[18F] Sodium Fluoride Dose Reduction Enabled by Digital Photon Counting PET/CT for Evaluation of Osteoblastic Activity

Maria I Menendez; Richard R Moore; Mahmoud Abdel-Rasoul; Chadwick L Wright; Soledad Fernandez; Rebecca D Jackson; Michael V Knopp

doi:10.3389/fmed.2021.725118

[¹⁸F] Sodium Fluoride Dose Reduction Enabled by Digital Photon Counting PET/CT for Evaluation of Osteoblastic Activity

Front Med (Lausanne). 2022 Jan 12:8:725118. doi: 10.3389/fmed.2021.725118. eCollection 2021.

Authors

Maria I Menendez¹, Richard R Moore¹, Mahmoud Abdel-Rasoul², Chadwick L Wright¹, Soledad Fernandez², Rebecca D Jackson³, Michael V Knopp¹

Affiliations

¹ Department of Radiology, The Wright Center of Innovation in Biomedical Imaging, The Ohio State University Wexner Medical Center, Columbus, OH, United States.
² Center for Biostatistics, College of Medicine, The Ohio State University, Columbus, OH, United States.
³ Department of Internal Medicine, Endocrinology, Diabetes and Metabolism, The Ohio State University Wexner Medical Center, Columbus, OH, United States.

Abstract

The aim of the study was to assess the quality and reproducibility of reducing the injected [¹⁸F] sodium fluoride ([¹⁸F]NaF) dose while maintaining diagnostic imaging quality in bone imaging in a preclinical skeletal model using digital photon counting PET (dPET) detector technology. Beagles (n = 9) were administered three different [¹⁸F]NaF doses: 111 MBq (n = 5), 20 MBq (n = 5), and 1.9 MBq (n = 9). Imaging started ≃45 min post-injection for ≃30 min total acquisition time. Images were reconstructed using Time-of-Flight, ultra-high definition (voxel size of 1 × 1 × 1 mm³), with 3 iterations and 3 subsets. Point spread function was modeled and Gaussian filtering was applied. Skeleton qualitative and quantitative molecular image assessment was performed. The overall diagnostic quality of all images scored excellent (61%) and acceptable (39%) by all the reviewers. [¹⁸F]NaF SUV_mean showed no statistically significant differences among the three doses in any of the region of interest assessed. This study demonstrated that a 60-fold [¹⁸F]NaF dose reduction was not significantly different from the highest dose, and it had not significant effect on overall image quality and quantitative accuracy. In the future, ultra-low dose [¹⁸F]NaF dPET/CT imaging may significantly decrease PET radiation exposure to preclinical subjects and personnel.

Keywords: PET/CT; [18F] sodium fluoride; bone imaging; bone metabolism; canine PET; digital photon counting; preclinical molecular imaging; sodium fluoride dose reduction.