Advances in corneal transplantation.

For many corneal diseases, transplantation is the gold standard for curative treatment and restoration of vision. Penetrating keratoplasty (PKP), performed by Zirm in 1905, was the first successful corneal transplantation procedure. Since then, relentless advancement in the field has occurred, most importantly with the development of deep anterior lamellar keratoplasty (DALK), Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK), which have been rapidly increasing in usage and are poised to take over PKP in prevalence and effectiveness in treating specific stromal and endothelial pathologies. The biggest issues currently facing this field are the lack of availability of donor corneas and lack of accessibility of the procedure to many areas of the world. Recent and future advancements are focused on substitutes to increase the amount of graft material for use and technological developments to streamline keratoplasty techniques, making them more effective, easier to perform and associated with less complications. Bio-engineered corneas, cell-based therapies and regenerative medicine can create grafts through various mechanisms: acellular, synthetic scaffolds and medical therapies to promote endogenous cell regeneration or exogenous cultivation of corneal tissues from stem-cells. Keratoplasty has also been refined by the introduction of femtosecond laser (FSL), which when combined with intra-operative optical coherence tomography (iOCT) allows for finer cuts and novel techniques which can improve the outcomes from PKP, DALK and DMEK.