Standardized ‘no‐touch’ donor tissue preparation for DALK and DMEK: harvesting undamaged anterior and posterior transplants from the same donor cornea

Abstract

To describe a standardized 'no-touch' harvesting technique of anterior and Descemet membrane (DM) grafts for use in deep anterior lamellar keratoplasty (DALK) and Descemet membrane endothelial keratoplasty (DMEK), which provides undamaged anterior and posterior corneal grafts. A retrospective evaluation was performed of our standard method for harvesting DM grafts and DALK grafts (Technique I; n = 31) versus a newly designed 'no-touch' technique (Technique II; n = 31), in which a peripheral ring of trabecular meshwork tissue is left in-situ, and the DM graft is trephined on an underlying soft contact lens. Endothelial cell density (ECD) before and immediately after DM stripping was used as the main outcome parameter. Endothelial cell density did not differ within Techniques I and II (before versus after DM stripping) (p = 0.75 and p = 0.54, respectively) or among Techniques I and II (p = 0.61). With the latter technique, anterior corneal grafts and posterior DM grafts could be harvested with negligible damage to the endothelial cell layer or the posterior stromal bed. All 93 grafts (62 DM grafts) were eligible for transplantation, and six months post-operatively all transplants used were functional. The new technique offers the following advantages: (i) production of 'undamaged' grafts for DALK and DMEK, (ii) better controlled tissue handling of the thin DM graft during DM stripping and (iii) an increase in availability of corneal grafts obtained from the same donor tissue pool.