Acquired color vision defects in compressive optic neuropathy

Abstract

We studied preoperative color vision in 29 patients treated neurosurgically for intracranial pathology with compression of the visual pathways in the chiasmal region. Twenty-four patients (83%) had a significant acquired color vision defect: five cases of meningioma, five cases of pituitary adenoma, five cases of craniopharyngioma, three cases of aneurysm, one case of dysgerminoma, one case of neuroblastoma, and one case of carcinoma. Five patients (17%) had no significant color vision defect: three cases of pituitary adenoma and two cases of craniopharyngioma. Color vision defects usually occurred in eyes with prechiasmal field defects, but a lower incidence was found in eyes with bitemporal and homonymous field defects. A decreasing incidence of color vision disturbance was found in eyes with field defects caused by, respectively, meningioma, carotid aneurysm, pituitary adenoma and craniopharyngioma. Normal color vision did not rule out advanced field defects caused by pituitary adenoma and craniopharyngioma. The differences in color vision in compressive optic neuropathy are probably attributable to differences in the location of the tumors in relationship to both the optic pathway and its vasculature.