Photorefractive Keratectomy Eyes for Preparation of Pre-cut ‎Endothelial Keratoplasty Tissues

This study reported preparation and thickness profiles of pre-cut endothelial keratoplasty tissues in donated photorefractive keratectomy (PRK) eyes. Precut tissues for endothelial keratoplasty were dissected from PRK donor whole eyes by using Moria microkeratome at the Central Eye Bank of Iran. The tissues were then subjected to specular microscopy and Visante optical coherence tomography. Endothelial cell density (ECD) and thickness measurements of the precut tissues were evaluated. Additionally, eye bank post-operative reports of the transplanted corresponding endothelial tissues were reviewed. Between October 2015 and March 2016, 25 donor whole eyes from 14 sero-negative donors with the diagnosis of prior PRK were dissected to provide precut endothelial keratoplasty lenticules. The mean central thickness of the precut tissues was 128±34µm. A mean increase of 26.2 µm was observed from central to pericentral parts of the precut tissues. The mean increase of thickness from central to peripheral locations was 90.4 µm. There was a statistical difference in the mean increase of thickness between 2 peripheral locations (P = 0.047). All the precut tissues had a very good to excellent endothelial rating with the mean ECD of 3164.6±311.0 cell/mm2. On review of the postoperative reports, all the corresponding precut tissues were transplanted uneventfully and none of the reports indicated posterior flap detachment or loss of graft clarity. Thin precut tissues with high endothelial cell density can be successfully prepared from donated PRK whole eyes for endothelial keratoplasty. The increase of thickness towards peripheral locations of the precut tissues, despite being statistically asymmetric, was not clinically significant.