Accuracy of FDG-PET–CT in the Diagnostic Work-up of Vascular Prosthetic Graft Infection

Abstract

Objectives To investigate the diagnostic accuracy of fluoro-2-deoxy- d-glucose positron emission tomography (FDG-PET) compared with computed tomography (CT) scanning and added value of fused FDG-PET–CT in diagnosing vascular prosthetic graft infection. Design Prospective cohort study with retrospective analysis. Materials Twenty five patients with clinically suspected vascular prosthetic infection underwent CT and FDG-PET scanning. Methods Two nuclear medicine physicians assessed the FDG-PET scans; all CT scans were assessed by two radiologists. Fused FDG-PET/CT were judged by the radiologist and the nuclear medicine physician. The concordance between CT and FDG-PET and the inter-observer agreement between the different readers were investigated. Results Fifteen patients had a proven infection by culture. Single FDG-PET had the best results (sensitivity 93%, specificity 70%, positive predictive value 82% and negative predictive value 88%). For CT, these values were 56%, 57%, 60% and 58%, respectively. Fused CT and FDG-PET imaging also showed high sensitivity and specificity rates and high positive and negative values. Inter-observer agreement for FDG-PET analysis was excellent (kappa = 1.00) and moderate for CT and fused FDG-PET–CT analysis (0.63 and 0.66, respectively). Conclusion FDG-PET scanning showed a better diagnostic accuracy than CT for the detection of vascular prosthetic infection. This study suggests that FDG-PET provides a useful tool in the work-up for diagnosis of vascular prosthetic graft infection.