Characteristic brain magnetic resonance imaging abnormalities in central nervous system aquaporin-4 autoimmunity.
BACKGROUND
Although neuromyelitis optica has been traditionally regarded as a disease without brain involvement, brain abnormalities are not uncommon in patients with neuromyelitis optica-related disorders.


METHODS
We aimed to characterize the brain magnetic resonance imaging (MRI) abnormalities in neuromyelitis optica spectrum disorder patients who are seropositive for anti-aquaporin-4 autoantibody (AQP4 Ab). Of 236 consecutive patients with inflammatory demyelinating central nervous system diseases, we retrospectively analyzed MRI characteristics of 78 patients who were seropositive for AQP4 Ab.


RESULTS
For an average observational period of 6.3 years, 62 patients (79%) had brain lesions on MRI. Twenty-four patients (31%) had brain MRI abnormalities at the onset of disease, and 35 (45%) had symptomatic brain involvement. Characteristic brain MRI abnormalities were classified into five categories: (1) lesions involving corticospinal tracts (e.g. posterior limb of internal capsule and cerebral peduncle (44%); (2) extensive hemispheric lesions likely due to vasogenic edema (29%); (3) periependymal lesions surrounding aqueduct and the third and fourth ventricles (22%); (4) periependymal lesions surrounding lateral ventricles (40%); and (5) medullary lesions, often contiguous with cervical lesions (31%). Fifty-four patients (69%) showed at least one kind of brain abnormality among the five characteristic MRI lesions. Ten patients showed gadolinium-enhancing lesions, which were characterized by multiple patchy enhancing patterns with blurred margins.


CONCLUSIONS
In central nervous system AQP4 autoimmunity, brain MRI abnormalities were more common than is generally appreciated and were characterized by their unique localization and configuration.
Kim
Woojun
W
Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea.
Park
Min Su
MS
Lee
Sang Hyun
SH
Kim
Su-Hyun
SH
Jung
In Ja
IJ
Takahashi
Toshiyuki
T
Misu
Tatsuro
T
Fujihara
Kazuo
K
Kim
Ho Jin
HJ
D000328:Adult; D017668:Age of Onset; D000368:Aged; D051401:Aquaporin 4 / Q000276:immunology*; D001327:Autoimmune Diseases / Q000276:immunology* / Q000473:pathology*; D001921:Brain / Q000473:pathology*; D003287:Contrast Media; D020278:Demyelinating Autoimmune Diseases, CNS / Q000276:immunology / Q000473:pathology; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis / Q000276:immunology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000473:pathology; D012008:Recurrence; D012189:Retrospective Studies; D013116:Spinal Cord / Q000473:pathology
D051401:Aquaporin 4; D003287:Contrast Media; D007074:Immunoglobulin G; D019786:Gadolinium DTPA