title: Unilateral surgery for exotropia with convergence weakness.
abstract: We prospectively studied 14 patients whom we treated surgically for exotropia (XT) with convergence weakness measuring at least 8 delta for distance (6 m) that increased at least 8 delta at near (1/3 m). Surgery involved lateral rectus recessions and medial rectus strengthenings (advancements or resections) to eliminate distance and near deviations and simultaneously collapse near-distance differences. The medial rectus was strengthened more than the lateral rectus was recessed; amounts were based on the near deviation. Minimum follow-up was 6 months after surgery. Preoperatively, the mean XT at distance was 18.3 delta (range, 8 to 35 delta) and at near 30.1 delta (range, 16 to 50 delta). At latest follow-up evaluations the mean distance deviation was 0.1 delta XT and at near 1.8 delta XT. The near-distance differences were reduced by a mean of 10.2 delta; the mean postoperative difference was 1.7 delta. Unilateral surgery for XT with convergence weakness biased to medial rectus strengthening and geared to near deviation can successfully collapse the near-distance differences while satisfactorily aligning both distance and near fixation. This surgery has low risk of creating long-term postoperative esodeviations at distance.
authors.affiliation: Department of Ophthalmology, Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: S P
authors.initials: SP
authors.lastname: Kraft
authors.forename: A V
authors.initials: AV
authors.lastname: Levin
authors.forename: R W
authors.initials: RW
authors.lastname: Enzenauer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003290:Convergence, Ocular; D005099:Exotropia / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009801:Oculomotor Muscles / Q000601:surgery*; D011446:Prospective Studies; D014792:Visual Acuity