AIM: To investigate the opportunity of the concomitant strabismus operation and the function in the treatment of strabismic amblyopia through analyzing the changes of binocular summation of pattern visual evoked potential(P-VEP)before and after the surgery of concomitant strabismus.

METHODS: In this retrospective study we investigated 67 cases admitted in our hospital. All patients were less than 18a and the postoperation squint angle was less than ±10^△. Patients were divided into three groups according to the strabismus type, age, and amblyopia degree. P-VEP binocular summation response was recorded in all cases, to observe the changes of the binocular summation response of P-VEP before strabismus surgery and 1mo, 3mo after surgery. The P-VEP response of binocular /monocular(B/M)ratio was taken as an evaluation index.

RESULTS: B/M value of three groups all improved obviously 1mo after surgery, which the difference showed statistical significant(P<0.01). 1)After 3mo surgery, B/M value in esotropia group was higher than that in exotropia group(P<0.05). 2)After 3mo surgery, B/M value in ≤6a group was higher than that in >12a group(P<0.05). 3)After 1mo surgery, B/M value in severe amblyopia group was higher than that in mild group(P<0.05). After 3mo surgery, B/M value in severe amblyopia group was higher than that in mild group significantly(P<0.01).

CONCLUSION: Concomitant strabismus surgery is suggested to be performed before 6 years old when the patients are difficult to improve the vision after amblyopia treatment, especially with the severe amblyopia and esotropia(accommodative esotropia must be excluded). The early operation is better to amblyopia treatment and binocular vision recovery.