The Effect of Teprotumumab on Eyelid Position in Patients with Thyroid Eye Disease

Teprotumumab has been shown to improve proptosis and clinical activity scores (CAS) in patients with thyroid eye disease, but little has been published regarding its effects on eyelid retraction. The purpose of this work was to evaluate changes in eyelid position in thyroid eye disease patients after teprotumumab. Eight patients completed eight cycles of teprotumumab. Data collected included exophthalmometry; clinical activity scores; margin reflex distance (MRD) 1; MRD2; and pre-, during, and posttreatment photographs. ImageJ analysis was also used to evaluate eyelid position in photographs. Proptosis significantly improved in 15 of 16 orbits [mean 4.75 ± 2.07 mm reduction (P = 0.0001) in study orbits and mean 3.00 ± 2.14 mm reduction (P = 0.0048) in nonstudy orbits]. CAS was significantly reduced (pretreatment mean 4.88 mm and posttreatment mean 1.88 mm, P = 0.006). MRD1 decreased in 11 of 16 orbits and increased in five orbits (P = 0.18 in study orbits and P = 0.22 in nonstudy orbits). MRD2 decreased in six of 16 orbits and increased in eight orbits (P = 0.49 in study orbits and P = 0.43 in nonstudy orbits). Patients exhibited variable changes in eyelid position with teprotumumab. There was a statistically insignificant decrease in MRD1 after teprotumumab. Proptosis reduction led to unpredictable changes in MRD1 and MRD2. Severity of eyelid retraction did not correlate with clinical activity score response to teprotumumab. There are inherent difficulties in evaluating eyelid position in thyroid eye disease, which may necessitate a paradigm shift in how patients are examined, measured, and photographed.