Modern keratoplasty techniques have evolved, becoming targeted procedures to remove and replace only the diseased and affected layers of the cornea. Modern keratoplasty procedures include penetrating keratoplasty (PK), a full-thickness procedure removing and replacing all layers of the cornea; deep anterior lamellar keratoplasty (DALK), removing and replacing corneal tissue while preserving the hosts’ Descemet’s membrane and endothelium; and endothelial procedures such as Descemet stripping endothelial keratoplasty (DSEK) and Descemet membrane endothelial keratoplasty (DMEK), in which Descemet’s membrane and endothelial layers are removed from the host and replaced with donor tissue, the former having a layer of posterior stroma attached to Descemet’s membrane and the endothelial layer while the latter is just Descemet’s membrane and endothelium. Various techniques can be utilized to dissect the cornea during PK; the primary two techniques are manual dissection using a trephine punch, yielding a perpendicular cut through the cornea, and femtosecond laser-assisted dissection, allowing for more precision, customized size, and incision shapes such as zig zag, mushroom, and top hat configurations (Figure 1).Figure 1. One-month post-op femtosecond laser-assisted penetrating keratoplasty (PK) utilizing a mushroom incision with a 9.0mm anterior diameter and 7.5mm posterior diameter. Note overlap of tissue at the graft-host junction.The reasons for keratoplasty are vast. A review of the Eye Bank Association of America’s annual report for the past three years determined that keratoconus is the number one reported indication for PK and anterior lamellar keratoplasty.1-3 The second most common reported indication for PK is a repeat corneal transplant.1-3 For the purposes of this article, we will be discussing contact lens management post-PK.It has been suggested in the literature that the number of keratoplasties performed for keratoconus is decreasing as a result of corneal cross-linking, which can stop the progression of the disease and effectively prevent advanced levels of keratoconus from occurring,4,5 and the utilization of scleral contact lenses, which allows individuals who have severe keratoconus and individuals who have been deemed contact lens intolerant another option to achieve stable, comfortable visual correction, thus avoiding keratoplasty.6 However, until the day when corneal disease is eliminated, practitioners will need to find options for correcting vision after keratoplasty.
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