Vascular Laboratory

Vascular Imaging is an integral part of the diagnostic work up of arterial and venous disease. This may involve one or more of the following non-invasive tests. The Milford Vascular Institute has an on-site Vascular Laboratory with a dedicated, full-time registered Ultrasound Technologist available Monday through Friday. All of the exams are either performed at our office or arranged for you through our office.

ABI

The ankle-brachial index (ABI) is a simple, reliable means for diagnosing peripheral arterial disease (PAD). Blood pressure measurements are taken at the arms and ankles using a pencil shaped ultrasound device called a Doppler. A Doppler instrument produces sound waves (not x-rays) and is considered noninvasive because it does not require the use of needles or catheters. The ABI test is performed in our vascular laboratory.

Although the ABI is extremely reliable, this test may not be accurate in all patients. Some patients with long-standing diabetes, kidney disease, or some elderly patients, may have rigid blood vessels. These may be difficult to compress with the blood pressure cuff and, in these patients, the ABI reading may not be accurate

An ABI value greater than 0.80 is rarely associated with short-term leg problems such as foot wounds or amputation. Nevertheless, any evidence of PAD (where the ABI measurement is less than 1.00) is associated with future risk of heart attack and/or stroke.

An ABI value between 0.40 – 0.80 is moderately decreased and such patients often experience some symptoms such as pain in the legs. Attention to foot care is extremely important to prevent accidental injury or infection. Again, any evidence of PAD is associated with future risk of heart attack and/or stroke! Serious efforts to keep one’s risk factors under control are essential to keep PAD from getting worse.

An ABI value of less than 0.40 indicates severe PAD. Patients should be extremely careful to avoid any foot injuries. Proper foot care may prevent development of non-healing wounds, rest pain, or even gangrene. The physicians at Milford Vascular Institute will evaluate the risk and benefits to improve leg blood flow through endovascular methods or surgery.

Duplex Ultrasound

Duplex ultrasound combines Doppler flow information and conventional imaging information, sometimes called B-mode, to allow physicians to see the structure of your blood vessels. Duplex ultrasound shows how blood is flowing through your vessels and measures the speed of the flow of blood. It can also be useful to estimate the diameter of a blood vessel as well as the amount of obstruction, if any, in the blood vessel.

Conventional ultrasound uses painless sound waves higher than the human ear can detect that bounce off of blood vessels. A computer converts the sound waves into two-dimensional, black and white moving pictures called B-mode images.

Doppler ultrasound measures how sound waves reflect off of moving objects. A wand bounces short bursts of sound waves off of red blood cells and sends the information to a computer. Doppler ultrasound produces two-dimensional color images that show if blood flow is affected by problems in the blood vessels, such as cholesterol deposits.

When performing duplex ultrasound, your physician uses the two forms of ultrasound together. The conventional ultrasound shows the structure of your blood vessels and the Doppler ultrasound shows the movement of your red blood cells through the vessels. Duplex ultrasound produces images that can be color coded to show physicians where your blood flow is severely blocked as well as the speed and direction of blood flow.

The physicians at Milford Vascular Institute may recommend a duplex ultrasound to help diagnose and examine conditions that affect the blood vessels, such as Carotid Artery Disease, Abdominal Aortic Aneurysmal disease (AAA), Peripheral Arterial Disease (PAD), and venous disease (DVT, Varicose Veins, Chronic Venous Insufficiency).

CT Angiography (CTA)

Computerized tomographic angiography, also called CT angiography or CTA, is a test that combines the technology of a conventional CT scan with that of traditional angiography to create detailed images of the blood vessels in the body.

In a CT scan, x rays and computers create images that show cross-sections, or slices, of your body. Angiography involves the injection of contrast dye into a large blood vessel, usually in your leg, to help visualize the blood vessels and the blood flow within them. When the contrast dye is used to visualize your veins, the study is called a venogram, and when it is used to visualize your arteries, it is known as an arteriogram. CT angiography is similar to a CT scan, but the contrast dye is injected into one of your veins shortly before the X ray image is performed. Because the dye is injected into a vein rather than into an artery, as in traditional angiography, CT is considered less invasive.

Your physician may order CT angiography to help diagnose a narrowing or obstruction of the arteries, an aneurysm, deep vein thrombosis, pulmonary embolism, or another vascular condition.

During the study, you will lie down on a table, which passes through a donut-shaped device. Inside the device, a machine takes x rays in arcs around the area of your body being examined. Tissues of varying densities absorb these x rays in varying amounts. The computer assigns these densities different numerical values and then plots an image based on these values, in shades of gray. During the CT angiogram, a dose of contrast dye will be injected into one of your veins. As the dye flows through your circulatory system, it will highlight your blood vessels on the scan. A computer will produce 3-dimensional (3D) images of your blood vessels from the x ray images.

MRA

MRI (magnetic resonance imaging) uses magnetic fields and radio waves to produce two-dimensional or three-dimensional images of the structures inside your body, such as your heart, brain or blood vessels. When this scanning method is applied to the blood vessels, it is also sometimes referred to as MRA (magnetic resonance angiography). The MRA equipment consists of a table that slides in and out of a donut-shaped machine. A computer attached to the machine processes radio waves and magnetic fields to create two-dimensional or three-dimensional images.

MRA not only helps the physicians at Milford Vascular Institute diagnose your condition, it also helps them plan treatment. MRA also may, in some circumstances, have advantages that other tests do not. For instance, MRA does not require X-ray exposure to detect narrowing of arteries, unlike computed tomography (CT) scans or angiograms.