Peripheral homonymou cotoma from a cavernou angioma affecting fiber uberving the intermediate region of the triate cortex

PURPOE: To report the cae of a pure peripheral homonymou viual field defect and to delineate the repreentation of the viual field on the triate cortex. METHOD: Obervational cae report. Neuro-ophthalmologic and neuroimaging aement of a patient with a cavernou angioma of the right parieto-occipital lobe. REULT: The patient had left homonymou cotoma located 40 degree to 60 degree from the vertical meridian. Neuroimaging indicated that the leion wa affecting the optic radiation at their termination in the intermediate portion of the triate cortex or the triate cortex itelf. CONCLUION: Homonymou field defect are typically located within 10 degree of fixation. Thi patient had a peripheral homonymou field defect from damage to the intermediate triate cortex. Correlation of the neuroimaging finding in thi cae with the mot commonly ued map of the repreentation of the viual field on the triate cortex ugget that none of the map correctly predict the location or extent of leion that affect the intermediate portion of the cortex.