Comparison of SUV A /V and SUV A -V for Evaluating Atherosclerotic Inflammation in 18 F-FDG PET/CT

Purpose This study aimed to compare the clinical significance of two parameters, division of standardized uptake value (SUV) of target arterial activity by background venous blood pool activity (SUV A/V ) and subtraction of background venous blood pool activity from SUV of target arterial activity (SUV A-V ) of carotid arteries with atherosclerotic plaques using 18 F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT). Methods Patients aged 50 years or more who were diagnosed with carotid artery stenosis of 50% or more with carotid Doppler ultrasonography and had torso 18 F-FDG PET/CT were enrolled retrospectively and classified patients who developed cerebrovascular events (CVEs) within 5 years after 18 F-FDG PET/CT scan as the active group and patients who did not experience the CVE within 5 years as an inactive group. We calculated SUV A/V and SUV A-V using measurements of SUV max of carotid arteries and mean SUV of superior vena cava (SVC). Results SUV A-V , SUV A-V_high , and SUV A-V_low were significantly higher in the active group than in the inactive group, but neither SUV A/V , SUV A/V_high , nor SUV A/V_low showed significant differences between the active and inactive groups. The difference in rank between groups of SUV A/V_high and SUV A/V_low was greater than the difference in rank between groups of SUV A-V_high and SUV A-V_low . The CVE incidence differed between SUV A/V_high and SUV A/V_low of high carotid FDG uptake, but the CVE incidence did not differ between SUV A-V_high and SUV A-V_low of high carotid FDG uptake. Conclusion SUV A-V may be a more rational solution than SUV A/V for evaluating atherosclerotic plaque inflammation on 18 F-FDG PET/CT.