Prospective evaluation of PermaVision intracorneal implants using in vivo confocal microscopy

PURPOSE: To report effects of the PermaVision intracorneal lens at the cellular level using in vivo confocal microscopy. METHODS: Four eyes implanted with intracorneal lenses beneath an IntraLase flap for correction of hyperopia were evaluated preoperatively and 1 to 6 months postoperatively. RESULTS: Intracorneal lenses were tolerated in three eyes with little or no haze observed clinically and good visual results. Minimal keratocyte activation was detected by confocal microscopy, and cell density was decreased posterior to the implants. Epithelial thinning was observed 1 month after implantation. Thickness stabilized by 6 months but remained thinner than baseline (33±2 μm vs 48±8 μm, P<.01). The fourth eye had a complicated course with early flap displacement followed by diffuse lamellar keratitis. Confocal microscopy revealed activated keratocytes throughout the anterior stroma. The implant was removed, and recovery was promising. CONCLUSIONS: Implantation of intracorneal lenses can induce side effects of epithelial thinning, keratocyte loss, and keratocyte activation.