The relation between corneal autofluorescence, endothelial cell count and severity of the diabetic retinopathy.

We measured the corneal autofluorescence in groups with different levels of diabetic retinopathy severity (72 eyes of 46 patients) and in age-matched non-diabetic controls (34 eyes of 24 controls). We also estimated the corneal endothelium cell count and pachymetry with a contact specular microscope. For the controls, mean corneal autofluorescence was 8.8 ng equivalents fluorescein/ml (SD 0.3). Results showed increased autofluorescence of the cornea in diabetic patients (mean 17.9 ng equivalents fluorescein/ml, SD 4.2), related to the duration of diabetes (P < 0.05) and to the severity of diabetic retinopathy (P < 0.0001). Corneal endothelial cell count results showed no statistically significant relation to corneal autofluorescence (P < 0.6), indicating that the increased autofluorescence cannot be attributed to a change in corneal cell density.