The fundamenal and clinical studies on the endoscopic laser therapy of the protruding lesions

Laser has been utilized for endoscopic therapy of the protruding lesions. Animal experiments were performed before applying it to clinical trials. The results obtained from animal experiments and the findings by clinical trials were reported. 1. The beam of YAG laser is able to enter a microscope lens system and be focused on the proximal end of a 80μ diameter quartz fiber with the aid of a micropositioner. 2. The transmittance of this optical fiber is about 50% for YAG laser. 3. This waveguide protected by a thin flexible teflon tube can be passed down the biopsy channel of any standard fiberoptic endoscopy. (GIF-P2, GIF-D3, GTF-B2, GF-B2) 4. The distance from the tip of the waveguide to the lesion can be varied without moving the endoscope because the waveguide can be inserted and withdrawn in the same way as a biopsy forceps during diagnostic endoscopy. 5. Directions for use of laser are the radiation method and the contact method. The depth of injury in the tissues induced by the contact methods is deeper than by the radiation mothods. 6. Endoscopic laser treatment was performed in 36 lesions without accidental complications. 7. While performing polypectomy the contact methods are utilized for coagulation of center of polyp and polyp root. 8. The postoperative ulceration has healed within three weeks. 9. The specimens removed by endoscopic laser photocoagulation cannot be withdrawn except for the pedunclated polyp. Therefore, while performing endoscopic laser polypectomy it is desirable to try to remove the polyp of Yamada and Fukutomi type I, II and IV.