Morphometric features of corneal epithelial basal cells, and their relationship with corneal nerve pathology and clinical factors in patients with type 2 diabetes

AIMS/INTRODUCTION We compared the morphometric features of corneal epithelial basal cells between patients with type 2 diabetes mellitus and healthy controls, and analyzed the relationship of these features with corneal nerve fiber pathology and clinical factors in the patients. MATERIALS AND METHODS Corneal epithelial basal cells and corneal nerve fibers were visualized by corneal confocal microscopy in 75 patients with type 2 diabetes and 42 age-matched controls. Density, area and area variability of corneal epithelial basal cells, as well as the width of the intercellular space between neighboring cells, were evaluated for both groups. RESULTS Patients showed decreased density (P < 0.02) and area (P < 0.0001), larger area variability (P < 0.0001) and a wider intercellular space (P < 0.0001) compared with controls. Density correlated inversely with area (P < 0.0001), width of intercellular space (P < 0.03) and beading frequency (P < 0.03), whereas it correlated directly with prothrombin time (P < 0.002) and activated partial thromboplastin time (P < 0.03). Area correlated inversely with duration of diabetes (P < 0.05) and coefficient of variation of area (P < 0.01), whereas it correlated directly with beading frequency (P < 0.05). Area variability correlated inversely with area (P < 0.01) and prothrombin time (P < 0.01), whereas it correlated directly with fibrinogen level (P < 0.0001). CONCLUSIONS Type 2 diabetes induces morphometric changes in corneal epithelial basal cells; this seems to be related to the morbid period of diabetes, beading frequency of corneal nerve fibers and blood coagulation state.