fMRI demonstrates diaschisis in the extrastriate visual cortex.
OBJECTIVE
Diaschisis may play a critical role in motor recovery, but in other cortical networks its role is unclear. Some visual system regions, such as the fusiform gyri, depend on intact striate regulation for their function. We evaluated visual cortical diaschisis by serial functional magnetic resonance imaging.


METHODS
Using a high-level visual activation task, we studied patients with visual system stroke by functional magnetic resonance imaging within 10 days and at 6 months. Their activation data were compared with those of age-appropriate healthy control subjects.


RESULTS
Three patients were studied. In the short term, patients displayed absent or significantly reduced activation in ventral extrastriate sites. All displayed a restitution of activation to these sites at 6 months.


CONCLUSIONS
Functional magnetic resonance imaging revealed evidence of ipsilesional cortical diaschisis within ventral extrastriate sites. Diaschisis may play an under-recognized role in visual recovery after stroke.
Brodtmann
Amy
A
Puce
Aina
A
Darby
David
D
Donnan
Geoffrey
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001931:Brain Mapping; D013181:Cortical Spreading Depression / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D020127:Recovery of Function / Q000502:physiology; D020521:Stroke / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology*; D015354:Vision, Low / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D014793:Visual Cortex / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology*; D014795:Visual Pathways / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology