18F] FDG PET/CT can improve the diagnostic accuracy for aortic endograft infection

Abstract

Purpose Aortic endograft infection (EI) can result in potentially life-threatening vascular complications. Unfortunately, it is difficult to obtain a correct diagnosis at an early stage in many patients. This report aims at validating the use of [18F] FDG PET/CT imaging for suspected endograft infections in a prospectively collected cohort of patients treated with EVAR and TEVAR. Materials and methods During a 14-year period, 366 patients required aortic stent graft. All procedures were performed electively, except for one patient. Among these 366 patients, eleven patients (3%) were suspected to have aortic EI. Contrast-enhanced CT and FDG PET/CT were performed in all 11 patients. Medical charts and imaging were analysed for these 11 cases, with initial positive CT. Results The final diagnosis of EI was established in seven (1,9%) based on clinical features, laboratory investigations and a significant [18F] FDG uptake in the aortic graft as well as the aortic wall. The median time from the initial EVAR/TEVAR to diagnosed infection was 180 days. During follow-up, the seven patients had a second PET/CT that was compared with the initial evaluation, decreased uptake was correlated with clinical improvement. Conclusions Contemporary diagnostic imaging for a potentially lethal endograft infection lacks precision, this observational study illustrates the potential clinical value of [18F] FDG PET/CT in the management of aortic EI. [18F] FDG PET/CT constitutes an imaging modality able to confirm the diagnosis, monitor disease progression as well as the effect of pharmaceutical treatment and detect relapse.