We have developed a new type of probe for endoscopic Nd: YAG laser treatment of digestive tract diseases. This probe is cylindrically shaped and is made from aluminium alloy. The transmittance for Nd:YAG laser beam was 83% when distilled water (2.0ml/min)flowed through the probe and it was 95% when CO₂ (400ml/min) flowed through the probe.Endoscopic Nd: YAG laser treatment for several clinical cases using the probe was effective at a power output of 20 to 30 watts. Adhesion of coagulated tissue does not occur because distilled water always flows out from the top of the probe. Breakdown of the probe does not occur because the Nd: YAG laser beam does not hit the inside of the probe. In other words the probe is durable and safe.
Endoscopic Nd: YAG laser treatment using the proe was efficacious and safe in 12 patients with 12 lesions of gastric cancer and 6 patients with 6 lesions of gastric flat adenoma.

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We investigated the distribution of pheophorbide a (Phd) and 10-hydroxypheophorbide a (OH-phd) in organs of sarcoma 180-bearing mice after intravenous (iv) administration at the dose of 10mg/kg.
The blood concentration of Phd and OH-phd (Phds) showed the high-level at lhr after iv administration, then rapidly decreased, and disappeared at 24hr.
Phds distributed mainly in the liver, spleeen, lung, kidney, gastrointestinal tract and tumor tissue, then decreased with the course of time.
OH-phd as compared with Phd, was excreted rapidly from all normal organs and not detected at 48hr after iv administration, but remained in the tumor tissue preferentially even at 96hr.

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The bursting and tensile strength of laser-assisted anastomosis (LA) was assessed and compared with conventional suture anastomosis (CA) using a standard rabbit carotid artery model.
LA arteries demonstrated lower bursting strengths than those of CA controls, with significant differences at 3 days (p<0.01). LA arteries anastomosed with 3 stay sutures demonstrated lower bursting strengths than 4 or 5 stay sutures at 1 hour (p<0.01). These results may explain the late aneurysm formation. Additional stay suture seemed to prevent such complication.
LA arteries consistently demonstrated lower tensile strengths than those of CA with significant differences at 1 hour, 3 days(p<0.01), and 7 days(p<0.05).

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