Changes in ocular biomechanics after treatment for active Graves' orbitopathy

Abstract

Purpose To evaluate the changes in ocular biomechanical properties in active moderate-to-severe Graves' orbitopathy (GO) after intravenous glucocorticoids (IVGCs), and to clarify correlations between clinical findings and ocular biomechanical properties. Methods A prospective study. A total of 20 consecutive GO patients and 20 age- and sex-matched healthy control subjects were included. GO was diagnosed on the basis of the recommendation by the European Group on Graves' Orbitopathy (EUGOGO), and disease activity was assessed by the clinical activity score (CAS). Patients were assigned to receive once weekly IVGCs (0.5 g, then 0.25 g, 6 weeks each). All participants received a full ophthalmic examination and biomechanical evaluation was performed with dynamic Scheimpflug analyzer (Corvis ST) at baseline and 12th weeks after therapy. Results The biomechanically corrected intraocular pressure (bIOP) in GO patients was significantly higher than that in healthy subjects. In contrast, the whole eye movement (WEM) in GO patients was significantly lower than in healthy subjects after adjusting for bIOP. The CAS, NOSPECS score, and exophthalmos were significantly positively correlated with the bIOP and negatively correlated with the WEM after adjusting for bIOP, CCT and age. The WEM significantly increased, whereas bIOP significantly decreased after IVGCs (P < 0.001,P = 0.001 respectively). The overall response rate at the 12th week was 85% (17 of 20). Conclusions The changes of ocular biomechanical properties measured by Corvis ST were an objective indicator of inflammatory activity and severity of GO. Combining CAS and ocular biomechanical properties could better evaluate the therapeutic outcome of active moderate-to-severe GO.