Recession of the lateral recti. Effect of Preoperative fusion and distance-near relationship.

The importance of both preoperative fusion and the distance-near alignment relationship to the results of recession of the lateral recti for correction of exodeviation was studied. Satisfactory alignment was achieved after this procedure in 78% of patients with constant exodeviation and 80% of patients with intermittent exodeviation. In each fusion status, initial overcorrection of up to 20 prism diopters gave the highest percentage of good results (constant exodeviation patients, 88%; intermittent, 89%). Fifty-six percent of the satisfactorily realigned constant exodeviation patients and 69% of intermittent exodeviation patients remained satisfactorily realigned over an average follow-up interval of five years. If convergence insufficiency was present, satisfactory realignments noted at five to eight weeks could be maintained thereafter in 40% of patients. Where there was no preoperative convergence insufficiency, satisfactory results were maintained in 64% of patients with "high" and 68% of patients with "normal" distance-near ratios.