PennPET Explorer: Human Imaging on a Whole-body Imager

Abstract

The PennPET Explorer, a prototype whole-body imager currently operating with a 64-cm axial field-of-view (FOV), can image the major body organs simultaneously with higher sensitivity than that of commercial devices. We report here the initial human imaging studies on the PennPET Explorer with each study designed to test specific capabilities of the device. We demonstrate the ability to scan for shorter duration, or, alternatively with less activity, without a compromise in image quality. Delayed images, up to 10 half-lives with FDG, reveal biological insight and support the ability to track biologic processes over time. In one clinical patient, the PennPET Explorer better delineates extent of ¹⁸F-fluorodeoxyglucose (FDG)-avid disease. In a second clinical study with ⁶⁸Ga-DOTATATE we demonstrate comparable diagnostic image quality on the PennPET compared to the clinical scan, but with one-fifth the activity. Dynamic imaging studies capture relatively noise-free input functions for kinetic modeling approaches. Additional studies with experimental research radiotracers illustrate the benefits from the combination of large axial coverage and high sensitivity. These studies provide proof-of-concept for many proposed applications for a long axial FOV PET scanner.