Evaluation of Early Corneal Endothelial Cell Loss in Bimanual Microincision Cataract Surgery (MICS) in Comparison with Standard Phacoemulsification

Abstract

PURPOSE: To analyze early corneal endothelial cell loss due to microincision cataract surgery (MICS) in comparison with standard phacoemulsification through the temporal clear corneal incision. METHODS: The examined group consisted of a nonrandomized, consecutive prospective series of 20 eyes of 20 patients who underwent uneventful microincision cataract surgery. Twenty eyes of 20 patients who underwent standard phacoemulsification with foldable intraocular lens (IOL) implantation served as a reference group. Patients with corneal disorders, contact lens wear, previous intraocular surgery, and a history of ocular trauma were excluded from the study. Patients were examined preoperatively and 10 days postoperatively. The following items were evaluated in this study: corneal endothelial cell density, intraoperative phaco power, effective phaco time, as well as pre- and postoperative visual acuity. Corneal endothelial cell counts were done in the central part of the cornea using a non-contact Topcon SP 2000P specular microscope before and 10 days after the surgery. The measurements were performed in a semiautomated, masked manner. Statistical analysis was done using nonparametric tests (Wilcoxon signed-ranks test and Mann-Whitney U test). RESULTS: All patients in the study underwent uneventful surgery. Best-corrected visual acuity (BCVA) examined 10 days postoperatively in the MICS group was 0.94+/-0.094, whereas in the standard phacoemulsification group it was 0.90+/-0.094. There was no significant difference between BCVA in the two groups (Mann Whitney U two-tailed test: p>0.05). In both groups there was a significant decrease in postoperative endothelial cell densities (ECDs) when compared to preoperative values. Mean postoperative ECDs were 2235+/-418 cells/mm2 in the MICS group and 2079+/-399 cells/mm2 in the standard phacoemulsification group; the difference was not statistically significant (Mann-Whitney U test: p>0.05). Patients in the MICS group lost an average of 9.5% of cells, whereas patients after standard phacoemulsification lost about 7.6% of cells. This difference was statistically insignificant. CONCLUSIONS: Microincision cataract surgery induced corneal endothelial cell loss similar to a standard phacoemulsification and allowed excellent visual results in this series of patients. These results support the use of MICS technique for cataract surgery.