Surgical management of clinically significant hypertropia associated with exotropia

Abstract

Purpose To report the surgical treatment of hypertropia coexisting with exotropia, with either vertical offset surgery or additional vertical muscle surgery simultaneous to correction of the exotropia. Methods A total of 35 patients with exotropia and hypertropia who underwent a horizontal muscle surgery for exotropia were included. To determine efficacy in resolving a vertical deviation in patients with exotropia, 28 patients were compared in 2 groups: those who underwent horizontal muscle surgery with vertical offset and those who underwent horizontal muscle surgery with additional vertical muscle surgery. An additional 7 patients who had exotropia and hypertropia but did not undergo vertically corrective surgery were included for comparison. Results Vertical offset of horizontal rectus muscles (4 mm) resulted in 8Δ correction of the distance hypertropia. Vertical rectus muscle recession used in the treatment of larger hypertropic deviations with exotropia had a 3Δ correction per 1 mm of recession. Success rates for hypertropia correction were similar between groups, 63% vertical offset and 71% vertical muscle groups; overcorrections occurred in 29% of the vertical muscle group. The vertical correction in both groups was stable in 88% over 6 months postoperatively. Conclusions Vertical offset of the horizontal muscles simultaneous with exotropia correction has a beneficial effect in small-angle hypertropia (<14Δ). Vertical rectus muscle surgery in patients with hypertropia greater than 10Δ had equivalent success; however, in intermittent exotropia the hypertropia was prone to overcorrection.

Resolution of hypertropia with correction of intermittent exotropia

“…Kushner warned against vertical or cyclovertical surgery in this situation. We have previously described a high rate of overcorrection of the vertical deviation when the surgical plan involves operating for the hypertropic component in intermittent exotropia 1. Indeed, Moore et al described the same resolution of the vertical component when patients undergo preoperative prism adaptation for the horizontal deviation alone.…”

“…In 14 patients the vertical deviation in primary position was 4 prism dioptres or less. Five patients had concurrent vertical muscle surgery, two were diagnosed with superior oblique palsy and three were previously reported and included in this study 1. A retrospective case review was conducted of the remaining 17 patients.…”

“…This report analyses the surgical manifestations of patients with intermittent exotropia who additionally present with a clinically significant hypertropia, unrelated to oblique dysfunction, dissociated vertical deviation or paretic muscle. We have defined ‘clinically significant’ vertical deviations as those with a magnitude of 5 prism dioptres or greater in primary position, regardless of the magnitude of deviation in other fields of gaze 1. Previously, 5 prism dioptres was determined as the baseline, which may initiate contemplation of surgical intervention, even if asymptomatic 2.…”

Intermittent exotropia with a positive Bielschowsky head-tilt test

“…The condition involves a specific set of sensorimotor abnormalities 1. For example, vertical deviations often coexist with exotropic horizontal strabismus, and they have been described in up to 50% of patients who present with IXT 2. The amount of vertical deviation varies.…”

Exotropia-Hypotropia Complex in High Myopia

“…Several studies have examined the treatment of vertical deviations in association with horizontal strabismus. 12,13 However, none of these studies have specified the type of refractive error or axial lengths of their patients. Hence, it is difficult to draw direct comparisons between these groups of patients and those in our study.…”