Effect of inferior oblique recession in strabismus sursoadductorius.

UNLABELLED The aim of this retrospective study was a quantitative analysis of the effect of graded inferior oblique recessions (8 mm, 10 mm or maximal) in strabismus sursoadductorius. METHOD 234 patients (2-81 years of age) with unilateral strabismus sursoadductorius and stereopsis were operated between 1990 and 1999. Maximal recession (14.6 mm) included an anteroposition to the lateral aspect of the insertion of the inferior rectus. Before and three months after the operation, horizontal and vertical deviations (VD) were assessed by cover testing in five positions of gaze. In 121 patients, additional subjective quantitative assessment, including cyclodeviation measurement, was carried out with Harms' tangent screen. RESULTS The mean effect of the operation on VD in 25 degrees adduction increased from 6 degrees with 8 mm recession to 10 degrees with maximal recession. It was related more to the amount of preoperative VD in adduction than to the amount of recession. One patient had a limitation of elevation with a hypotropia of >4 degrees, 7% needed further surgery because of undercorrection. DISCUSSION Maximal recession of the inferior oblique muscle is a suitable procedure even in patients with marked strabismus sursoadductorius. The rate of functional undercorrection is low and there is no risk from general anesthesia or significant postoperative limitation of elevation.