Corneal Biomechanical Properties in Floppy Eyelid Syndrome

Purpose: To determine corneal biomechanical properties in patients with floppy eyelid syndrome (FES) and to compare them with eyes of controls. Methods: This case-control study included 208 eyes (72 eyes with FES and 136 without FES) of 107 patients (37 patients with FES and 70 without FES). Patients underwent a complete clinical eye examination that included corneal biomechanical evaluation carried out with the Reichert Ocular Response Analyzer. Results: Corneal hysteresis (CH), corneal resistance factor (CRF), central corneal thickness (CCT), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were evaluated. Mean CH was significantly lower in patients with FES than in those without FES (9.51 +/- 1.56 vs. 11.66 +/- 9.11; P < 0.001). These results remained statistically significant after adjusting for age and apnea-hypoapnea index (AHI) (P = 0.028). Mean CRF was 10.02 +/- 2.08 in the group of patients with FES and 11.21 +/- 5.36 in the group of patients without FES (P = 0.001). Mean IOPcc was 17.7 +/- 4.8 in patients with FES and 16.3 +/- 4.4 in those without FES (P = 0.036). After adjusting for age and AHI, these differences in CRF and IOPcc were not statistically significant (P = 0.26 and P = 0.87, respectively). No statistically significant difference was found between patients with and without FES for Goldmann-correlated intraocular pressure or CCT. Conclusions: Patients with FES had statistically lower CH values. Our findings suggest that corneal biomechanical properties could be changed in patients with FES, reflecting additional structural changes in FES.