In Vivo 18F-Fluorodeoxyglucose Positron Emission Tomography Imaging Provides a Noninvasive Measure of Carotid Plaque Inflammation in Patients

• Published in: Journal of the American College of Cardiology 2006-11, Vol.48 (9), p.1818-1824
• Main Authors: Tawakol, Ahmed, Migrino, Raymond Q., Bashian, Gregory G., Bedri, Shahinaz, Vermylen, David, Cury, Ricardo C., Yates, Denise, LaMuraglia, Glenn M., Furie, Karen, Houser, Stuart, Gewirtz, Henry, Muller, James E., Brady, Thomas J., Fischman, Alan J.
• Format: Article
• Language: English
• Subjects: Aged; Atherosclerosis - diagnosis; Atherosclerosis - diagnostic imaging; Atherosclerosis - pathology; Biological and medical sciences; Blood pressure; Cardiology; Cardiology. Vascular system; Carotid Stenosis - diagnosis; Carotid Stenosis - diagnostic imaging; Carotid Stenosis - pathology; Female; Fluorodeoxyglucose F18; Histology; Humans; Inflammation - diagnosis; Inflammation - diagnostic imaging; Macrophages - diagnostic imaging; Macrophages - pathology; Male; Medical imaging; Medical research; Medical sciences; Middle Aged; Patients; Positron-Emission Tomography - methods; Studies; Veins & arteries
• ISSN: 0735-1097; 1558-3597
• DOI: 10.1016/j.jacc.2006.05.076

In Vivo 18F-Fluorodeoxyglucose Positron Emission Tomography Imaging Provides a Noninvasive Measure of Carotid Plaque Inflammation in Patients Ahmed Tawakol, Raymond Q. Migrino, Gregory G. Bashian, Shahinaz Bedri, David Vermylen, Ricardo C. Cury, Denise Yates, Glenn M. LaMuraglia, Karen Furie, Stuart Houser, Henry Gewirtz, James E. Muller, Thomas J. Brady, Alan J. Fischman Seventeen subjects scheduled for carotid endarterectomy underwent fluorodeoxyglucose positron emission tomography (FDG-PET) imaging of their carotid plaques within 1 month of surgery. Subsequently, the FDG-PET signal within the plaques was compared with the macrophage staining of the carotid specimens. There was a significant correlation between the in vivo PET signal and the macrophage staining from the corresponding carotid specimen (r = 0.85; p < 0.0001). These data establish that FDG-PET can be used to noninvasively assess carotid plaque inflammation. If natural history studies link increased carotid FDG-PET activity with clinical events, this imaging approach may improve risk stratification of patients with carotid atherosclerosis. Given the importance of inflammation in atherosclerosis, we sought to determine if atherosclerotic plaque inflammation could be measured noninvasively in humans using positron emission tomography (PET). Earlier PET studies using fluorodeoxyglucose (FDG) demonstrated increased FDG uptake in atherosclerotic plaques. Here we tested the ability of FDG-PET to measure carotid plaque inflammation in patients who subsequently underwent carotid endarterectomy (CEA). Seventeen patients with severe carotid stenoses underwent FDG-PET imaging 3 h after FDG administration (13 to 25 mCi), after which carotid plaque FDG uptake was determined as the ratio of plaque to blood activity (target to background ratio, TBR). Less than 1 month after imaging, subjects underwent CEA, after which carotid specimens were processed to identify macrophages (staining with anti-CD68 antibodies). There was a significant correlation between the PET signal from the carotid plaques and the macrophage staining from the corresponding histologic sections (r = 0.70; p < 0.0001). When mean FDG uptake (mean TBR) was compared with mean inflammation (mean percentage CD68 staining) for each of the 17 patients, the correlation was even stronger (r = 0.85; p < 0.0001). Fluorodeoxyglucose uptake did not correlate with plaque area, plaque thickness, or area of smooth muscle cell staining. We established tha