Assessing the sub-basal nerve plexus of the living healthy human cornea by in vivo confocal microscopy

The purpose of the study was to perform quantitative analysis of the sub-basal epithelial nerve plexus of healthy, living human cornea, using real time in vivo confocal microscopy and the analySIS software system. The study was based on in vivo confocal microstructural analysis of 50 eyes of 50 subjects, divided into two age groups: group 1 (n = 25) 25 +/- 5 years of age, and group 2 (n = 25) 70 +/- 5 years of age. All subjects exhibited clinically healthy corneas. The overall nerve density was 632.35 +/- 287.57 mum/mm(2) for group 1 and 582.39 +/- 327.13 mum/mm(2) for group 2. The mean fibre dia-meter was measured at 0.52 +/- 0.23 mum for group 1 and at 0.56 +/- 0.27 mum for group 2. Beadings of the nerve fibres were recorded at a density of 213 +/- 123/mm for group 1 and 201 +/- 192/mm for group 2. Establishing standards for normal nerve density and morphology of the living human cornea at different ages may be beneficial, both in early detection and follow up of various corneal diseases and in post-surgical management following corneal surgery.