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Fallahi A.,Hamedan University of Technology | Khotanlou H.,Bu - Ali Sina University | Pooyan M.,Shahed University | Hashemi H.,Advanced Diagnostic and Interventional Radiology Research Center | Oghabian M.A.,Research Center for Science and Technology in Medicine
Biomedical Engineering - Applications, Basis and Communications | Year: 2014

Uterine fibroids are common tumors of female pelvis. Uterine volume measurement before and after surgery has an important role in predicting the outcome and later on in comparing with the result of the uterine fibroid shrinkage surgery. Because of inhomogeneity and different shapes and sizes of uterus and fibroids, segmentation of uterus is a difficult task. In this paper, using T1 and Enhanced-T1 MR images uterine is initially segmented using a new clustering algorithm named neighborhood information affected possibilistic fuzzy C-means (NIAPFCM). NIAPFCM uses membership, typicality and spatial neighborhood information to cluster each voxel. Finally, the redundant parts are removed by superimposing the segmented region of the T1-enhanced image over the registered T1 image. Gaussian mixture model (GMM) is applied to the extracted region histogram as a model for accurate tresholding. The results obtained using the proposed method are evaluated by comparing with manual segmentations using volume-based and distance-based metric methods. Also, the result of NIAPFCM is compared with fuzzy C-means (FCM) and possibilistic fuzzy C-means (PFCM) algorithms. We found this algorithm efficient, which provides good and reliable results. © 2014 National Taiwan University.


Khallli M.,Tehran University of Medical Sciences | Eskandari G.,Tehran University of Medical Sciences | Ghajarzadeh M.,Tehran University of Medical Sciences | Azimi A.,Tehran University of Medical Sciences | And 6 more authors.
Current Topics in Nutraceutical Research | Year: 2012

The goal of this study was to evaluate the effects of lipoic acid on disease severity and fatigue experience in cases of multiple sclerosis. Fifty multiple sclerosis patients were randomly assigned to lipoic acid or placebo groups. Lipoic acid (1200mg/day) or placebo was administered to the two groups for three months. All subjects were asked to fill out valid and reliable Persian version of FSS (fatigue severity scale) questionnaires, were evaluated by neurologists and underwent MRI examinations before and after the study. Thirty-nine subjects participated in the study. Demographic characteristics, (EDSS) Expanded Disability Status Scale and FSS were not significantly different between the two groups at baseline. No significant differences between EDSS and FSS of the two groups after placebo or supplement applications were observed. In comparison with baseline, the EDSS scores did not decrease significantly in either group (P value =0.06 and p value =0.8). In subjects with baseline EDSS >0,EDSS showed significant decreases in the lipoic group (p value= 0.028). Comparing MRI findings with baseline, three new enhanced plaques were observed in one control case, two new enhanced plaques were observed in one supplement case and three in the placebo group had one new enhanced plaque (p=0.1). Based on the positive results of the current study future studies with larger patient populations and longer durations are needed. Copyright © 2012 by New Century Health Publishers, LLC.


Arjmand A.,Shahid Beheshti University of Medical Sciences | Arjmand A.,Advanced Diagnostic and Interventional Radiology Research Center
Iranian Red Crescent Medical Journal | Year: 2013

Context: Coronary artery disease (CAD) is the foremost cause of death in many countries and hence, its early diagnosis is usually concerned as a major healthcare priority. Coronary artery calcium scoring (CACS) using either electron beam computed tomography (EBCT) or multislice computed tomography (MSCT) has been applied for more than 20 years to provide an early CAD diagnosis in clinical routine practice. Moreover, its association with other body organs has been a matter of vast research. Evidence Acquisition: In this review article, techniques of CACS using EBCT and MSCT scanners as well as clinical and research indications of CACS are searched from PubMed, ISI Web of Science, Google Scholar and Scopus databases in a time period between late 1970s through July 2013 and following appropriate selection, dealt with. Moreover, the previous and ongoing research subjects and their results are discussed. Results: The CACS is vastly applied in early detection of CAD and in many other research fields. Conclusions: CACS has remarkably changed the screening techniques to detect CAD earlier than before and is generally accepted as a standard of reference for determination of risk of further cardiac events.


Arjmand Shabestari A.,Shahid Beheshti University of Medical Sciences | Arjmand Shabestari A.,Advanced Diagnostic and Interventional Radiology Research Center | Pourghorban R.,Shahid Beheshti University of Medical Sciences | Tehrai M.,Day General Hospital | And 4 more authors.
International Journal of Cardiovascular Imaging | Year: 2013

With advent of transcatheter aortic valve implantation, using multislice computed tomography (MSCT) to provide detailed data about aortic root has become more crucial. We compared aortic dimension changes during cardiac cycle in patients with and without aortic valve calcification and evaluated its correlation with aortic valve calcium score in former group. Fifty-two patients with and 52 subjects without aortic valve calcification underwent coronary MSCT using two 64-slice and a dual-source 256-slice CT scanners. Aortic root dimensions were measured in both systolic and diastolic phases. Changes in annular maximum diameter (Dmax), minimum diameter (Dmin), cross sectional area and perimeter, three diameters of sinuses of Valsalva (Va, Vb and Vc), sinotubular junction maximum (STJmax) and minimum (STJmin) diameters between systolic and diastolic phases (systole minus diastole) were -0.59 mm, -0.05 mm, -2.53 mm2, -1.48 mm, +0.91 mm, +1.08 mm, +0.42 mm, +0.63 mm, +0.40 mm and in those without aortic calcification -0.33 mm, 0.00 mm, -6.92 mm2, -0.41 mm, +0.30 mm, +0.38 mm, +0.61 mm, +0.33 mm, +0.20 mm in patients with aortic calcification, respectively. Apart from two diameters in sinuses of Valsalva (Va and Vb), changes in all other diameters of aortic root during cardiac cycle were not significantly different between the two groups. Furthermore, in patients with aortic calcification, no significant correlation was detected between changes in nearly all aortic root dimensions during cardiac cycle and aortic valve calcium score or location of calcification (annular, commissural or both). © 2013 Springer Science+Business Media Dordrecht.


Gity M.,Advanced Diagnostic and Interventional Radiology Research Center | Gity M.,Tehran University of Medical Sciences | Arabkheradmand A.,Tehran University of Medical Sciences | Taheri E.,Advanced Diagnostic and Interventional Radiology Research Center | And 5 more authors.
Journal of Breast Cancer | Year: 2015

Purpose: Adenosis lesions of the breast, including sclerosing adenosis and adenosis tumors, are a group of benign proliferative disorders that may mimic the features of malignancy on imaging. In this study, we aim to describe the features of breast adenosis lesions with suspicious or borderline findings on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Methods: In our database, we identified 49 pathologically proven breast adenosis lesions for which the final assessment of the breast MRI report was classified as either category 4 (n=45) or category 5 (n=4), according to the Breast Imaging Reporting and Data System (BI-RADS) published by the American College of Radiology (ACR). The lesions had a final diagnosis of either pure adenosis (n=33, 67.3%) or mixed adenosis associated with other benign pathologies (n=16, 32.7%). Results: Of the 49 adenosis lesions detected on DCE-MRI, 32 (65.3%) appeared as enhancing masses, 16 (32.7%) as nonmass enhancements, and one (2.1%) as a tiny enhancing focus. Analysis of the enhancing masses based on the ACR BI-RADS lexicon revealed that among the mass descriptors, the most common features were irregular shape in 12 (37.5%), noncircumscribed margin in 20 (62.5%), heterogeneous internal pattern in 16 (50.0%), rapid initial enhancement in 32 (100.0%), and wash-out delayed enhancement pattern in 21 (65.6%). Of the 16 nonmass enhancing lesions, the most common descriptors included focal distribution in seven (43.8%), segmental distribution in six (37.5%), clumped internal pattern in nine (56.3%), rapid initial enhancement in 16 (100.0%), and wash-out delayed enhancement pattern in eight (50.0%). Conclusion: Adenosis lesions of the breast may appear suspicious on breast MRI. Awareness of these suspicious- appearing features would be helpful in obviating unnecessary breast biopsies. © 2015, Korean Breast Cancer Society. All rights reserved.

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