The response of new vessels arising from the optic disc to pituitary ablation was studied in sixty-six eyes of forty-five patients over six months to four years. The response was related to the extent of pituitary ablation graded as complete, intermediate or slight from endocrine tests done three months post-implant.
Following complete ablation there was a significant improvement in new vessels. A similar trend (but not significant values) was observed in partially ablated patients, while those with slight ablation showed no change.
Retinitis proliferans deteriorated in all groups, but least in those with complete and most in those with slight ablation. The mean visual acuity in the completely ablated group did not change, while it deteriorated significantly in the slight ablation category.
Patients under forty years of age at the time of the operation benefited more than those over forty.
It is concluded that new vessels on the disc respond to complete and intermediate pituitary ablation, complete ablation being superior in its effectiveness.