[Recession of both horizontal rectus muscles in Duane Retraction Syndrome with significant globe retraction]

To evaluate the effect of Recession of both horizontal rectus muscles in Duane Retraction Syndrome with significant globe retraction.

Sixteen cases with DRS were summarized retrospectively. All patients had undergone surgery with recession of both horizontal rectus muscles. All clinical records, including sex, age, types of DRS, clinical features, surgical methods and clinical outcomes were analyzed. All patients were followed up for 3 months to 1 year.

Fifteen cases had only monocular involvement while one had both eyes. The number of type I DRS was 3 cases, 1 case was esotropia while others were orthotropic in primary position. Type III DRS was observed 13 cases. Esotropia was seen in 6 cases (7 eyes), exotropia of 1 cases and orthotropic in primary position of 6 cases. 10 cases exhibited marked face turn. An upshoot or downshoot and variable severity of retraction of globe were found in all patients on attempt adduction of the affected eye. All patients had undergone surgery with recession of both horizontal rectus muscles. The medical rectus muscles were recessed from 5 mm to 7 mm and lateral rectus muscles 3 mm to 9 mm simultaneously, which was based on the amount of primary position deviation. Among these 2 cases were combined with Y-splitting of lateral rectus muscle. After surgery, all patients were orthotropic in primary position. Their symptom of unacceptable abnormal head position, significant globe retraction, noticeable narrowing of the palpebral fissure and significant upshoot or downshoot were ameliorated or disappeared. Especially the recession of lateral rectus muscle in addition to Y-splitting combining with the simultaneous medial rectus recession resulted in further amelioration of globe retraction in addition to upshoot and downshoot.

Recession of both horizontal rectus muscles is effective in the treatment of significant globe retraction in Duane syndrome. Type III DRS with significant globe retraction but has no marked deviation and face turn can adopt this method to ameliorate their aspect. The method of lateral rectus muscle in addition to Y-splitting plays an important role in the treatment of upshoot and downshoot.