Corneal Biomechanical Properties in Rheumatoid Arthritis

Purpose: To investigate the variations in biomechanical properties of the cornea in rheumatoid arthritis (RA) patients. Methods: A total of 53 RA patients, and 25 healthy individuals (control group) were enrolled. Rheumatoid arthritis patients were classified as in active phase (group 1; n=24) or in remission phase (group 2; n=29). Corneal biomechanical parameters including corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with the Reichert Ocular Response Analyzer. Topographical measurements, including central corneal thickness (CCT), anterior chamber depth, iridocorneal angle, and corneal volume were measured using a Sirius corneal topographer. Results: The mean CH was 9.431.17 mm Hg in group 1, 9.42 +/- 1.84 mm Hg in group 2, and 10.47 +/- 1.68 mm Hg in the control group (P=0.03). The mean IOPcc was 17.85 +/- 3.2 mm Hg in group 1, 17.95 +/- 3.49 mm Hg in group 2, and 15.36 +/- 3.11 mm Hg in the control group (P=0.008). The CH showed a significant positive correlation with CRF (P=0.000, r=0.809) and CCT (P=0.000, r=0.461), and a significant negative correlation with IOPcc (P=0.000, r=-0.469). Conclusions: Decrease in the mean CH measurements indicates that ultrastructural changes in the cornea may occur in the active phase, and these changes persist in the remission period. In addition, IOPcc is significantly affected by the corneal biomechanical properties. In RA patients, it is important to control the corneal parameters and IOP measurements against the irreversible changes on the optic nerve.