Corneal sub-basal nerve changes in patients with herpetic keratitis

Abstract

Aim To describe corneal sensitivity and morphological changes of sub-basal corneal nerves using in vivo laser scanning confocal microscopy (LSCM) in HSV keratitis affected eyes during acute phase of the disease and after 6 months. Methods A prospective clinical study included 269 patients divided into 3 groups: 79 - with active unilateral HSV keratitis, 101 healthy patients with previous history of herpes labialis and 89 patients with no history of HSV diseases. All of the patients underwent a complete ophthalmological examination, Cochet-Bonnet aesthesiometry and LSCM of the central cornea. After 6 months the patients with herpetic eye disease underwent the same examination. Serology tests of the serum to detect HSV 1/2 IgG, IgM were performed. Results HSV affected eyes compared with contralateral eyes, herpes labialis and healthy control group eyes demonstrated a significant decrease in corneal sensitivity, corneal nerve fibre density, corneal nerve branch density, corneal nerve fibre length and corneal nerve total branch density (p < 0.05). The parameters of contralateral eyes were also decreased comparing with healthy controls (p<0.05). During follow up after 6 months, corneal sensitivity and sub-basal nerve parameters had increased but did not reach the parameters of contralateral eyes (p<0.05). The best recovery of corneal sensitivity was seen in patients with epithelial keratitis. Previous herpes labialis did not influence corneal sensitivity and was not a risk factor for herpetic eye disease. Conclusions Corneal sensitivity and sub-basal nerve changes in HSV affected eyes revealed a significant decrease. Following 6 months, corneal sensitivity and sub-basal nerve parameters increased; however, they did not reach the parameters of contralateral eyes and the eyes of healthy controls.