Precision Individual Dosimetry in Yttrium-90 Transarterial Radioembolization in the Presence of Au Nanoparticles Publisher



Talebi AS¹ ; Mehnati P¹ ; Rajabi H² ; Rezaei H^{3, 4} ; Geramifar P⁵ Show Affiliations
Source: Radiation Physics and Chemistry Published:2024

Abstract

Individual post-treatment dosimetry plays a crucial role in assessing the effectiveness of Y-90 transarterial radioembolization (TARE) treatment. Y-90 positron emission tomography (PET) imaging is widely regarded as the gold standard for post-TARE dosimetry. However, a major limitation of Y-90 PET imaging is the low positron yield of Y-90. This study aimed to address this limitation and improve individual dosimetry using Au nanoparticles (NPs)-induced pair production in Y-90 PET imaging. The GATE Monte Carlo platform was used to simulate post-TARE PET imaging. The study examined five levels of Au NP concentration in the liver tumor: 1%, 5%, 10%, 15%, and 20% by weight. The quality of the acquired PET images was evaluated by calculating the signal-to-background ratio (SBR) and contrast-to-noise ratio (CNR). The errors in PET-based dose volume histograms (DVHPET-based) and reference dose volume histograms (DVHrefrence) were evaluated through various metrics, including root-mean-square error (RMSE), mean absorbed dose (Dmean), and maximum absorbed dose (Dmax). The results showed that as the concentration of Au NPs increased in the tumor, the CNR and SBR values also increased. At concentrations 5 wt% and above, the difference in the values of Dmean and Dmax obtained from the reference dosimetry and PET-based dosimetry is less than 5%. The calculated RMSE values indicated that concentrations 5 wt% and above exhibited acceptable agreement between the DVHPET-based and DVHrefrence. When the concentration of Au NPs increases up to 5 wt%, the presence of Au NPs within the tumor does not significantly affect the Dmean. Conversely, with the presence of Au NPs, at concentrations of 10, 15, and 20 wt%, the Dmean within the tumor experiences reductions of approximately 6%, 10%, and 14%, respectively. The pair production was induced by simultaneously injecting Y-90 and Au NPs into the tumor. Our study demonstrated that dosimetry accuracy in TARE improved through induced positron PET imaging. As a consequence of the dose reduction phenomenon observed upon introducing Au NPs into the tumor, the optimal concentration of Au NPs for enhancing dosimetric precision was determined to be 5 wt%. © 2024 Elsevier Ltd