An interventional study to evaluate surgical outcomes after descemets membrane endothelial keratoplasty(DMEK) and pre-descemets endothelial keratoplasty(PDEK) for corneal endotheliopathies

Until the last years of last century, Penetrating Keratoplasty (PK) was theonly way to surgically treat endothelial dysfunction. . Since then there has been a major change in medical management of thesepathologies.

A technique of EK is  Descemet Membrane Endothelial Keratoplasty (DMEK). It involves removal of Descemet’s membrane andendothelium,but with replacement of only these two layers without posteriorstroma. It claims an even faster visual recovery and better visual outcome thanwith DSAEK(Also a technique of EK)       Pre‑Descemet’s EK (PDEK) is a newer variant in the arena of EK , is a novel procedure and itinvolves the separation of PDL along with DM‑endothelium asa donor lenticule after performing descemetorrhexis. Accordingto proponents of the technique PDEK offers the ability to use corneal tissuefrom younger donars.

The most significant advantage of PDEK is that it is notdependent on the corneal donor age, whereas DMEK cannot be done unless thedonor is above 40 years of age, given the increased tendency for graftscrolling. Additionally, a PDEK graft is advantageous in that it is only 25 µmto 30 µm thick, minimizing graft-host interface postoperative haze. Notably,even though the PDEK graft is thin, the pre-Descemet’s layer preservationwithin the graft is the critical component that allows for ease of graftmovement within the eye, minimizing the risk of graft tearing.