Two-muscle surgery for congenital esotropia: Rate of reoperation in patients with small versus large angles of deviation

Introduction: Standard surgical treatment of congenital esotropia (CET) in patients with preoperative angles of deviation measuring less than or equal to 50 PD is well defined. However, there is controversy over the managemen t of larger angles of esotropia. Some surgeons prefer to operate on 3 or 4 horizontal rectus muscles, while others prefer to perform large recessions of the medial rectus muscles alone. The purpose of this study was to compar e the rate of reoperation after bilateral medial rectus muscle recession of smaller angle (less than or equal to 50 PD) CET with the rate of reoperati on after surgery for larger angle (>50 PD) GET. Methods: Medical records of 102 patients who underwent bilateral medial rectus muscle recessions betwe en January 1991 and December 1997 were reviewed. Patients were excluded if neurologic abnormalities or developmental delays were documented before the operation, if major structural abnormalities of the eye were present, or i f less than 1-month follow-up after surgery was documented. The remaining 5 6 patients were assigned to either the larger angle (>50 PD) or smaller ang le (less than or equal to 50 PD) group, based on the magnitude of their pre operative esotropia. Rates of reoperation for residual GET, for consecutive exotropia or dissociated horizontal deviation, or for dissociated vertical deviation with or without oblique muscle dysfunction were determined for e ach group. Results: Forty of 56 patients (71%) were assigned to the smaller angle group and 16 of 56 patients (29%) to the larger angle group. In the larger angle group, 4 patients (25%) underwent surgery for residual esotrop ia. In the smaller angle group, 8 patients (19%) underwent surgery for resi dual esotropia, 8 (19%) underwent surgery for consecutive exotropia or diss ociated horizontal deviation, and 8 (19%) underwent surgery for dissociated vertical deviation or oblique muscle dysfunction. conclusion: The success rate for ocular realignment in patients with CET by using bilateral medial rectus muscle recession did not appear to diminish when applied to deviatio ns greater than 50 PD as compared with smaller angle deviations. Surgery on 3 or 4 horizontal rectus muscles may be unnecessary in the treatment of pa tients with very large angles of CET.