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

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 SUVmean 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.

Input function and modeling for determining bone metabolic flux using [18F] sodium fluoride PET imaging: A step‐by‐step guide

“…It should be noted that additional doses may be delivered to the patient from other procedures, for example, the computed tomography (CT) part of the PET‐CT scan, which will vary depending on the tube current and CT scan time. Studies have shown that it is possible to obtain a successful quantitative [ 18 F]NaF PET scan at the lumbar spine using an injected activity as low as 90 MBq, 13,14 and some researchers have proposed further dose reduction strategies in preclinical settings 41 . However, radiation dosimetry is a field in itself, and this topic will not be discussed here any further.…”

“…Studies have shown that it is possible to obtain a successful quantitative [ 18 F]NaF PET scan at the lumbar spine using an injected activity as low as 90 MBq, 13,14 and some researchers have proposed further dose reduction strategies in preclinical settings. 41 However, radiation dosimetry is a field in itself, and this topic will not be discussed here any further.…”