ABSTRACT
AIM:To investigate the surgical method and extent of reoperation in the concomitant strabismus patients with surgical under-correction and over-correction. METHODS: Ninety - six concomitant strabismus patients with surgical under - correction and over -correction were recruited in this study, which included 41 males and 55 females, aged 21. 90±14. 70. All individuals underwent routine eye examinations for strabismus before the surgery. Among the cases with concomitant esotropia, there were over-correction in 23 cases, under-correction in 15 cases. Among the cases with concomitant exotropia, there were over-correction in 28 cases, under - correction in 30 cases. The method of reoperation were based on angle of deviation, the method of original operation and acute visual acuity of patients. RESULTS:In over - correction cases with concomitant esotropia, medial rectus muscle of 9 cases were advanced, the corrective extent was (5. 51±2. 63) ? / mm;9 cases were performed advance of medial rectus muscle and recession of lateral rectus muscle, the corrective extent was (6. 25±1. 59) ? / mm; 3 cases were performed resection of medial rectus muscle and recession of lateral rectus muscle, the corrective extent was (4. 26±1. 04) ? /mm; only 2 cases were performed recession of lateral rectus muscle, the corrective extent was (4. 21±1. 91) ? /mm. In under - correction cases with concomitant esotropia, 6 cases were performed resection of lateral rectus muscle, the corrective extent was (4. 03±0. 98) ? /mm; 6 cases were performed resection of lateral rectus muscle and recession of medial rectus muscle, the corrective extent was (6. 86 ± 1. 32) ? / mm; 3 cases were performed recession of medial rectus muscle, the corrective extent was ( 4. 33 ± 0. 29 ) ? / mm. In over -correction cases with concomitant exotropia, 16 cases were performed advance of lateral rectus muscle, the corrective extent was (5. 37 ± 1. 56) ? / mm; 6 cases were performed recession of medial rectus muscle, the corrective extent was (6. 29 ± 3. 68) ? / mm; 5 cases were performed advance of lateral rectus muscle and recession of medial rectus muscle, the corrective extent was (5. 46±1. 78) ? / mm; 1 case were performed resection of lateral rectus muscle, the corrective extent was 5. 00? / mm. In under - correction cases with concomitant exotropia, 12 cases were performed resection of medial rectus muscle, the corrective extent was (4. 47 ± 0. 54) ? / mm; 16 cases were performed recession of lateral rectus muscle and resection of medial rectus muscle, the corrective extent was ( 5. 11 ± 0. 75 ) ? / mm; 2 cases were performed recession of lateral rectus muscle, the corrective extent was (2. 65±0. 42) ? / mm. CONCLUSION: In reoperation of concomitant strabismus patients with over-correction, weakening or/and strengthening the horizontal muscle which were performed surgery before has a greater and more unstable surgical corrective extent. While In reoperation of concomitant strabismuspatients with under -correction, weakening or/ and strengthening the horizontal muscle which were not performed surgery has a normal corrective extent as usual.