Femtosecond DALK not a substitute for manual techniques

ROME — Femtosecond laser-assisted deep anterior lamellar keratoplasty is not, at this time, a valid alternative to the manual technique, according to several surgeons at the winter meeting of the European Society of Cataract and Refractive Surgeons.

Deep stromal dissection with a regular, smooth interface can be easily obtained with a femtosecond laser. However, in advanced keratoconus, the geometry of the residual bed appears to be non-homogeneous. It is thinner at the apex of the conus and thicker in the periphery.

Both Vincenzo Sarnicola, MD, and Leonardo Mastropasqua, MD, explained that an automated procedure that uses a reference profile for dissection depth of the anterior surface of the cornea will consequently match the different thicknesses centrally and peripherally and cut a lamella with an irregular profile.

There are also concerns about the regularity and quality of the graft interface.

"The tissue bridges that are a limitation in the horizontal cuts produced by the current femtosecond technology inevitably cause difficulties in detaching the lamella, resulting in irregularities and poor interface quality," Massimo Busin, MD, said.

Manual techniques will remain the standard procedure until further advances in the femtosecond technology overcome these problems.