The Application of a Contact Ncl-YAG Laser Scalpel to Head and Neck Surgery -A Fundament al and Clinical Study-

Abstract

We have developed a contact Nd-YAG laser technique with excellent incisional capabilities. The effects of the contact Nd-YAG laser irradiation on the wound healing in the rabbit skin and tongue was evaluated with respect to, (1) histological and immunohistochemical findings, (2) hydroxyproline levels in the wound and (3) reduction in the initial wound area. The histology and immunohistochemistry of the specimens treated by a contact Nd-YAG laser irradiation at 14 watts revealed numerous neutrophils and histiocytes with strong inflammatory reaction in the region adjacent to the incised areas 3 and 7 days after operation. Fibronectin could be seen around the incised areas. On the 12th day, inflammatory cells could still be seen, although the wound healing characterized by fibrosis and regeneration of the epithe lium was in advanced stages. The hydroxyproline levels in the wounds were signifi-- cantly lower in the laser groups 3 and 7 days after operation than in the surgical scalpel group (control group). On the 14th day, the level was slightly lower in the laser groups than in the control group. The reduction in the initial wound area in the laser groups, especially in the group irradiated at 14 watts, was slightly delayed compared to that in the control group. These findings suggested that the cure of wound, especially within 7 days after operation was slightly delayed following contact Nd-YAG laser irradiation at 14 watts compared to that by using the usual surgical scalpel. The contact Nd-YAG laser technique was clinically applied to the surgical operation of head and neck diseases in 238 patients: 105 malignant head and neck tumors,32 with benign tumors,96 with inflammatory diseases and 5 with other diseases. Satisfactory results were obtained. It was suggested that under appropriate irradiation conditions, the contact Nd-YAG laser technique was useful for operation of head and neck diseases.