29th Annual Meeting of the American Society of Photobiology

Downtown Marriot

Chicago, Il.

Controlled laser welding of tissue: experimental and clinical applications in Microsurgery and Ophthalmology

Abstract-
We present a review of our previous and current experimental researches on laser welding of tissue. In our approach, the welding process is based on controlled irradiation of tissue by diode laser radiation (805 nm) operating at very low power (30-60 mW) in association with a photoenhancing chromophore, applied locally. The induced welding effect is very effective and selective, without side effects to the adjacent tissue. In many surgical procedures, laser welding can provide simplification of the technique, reduction of suture material and of foreign body reaction. We started our studies in microsurgery performing laser-assisted end-to-end microvascular anastomosis on femoral arteries and veins of rats and rabbits without stitches. Moreover, significant results were obtained from follow up studies where histology examinations indicated a better and faster healing process in comparison with the one of traditional suturing procedures. Similar outcomes were obtained in laser welding of vas deferens and skin, both performed in animal models. More recently, after a 4-years-long pre-clinical experimentation, we clinically applied laser welding of the cornea on voluntary patients. This technique was firstly tested in corneal cuts of increasing lengths on 25 patients subjected to cataract surgery. Then we performed the first application of diode laser-assisted corneal welding to penetrating keratoplasty (transplantation of the cornea) to substitute the application of the continuous suture. Up to now, 4 patients have been treated. Objective examinations at the end of the interventions, as well as up to 90th post-op. day, confirmed the positive results of the previous experimental phases.

Keywords: laser welding, chromophore, cornea, diode laser