Abnormal connectivity of the visual pathways in human albinos demonstrated by susceptibility-sensitized MRI.
We studied activation of the human visual cortex (VC) using susceptibility-sensitized MRI at 1.5 Tesla. Three albinos and six healthy controls underwent a series of monocular and binocular photic flash stimulation. Monocular stimulation in albinos caused predominant contralateral activation with a small, well-delineated area in the anterior part of the VC in the ipsilateral hemisphere. This finding was consistent with a chiasmal crossing anomaly in albinism. All controls had symmetric patterns of activation during monocular stimulation. Functional MRI represents a promising method for evaluation of the visual pathways in humans.
Hedera
P
P
Department of Neurology, University Hospitals of Cleveland, OH.
Lai
S
S
Haacke
E M
EM
Lerner
A J
AJ
Hopkins
A L
AL
Lewin
J S
JS
Friedland
R P
RP
D000293:Adolescent; D000328:Adult; D000417:Albinism / Q000175:diagnosis / Q000503:physiopathology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009431:Neural Conduction / Q000502:physiology*; D010775:Photic Stimulation; D014793:Visual Cortex / Q000033:anatomy & histology / Q000473:pathology / Q000503:physiopathology*