[Laser surgery].

Three kinds of apparatus of CO2 laser, that is, Medilaser S, NIIC Lasery 60 and NIIC Lasery Model 60Z, are used in our institute. Two kinds of apparatus of Nd-YAG laser, that is, Molectron Model 8000 and Medilas are utilized also. We have used CO2 lasers for removal of tumors in 75 brain tumor cases and 9 spinal cord tumor cases. CO2 lasers were also used for hemostasis in the muscle layer and subcutaneous tissue in 31 neurosurgical cases. YAG lasers were utilized for removal of brain tumors in 20 cases and also hemostasis in the muscle and subcutaneous layers in various neurosurgical procedures in 24 cases. CO2 lasers and Nd-YAG lasers have their respective characteristics. We believe the neurosurgical procedures will be performed more safely and quickly, should these equipments be used properly. Clinical Materials: We have used CO2 lasers for removal of brain tumors in 75 cases including 40 cases of meningiomas. Out of the 40 cases 19 were basal meningiomas and the remaining 21 were either convexity meningiomas or falx and parasagittal meningiomas. Out of 75 cases of the brain tumors 21 were gliomas and the remaining 14 cases were micellaneous intracranial lesions consisting of 4 chordomas, 3 chemodectomas, 2 orbital tumors, 2 cholesteatomas, 1 pituitary adenoma, 1 dural AVM and 1 brain abscess. YAG lasers were used for removal of brain tumors in 20 cases. They were 7 basal meningiomas, 2 convexity meningiomas, 2 cerebellar hemangioblastomas, 2 orbital tumors, 2 pineal tumors, 1 chordoma, 1 facial neurinoma, 1 CP angle glioma, 1 intraventricular glioma and 1 temporal osteosarcoma. Results: For amputation of the tumors or vaporization of the tumor tissues, focused beams of CO2 laser 60W in output power were very effectively used in 15 cases including chemodectomas, pineal tumors and gliomas. YAG laser beams 100W, 0.5 sec. at 0.5 cm distance were used for making small holes in tough cyst walls of the teratomas in the pineal region for draining of soft contents and internal decompression of the tumors. Thereafter these deeply seated tumors were able to be removed totally without causing any damage to the surrounding neural structures. Separation of the cyst walls of gliomas from the adjacent normal brain tissue1)was performed easily in 3 cases using CO2 laser with near-focused beams of 30W in output