Laser coagulation in the upper GI tract: a preliminary light and scanning electron microscopic study.
Experimentally intact as well as artificially damaged mucosa of porcine stomach was endoscopically coagulated with Nd:YAG laser beams. Energy, intensity pattern, and time of application of the irradiation was varied and supracellular changes of the coagulated mucosa were subsequently investigated with the scanning electron microscope. The mucosa, damaged by laser beams, showed three typical zones: 1. a superficial, central carbonisation zone protected with a thin layer of coagulated mucus; 2. an elevated hyperemic ring with complete loss of superficial epithelium, but intact basement membrane and a blood clotting of the mucosal capillaries; 3. normal mucosa. After coagulating artificially induced bleeding of the mucosa the irradiated centre showed a deep depression with a carbonized surface. Two weeks later regeneration had occurred and there was complete reepithelialisation of the mucosa to about two-thirds of normal thickness.
D000818:Animals; D005753:Gastric Mucosa / Q000601:surgery* / Q000648:ultrastructure; D006471:Gastrointestinal Hemorrhage / Q000473:pathology / Q000601:surgery*; D006801:Humans; D053685:Laser Therapy; D007834:Lasers; D008855:Microscopy, Electron, Scanning; D013552:Swine