Corneal Endothelial Cell Changes Associated with Cataract Surgery in Patients with Type 2 Diabetes Mellitus

Purpose: To investigate the corneal endothelial cell density and morphology in patients with and without diabetes after phacoemulsification with intraocular lens implantation.

Methods: A clinical prospective study including 30 patients with type 2 diabetes and 30 control patients without diabetes scheduled to undergo cataract surgery. No difference in preoperative age was observed between the 2 groups (P = 0.90). Sample size was based on a power calculation (power 0.90; P = 0.05). The patients without diabetes had a casual blood glucose test performed to disclose undetected diabetes. The patients with diabetes had a serum glycosylated hemoglobin (HbA1c) test performed to reveal the glycemic control. The endothelial cell density, variation in endothelial cell size (CV), percentage of hexagonal cells, and central corneal thickness (CCT) were recorded at baseline and at 3 months postoperatively.

Results: The mean decrease in endothelial cell density at 3 months in the diabetic group was 154 cells per square millimeter (6.2%) and 42 cells per square millimeter (1.4%) in the control group. The difference in cell loss between the 2 groups was significant (P = 0.04). A significant decrease in the percentage of hexagonal cells was also seen in the diabetic group (P = 0.01). There was no statistically significant change in CV or CCT. Visual acuity increased significantly and equally in the 2 groups.

Conclusions: The present study reveals a significantly greater loss of corneal endothelial cells in a diabetic group under good glycemic control, compared with nondiabetic group 3 months after phacoemulsification. The morphological changes in the endothelial cells in patients with well-controlled diabetes were not reflected in impaired function as judged by CCT.