Current research in the neurovascular imaging research program focuses on:
- Carotid artery vessel wall imaging
- Carotid atherosclerotic plaque characterization
- Intracranial artery vessel wall imaging
- Imaging characterization of ischemic stroke patients
- Cerebral venous sinus thrombosis imaging
- Quantitative image analysis for atherosclerotic plaques
Multicontrast Atherosclerosis Characterization for Carotid Atherosclerotic Plaques
Carotid atherosclerotic disease (CAD) is a degenerative disease of the arterial wall caused by the buildup of fatty substances and cholesterol deposits. Disrupted atherosclerotic plaques can lead to transient ischemic attack and cerebral thromboembolic stroke, the leading cause of mortality and morbidity worldwide.
Current management guidelines for CAD are primarily based on the degree of luminal stenosis as determined by medical imaging, with high-grade (greater than 70 percent) stenosis as an indication for surgery or interventional procedures. However, the degree of stenosis may not be an accurate indicator of the severity of disease.
Characterization of so-called vulnerable plaque features, such as the presence of a large lipid-rich necrotic core with an overlying thin/ruptured fibrous cap, intraplaque hemorrhage and calcification can help better identify high-risk lesions. In this regard, magnetic resonance imaging (MRI) has shown unique strengths over other commonly used diagnostic imaging modalities that merely provide information on luminal stenosis.
The multicontrast atherosclerosis characterization (MATCH) technique employs a 3-D spoiled segmented fast low-angle shot readout to acquire data with three different contrast weightings following a nonselective inversion pulse and various inversion-recovery times. This is the first 3-D MRI technique that acquires spatially coregistered multicontrast image sets in a single scan for adequate characterization of carotid plaques (Figure 1).