Abstract
Purpose: :
Corneal diabetic neuropathy (CDN) is a hallmark of peripheral diabetic neuropathy. In this study, we investigate corneal subbasal nerve plexus changes in CDN using corneal confocal microscopy .
Methods: :
30 consecutive diabetic patients affected in both eyes by CDN ( subasal plexus nerve changes) were investigated and followed using corneal confocal microscopy (Confoscan4, Nidek, Japan). A new validated technique for subasal nerve plexus detection and examination was applied. Corneal confocal microscopy parameters for nerve changes were: number and density of nerve fibers, nerve tortuosity and branching, number of nerve beadings. Two masked examiners evaluated and quantified corneal confocal microscopy images.
Results: :
Corneal confocal microscopy allowed in all cases a quantitative analysis of subbasal nerve plexus. Intra and inter-examiner agreement for confocal microscopy images were almost perfect (k= 0.95 and 0.92 , respectively). Significant Increase of nerve beadings (p <0.005) and reduction in nerve tortuosity ( p<0.004) were the distinctive parameters of nerve regeneration. Increase of nerves density and fibers was a late phaenomenon.
Conclusions: :
These results show that corneal confocal microscopy is the key diagnostic technique in evaluating and monitoring CDN. Quantification of corneal subbasal nerve plexus parameters allows a correct, reproducible and objective, in vivo, non invasive approach to CDN, allowing to characterize peripheral diabetic neuropathay, a potentially highly diasbling complication of diabetes.
Keywords: diabetes • cornea: clinical science • neuroprotection