Processing of Donor Tissue for PDEK

In 2013, Harminder Dua MD (UK) was the first to describe a pre-Descemet’s layer (PDL) of collagen, present between the corneal stroma and DM [1], and Dr. Amar Agarwal MD (India) applied this knowledge to produce a new EK variant: pre-Descemet membrane endothelial keratoplasty (PDEK) [2]. PDEK has a number of advantages over previous EK methods. For one, PDEK donor graft is thicker (than DMEK) and is of about 25–30 microns. In addition, it permits the use of younger tissue (dramatically increasing the potential donor pool) and it also yields tissue that typically has a far greater endothelial cell density than typical DMEK grafts. The result should be a faster resolution of post-procedural corneal edema and improved graft longevity relative to DMEK-prepared grafts (Figs. 5.1 and 5.2).