Effect of Inferior Rectus Muscle Recession on Intraocular Pressure in Thyroid Eye Disease Patients with Ocular Hypertension

● BACKGROUND: To study the effect of inferior rectus muscle recession on intraocular pressure (IOP) in thyroid eye disease (TED) patients with ocular hypertension.● METHODS: This is a retrospective, observational case series. The medical records of patients with ocular hypertension, despite use of antiglaucoma medications, and restrictive myopathy secondary to thyroid eye disease who underwent inferior rectus muscle recession from January 1, 2016 through December 31, 2021 were reviewed and analyzed retrospectively. Seven eyes from six patients met the criteria and were included in this study. All patients were examined at Taichung Veterans General Hospital, a tertiary referral center. The main outcome measure was IOP readings obtained before and after surgery in both primary gaze (hypotropia) and upgaze (or attempted upgaze).● RESULTS: A statistically significant decrease in IOP in primary gaze (hypotropia) and upgaze (or attempted upgaze) was noted after inferior rectus muscle recession. The median IOP before surgery was 24.0 mmHg in primary gaze and 30.5 mmHg in upgaze. After strabismus surgery, the median IOP after one week was 18.0 mm Hg in primary gaze and 20.0 mmHg in upgaze; the median IOP one month after surgery was 15.0 mmHg in primary gaze and 16.5 mmHg in upgaze; the median IOP 3 months after surgery was 12.5 mmHg in primary gaze and 13.5 mmHg in upgaze; the median IOP 12 months after surgery was 15.5 mmHg in primary gaze (overall P = .001) and 17.0 mmHg in upgaze (overall P = .001). All eyes were treated with three to four antiglaucoma medications before the surgery. Four eyes discontinued all preoperative medications within 3 months after the surgery. The other three eyes kept using preoperative medications.● CONCLUSIONS: Inferior rectus muscle recession resulted in a significant and sustained reduction in IOP in patients with ocular hypertension and restrictive myopathy secondary to thyroid eye disease.