[Frontiers in Bioscience 14, 3352-3360, January 1, 2009]
Imaging of early inflammation in low-to-moderate carotid stenosis by 18-FDG-PET

M.Angels Font1, Alex Fernandez2, Ana Carvajal1, Cristina Gamez2, Lina Badimon3, Mark Slevin3,4 Jerzy Krupinski1,3,5

1Department of Neurology, University Hospital of Bellvitge (HUB), Fundacio Idibell, Barcelona, Spain, 2Institut de Diagnostic per la Imatge (IDI), University Hospital of Bellvitge (HUB), Fundacio Idibell , Barcelona, Spain, 3Centro de Investigacion Cardiovascular, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain, 4School of Biology, Chemistry and Health Science, Manchester Metropolitan University, Manchester, United Kingdom, 5Department of Neurology, Hospital Mutua de Terrassa, Terrassa, Spain


1. Abstract
2. Introduction
3. Material and methods
3.1. Patient recruitment
3.2. FDG-PET and CT brain scans
3.3. Study interpretation and analysis
3.4. Carotid specimens/histology/immunohistochemistry
3.5. Statistical Methods
4. Results
4.1. FDG ipsilateral uptake and plaque inflammation
4.2. FDG uptakes in ipsi- and contralateral carotid arteries
5. Discussion
6. Acknowledgment
7. References


It is not clear if 18FDG-PET can be useful for detection of inflammation in low to moderate carotid stenosis. We studied 15 patients scheduled for endarterectomy with contralateral carotids with less than 50% stenosis. 18-FDG-PET was performed prior to CEA and 3 months following surgery. FDG-uptake values were calculated based on maximum standardized uptake value (SUV) and corresponding uptake ratios. We confirmed by CD68 macrophage staining that FDG accumulation corresponds to active inflammation (R=0.8 p<0.005). We found significant correlation between the FDG-uptake in the carotids scheduled for CEA and contralateral carotids with low to moderate stenosis (R=0.9 p<0.001). The FDG uptake ratio in the contralateral arteries remained stable on the follow-up imaging (1.15+/-0.2 vs. 1.14+/-0.1; R=0.7 p=0.006). We did not find correlation between FDG uptake and symptomatic or asymptomatic patients, degree of carotid stenosis and vascular risk factors. This is a prospective, preliminary in vivo study demonstrating that low to moderate carotid atherosclerosis can be detected using 18-FDG-PET imaging and highlights the truly systemic nature of atherosclerosis.