Intraocular Pressure Change With Eye Positions Before and After Orbital Decompression for Thyroid Eye Disease

Abstract

To examine intraocular pressure (IOP) changes in primary and upward gazes before and after orbital decompression in patients with thyroid eye disease. Seventy-eight orbits of 40 patients who underwent orbital decompression between June 2010 and September 2012 were retrospectively reviewed. Subjects were divided in 2 groups according to the number of orbital walls removed: deep lateral orbital wall decompression group (Group A) or balanced decompression group (Group B). IOP was measured using Goldmann applanation tonometry in primary gaze and a 20° upward gaze before and 3 months after surgery. Preoperative IOP in upward gaze (18.7 mm Hg) was higher than in primary gaze (15.7 mm Hg, p < 0.001). Postoperative IOP reduction in upward gaze (3.8 mm Hg) was greater than in primary gaze (1.7 mm Hg, p < 0.001). Although the overall postoperative IOP in upward gaze (14.9 mm Hg) remained higher than in primary gaze (14.0 mm Hg, p = 0.038), the gaze-related IOP demonstrated no significant difference in all subgroups (Group A, p = 0.091; Group B, p = 0.332). IOP in upward gaze was higher prior to orbital decompression, but reduction was greater postoperatively and approximated the IOP in primary gaze.