For penetrating keratoplasty (PKP), the zig-zag profile with angled edges inspired by self-sealing cataract incisions provides more surface area for wound healing, greater mechanical stability of wound incisions and better incision alignment, according to Dr Farid,

  who recommended a posterior bridge of uncut tissue of 70 μm. This dissection pattern for PKP using the femtosecond laser technology has been shown to be clearly superior to conventional trephination in terms of visual acuity and astigmatism control, always using the same size and profile for host and donor.

  One additional advantage of the zig-zag profile, as pointed out by Prof. Alió, is that coaptation of the donor-host interface in PKP is better compared to top-hat or mushroom patterns. This was confirmed in a study evaluating donor-host interface elevation using optical coherence tomography (OCT) conducted by his team.

  In contrast, the mushroom pattern does not automatically align the anterior surface, but preserves more host endothelium.

Articles

The authors present highlights of the fourth FemtoKeratoplasty meeting held earlier this year.