Venous Duplex Imaging

About Deep Vein Thrombosis
Veins are divided into two groups based on the depth of their location: superficial veins, or veins just under the skin; and deep veins. Deep vein thrombosis (DVT) implies the development of a blood clot in a deep vein. These blood clots can break loose and travel to the lungs. This is a very serious situation and can be life threatening.

A blood clot in the lung arteries, known as pulmonary embolus, interferes with circulation and breathing. A blood clot can occur in any vein, but usually occurs in the leg veins.

Clots in the superficial veins usually stay localized and do not cause pulmonary embolus. These veins, however, are connected to the deep venous system, so clots from superficial veins can occasionally make their way into the deep veins of the legs.

Symptoms
Though DVT sometimes has no symptoms, common symptoms of DVT include:

• Pain
• Swelling
• Redness
• Warmth

Other symptoms may include:

• Shortness of breath
• Chest pain
• Spitting up blood

These symptoms may result from conditions other than pulmonary embolus, however, it is important for individuals with the above symptoms to be evaluated for the possibility of DVT.

Risk Factors

• Age over 40
• Obesity
• Immobilization
• Pregnancy
• Birth control pills
• History of previous DVT
• History of cancer
• Trauma to the leg or pelvis
• Post-surgical period
• Changes in clotting time

Warnings Signs

• Tired, heavy-feeling legs
• Leg pain from prolonged sitting or standing
• Swollen ankles at night
• Varicose or spider veins, especially during or after pregnancy
• Tingling, numbness, burning or cramping in legs and feet
• Discoloration of the skin
• Open sores or ulcers on the lower leg
• History of vein problems in the family

Reducing Risk Factors
It is possible to minimize risk factors for DVT and is particularly important for those who have had previous deep venous clots. To reduce your risk:

• In periods of long driving, make frequent stops and walk around.
• On plane rides, walk up and down the aisle and do frequent heel/toe lifts.
• If you are scheduled for surgery let your doctor know about any history of previous deep venous clots.
• Dehydration, or not enough water in your system, increases thickness of the blood, produces sluggish blood flow, and increases risk of clots. Alcoholic beverages produce dehydration.
• Wear compression stockings if you have had previous deep venous clots, if you have varicose veins or if you are pregnant.
• If you take birth control pills, refrain from smoking.

Venous Duplex Imaging
Venous duplex imaging is commonly used in diagnosing DVT. This test consists of ultrasound or sound wave imaging of the veins and evaluation of blood flow through the veins with a Doppler.

The procedure involves the application of gel to the skin and placement of an ultrasound probe over the area to be examined. Gentle pressure is applied with the probe to detect any presence of clots in the veins. Normally, this does not result in any pain, but you may feel some discomfort. The test is recorded on a videocassette for physician interpretation and as a permanent record.

The study may be repeated in a few days to see if there is any progression of the clot through the communicating veins into the deep venous system.

Preparation
There are no special preparations for the procedure. The test takes approximately one hour to complete.

Results
If your procedure is positive for DVT, your physician will be called upon completion of exam. Written results of the procedure are also provided to your physician within five to seven work days. You may wish to contact your physician to discuss your results.

Treatment
The type of treatment you receive depends on where the clot is located and the likelihood of complications occurring. When deep venous thrombosis (DVT) or clots are suspected or documented, you may be admitted to the hospital under the care of your doctor. Blood thinner (heparin) is usually given to prevent further clotting.

Superficial vein clots are usually self-limiting and need local treatment without any hospitalization.