Hang-back recession of inferior oblique muscle in V-pattern strabismus with inferior oblique overaction.

INTRODUCTION: Although hang-back recession has widely been used as a weakening procedure on extraocular muscles, its effectiveness has mostly been studied for rectus muscles. We report a surgical technique for recessing the inferior oblique muscle and evaluate its effectiveness in V-pattern strabismus with inferior oblique overaction (IOOA).

METHODS: Fifteen patients with V-pattern strabismus and IOOA, 7 with V exotropia, and 8 with V esotropia underwent hang-back recession of inferior oblique muscle in addition to horizontal muscle surgery when required. The surgical technique consisted of free suspension of one or both inferior oblique muscles 10 mm along their physiological path using 6-0 polyglactin 910 sutures bridging the cut ends of muscle.

RESULTS: The mean preoperative V pattern in the V-exotropia group was 22(Delta) +/- 6(Delta) and 25(Delta) +/- 7(Delta) in V-esotropia group. The mean correction of V pattern after a mean follow-up period of 8 +/- 1 months was 19(Delta) +/- 2(Delta) for the V-exotropia group and 22(Delta) +/- 7(Delta) months for the V-esotropia group. Mean correction of IOOA in the V-exotropia group was 18(Delta) +/- 5(Delta); in the V-esotropia group, mean correction was 20(Delta) +/- 6(Delta) in the right eye and 18(Delta) +/- 2(Delta) in the left eye.

CONCLUSIONS: Hang-back recession of inferior oblique is another surgical procedure for correction of both V pattern and IOOA in V-pattern strabismus.