Long-term endothelial cell loss following phacoemulsification through a temporal clear corneal incision

PURPOSE: To evaluate central endothelial cell loss (ECL) following clear corneal cataract surgery using two different incision sizes and the effect of ultrasound time (UST) and power on postoperative ECL and various cell parameters. METHODS: Fifty-eight patients had phacoemulsification through temporal, two-step clear corneal tunnel incisions. In Group A (n = 28), a one-piece, plate-haptic foldable silicone intraocular lens (IOL) was implanted through a 3.5 mm sutureless incision. In Group B (n = 30), a poly(methyl methacrylate) IOL was implanted through a 5.0 mm incision with one radial suture. The central endothelial cell counts were recorded preoperatively and postoperatively at 2 to 5 days, after 6 months, and after 1 year. Color-coded, computer-assisted specular microscopy was used for special cell analysis after 1 year. RESULTS: Collective data showed an ECL of 7.9 +/- 4.1% (mean +/- standard deviation) at 2 to 5 days postoperatively, 6.7 +/- 2.9% after 6 months, and 7.3 +/- 3.3% after 1 year. A direct linear relationship was found between ECL and UST and power: ECL increased as UST and power increased. After 1 year, ECL in Group A was 4.2% with UST 11/2 to 21/2 min, and 9.6% with UST > 21/2 to 31/2 min; in Group B it was 6.0%, 7.5%, and 11.4%, respectively. Specular microscopy showed normal, age-related cell parameters 1 year postoperatively. CONCLUSIONS: Phacoemulsification with 3.5 mm clear corneal incisions produced slightly less ECL (6.7%) than phacoemulsification with 5.0 mm incisions (7.9%). Total ECL of 7.3% at 1 year postoperatively compared favorably with ECL rates of other cataract extraction methods.