METHOD FOR PERFORMING RADIONUCLIDE OSTEOSCINTIGRAPHIC EXAMINATION OF MINERAL METABOLISM IN BONE TISSUE Russian patent published in 2019 - IPC A61B6/03 A61K51/00 A61P43/00 

FIELD: medicine.

SUBSTANCE: invention relates to medicine, specifically to radionuclide radionuclide diagnostics, and can be used for performing radionuclide osteoscintigraphic examination of mineral metabolism in bone tissue. Two-phase radionuclide osteoscintigraphic examination is performed: 5 minutes after the introduction of the radionuclide pharmaceutical preparation (RPP) in the phase of extravasal metabolism - the first phase and 120–180 minutes in the phase of incorporated activity - the second phase. Patient's body is scanned in the anterior and posterior projections at each phase of the examination. On the front projection image obtained at the first phase of the study, a zone of interest is constructed, which includes the entire human body, constructing a rectangular zone embracing the image of the human body. Then it is copied into other images. Constructing selected zone of interest at second phase of investigation: visually by comparing images of selected area of interest on all images detecting image containing zone of interest with most informative distribution of RPP. Zone of interest is confined therein, and the obtained boundaries of the zone of interest are copied into the homonymous image of the first phase of investigation. Level of RPP accumulation in the zone of interest at the first phase of the study is determined quantitatively by formula where K₁ Is the formalized coefficient of relative accumulation of the RPP in the selected zone of interest at the first phase of the study, in percents. OH₁ Is the radioactivity value measured in the selected zone of interest in pulses. D₁ - total activity recorded in the anterior and posterior projections when scanning the area of interest, including the whole human body, which is taken as the administered dose of RPP, in pulses. D₁=A_P1+A_Z1, where A_P1 - radioactivity measured at the first phase of the study when scanning the area of interest, including the whole human body, in a front projection, in pulses; A_Z1 - radioactivity measured at the first phase of the study when scanning the area of interest, including the whole human body, in the posterior projection, in pulses. Q is patient's body surface area, m². Q = M^0.425⋅D^0.725⋅0.007184, where M is patient's body weight, kg; D is the patient's height, cm. Then the RPP accumulation level in the zone of interest is determined in the second phase of the study quantitatively by the formula where K_K - formalized coefficient of RPP accumulation in the selected zone of interest at the second phase of the study, in percentage. OI_K Is the radioactivity value taking into account radioactive decay of the isotope measured in the selected zone of interest at the second phase of the study. D_K - incorporated dose of RPP taking into account radioactive decay of isotope, in pulses, measured during scanning of zone of interest, including whole body, at second phase of investigation. Q is patient's body surface area, m². where OI₂ Is radioactivity value without taking into account radioactive decay of isotope in pulses, measured in selected zone of interest at second phase of investigation. t is time interval between studies, in minutes. T_1/2 is isotope half-life, in minutes. where D₂ Is an incorporated RPP dose without taking into account radioactive decay of the isotope, measured when scanning the area of interest, which includes the whole human body, in the second phase of the study, in pulses. D₂= A_P2+ A_Z2-A_MP, where A_P2 - radioactivity measured at the second phase of the study when scanning the area of interest, including the whole human body, in the front projection, in pulses; A_Z2 - radioactivity measured at the second phase of the study when scanning the area of interest, including the whole human body, in the posterior projection, in pulses; A_MP - radioactivity measured in the second phase of the study in the bladder zone of interest in the anterior projection, in pulses.

EFFECT: method provides higher reliability of results of osteoscintigraphy studies, reliability of results of dynamic observations, simplified implementation, expanded field of use due to the possibility of quantitative evaluation of accumulation of osteotropic RPP in bone tissues in the selected area of interest both in localized and systemic skeletons.

1 cl, 12 dwg, 7 tbl, 2 ex

К₁ - K₁

ОИ₁ - OI₁

Д₁ - D₁

К_К - K_K

Д_К - D_K

ОИ_К - OI_K

Д₂ - D₂