Postoperative Corneal Swelling Correlates Strongly to Corneal Endothelial Cell Loss After Phacoemulsification Cataract Surgery

Abstract

To evaluate postoperative corneal swelling as a predictor of corneal endothelial cell loss after phacoemulsification cataract surgery. Prospective observational case series. Thirty patients planned for routine phacoemulsification cataract surgery were included. Ultrasonic pachymetry and specular microscope endothelial photography of the central and nasal portions of the cornea and Orbscan II slit-scan tomography were performed preoperatively and the day after surgery. The 30 patients were selected from 41 patients based on their increase in central corneal thickness: the first 10 cases with a <5% increase, the first 10 with a 6% to 20% increase, and the first 10 with a > or =20% increase. The same measurements were repeated after 1, 2, and 3 months. The primary outcome measures were corneal endothelial cell loss and increase in pachymetry. Several other parameters were also registered, including age, degree of cataract, visual acuity, phacoemulsification time and energy, total operation time, and the amount of infusion fluid used. The central corneal swelling at postoperative day 1 was strongly correlated with the central corneal endothelial cell loss at 3 months (R(2) = 0.785, P < .001). In this series, with large variations in the corneal swelling at the first postoperative day, the degree of permanent corneal endothelial damage was reflected in the degree of early postoperative corneal swelling. Measuring the difference in pachymetry at postoperative day 1 is a useful way to assess the effects on the corneal endothelium exerted by the phacoemulsification procedure.