Development of modern approach to absorbed dose assessment in radionuclide therapy, based on Monte Carlo method simulation of patient scintigraphy

1st International Symposium 'Physics, Engineering and Technologies for Bio-Medicine'

医药卫生;物理学;工业技术

Lysak, Y.V.^1 ; Klimanov, V.A.^1 ; Narkevich, B.Ya.^2

National Research Nuclear University, MEPhI, 31 Kashirskoe highway, Moscow

115409, Russia^1

N. N. Blokhin Russian Oncological Research Center, 23 Kashirskoe highway, Moscow

115478, Russia^2

关键词: Absorption and scatterings;    Accumulated activities;    Calculation results;    Radiation transport;    Radionuclide therapy;    Regions of interest;    Scintigraphic images;    Therapeutic radionuclides;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/784/1/012035/pdf
DOI  :  10.1088/1742-6596/784/1/012035

来源: IOP

【 摘 要 】

One of the most difficult problems of modern radionuclide therapy (RNT) is control of the absorbed dose in pathological volume. This research presents new approach based on estimation of radiopharmaceutical (RP) accumulated activity value in tumor volume, based on planar scintigraphic images of the patient and calculated radiation transport using Monte Carlo method, including absorption and scattering in biological tissues of the patient, and elements of gamma camera itself. In our research, to obtain the data, we performed modeling scintigraphy of the vial with administered to the patient activity of RP in gamma camera, the vial was placed at the certain distance from the collimator, and the similar study was performed in identical geometry, with the same values of activity of radiopharmaceuticals in the pathological target in the body of the patient. For correct calculation results, adapted Fisher-Snyder human phantom was simulated in MCNP program. In the context of our technique, calculations were performed for different sizes of pathological targets and various tumors deeps inside patient's body, using radiopharmaceuticals based on a mixed β-γ-radiating (131I,177Lu), and clear β- emitting (89Sr,90Y) therapeutic radionuclides. Presented method can be used for adequate implementing in clinical practice estimation of absorbed doses in the regions of interest on the basis of planar scintigraphy of the patient with sufficient accuracy.