Abstract: | An argon ion laser beam was tested experimentally with regard to its histological effect on and penetration of the gastric mucosa of the rat and man and its ability to induce haemostasis in traumatically produced gastric lesions and transected small blood vessels. Localized laser photocoagulation for periods of up to 5 minutes at 1 watt produced a coagulative necrosis of the gastric mucosa and half of the muscularis propria, but transmural necrosis required prolonged exposure. Laser phototherapy markedly reduced the bleeding time in experimental ulcers and small blood vessels, provided the superficial blood could be adequately dispersed from the direct beam of the laser. |