Several changes to networks in the brain that can distinguish neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS) from each other, as well as healthy controls, have been identified and published in Scientific Reports.
White matter network analysis using magnetic resonance imaging revealed that patients with MS had more brain regions with altered network topologies than patients with NMOSD when compared to healthy controls. Patients with MS tended to have more altered connections within the thalamus and inferomedial temporal regions.
“[White matter] network disruption was more widespread and severe in MS than in NMOSD,” the authors said. “Significant disconnections within inferomedial temporal regions might be a differentiated feature in MS from NMOSD.”
A total of 2 subnetworks were identified that could differentiate between NMOSD and MS. The first subnetwork included mostly the left temporo-parietal-occipital lobes plus bilateral involvement of the precuneus, cuneus, superior occipital gyrus, and calcarine cortex. These systems incorporated parts of the memory, visual/visuospatial, and default-mode systems.
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Patients with MS had a higher number of edges in subnetwork 1 with significant decreases than NMOSD when compared to healthy controls. Post hoc tests showed that patients with MS had significant decreases in 28 out of 29 edges in this network while patients with NMOSD only had 13 out of 29 edges.
The second subnetwork primarily consisted of the right-side counterparts of the first subnetwork and included edges between the hippocampus, parahippocampal gyrus, or thalamus. This subnetwork was only disrupted in patients with MS and 4 out of the 5 edges were significantly affected.
Changes in several subnetwork edges, including the connection between the right and left precuneus, were also significantly correlated with Expanded Disability Status Scale scores as well as the duration of disease in both patients with NMOSD and MS. These characteristics had a positive correlation with characteristic path length and a negative correlation with the other global properties of the network including total strength, clustering coefficient, local efficiency, and global efficiency.
During the study, a total of 68 patients with relapsing-remitting MS, 50 with NMOSD, and 26 healthy controls were recruited. There was no difference in sex between the groups but the NMOSD group was older than the MS and healthy control groups (P <.001 and P =.004, respectively).
Cho EB, Kim D, Jeong B, et al. Disrupted structural network of inferomedial temporal regions in relapsing-remitting multiple sclerosis compared with neuromyelitis optica spectrum disorder. Sci Rep. 2022;12(1):5152. doi:10.1038/s41598-022-09065-4