FDG-PET/CT as a diagnostic tool in vascular graft infection: a systematic review and meta-analysis

Abstract

Vascular graft infection (VGI) in central grafts is a rare but dreaded complication with a high mortality. Several imaging modalities are employed, all with pros and cons. Computed tomography is the standard, but lacks sensitivity for low-grade infections. There is still no consensus regarding the diagnostic modality of choice. The study objective was to assess the role of combined positron emission tomography and computed tomography with fluorodeoxyglucose (FDG-PET/CT) in the diagnostic workup of VGI in central grafts. A systematic review was conducted according to the PRISMA guidelines through a search in Embase, PubMed, and Cochrane databases. Meta-analysis on accuracy measures was carried out with random effects models for three parameters: focal uptake, visual grading scale (VGS), and maximum standardized uptake value (SUVmax). Heterogeneity among studies was assessed with the I-squared test. A total of 307 studies were identified and 9 were eligible for inclusion. The pooled estimates for sensitivity and specificity for focal uptake were 90.6% (95% CI 81.7–99.4%) and 82.8% (95% CI 71.3–94.3%), respectively, for VGS 86.8% (95% CI 59.3–100%) and 69.4% (95% CI 39.9–98.9%), respectively, for SUVmax 92.8% (95% CI 83.2–100%) and 69.7% (95% CI 52.4–86.9%), respectively. A single study employed tissue-to-background ratio (TBR) and found sensitivity and specificity of 71.8% (95% CI 54.6–84.4%) and 70.4% (95% CI 51.5–84.2%), respectively. According to this systematic review and meta-analysis, FDG-PET/CT performs well especially when using focal versus diffuse FDG uptake to diagnose VGI.