Low enrollment due to inclusion/exclusion criteria

The purpose of this study is to determine the accuracy of a new non-invasive device, the Carotid Stenotic Scan (CSS), to check for stenosis of the internal carotid artery (ICA) as compared to a carotid ultrasound study.

Currently, carotid duplex ultrasound is used for screening for ICA stenosis and must be performed by a trained and certified vascular technologist using advanced duplex imaging equipment and with subsequent interpretation by a trained physician. It would be of value to develop an accurate, reliable, low-cost, and easily accessible tool to screen for extra-cranial ICA disease in an office based setting. However, such a tool would require novel technology that allows for quick, accurate, reproducible, and safe evaluation.

This study will evaluate a new technology called the Carotid Stenotic Scan (CSS) developed by CVR Global. The CSS instrument uses principles of cardiovascular resonance to detect low frequency pressure fluctuations associated with flow disturbances in areas of significant arterial narrowing.

Subjects will undergo a clinically ordered clinical carotid duplex ultrasound as part of standard of care. Subjects will have a noninvasive CSS assessment before or after the carotid duplex ultrasound.

Within 3 months following the date of the initial study visit, the electronic medical record will be queried for any interval correlative imaging studies (CTA, MRA, or angiography) and reports performed up to 1 month prior and 3 months after the duplex examination date. Report of findings will be documented (i.e., % ICA stenosis by CTA/MRA).

Inclusion Criteria:

• Outpatients age > 18 years sent to the vascular laboratory for carotid duplex examination for initial carotid ultrasound study or for follow-up of known carotid disease.
• Enrolled patients will include at least 100 subjects with at least moderate known stenosis (50-69% or greater, PSV > 125 cm/sec) or occlusion of one or both ICAs
• Up to 25 patients with known fibromuscular dysplasia (FMD) of the internal carotid arteries.

Exclusion Criteria:

• Age < 18 years.
• Hospitalized inpatients.
• Inability to provide informed consent.
• Prior history of carotid endarterectomy or carotid artery stent.
• Prior neck surgery
• Known prosthetic heart valve, known critical aortic stenosis, or study indication "preop" open heart or aortic surgery.

The study population will consistent of adult patients (> 18 years) presenting to the Cleveland Clinic Non-Invasive Vascular Laboratory for a scheduled carotid duplex ultrasound to evaluate for carotid artery disease or in follow-up of known ICA stenosis.