The epithelial barrier function in clear corneal grafts

We conducted a corneal epithelial permeability study using a fluorophotometer on 93 eyes of 79 patients with clear corneal grafts. There were 45 males and 34 females, aged 61.6 +/- 10.2 years. All eyes received penetrating keratoplasty at least 1 year (mean 40.4 +/- 31.3 months) before examination. The normal fellow eyes of 65 subjects were examined as controls. The averaged corneal epithelial permeability of grafted corneas was significantly higher than that of controls (p < 0.001). In the 65 individuals having an otherwise healthy fellow eye, the grafted corneas were significantly more permeable than their control fellow eyes verified by paired t test (n = 65, p = 0.006). Concomitant corneal sensitivity test revealed a significantly hypesthetic cornea. These results show that in spite of a clinically normal clear graft, there is usually a subnormal epithelial barrier function and reinnervation, even years after corneal transplantation.