[Noninvasive imaging of vulnerable plaques and thromboses with PET/CT complex imaging technique]

To investigate the feasibility of identifying the vulnerable plaque and predicting plague rupture and thrombus using by positron emission tomography/computed tomography angiography (PET/CTA).

Twenty-eight male New Zealand white rabbits were fed with hyper-lipid diet for 2 weeks before the balloon injury of the abdominal aorta.Then these rabbit were intermittently fed with hyper-lipid diet for 14 weeks, in order to trigger pharmaceutic the plague rupture and thrombus. PET/CTA scans of abdominal aorta were performed before and after the drug triggering, FDG uptake (standardized uptake value, SUV) was measured. Rabbits were euthanized to obtain data of pathology and histology. The parameters obtained by PET/CTA, pathology and histology were compared and the correlations were performed.

The thrombosis was identified in 13 of 20 rabbits.Before the drug triggering, (18)F-FDG mean standardized uptake value (SUVmean) was higher in thrombotic arterial segments (defined as vulnerable plaque) (1.10 ± 0.19 vs 0.77 ± 0.11,P = 0.000); after the drug triggering, SUVmean was higher in thrombotic arterial segments, too (1.15 ± 0.26 vs 0.85 ± 0.17, P = 0.000). We use the ROC curve for SUVmean to predict plaque rupture and thrombosis. The area under the curve (AUC) was 0.898 (P = 0.000). The cutoff value was 0.882.

Our findings indicated that (18)F-FDG PET/CTA, as a noninvasive imaging method, could be used to identify vulnerable plaques and predict thrombosis events.