The Femtosecond Laser – A Promising Tool for Keratoplasty

Abstract

Abstract: : Purpose: We focus on developing a safer, more precise and reliable method for both lamellar and penetrating keratoplasty compared to common procedures. Using near–infrared femtosecond laser pulses enables us to perform computer controlled three–dimensional cuts in the corneal tissue of both donor and recipient. Methods: Laser pulses of 150 fs duration and a repetition rate of 5 kHz are focused inside corneal tissue of porcine cadaver eyes. Within the focal plane each laser pulse causes a point–shaped micro cavity by photodisruption of the tissue. A multitude of micro cavities placed close to each other forms continuous macroscopic cuts. A galvanometer scanner is used for precise three–dimensional positioning of fs–pulses inside the cornea. Results: Three–dimensional cuts can be performed inside the corneal tissue. Thus the size and the shape of the corneal transplant can be adjusted to individual needs. Different three–dimensional shapes which allow for simplified positioning and adapting the donor’s transplant to the recipient eye are demonstrated. The transfer of corneal tissue cut by fs–laser from one porcine cadaver eye to another has been successfully shown. Conclusions: Cutting corneal tissue with fs–lasers will potentially simplify the procedure of keratoplasty. The fs–laser enables the surgeon to create transplants of whatever shape is needed. Thus the transplant can be matched more accurately with the recipient’s eye. The use of trephines may become redundant.

Keywords: cornea: clinical science • transplantation