The central goal of our research is to reduce complications from atherosclerotic disease through the development of imaging technologies. We have previously developed an extensive capability to investigate carotid atherosclerosis via magnetic resonance imaging (MRI). However, our studies have also shown that some aspects of atherosclerotic disease are not easily imaged by MRI, leading us to pursue a multimodality imaging strategy. Most notably, positron emission tomography (PET) scanning offers the possibility to use molecular tracers such as FDG in human studies of atherosclerosis. Thus, combining the capabilities of MRI and PET imaging may offer a more complete picture of atherosclerotic plaque biology. Despite the promise of FDG-PET imaging, considerable challenges exist, most notably related to spatial resolution. Therefore, our central motivation in this proposal is to develop a technique that leverages the high-resolution morphological and perfusion information of MRI to help differentiate the source of FDG-PET signals in carotid atherosclerosis. To investigate this concept, we will utilize high-resolution micro-PET imaging to establish a gold standard of localized signal in ex vivo carotid endarterectomy (CEA) specimens.
In order for vessel wall imaging methods to meet the clinical need for improved stratification of risk in patients with established lesions of atherosclerosis, those methods must address the underlying pathology that leads to those events. While magnetic resonance imaging provides exceptional information on atherosclerotic plaque morphology, positron emission tomography may be better suited for evaluation of plaque biology, particularly inflammation. The goal of this proposal is to develop a quantitative, reliable, and comprehensive combined MRI PET approach for characterizing carotid artery plaque and inflammation.