PDEK in Complex Cases

Pre-Descemet’s Endothelial Keratoplasty or PDEK refers to transplantation of the Pre-Descemet’s layer or Dua’s layer, Descemet’s membrane and endothelium [1, 2]. This surgery has certain advantages as the PDEK graft is tougher, resilient as well more resistant to tearing than the DMEK graft. This allows the easier use of a technique that has been described by the author—“the air pump assisted PDEK/ DMEK technique” for surgery and therefore allows one to harness all the advantages of this technique [3–5]. This technique has many advantages and can be used for various purposes in PDEK surgery such as to make Descemetorhexis easier, to tamponade bleeding from the peripheral iridectomy or from synechiolysis, to allow edge unfolding, centration and uncreasing of the graft (Fig. 10.1), to maintain a formed AC and to act like a third hand supporting the graft from beneath. Though the technique can be harnessed in DMEK as well, for some of the steps, it cannot be used for edge unfolding or centration as the DMEK graft, unlike the PDEK graft is much more delicate and can tear with these maneuvers. PDEK can thus be performed more easily then DMEK in complex cases.