Corneal endothelial alterations in patients with diabetic macular edema

Abstract

Background/Aim: Diabetic macular edema (DME) is the main cause of visual loss in diabetic patients. Although it is known that diabetes mellitus could affect all corneal layers, there is no data about the morphological and quantitative changes of corneal endothelium in patients with DME. The aim of this study is to evaluate the corneal endothelial cell density (CD), morphology and central corneal thickness (CCT) in patients with DME. Methods: This retrospective study included 47 diabetic patients (79 eyes) with DME, 48 diabetic patients (93 eyes) without DME, and 46 nondiabetic subjects (74 eyes). Diagnosis of DME was based on fundoscopy and optical coherence tomography imaging. The corneal endothelial structure and CCT were evaluated using non-contact specular microscopy. The endothelial CD (cells/mm2), coefficient variation of cell area (CV), percentage of hexagonality (HEX) and CCT of the three subgroups were compared. Results: The mean age of participants was 59.8 (8.3) years. There was no significant difference in terms of age between diabetic patients and control subjects (P=0.761). In the diabetic subgroups, HbA1c levels and the number of patients receiving insulin were similar (P=0.962, P=0.082, respectively), but the mean duration of diabetes was significantly longer in the DME subgroup than in the no-DME subgroup (P=0.015). Patients in the DME subgroup did not differ from the patients in the no-DME and control subgroups with regards to endothelial CD and CCT. However, there was a statistically significant decrease in HEX and increase in CV in patients with DME (P=0.012, P=0.012, respectively). Conclusion: Patients with DME were found to have higher rates of polymegathism and polymorphism although there were no significant changes in corneal endothelial CD and CCT. These alterations may be the first signs of early corneal damage in patients with DME.

Keywords

• corneal endothelium
• diabetic macular edema
• polymegathism
• polymorphism
• specular microscopy

Kaynakça

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