In 2012, Italian ophthalmologist Massimo Busin introduced a lamellar keratoplasty (LK) technique for keratoconus using a microkeratome that involves the exchange of a 9mm anterior recipient lamella with donor tissue. His technique adds a 6.5mm incomplete full-thickness trephination of the recipient bed before suturing the donor graft in place.1 Dr. Busin and his team recently presented the 10-year results of their modified procedure in the British Journal of Ophthalmology.2
The single-center, interventional case series included 151 eyes with keratoconus that underwent the modified LK procedure. At baseline, best spectacle-corrected visual acuity was 0.89 logMAR. This improved significantly to 0.1 logMAR at three years and remained stable at 10 years. At the 10-year mark, 94% of eyes saw 20/40 or better, 61% saw 20/25 or better and 24% saw 20/20 or better.2
At one year, endothelial cell loss was 25%, and the researchers noted that this declined 2% over 10 years. Immunological rejection risk and graft failure over 10 years were 8.5% and 2.4%, respectively. At the final follow-up exam, only 4% of cases had refractive astigmatism greater than 4.5D. No eyes developed recurrent ectasia during the 10-year follow-up period.2
The researchers concluded that modified microkeratome-assisted LK results in stable outcomes with low rates of rejection in the long-term.2 While nonbaring LK—dissection of the deep stroma without exposing Descemet’s layer—may result in a “keratoconus memory” preserved in the residual recipient stroma, which may cause recurring ectasia, the modified LK procedure’s additional incision in the recipient bed cancels out this “memory.”1
“The effect of this modification was such that average postoperative simulated keratometric readings were similar to those found after penetrating keratoplasty and less myopic than those observed after deep anterior LK of other types,” the researchers explained in their paper.1
1. Busin M, Scorcia V, Zambianchi L, et al. Outcomes from a modified microkeratome-assisted lamellar keratoplasty for keratoconus. Arch Ophthalmol. 2012;130(6):776-82.
2. Yu AC, Franco E, Caruso E, et al. Ten-year outcomes of microkeratome-assisted lamellar keratoplasty for keratoconus. Br J Ophthalmol. October 3, 2020. [Epub ahead of print].