Wound Repair By Laser Welding

In this study, we have developed a concept of wound closure by laser welding and studied the wound healing process. In the first set of experiments, six-millimeter long, full-thickness incisions were made in the skin on the back of hairless mice. Control wounds were closed with interrupted 5-0 prolene suture. The experimental wounds were approximated and closed by laser welding using a Nd:YAG (1.06 μm) laser. Selected wounds were excised for histopathology, transmission electron microscopy, tensile strength determination and assay of type I collagen specific messenger-RNA. The laser welded wounds demonstrated rapid healing with good cosmetic results. The tensile strength was identical both for laser welded and sutured wounds at 7, 16, and 21 days. A significant increase of type I collagen specific mRNA was noted in both specimens at 4, 10 and 16 days, but a higher level was recorded in the sutured specimens at day 16 (2652 vs. 911 U/pg total RNA). We further initiated a comparative study to identify the laser which would be most suitable for skin welding. For this purpose argon, Nd:YAG (1.06 μm and 1.32 μm) and CO 2 lasers were used to weld skin. Wound healing, tensile strength and collagen analyses were performed. The results indicated that both argon and Nd:YAG (1.32 μm) lasers achieved the most effective closure. These results suggest that laser welding provides an efficient method for closing skin wounds. The laser welding has clear advantages over conventional suturing techniques, being sterile, non-tactile, not requiring introduction of foreign materials into the wound, and providing improved cosmetic results.