Donor Tissue Preparation for Bowman Layer Transplantation

Purpose: To describe and compare 2 preparation techniques for Bowman layer (BL) grafts for use in BL transplantation. Methods: A retrospective evaluation of the 2 methods for preparing BL grafts was performed, that is, BL graft preparation from donor globes not eligible for penetrating keratoplasty or endothelial keratoplasty (technique I, n = 36) and BL graft preparation from previously excised corneoscleral buttons (technique II, n = 36) that could not be used for PK or had been denuded of Descemet membrane and endothelium for Descemet membrane endothelial keratoplasty graft preparation. BL graft preparation difficulties were recorded, and the preparation failure rate was examined and compared between the techniques. Results: Overall, BL graft preparation was successful in 51 cases (51/72; 70.8%), of which 25 preparations were successful using technique I, and 26 using technique II, representing a success rate of 69.4% (25/36) and 72.2% (26/36) for techniques I and II, respectively. Reasons for discarding a BL graft were tearing of the BL tissue during the preparation (n = 19) and stroma attached to the graft (n = 2). Conclusions: Isolated BL grafts can be prepared from both whole donor globes and corneoscleral rims with equivalent success. Preparation from corneoscleral rims may offer the advantage that, from one donor cornea, the posterior layers can be used for Descemet membrane endothelial keratoplasty graft preparation and the anterior part for BL graft preparation.