Background and Aims: Disc displacement is the most common temporomandibular joint disorder and magnetic resonance imaging (MRI) is the gold standard in its diagnosis. This disorder can lead to changes in signal intensity of magnetic resonance (MR). The purpose of this study was evaluation of correlation between relative signal intensity of MR images of retrodiscal tissue, superior and inferior head of lateral ptrygoid muscle with type of anterior disk displacement and condylar head flattening in patients with temporomandibular disorder (TMD).Materials and Methods: In this retrospective study, 31 MR images of patients who had anterior disc displacement were evaluated. After relative signal intensity measurement for retrodiscal tissue, superior and inferior head of lateral ptrygoid muscle, the correlation between relative signal intensity and type of anterior disc displacement was evaluated with repeated measure ANOVA test. In each of these 3 areas, t-test was used to compare the groups with and without condylar head flattening.Results: The correlation between relative signal intensity of MR images and type of anterior disc displacement in retrodiscal tissue, superior and inferior head of lateral ptrygoid muscle was not significant. There was also no statistically significant correlation between relative signal intensity of MR images and flattening of condylar head in retrodiscal tissue, superior and inferior head of lateral ptrygoid muscle (P>0.05).Conclusion: According to findings of this study, relative signal intensity of MR images in retrodiscal tissue, superior and inferior head of ptrygoid muscle is not a good predictor for type of anterior disc displacement and flattening of condylar head. It seems that this cannot be used as a diagnostic marker for TMD progression.

Background: Prostate cancer is the third leading cause of death and is the most common cause of cancer in elderly men. Regarding to the low accuracy of screening methods such as prostate-specific antigen (PSA), Digital Rectal Examination (DRE) and trans rectal ultrasound (TRUS) in detection and localization of tumor, Magnetic Resonance Imaging (MRI) and Diffusion Weighted Imaging (DWI) attracted many attentions in the past years. DWI reveals micro-molecular diffusion, which is the Brownian motion of the spins in biologic tissues. This technique can delineate pathologic lesions with high tissue contrast against generally suppressed background signal. In this paper, the value of DWI in detection of prostate cancer is studied.Methods: In this cross-sectional study, the studied population are suspicious patients to prostate cancer based on high Prostatic Specific Antigen level or abnormal Digital Rectal Examination who refered for prostate biopsy to radiology department of Hazrate- Rasoul Hospital during the year 2011. The results of DWI are compared to biopsy results for all patients.Results: Eighty five patients are selected. The DWI sensitivity in detecting of prostate cancer is 100%, specificity 97.1% and positive and negative predictive values are 89.5% and 100%, respectively. The results showed that if DWI reports the prostate cancer as negative, the result was highly reliable and if it reports as positive, although the report was not 100% reliable, but it still had high reliability, more than 90%.Conclusion: DWI had high accuracy in detecting prostate cancer for patients with cancer. Also the accuracy of this method for patients without prostate cancer was acceptable compared to the other common methods.

Cerebral Palsy is the most common chronic motor disorder of childhood, that affecting approximately 3 infants per 1000 live-births. The risk of brain injuries that potentially cause Cerebral Palsy has amplified with increasing in survival rates for preterm infants. In addition Cerebral Palsy has a huge economic impact, to immeasurable health, social, and psychological problems that affected children and their families suffer. Cerebral Palsy, among 18 common congenital disorders, has the highest lifetime costs per new case. Thus, efforts to prevent its occurrence, minimize the morbidity, and improve the patient outcomes are important at both the individual and societal levels. In each trimester, different patterns of brain damage or abnormal insults can represent times and etiology of injuries. Knowledge of the etiology and pathogenesis of abnormal brain growth during antenatal, perinatal and neonatal damages can be helping us for prevention. Also Magnetic Resonance Imaging (MRI) studies of subjects with multiple forms of cerebral palsy reported significantly more overall abnormalities, malformations, and white matter damage but in this review study we discuss in what extent MRI is useful in detecting cerebral palsy pathogenesis.

Background: Prostate cancer is the second most common cancer among men in the world. Due to the slow growth of this cancer, its early detection can lead to definitive treatment and mortality reduction. Based on the lower diagnostic ability of conventional methods, imaging methods have been paid attention in recent years. Objectives: The aim of this study was to evaluate the value and accuracy of diffusion MRI in the prostate cancer as a diagnostic method. Methods: This was a descriptive cross-sectional study conducted in a 15-month period in patients with prostate cancer who had lower urinary tract symptoms, high PSA (higher than 4 ng/mL), or an abnormal finding in the digital rectum examination. The patients were evaluated by MRI of the whole prostate gland with T2 weighted and diffusion images. Patients’ conditions were determined by a urologist with standard 12-fold transrectal sonography-guided biopsy of the prostate. Then, by a histologic examination, healthy or cancerous tissues, Gleason score, andthe positive blindnumberswere determined by a pathologist. In the end, the results were compared. Results: We observed 80 patients among whom, 25 cases (31. 2%) had malignancies in DW-MRI, including 22 cases that had a malignancy in biopsy and three cases whose biopsy indicated the benign pathology. MRI findings in 55 cases (68. 7%) were benign (BPH, prostatitis) that in four cases, malignancy was seen in the biopsy. The sensitivity of DW-MRI was 84% and specificity was 94%, indicating a high diagnostic capability for DW-MRI. The positive and negative predictive values of DW-MRI for prostate cancer were 88% and 92%, respectively. We also observed that older age leads to the lower sensitivity of the MRI. Gleason score, PSA level, and tumor burden had a direct relationship with the accuracy of DW-MRI. However, prostate volume did not have a significant relationship with the detection of cancer in MRI. Conclusions: DW-MRI can be used for better diagnosis and staging of prostate cancer in patients with prostate lesions. Accordingly, it can upgrade cancer diagnosis in patients with negative biopsies and high suspicion of cancer.

Background and Objectives: The desired segmentation of medical images is a pivotal problem in medical image processing. Segmenting the Left Ventricle (LV) in Magnetic Resonance Images (MRIs) is essential for evaluation of cardiac function. For the segmentation of cardiac MRI several methods have been proposed and implemented. The aim of this paper was to use the segmentation of LV chamber with more accuracy and comparing the results with current methods.Materials and Methods: A modified region-based active contour model was applied. A new semi-automatic algorithm suggested calculating the appropriate Balloon force according to mean intensity of the region of interest for each image. The database is included of 2,039 MR images collected from 18 children under 18. The results were compared with previous literatures according to two standards: Dice Metric (DM) and Point to Curve (P2C) to get error values.Results: According to defined standards, the obtained segmentation results are better than previously reported values in several literatures. In this study different points were used in cardiac cycle and several slices levels and classified into three levels: Base, Mid. and Apex. The better results were obtained at End Diastole (ED) in comparison with End Systole (ES), and on base slice than other slices, because of LV bigger size in ED phase and base slice.Conclusions: With segmentation of LV MRI based on novel active contour and application of the suggested algorithm for balloon force calculation, the mean improvement of DM is 19.6% in ED and 49.5% in ES phase. Also the mean improvement of P2C for ED and ES phase is 43.8% and 39.6% respectively.