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.

Introduction: This study aimed to assess the effect of controlled mouth breathing during the resting state using functional magnetic resonance imaging (fMRI). Methods: Eleven subjects participated in this experiment in which the controlled “, Nose”,and “, Mouth”,breathings of 6 s respiratory cycle were performed with a visual cue at 3T MRI. Voxel-wise seed-to-voxel maps and whole-brain region of interest (ROI)-to-ROI connectome maps were analyzed in both “, Nose>Mouth”,and “, Mouth>Nose”,contrasts. Results: As a result, there were more connection pairs in the “, Mouth”,breathing condition, i. e., 14 seeds and 14 connecting pairs in the “, Mouth>Nose”,contrast, compared to 7 seeds and 4 connecting pairs in the “, Nose>Mouth”,contrast (false discovery rate [FDR] of P<0. 05). Conclusion: The present study demonstrated that mouth breathing with controlled respiratory cycles could significantly induce alterations in functional connectivity in the resting-state network, suggesting that it can differently affect resting brain function,in particular, the brain can hardly rest during mouth breathing, as opposed to conventional nasal breathing.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by death of motor neurons leading to devastating muscle weakness and wasting and weight loss. It causes mixed picture of Lower Motor Neuron (LMN) and Upper Motor Neuron (UMN) dysfunction. The wide spectrums of atypical presentations can frequently lead to expensive work-up and undue delay in diagnosis of ALS. Occasionally, brain MRI of ALS patients shows some lesions in white matter. Moreover, Cerebrospinal Fluid (CSF) analysis demonstrates Oligoclonal Bands (OCB) in a few subjects. Because of the UMN signs, brain white matter lesions and presence of OCBs in CSF, ALS can be misdiagnosed as Multiple Sclerosis (MS). Also, some findings in ALS mimic Central Nervous System (CNS) vasculitis. We are reporting a case of ALS in a 48-year-old man presenting with subacute progressive spastic diparesis and brain white matter lesions which was initially misdiagnosed by MS and CNS vasculopathy.

Background: Multiple sclerosis (MS) is the most prevalent inflammatory demyelinating disease that involves central nervous system. Cognitive disorders are common complaint of patients with MS. Hippocampus is a part of brain that plays significant role in cognition, and is highly sensitive to inflammatory changes induced by MS. This study was the first study conducted to assess hippocampal angle in cognitive disorders occur in patients with MS. Methods: This was a prospective cross-sectional study conducted on 39 patients with MS referred to university hospitals in Isfahan City, Iran, during 2015-17. Patients were divided to two groups of with cognitive and without cognitive disorders based on Multiple Sclerosis Neuropsychology Questionnaire (MSNQ). Patients' age, gender, and Expanded Disability Status Score (EDSS) were evaluated. Then, all patients underwent magnetic resonance imaging (MRI) and hippocampal angle, bifrontal diameter (BFD), and third ventricle width (3VW) was measured based on their imaging. Findings: Cognitive dysfunction was significantly in association with patients age (P = 0. 013; B =-0. 164) and EDSS (P = 0. 005; B = 1. 23). No association was found between cognitive impairment and hippocampal angle (P = 0. 270), and EDSS was not significantly correlated with hippocampal angle as well (P = 0. 500, r = 0. 317). In addition, BFD and 3VW were not statistically in correlation with cognitive impairment (P > 0. 050). Conclusion: Based on findings of our study, there was no association between hippocampal angle and neurocognitive function of patients with MS. In addition, this angle was not affected by patients' age and gender as well. Further studies with larger sample populations and consideration of drug regimen and duration of disease are recommended.

Introduction As functional magnetic resonance imaging (fMRI) is too expensive and time consuming, its frequent implementation is difficult. The aim of this study is to evaluate repeatability of detecting visual cortex activity in fMRI.Materials and Methods In this study, 15 normal volunteers (10 female, 5 male; Mean age±SD: 24.7±3.8 years) attended. functional magnetic resonance images were obtained during a visual task of sine-wave with spatial frequency of 1.84 cpd and temporal frequency of 8 Hz in three scan runs. Two runs of functional images were provided consecutively in a session, and the third run was provided 1-6 weeks later. The activation map was created using the data obtained from the block-designed fMRI study. Voxels whose Z value was above a threshold of 2.3, at a significance level p=0.05, were considered activated. After image processing, the blood oxygen level dependent (BOLD) signal changes and the number of activated voxels in response to visual stimuli were compared in different runs.Results The results of this study demonstrate no significant difference between the number of activated voxels and BOLD signal in first and second runs in one session (Paired t-test, p>0.05). Moreover, there is a considerable correlation between first and second scan runs (rsignal=0.74, p=0.006 and rvoxel=0.62, p=0.03), while the correlation between the runs in separate sessions is weak (rsignal=0.28, p=0.38 and rvoxel=0.32, p=0.31).Conclusion Since the repeatability of BOLD signal and number of activated voxels in one session is considerably better than that in the separate sessions, it is suggested that in fMRI visual studies that need repeated scanning, scans should be acquired during a single session.