Functional magnetic resonance imaging in homonymous hemianopsia

American Journal of Ophthalmology
A MikiH Abe

Abstract

We performed functional magnetic resonance imaging associated with brain activity to evaluate the abnormality of the visual pathway in hemianoptic patients. We studied five patients with homonymous hemianopsia caused by retrochiasmal lesions and five control subjects. On the basis of a blood oxygenation level-dependent contrast mechanism, magnetic resonance imaging was performed with a standard clinical 1.5-tesla system. We evaluated the asymmetrically increased signal intensities in the calcarine cortex during visual stimulation and compared them with the findings of Goldmann perimetry. Cortical activations with a marked interhemispheric contrast of the primary visual cortex consistent with the visual field defects were observed in three of the five patients. In two of the patients without macular field preservation in the defective hemifield, functional magnetic resonance imaging showed an absence of response in the primary visual cortex of the affected side. In the patient with superior quadrantanopsia, we could detect clear laterality by selecting the imaging plane inferior to the calcarine fissure. The other two hemianoptic patients with macular sparing showed symmetric responses. These findings suggest that functional mag...Continue Reading

Citations

May 16, 2000·Journal of Neurology, Neurosurgery, and Psychiatry·G Kerkhoff
Nov 26, 2008·Neurorehabilitation and Neural Repair·Amy BrodtmannGeoffrey Donnan
May 4, 2002·Stroke; a Journal of Cerebral Circulation·Gereon NellesH Christoph Diener

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