Neuro-ophthalmological assessment of vision before and after radiation therapy alone for pituitary macroadenomas.

Between 1972 and 1988, 25 patients were treated by radiation therapy (RT) alone for pituitary macroadenomas causing visual impairment. Twenty-three patients were evaluated by a neuro-ophthalmologist before treatment and at the time of follow-up review. Radiation treatment consisted of 4000 to 5000 cGy over 4 to 5 weeks. The median follow-up period was 36 months (range 2 to 192 months). Eighteen patients (78%) experienced visual field improvement. Deterioration occurred in four patients due to tumor recurrence, tumor hemorrhage, possible optic nerve necrosis, and optic chiasm herniation. Visual field improvement occurred predominantly in patients whose pretreatment visual field defects were less than a dense hemianopsia, who did not have diffuse optic atrophy, and who were younger than the median age of 69 years (p less than 0.001). Visual acuity improvement occurred in patients without diffuse optic atrophy, with only mild impairment of the visual acuity, and with only mild visual field loss prior to RT (p less than 0.002). It is concluded that there is a subset of patients with pituitary macroadenomas and visual impairment for whom primary RT is a treatment option.