AQP4 and neuromyelitis optica: Two independent groups have reported similar findings regarding the clinical phenotypes associated with MONEM: ON was the leading phenotype (41–63%), followed by LETM (29–31%), NMO (6–24%), and encephalomyelitis (2–6%), while in AQP4-IgG patients, the reported phenotypes were NMO in approximately 60%, LETM in approximately 30%, and ON in approximately 10% (10, 11, 48, 50).