Changes in corneal thickness after manual SICS greater in diabetic eyes

Cornea. 2011;30(4):424-428.

Diabetic patients had greater endothelial cell loss and change in central corneal thickness after manual small incision cataract surgery compared to healthy controls, according to a study conducted in India.

"Patients with diabetes have been documented to have thicker corneas," the study authors said. "They may also have a low endothelial reserve, making the endothelium more prone to stress-related injuries like ocular surgeries, despite a normal endothelial count."

The prospective cohort study included 153 eyes of 153 patients with type 2 diabetes and 163 eyes of 163 age-matched, nondiabetic controls. Average patient age was 61 years in the diabetic group and 60 years in the nondiabetic group.

Investigators used specular microscopy and ultrasound pachymetry to assess endothelial cell count and central corneal thickness (CCT) preoperatively and at 1 week, 6 weeks and 3 months postoperatively.

Endothelial cell density decreased 9.26% at 6 weeks and 19.24% at 3 months in diabetic eyes, and 7.67% at 6 weeks and 16.58% at 3 months in controls. Between 6 weeks and 3 months, cell density decreased 13.58% in diabetic eyes and 7.06% in controls; the decrease was statistically significant (P < .023).

Central corneal thickness increased in both groups until 2 weeks after surgery, decreased at 6 weeks and decreased further at 3 months. The change in CCT between 2 weeks and 6 weeks was statistically significant in the diabetic group (P = .045). At 6 weeks, CCT was appreciably higher in the diabetic group than in the control group (P < .25), the authors reported.