Extraocular Muscle Surgery for Extorsion after Macular Translocation Surgery: New Surgical Technique and Clinical Management

Abstract

To report a new extraocular muscle surgery procedure for large-angle extorsion, and clinical management of subjective tilt and diplopia after full macular translocation (MT360). Consecutive retrospective case series. Seven patients with downward MT360 were evaluated after MT360, both before (preoperative) and after (postoperative) extraocular muscle surgery, with at least 6 months' follow-up. Information gathered included demographics, visual acuity, ocular motility, torsion by Maddox rod, ocular history, and symptoms of visual disturbance. Surgery on extraocular muscles was performed based on the magnitude of torsion measured after MT360 surgery. Maddox rod testing of torsion after MT360, and both preoperative and postoperative extraocular muscle surgery. Mean preoperative torsion was reduced from 45.4+/-11.3 degrees to 8.3+/-4.8 degrees (at 6 months after MT360) (P = 0.03). Extraocular muscle surgery slightly reduced the mean hypertropia of the operated eye (preoperative, 20+/-10 prism diopters [PD], vs. postoperative, 11+/-6 PD) (P = 0.06). Mean exotropia was affected minimally by extraocular muscle surgery (preoperative, 22+/-31 PD, vs. postoperative, 20+/-24 PD). Three patients required a second extraocular muscle surgery (performed on the fellow eye) to correct residual extorsion and diplopia. Overall, 85% (6/7) of patients were free of both diplopia and tilt after 1 or 2 extraocular muscle surgeries. Although our patients continued to have significant horizontal/vertical strabismus postoperatively, the extraocular muscle surgery performed was successful in reducing the torsional misalignment enough such that the remaining diplopia could be successfully ignored or suppressed.