Gadolinium effect on thalamus and whole brain tissue segmentation.

PURPOSE: Gadolinium-based contrast agent (GBCA) effect on automated segmentation algorithms of subcortical gray matter (GM) is not fully known. The aim of this study is to determine gadolinium effect on the segmentation of the thalamus and whole brain tissue using different automated segmentation techniques. METHODS: Eighty-four multiple sclerosis (MS) patients underwent an MRI acquisition of two 3DT1-weighted sequences with and without gadolinium injection among which 10 were excluded after image quality check. Manual thalamic segmentation considered as gold standard was performed on unenhanced T1 images. volBrain and FSL-Anat were used to automatically segment the thalamus on both enhanced and unenhanced T1 and the degree of similitude (DICE) values were compared between manual and automatic segmentations. Whole brain tissue segmentation (GM, white matter (WM), and lateral ventricles (LV)) was also performed using SIENAX. A paired samples t test was applied to test the significance of DICE value differences between the thalamic manual and automatic segmentations of both enhanced and unenhanced T1 images. RESULTS: Significant differences (FSL-Anat 1.474% p < 0.001 and volBrain 1.990% p < 0.001) in DICE between thalamic manual and automatic segmentations on both enhanced and unenhanced images were observed. Automatic tissue segmentation showed a mean DICE of 81.5%, with LV having the lowest DICE value (74.2%). When compared to tissue segmentations, automatic thalamic segmentations by FSL-Anat or volBrain demonstrated a higher degree of similitude (FSL-Anat = 91.7% and volBrain = 90.7%). CONCLUSION: Gadolinium has a significant effect on subcortical GM segmentation. Although significant, the observed subtle changes could be considered acceptable when used for region-based analysis in perfusion or diffusion imaging.

Use of retinal optical coherence tomography to differentiate suspected neuromyelitis optica spectrum disorder from multiple sclerosis: A cross-sectional study.

BACKGROUND: Retinal optical coherence tomography (OCT) can differentiate definite NMOSD (dNMOSD) from multiple sclerosis (MS), but has not been evaluated in patients with a high clinical suspicion of NMOSD and not fulfilling the current consensus diagnostic criteria, referred in this paper as "potential" NMOSD (pNMOSD). AIM: To compare the retinal OCT measurements between patients with pNMOSD, dNMOSD, MS, and reference healthy controls (HC). MATERIAL AND METHODS: In this cross-sectional study, clinical and demographic characteristics, as well as OCT measurements of peripapillary retinal nerve fiber layer (pRNFL), inner nuclear layer (INL), macular retinal nerve fiber layer (mRNFL), outer nuclear layer (ONL) ganglion cell/inner plexiform layer (GCIPL), and macular volume (MV) were compared between groups. Mixed-effects regression models adjusting for within-patient inter-eye correlations, controlling for age, gender, disease duration and history of optic neuritis per eye were explored. Subgroup analyses were performed on eyes with previous optic neuritis. RESULTS: 234 eyes (20 pNMOSD, 33 dNMOSD, 138 MS, and 43 HC) were included. Controlling for age, gender, disease duration, and history of optic neuritis per eye, pNMOSD eyes showed decreased GCIPL, pRNFL, mRNFL and MV thicknesses, similar to eyes with dNMOSD, but significantly thinner than MS and HC subjects' eyes. Similar results were obtained for the pRNFL, mRNFL, GCIPL, INL and MV thickness in the subgroup analysis exploring only eyes with history of optic neuritis (12 pNMOSD, 15 dNMOSD, and 27 MS). CONCLUSION: Retinal OCT measurements in patients with pNMOSD were similar to dNMOSD, but significantly lower than patients with MS and healthy controls. This suggests that retinal OCT measures could be helpful markers supportive of NMOSD diagnosis and should be explored in larger studies as a valuable addition to the current consensus diagnostic criteria.

Gadoterate Meglumine Administration in Multiple Sclerosis has no Effect on the Dentate Nucleus and the Globus Pallidus Signal Intensities.

RATIONALE AND OBJECTIVES: Previous studies on possible accumulation of gadolinium-based contrast agents (GBCA) in the brain suggest that macrocyclic GBCA are less likely to accumulate than linear GBCA. However, conflicting results have been reported, especially in MS. The aim of this study is to investigate retrospectively the correlation between gadoterate-meglumine (macrocyclic GBCA) use and T1 signal intensity changes (SI) in the dentate nucleus and the GP on unenhanced T1-weighted images in a large cohort of MS patients. MATERIALS AND METHODS: Unenhanced T1-weighted images of 232 MS patients who previously received multiple intravenous administrations of 0.1 mmol/kg of gadoterate-meglumine were reviewed. The change in T1 SI ratios of dentate nucleus/central pons (DN/CP) and globus pallidus/centrum semiovale (GP/CSO) was calculated between the first and last MRIs and correlated with age, number of injections, time interval between MRIs, disease duration, activity, and therapy. RESULTS: DN/CP ratio showed no significant changes whereas the GP/CSO ratio showed a significant decrease (p < 0.0001) between the first and last MRIs. Multivariable analyses of both ratios, controlling for age, disease duration, and time interval between MRIs, showed no significant correlation between the number of gadolinium injections and the differences in DN/CP (standardized beta = -0.018, p = 0.811) or GP/CSO SI ratios (standardized beta = -0.049, p = 0.499). CONCLUSION: Repeated administration of gadoterate-meglumine in MS patients did not result in increased T1 SI in the DN or the GP. The significant decrease of GP/CSO ratio between the first and last MRIs is not due to gadolinium accumulation but rather to varying MR parameters.

The Bayesian risk estimate at onset (BREMSO) correlates with cognitive and physical disability in patients with early multiple sclerosis.

BACKGROUND: Prevention of long-term disability is the goal of therapeutic intervention in Relapsing Remitting MS (RRMS). The Bayesian Risk Estimate for MS at Onset (BREMSO) gives an individual risk score predicting disease evolution into Secondary Progressive MS (SPMS). We investigated whether BREMSO correlates with physical disability, cognitive dysfunction, and regional brain atrophy early in MS. METHODS: One hundred RRMS patients with at least two years of follow-up were enrolled. BREMSO score as well as Symbol Digit Modalities Test (SDMT) and Multiple Sclerosis Severity Score (MSSS), Timed 25-Foot Walk Test (T25-FW) and 9-Hole Peg Test (9-HPT), were assessed. Intracranial volume (ICV), subcortical gray matter structures and corpus callosum (CC) were automatically segmented on MRI images and their volumes measured. RESULTS: BREMSO score correlated negatively with SDMT at visit1 (ß = -0.33, p = 0.019), visit2 (ß = -0.34, p = 0.017) and visit3 (ß = -0.34, p = 0.014), and positively with MSSS at visit1 (r = 0.38, p = 0.006), visit2 (r = 0.47, p < 0.0001) and visit3 (r = 0.42, p = 0.002), but not with T25-FW and 9-HPT. BREMSO negatively correlated with CC volume at baseline (p < 0.03). No correlations were found with ICV and subcortical gray matter. CONCLUSIONS: BREMSO score at onset correlated with physical disability (MSSS), cognitive function (SDMT) and CC volume measurements in patients with early MS.

Effect of Vitamin D Replacement on Cognition in Multiple Sclerosis Patients.

Multiple Sclerosis is associated with deficient serum 25 hydroxyvitamin D (25 (OH)D) level and cognitive impairment. The aim of this study is to evaluate cognitive performance in MS patients with deficient 25 (OH)D (<25 ng/ml) compared to patients with sufficient levels (>35 ng/ml), then to evaluate the change in cognitive performance after 3 months of vitamin D3 oral replacement. Eighty-eight MS patients with relapsing remitting and clinically isolated type of MS, older than 18 years treated with interferon beta were enrolled. Cognitive testing was performed at baseline and at 3 months using the Montreal Cognitive Assessment (MoCA), Stroop, Symbol Digit Modalities (SDMT) and Brief Visuospatial Memory Test (BVMT-R). Serum 25 (OH)D was measured at baseline and at the end of the study. Vitamin D3 replacement improved the MS patients' cognitive performance after 3 months on the MoCA and BVMT-Delayed Recall (DR). Sufficient serum 25 (OH)D level predicted better cognitive performance on the BVMT-DR at baseline (ß: 1.74, p: <0.008) and 3 months (ß: 1.93, p: <0.01) after adjusting for all measured confounding variables. Vitamin D3 replacement could improve cognitive performance in MS patients and make a significant difference in the patient's quality of life.