18 F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Enables the Detection of Recurrent Same-Site Deep Vein Thrombosis by Illuminating Recently Formed, Neutrophil-Rich Thrombus

Abstract

Background— Accurate detection of recurrent same-site deep vein thrombosis (DVT) is a challenging clinical problem. Because DVT formation and resolution are associated with a preponderance of inflammatory cells, we investigated whether noninvasive 18 F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) imaging could identify inflamed, recently formed thrombi and thereby improve the diagnosis of recurrent DVT. Methods and Results— We established a stasis-induced DVT model in murine jugular veins and also a novel model of recurrent stasis DVT in mice. C57BL/6 mice (n=35) underwent ligation of the jugular vein to induce stasis DVT. FDG-PET/computed tomography (CT) was performed at DVT time points of day 2, 4, 7, 14, or 2+16 (same-site recurrent DVT at day 2 overlying a primary DVT at day 16). Antibody-based neutrophil depletion was performed in a subset of mice before DVT formation and FDG-PET/CT. In a clinical study, 38 patients with lower extremity DVT or controls undergoing FDG-PET were analyzed. Stasis DVT demonstrated that the highest FDG signal occurred at day 2, followed by a time-dependent decrease ( P <0.05). Histological analyses demonstrated that thrombus neutrophils ( P <0.01), but not macrophages, correlated with thrombus PET signal intensity. Neutrophil depletion decreased FDG signals in day 2 DVT in comparison with controls ( P =0.03). Recurrent DVT demonstrated significantly higher FDG uptake than organized day 14 DVT ( P =0.03). The FDG DVT signal in patients also exhibited a time-dependent decrease ( P <0.01). Conclusions— Noninvasive FDG-PET/CT identifies neutrophil-dependent thrombus inflammation in murine DVT, and demonstrates a time-dependent signal decrease in both murine and clinical DVT. FDG-PET/CT may offer a molecular imaging strategy to accurately diagnose recurrent DVT.