Vascular Ultrasound - Exams

What Type of Vascular Ultrasound Evaluations are Performed?

Cerebrovascular Evaluation

Cerebrovascular disease is a group of brain dysfunctions related to disease of blood vessels supplying the brain. Hypertension is the most important cause that damages the blood vessel lining endothelium, exposing the underlying collagen where platelets aggregate. Sustained hypertension permanently changes the architecture of the blood vessels making them narrow, stiff, deformed and uneven which are more vulnerable to fluctuations of blood pressure.

A cerebrovascular evaluation uses noninvasive ultrasound to examine the blood flow to the brain. As blood leaves the heart via the aorta, it circulates up through the carotid and vertebral arteries on each side of the neck to the head.

During a cerebrovascular evaluation the technologist will pass a transducer (probe) over your neck. The test includes examination of the subclavian, vertebral, internal and external carotid arteries. This noninvasive test is used to detect and quantify the degree of obstruction, which may have formed in any of the arteries listed above from a build-up of cholesterol or fatty material called plaque. This build-up, referred to as atherosclerosis, increases an individual's risk for stroke.

Length of exam: 45 min – 60 min

Symptoms: Stroke, transient ischemic attack, bruit, syncope, abnormal gait, limb paralysis, paresthesia, vertigo, difficulty speaking, sudden visual loss, difficulty swallowing, etc. Preparation: None

Carotid Intima-Media

1999 study published in the New England Journal of Medicine concluded that increases in the thickness of the intimal and medial layers of the carotid artery are directly associated with an increased risk of heart attack and stroke. By measuring the thickness of the patient’s arteries, we are given a glimpse of his/her overall risk of developing cardiovascular disease. Carotid intima-media thickness (IMT) exams have also been found to be useful at tracking changes in the carotid wall thickness after medication or lifestyle changes have been prescribed. Multiple studies have demonstrated a regression in the IMT over time after the implementation of cholesterol-lowering medication.

In an effort to reduce the number of cardiovascular events and promote prevention within the community, Northwest Vascular Diagnostics is pleased to be offering carotid IMT exams. All outpatients who are referred for a carotid ultrasound will now receive a carotid IMT measurement at no additional cost.

Upper Extremity Arterial Evaluation

Arterial segmental pressure and waveform evaluations are performed to evaluate the upper extremity arteries to determine the presence, severity, and location of arterial occlusive disease or absence of pathology. Duplex ultrasonography will be performed if clinically indicated. Thoracic Outlet Syndrome, Raynauds and Allen’s tests are specialty exams that are performed and are listed in the following paragraphs.

Length of exam: 45 – 60 min

Symptoms: Arterial insufficiency, limb ischemia/digital ischemia. Preparations: None

Lower Extremity Arterial Evaluation

Some of the common indications for performance of lower extremity arterial duplex imaging include:

• Assessment of patients with known arterial disease
• Pre-procedure assessment for planning of an intervention
• Follow-up to determine technical adequacy surgical intervention, i.e. post angioplasty and/or stent placement
• Evaluation of aneurysm, pseudoaneurysm, arterial-venous fistula
• Evaluation of arterial trauma

The initial test to identify disease or normality of the arteries in the lower extremity is an ankle-brachial index (ABI). This is a physiologic test that identifies blood pressures and arterial waveforms in both lower extremities and compares them to the brachial blood pressures.

If the physiologic test is determined to be abnormal, a second test to evaluate arterial disease will be performed. This second test will include duplex imaging of the arteries in the lower extremities.

Duplex ultrasonography of the lower extremity arteries is performed to provide an overview of the location, extent and severity of vascular disease. The ultrasound evaluation can be performed from the abdominal aorta through the tibial vessels and extended into the foot in order to facilitate clinical management decisions.

Length of exam: 45 – 60 min

Symptoms: Claudication, ischemic rest pain, arterial ulcerations. Preparations: None

Upper and Lower Extremity Vein Evaluation

Deep vein thrombosis (DVT) is a condition in which a blood clot forms in one of the deep veins in the body. This condition is most commonly found in the lower leg or thigh, however it can also form in the upper extremities. One of the major complications of lower extremity DVT is the traveling of the blood clot to the lungs (Pulmonary Embolism), brain, or heart, leading to severe damage.

Some of the major risk factors for developing a DVT include sitting for a long period of time (long plane or car trips), bedrest, recent surgery, hormone medications, oral contraceptives, cigarette smoking, obesity, hypercoagulability disorders, cancerous tumors, and pregnancy.

Lower Extremity:

A duplex ultrasound of the deep veins in the lower extremities is performed to determine the presence or absence of deep vein thrombosis (DVT) using compression and augmentation maneuvers. The superficial veins are also examined to determine patency and valve competence.

Upper Extremity:

A duplex ultrasound of the deep veins in the upper extremities is performed to determine the presence or absence of deep vein thrombosis (DVT) using compression and augmentation maneuvers. The superficial veins are also evaluated for patency.

Length of exam: 45 – 60 min

Symptoms: Pain in limb, limb swelling, superficial mass/lump, shortness of breath, pulmonary embolism, chest pain with respirations, ulcer/skin changes. Preparation: None