Corneal Specular Microscopy Changes in Type II Diabetes Mellitus

Abstract

ABSTRACT:BACKGROUND: Corneal endothelial cells count and shape are vital in keeping corneal transparency with normal vision. Diabetes mellitus is associated with significant changes in the corneal endothelium. OBJECTIVE: To compare corneal endothelial structure and central corneal thickness (CCT) between type II diabetics and non-diabetic control patients.METHODS: Specular microscopy was used to measure central corneal thickness (CCT), average size of endothelial cells, standard deviation of cell size and coefficient of variation in cell area (CV), endothelial cell density, as well as hexagonality of 260 eyes from 260 patients ( 130 eyes from type II diabetic patients and 130 eyes from non diabetic controls).RESULTS: The diabetic corneas have a significant increase in average size of endothelial cells (410.4 ± 89.6 µm² vs. 382.3 ± 83.4 µm²)(p <0.05 ), standard deviation of cell size (152.2 ± 38.0 µm² vs. 128.7 ± 19.5 µm²)(p <0.05) and coefficient of variation (CV) (38.3 % ± 5.4 % vs. 33.4 % ± 4.4%)(p<0.05). and a significant decrease of endothelial cell density (2570.7 ± 563.1 cells / mm² vs. 2704.1 ± 572.5 cells / mm²)(p <0.05) and hexagonality (48.3 ± 17.1% vs. 56.5% ±15.6%)(p<0.05). There was no significant difference in central corneal thickness(CCT) (516.3 ± 63.4 µm vs. 512.8 ± 61.7µm )(p >0.05). CONCLUSION: Type II diabetes associated with a significant changes in the corneal endothelium including, reduction of endothelial cell density, increased variation of cells shape (pleomorphism) and increased variation of cells area (polymegathism). There was no significant changes of central corneal thickness (CCT).