Impact of time of flight and point spread function on quantitative parameters of lung lesions in 18F-FDG PET/CT

BMC Medical Imaging

Kemin Huang¹  Yanlin Feng¹  Lin Li¹  Weitang Liang¹ 

[1] Department of Nuclear Medicine, The First People’s Hospital of Foshan, 528000, Foshan, Guangdong, China;

关键词: Tomography;    Emission computer;    Time of flight;    Point spread function;    Quantitative parameters;    Standard uptake value;   

DOI  :  10.1186/s12880-021-00699-w

来源: Springer

【 摘 要 】

BackgroundImage reconstruction algorithm is one of the important factors affecting the quantitative parameters of PET/CT. The purpose of this study was to investigate the effects of time of flight (TOF) and point spread function (PSF) on quantitative parameters of lung lesions in 18F-FDG PET/CT.MethodsThis retrospective study evaluated 60 lung lesions in 39 patients who had undergone 18F-fluoro-deoxy-glucose (FDG) PET/CT. All lesions larger than 10 mm in diameter were included in the study. The PET data were reconstructed with a baseline ordered-subsets expectation–maximization (OSEM) algorithm, OSEM + PSF, OSEM + TOF and OSEM + TOF + PSF respectively. The differences of maximum standard uptake value (SUVmax), mean standard uptake value (SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG)and signal to noise ratio (SNR)were compared among different reconstruction algorithms.ResultsCompared with OSEM reconstruction, using OSEM + TOF + PSF increased SUVmean and SUVmax by 23.73% and 22.71% respectively, and SNR increased by 70.18%, MTV decreased by 23.84% (p < 0.01). The percentage difference was significantly higher in smaller lesions (diameter 10–22 mm) than in larger lesions (diameter 23–44 mm), and significantly higher in low contrast lesions (SNR ≤ 15.31) than in high contrast lesions (SNR > 15.31). The difference of TLG among various reconstruction algorithms is relatively small, the highest value is − 6.48% of OSEM + TOF + PSF, and the lowest value is 0.81% of OSEM + TOF.ConclusionTOF and PSF significantly affected the quantitative parameters of lung lesions in 18F-FDG PET/CT. OSEM + TOF + PSF can significantly increased SUVmax, SUVmean and SNR, and significantly reduce MTV, especially in small lesions and low contrast lesions. TLG can be relatively stable in different reconstruction algorithms.

【 授权许可】

CC BY