Total-Body PET Multiparametric Imaging of Cancer Using a Voxelwise Strategy of Compartmental Modeling

The Journal of Nuclear Medicine

article

Guobao Wang¹  Lorenzo Nardo¹  Mamta Parikh²  Yasser G. Abdelhafez¹  Elizabeth Li³  Benjamin A. Spencer¹  Jinyi Qi³  Terry Jones¹  Simon R. Cherry¹  Ramsey D. Badawi¹ 

[1] Department of Radiology, University of California Davis Medical Center;UC Davis Comprehensive Cancer Center;Department of Biomedical Engineering, University of California at Davis

关键词: image processing;    PET;    radiotracer tissue kinetics;    compartmental modeling;    parametric imaging;    total-body dynamic PET;   

DOI  :  10.2967/jnumed.121.262668

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

Quantitative dynamic PET with compartmental modeling has the potential to enable multiparametric imaging and more accurate quantification than static PET imaging. Conventional methods for parametric imaging commonly use a single kinetic model for all image voxels and neglect the heterogeneity of physiologic models, which can work well for single-organ parametric imaging but may significantly compromise total-body parametric imaging on a scanner with a long axial field of view. In this paper, we evaluate the necessity of voxelwise compartmental modeling strategies, including time delay correction (TDC) and model selection, for total-body multiparametric imaging. Methods: Ten subjects (5 patients with metastatic cancer and 5 healthy volunteers) were scanned on a total-body PET/CT system after injection of 370 MBq of 18F-FDG. Dynamic data were acquired for 60 min. Total-body parametric imaging was performed using 2 approaches. One was the conventional method that uses a single irreversible 2-tissue-compartment model with and without TDC. The second approach selects the best kinetic model from 3 candidate models for individual voxels. The differences between the 2 approaches were evaluated for parametric imaging of microkinetic parameters and the 18F-FDG net influx rate, Ki. Results: TDC had a nonnegligible effect on kinetic quantification of various organs and lesions. The effect was larger in lesions with a higher blood volume. Parametric imaging of Ki with the standard 2-tissue-compartment model introduced vascular-region artifacts, which were overcome by the voxelwise model selection strategy. Conclusion: The time delay and appropriate kinetic model vary in different organs and lesions. Modeling of the time delay of the blood input function and model selection improved total-body multiparametric imaging.

【 授权许可】

CC BY