METHOD FOR PHOTODYNAMIC THERAPY OF ONCOLOGICAL DISEASES Russian patent published in 2015 - IPC A61N5/06 

FIELD: medicine.

SUBSTANCE: invention refers to medicine and can be used to select individual radiation-measuring parameters of a laser therapy of an individual's tissues. The tissue is exposed to a broad-band visible and near-IR radiation. The tissue diffuse reflection spectrum is measured. The tissue diffuse reflection spectrum shows its structural-morphological parameters, including the tissue concentration of blood vessels f_bl and photosensitiser C_ps, as well as the relative blood contents of oxyhaemoglobin S and methaemoglobin C_MetHb. The tissue spatial brightness spectrum F(z, λ) is stated with using a tissue optical radiation transfer model and the derived values of its structural-morphological parameters. Wave lengths and laser light powers, as well as the tissue exposure time providing the greatest light absorption by the photosensitiser and the best oxygen generation at a depth of a pathological segment of the tissue or throughout with the minimal exposure of the laser light on the healthy tissue are derived from distributed light absorption efficiency by the photosensitiser K_ps(z, λ) and photochemical dissociation efficiency of oxyhaemoglobin n(z, λ) by the light wave length λ and the tissue depth z calculated by expressions: K_ps(z, λ)=C_psε_ps(λ)F(z, λ), $$n(z,\lambda )=f_{bl}S(C_{tHb}/{\mu }_{tHb}){\epsilon }_{Hb{O}_2}(\lambda )Ф(z,\lambda )(q\lambda /hc),$$ wherein ε_ps and $${\epsilon }_{Hb{O}_2}$$ are molar absorption coefficients by the photosensitiser and oxyhaemoglobin, C_tHb=150 g/l is the average blood haemoglobin concentration, µ_tHb=64500 g/mole is the molar weight of haemoglobin, h is the Plank's constant; c is a light velocity in the medium; q is a quantum yield of photochemical dissociation of oxyhaemoglobin.

EFFECT: method enables determining the laser exposure parameters optimum for specific parameters, increasing the photodynamic therapeutic effectiveness and minimising the side effects of the treatment by monitoring the tissue concentration of the photosensitiser and oxyhaemoglobin, and the light absorption efficiency in the tissue layers with different depths, as well as by controlling the morphological changes of the exposed tissue.

15 dwg, 2 tbl