindicated. In contrast to other techniques, SSFP-MRA serves with not significant different results compared to standard CE-MRA. (orig.)

  10. Quantitative analysis of contrast enhancement of transplanted kidneys under computed tomography

    International Nuclear Information System (INIS)

    Fujita, Tamio; Asano, Haruyoshi; Yanaoka, Masanori; Moriguchi, Ryuichiro; Okishio, Norihiko

    1981-01-01

    Using Hitachi CT-3, the changes in CT numbers of the kidney were calculated in 10 normal and 12 transplanted kidneys. Two mililiters per kg of meglumine diatrizoate (Angiografin) was given intravenously in bolus fashion. Kidneys were scanned before injection, at termination of injection and correctly 10 minutes after injection. In control group, the CT numbers of the cortex, the medulla and the aorta showed rapid increase after contrast administration. Ten minutes after administration of medium, the CT numbers of the medulla remained a little higher than the cortex, though that of the aorta showed rapid decrease. In contrast to control group, in transplanted kidneys the CT numbers of the cortex and medulla showed less increase than the control group just after contrast administration. Moreover, in the recipients who have had good graft function the CT numbers of the cortex and medulla showed gradual increase, in the recipients who have had poor graft function the CT numbers showed gradual decrease 10 minutes after injection. Enhancing indices calculated from the formula: CT numbers 10 minutes after contrast enhancement CT numbers before contrast enhancement were inversely proportional to the serum creatinine. These results lead to the conclusion that the CT scans employing contrast enhancement method after kidney transplantation has the diagnostic value of graft function in addition to diagnostic usefulness for post-transplantation complications such as hematoma, urinoma or lymphocele. (author)

  11. Morphological image processing for quantitative shape analysis of biomedical structures: effective contrast enhancement

    International Nuclear Information System (INIS)

    Kimori, Yoshitaka

    2013-01-01

    A contrast enhancement approach utilizing a new type of mathematical morphology called rotational morphological processing is introduced. The method is quantitatively evaluated and then applied to some medical images. Image processing methods significantly contribute to visualization of images captured by biomedical modalities (such as mammography, X-ray computed tomography, magnetic resonance imaging, and light and electron microscopy). Quantitative interpretation of the deluge of complicated biomedical images, however, poses many research challenges, one of which is to enhance structural features that are scarcely perceptible to the human eye. This study introduces a contrast enhancement approach based on a new type of mathematical morphology called rotational morphological processing. The proposed method is applied to medical images for the enhancement of structural features. The effectiveness of the method is evaluated quantitatively by the contrast improvement ratio (CIR). The CIR of the proposed method is 12.1, versus 4.7 and 0.1 for two conventional contrast enhancement methods, clearly indicating the high contrasting capability of the method

  12. Morphological image processing for quantitative shape analysis of biomedical structures: effective contrast enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Kimori, Yoshitaka, E-mail: kimori@orion.ac.jp [National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787 (Japan)

    2013-11-01

    A contrast enhancement approach utilizing a new type of mathematical morphology called rotational morphological processing is introduced. The method is quantitatively evaluated and then applied to some medical images. Image processing methods significantly contribute to visualization of images captured by biomedical modalities (such as mammography, X-ray computed tomography, magnetic resonance imaging, and light and electron microscopy). Quantitative interpretation of the deluge of complicated biomedical images, however, poses many research challenges, one of which is to enhance structural features that are scarcely perceptible to the human eye. This study introduces a contrast enhancement approach based on a new type of mathematical morphology called rotational morphological processing. The proposed method is applied to medical images for the enhancement of structural features. The effectiveness of the method is evaluated quantitatively by the contrast improvement ratio (CIR). The CIR of the proposed method is 12.1, versus 4.7 and 0.1 for two conventional contrast enhancement methods, clearly indicating the high contrasting capability of the method.

  13. Evaluation of the diagnosis on staging of the bladder cancers by contrast-enhanced ultrasound

    International Nuclear Information System (INIS)

    Gao Yong; Xu Haiyan; Huan Haiming; Chen Yane

    2010-01-01

    Objective: To study the value of the staging of the bladder cancers with the contrast-enhanced ultrasound. Methods: After rapid injection of the contrast agent SonoVue through the elbow vein, the staging of images was completed in 18 cases of bladder cancer. Results: The results of contrast-enhanced ultrasound were compared with post-operative pathological analysis, the rate of accuracy of diagnosis on T1, T2, T3 and T4 stage was 100%, 80%, 83% and 100% respectively. The accuracy made by new methods higher than those of other imaging examinations in T1 stage; the other stages were similar to those of other imaging examinations. Conclusion: The evaluation of Contrast-enhanced ultrasound on the staging of the bladder cancer is higher than that of the conventional ultrasound examination, while the observation of blood flow in the tumor can make accurate diagnosis and differential diagnosis, this method can be complement each other with CT and MRI to improve the rate of accuracy on the staging of bladder cancer. (authors)

  14. Meta-analysis: Serum creatinine changes following contrast enhanced CT imaging

    International Nuclear Information System (INIS)

    Kooiman, Judith; Pasha, Sharif M.; Zondag, Wendy; Sijpkens, Yvo W.J.; Molen, Aart J. van der; Huisman, Menno V.; Dekkers, Olaf M.

    2012-01-01

    Purpose: Contrast induced nephropathy (CIN) is defined as a decrease in renal function following administration of contrast media. The aim of this meta-analysis was to asses the overall risk of CIN, chronic loss of kidney function and the need for renal replacement therapy (RRT) after intravenous contrast enhanced CT-scan. Secondly, we aimed to identify subgroups at increased risk for CIN. Materials and methods: A literature search in Pubmed, Medline, Embase and Cochrane databases was performed. Data extraction was carried out independently by two reviewers. Meta-analysis and meta-regression were performed using an exact likelihood approach. Results: Forty studies evaluating the incidence of CIN after CT were included. The pooled incidence of CIN was 6.4% (95% CI 5.0–8.1). The risk of RRT after CIN was low, 0.06% (95% CI 0.01–0.4). The decline in renal function persisted in 1.1% of patients (95% CI 0.6–2.1%). Patients with chronic kidney disease (odds ratio 2.26, p < 0.001) or diabetes mellitus (odds ratio 3.10, p < 0.001) were at increased risk for the development of CIN. Conclusion: CIN occurred in 6% of patients after contrast enhanced CT. In 1% of all patients undergoing contrast enhanced CT the decline in renal function persisted

  15. Meta-analysis: Serum creatinine changes following contrast enhanced CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kooiman, Judith, E-mail: j.kooiman@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Pasha, Sharif M., E-mail: s.m.pasha@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Zondag, Wendy, E-mail: w.zondag@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Sijpkens, Yvo W.J., E-mail: ysijpens@bronovo.nl [Department of Nephrology, Bronovo Hospital, The Hague (Netherlands); Molen, Aart J. van der, E-mail: molen@lumc.nl [Department of Radiology, LUMC, Leiden (Netherlands); Huisman, Menno V., E-mail: m.v.huisman@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Dekkers, Olaf M., E-mail: o.m.dekkers@lumc.nl [Department of Clinical Epidemiology and Department of Endocrinology, LUMC, Leiden (Netherlands)

    2012-10-15

    Purpose: Contrast induced nephropathy (CIN) is defined as a decrease in renal function following administration of contrast media. The aim of this meta-analysis was to asses the overall risk of CIN, chronic loss of kidney function and the need for renal replacement therapy (RRT) after intravenous contrast enhanced CT-scan. Secondly, we aimed to identify subgroups at increased risk for CIN. Materials and methods: A literature search in Pubmed, Medline, Embase and Cochrane databases was performed. Data extraction was carried out independently by two reviewers. Meta-analysis and meta-regression were performed using an exact likelihood approach. Results: Forty studies evaluating the incidence of CIN after CT were included. The pooled incidence of CIN was 6.4% (95% CI 5.0–8.1). The risk of RRT after CIN was low, 0.06% (95% CI 0.01–0.4). The decline in renal function persisted in 1.1% of patients (95% CI 0.6–2.1%). Patients with chronic kidney disease (odds ratio 2.26, p < 0.001) or diabetes mellitus (odds ratio 3.10, p < 0.001) were at increased risk for the development of CIN. Conclusion: CIN occurred in 6% of patients after contrast enhanced CT. In 1% of all patients undergoing contrast enhanced CT the decline in renal function persisted.

  16. Contrast-enhanced ultrsonography advanced and currrent status in abdominal imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chung Yong Eun; Kim Ki Whang [Dept. of Radiology, Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2015-01-15

    n the field of contrast-enhanced ultrasonography (US), contrast agents are classified as either first- or second-generation agents depending on the gas within the microbubbles. In the case of first-generation contrast agents, a high-mechanical-index technique is used and only intermittent scanning is possible due to the early destruction of the microbubbles during the scanning. The use of second-generation contrast agents in a low-mechanical-index technique enables continuous scanning. Besides the detection and characterization of focal liver lesions, contrastenhanced US is helpful in the monitoring of radiofrequency ablation therapy and in the targeting step of an US-guided biopsy. Recently, there has been a demand for new criteria to evaluate the treatment response obtained using anti-angiogenic agents because morphologic criteria alone may not reflect the treatment response of the tumor and contrast-enhanced US can provide quantitative markers of tissue perfusion. In spite of the concerns related to its cost-effectiveness, contrast-enhanced US has the potential to be more widely used as a complimentary tool or to substitute the current imaging modalities in some occasions.

  17. A preliminary evaluation of self-made nanobubble in contrast-enhanced ultrasound imaging

    Science.gov (United States)

    Li, Chunfang; Wu, Kaizhi; Li, Jing; Liu, Haijuan; Zhou, Qibing; Ding, Mingyue

    2014-03-01

    Nanoscale bubbles (nanobubbles) have been reported to improve contrast in tumor-targeted ultrasound imaging due to the enhanced permeation and retention effects at tumor vascular leaks. In this work, a self-made nanobubble ultrasound contrast agent was preliminarily characterized and evaluated in-vitro and in-vivo. Fundamental properties such as morphology appearance, size distribution, zeta potential, bubble concentration (bubble numbers per milliliter contrast agent suspension) and the stability of nanobubbles were assessed by light microscope and particle sizing analysis. Then the concentration intensity curve and time intensity curves (TICs) were acquired by ultrasound imaging experiment in-vitro. Finally, the contrast-enhanced ultrasonography was performed on rat to investigate the procedure of liver perfusion. The results showed that the nanobubbles had good shape and uniform distribution with the average diameter of 507.9 nm, polydispersity index (PDI) of 0.527, and zeta potential of -19.17 mV. Significant contrast enhancement was observed in in-vitro ultrasound imaging, demonstrating that the self-made nanobubbles can enhance the contrast effect of ultrasound imaging efficiently in-vitro. Slightly contrast enhancement was observed in in-vivo ultrasound imaging, indicating that the nanobubbles are not stable enough in-vivo. Future work will be focused on improving the ultrasonic imaging performance, stability, and antibody binding of the nanoscale ultrasound contrast agent.

  18. Differentiation between tuberculosis and lymphoma in mediastinal lymph nodes: Evaluation with contrast-enhanced MDCT

    International Nuclear Information System (INIS)

    Tang, S.-S.; Yang, Z.-G.; Deng, W.; Shao, H.; Chen, J.; Wen, L.-Y.

    2012-01-01

    Aim: To determine the specific imaging criteria on contrast-enhanced multidetector computed tomography (MDCT) for differentiating between tuberculosis and lymphoma in mediastinal lymph nodes. Materials and methods: The anatomical distribution and enhancement patterns of mediastinal lymph nodes on contrast-enhanced MDCT were reviewed in 37 patients with tuberculosis and 54 patients with lymphoma. Of the patients with lymphoma, 18 had Hodgkin's disease and 36 had non-Hodgkin's lymphoma. Results: Region 10R was involved more often in tuberculosis than in Hodgkin's disease and non-Hodgkin's lymphoma. Region 6 had a higher tendency to be affected in Hodgkin's disease and non-Hodgkin's lymphoma compared with tuberculosis. Tuberculosis showed peripheral enhancement in 78% of cases, frequently with a multilocular appearance, compared to Hodgkin's disease and non-Hodgkin's lymphoma, which showed peripheral enhancement in only 6 and 3% of cases, respectively. Homogeneous enhancement was more commonly seen in lymphoma (83% for Hodgkin's disease, and 83% for non-Hodgkin's lymphoma) than in tuberculosis (8%). In the determination of tuberculosis, results showed that when a peripheral enhancement pattern was seen, sensitivity was 78%, specificity was 96%, and accuracy was 89%. In the determination of lymphoma, results showed that when a homogeneous enhancement pattern was seen, sensitivity was 83%, specificity was 92%, and accuracy was 87%. Conclusion: The findings of the present study indicate that specific anatomical distribution and enhancement patterns of lymphadenopathy shown on contrast-enhanced MDCT can be useful in differentiating tuberculosis from lymphoma of mediastinal lymph nodes.

  19. Tracer kinetic model-driven registration for dynamic contrast-enhanced MRI time-series data.

    Science.gov (United States)

    Buonaccorsi, Giovanni A; O'Connor, James P B; Caunce, Angela; Roberts, Caleb; Cheung, Sue; Watson, Yvonne; Davies, Karen; Hope, Lynn; Jackson, Alan; Jayson, Gordon C; Parker, Geoffrey J M

    2007-11-01

    Dynamic contrast-enhanced MRI (DCE-MRI) time series data are subject to unavoidable physiological motion during acquisition (e.g., due to breathing) and this motion causes significant errors when fitting tracer kinetic models to the data, particularly with voxel-by-voxel fitting approaches. Motion correction is problematic, as contrast enhancement introduces new features into postcontrast images and conventional registration similarity measures cannot fully account for the increased image information content. A methodology is presented for tracer kinetic model-driven registration that addresses these problems by explicitly including a model of contrast enhancement in the registration process. The iterative registration procedure is focused on a tumor volume of interest (VOI), employing a three-dimensional (3D) translational transformation that follows only tumor motion. The implementation accurately removes motion corruption in a DCE-MRI software phantom and it is able to reduce model fitting errors and improve localization in 3D parameter maps in patient data sets that were selected for significant motion problems. Sufficient improvement was observed in the modeling results to salvage clinical trial DCE-MRI data sets that would otherwise have to be rejected due to motion corruption. Copyright 2007 Wiley-Liss, Inc.

  20. Age-related contrast enhancement study of normal bone marrow in lumbar spinal MR imaging

    International Nuclear Information System (INIS)

    Kim, Young A; Ha, Doo Hoe

    1999-01-01

    The purpose of this study was to evaluate the degree of contrast enhancement of normal bone marrow in L-spine relating to aging and to determine the range of contrast enhancement in normal bone marrow. We analyzed a total of 120 patients (20 per decade) who had undergone lumbar spinal MRI and who ranged in age from the 2nd decade to more than the 7th. Bone marrow revealed no abnormal pathology. Sagittal T1-weighted spin echo sequences were obtained before and after gadolinium administration. For each sequence, a region of interest was drawn within the L1 vertebral body from the midsagittal slice. Signal intensity (SI) values of each sequence were ascertained and the percentage increase in SI was calculated. After contrast enhancement, lumbar MRI revealed no statistically significant in the percentage increase in SI of normal bone marrow in relation to aging. Most patients (99%) however showed an SI increase of between 10% and 49%. In only four, none of whom were aged over 40, was this increase above 50%. Lumbar MRI, revealed no statistically significant difference in percentage increase in SI in normal bone marrow relating to aging, but when the increase is above 50% in a patient aged over 40, bone marrow pathology should be further investigated

  1. High-relaxivity contrast-enhanced magnetic resonance neuroimaging: a review

    Energy Technology Data Exchange (ETDEWEB)

    Giesel, Frederik L. [German Cancer Research Centre (DKFZ), Department of Radiology E010, Heidelberg (Germany); University of Heidelberg, Nuclear Medicine, Heidelberg (Germany); Mehndiratta, Amit [German Cancer Research Centre (DKFZ), Department of Radiology E010, Heidelberg (Germany); Harvard Medical School, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Essig, Marco [German Cancer Research Centre (DKFZ), Department of Radiology E010, Heidelberg (Germany)

    2010-10-15

    Evaluation of brain lesions using magnetic resonance imaging (MRI) provides information that is critical for accurate diagnosis, prognosis, therapeutic intervention and monitoring response. Conventional contrast-enhanced MR neuroimaging using gadolinium (Gd) contrast agents primarily depicts disruption of the blood-brain barrier, demonstrating location and extent of disease, and also the morphological details at the lesion site. However, conventional imaging results do not always accurately predict tumour aggressiveness. Advanced functional MRI techniques such as dynamic contrast-enhanced perfusion-weighted imaging utilise contrast agents to convey physiological information regarding the haemodynamics and neoangiogenic status of the lesion that is often complementary to anatomical information obtained through conventional imaging. Most of the Gd contrast agents available have similar T1 and T2 relaxivities, and thus their contrast-enhancing capabilities are comparable. Exceptions are gadobenate-dimeglumine, Gd-EOB-DTPA, Gadobutrol and gadofosveset, which, owing to their transient-protein-binding capability, possess almost twice (and more) the T1 and T2 relaxivities as other agents at all magnetic field strengths. Numerous comparative studies have demonstrated the advantages of the increased relaxivity in terms of enhanced image contrast, image quality and diagnostic confidence. Here we summarise the benefits of higher relaxivity for the most common neuroimaging applications including MRI, perfusion-weighted imaging and MRA for evaluation of brain tumours, cerebrovascular disease and other CNS lesions. (orig.)

  2. CT colonography: Diagnostic role of contrast enhancement of benign polyps and colorectal carcinoma

    International Nuclear Information System (INIS)

    Stoinova, V.; Nedevska, M.

    2006-01-01

    Full text: The aim of this study was to compare pre- and postcontrast CT attenuation values of benign colorectal polyps and carcinoma lesions detected by CT colonography, and to investigate whether contrast enhancement of these lesions can be potentially used for differentiation from residual fluid and feces. We retrospectively reviewed CT colonographic dataset of 120 patients. 35 benign polyps and 22 colorectal carcinomas were included in our study. All lesions were confirmed by colonoscopic biopsy or surgery. The difference in attenuation value between precontrast and postcontrast studies of polyps was statistically significant; the same was true for colorectal cancers. In the precontrast phase no statistically significant difference was observed between stool, polyps and cancers. The mean attenuation value of solid fecal residuals was 37 HU before and after contrast enhancement. Residual fluid do not take up contrast and the density does not change in the contrast-enhanced phase. The difference between postcontrast density of polyps and cancers with respect to density of stools and residual fluid was significant. The use of contrast medium could be helpful in CT colonography for discriminating polypoid benign lesions and colorectal cancer from fecal and fluid residuals

  3. [Contrast enhanced ultrasound can show symptomatic carotid lesions not visualized with magnetic resonance angiography].

    Science.gov (United States)

    Baud, J-M; Becker, F; Maurizot, A; Pico, F

    2013-12-01

    We report the cases of two patients who presented symptoms focused on a wall of the common carotid: carotidodynia in one patient and a transient ischemic attack in the other. The B-mode ultrasound showed an enlarged thickened medio-adventitial echostructure with a slightly heterogeneous and iso or hypoechoic appearance. There was no narrowing. Injection of ultrasound contrast led to significant enhancement in the wall reflecting neovascularization secondary to inflammation. Other imaging methods (MR and CT angiography) found no abnormality. At the 3-month follow-up visit, the surface area of the lesions was greatly decreased and the ultrasound contrast enhancement had disappeared. These two cases illustrate how focal lesions of the carotid wall missed on MR and CT angiography can be detected and visualized with B-mode ultrasound contrast enhancement. Contrast enhanced ultrasound leads to the concept of "active lesions" resulting from inflammatory processes that can be readily monitored without radiation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  4. Predicting IDH mutation status of intrahepatic cholangiocarcinomas based on contrast-enhanced CT features

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yong [Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Department of Radiology, Nanjing, Jiangsu Province (China); Chen, Jun [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Pathology, Nanjing, Jiangsu Province (China); Kong, Weiwei [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Oncology, Nanjing, Jiangsu Province (China); Mao, Liang; Qiu, Yudong [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Hepatopancreatobiliary Surgery, Nanjing, Jiangsu Province (China); Kong, Wentao [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Ultrasonography, Nanjing, Jiangsu Province (China); Zhou, Qun [Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Department of Radiology, Nanjing, Jiangsu Province (China); Zhou, Zhengyang; Zhu, Bin; He, Jian [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Radiology, Nanjing, Jiangsu Province (China); Wang, Zhongqiu [Jiangsu Province Hospital of Traditional Chinese Medicine, the Affiliated Hospital of Nanjing University of Chinese Medicine, Department of Radiology, Nanjing, Jiangsu Province (China)

    2018-01-15

    To explore the difference in contrast-enhanced computed tomography (CT) features of intrahepatic cholangiocarcinomas (ICCs) with different isocitrate dehydrogenase (IDH) mutation status. Clinicopathological and contrast-enhanced CT features of 78 patients with 78 ICCs were retrospectively analysed and compared based on IDH mutation status. There were 11 ICCs with IDH mutation (11/78, 14.1%) and 67 ICCs without IDH mutation (67/78, 85.9%). IDH-mutated ICCs showed intratumoral artery more often than IDH-wild ICCs (p = 0.023). Most ICCs with IDH mutation showed rim and internal enhancement (10/11, 90.9%), while ICCs without IDH mutation often appeared diffuse (26/67, 38.8%) or with no enhancement (4/67, 6.0%) in the arterial phase (p = 0.009). IDH-mutated ICCs showed significantly higher CT values, enhancement degrees and enhancement ratios in arterial and portal venous phases than IDH-wild ICCs (all p < 0.05). The CT value of tumours in the portal venous phase performed best in distinguishing ICCs with and without IDH mutation, with an area under the curve of 0.798 (p = 0.002). ICCs with and without IDH mutation differed significantly in arterial enhancement mode, and the tumour enhancement degree on multiphase contrast-enhanced CT was helpful in predicting IDH mutation status. (orig.)

  5. Calcifications of the thoracic aorta on extended non-contrast-enhanced cardiac CT.

    Directory of Open Access Journals (Sweden)

    Damian Craiem

    Full Text Available BACKGROUND: The presence of calcified atherosclerosis in different vascular beds has been associated with a higher risk of mortality. Thoracic aorta calcium (TAC can be assessed from computed tomography (CT scans, originally aimed at coronary artery calcium (CAC assessment. CAC screening improves cardiovascular risk prediction, beyond standard risk assessment, whereas TAC performance remains controversial. However, the curvilinear portion of the thoracic aorta (TA, that includes the aortic arch, is systematically excluded from TAC analysis. We investigated the prevalence and spatial distribution of TAC all along the TA, to see how those segments that remain invisible in standard TA evaluation were affected. METHODS AND RESULTS: A total of 970 patients (77% men underwent extended non-contrast cardiac CT scans including the aortic arch. An automated algorithm was designed to extract the vessel centerline and to estimate the vessel diameter in perpendicular planes. Then, calcifications were quantified using the Agatston score and associated with the corresponding thoracic aorta segment. The aortic arch and the proximal descending aorta, "invisible" in routine CAC screening, appeared as two vulnerable sites concentrating 60% of almost 11000 calcifications. The aortic arch was the most affected segment per cm length. Using the extended measurement method, TAC prevalence doubled from 31% to 64%, meaning that 52% of patients would escape detection with a standard scan. In a stratified analysis for CAC and/or TAC assessment, 111 subjects (46% women were exclusively identified with the enlarged scan. CONCLUSIONS: Calcium screening in the TA revealed that the aortic arch and the proximal descending aorta, hidden in standard TA evaluations, concentrated most of the calcifications. Middle-aged women were more prone to have calcifications in those hidden portions and became candidates for reclassification.

  6. Dynamic contrast-enhanced MRI in breast cancer treated with neoadjuvant chemotherapy: correlation with pathological response

    International Nuclear Information System (INIS)

    Li Jie; Zhang Xiaopeng; Lu Aiping; Ouyang Tao; Cao Kun; Sun Yingshi; Tang Lei

    2007-01-01

    Objective: To investigate the relationship of pathological response of breast cancer after neoadjuvant chemotherapy with the imaging findings in dynamic contrast-enhanced MRI. Methods: Forty- five patients with pathologically confirmed breast carcinoma who finished courses of neoadjuvant chemotherapy had breast MRI prior to operation. Dynamic contrast-enhanced MRI scans were performed on a 1.5 T scanner using 3D SPGR sequence before and repeated 6 times after administration of Gd-DTPA. Pathological response was assessed by a pathologist according to Miller and Payne five points classification blinded to breast MRI results. Grade 5 was defined as pCR (pathological complete response). Grade 4 and 5 were defined as major histopathological response (MHR). The type of time signal intensity curve (TIC) (three types), pattern of residual enhancement of each breast cancer were recorded and correlated with pathological findings. Fisher exact test was used for statistical analysis. Results: Grade 5 responses were achieved in seven patients; grade 4 in sixteen patients; grade 3 in sixteen patients and grade 1-2 in six patients. 70.0% (14/20) of type I time signal intensity curve correlated with MHR, while all 6 type III curves showed non-MHR response. The type of time signal intensity curve and pathological response grades had statistically significant correlation (P=0.001). 18 of the 23 cases with MHR exhibited residual enhancement,while the remaining 5 cases showed no enhancement. Of the 18 MHR cases with residual enhancement, 11 showed non-mass-like enhancement and 7 showed mass-like enhancement. The mass (non-mass) morphological pattern in dynamic contrast enhanced-MRI had statistically significant differences in pathological response (P=0.012). Conclusions Pathological response of breast carcinoma after neoadjuvant chemotherapy could be characterized using dynamic contrast-enhanced MRI by identifying patterns of residual contrast enhancement and kinetic curve. Favorable

  7. Multipurpose contrast enhancement on epiphyseal plates and ossification centers for bone age assessment.

    Science.gov (United States)

    Chai, Hum Yan; Swee, Tan Tian; Seng, Gan Hong; Wee, Lai Khin

    2013-04-08

    The high variations of background luminance, low contrast and excessively enhanced contrast of hand bone radiograph often impede the bone age assessment rating system in evaluating the degree of epiphyseal plates and ossification centers development. The Global Histogram equalization (GHE) has been the most frequently adopted image contrast enhancement technique but the performance is not satisfying. A brightness and detail preserving histogram equalization method with good contrast enhancement effect has been a goal of much recent research in histogram equalization. Nevertheless, producing a well-balanced histogram equalized radiograph in terms of its brightness preservation, detail preservation and contrast enhancement is deemed to be a daunting task. In this paper, we propose a novel framework of histogram equalization with the aim of taking several desirable properties into account, namely the Multipurpose Beta Optimized Bi-Histogram Equalization (MBOBHE). This method performs the histogram optimization separately in both sub-histograms after the segmentation of histogram using an optimized separating point determined based on the regularization function constituted by three components. The result is then assessed by the qualitative and quantitative analysis to evaluate the essential aspects of histogram equalized image using a total of 160 hand radiographs that are implemented in testing and analyses which are acquired from hand bone online database. From the qualitative analysis, we found that basic bi-histogram equalizations are not capable of displaying the small features in image due to incorrect selection of separating point by focusing on only certain metric without considering the contrast enhancement and detail preservation. From the quantitative analysis, we found that MBOBHE correlates well with human visual perception, and this improvement shortens the evaluation time taken by inspector in assessing the bone age. The proposed MBOBHE outperforms

  8. Temporomandibular joint (TMJ) pain revisited with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)

    International Nuclear Information System (INIS)

    Tasali, N.; Cubuk, R.; Aricak, M.; Ozarar, M.; Saydam, B.; Nur, H.; Tuncbilek, N.

    2012-01-01

    Purpose: We aimed to assess the contrast enhancement patterns of the retrodiscal tissue with dynamic contrast-enhanced MR imaging (DCE-MRI) with respect to different temporomandibular joint disc pathologies. Additionally, we questioned the relationship between the temporomandibular joint (TMJ) pain and the contrast enhancement pattern of the retrodiscal tissue regardless of the TMJ disc position. Materials and methods: 52 joints of 26 patients (4 males and 22 females) who have pain in at least at one of their TMJ were included in this study. For the qualitative analysis, the joints were divided into four groups in terms of their disc positions: normal (1), partially displaced with or without reduction (2), totally dislocated with reduction (3) and totally dislocated without reduction (4). Besides, two different joint groups were constituted, namely the painful group and painless group according to the clinical findings without taking the TMJ disc positions into account. Quantitative analyses were made by means of measuring signal intensity ratios (SI) ratio at the retrodiscal tissue (from internal side and external side of the each joint) using DCE-MRI and these measurements were analyzed with paired samples t test to define the difference between the measurements. At the second stage, the time-dependent arithmetical mean values of the SI ratios were calculated for each joint group and significant differences between the groups were questioned using analysis of variance (ANOVA) test. Besides, painful and painless groups which were classified on the basis of the clinical data were compared according to the mean SI ratios found for each joint and the significant differences between these two groups were assessed by means of Student's T test. The results were assessed in 95% confidence interval where the significance level was p < 0.05. Results: A significant difference was observed between the internal and external contrast enhancement of the joints with partial

  9. Dynamic contrast enhanced-MRI for the detection of pathological complete response to neoadjuvant chemotherapy for locally advanced rectal cancer

    International Nuclear Information System (INIS)

    Gollub, M.J.; Gultekin, D.H.; Akin, O.; Do, R.K.; Fuqua, J.L.; Gonen, M.; Kuk, D.; Weiser, M.; Paty, P.; Guillem, J.; Nash, G.M.; Temple, L.; Saltz, L.; Schrag, D.; Goodman, K.; Shia, J.; Schwartz, L.H.

    2012-01-01

    To determine the ability of dynamic contrast enhanced (DCE-MRI) to predict pathological complete response (pCR) after preoperative chemotherapy for rectal cancer. In a prospective clinical trial, 23/34 enrolled patients underwent pre- and post-treatment DCE-MRI performed at 1.5T. Gadolinium 0.1 mmol/kg was injected at a rate of 2 mL/s. Using a two-compartmental model of vascular space and extravascular extracellular space, K trans , k ep , v e , AUC90, and AUC180 were calculated. Surgical specimens were the gold standard. Baseline, post-treatment and changes in these quantities were compared with clinico-pathological outcomes. For quantitative variable comparison, Spearman's Rank correlation was used. For categorical variable comparison, the Kruskal-Wallis test was used. P ≤ 0.05 was considered significant. Percentage of histological tumour response ranged from 10 to 100%. Six patients showed pCR. Post chemotherapy K trans (mean 0.5 min -1 vs. 0.2 min -1 , P = 0.04) differed significantly between non-pCR and pCR outcomes, respectively and also correlated with percent tumour response and pathological size. Post-treatment residual abnormal soft tissue noted in some cases of pCR prevented an MR impression of complete response based on morphology alone. After neoadjuvant chemotherapy in rectal cancer, MR perfusional characteristics have been identified that can aid in the distinction between incomplete response and pCR. (orig.)

  10. Radiofrequency ablation of renal tumours: diagnostic accuracy of contrast-enhanced ultrasound for early detection of residual tumour

    Energy Technology Data Exchange (ETDEWEB)

    Hoeffel, Christine [Service de Radiologie, CHU de Reims, Hopital Robert Debre, Pole d' imagerie, Reims Cedex (France); Pousset, Maud; Elie, Caroline [Universite Paris-Descartes, AP-HP, Departement de Biostatistiques, Hopital Necker, Paris Cedex 15 (France); Timsit, Marc-Olivier; Mejean, Arnaud [Universite Paris-Descartes, AP-HP, Service d' urologie, Hopital Necker, Paris Cedex 15 (France); Merran, Samuel [Federation mutualiste parisienne, Service d' imagerie medicale, Paris (France); Tranquart, Francois [Bracco Research, Plan les Ouates (Switzerland); Khairoune, Ahmed; Helenon, Olivier; Correas, Jean-Michel [Universite Paris-Descartes, AP-HP, Service de Radiologie Adultes, Hopital Necker, Paris Cedex 15 (France); Joly, Dominique [Universite Paris-Descartes, AP-HP, Service de Nephrologie, Hopital Necker, Paris Cedex 15 (France); Richard, Stephane [Service d' urologie, Hopital de Bicetre, Centre Pilote Tumeurs rares INCa, AP-HP, Le Kremlin-Bicetre (France); Hopital Necker, Service de Nephrologie, Paris Cedex 15 (France); Le Kremlin-Bicetre et Institut de Cancerologie Gustave Roussy, Genetique oncologique, CNRS FRE 2939, Faculte de medecine Paris-Sud, Villejuif (France)

    2010-08-15

    To evaluate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) in the early detection of residual tumour after radiofrequency ablation (RFA) of renal tumours. Patients referred to our institution for RFA of renal tumours prospectively underwent CEUS and computed tomography (CT) or magnetic resonance imaging (MRI) before, within 1 day and 6 weeks after treatment. Identification of residual tumour was assessed by three blinded radiologists. Reference standard was CT/MRI performed at least 1 year after RFA. A total of 66 renal tumours in 43 patients (median age 62 years; range 44-71.5) were studied. Inter-reader agreement ({kappa} value) was 0.84 for CEUS. Prevalence of residual disease was 19%. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), respectively, were as follows: 64% [confidence interval (CI) 39-84], 98% [CI 91-100], 82% [CI 52-95] and 92% [CI 83-97] on 24-h CEUS; 79% [CI 52-92], 100% [CI 94-100], 100% [CI 74-100] and 95% [CI 87-100] on 6-week CEUS; 79% [CI 52-92], 95% [CI 86-98], 79% [CI 52-92] and 95% [CI 86-98] on 24-h CT/MRI; and 100% [CI 72-100], 98% [CI 90-100], 91% [CI 62-98] and 100% [CI 93-100] on 6-week CT/MRI. CEUS has high specificity for the early diagnosis of residual tumour after renal RFA. (orig.)

  11. Contrast-enhanced spectral mammography versus MRI: Initial results in the detection of breast cancer and assessment of tumour size

    Energy Technology Data Exchange (ETDEWEB)

    Fallenberg, E.M.; Renz, D.M. [Charite - Universitaetsmedizin Berlin, Clinic of Radiology, Berlin (Germany); Dromain, C. [Institut Gustave Roussy, Department of Radiology, Villejuif cedex (France); Diekmann, F. [St. Joseph-Stift Bremen, Department of Medical Imaging, Bremen (Germany); Engelken, F.; Krohn, M.; Singh, J.M.; Bick, U. [Charite - Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany); Ingold-Heppner, B. [Charite - Universitaetsmedizin Berlin, Institute of Pathology, Berlin (Germany); Winzer, K.J. [Charite - Universitaetsmedizin Berlin, Breast Center, Department of Gynecology, Berlin (Germany)

    2014-01-15

    To compare mammography (MG), contrast-enhanced spectral mammography (CESM), and magnetic resonance imaging (MRI) in the detection and size estimation of histologically proven breast cancers using postoperative histology as the gold standard. After ethical approval, 80 women with newly diagnosed breast cancer underwent MG, CESM, and MRI examinations. CESM was reviewed by an independent experienced radiologist, and the maximum dimension of suspicious lesions was measured. For MG and MRI, routine clinical reports of breast specialists, with judgment based on the BI-RADS lexicon, were used. Results of each imaging technique were correlated to define the index cancer. Fifty-nine cases could be compared to postoperative histology for size estimation. Breast cancer was visible in 66/80 MG, 80/80 CESM, and 77/79 MRI examinations. Average lesion largest dimension was 27.31 mm (SD 22.18) in MG, 31.62 mm (SD 24.41) in CESM, and 27.72 mm (SD 21.51) in MRI versus 32.51 mm (SD 29.03) in postoperative histology. No significant difference was found between lesion size measurement on MRI and CESM compared with histopathology. Our initial results show a better sensitivity of CESM and MRI in breast cancer detection than MG and a good correlation with postoperative histology in size assessment. (orig.)

  12. Dynamic contrast-enhanced MRI for treatment response assessment in patients with oesophageal cancer receiving neoadjuvant chemoradiotherapy.

    Science.gov (United States)

    Heethuis, Sophie E; van Rossum, Peter S N; Lips, Irene M; Goense, Lucas; Voncken, Francine E; Reerink, Onne; van Hillegersberg, Richard; Ruurda, Jelle P; Philippens, Marielle E; van Vulpen, Marco; Meijer, Gert J; Lagendijk, Jan J W; van Lier, Astrid L H M W

    2016-07-01

    To explore and evaluate the potential value of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) for the prediction of pathologic response to neoadjuvant chemoradiotherapy (nCRT) in oesophageal cancer. Twenty-six patients underwent DCE-MRI before, during (week 2-3) and after nCRT, but before surgery (pre/per/post, respectively). Histopathologic tumour regression grade (TRG) was assessed after oesophagectomy. Tumour area-under-the-concentration time curve (AUC), time-to-peak (TTP) and slope were calculated. The ability of these DCE-parameters to distinguish good responders (GR, TRG 1-2) from poor responders (noGR, TRG⩾3), and pathologic complete responders (pCR) from no-pCR was assessed. Twelve patients (48%) showed GR of which 8 patients (32%) pCR. Analysis of AUC change throughout treatment, AUCper-pre, was most predictive for GR, at a threshold of 22.7% resulting in a sensitivity of 92%, specificity of 77%, PPV of 79%, and a NPV of 91%. AUCpost-pre was most predictive for pCR, at a threshold of -24.6% resulting in a sensitivity of 83%, specificity of 88%, PPV of 71%, and a NPV of 93%. TTP and slope were not associated with pathologic response. This study demonstrates that changes in AUC throughout treatment are promising for prediction of histopathologic response to nCRT for oesophageal cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Contrast-enhanced ultrasonography with intraarterial administration of SonoVue for guidance of transarterial chemoembolization: an initial experience.

    Science.gov (United States)

    Moschouris, Hippocrates; Malagari, Katerina; Kalokairinou, Marianna; Stamatiou, Konstantinos; Marinis, Athanasios; Papadaki, Marina Georgiou

    2011-12-01

    To describe the technique and to evaluate the feasibility of contrast-enhanced ultrasound with intraarterial administration of echo-enhancer (i.a CEUS) as a method for guidance of transarterial chemoembolization (TACE). Twelve patients with 17 target liver tumors underwent superselective TACE, guided with i.a CEUS. After microcatheter placement in a (sub)segmental artery suspected as a tumor feeder, a diluted suspension of SonoVue was injected through the microcatheter, and imaging of the target tumor was performed with a low mechanical index technique and with contrast-specific software. If intraarterial injection of SonoVue was associated with immediate, strong tumoral enhancement, the injected artery was considered as tumor-feeding and TACE was performed, otherwise another artery was evaluated. From 25 segmental or subsegmental arteries evaluated i.a CEUS confirmed that 16 arteries were actually tumor feeders and unequivocal excluding 4 arteries as a tumor arterial supply. The remainder 5 arterial branches could not be safely characterized due to artifacts or technical limitations. In 8 patients in which tumoral vascular supply could not be elucidated by angiography alone, i.a CEUS increased the accuracy of supereselective embolization, and provided other clinically relevant information in 2 of these patients. No adverse effects were observed. For guidance of superselective TACE i.a CEUS is a safe and feasible method..

  14. Treatment response evaluation with three-dimensional contrast-enhanced ultrasound for liver cancer after local therapies

    Energy Technology Data Exchange (ETDEWEB)

    Xu Huixiong, E-mail: xuhuixiong@hotmail.co [Department of Medical Ultrasonics, Institute of Diagnostic and Interventional Ultrasound, First Affiliated Hospital, Sun Yat-Sen University, 58th Zhongshan Road 2, Guangzhou 510080 (China); Lu Mingde, E-mail: lumd@21cn.co [Department of Hepatobiliary Surgery, First Affiliated Hospital, Sun Yat-Sen University, 58th Zhongshan Road 2, Guangzhou 510080 (China); Xie Xiaohua; Xie Xiaoyan [Department of Medical Ultrasonics, Institute of Diagnostic and Interventional Ultrasound, First Affiliated Hospital, Sun Yat-Sen University, 58th Zhongshan Road 2, Guangzhou 510080 (China); Kuang Ming [Department of Hepatobiliary Surgery, First Affiliated Hospital, Sun Yat-Sen University, 58th Zhongshan Road 2, Guangzhou 510080 (China); Xu Zuofeng; Liu Guangjian; Wang Zhu; Chen Lida; Lin Manxia [Department of Medical Ultrasonics, Institute of Diagnostic and Interventional Ultrasound, First Affiliated Hospital, Sun Yat-Sen University, 58th Zhongshan Road 2, Guangzhou 510080 (China)

    2010-10-15

    Objective: To investigate the potential usefulness of three-dimensional contrast-enhanced ultrasound (3D-CEUS) in evaluating the treatment response for liver cancer after local therapies. Methods: A total of 107 lesions in 95 consecutive patients with liver cancer underwent local therapies and thereafter received low acoustic power 3D-CEUS examination. The LOGIQ 9 ultrasound scanner and a volume transducer were used and the ultrasound contrast agent was SonoVue. The image quality of 3D-CEUS images was evaluated and the influence of 3D-CEUS to clinical outcome was investigated. Results: The image quality of 3D-CEUS was defined as high in 102 (102/107, 95.3%) lesions and common in 5 (5/107, 4.7%) lesions. 3D-CEUS did not change the diagnosis in any patient compared with 2D-CEUS. However, 3D-CEUS changed the management in 3 (2.8%) of 107 lesions, increased confidence but made no change in diagnosis in 85 (79.5%) lesions, added some information but did not change management or diagnosis in 15 (14.0%), and made no change in 4 (3.7%), respectively, in comparison with 2D-CEUS. Conclusion: 3D-CEUS enhances the diagnostic confidence in the majority of the patients and even changes the management in some patients. 3D-CEUS has potential usefulness in evaluating treatment response for liver cancer after local therapies.

  15. Dynamic contrast-enhanced MRI improves accuracy for detecting focal splenic involvement in children and adolescents with Hodgkin disease

    Energy Technology Data Exchange (ETDEWEB)

    Punwani, Shonit; Taylor, Stuart A.; Halligan, Steve [University College London, Centre for Medical Imaging, London (United Kingdom); University College London Hospital, Department of Radiology, London (United Kingdom); Cheung, King Kenneth; Skipper, Nicholas [University College London, Centre for Medical Imaging, London (United Kingdom); Bell, Nichola; Humphries, Paul D. [University College London Hospital, Department of Radiology, London (United Kingdom); Bainbridge, Alan [University College London, Department of Medical Physics and Bioengineering, London (United Kingdom); Groves, Ashley M.; Hain, Sharon F.; Ben-Haim, Simona [University College Hospital, Institute of Nuclear Medicine, London (United Kingdom); Shankar, Ananth; Daw, Stephen [University College London Hospital, Department of Paediatrics, London (United Kingdom)

    2013-08-15

    Accurate assessment of splenic disease is important for staging Hodgkin lymphoma. The purpose of this study was to assess T2-weighted imaging with and without dynamic contrast-enhanced (DCE) MRI for evaluation of splenic Hodgkin disease. Thirty-one children with Hodgkin lymphoma underwent whole-body T2-weighted MRI with supplementary DCE splenic imaging, and whole-body PET-CT before and following chemotherapy. Two experienced nuclear medicine physicians derived a PET-CT reference standard for splenic disease, augmented by follow-up imaging. Unaware of the PET-CT, two experienced radiologists independently evaluated MRI exercising a locked sequential read paradigm (T2-weighted then DCE review) and recorded the presence/absence of splenic disease at each stage. Performance of each radiologist was determined prior to and following review of DCE-MRI. Incorrect MRI findings were ascribed to reader (lesion present on MRI but missed by reader) or technical (lesion not present on MRI) error. Seven children had splenic disease. Sensitivity/specificity of both radiologists for the detection of splenic involvement using T2-weighted images alone was 57%/100% and increased to 100%/100% with DCE-MRI. There were three instances of technical error on T2-weighted imaging; all lesions were visible on DCE-MRI. T2-weighted imaging when complemented by DCE-MRI imaging may improve evaluation of Hodgkin disease splenic involvement. (orig.)

  16. Dynamic contrast-enhanced MRI improves accuracy for detecting focal splenic involvement in children and adolescents with Hodgkin disease

    International Nuclear Information System (INIS)

    Punwani, Shonit; Taylor, Stuart A.; Halligan, Steve; Cheung, King Kenneth; Skipper, Nicholas; Bell, Nichola; Humphries, Paul D.; Bainbridge, Alan; Groves, Ashley M.; Hain, Sharon F.; Ben-Haim, Simona; Shankar, Ananth; Daw, Stephen

    2013-01-01

    Accurate assessment of splenic disease is important for staging Hodgkin lymphoma. The purpose of this study was to assess T2-weighted imaging with and without dynamic contrast-enhanced (DCE) MRI for evaluation of splenic Hodgkin disease. Thirty-one children with Hodgkin lymphoma underwent whole-body T2-weighted MRI with supplementary DCE splenic imaging, and whole-body PET-CT before and following chemotherapy. Two experienced nuclear medicine physicians derived a PET-CT reference standard for splenic disease, augmented by follow-up imaging. Unaware of the PET-CT, two experienced radiologists independently evaluated MRI exercising a locked sequential read paradigm (T2-weighted then DCE review) and recorded the presence/absence of splenic disease at each stage. Performance of each radiologist was determined prior to and following review of DCE-MRI. Incorrect MRI findings were ascribed to reader (lesion present on MRI but missed by reader) or technical (lesion not present on MRI) error. Seven children had splenic disease. Sensitivity/specificity of both radiologists for the detection of splenic involvement using T2-weighted images alone was 57%/100% and increased to 100%/100% with DCE-MRI. There were three instances of technical error on T2-weighted imaging; all lesions were visible on DCE-MRI. T2-weighted imaging when complemented by DCE-MRI imaging may improve evaluation of Hodgkin disease splenic involvement. (orig.)

  17. Contrast-enhanced MRI in breast cancer patients eligible for breast-conserving therapy: complementary value for subgroups of patients

    International Nuclear Information System (INIS)

    Deurloo, Eline E.; Klein Zeggelink, William F.A.; Teertstra, H. Jelle; Muller, Sara H.; Gilhuijs, Kenneth G.A.; Peterse, Johannes L.; Rutgers, Emiel J. T.; Bartelink, Harry

    2006-01-01

    The aim of this study was to identify patients prior to breast-conserving therapy (BCT) who have complementary value of contrast-enhanced magnetic resonance imaging (MRI) over conventional imaging in the assessment of tumor extent. All patients were eligible for BCT according to conventional imaging, and underwent preoperative MRI as part of this study. One hundred and sixty-five patients (166 tumors) were included. MRI was defined to have complementary value if conventional imaging underestimated or overestimated tumor extent (by more than 10 mm compared to histology) and MRI assessed the extent accurately. Logistic regression was employed to identify characteristics that are predictive of the complementary value of preoperative MRI. MRI had complementary value in 39 cases (23%). Patients <58 years old with irregular lesion margins at mammography and discrepancy in tumor extent by more than 10 mm between mammography and ultrasonography had a 3.2 x higher chance of accurate assessment at MRI (positive predictive value 50%, negative predictive value 84%, p=0.0002). Preoperative MRI in patients eligible for BCT is more accurate than conventional imaging in the assessment of tumor extent in approximately one out of four patients. Subgroups of patients in whom MRI has complementary value may be defined by the differences in clinical and imaging features. (orig.)

  18. Clinical value of elasticity imaging and contrast-enhanced ultrasound in the diagnosis of papillary thyroid microcarcinoma.

    Science.gov (United States)

    Li, Fengsheng; Zhang, Jianlei; Wang, Yunmei; Liu, Liwen

    2015-09-01

    The present study aimed to evaluate the value of elasticity imaging and contrast-enhanced ultrasonography (CEUS) in the differential diagnosis of papillary thyroid microcarcinoma (TMC). In total, 73 patients exhibiting a total of 80 small thyroid nodules, which were difficult to diagnose using conventional ultrasonography, underwent elasticity imaging and CEUS. The diagnostic findings were subsequently clarified by intraoperative and pathological examination, and the accuracy of the 2 diagnostic methods was compared. The correct diagnostic rate of CEUS was 85% (68/80 nodules), of which 6 cases of TMC were misdiagnosed as benign lesions and 6 benign nodules were misdiagnosed as TMC. By contrast, the accuracy rate of the elasticity imaging, based on the 5-point diagnostic method, was 92.5% (74/80 nodules), of which 3 cases of TMC were misdiagnosed as benign nodules and 3 benign nodules were misdiagnosed as TMC. Furthermore, elasticity imaging in the diagnosis of TMC was determined to have sensitivity, specificity and accuracy rates of 94.0, 90.0 and 92.5%, respectively, whereas the corresponding rates for CEUS were 88.0, 80.0 and 85.0%, respectively. Thus, ultrasonographic elasticity imaging exhibited significant advantages in the diagnosis of TMC compared with CEUS (Padvantage in the diagnosis of TMC; however, an elasticity score of ≥3 is of high clinical value as a diagnostic criterion for TMC.

  19. Quantitative estimation of renal function with dynamic contrast-enhanced MRI using a modified two-compartment model.

    Directory of Open Access Journals (Sweden)

    Bin Chen

    Full Text Available To establish a simple two-compartment model for glomerular filtration rate (GFR and renal plasma flow (RPF estimations by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI.A total of eight New Zealand white rabbits were included in DCE-MRI. The two-compartment model was modified with the impulse residue function in this study. First, the reliability of GFR measurement of the proposed model was compared with other published models in Monte Carlo simulation at different noise levels. Then, functional parameters were estimated in six healthy rabbits to test the feasibility of the new model. Moreover, in order to investigate its validity of GFR estimation, two rabbits underwent acute ischemia surgical procedure in unilateral kidney before DCE-MRI, and pixel-wise measurements were implemented to detect the cortical GFR alterations between normal and abnormal kidneys.The lowest variability of GFR and RPF measurements were found in the proposed model in the comparison. Mean GFR was 3.03±1.1 ml/min and mean RPF was 2.64±0.5 ml/g/min in normal animals, which were in good agreement with the published values. Moreover, large GFR decline was found in dysfunction kidneys comparing to the contralateral control group.Results in our study demonstrate that measurement of renal kinetic parameters based on the proposed model is feasible and it has the ability to discriminate GFR changes in healthy and diseased kidneys.

  20. Effect of parallel radiofrequency transmission on arterial input function selection in dynamic contrast-enhanced 3 Tesla pelvic MRI.

    Science.gov (United States)

    Chafi, Hatim; Elias, Saba N; Nguyen, Huyen T; Friel, Harry T; Knopp, Michael V; Guo, BeiBei; Heymsfield, Steven B; Jia, Guang

    2016-01-01

    To evaluate whether parallel radiofrequency transmission (mTX) can improve the symmetry of the left and right femoral arteries in dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) of prostate and bladder cancer. Eighteen prostate and 24 bladder cancer patients underwent 3.0 Tesla DCE-MRI scan with a single transmission channel coil. Subsequently, 21 prostate and 21 bladder cancer patients were scanned using the dual channel mTX upgrade. The precontrast signal ( S0) and the maximum enhancement ratio (MER) were measured in both the left and the right femoral arteries. Within the patient cohort, the ratio of S0 and MER in the left artery to that in the right artery ( S0_LR, MER_LR) was calculated with and without the use of mTX. Left to right asymmetry indices for S0 ( S0_LRasym) and MER ( MER_LRasym) were defined as the absolute values of the difference between S0_LR and 1, and the difference between MER_LR and 1, respectively. S0_LRasym, and MER_LRasym were 0.21 and 0.19 for prostate cancer patients with mTX, and 0.43 and 0.45 for the ones imaged without it (P enhancement. © 2015 Wiley Periodicals, Inc.

  1. Differences in perfusion parameters between upper and lower lumbar vertebral segments with dynamic contrast-enhanced MRI (DCE MRI)

    Energy Technology Data Exchange (ETDEWEB)

    Savvopoulou, Vasiliki; Vlahos, Lampros; Moulopoulos, Lia Angela [University of Athens, Areteion Hospital, Department of Radiology, Medical School, Athens (Greece); Maris, Thomas G. [University of Crete, Deparment of Medical Physics, Faculty of Medicine, Heraklion (Greece)

    2008-09-15

    To investigate the influence of age, sex and spinal level on perfusion parameters of normal lumbar bone marrow with dynamic contrast-enhanced MRI (DCE MRI). Sixty-seven subjects referred for evaluation of low back pain or sciatica underwent DCE MRI of the lumbar spine. After subtraction of dynamic images, a region of interest (ROI) was placed on each lumbar vertebral body of all subjects, and time intensity curves were generated. Consequently, perfusion parameters were calculated. Statistical analysis was performed to search for perfusion differences among lumbar vertebrae and in relation to age and sex. Upper (L1, L2) and lower (L3, L4, L5) vertebrae showed significant differences in perfusion parameters (p<0.05). Vertebrae of subjects younger than 50 years showed significantly higher perfusion compared to vertebrae of older ones (p<0.05). Vertebrae of females demonstrated significantly increased perfusion compared to those of males of corresponding age (p<0.05). All perfusion parameters, except for washout (WOUT), showed a mild linear correlation with age. Time to maximum slope (TMSP) and time to peak (TTPK) showed the same correlation with sex (0.22

  2. Intraprocedural contrast-enhanced ultrasound (CEUS) in liver percutaneous radiofrequency ablation: clinical impact and health technology assessment.

    Science.gov (United States)

    Mauri, Giovanni; Porazzi, Emanuele; Cova, Luca; Restelli, Umberto; Tondolo, Tania; Bonfanti, Marzia; Cerri, Anna; Ierace, Tiziana; Croce, Davide; Solbiati, Luigi

    2014-04-01

    To assess the clinical and the economic impacts of intraprocedural use of contrast-enhanced ultrasound (CEUS) in patients undergoing percutaneous radiofrequency ablation for small (impact, cost effectiveness, and budget, organisational and equity impacts were evaluated and compared with standard treatment without intraprocedural CEUS using the health technology assessment approach. Intraprocedural CEUS detected incomplete ablation in 34/93 (36.5 %) patients, who underwent additional treatment during the same session. At 24-h, complete ablation was found in 88/93 (94.6 %) patients. Thus, a second session of treatment was spared in 29/93 (31.1 %) patients. Cost-effectiveness analysis revealed an advantage for the use of intraprocedural CEUS in comparison with standard treatment (4,639 vs 6,592) with a 21.9 % reduction of the costs to treat the whole sample. Cost per patient for complete treatment was  4,609 versus  5,872 respectively. The introduction of intraprocedural CEUS resulted in a low organisational impact, and in a positive impact on equity Intraprocedural use of CEUS has a relevant clinical impact, reducing the number of re-treatments and the related costs per patient. • CEUS allows to immediately asses the result of ablation. • Intraprocedural CEUS decreases the number of second ablative sessions. • Intraprocedural CEUS may reduce cost per patient for complete treatment. • Use of intraprocedural CEUS may reduce hospital budget. • Its introduction has low organisational impact, and relevant impact on equity.

  3. Multidetector CT venography and contrast-enhanced MR venography of the inferior mesenteric vein in paediatric extrahepatic portal vein obstruction

    International Nuclear Information System (INIS)

    Chennur, Vikash SrinivasaiahSetty; Sharma, Raju; Gamanagatti, Shivanand; Gupta, Arun Kumar; Bhatnagar, Veereshwar; Vishnubhatla, Sreenivas

    2011-01-01

    Extrahepatic portal vein obstruction (EHPVO) is a common cause of paediatric portal hypertension and the only permanent treatment is shunt surgery. The inferior mesenteric vein (IMV) is a portal venous channel that can be used for the shunt when the splenic vein/superior mesenteric vein is thrombosed or when a lienorenal shunt is not possible. To compare MDCT venography (MDCTV) and contrast-enhanced MR venography (CEMRV) for visualisation of the IMV in children with EHPVO. This was a prospective study of 26 children (4-12 years, median 10 years) who underwent MDCTV and CEMRV. The IMV visualisation was graded using 4- and 2-point scales and the difference in visualisation was assessed by calculating the exact significance probability (P). The IMV was visualised in all children on MDCTV and 25/26 children on CEMRV (96%). The images were diagnostic in 23/26 children (88%) on MDCTV and in 18/26 (69%) children on CEMRV (P = 0.063). MDCTV and CEMRV are comparable for IMV visualisation with a tendency toward MDCTV being superior. (orig.)

  4. Multidetector CT venography and contrast-enhanced MR venography of the inferior mesenteric vein in paediatric extrahepatic portal vein obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Chennur, Vikash SrinivasaiahSetty; Sharma, Raju; Gamanagatti, Shivanand; Gupta, Arun Kumar [All India Institute of Medical Sciences (AIIMS), Department of Radiology, New Delhi (India); Bhatnagar, Veereshwar [AIIMS, Department of Paediatric Surgery, New Delhi (India); Vishnubhatla, Sreenivas [AIIMS, Department of Biostatistics, New Delhi (India)

    2011-03-15

    Extrahepatic portal vein obstruction (EHPVO) is a common cause of paediatric portal hypertension and the only permanent treatment is shunt surgery. The inferior mesenteric vein (IMV) is a portal venous channel that can be used for the shunt when the splenic vein/superior mesenteric vein is thrombosed or when a lienorenal shunt is not possible. To compare MDCT venography (MDCTV) and contrast-enhanced MR venography (CEMRV) for visualisation of the IMV in children with EHPVO. This was a prospective study of 26 children (4-12 years, median 10 years) who underwent MDCTV and CEMRV. The IMV visualisation was graded using 4- and 2-point scales and the difference in visualisation was assessed by calculating the exact significance probability (P). The IMV was visualised in all children on MDCTV and 25/26 children on CEMRV (96%). The images were diagnostic in 23/26 children (88%) on MDCTV and in 18/26 (69%) children on CEMRV (P = 0.063). MDCTV and CEMRV are comparable for IMV visualisation with a tendency toward MDCTV being superior. (orig.)

  5. Contrast-enhanced spectral mammography: Does mammography provide additional clinical benefits or can some radiation exposure be avoided?

    Science.gov (United States)

    Fallenberg, Eva Maria; Dromain, Clarisse; Diekmann, Felix; Renz, Diane M; Amer, Heba; Ingold-Heppner, Barbara; Neumann, Avidan U; Winzer, Klaus J; Bick, Ulrich; Hamm, Bernd; Engelken, Florian

    2014-07-01

    The purpose of this study was to compare contrast-enhanced spectral mammography (CESM) with mammography (MG) and combined CESM + MG in terms of detection and size estimation of histologically proven breast cancers in order to assess the potential to reduce radiation exposure. A total of 118 patients underwent MG and CESM and had final histological results. CESM was performed as a bilateral examination starting 2 min after injection of iodinated contrast medium. Three independent blinded radiologists read the CESM, MG, and CESM + MG images with an interval of at least 4 weeks to avoid case memorization. Sensitivity and size measurement correlation and differences were calculated, average glandular dose (AGD) levels were compared, and breast densities were reported. Fisher's exact and Wilcoxon tests were performed. A total of 107 imaging pairs were available for analysis. Densities were ACR1: 2, ACR2: 45, ACR3: 42, and ACR4: 18. Mean AGD was 1.89 mGy for CESM alone, 1.78 mGy for MG, and 3.67 mGy for the combination. In very dense breasts, AGD of CESM was significantly lower than MG. Sensitivity across readers was 77.9 % for MG alone, 94.7 % for CESM, and 95 % for CESM + MG. Average tumor size measurement error compared to postsurgical pathology was -0.6 mm for MG, +0.6 mm for CESM, and +4.5 mm for CESM + MG (p radiation dose, especially in patients with dense breasts.

  6. Lymphoma and inflammation in the orbit: Diagnostic performance with diffusion-weighted imaging and dynamic contrast-enhanced MRI.

    Science.gov (United States)

    Sun, Bo; Song, Liyuan; Wang, Xinyan; Li, Jing; Xian, Junfang; Wang, Feifei; Tan, Pan

    2017-05-01

    To investigate the diagnostic performance of diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI), and the combination of both in the differential diagnosis of lymphoma and inflammation in the orbit. This retrospective study was approved by the Institutional Review Board and the informed consent requirement was waived. A total of 53 patients underwent preoperative 3T MRI. Parameters of DWI and DCE MRI were evaluated in these 30 patients with orbital lymphoma and 23 patients with orbital inflammation. The diagnostic performance was evaluated using receiver operating characteristic curve analysis. Apparent diffusion coefficient (ADC) values and parameters derived from DCE MRI of orbital lymphoma and orbital inflammation differed significantly (ADC, T max , contrast index [CI], enhancement ratio [ER], and washout ratio [WR]: P inflammation (P = 0.016 for reviewer 1; P = 0.001 for reviewer 2). The combination of DWI and DCE MRI can improve diagnostic performance in differentiating lymphoma from inflammation in the orbit compared with DWI alone. 3 J. MAGN. RESON. IMAGING 2017;45:1438-1445. © 2016 International Society for Magnetic Resonance in Medicine.

  7. MR evaluation of biliary-enteric anastomotic stricture: does contrast-enhanced T1W MRC provide additional information?

    Science.gov (United States)

    Kandasamy, Devasenathipathy; Sharma, Raju; Seith Bhalla, Ashu; Gamanagatti, Shivanand R; Srivastava, Deep N; Sahni, Peush; Kumar, Rakesh

    2011-09-01

    To compare T2W-MRCP and T1W contrast-enhanced MRC (CE-MRC) using Gd-BOPTA for evaluation of biliary-enteric anastomotic (BEA) stricture. Twenty-one patients who were suspected to have BEA stricture underwent T2W-MRCP and CE-MRC on a 1.5T scanner. Images were evaluated for evidence of anastomotic stricture. Composite gold standard was used including the findings on percutaneous transhepatic cholangiogram or percutaneous transhepatic biliary dilatation, surgery, alkaline phosphatase level and clinical follow-up. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of T2W-MRCP for the diagnosis of anastomotic stricture were 94.4%, 80%, 94.4% and 80% respectively. On CE-MRC, biliary excretion was seen in only 60.87% anastomoses and only these were taken for analysis. The sensitivity, specificity, PPV and NPV of CE-MRC for the diagnosis of anastomotic stricture were 40%, 75%, 80% and 33.3%. The combined evaluation of T2W-MRCP and CE-MRC showed sensitivity, specificity, PPV and NPV of 83.3%, 80%, 93.8% and 57.1%. At present, T2W-MRCP is still the diagnostic modality of choice in the evaluation of patients with BEA stricture and the usage of Gd-BOPTA enhanced MRC is inappropriate in this setting. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  8. Application of contrast-enhanced ultrasound in the diagnosis of solid pancreatic lesions—A comparison of conventional ultrasound and contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Zhihui, E-mail: fanzhihui_1026@163.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Li, Ying, E-mail: 18901033676@126.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Radiology, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Yan, Kun, E-mail: ydbz@sina.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Wu, Wei, E-mail: wuwei@163.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Yin, Shanshan, E-mail: yshshmd@yahoo.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Yang, Wei, E-mail: weiwei02032001@gmail.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Xing, Baocai, E-mail: xinbaocai88@sina.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Hepatic Biliary and Pancreatic Surgery, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); and others

    2013-09-15

    Objective: To explore the diagnostic value of contrast-enhanced ultrasound (CEUS) by comparison with conventional ultrasound (US) and contrast-enhanced CT (CECT) in solid pancreatic lesions. Method: Ninety patients with solid pancreatic focal lesions were enrolled, including 36 cases of pancreatic carcinoma, 28 cases of pancreatitis, 6 cases of pancreatic neuroendocrine tumor, 12 cases of solid pseudopapillary tumor of the pancreas, 6 cases of pancreatic metastases, 1 case of cavernous hemolymphangioma and 1 case of lymphoma. US and CEUS were applied respectively for the diagnosis of a total of 90 cases of solid pancreatic lesions. The diagnostic results were scored on a 5-point scale. Results of CEUS were compared with CECT. Results: (1) 3-score cases (undetermined) diagnosed by CEUS were obviously fewer than that of US, while the number of 1-score (definitely benign) and 5-score (definitely malignant) cases diagnosed by CEUS was significantly more than that of US. There was a significant difference in the distribution of final scores using the two methods (p < 0.001). The overall diagnostic accuracies of the 90 cases for CEUS and US were 83.33% and 44.44%, respectively, which indicated an obvious advantage for CEUS (p < 0.001). (2) The diagnostic consistency among three ultrasound doctors: the kappa values calculated for US were 0.537, 0.444 and 0.525, compared with 0.748, 0.645 and 0.795 for CEUS. The interobserver agreement for CEUS was higher than that for US. (3) The sensitivity, specificity and accuracy of the diagnosis of pancreatic carcinoma with CEUS and CECT were 91.7% and 97.2%, 87.0% and 88.9%, and 88.9% and 92.2%, respectively, while for the diagnosis of pancreatitis, the corresponding indices were 82.1% and 67.9%, 91.9% and 100%, and 88.9% and 90%, respectively, showing no significant differences (p > 0.05). Conclusion: CEUS has obvious superiority over conventional US in the general diagnostic accuracy of solid pancreatic lesions and in the

  9. Three-dimensional contrast enhanced ultrasound score and dynamic contrast-enhanced magnetic resonance imaging score in evaluating breast tumor angiogenesis: Correlation with biological factors

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Wan-Ru, E-mail: jiawanru@126.com [Department of Diagnostic Ultrasound, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, No. 197 Rui Jin 2nd Road, Shanghai 200025 (China); Chai, Wei-Min, E-mail: chai_weimin@yahoo.com.cn [Department of Radiology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, No. 197 Rui Jin 2nd Road, Shanghai 200025 (China); Tang, Lei, E-mail: jessietang1003@163.com [Department of Diagnostic Ultrasound, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, No. 197 Rui Jin 2nd Road, Shanghai 200025 (China); Wang, Yi, E-mail: xiatian.0602@163.com [Department of Diagnostic Ultrasound, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, No. 197 Rui Jin 2nd Road, Shanghai 200025 (China); Fei, Xiao-Chun, E-mail: xcf0222@163.com [Department of Pathology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, No. 197 Rui Jin 2nd Road, Shanghai 200025 (China); Han, Bao-San, E-mail: hanbaosan@126.com [Department of Comprehensive Breast Health Center, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, No. 197 Rui Jin 2nd Road, Shanghai 200025 (China); Chen, Man, E-mail: lucyjia1370@126.com [Department of Diagnostic Ultrasound, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, No. 197 Rui Jin 2nd Road, Shanghai 200025 (China)

    2014-07-15

    Objective: To explore the clinical value of three-dimensional contrast enhanced ultrasound (3D-CEUS) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) score systems in evaluating breast tumor angiogenesis by comparing their diagnostic efficacy and correlation with biological factors. Methods: 3D-CEUS was performed in 183 patients with breast tumors by Esaote Mylab90 with SonoVue (Bracco, Italy), DCE-MRI was performed on a dedicated breast magnetic resonance imaging (DBMRI) system (Aurora Dedicated Breast MRI Systems, USA) with a dedicated breast coil. 3D-CEUS and DCE-MRI score systems were created based on tumor perfusion and vascular characteristics. Microvessel density (MVD), vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMP-2, MMP-9) expression were measured by immunohistochemistry. Results: Pathological results showed 35 benign and 148 malignant breast tumors. MVD (P = 0.000, r = 0.76), VEGF (P = 0.000, r = 0.55), MMP-2 (P = 0.000, r = 0.39) and MMP-9 (P = 0.000, r = 0.41) expression were all significantly different between benignity and malignancy. Regarding 3D-CEUS 4 points as cutoff value, the sensitivity, specificity and accuracy were 85.1%, 94.3% and 86.9%, respectively, and correlated well with MVD (P = 0.000, r = 0.50), VEGF (P = 0.000, r = 0.50), MMP-2 (P = 0.000, r = 0.50) and MMP-9 (P = 0.000, r = 0.66). Taking DCE-MRI 5 points as cutoff value, the sensitivity, specificity and accuracy were 86.5%, 94.3% and 88.0%, respectively and also correlated well with MVD (P = 0.000, r = 0.52), VEGF (P = 0.000, r = 0.44), MMP-2 (P = 0.000, r = 0.42) and MMP-9 (P = 0.000, r = 0.35). Conclusions: 3D-CEUS score system displays inspiring diagnostic performance and good agreement with DCE-MRI scoring. Moreover, both score systems correlate well with MVD, VEGF, MMP-2 and MMP-9 expression, and thus have great potentials in tumor angiogenesis evaluation.

  10. Application of contrast-enhanced ultrasound in the diagnosis of solid pancreatic lesions—A comparison of conventional ultrasound and contrast-enhanced CT

    International Nuclear Information System (INIS)

    Fan, Zhihui; Li, Ying; Yan, Kun; Wu, Wei; Yin, Shanshan; Yang, Wei; Xing, Baocai

    2013-01-01

    Objective: To explore the diagnostic value of contrast-enhanced ultrasound (CEUS) by comparison with conventional ultrasound (US) and contrast-enhanced CT (CECT) in solid pancreatic lesions. Method: Ninety patients with solid pancreatic focal lesions were enrolled, including 36 cases of pancreatic carcinoma, 28 cases of pancreatitis, 6 cases of pancreatic neuroendocrine tumor, 12 cases of solid pseudopapillary tumor of the pancreas, 6 cases of pancreatic metastases, 1 case of cavernous hemolymphangioma and 1 case of lymphoma. US and CEUS were applied respectively for the diagnosis of a total of 90 cases of solid pancreatic lesions. The diagnostic results were scored on a 5-point scale. Results of CEUS were compared with CECT. Results: (1) 3-score cases (undetermined) diagnosed by CEUS were obviously fewer than that of US, while the number of 1-score (definitely benign) and 5-score (definitely malignant) cases diagnosed by CEUS was significantly more than that of US. There was a significant difference in the distribution of final scores using the two methods (p < 0.001). The overall diagnostic accuracies of the 90 cases for CEUS and US were 83.33% and 44.44%, respectively, which indicated an obvious advantage for CEUS (p < 0.001). (2) The diagnostic consistency among three ultrasound doctors: the kappa values calculated for US were 0.537, 0.444 and 0.525, compared with 0.748, 0.645 and 0.795 for CEUS. The interobserver agreement for CEUS was higher than that for US. (3) The sensitivity, specificity and accuracy of the diagnosis of pancreatic carcinoma with CEUS and CECT were 91.7% and 97.2%, 87.0% and 88.9%, and 88.9% and 92.2%, respectively, while for the diagnosis of pancreatitis, the corresponding indices were 82.1% and 67.9%, 91.9% and 100%, and 88.9% and 90%, respectively, showing no significant differences (p > 0.05). Conclusion: CEUS has obvious superiority over conventional US in the general diagnostic accuracy of solid pancreatic lesions and in the

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

    NARCIS (Netherlands)

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

    2000-01-01

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

  12. Contrast-enhanced magnetic resonance venography in pediatric patients with chronic kidney disease: initial experience with ferumoxytol

    International Nuclear Information System (INIS)

    Luhar, Aarti; Khan, Sarah; Ghahremani, Shahnaz; Griggs, Rachel; Hall, Theodore R.; Finn, J.P.; Zaritsky, Joshua; Salusky, Isidro

    2016-01-01

    Ferumoxytol is an ultra-small superparamagnetic iron oxide (USPIO) particle that is FDA-approved for parenteral treatment of iron deficiency anemia in adults with chronic kidney disease. Because of the association between gadolinium-based contrast agents and nephrogenic systemic fibrosis in patients with severe chronic kidney disease, we sought to evaluate the diagnostic role of ferumoxytol-enhanced MR venography in children with chronic kidney disease. Twenty children underwent 22 high-resolution ferumoxytol-enhanced MR venography examinations at 3.0 T. High-resolution 3-D contrast-enhanced imaging was performed at a minimum of 3 time points following injection of ferumoxytol at a total dose of 4 mg/kg. Two blinded pediatric radiologists independently scored six named veins on ferumoxytol-enhanced MR venography examinations according to a three-point subjective score, where a score ≥2 was considered diagnostic. Additionally, all relevant venous structures in the included field of view were analyzed for occlusive or non-occlusive thrombosis, compression and presence of collaterals. All patients underwent ferumoxytol-enhanced MR venography successfully and without adverse event. The overall scores of the reviewing radiologists for all venous structures were 2.7-2.9. In all cases, the reviewers were confident basing their diagnoses on the ferumoxytol-enhanced MR venography findings. In 12 of 22 examinations, findings on follow-up imaging or invasive procedures were available to correlate with the findings on ferumoxytol-enhanced MR venography. There was complete concordance between the findings from follow-up imaging and invasive procedures with findings from ferumoxytol-enhanced MR venography. Ferumoxytol holds promise as a powerful alternative to gadolinium-based contrast agents for reliable, high-resolution MR venography in children with chronic kidney disease. (orig.)

  13. Dynamic contrast-enhanced magnetic resonance imaging can assess vascularity within fracture non-unions and predicts good outcome.

    Science.gov (United States)

    Schoierer, Oliver; Bloess, Konstantin; Bender, Daniel; Burkholder, Iris; Kauczor, Hans-Ulrich; Schmidmaier, Gerhard; Weber, Marc-André

    2014-02-01

    To prospectively evaluate whether dynamic contrast-enhanced (DCE) MRI can assess vascularity within non-unions and predicts clinical outcome in combination with the clinical Non-Union Scoring System (NUSS). Fifty-eight patients with non-unions of extremities on CT underwent 3-T DCE MRI. Signal intensity curves obtained from a region-of-interest analysis were subdivided into those with more intense contrast agent uptake within the non-union than in adjacent muscle (vascularised non-union) and those with similar or less contrast uptake. The pharmacokinetic parameters of the Tofts model K trans, K ep, iAUC and V e were correlated with union at CT 1 year later (n = 49). Despite inserted osteosynthetic material, DCE parameters could be evaluated in 57 fractures. The sensitivity/specificity of vascularised non-unions as an indicator of good outcome was 83.9%/50.0 % compared to 96.8%/33.3% using NUSS (n = 49). Logistic regression revealed a significant impact of NUSS on outcome (P = 0.04, odds ratio = 0.93). At first examination, median iAUC (initial area under the enhancement curve) for the ratio non-union/muscle was 10.28 in patients with good outcome compared with 3.77 in non-responders (P = 0.023). K trans, K ep and Ve within the non-union were not significantly different initially (n = 57) or 1 year later (n = 19). DCE MRI can assess vascularity in fracture non-unions. A vascularised non-union correlates with good outcome. • Dynamic contrast-enhanced magnetic resonance imaging can assess vascularity within bony non-unions. • Vascularised ununited fractures appear better at 1-year CT than poorly vascularised fractures. • Non-union healing after osteosynthesis or osteoinductive drugs fundamentally requires vascularity. • DCE MRI predicts treatment outcome better than the clinical Non-Union Scoring System. • DCE MRI is clinically feasible to predict treatment outcome in bony non-unions.

  14. Predicting IDH mutation status of intrahepatic cholangiocarcinomas based on contrast-enhanced CT features.

    Science.gov (United States)

    Zhu, Yong; Chen, Jun; Kong, Weiwei; Mao, Liang; Kong, Wentao; Zhou, Qun; Zhou, Zhengyang; Zhu, Bin; Wang, Zhongqiu; He, Jian; Qiu, Yudong

    2018-01-01

    To explore the difference in contrast-enhanced computed tomography (CT) features of intrahepatic cholangiocarcinomas (ICCs) with different isocitrate dehydrogenase (IDH) mutation status. Clinicopathological and contrast-enhanced CT features of 78 patients with 78 ICCs were retrospectively analysed and compared based on IDH mutation status. There were 11 ICCs with IDH mutation (11/78, 14.1%) and 67 ICCs without IDH mutation (67/78, 85.9%). IDH-mutated ICCs showed intratumoral artery more often than IDH-wild ICCs (p = 0.023). Most ICCs with IDH mutation showed rim and internal enhancement (10/11, 90.9%), while ICCs without IDH mutation often appeared diffuse (26/67, 38.8%) or with no enhancement (4/67, 6.0%) in the arterial phase (p = 0.009). IDH-mutated ICCs showed significantly higher CT values, enhancement degrees and enhancement ratios in arterial and portal venous phases than IDH-wild ICCs (all p IDH mutation, with an area under the curve of 0.798 (p = 0.002). ICCs with and without IDH mutation differed significantly in arterial enhancement mode, and the tumour enhancement degree on multiphase contrast-enhanced CT was helpful in predicting IDH mutation status. • IDH mutation occurred frequently in ICCs. • ICCs with and without IDH mutation differed significantly in arterial enhancement mode. • ICCs with IDH mutation enhanced more than those without IDH mutation. • Enhancement ratio and tumour CT value can predict IDH mutation status.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-09-15

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

  16. Differentiation between tuberculosis and lymphoma in mediastinal lymph nodes: Evaluation with contrast-enhanced MDCT.

    Science.gov (United States)

    Tang, S-S; Yang, Z-G; Deng, W; Shao, H; Chen, J; Wen, L-Y

    2012-09-01

    To determine the specific imaging criteria on contrast-enhanced multidetector computed tomography (MDCT) for differentiating between tuberculosis and lymphoma in mediastinal lymph nodes. The anatomical distribution and enhancement patterns of mediastinal lymph nodes on contrast-enhanced MDCT were reviewed in 37 patients with tuberculosis and 54 patients with lymphoma. Of the patients with lymphoma, 18 had Hodgkin's disease and 36 had non-Hodgkin's lymphoma. Region 10R was involved more often in tuberculosis than in Hodgkin's disease and non-Hodgkin's lymphoma. Region 6 had a higher tendency to be affected in Hodgkin's disease and non-Hodgkin's lymphoma compared with tuberculosis. Tuberculosis showed peripheral enhancement in 78% of cases, frequently with a multilocular appearance, compared to Hodgkin's disease and non-Hodgkin's lymphoma, which showed peripheral enhancement in only 6 and 3% of cases, respectively. Homogeneous enhancement was more commonly seen in lymphoma (83% for Hodgkin's disease, and 83% for non-Hodgkin's lymphoma) than in tuberculosis (8%). In the determination of tuberculosis, results showed that when a peripheral enhancement pattern was seen, sensitivity was 78%, specificity was 96%, and accuracy was 89%. In the determination of lymphoma, results showed that when a homogeneous enhancement pattern was seen, sensitivity was 83%, specificity was 92%, and accuracy was 87%. The findings of the present study indicate that specific anatomical distribution and enhancement patterns of lymphadenopathy shown on contrast-enhanced MDCT can be useful in differentiating tuberculosis from lymphoma of mediastinal lymph nodes. Copyright © 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  17. Local gray level S-curve transformation - A generalized contrast enhancement technique for medical images.

    Science.gov (United States)

    Gandhamal, Akash; Talbar, Sanjay; Gajre, Suhas; Hani, Ahmad Fadzil M; Kumar, Dileep

    2017-04-01

    Most medical images suffer from inadequate contrast and brightness, which leads to blurred or weak edges (low contrast) between adjacent tissues resulting in poor segmentation and errors in classification of tissues. Thus, contrast enhancement to improve visual information is extremely important in the development of computational approaches for obtaining quantitative measurements from medical images. In this research, a contrast enhancement algorithm that applies gray-level S-curve transformation technique locally in medical images obtained from various modalities is investigated. The S-curve transformation is an extended gray level transformation technique that results into a curve similar to a sigmoid function through a pixel to pixel transformation. This curve essentially increases the difference between minimum and maximum gray values and the image gradient, locally thereby, strengthening edges between adjacent tissues. The performance of the proposed technique is determined by measuring several parameters namely, edge content (improvement in image gradient), enhancement measure (degree of contrast enhancement), absolute mean brightness error (luminance distortion caused by the enhancement), and feature similarity index measure (preservation of the original image features). Based on medical image datasets comprising 1937 images from various modalities such as ultrasound, mammograms, fluorescent images, fundus, X-ray radiographs and MR images, it is found that the local gray-level S-curve transformation outperforms existing techniques in terms of improved contrast and brightness, resulting in clear and strong edges between adjacent tissues. The proposed technique can be used as a preprocessing tool for effective segmentation and classification of tissue structures in medical images. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Contrast-enhanced fat- suppression MR imaging of avascular necrosis of femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Tae Kyoung; Shim, Jae Chan; Lee, Ghi Jai; Jeon, Jeong Dong; Bang, Sun Woo; Kim, Ho Kyun [College of Medicine, Inje University, Seoul (Korea, Republic of)

    2000-02-01

    To evaluate the findings and role of contrast-enhanced fat suppression MR imaging in avascular necrosis (AVN) of the femoral head. In 15 patients with AVN of the femoral head, MR T1-weighted and T2-weighted images and contrast-enhanced fat-suppression T1-weighted images were obtained, and the findings were reviewed. Early and advanced groups were classified on the basis of clinical findings and imaging, and the enhancement pattern was classified as either type I, rim enhancement; type II, surrounding diffuse enhancement; type III, intralesional enhancement; or type IV, II + III. Twenty-four cases of AVN of the femoral head were detected; in nine patients, lesions were bilateral. Eight cases occurred in the early group and 16 in the advanced. All eight in the early group showed the 'double line sign' on T2-weighted images, with a type-I enhancement pattern. In the advanced group, type II (8/16) and type IV (8/16) enhancement patterns were seen. Among the cases showing the type-IV pattern, the intralesional enhancing area showed low signal intensity on T1-weighted images and isosignal intensity on T2-weighted in one case, and low signal intensity on T2-weighted in one case, and low signal intensity on T1-weighted images and high signal intensity on T2-weighted in the other cases. There was no difference in the extent of the disease before and after enhancement. Contrast-enhanced fat-suppression MR images may be helpful in evaluating the extent of AVN of the femoral head and predicting the histopathologic findings of the disease. (author)

  19. Diagnostic Accuracy of Dynamic Contrast Enhanced Magnetic Resonance Imaging in Characterizing Lung Masses

    Science.gov (United States)

    Inan, Nagihan; Arslan, Arzu; Donmez, Muhammed; Sarisoy, Hasan Tahsin

    2016-01-01

    Background Imaging plays a critical role not only in the detection, but also in the characterization of lung masses as benign or malignant. Objectives To determine the diagnostic accuracy of dynamic magnetic resonance imaging (MRI) in the differential diagnosis of benign and malignant lung masses. Patients and Methods Ninety-four masses were included in this prospective study. Five dynamic series of T1-weighted spoiled gradient echo (FFE) images were obtained, followed by a T1-weighted FFE sequence in the late phase (5th minutes). Contrast enhancement patterns in the early (25th second) and late (5th minute) phase images were evaluated. For the quantitative evaluation, signal intensity (SI)-time curves were obtained and the maximum relative enhancement, wash-in rate, and time-to-peak enhancement of masses in both groups were calculated. Results The early phase contrast enhancement patterns were homogeneous in 78.2% of the benign masses, while heterogeneous in 74.4% of the malignant tumors. On the late phase images, 70.8% of the benign masses showed homogeneous enhancement, while most of the malignant masses showed heterogeneous enhancement (82.4%). During the first pass, the maximum relative enhancement and wash-in rate values of malignant masses were significantly higher than those of the benign masses (P = 0.03 and 0.04, respectively). The cutoff value at 15% yielded a sensitivity of 85.4%, specificity of 61.2%, and positive predictive value of 68.7% for the maximum relative enhancement. Conclusion Contrast enhancement patterns and SI-time curve analysis of MRI are helpful in the differential diagnosis of benign and malignant lung masses. PMID:27703654

  20. Contrast Enhanced Ultrasound of the Kidneys: What Is It Capable of?

    Directory of Open Access Journals (Sweden)

    Demosthenes D. Cokkinos

    2013-01-01

    Full Text Available One of the many imaging uses of contrast enhanced ultrasound (CEUS is studying a wide variety of kidney pathology, due to its ability to detect microvascular blood flow in real time without affecting renal function. CEUS enables dynamic assessment and quantification of microvascularisation up to capillary perfusion. The objective of this paper is to briefly refresh basic knowledge of ultrasound (US contrast agents’ physical properties, to study technical details of CEUS scanning in the kidneys, and to review the commonest renal indications for CEUS, with imaging examples in comparison to baseline unenhanced US and computed tomography when performed. Safety matters and limitations of CEUS of the kidneys are also discussed.

  1. Posterior Urethra Rupture: Contrast-Enhanced Computed Tomography Scan and Urethrocystography Demonstrations

    Directory of Open Access Journals (Sweden)

    Wojciech Marks

    2012-01-01

    Full Text Available In the follow-up study of patients with pelvic fractures, rupture of the posterior urethra is registered in 3–25% of cases (Koraitim et al., 1996. The diagnostic gold standard for the assessment of hemodynamically stable trauma patients is contrast-enhanced CT scan, especially helical CT. Nevertheless, simultaneous suprapubic cystography and ascending urethrograms (the so-called up-and-downogram are the investigation of choice in assessing the site, severity, and length of urethral injuries. (Carlin and Resnick, 1995 This paper discusses the evaluation and diagnosis of urethral injury in multiple-trauma patient.

  2. Characterization of primary hepatic carcinosarcoma by contrast-enhanced ultrasonography: a case report.

    Science.gov (United States)

    Liu, Li-Ping; Yu, Xiao-Ling; Liang, Ping; Dong, Bao-Wei

    2014-02-14

    Primary hepatic carcinosarcoma is a rare tumor and is comprised of a mixture of carcinomatous and sarcomatous elements. We present a case of primary carcinosarcoma of the liver in a 59-year-old woman, which was confirmed by pathology following surgical resection. Using contrast-enhanced ultrasonography, the tumor showed peripheral nodular hyperenhancement in the arterial phase with two feeding arterial vessels and a large internal non-enhancing portion in the center. The peripheral nodular portion of the tumor showed hypoenhancement in the later phase.

  3. Accelerated free breathing ECG triggered contrast enhanced pulmonary vein magnetic resonance angiography using compressed sensing

    OpenAIRE

    Roujol, Sébastien; Foppa, Murilo; Basha, Tamer A; Akçakaya, Mehmet; Kissinger, Kraig V; Goddu, Beth; Berg, Sophie; Nezafat, Reza

    2014-01-01

    Background: To investigate the feasibility of accelerated electrocardiogram (ECG)-triggered contrast enhanced pulmonary vein magnetic resonance angiography (CE-PV MRA) with isotropic spatial resolution using compressed sensing (CS). Methods: Nineteen patients (59 ± 13 y, 11 M) referred for MR were scanned using the proposed accelerated free breathing ECG-triggered 3D CE-PV MRA sequence (FOV = 340 × 340 × 110 mm3, spatial resolution = 1.5 × 1.5 × 1.5 mm3, acquisition window = 140 ms at mid dia...

  4. Atypical focal non-neoplastic brain changes in neurofibromatosis type 1: mass effect and contrast enhancement

    International Nuclear Information System (INIS)

    Raininko, R.; Thelin, L.; Eeg-Olofsson, O.

    2001-01-01

    Abstract Children and young adults with neurofibromatosis type 1 often have small high-signal foci on T2-weighted images of the brain. We describe follow-up of two patients in whom one of the foci had atypical features, commonly regarded as signs of a neoplasm. In the first, one lesion showed temporary contrast enhancement and decreasing mass effect. The second developed an expanding lesion that increased minimally in size over 4.5 year's follow-up. The borderline between neoplastic and non-neoplastic lesions seems to be indistinct. (orig.)

  5. Water-dispersible ascorbic-acid-coated magnetite nanoparticles for contrast enhancement in MRI

    Science.gov (United States)

    Sreeja, V.; Jayaprabha, K. N.; Joy, P. A.

    2015-04-01

    Superparamagnetic iron oxide nanoparticles of size ~5 nm surface functionalized with ascorbic acid (vitamin C) form a stable dispersion in water with a hydrodynamic size of ~30 nm. The anti-oxidant property of ascorbic acid is retained after capping, as evidenced from the capability of converting methylene blue to its reduced leuco form. NMR relaxivity studies show that the ascorbic-acid-coated superparamagnetic iron oxide aqueous nanofluid is suitable as a contrast enhancement agent for MRI applications, coupled with the excellent biocompatibility and medicinal values of ascorbic acid.

  6. Comparison between fast contrast-enhanced MR angiography and DSA in diagnosing spinal cord vascular malformations

    International Nuclear Information System (INIS)

    Wang Wu; Li Minghua; Fang Chun; Wang Jue; Xiao Yunfeng

    2007-01-01

    Objective: To evaluate the diagnostic and clinical value of fast contrast-enhanced MR angiography (CE-MRA) with elliptic centric phase-encoding in spinal cord vascular malformations. Methods Fast three-dimensional contrast-enhanced MR angiography with elliptic centric phase-encoding and superconducting 1.5T system was applied prospectively in twenty-five consecutive patients with clinically suspected of spinal cord vascular malformations. All cases were performed with selective spinal digital subtraction angiography, including 18 cases treated by surgery and 2 of them with embolization before surgery, MR angiography follow up were undertaken in ten patients after surgery. Comparing fast contrast-enhanced MR angiography with DSA in diagnosing spinal cord vascular malformations included the origin of feeding artery, the feeding artery, the fistula or the nidus, the draining vein, and the vessel image quality based on the gold standard of selective spinal digital subtraction angiography. Results: Surgically proven diseases included spinal arteriovenous malformations(3 cases), spinal cord perimedullary arteriovenous fistulas (5 cases), spinal dural arteriovenous fistulas (8 cases), paravertebral arteriovenous fistulas (1 case), and spontaneous spinal epidural hematomas (2 eases). Comparing with DSA, the accuracy of MR angiography in diagnosing spinal cord vascular malformations; and detecting the origin of the feeding artery, the feeding artery, the shunt or the nidus and the draining vein were 93.8%, 92%, 96.2%, 100% and 100%, respectively. Overall the degree vascular enhencement were judged to be similar(P>0.05), but the vessel continuity of MRA was inferior to DSA (P<0.05). However, 9 cases of MRA showed no abnormal vascular malformation coinciding with those of surgery. Posttreatment MR angiography did not depict any abnormal vessels again. Conclusions: Fast three-dimensional contrast-enhanced MR angiography with elliptic centric phase-encoding may provide

  7. Contrast-enhanced Ultrasound of Kidneys in Children with Renal Failure

    Directory of Open Access Journals (Sweden)

    Jeevesh Kapur

    2015-06-01

    Full Text Available Ultrasound (US has been an important tool for evaluating and imaging renal pathology in children. Development of US contrast agents and dedicated software for the detection of microbubbles has given this radiological investigation a new dimension, especially in children with renal impairment. Application of contrast-enhanced US (CEUS brings US into the domain historically occupied by computed tomography and magnetic resonance imaging. We retrospectively studied nine children who had undergone CEUS (age range 3–16 years. This pictorial essay draws on our experience and illustrates the safety and accurate depiction of enhancement pattern of focal renal lesions.

  8. Coronary microembolization with normal epicardial coronary arteries and no visible infarcts on nitrobluetetrazolium chloride-stained specimens: Evaluation with cardiac magnetic resonance imaging in a swine model

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hang; Yun, Hong; Zeng, Meng Su [Dept. of Radiology, Zhongshan Hospital, Fudan University and Shanghai Institute of Medical Imaging, Shanghai (China); Ma, Jian Ying; Chen, Zhang Wei; Chang, Shu Fu [Dept. of Cardiology, Zhongshan Hospital, Fudan University and Shanghai Institute of Cardiovascular Diseases, Shanghai (China)

    2016-02-15

    To assess magnetic resonance imaging (MRI) features of coronary microembolization in a swine model induced by small-sized microemboli, which may cause microinfarcts invisible to the naked eye. Eleven pigs underwent intracoronary injection of small-sized microspheres (42 µm) and catheter coronary angiography was obtained before and after microembolization. Cardiac MRI and measurement of cardiac troponin T (cTnT) were performed at baseline, 6 hours, and 1 week after microembolization. Postmortem evaluation was performed after completion of the imaging studies. Coronary angiography pre- and post-microembolization revealed normal epicardial coronary arteries. Systolic wall thickening of the microembolized regions decreased significantly from 42.6 ± 2.0% at baseline to 20.3 ± 2.3% at 6 hours and 31.5 ± 2.1% at 1 week after coronary microembolization (p < 0.001 for both). First-pass perfusion defect was visualized at 6 hours but the extent was largely decreased at 1 week. Delayed contrast enhancement MRI (DE-MRI) demonstrated hyperenhancement within the target area at 6 hours but not at 1 week. The microinfarcts on gross specimen stained with nitrobluetetrazolium chloride were invisible to the naked eye and only detectable microscopically. Increased cTnT was observed at 6 hours and 1 week after microembolization. Coronary microembolization induced by a certain load of small-sized microemboli may result in microinfarcts invisible to the naked eye with normal epicardial coronary arteries. MRI features of myocardial impairment secondary to such microembolization include the decline in left ventricular function and myocardial perfusion at cine and first-pass perfusion imaging, and transient hyperenhancement at DE-MRI.

  9. Differentiation between ductal carcinoma in situ and mastopathy using dynamic contrast-enhanced magnetic resonance imaging and a model of contrast enhancement

    International Nuclear Information System (INIS)

    Nishiura, Motoko; Tamaki, Yasuhiro; Murase, Kenya

    2011-01-01

    The purpose of this study was to retrospectively evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to differentiate between ductal carcinoma in situ (DCIS) and mastopathy by analyzing their time-intensity curves (TICs) using the two-compartment pharmacokinetic model with an assumption of instantaneous injection of contrast medium (TCPM). After the pre-contrast MRI was performed using a 1.5 T MRI system, DCE-MRI was performed four times after the intravenous administration of contrast medium. We set the volumes of interest (VOIs) on the tumor and normal mammary gland, and obtained the TICs in these VOIs. We calculated the following parameters by fitting these TICs to the equation derived from TCPM; the initial slope of the TIC (Slope ini ), the area under the TIC (AUC), the time to peak enhancement (TTP) and the peak enhancement (PeakE). We calculated these parameters in both the lesion and normal mammary gland and the ratios of the parameters in the lesion to those in the normal gland (rSlope ini , rAUC, rTTP and rPeakE). There were significant differences in Slope ini (P = 0.009), PeakE (P = 0.019), rSlope ini (P = 0.010), and rTTP (P = 0.005) between DCIS and mastopathy. The areas under the receiver operating characteristic curve for Slope ini , PeakE, rSlope ini , and rTTP were 0.67 ± 0.06 (P = 0.009), 0.65 ± 0.06 (P = 0.019), 0.67 ± 0.06 (P = 0.01), and 0.68 ± 0.06 (P = 0.005), respectively. In conclusion, our results suggest that analysis of TICs obtained by DCE-MRI using TCPM appears to be useful for differentiating between DCIS and mastopathy.

  10. Comparison of arterial input functions measured from ultra-fast dynamic contrast enhanced MRI and dynamic contrast enhanced computed tomography in prostate cancer patients

    Science.gov (United States)

    Wang, Shiyang; Lu, Zhengfeng; Fan, Xiaobing; Medved, Milica; Jiang, Xia; Sammet, Steffen; Yousuf, Ambereen; Pineda, Federico; Oto, Aytekin; Karczmar, Gregory S.

    2018-02-01

    The purpose of this study was to evaluate the accuracy of arterial input functions (AIFs) measured from dynamic contrast enhanced (DCE) MRI following a low dose of contrast media injection. The AIFs measured from DCE computed tomography (CT) were used as ‘gold standard’. A total of twenty patients received CT and MRI scans on the same day. Patients received 120 ml Iohexol in DCE-CT and a low dose of (0.015 mM kg-1) of gadobenate dimeglumine in DCE-MRI. The AIFs were measured in the iliac artery and normalized to the CT and MRI contrast agent doses. To correct for different temporal resolution and sampling periods of CT and MRI, an empirical mathematical model (EMM) was used to fit the AIFs first. Then numerical AIFs (AIFCT and AIFMRI) were calculated based on fitting parameters. The AIFMRI was convolved with a ‘contrast agent injection’ function (AIFMRICON ) to correct for the difference between MRI and CT contrast agent injection times (~1.5 s versus 30 s). The results show that the EMMs accurately fitted AIFs measured from CT and MRI. There was no significant difference (p  >  0.05) between the maximum peak amplitude of AIFs from CT (22.1  ±  4.1 mM/dose) and MRI after convolution (22.3  ±  5.2 mM/dose). The shapes of the AIFCT and AIFMRICON were very similar. Our results demonstrated that AIFs can be accurately measured by MRI following low dose contrast agent injection.

  11. Quantitative contrast-enhanced ultrasonographic assessment of naturally occurring pancreatitis in dogs.

    Science.gov (United States)

    Lim, S Y; Nakamura, K; Morishita, K; Sasaki, N; Murakami, M; Osuga, T; Yokoyama, N; Ohta, H; Yamasaki, M; Takiguchi, M

    2015-01-01

    Quantitative contrast-enhanced ultrasonography (CEUS) can detect pancreatic perfusion changes in experimentally induced canine pancreatitis. However, its usefulness in detecting perfusion changes in naturally occurring pancreatitis is unclear. To determine the feasibility of using CEUS to detect pancreatic and duodenal perfusion changes in naturally occurring canine pancreatitis. Twenty-three client-owned dogs with pancreatitis, 12 healthy control dogs. Dogs diagnosed with pancreatitis were prospectively included. CEUS of the pancreas and duodenum were performed. Time-intensity curves were created from regions of interest in the pancreas and duodenum. Five perfusion parameters were obtained for statistical analyses: time to initial up-slope, peak time (Tp), time to wash-out (TTW), peak intensity (PI), and area under the curve (AUC). For the pancreas, Tp of the pancreatitis group was prolonged when compared to controls (62 ± 11 seconds versus 39 ± 13 seconds; P pancreatitis group when compared to controls. Contrast-enhanced ultrasonography can detect pancreatic perfusion changes in naturally occurring canine pancreatitis characterized by delayed peak with prolonged hyperechoic enhancement of the pancreas on CEUS. Additionally, duodenal perfusion changes secondary to pancreatitis were observed. Copyright © 2014 by the American College of Veterinary Internal Medicine.

  12. Contrast-enhanced color Doppler ultrasound characteristics in hypervascular breast tumors: comparison with MRI

    International Nuclear Information System (INIS)

    Alamo, L.; Fischer, U.

    2001-01-01

    The aim of this study was to evaluate the accuracy of contrast-enhanced color Doppler ultrasound (CE-US) in comparison with contrast-enhanced MR imaging (CE-MRI) in the discrimination of hypervascularized breast tumors. An additional CE-US of the breast was preoperatively performed in 40 patients with a hypervascular breast lesion detected on CE-MRI. The presence of blood flow signals and the morphological characteristics of the vessels in the breast lesions were evaluated pre- and post-contrast administration, as well as the dynamic aspects of the Doppler signal, including time interval to maximum signal enhancement and persistence of the signal enhancement. Twenty-three carcinomas and 17 fibroadenomas were explored. Considering initial signal enhancement > 100 % after the administration of contrast material as a criterion suggesting malignancy, CE-MRI showed a sensitivity of 100 % and a specificity of 76.5 % in the detection of malignant breast tumors. Color Doppler signals were consistently demonstrated in all carcinomas and in 68.7 % of fibroadenomas after the administration of Levovist, with CE-US showing a sensitivity of 95.6 % and a specificity of 5.9 %. Neither the mean number of vessels per tumor, nor the location of vessels, the time to maximum increase of the Doppler signal or the persistence of signal enhancement showed significant differences between benign and malignant lesions. Additional CE-US does not increase the low specificity of MRI in patients with hypervascularized breast tumors. (orig.)

  13. Contrast-Enhanced Ultrasound-Guided Radiofrequency Ablation of Renal Tumors

    Science.gov (United States)

    O’Neal, Dan; Cohen, Tal; Peterson, Cynthia

    2018-01-01

    Although only limited long-term studies evaluating thermal ablation of renal masses have been performed, it appears that thermal ablation has a comparable 5-year success rate to that of partial or total nephrectomy. This technique is often used in patients who are not good candidates for partial or total nephrectomy. Contrast-enhanced ultrasound (CEUS) has been recently approved by the Food and Drug Administration for characterization of focal liver lesions in adults and pediatric patients. CEUS can be used off label for renal applications and has been used for years in Europe and Asia. It has several advantages over contrast-enhanced computed tomography for use as the technique to guide and evaluate efficacy of thermal ablation of renal masses. These include the ability to visualize small amounts of enhancement, repeat dosing to evaluate efficacy of an ablation during a procedure, thin slice thickness, and real-time visualization. Ultrasound contrast is also non-nephrotoxic and non-hepatotoxic, allowing evaluation of patients with renal insufficiency. This article reviews the use of CEUS for the guidance and follow-up of thermal ablative procedures of renal masses. PMID:29468107

  14. Differentiation between tuberculosis and primary tumors in the adrenal gland: evaluation with contrast-enhanced CT

    International Nuclear Information System (INIS)

    Yang, Zhi-Gang; Guo, Ying-Kun; Li, Yuan; Min, Peng-Qiu; Yu, Jian-Qun; Ma, En-Sen

    2006-01-01

    The aim of the present study is to determine imaging criteria for differentiating tuberculosis from primary tumors in the adrenal gland on contrast-enhanced CT. Non-contrast and contrast-enhanced CT features in 108 patients with adrenal tuberculosis (n=34) and primary tumor (n=74) were retrospectively assessed for the location, size, calcification and enhancement patterns. The primary tumors included 41 adenomas, 11 pheochromocytomas, 4 carcinomas, 3 lymphomas, 6 myelolipomas, 6 ganglioneuromas, 2 neurilemmomas and 1 ganglioneuroblastoma. Biochemical investigation was performed for all patients. Of the tuberculosis cases, 31 (91%) invaded with bilateral involvement, while 7 (9%) of the primary tumors invaded with bilateral involvement (P<0.001). Tuberculosis often showed calcification (20 of 34; 59%), whereas primary tumors infrequently showed calcification (6 of 74; 8%; P<0.001). Low attenuation in the center with peripheral rim enhancement was more commonly seen in tuberculosis (16 of 34; 47%) than in primary tumors (7 of 74; 9%; P<0.001). In the determination of tuberculosis, the highest sensitivity (91%) and accuracy (91%) were obtained with bilateral involvement, and the highest specificity (99%) was obtained with the contour preserved. In the determination of primary tumors using a combination of having unilateral involvement and being mass-like, the outcome was a sensitivity of 91%, specificity of 94% and accuracy of 92%. CT findings can differentiate tuberculosis from a primary tumor of the adrenal glands with high sensitivity and an acceptable specificity when combined with the endocrinological examination. (orig.)

  15. Ultrasound modulated optical tomography contrast enhancement with non-linear oscillation of microbubbles.

    Science.gov (United States)

    Ruan, Haowen; Mather, Melissa L; Morgan, Stephen P

    2015-02-01

    Ultrasound modulated optical tomography (USMOT) is an imaging technique used to provide optical functional information inside highly scattering biological tissue. One of the challenges facing this technique is the low image contrast. A contrast enhancement imaging technique based on the non-linear oscillation of microbubbles is demonstrated to improve image contrast. The ultrasound modulated signal was detected using a laser pulse based speckle contrast detection system. Better understanding of the effects of microbubbles on the optical signals was achieved through simultaneous measurement of the ultrasound scattered by the microbubbles. The length of the laser pulse was found to affect the system response of the speckle contrast method with shorter pulses suppressing the fundamental ultrasound modulated optical signal. Using this property, image contrast can be enhanced by detection of the higher harmonic ultrasound modulated optical signals due to nonlinear oscillation and destruction of the microbubbles. Experimental investigations were carried out to demonstrate a doubling in contrast by imaging a scattering phantom containing an embedded silicone tube with microbubbles flowing through it. The contrast enhancement in USMOT resulting from the use of ultrasound microbubbles has been demonstrated. Destruction of the microbubbles was shown to be the dominant effect leading to contrast improvement as shown by simultaneously detecting the ultrasound and speckle contrast signals. Line scans of a microbubble filled silicone tube embedded in a scattering phantom demonstrated experimentally the significant image contrast improvement that can be achieved using microbubbles and demonstrates the potential as a future clinical imaging tool.

  16. Variational contrast enhancement guided by global and local contrast measurements for single-image defogging

    Science.gov (United States)

    Zhou, Li; Bi, Du-Yan; He, Lin-Yuan

    2015-01-01

    The visibility of images captured in foggy conditions is impaired severely by a decrease in the contrasts of objects and veiling with a characteristic gray hue, which may limit the performance of visual applications out of doors. Contrast enhancement together with color restoration is a challenging mission for conventional fog-removal methods, as the degrading effect of fog is largely dependent on scene depth information. Nowadays, people change their minds by establishing a variational framework for contrast enhancement based on a physically based analytical model, unexpectedly resulting in color distortion, dark-patch distortion, or fuzzy features of local regions. Unlike previous work, our method treats an atmospheric veil as a scattering disturbance and formulates a foggy image as an energy functional minimization to estimate direct attenuation, originating from the work of image denoising. In addition to a global contrast measurement based on a total variation norm, an additional local measurement is