Clinical Application of Low-Dose Total-Body PET/CT Scan

Conventional positron emission tomography–computed tomography (PET/CT) has a 15–30 cm axial field of view and often recommends a minimum image acquisition of 7 MBq/kg/min/bed [1, 2]. This translates to 2 min/bed for image acquisition and a standard dose of approximately 3.7 MBq/kg for 18F-fluorodeoxyglucose (FDG). With a 194-cm extra-long axial field of view, total-body (TB) PET/CT offers significantly increased system sensitivity, allowing for low-dose PET imaging. Half-dose PET imaging involves injecting only 1.85 MBq/kg instead of the recommended dose of 3.7 MBq/kg 18F-FDG, thereby reducing radiopharmaceutical costs, and enabling more patients to undergo imaging with limited 18F-FDG supply. Additionally, administering lower doses of imaging agents can lessen the radiation exposure risks for medical personnel during the procedures and has fewer irradiation effects on patients.