Non-invasive Computer-Aided Phenotyping of Vasculopathy

Inclusion Criteria: Individuals must meet one of the following inclusion criteria in order to be eligible to participate in the study: * Case subjects will be patients with documented carotid atherosclerosis, scheduled for magnetic resonance or CT angiography and subsequent elective endarterectomy with 30 days of enrollment in the study * Case subjects will be patients with peripheral arterial disease (PAD) with clinical symptoms, scheduled for magnetic resonance or CT angiography and indicated endarterectomy of diseased areas of femoral arteries within 30 days of enrollment in the study Exclusion Criteria: * Subjects with claustrophobia or inability to tolerate prior MRI studies. * Subjects with metal implants that are not MRI compatible (LSU detailed checklist to be attached) including: Subjects with any type of bio-implant activated by mechanical, electronic, or magnetic means (e.g. cochlear implants, pacemakers, neurostimulators, biostimulators, electronic infusion pumps, etc.). Subjects with any type of ferromagnetic bio-implant that could potentially be displaced or damaged, such as aneurysm clips, metallic skull plates, etc. * Subjects with a history of kidney disease or dialysis that are unable to receive intravenous gadolinium contrast material. * Female subjects. A urine pregnancy test will be required of all female subjects of childbearing potential prior to inclusion in this study. Pregnant or nursing females will be excluded from the study. * Subjects who cannot adhere to the experimental protocol. * Subjects allergic to contrast material.