PURPOSE: To describe a surgical approach to selectively weaken the anterior cyclotorsional fibers of the superior oblique muscle in subjects with incyclotorsion. METHODS: Retrospective review of five consecutive subjects with diplopia and incyclotorsion who underwent unilateral tenectomy of the anterior fibers of the superior oblique alone or in combination with surgery on another horizontal or vertical rectus muscle. RESULTS: The mean preoperative incyclotorsion was 7.2 degrees . The mean postoperative follow-up was 4 months. Superior oblique anterior tenectomy corrected 5.2 degrees of incyclotorsion. No patient developed pattern strabismus induced vertical deviation or diplopia due to excyclotorsion postoperatively. The mean incyclotorsion present at the last follow-up was 2 degrees . Torsional diplopia persisted in two (40%) subjects. CONCLUSIONS: Anterior tenectomy of the superior oblique tendon at the insertion may be helpful in subjects with incyclotorsion who have no vertical deviation in the primary position or in whom there is risk of pattern anisotropia or anterior segment ischemia by operating upon vertical rectus muscles.