Visual recovery after treatment for pituitary adenoma

Visual functions were studied pre- and post-operatively in 128 patients treated for pituitary adenoma with operations by intracranial (89 patients) or transsphenoidal approach (39 patients). Most patients were given post-operative irradiation. Follow-up was 6 months or more. Visual field defects were seen pre-operatively in 85% of the patients operated intracranially and in 36% of the patients operated transsphenoidally. Visual acuity was reduced, at least in one eye, in 64% of the patients in the former group and in 26% of the latter group. Additional diagnostic information was obtained from recordings of visually evoked cortical potentials. After intracranial operations visual acuity was normalized or improved in 65% and visual fields in 82% of the patients with pre-operative visual defects. After transsphenoidal operations the corresponding values were 56% and 92%. A detailed analysis of the visual acuity showed that eyes with optic atrophy pre-operatively improved to a very limited extent. Other pre-operative ophthalmological disturbances were of much less prognostic significance. Improvement of vision was often gradual and could continue for more than a year after treatment. Even if visual acuity and visual fields had been completely restored, visually evoked cortical potentials could remain impaired, indicating that evoked potentials might be a very sensitive test for the evaluation of visual recovery.