Does Gadolinium Deposition Lead to Metabolite Alteration in the Dentate Nucleus? An MRS Study in Patients with MS.

BACKGROUND AND PURPOSE: Repeat contrast-enhanced MR imaging exposes patients with relapsing-remitting MS to frequent administration of gadolinium-based contrast agents. We aimed to investigate the potential metabolite and neurochemical alterations of visible gadolinium deposition on unenhanced T1WI in the dentate nucleus using MRS. MATERIALS AND METHODS: This prospective study was conducted in a referral university hospital from January 2020 to July 2021. The inclusion criteria for case and control groups were as follows: 1) case: patients with relapsing-remitting MS, visible gadolinium deposition in the dentate nucleus (ribbon sign), >5 contrast-enhanced MR images obtained; 2) control 1: patients with relapsing-remitting MS without visible gadolinium deposition in the dentate nucleus, >5 contrast-enhanced MR images obtained; 3) control 2: patients with relapsing-remitting MS without visible gadolinium deposition in the dentate nucleus, <5 contrast-enhanced-MR images obtained; and 4) control 3: adult healthy individuals, with no contrast-enhanced MR imaging. Dentate nucleus and pontine single-voxel 12 × 12 × 12 MRS were analyzed using short TEs. RESULTS: Forty participants (10 per group; 27 [67.5%] female; mean age, 35.6 [SD, 9.6] years) were enrolled. We did not detect any significant alteration in the levels of NAA and choline between the studied groups. The mean concentrations of mIns were 2.7 (SD, 0.73) (case), 1.5 (SD, 0.8) (control 1), 2.4 (SD, 1.2) (control 2), and 1.7 (SD, 1.2) (control 3) (P = .04). The mean concentration of Cr and mIns (P = .04) and the relative metabolic concentration (dentate nucleus/pons) of lipid 1.3/Cr (P = .04) were significantly higher in the case-group than in healthy individuals (controls 1-3). Further analyses compared the case group with cumulative control 1 and 2 groups and showed a significant increase in lactate (P = .02), lactate/Cr (P = .04), and Cr (dentate nucleus/pons) (P = .03) in the case group. CONCLUSIONS: Although elevated concentrations of Cr, lactate, mIns, and lipid in the dentate nucleus of the case group indicate a metabolic disturbance, NAA and choline levels were normal, implying no definite neuronal damage.

Diagnosis of Tempromandibular Disorders Using Local Binary Patterns.

BACKGROUND: Temporomandibular joint disorder (TMD) might be manifested as structural changes in bone through modification, adaptation or direct destruction. We propose to use Local Binary Pattern (LBP) characteristics and histogram-oriented gradients on the recorded images as a diagnostic tool in TMD assessment. MATERIAL AND METHODS: CBCT images of 66 patients (132 joints) with TMD and 66 normal cases (132 joints) were collected and 2 coronal cut prepared from each condyle, although images were limited to head of mandibular condyle. In order to extract features of images, first we use LBP and then histogram of oriented gradients. To reduce dimensionality, the linear algebra Singular Value Decomposition (SVD) is applied to the feature vectors matrix of all images. For evaluation, we used K nearest neighbor (K-NN), Support Vector Machine, Naïve Bayesian and Random Forest classifiers. We used Receiver Operating Characteristic (ROC) to evaluate the hypothesis. RESULTS: K nearest neighbor classifier achieves a very good accuracy (0.9242), moreover, it has desirable sensitivity (0.9470) and specificity (0.9015) results, when other classifiers have lower accuracy, sensitivity and specificity. CONCLUSION: We proposed a fully automatic approach to detect TMD using image processing techniques based on local binary patterns and feature extraction. K-NN has been the best classifier for our experiments in detecting patients from healthy individuals, by 92.42% accuracy, 94.70% sensitivity and 90.15% specificity. The proposed method can help automatically diagnose TMD at its initial stages.

Vitamin D receptor gene polymorphisms in Iranian Azary patients with Behçet's disease.

OBJECTIVES: The aim of our study was to investigate the association of four polymorphisms of the VDR gene (FokI, BsmI, TaqI, and ApaI) with their susceptibility to Behçet's disease (BD) and their clinical manifestations with respect to the Iranian Azari population. METHOD: In this cross-sectional study we considered the BsmI, FokI, ApaI, and TaqI polymorphisms in 50 Iranian Azary patients with BD and 50 healthy controls, with the use of polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). RESULTS: A significant difference was found for the FokI polymorphism between the case and control groups. The f allele frequency of 26% was present in BD patients, compared to only 13% in the control group. In addition, the f/f genotype was significantly associated with BD. We found no significant differences between the BD and control groups regarding the distribution of ApaI, BsmI, and TaqI genotype frequencies. We found no association between VDR polymorphisms and the clinical manifestations of BD. CONCLUSIONS: The VDR f allele and f/f genotype are associated with BD in the Iranian Azari population.

Common MEFV mutations in Iranian Azeri Turkish patients with Behçet's disease.

OBJECTIVE: Behçet's disease (BD) is an inflammatory disorder of unknown cause with higher prevalence along the ancient Silk Road. BD shares epidemiological and clinical features with familial Mediterranean fever (FMF). Moreover, association of BD and certain MEFV gene mutations has been described in recent decades. We studied the role of MEFV mutations in Iranian Azeri Turkish patients with BD. METHODS: Fifty-three BD patients who met the International Study Group criteria for BD were analysed for five common MEFV mutations (M694V, V726A, M680I, M694I, and E148Q) using amplification refractory mutation system and polymerase chain reaction (PCR) restriction-digestion testing methods. A cohort of 200 healthy Azeri Turkish individuals who had been previously genotyped regarding the five common MEFV mutations served as the control group. RESULTS: Eighteen patients were found to carry a single MEFV mutation and one additional patient was compound heterozygote. There was a statistically significant difference between the patient group and ethnically matched healthy individuals regarding M694V and M680I mutations (p = 0.01 and p = 0.04, respectively). Both BD groups (carriers and non-carriers of MEFV mutations) were similar in their clinical symptoms. CONCLUSION: Definite MEFV mutations seem to be a susceptibility factor for BD in our cohort of Iranian Azeri Turkish patients.