E.E. Anokina1, A.V. Likhacheva2, L.A. Chipiga3

1 National Medical Research Center of Oncology n.a. N.N. Petrov (St. Petersburg, Russia)
2,3 Saint-Petersburg Research Institute of Radiation Hygiene n.a. Professor P.V. Ramzaev (Saint-Petersburg, Russia)
3 The City Hospital No 40 of the Kurortny District (Saint-Petersburg, Russia)
3 A. Granov Russian Scientific Center of Radiology and Surgical Technologies (Saint-Petersburg, Russia)
3 Almazov National Medical Research Centre (Saint-Petersburg, Russia)
1 ekaterinaanokina@yandex.ru, 2 nastya.petryakova@gmail.com, 3 larisa.chipiga@gmail.com

Radionuclide therapy requires high accuracy in the quantitative assessment of radionuclide activity for effective planning and monitoring of cancer treatment. One of the key evaluation methods is single-photon emission computed tomography (SPECT), which makes it possible to visualize the distribution of radiopharmaceuticals in the body. Accurate determination of activity allows for better prediction of absorbed doses, leading to safer and more effective treatment protocols. However, the accuracy of quantitative activity assessment in SPECT studies is limited by the effects of gamma-ray scattering, radiation attenuation, the partial volume effect, and collimator imperfections.

The aim of this study was to summarize the literature data on factors influencing the accuracy of quantitative assessment in SPECT in order to identify optimal settings of SPECT scanners, scanning protocols, and image reconstruction techniques for imaging during radionuclide therapy with different radionuclides. Particular attention was paid to the use of volume-dependent calibration factors and phantom measurements to improve reliability under clinical conditions.

As a result of the study, it was demonstrated that accuracy of quantitative analysis can be significantly improved by applying iterative reconstruction methods with collimator response compensation and multi-window scatter correction. The use of phantom models and calibrations with calibration factors reduces errors in the assessment of radionuclide activity. The practical significance of the results lies in improving the reliability of dosimetry calculations in radionuclide therapy, which contributes to greater treatment effectiveness and reduces the risk of complications associated with patient over- or underexposure.

Anokina E.E., Likhacheva A.V., Chipiga L.A. Current Approaches to Quantitative Assessment of SPECT for Therapeutic Radionuclides. Biomedicine Radioengineering. 2025. V. 28. № 7. P. 64–75. DOI: https:// doi.org/10.18127/ j15604136-202507-07 (In Russian)

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