Journal of Neuro-Ophthalmology, December 1981, Volume 1, Issue 4

Visual-evoked responses. A new abnormality with focal retinal damage.

A new monocular pattern-shift visual-evoked response abnormality seen with focal retinal damage is described in a patient with a right parietal malignant astrocytoma treated with 3 pulse doses of unilateral intra-arterial carotid BCNU to a cumulative dose of 750/mg/M2. Ophthalmoscopy showed a minimally blurred right optic disc edge with a large flame-shaped hemorrhage in the right superior quadrant at 11 o'clock, one disc diameter from the disc. Visual-evoked response with right eye stimulation demonstrated prolongation of the major P-100 wave in the right occipital area but not the left. Left eye stimulation was normal at both occipital electrodes. Unilateral occipital slowing ipsilateral to pattern shift presentation--with normal evoked responses from the contralateral eye--was seen in a patient with pathology of the retina. Abnormalities of visual-evoked responses must be interpreted in the context of a good ophthalmoscopic examination and not attributed solely to pathology in the optic nerve and more central structures of the nervous system.