Improvement of Cold Artifacts in Body Trunk ¹⁸F-FDG PET/CT by Absolute-single scatter simulation: Validation in an Out-of-body High-accumulation Phantom

Purpose This study aimed to verify whether cold artifacts caused by the gap state between attenuation correction computed tomography (ACCT) and positron emission (PET) data (so-called hot-in-air (HIA) state) in body trunk PET/computer (CT) examinations can be improved Absolute-single scatter simulation (SSS), which is a method phantom experiment using high-accumulation syringe of out-of-body phantom. Method PET imaging profile curves HIA were evaluated that simulated urinary tract pouch encapsulated with 18F-FDG solution. The hot syringe-to-background ratio (HBR) was changed 5, 7, 10. Moreover, image quality evaluation performed placed on top NEMA IEC Six spheres (10-37 mm diameter) inside filled solution sphere-to-background 4. items N10 mm, QH, 10 / recovery coefficient (RC). Result tended deteriorate as HBR increased relative-SSS, while effect small Absolute-SSS lowest at RC10 5 0.33 for Relative-SSS, below criterion but 0.5 Absolute-SSS, met criterion. Conclusion significantly states PET/CT examinations, suggesting it highly useful both visually quantitatively.