Johan Wassélius

It has been shown that [¹⁸F]-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) can identify macrophage-rich high-risk atherosclerotic plaques in animal models as well as in patients with atherosclerotic plaques in the carotid arteries. The development of inflamed macrophage-rich plaques over time is not well known. This study was performed to determine the variability of such FDG-accumulating plaques between consecutive PET/CT examinations. Twenty-eight patients who underwent two whole-body FDG-PET/CT examinations within 7 months for malignant diseases were re-evaluated for atherosclerotic lesions in major arterial segments. The plaques were identified as active, inactive, or mixed depending on their appearance on PET and CT. Every identified plaque was compared with that of the other examination to evaluate the time-to-time correlation. The time-to-time correlation was close to 100% for calcified inactive plaques and about 50% for FDG-accumulating active plaques, with a high consistency between all examined arterial segments in this material. A large proportion of FDG-accumulating plaques can be identified on consecutive FDG-PET/CT examinations within 7 months.

Graft infection is a serious complication to vascular surgery. The aim of this study was to assess ¹⁸F-FDG uptake in vascular grafts in patients with or without symptoms of graft infection. Methods: In all 2,045 patients examined by PET/CT at our clinic, 16 patients with synthetic aortic grafts were identified and reevaluated for ¹⁸F-FDG accumulation. Clinical and biochemical data were obtained from patient records. Results: High ¹⁸F-FDG uptake was found in 10 of 12 grafts in the patients who underwent open surgery and in 1 of 4 grafts in patients who underwent endovascular aneurysm repair. On the basis of biochemical and clinical data, it was concluded that 1 of the 16 patients had a graft infection at the time of investigation. Conclusion: ¹⁸F-FDG uptake in vascular grafts was found in the vast majority of patients without graft infection. The risk of a false-positive diagnosis of graft infection by ¹⁸F-FDG PET/CT is evident.

Purpose The aim of this study was to assess the atherosclerotic plaques in a large asymptomatic population stratified based on age and sex. Methods [18F]-2-fluoro-2-deoxy-d-glucose (FDG)-PET/CT of 100 men and 100 women, divided in four age groups were examined to assess FDG-accumulating active, calcified inactive and mixed atherosclerotic plaques in eight defined vessel segments. Results There was a high correlation between the total number of cardiovascular risk factors and the number of FDG-accumulating active plaques as well as the number of calcified inactive plaques. There was a significant difference in the number of plaques between all age-groups except for active plaques in age groups 60–70 and 80–90 years. Conclusions There is a correlation between the number of cardiovascular risk factors and the number of FDG-accumulating atherosclerotic lesions in this patient material. Statin-treatment was associated with significantly lower numbers of active plaques.