In vivo imaging of abdominal aortic aneurysms: increased FDG uptake suggests inflammation in the aneurysm wall.

Truijers, Maarten; Kurvers, Harrie A J M; Bredie, Sebastian J H; Oyen, Wim J G; Blankensteijn, Jan D

PURPOSE To study the potential of integrated positron emission tomography and computed tomography (PET/CT) to identify aneurysm wall inflammation. METHODS The level of F18-fluorodeoxyglucose (FDG) uptake was studied in aneurysmal and normal-sized aortas of 34 male patients [17 with abdominal aortic aneurysm (AAA) and 17 age-matched controls] identified in a database of 278 consecutive patients evaluated for staging of primary lung cancer. The maximal standardized uptake value (SUV) was calculated to quantify FDG uptake in the AAA wall. RESULTS AAAs showed significantly higher FDG uptake than the normal-sized aorta in age-matched controls (SUV 2.52+/-0.52 versus 1.78+/-0.45, respectively; p<0.001). The level of FDG uptake did not correlate with maximal aneurysm diameter (r=0.09; 95% CI -0.42 to 0.56; p=0.7). CONCLUSION FDG-PET/CT is a promising technique to identify inflammation of the aneurysm wall. Irrespective of aneurysm diameter, asymptomatic AAAs show more FDG uptake and more inflammatory activity in the wall than the non-dilated abdominal aorta of sex/age-matched controls. Future studies will be directed at the predictive value of increased FDG uptake for aneurysm wall strength, rupture risk, and the utility of FDG-PET/CT in assessing the effect of medical interventions.