Customized Stromal Lenticule Implantation for Keratoconus

PURPOSE: To investigate the potential benefit of keratoconus surgery using customized corneal stromal donor lenticules obtained from myopic small incision lenticule extraction (SMILE) surgery by femtosecond laser. METHODS: In this prospective, consecutive, non-comparative series of cases, 22 lenticules were obtained from 22 myopic patients who had SMILE with a lenticule central thickness of greater than 110 µm. The lenticules were implanted in 22 eyes with advanced keratoconus. The lenticules were customized for the purpose of the implantation with either a simple necklace or necklace-with-ring shape (compound form) depending on the corneal thickness and corneal topography configuration of the implanted keratoconic eyes. The lenticules were implanted into a 9.5-mm corneal lamellar pocket created by the femtosecond laser. Changes in densitometry, thickness, confocal microscopy, corrected distance visual acuity (CDVA), and endothelial cell density were investigated. RESULTS: Intrastromal lenticule implantation was successfully performed in all cases without any complication. Corneal thickness showed a mean enhancement of 100.4 µm at the thinnest point. On biomicroscopy, all corneas were clear at 1 year postoperatively and there was a significant improvement in corneal densitometry during the entire follow-up period. Confocal biomicroscopy showed collagen reactivation without any inflammatory features caused by the implanted fresh lenticules. CDVA improved from 0.70 to 0.49 logMAR ( P = .001) and keratometry decreased from 54.68 ± 2.77 to 51.95 ± 2.21 diopters ( P = .006). CONCLUSIONS: Customized SMILE lenticule implantation by femtosecond laser proved to be feasible, resulting in an improvement in vision, topography, and refraction in the implanted eyes. [ J Refract Surg . 2020;36(12):786–794.]