Improvement of horizontal excursion and abduction by vertical muscle transposition in patients with Duane's retraction syndrome type I.

PURPOSE

To measure the change in horizontal excursion and improvement of abduction in Duane's retraction syndrome type I after transposition of both vertical rectus muscles and recession of the medial rectus muscle in the affected eye.

PATIENTS AND METHODS

This was a retrospective study of patients undergoing surgery for Duane's retraction syndrome type I. Thirty-six patients were treated by transposition of both vertical rectus muscles in combination with medial rectus recession of the affected eye. Head posture, binocular vision, abduction and adduction of the affected eye, and angle of strabismus were measured before and after surgery.

RESULTS

After surgery, abduction improved by 15.9 degrees +/- 8.1 degrees (mean +/- standard deviation) and adduction decreased by 5.9 degrees +/- 7.2 degrees. Horizontal excursion improved from 43.1 degrees +/- 8.8 degrees to 53.1 degrees +/- 11.8 degrees. One patient had signs of anterior segment ischemia (ie, enlarged, fixed oval pupil and cells in the anterior chamber), which disappeared after local steroid eye drops were administered.

CONCLUSIONS

Surgery enlarges the range of horizontal excursion of the affected eye and causes only a limited decrease in adduction. One patient developed transient anterior segment ischemia. Vertical muscle transposition combined with medial rectus recession is an effective procedure to improve horizontal excursion and abduction in patients with Duane's retraction syndrome type I.