Clinical investigation of surgery for intermittent exotropia.

OBJECTIVE: To investigate the time and postoperative binocular vision of strabismus surgery for children with intermittent exotropia (X(T)).
METHODS: A retrospective investigation was conducted in 80 child patients with intermittent exotropia. Pre- and postoperative angles of deviation fixating at near (33 cm) and distant targets (6 m) were measured with the prolonged alternate cover testing. The binocular function was assessed with synoptophore. Twenty-one patients took the postoperative synoptophore exercise.
RESULTS: (1) A week after surgery, 96.2% of the 80 patients had binocular normotopia, while a year after surgery, 91.3% of the 80 patients had binocular normotopia; (2) Preoperatively, 58 patients had near stereoacuity, while postoperatively, 72 patients achieved near stereoacuity (P<0.05); (3) Preoperatively, 64 patients had Grade I for the synoptophore evaluation and postoperatively, 76 patients achieved Grade I. Meanwhile, 55 patients had Grade II preoperatively and 72 achieved Grade II postoperatively. For Grade III, there were 49 patients preoperatively and 64 patients postoperatively (P<0.05); (4) Patients of 5-8 years old had a significantly better recovery rate of binocular vision than those of 9-18 years old (P<0.05); (5) Patients taking postoperative synoptophore exercise had a better binocular vision than those taking no exercise (P<0.05).
CONCLUSIONS: (1) Strabismus surgery can help to preserve or restore the binocular vision for intermittent exotropia; (2) Receiving the surgery at young ages may develop better postoperative binocular vision; (3) The postoperative synoptophore exercise can help to restore the binocular vision.