Conclusion:Symmetric recession of internus in alternative esotropia can improve the success rate and the binocular vision function.

交替性内斜视手采用同等量内直肌，不但手成功率高，而且有利于手双眼三级功立。

Objective To study the optimal time for operation of intermittent exotropia, so that we can orthopia strabismus and attain normal binocular function.

目探讨间歇性外斜视最佳手时机，以求达到矫正斜视并获得完善双眼单视功目。