[Keratoplasty: laminate or penetrate? Part 2: lamellar keratoplasty]

A number of corneal disorders sooner or later call for a decision as to whether corneal grafting is necessary. In contrast to the current gold standard, penetrating keratoplasty (PKP), former lamellar techniques had the disadvantage of worse visual outcomes due to interface problems. A number of recent new technical developments have led to a 'renaissance' of various lamellar keratoplasty methods. Deep anterior lamellar keratoplasty (DALK) avoids the risk of endothelial immune reactions. However, visual outcomes are comparable to PKP only is complete baring of Descemet's membrane is achieved. In Descemet stripping (automated) endothelial keratoplasty [DS(A)EK], a variation of posterior lamellar keratoplasty, only the diseased endothelium is removed with the Descetmet membrane (descemetorhexis). The lamellar, endothelium-bearing graft can subsequently be implanted via a corneoscleral/corneal tunnel, whereby little astigmatism is induced. The main advantage of DS(A)EK compared to PKP is faster visual recovery with almost unaltered refraction, although visual acuity is often slightly lower. However, valid study results are still lacking for this new surgical technique to allow a long-term comparison of the new techniques with conventional penetrating keratoplasty.