[Morphological findings of the mucosa after irradiation with an argon-laser an animal experiment (author's transl)].

The macroscopical and lightmicroscopical findings at the mucosa of the hamster cheek pouch after irradiation with an Argon-Ionlaser (wave-length 0.488 mum, power 200 mW, beam diameter 0.5 mm, power density 100 W/cm2) are described immediately, 1; 2,5; 5 and 10 days after irradiation. The mucosa was exposed 10 sec, 30 sec, 1, 2, 5 and 10 min to the radiation. With growing laser dosis the lesions of the mucosa and the postoperative healing time increases.A clinically useful optimal mucosa lesion with a short healing duration (within 5-10 days) is obtained only by application of a low and a middle laser dosis. There are two kinds of mucosa destruction by laser: 1. The destruction can be producing a coagulation necrosis with subsequent unbloody sloughing, resulting in an ulcus with rapid healing by complete reepithelisation and a small amount of connective tissue. 2. An immediate destruction is obtained by carbonisation of tissue after application of a middle to high laser dosis resulting in an ulcus with slow healing and also complete reepithelisation and small connective tissue. The typical laser lesion consists of 3 zones: The carbonisation zone is surrounded by a small coagulation zone followed by a zone of granulation tissue including thrombs and necrosis of the vessel walls. The unbloody procedure is based on an occlusion of the vessels immediately during laser radiation and later on by thrombosis in the periphery of the lesions. The possible clinical applications are discussed.