Posterior tenotomy of the superior oblique at the scleral insertion for A-pattern deviations.

A posterior (two-thirds) tenotomy of the superior oblique at the scleral insertion spares the anterior fibers whose action is primarily torsional and can avoid some complications such as cyclovertical diplopia or torticollis, which may be induced by a superior oblique tenotomy or a recession for A-pattern deviations associated with superior oblique overaction (SOOA). A retrospective review was performed of 11 cases with A-pattern, aged 5 to 51 years, who underwent the posterior tenotomy. The average preoperative A-pattern was 18.3 prism diopters and the posterior tenotomy resulted in 16.3 prism diopters of reduction in the A-pattern. There was a good coefficient of correlation between the preoperative amount of A-pattern and the obtained reduction in it (P < 0.001). SOOA was graded on a 9-point system. The average SOOA score of our cases was reduced from +2.77 to +0.77 after the surgery. None of the cases showed worsening of stereoacuity or cyclodeviation. The posterior tenotomy is a simple and effective procedure to correct mild to moderate A-pattern deviations with SOOA.