Perichiasmal tumors: diagnostic and prognostic features.

A review of 49 tumors compressing the intracranial optic nerve, optic chiasm, or optic tract revealed that the majority of patients had symptoms and signs of visual loss predominantly affecting one eye. Seventy-seven per cent of patients had a relative afferent pupillary defect (RAPD), and 96% had a hemianopic defect in at least one eye. All patients had either a RAPD or a hemianopic defect. The junctional pattern of visual field defects was nearly as common (39%) as the classic bitemporal pattern (46%). Many fields contained a mixture of nerve fiber bundle and hemianopic defects; the hemianopias tended to obscure the coexisting nerve fiber bundle defects. Poor preoperative acuity predicted a relatively poor postoperative acuity, but 95% of the patients had 20/40 or better acuity in at least one eye after operation.