Delayed consecutive exotropia following 7-millimeter bilateral medial rectus recession for congenital esotropia

The rate of delayed consecutive exotropia after bilateral 7-millimeter medial rectus recession for large angle congenital esotropia in 88 patients was 27% (24/88), larger than previously reported. The rate was 38% (8/21) in infants having surgery prior to 7 months of age, 20% (10/49) in infants undergoing surgery at 7 to 12 months of age, and 33% (6/18) in patients undergoing surgery at 13 months of age or later. The onset of consecutive exotropia averaged 26.8 months postoperatively, allowing a long period of good alignment for binocular vision to develop before exotropia surgery was required. Physicians and parents should be aware that delayed consecutive exotropia may develop several years postoperatively. Since delayed consecutive exotropia may be characteristic of the 7-millimeter recession procedure or characteristic of all patients who have had surgery for congenital esotropia, a prospective long-term study to compare the 7- millimeter procedure with the three- and four-muscle procedure would be helpful.