With the use of the developed opto-fiber spectroscope and
gastroscope, the intensity of fluorescence from the
ulcer surface into the gastrointestinal tract was measured in the range of 670-690 nm under the He-Ne
laser (= 632.8 nm) illumination. Surface fluorescence data were collected with the use of a special diagnostic fiber with a total diameter of about 2 mm, which combines some illuminating and receiving fibers. To do the measurements, the diagnostic fiber was brought into a slight contact with the mucosa surface. The quantitative results were calculated with the use of the special fluorescent contrast coefficient (Kf), which takes into account the backscattered light as well. After the fluorescent diagnostic procedure, the
low-level laser therapy was applied to all patients. It was found that: first of all, during the
laser medical cure the registered fluorescence for the patients with a good dynamics of treatment had an evident tendency to a decrease, and the coefficient Kf for observed
ulcers tended to approach the value obtained from normal mucosa (Kf), which indicates the normalization of the
porphyrin content in the tissue. Second, the retrospective analysis of the efficacy of
laser therapy versus initial values of Kf showed that, for the patients with the initial values Kf = 0.2, the efficiency of the
laser treatment was the highest: the relation between the patients with good treatment results and bad ones was 4:1 (more than 80%). For the initial Kf = 0.2-0.3, this relation was 3:1 but for Kf = 0.4-0.5 it was 2:3. The differences in the efficiency of the
low-level laser therapy, except the cases of the
cancer in the
ulcers, may be due to different content of
porphyrin in the tissue: at high concentrations of the
photosensitizer in the
ulcer, the effect of the overdosing could be realized. In this case, another technology of
laser illumination is needed. The results are discussed in terms of the
free-radical conception of the stimulating effect of
laser radiation.