The Differences in Images of Vertebral Artery Stenosis and Carotid Artery Stenosis Pre- and Post-Percutaneous Transluminal Angioplasty and the Gene Expression Patterns in Peripheral White Blood Cells

The goals of this trial are:

1. To compare the sensitivity and specificity of various tools including Doppler and magnetic resonance imaging (MRI) for diagnosing vertebral artery stenosis and carotid artery stenosis. The positron emission tomography (PET)/MRI fusion imaging will be a promising tool to provide both anatomical and functional imaging for vulnerable plaques.
2. To identify patients at high risk of plaque rupture by image studies, biomedical profile, and gene expression of circulating monocytes.