Intra corneal ring segment implantation with lenticule assisted stromal augmentation for crosslinking in thin corneas

PURPOSE: To evaluate the safety and efficacy of intra corneal ring segment (ICRS) implantation combined with crosslinking (CXL) using a Small Incision Lenticule Extraction (SMILE) lenticule for intraoperative stromal augmentation in thin corneas. OBSERVATIONS: The procedure was performed in three eyes of progressive keratoconus or post refractive surgery corneal ectasia, with a preoperative mean thinnest pachymetry of 389.34 ± 5.5 μm. Keratometry flattening (preoperative mean maximum keratometry of 63.17 ± 9.31D to postoperative mean maximum keratometry of 54.77 ± 9.47D) and improvement in spectacle corrected distance visual acuity (mean preoperative LogMAR 0.43 ± 0.19 to mean postoperative LogMAR 0.71 ± 0.26) was noted at three months, with stability at one-year postoperative visit. Demarcation line was demonstrated at a depth of 220.67 ± 8.32 μm. No significant endothelial cell loss was noted. CONCLUSIONS AND IMPORTANCE: Intraoperative stromal thickness augmentation using a lenticule obtained from SMILE allows safe and effective CXL in combination with ICRS in ultrathin corneas. This allows an alternative to lamellar keratoplasty for visual rehabilitation in such eyes.