White matter volume is decreased in the brain of patients with neuromyelitis optica

Background Neuromyelitis optica (NMO) is an inflammatory disease involving predominantly the spinal cord and optic nerves. Whether patients with NMO have a loss in white or grey matter (GM) volumes remains to be determined. Methods Thirty patients with NMO, 30 healthy subjects matched for age and gender, 21 patients with multiple sclerosis (MS) and 20 patients with a clinically isolated syndrome (CIS) were studied. We applied a SIENAX post-treatment software. We compared white matter (WM) and GM volumes between groups and explored correlations of changes in NMO patients with age, gender, duration, disease severity, visual acuity and T2 hyperintensities. We also performed a voxel-based morphometry (VBM) analysis to identify the regions affected by loss of volume. Results White matter volume was significantly reduced in patients with NMO (764.4 ± 58.3 cm3) compared to healthy subjects (843.1 ± 49.3 cm3) (P