Brain magnetic resonance imaging features in multiple sclerosis and neuromyelitis optica spectrum disorders patients with or without aquaporin-4 antibody in a Latin American population.

•Scarce evidence comparing brain atrophy in positive and negative AQP4 patients.•Brain and lesion volume measurements taken by automated software.•Analysis performed in a Latin American population.•No differences in lesion distribution at onset and brain volumes during follow-up.•Differences observed in lesion distribution and brain volumes between NMOSD and MS.