ABSTRACT
Background:Reports on the aquaporin-4 immunoglobulin G (AQP4-IgG) status for cognitive performance and neuroimaging correlations are limited in neuromyelitis optica (NMO) and multiple sclerosis (MS) literature. Methods: Cognitive results of 19 MS and 15 NMO patients were compared with 47 agematched controls. Apparent diffusion coeffi cient (ADC) values were used to delineate gray matter and white matter damages and correlate with neuropsychological results. Results: Verbal memory test showed signifi cant differences between MS and NMO in the late registration, early and delay recall (p<0.05), while their retention rates were even. In MS, ADC values were signifi cantly elevated in the dorsolateral prefrontal and occipital gray matter which was in contrast with NMO group that showed elevation in the dorsolateral prefrontal gray matter and parieto-occcipital white matter. AQP4-IgG status exerted a limited effect on ADC values and neuropsychological results. Conclusions: Verbal memory test might be helpful in differentiating NMO and MS. ADC values can be used as a surrogate marker for tissue injury in NMO and MS since they were in line with the cognition scores. Anatomical regions with elevated ADC values were different in NMO and MS.