The time course of visual field recovery following transphenoidal surgery for pituitary adenomas: predictive factors for a good outcome.

OBJECTIVE To report the quantitative assessment of visual fields (VF) in patients with pituitary macroadenomas, and the time course and predictive factors for recovery of vision. METHODS Retrospective study of 41 patients with pituitary adenomas and visual disturbance. Patients underwent pre- and postoperative VF assessment at one week, three to six months, one year, two years, and five years using the Humphrey field analyser, which gives a quantitative measure of VF in each quadrant. RESULTS 36/41 patients (88%) presented with a visual disturbance. Mean (SEM) duration of symptoms was 94 (50) weeks (range 0.5 to 1500); 12 (29%) had optic atrophy at presentation. Impairment of VF was greatest in the upper temporal quadrant, followed by the lower temporal. VF recovery was progressive and apparent even at the five year follow up (p<0.001). Overall, VF returned to normal in 35% of eyes, improved in 60%, and remained unchanged in 5%. Patients whose VF returned to normal had a shorter duration of symptoms (16 (5) v 137 (56) weeks; p<0.05), better preoperative visual acuity (p<0.05), and a smaller degree of impairment in preoperative lateral quadrant VF (p<0.01) than those whose VF only improved. On multivariate analysis, the only predictive factor for VF recovery was the degree of impairment in VF preoperatively. CONCLUSIONS Transphenoidal surgery for pituitary macroadenoma results in a progressive recovery of VF in 95% of patients. The extent of the VF recovery is mainly dependent on the preoperative VF deficit, which emphasises the need for early intervention in these patients.