Normal values for 18F-FDG uptake in organs and tissues measured by dynamic whole body multiparametric FDG PET in 126 patients

Abstract

Background Dynamic whole-body (D-WB) FDG PET/CT is a recently developed technique that allows direct reconstruction of multiparametric images of metabolic rate of FDG uptake (MRFDG) and “free” FDG (DVFDG). Multiparametric images have a markedly different appearance than the conventional SUV images obtained by static PET imaging, and normal values of MRFDG and DVFDG in frequently used reference tissues and organs are lacking. The aim of this study was therefore to: (1) provide an overview of normal MRFDG and DVFDG values and range of variation in organs and tissues; (2) analyse organ time-activity curves (TACs); (3) validate the accuracy of directly reconstructed MRFDG tissue values versus manually calculated Ki (and MRFDG) values; and (4) explore correlations between demographics, blood glucose levels and MRFDG values. D-WB data from 126 prospectively recruited patients (100 without diabetes and 26 with diabetes) were retrospectively analysed. Participants were scanned using a 70-min multiparametric PET acquisition protocol on a Siemens Biograph Vision 600 PET/CT scanner. 13 regions (bone, brain grey and white matter, colon, heart, kidney, liver, lung, skeletal muscle of the back and thigh, pancreas, spleen, and stomach) as well as representative pathological findings were manually delineated, and values of static PET (SUV), D-WB PET (Ki, MRFDG and DVFDG) and individual TACs were extracted. Multiparametric values were compared with manual TAC-based calculations of Ki and MRFDG, and correlations with blood glucose, age, weight, BMI, and injected tracer dose were explored. Results Tissue and organ MRFDG values showed little variation, comparable to corresponding SUV variation. All regional TACs were in line with previously published FDG kinetics, and the multiparametric metrics correlated well with manual TAC-based calculations (r2 = 0.97, p < 0.0001). No correlations were observed between glucose levels and MRFDG in tissues known not to be substrate driven, while tissues with substrate driven glucose uptake had significantly correlated glucose levels and MRFDG values. Conclusion The multiparametric D-WB PET scan protocol provides normal MRFDG values with little inter-subject variation and in agreement with manual TAC-based calculations and literature values. The technique therefore facilitates both accurate clinical reports and simpler acquisition of quantitative estimates of whole-body tissue glucose metabolism.

Multiparametric dynamic whole-body PSMA PET/CT using [68Ga]Ga-PSMA-11 and [18F]PSMA-1007

“…These advances have prompted renewed interest and research in the use of dynamic PET for oncological imaging as reviewed elsewhere [23,24]. While the multiparametric D-WB protocol has been successfully applied for 2-[ 18 F]fluoro-2-deoxy-D-glucose ([ 18 F]FDG) [25][26][27], it has until now only to a lesser degree been explored for other tracers.…”

Synthesis of Prospective Multiple Time Points F-18 FDG PET Images from a Single Scan Using a Supervised Generative Adversarial Network

“…In this modality, internal dosimetry has emerged as the most crucial issue, and numerous studies have emphasized its significant role in radiation protection, optimization of the injection dose, and improvement of image quality [1]. Absorbed dose calculation after intravenous administration of F-18 FDG is highly dependent on the organ time-activity-curve (TAC) [2], the area under the curve (AUC), and cumulative activity map estimation, which are the cornerstones of quantitative imaging evaluation [3].…”

Small nuclei identification with a hemispherical brain PET

“…Therefore, whole-body PET and Vrain were initiated 30 min and 45 min after injection, respectively. The time difference is one limitation of this study because during this time, the accumulation of FDG slightly increases in the brain grey matter as it approaches the plateau and almost reaches a plateau in the white matter [ 25 ]. The clearer visualization of the brain images with Vrain might be partially attributed to this time difference.…”