PT  - JOURNAL ARTICLE
AU  - Thorsten Derlin
AU  - Benjamin A. Spencer
AU  - Martin Mamach
AU  - Yasser Abdelhafez
AU  - Lorenzo Nardo
AU  - Ramsey D. Badawi
AU  - Simon R. Cherry
AU  - Frank M. Bengel
TI  - Exploring Vessel Wall Biology In Vivo by Ultrasensitive Total-Body PET
AID  - 10.2967/jnumed.122.264550
DP  - 2023 Mar 01
TA  - Journal of Nuclear Medicine
PG  - 416--422
VI  - 64
IP  - 3
4099  - http://jnm.snmjournals.org/content/64/3/416.short
4100  - http://jnm.snmjournals.org/content/64/3/416.full
SO  - J Nucl Med2023 Mar 01; 64
AB  - Ultrasensitive, high-resolution, extended-field-of-view total-body (TB) PET using the first-of-its-kind 194-cm axial-field-of-view uEXPLORER may facilitate the interrogation of biologic hallmarks of hitherto difficult-to-evaluate low-signal vessel wall pathology in cardiovascular disease. Methods: Healthy volunteers were imaged serially for up to 12 h after a standard dose of 18F-FDG (n = 15) or for up to 3 h after injection of a very low dose (about 5% of a standard dose; n = 15). A cohort undergoing standard 18F-FDG PET (n = 15) on a conventional scanner with a 22-cm axial field of view served as a comparison group. Arterial wall signal, crosstalk with hematopoietic and lymphoid organs, and image quality were analyzed using standardized techniques. Results: TB PET depicted the large vessel walls with excellent quality. The arterial wall could be imaged with high contrast up to 12 h after tracer injection. Ultralow-dose TB 18F-FDG images yielded a vessel wall signal and target-to-background ratio comparable to those of conventional-dose, short-axial-field-of-view PET. Crosstalk between vessel wall and lymphoid organs was identified with better accuracy in both TB PET cohorts than in conventional PET. Conclusion: TB PET enables detailed assessment of in vivo vessel wall biology and its crosstalk with other organs over an extended time window after tracer injection or at an ultralow tracer dose. These initial observations support the feasibility of serial imaging in low-risk populations and will stimulate future mechanistic studies or therapy monitoring in atherosclerosis and other vessel wall pathologies.