To document and compare the clinical results of symmetrical rectus muscle recession and asymmetrical rectus muscle recession in intermittent exotropia.

The medical records of 27 patients who had symmetric bilateral rectus recession and 24 patients who had asymmetric bilateral rectus recession for intermittent exotropia with at least six months of postoperative follow-up from March 2004 to March 2007 were reviewed retrospectively. The authors performed a recession of 2 mm or greater in the deviating eye than in the fixing eye.

The mean age was 7.14±4.23 (range 3 to 15) years for symmetric bilateral rectus recession and 7.33±4.01 (range 3 to 14) years for asymmetric bilateral rectus recession. The mean follow-up was 11.83±5.74 (range 6 to 26) months in the symmetric bilateral rectus recession group and 11.14±5.05 (range 6 to 30) months in the asymmetric bilateral rectus recession group. The mean preoperative angle deviations were 27.5±4.8 prism diopter (PD) (range 30 to 40PD) and 27.3±4.6PD (range 20 to 40PD) in each group. The outcome of final follow-up (postoperative 24 months) was favorable in both groups, and slightly more successful in the asymmetric bilateral recession group but not a statistically significant amount (75.5% in the symmetric bilateral recession group and 81.2% in the asymmetric bilateral recession group).

The present study suggests that there are no significant differences at postoperative 24 months between symmetric bilateral recession and asymmetric bilateral recession in intermittent exotropia having a fixing and a deviating eye.