Background: Magnetic resonance imaging (MRI) of the wrist joint is a useful method in the diagnosis of triangular fibrocartilage complex (TFCC), ligaments and tendons, peripheral nerves, cartilage and carpal tunnel syndrome. However, the evaluation of these small anatomical structures is a topic of investigation. In some instances, the diagnostic indices of MRI in tears and other lesions of cartilage and ligamentous structures are relatively low, so the protocols should be optimized. Objectives: In this study, we aim to compare new MRI protocols of 3D T2SPACE, PD BLADE and T2 BLADE with the conventional protocols, including T2 FSE, PD FSE, and T1 FSE in case of signal intensity. Patients and Methods: Twenty patients with a history of wrist trauma or suspected wrist lesions were referred by orthopedic hand surgeons and enrolled into the study. All the protocols were carried out on all patients and the images were assessed quantitatively by measurement of signal to noise ratio (SNR) and contrast to noise ratio (CNR). Then, these parameters were compared between different protocols. SPSS ver.18 was used for the statistical analyses. Results: SNR of the cartilage, TFCC on 3D T2SPACE and T1 FSE was better than other sequences (P < 0.001). SNR of the bone on PD BLADE was significantly higher (P < 0.001) than that of conventional protocols. PD BLADE images showed significantly higher bonecartilage CNR and bone-TFCC CNR (P < 0.001 to P < 0.001). CNR of cartilage-TFCC on T1 FSE was better than other sequences, but no significant statistical differences were seen. Conclusion: High-resolution MR images of the wrist using 3D T2SPACE, PD BLADE and T2 BLADE were superior to those using conventional sequences quantitatively. High-SNR and CNR MR imaging with SPACE and BLADE would be a promising method to diagnose wrist lesions.

Background: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system that causes demyelination or loss of myelin in the white and gray matter of the brain and spinal cord. Objectives: In the current study, the phase sensitive inversion recovery (PSIR) sequence was compared with the other sequences (T2-weighted (T2W), short tau inversion recovery (STIR)) to represent the number and conspicuity of the lesions. Patients and Methods: In this study, 35 MS patients were referred to the imaging center for MRI of the cervical spine. In the sagittal view, T2 weighted turbo spin echo (T2TSE), STIR, and PSIR and in the axial view, T2 TSE, and PSIR sequences were compared. The sequences were compared regarding the number of lesions and conspicuity. P value < 0.05 was considered statistically significant. Results: In sagittal view MRIs, mean plaque number in T2TSE, STIR and PSIR were 1.7 ± 1.1, 3.5 ± 1.4, and 3.4 ± 1.4, respectively (P < 0.001; PSIR and STIR were greater than T2TSE but their difference was not statistically significant). Regarding comparison of imaging conspicuity, most of the plaques in PSIR showed good resolution (75%). In fact, the highest conspicuity of plaques was detected in PSIR (P < 0.001). In axial view MRIs, comparing mean plaque count and conspicuity of lesions, PSIR showed better results than T2TSE (P < 0.001). Conclusion: PSIR sequence showed high sensitivity and precision in the detection of plaques in the cervical spine. PSIR sequence is efficient as a complementary sequence in evaluating the cervical lesions of MS patients. It could increase the diagnostic accuracy in these patients.

Objective: The use of an appropriate contrast agent performs a major role in brain magnetic resonance imaging (MRI) of multiple sclerosis (MS) patients. The present study aimed to make a comparison between the diagnostic values of Gadovist and Magnevist considering the successive imaging times in contrast-enhanced brain MRI of MS patients. Materials and Methods: A total of 62 relapsing-remitting MS patients (56 females, mean age of 31 years) were enrolled in the present study. All of them underwent two sessions of standard contrast-enhanced brain MRI upon enrollment and 48 h later. The participants were randomly assigned to each contrast agent. T1-weighted (T1W) images were taken 30 sec, as well as 5, 10, 15, and 30 min after the contrast injection. For all of the images, two neuro-radiologists who were blinded to the contrast type counted the number of plaques in the brain. In addition, for the enhanced plaques larger than 10 mm, the signal intensity (SI) was determined using its region of interest. Results: The mean plaque number significantly increased from 30 sec to 15 min for both contrasts separately (P<0.001). Nonetheless, the slight increases in the mean plaque number from 15-30 min for both Gadovist and Magnevist were not statistically significant (both P-Values>0.25). The mean plaque number in the Gadovist group was higher, compared to that in the Magnevist group at both 15 and 30 min, and the differences were statistically on the borderline (both P-Values=0.07). The mean SI of enhanced plaques gradually increased in the course of imaging in both contrast groups. Except for 30 sec, in all other time sessions, the mean SI was higher in Gadovist-enhanced MR images, compared to Magnevist-enhanced MR images (P<0.01). Conclusion: As evidenced by the obtained results, Gadovist showed a relatively better diagnostic value for brain MRI of MS patients. Furthermore, the findings suggested that it is cost-effective to take MRI only up to 15 min (instead of 30 min) after contrast injection in both agents.

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 relapsingremitting 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 Â 12 Â 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 ¼ .04). The mean concentration of Cr and mIns (P ¼ .04) and the relative metabolic concentration (dentate nucleus/pons) of lipid 1.3/Cr (P ¼ .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 ¼ .02), lactate/Cr (P ¼ .04), and Cr (dentate nucleus/pons) (P ¼ .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.

Background: Precise detection and classification of intracortical (IC) lesions in multiple sclerosis (MS) patients are very important for understanding their role in disease progression and determining their effects on the clinical presentations of the disease. Objectives: This study aimed to evaluate the efficacy of phase-sensitive inversion recovery (PSIR) in delineation of cortical lesions in MS patients. Patients and Methods: This cross-sectional, single-center study was performed among 38 patients with the mean age of 31 years, who were recruited from December 2018 to August 2020. All MS patients underwent magnetic resonance imaging (MRI), using a 1.5-Tesla scanner. Two expert neuroradiologists interpreted the fluid-attenuated inversion recovery (FLAIR), T2-weighted turbo spin echo (T2W-TSE), and PSIR images. The lesions were classified as purely IC, mixed gray/white matter (WM) [leukocortical (LC)], and juxtacortical (JC). The number of lesions in each region was compared between the FLAIR, T2W-TSE, and PSIR sequences. Results: The number of cortical lesions (IC and LC) was significantly higher in PSIR compared to T2W-TSE and Fluid attenuated inversion recovery (FLAIR) (P < 0.001), while the number of JC lesions was lower; in other words, the mean number of plaques was higher in T2W-TSE and FLAIR as compared to PSIR. Conclusion: The PSIR sequence significantly improved the delineation of cortical lesions and could be useful in monitoring cortical injuries and disease progression in MS patients.