CORNEAL REINNERVATION FOLLOWING PENETRATING KERATOPLASTY - CORRELATION OF ESTHESIOMETRY AND CONFOCAL MICROSCOPY

Thus far assessment of corneal reinnervation after penetrating keratop lasty has been possible only by esthesiometry techniques. Since the in troduction of confocal microscopy, we have been capable of performing structural corneal in vivo examinations. The purpose of our study was to correlate esthesiometry results with confocal microscopy findings. We used a Cochet-Bonnet esthesiometer and a Microphthal confocal micro scope to investigate corneal grafts in vivo. A total of 46 eyes were e xamined preoperatively and for up to 3 years after penetrating keratop lasty. At 8 weeks after keratoplasty the first stromal nerves were det ected in the periphery of the graft. The first nerves in the middle an d superficial stroma of the graft center were observed at 7 months aft er surgery. Reinnervation of the central basal epithelium was found at 2 years after keratoplasty. The highest level of sensitivity was dete cted in young patients with reinnervation of the basal epithelium. Con focal microscopy enables us to correlate morphologically and functiona lly corneal rf innervation after surgery. The present study shows that corneal reinnervation is influenced by the amount of time elapsing af ter surgery, the patient's age, and the preoperative diagnosis. In non e of our patients was normal nerve morphology or sensitivity observed during the follow-up period. Comparison of the morphology of nerves se en in eyes after nonsurgical trauma with that observed in corneal graf ts indicates that surgically induced scar formation may limit nerve re generation in grafts.