ENDOTHELIAL-CELL DENSITY AND CONTACT LENS-INDUCED CORNEAL SWELLING

Purpose. To determine the relationships among endothelial morphometric variables and contact lens-induced corneal swelling in a homogeneous sample of adapted contact-lens wearers. Methods. Fifteen male subjects ranging in age from 20 to 40 years, all adapted to daily wear of hydr ogel lenses, wore uniform-thickness lenses (Dk/L = 5.78) under unilate rally patched eyes for 4 h. Unpatched fellow eyes served as controls. Central corneal thickness was measured with an optical pachometer. Cen tral endothelial images were obtained with a Topcon SP-1000 Specular M icroscope and analyzed by the Topcon IMAGEnet processing system. Thick ness and morphometric data were collected on test and control eyes bef ore and after the patching sessions. Results, A strong correlation (r = -0.795; p < 0.001) was found between central corneal swelling and en dothelial-cell density. Correlations between swelling and the coeffici ent of variation in cell area (r = 0.502; p < 0.06) and between swelli ng and the percentage of six-sided cells (r = -0.200; p < 0.48) were n ot significant. Correlations among the morphometric variables were not significant. Differences in the morphometric variables between test a nd control eyes were not significant before or immediately after the p atching sessions. Conclusion. Endothelial-cell density is useful in ex plaining differences in corneal-swelling responses to closed-eye conta ct-lens wear among adapted wearers, whereas morphometric variables bas ed on cell-size variability and shape are not.