Accurate total‐body <i>K<sub>i</sub></i> parametric imaging with shortened dynamic <sup>18</sup>F‐FDG PET scan durations via effective data processing
Zixiang Chen, Zhaoping Cheng, Yanhua Duan, Qiyang Zhang, Na Zhang, Fengyun Gu, Ying Wang, Yun Zhou, Haining Wang, Dong Liang, Hairong Zheng, Zhanli Hu
Abstract
Abstract Background Total‐body dynamic positron emission tomography (dPET) imaging using 18 F‐fluorodeoxyglucose ( 18 F‐FDG) has received widespread attention in clinical oncology. However, the conventionally required scan duration of approximately 1 h seriously limits the application and promotion of this imaging technique. In this study, we investigated the possibility and feasibility of shortening the total‐body dynamic scan duration to 30 min post‐injection (PI) with the help of a novel Patlak data processing algorithm for accurate K i estimations of tumor lesions. Methods Total‐body dPET images acquired by uEXPLORER (United Imaging Healthcare Inc.) using 18 F‐FDG of 15 patients with different tumor types were analyzed in this study. Dynamic images were reconstructed into 25 frames with a specific temporal dividing protocol for the scan data acquired 1 h PI. Patlak analysis‐based K i parametric imaging was conducted based on the imaging data corresponding to the first 30 min PI, during which a Patlak data processing method based on cubic Hermite interpolation was applied. The resultant K i images acquired by 30 min dynamic PET data and the standard 1 h K i images were compared in terms of visual imaging effect, region signal‐to‐noise ratio, and K i estimation accuracy to evaluate the performance of the proposed K i imaging method with a shortened scan duration. Results With the help of Patlak data processing, acceptable K i parametric images were obtained from dynamic PET data acquired with a scan duration of 30 min PI. Compared with K i images obtained from unprocessed Patlak data, the resulting images from the proposed method performed better in terms of noise reduction. Moreover, Bland–Altman plot and Pearson correlation coefficient analysis showed that that 30 min K i images obtained from the processed Patlak data had higher accuracy for tumor lesions. Conclusion Satisfactory K i parametric images with high tumor accuracy can be acquired from dynamic imaging data corresponding to the first 30 min PI. Patlak data processing can help achieve higher K i imaging quality and higher accuracy regarding tumor lesion K i values. Clinically, it is possible to shorten the dynamic scan duration of 18 F‐FDG PET to 30 min to acquire an accurate tumor K i and further effective tumor detection with uEXPLORER scanners.