Abstract
Purpose:
The goal was to achieve a setup that allows precise docking of the laser as well as easy handling of the recipient and donor corneas for an ALK (anterior lamellar keratoplasty) using biosynthetic corneal collagen implants. Before starting in vivo trails in the rabbit eye, the trial setup was tested ex vivo on porcine and rabbit eyes. Furthermore the diameter, depth and surface of the recipient bed as well as the diameter and thickness of the biosynthetic cornea were examined.
Methods:
We used two different laser platforms on eyes of two different species (porcine eyes and rabbit eyes). One was the Victus Femto-laser-System (Technolas Perfect Vision, Germany) and a Prototype Excimer Laser (M-Lase, Germany). On both lasers the biosynthetic donor tissue was cut first (Diameter 600µm). The donor tissue (thickness 350µm) was placed on a porcine eye to facilitate placement under the laser aperture. The recipient porcine and rabbit eyes were treated with the same parameters (Diameter 600µm, depth 350µm). In case of the eximer laser two specially designed aluminum masks had to be used to achieve the desired diameter and shape of the cuts. The diameter, depth(stromal bed), thickness (donor tissue) and surface structure were evaluated histologically (paraffin embedded, HE staining) and by OCT Imaging as well as electronmikroskopy.
Results:
Both laser systems allowed precise cutting of the biosynthetic corneal implants as well as the donor tissue. The excimer laser treatment provided a smoother surface structure regarding the stromal bed, but the treatment duration was significantly longer than the treatment duration of the femto-second laser laser.
Conclusions:
Both laser platforms offer precise cutting options of the donor and recipient tissue. Although both treatment setups in the ex vivo animal trials showed promising results, the in vivo setup (presented separately) might be a greater challenge regarding positioning, docking and cutting parameters.
Keywords: 479 cornea: clinical science •
575 keratoprostheses