2020/10/01 by Michel Hesse, Hesse, Michel, Philipe d Abadie +7
Medicine · Physics and Astronomy · #Advanced Radiotherapy Techniques #FOS: Physical sciences #Instrumentation and Detectors (physics.ins-det) #Medical Imaging Techniques and Applications #Medical Physics (physics.med-ph) #Radiopharmaceutical Chemistry and Applications
paper · pdf · doi:10.48550/arxiv.2010.00303
openalex publication_date 2020/10/01 · openalex created_date 2022/07/25 · openalex updated_date 2026/07/28
Purpose: Explaining why 90Y TOF-PET based equivalent uniform dose (EUD) using\nstandard FDG reconstruction parameters has been shown to predict response.\n Methods: The hot rods insert of a Jaszczak deluxe phantom was partially\nfilled with a 2.65 GBq 90Y - 300ml DTPA water solution resulting in a 100 Gy\nmean absorbed dose in the 6 sectors. A two bed 20min/position acquisition was\nperformed on a 550ps- and on a 320ps- TOF-PET/CT and reconstructed with\nstandard FDG reconstruction parameters, without and with additional filtering.\nThe whole procedure was repeated on both PET after adding a 300ml of water\n(50Gy setup). The phantom was acquired again after decay by a factor 10 (5Gy\nsetup), but with 200min per bed position. For comparison the phantom was also\nacquired with 18F activity corresponding to a clinical FDG whole body\nacquisition.\n Results: The 100Gy-setup provided hot rod sectors image almost as good as in\n18F phantom. However, despite acquisition time compensation the 5Gy-setup\nprovides much lower quality imaging. TOF-PET based sectors EUDs for the three\nlarge rod sectors were in agreement with the actual EUDs computed with a\nradiosensitivity 0.021Gy-1 well in the range observed in external beam\nradiotherapy (EBRT), i.e. 0.01-0.04Gy-1. This agreement explains the\nreunification of the dose-response relationships of the glass and resin spheres\nin HCC using the TOF-PET based EUD. Additional filtering reduced the EUDs\nagreement quality.\n Conclusions: Standard FDG reconstruction parameters are suitable in TOF-PET\npost 90Y liver radioembolization for accurate tumor EUD computation. The\npresent results clearly rules out the use of low specific activity phantom\nstudies to optimize reconstruction parameters.\n