Corneal neuropathy: An overlooked biomarker for dry eye in type 2 diabetes

The article by Han and associates highlights a frequently neglected consequence of type 2 diabetes mellitus (T2D): Dry eye disease associated with corneal neuropathy. Their findings indicate that patients with T2D exacerbated by dry eye disease exhibit substantial decreases in corneal nerve density, length, and count, accompanied by heightened tortuosity, all of which correlate strongly with clinical severity scores. This study contributes to the expanding literature that regards ocular surface disease not only as a secondary effect of systemic illness but also as a direct indication of neurovascular and metabolic impairment. Clinically, these findings underscore the importance of regularly evaluating dry eye in patients with T2D, extending beyond diabetic retinopathy, and incorporating ocular surface assessments into comprehensive diabetes management. This study demonstrates that the diabetic eye exhibits both tear film instability and corneal neurodegeneration, thereby expanding our understanding of diabetic eye disease and emphasizing the need for multidisciplinary care to preserve vision and improve quality of life.