Subregional Structural And Connectivity Damage In The Visual Cortex In Neuromyelitis Optica

Objectives: Patients with neuromyelitis optica(NMO)have shown structural and functional impairments in the visual cortex.We aimed to characterize subregional grey matter volume(GMV)and resting-state functional connectivity(rs FC)changes in the visual cortex in NMO.Methods: Thirty-seven NMO patients and forty-two controls underwent structural and functional MRI scans.The GMV and rs FC of each visual subregion were compared between the groups.Results: Compared with controls,NMO patients had GMV reductions in the bilateral V1,V2,V3 d,VP,and LO and in the left V3 A.In canonical visual pathways,the relatively low-level subregions showed more significant GMV reductions than did the high-level ones.Regardless of GMV correction,NMO patients showed reduced rs FC in the bilateral LO and V4 v and in the left V2.The GMVs of the bilateral V1 and LO and of the left V2 and V3 d were negatively correlated with clinical disability in NMO patients;these correlation coefficients were associated with hierarchical positions in the visual pathways.Conclusions: These findings suggest that in NMO,the low-level visual subregions have more severe structural damage;structural damage is not the only factor affecting rs FC alterations of visual subregions;GMV reduction in the low-level visual subregions has the highest predictive value for clinical disability.