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Background: Decreased motion perception has been suggested as a marker for visual pathway demyelination in optic neuritis (ON) and/or multiple sclerosis (MS). Objectives: To examine the influence of neuro-axonal damage on motion perception in MS and neuromyelitis optica spectrum disorders (NMOSD). Methods: We analysed motion perception with numbers-from-motion (NFM), visual acuity, (multifocal (mf)) VEP, optical coherence tomography in patients with MS (n = 38, confirmatory cohort n = 43), NMOSD (n = 13) and healthy controls (n = 33). Results: NFM was lower compared with controls in MS (B = −12.37, p < 0.001) and NMOSD (B = −34.5, p < 0.001). NFM was lower in ON than in non-ON eyes (B = −30.95, p = 0.041) in NMOSD, but not MS. In MS and NMOSD, lower NFM was associated with worse visual acuity (B = −139.4, p < 0.001/ B = −77.2, p < 0.001) and low contrast letter acuity (B = 0.99, p = 0.002/ B = 1.6, p < 0.001), thinner peripapillary retinal nerve fibre layer (B = 1.0, p < 0.001/ B = 0.92, p = 0.016) and ganglion cell/inner plexiform layer (B = 64.8, p < 0.001/ B = 79.5, p = 0.006), but not with VEP P100 latencies. In the confirmatory MS cohort, lower NFM was associated with thinner retinal nerve fibre layer (B = 1.351, p < 0.001) and increased mfVEP P100 latencies (B = −1.159, p < 0.001). Conclusions: Structural neuro-axonal visual pathway damage is an important driver of motion perception impairment in MS and NMOSD. [ABSTRACT FROM AUTHOR]

Background: Spinal cord (SC) affection is a hallmark symptom of neuromyelitis optica spectrum disorders (NMOSD). Patients with aquaporin-4 (AQP4-IgG+) or myelin oligodendrocyte glycoprotein (MOG-IgG+) antibody seropositivity show this overlapping clinical phenotype. Objective: Quantitative comparison of SC lesions and atrophy in AQP4-IgG+ and MOG-IgG+ NMOSD. Methods: AQP4-IgG+ (n = 38), MOG-IgG+ (n = 15) NMOSD patients and healthy controls (HC, n = 24) were analysed for SC lesion (prevalence, length, location), atrophy as mean upper cervical cord area (MUCCA), Expanded Disability Status Scale (EDSS), timed 25-foot walk speed (T25FWS) and 9-hole peg test (9HPT) measures. Results: In total, 92% (35/38) of AQP4-IgG+ and 53% (8/15) of MOG-IgG+ patients had myelitis attacks (χ2 = 6.47, p = 0.011). 65.8%/26.7% of AQP4-/MOG-IgG+ patients had chronic SC lesions (χ2 = 5.16, p = 0.023), with similar proportions in cervical, upper thoracic and lower thoracic cord, and no length differences. MUCCA was decreased in AQP4-IgG+ (t = –2.27, p = 0.028), but not MOG-IgG+ patients (t = 0.58, p = 0.57) compared to HC. MUCCA associated with myelitis attacks (rho = –0.33, p = 0.016), EDSS (rho = –0.31, p = 0.030), pyramidal functional score (rho = –0.42, p = 0.003), T25FWS (r = 0.43, p = 0.010) and 9HPT Z-score (r = 0.32, p = 0.037), regardless of antibody status. Conclusion: AQP4-IgG+ patients had more myelitis attacks, SC lesions and SC atrophy was more pronounced than in MOG-IgG+ patients. MUCCA is associated with clinical myelitis attacks and disability in all NMOSD patients. [ABSTRACT FROM AUTHOR]

Objective: Since recent studies suggested a role of the striatum and prefrontal cortex for multiple sclerosis (MS)-related fatigue, we investigated resting-state functional connectivity alterations of striatal subdivisions and the dorsolateral prefrontal cortex (dlPFC). Methods: Resting-state functional magnetic resonance imaging was acquired in 77 relapsing–remitting MS patients (38 fatigued (F-MS), 39 non-fatigued (NF-MS)) and 41 matched healthy controls (HC). Fatigue severity was assessed using the fatigue severity scale. Seed-based connectivity analyses were performed using subregions of the striatum and the dlPFC as regions of interest applying non-parametric permutation testing. Results: Compared to HC and NF-MS patients, F-MS patients showed reduced caudate nucleus and ventral striatum functional connectivity with the sensorimotor cortex (SMC) and frontal, parietal, and temporal cortex regions. Fatigue severity correlated negatively with functional connectivity of the caudate nucleus and ventral striatum with the SMC and positively with functional connectivity of the dlPFC with the rostral inferior parietal gyrus and SMC. Conclusion: MS-related fatigue is associated with reduced functional connectivity between the striatum and sensorimotor as well as attention and reward networks, in which the ventral striatum might be a key integration hub. Together with increased connectivity between the dlPFC and sensory cortical areas, these connectivity alterations shed light on the mechanisms of MS-related fatigue. [ABSTRACT FROM AUTHOR]

Background: Decision-making (DM) abilities deteriorate with multiple sclerosis (MS) disease progression which impairs everyday life and is thus clinically important. Objective: To investigate the underlying neurocognitive processes and their relation to regional gray matter (GM) loss induced by MS. Methods: We used a functional magnetic resonance imaging (fMRI) Iowa Gambling Task to measure DM-related brain activity in 36 MS patients and 21 healthy controls (HC). From this activity, we determined neural parameters of two cognitive stages, a deliberation ("choice") period preceding a choice and a post-choice ("feedback") stage reporting decision outcomes. These measures were related to DM separately in intact and damaged GM areas as determined by a voxel-based morphometry analysis. Results: Severely affected patients (with high lesion burden) showed worse DM-learning than HC (t = -1.75, p = 0.045), moderately affected (low lesion burden) did not. Activity in the choice stage in intact insular (t = 4.60, pFamily-Wise Error [FWE] corrected = 0.034), anterior cingulate (t = 4.50, pFWE = 0.044), and dorsolateral prefrontal areas (t = 4.43, pFWE = 0.049) and in insular areas with GM loss (t = 3.78, pFWE = 0.011) was positively linked to DM performance across patients with severe tissue damage and HC. Furthermore, activity in intact orbitofrontal areas was positively linked to DM-learning during the feedback stage across these participants (t = 4.49, pFWE = 0.032). During none of the stages, moderately affected patients showed higher activity than HC, which might have indicated preserved DM due to compensatory activity. Conclusion: We identified dysregulated activity linked to impairment in specific cognitive stages of reward-related DM. The link of brain activity and impaired DM in areas with MS-induced GM loss suggests that this deficit might be tightly coupled to MS neuropathology. [ABSTRACT FROM AUTHOR]

Background: Previous studies have postulated an association between dentate nucleus T1 hyperintensity and multiple sclerosis (MS)-related progressive neurodegeneration. Therefore, MS patients have been excluded from most studies investigating brain deposition of gadolinium-based contrast agents (GBCAs). Objective: To study the hypothesis that dentate nucleus T1 hyperintensity in MS patients is associated with GBCA administration. Methods: In a cohort of 97 MS patients, the dentate-to-pons signal intensity ratio (DPSIR) was calculated for 265 consecutive T1-weighted magnetic resonance (MR) scans (including sessions with and without the administration of GBCA). Patients exclusively received either gadopentetate dimeglumine (Gd-DTPA, linear) or gadobutrol (Gd-BT-DO3A, macrocyclic). Results: In patients receiving Gd-DTPA, DPSIR increased significantly between the first and the last scan (+0.009, p < 0.001), and following magnetic resonance imaging (MRI) with Gd-DTPA administration as compared to following an MRI without Gd-DTPA administration (+0.005 vs −0.001; p = 0.022). Additionally, there was a positive linear relationship between the number of Gd-DTPA administrations and the increase in DPSIR (p = 0.017). No DPSIR increase was observed after Gd-BT-DO3A administration. Conclusion: Dentate nucleus T1 hyperintensity in MS patients is associated with Gd-DTPA (but not Gd-BT-DO3A) administration, suggesting an alternative explanation for the association of T1 hyperintensity with disease duration and severity. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the association of peripapillary retinal nerve fibre layer (RFNL) thinning and macular ganglion cell layer (GCL) with white and grey matter brain volume in multiple sclerosis (MS) patients with and without an optic neuritis history. The study performed retinal examination with spectral domain optical coherence tomography. The result of the study shows that the GCL and RNFL were linked to whole brain as well as grey and white matter atrophy.

The article discusses research which investigate alterations of periventricular small blood vessel appearance in relation to T2 lesion count in patients with multiple sclerosis and clinically isolated syndrome using the 7 Tesla magnetic resonance imaging (MRI) technique. The study showed significantly decreased venous density in patients with multiple sclerosis patients. It revealed that alterations of venous density in multiple sclerosis in inversely associated with T2 lesion count.