Management of ocular torsion and diplopia after macular translocation for age-related macular degeneration: prospective clinical study

Abstract

Purpose To report the results of a prospective clinical series to evaluate the management of both torsion and diplopia in a large group of patients after full macular translocation (FMT) and extraocular muscle surgery. Design Prospective interventional case series. Methods Information gathered included demographic, visual acuity, ocular motility, torsion by Maddox rod, ocular history, and symptoms of visual disturbance. Surgery on two, three, or four extraocular muscles was performed based on the magnitude of torsion measured after FMT surgery. Results Fifty-three patients were included for both objective and subjective outcomes and were evaluated after FMT, both before (preoperative) and after (postoperative) extraocular muscle surgery. Preoperative torsion for two- (n = 6), three- (n = 8), and four-muscle (n = 39) surgery groups was 21.2 ± 4.6, 30.0 ± 6.3, and 40.5 ± 8.7 degrees, respectively. At 6 months, postoperative residual torsion was significantly reduced in each group (to 3.4 ± 3.2, 5.6 ± 5.5, and 4.5 ± 6.8 degrees, respectively, for two-, three-, and four-muscle groups). Muscle surgery reduced mean hypertropia from 17 ± 6 prism diopters preoperative to 4 ± 10 prism diopters postoperative ( P < .0001); mean exotropia was mildly reduced from 20 ± 9 prism diopters preoperative to 13 ± 11 prism diopters postoperative ( P < .01). Subjective data regarding diplopia and tilted vision after FMT and muscle surgery were available on an additional 10 patients (n = 53 + 10 = 63). Overall, 41% (26/63) of these were free of both diplopia and tilt, whereas only 5% (3/63) had both symptoms constantly. Conclusions Extraocular muscle surgery is effective at relieving the variable amounts of torsion produced by FMT when graded to match preoperative torsion. The majority of patients were free of disabling tilt and diplopia after extraocular muscle surgery.