Ultrasound Scan:
Lower Limb
Deep Vein Thrombosis (DVT) 

Deep vein thrombosis (DVT) is a condition characterised by the formation of a blood clot, or thrombus, in the deep veins of the body, commonly in the legs. It typically occurs when blood flow is slowed or restricted, leading to the accumulation of blood and the formation of a clot within a deep vein. DVT can occur in any deep vein, but it most commonly affects the veins in the calf or thigh. These veins include the common femoral vein, profunda femoris vein, femoral vein, popliteal vein, medial and lateral gastrocnemius veins, posterior tibial veins, peroneal veins, anterior tibial veins and soleal veins. The condition can be serious because if the blood clot dislodges and travels through the bloodstream, it can reach the lungs and cause a potentially life-threatening condition called pulmonary embolism.

This scan usually takes between 15-20 minutes to complete.

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The purpose of this ultrasound is to assess for blood clots (DVT). This ultrasound requires direct contact with your skin. A DVT scan can be done to asses for blood clots in the leg, arm and abdomen (iliocaval) veins.

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The scan starts at the groin crease and the entire leg is scanned down to the ankles. We will require you to remove your shoes, trousers/shorts and we will provide you with a disposable gown. Dresses and skirts don't need to be removed and can be lifted out of the way.

We will ask for you to lie down on the examination bed to assess the thigh and sitting up with your legs over the edge of the bed to assess the calf. During the scan we will apply ultrasound gel to your legs and use the ultrasound machine to look for clots. We will need to periodically compress the calf and thigh to assess for DVT.

Ultrasound is a quick and non-invasive way to assess for blood clots with results available immediately after the scan. An ultrasound can also help determine the size and location of the clot, as well as monitor the effectiveness of treatments for the DVT. A leg deep vein thrombosis (DVT) ultrasound, also known as a venous duplex ultrasound, is a common imaging test used to diagnose DVT. Here's why a leg DVT ultrasound is performed:

Diagnosis of DVT

The primary purpose of a leg DVT ultrasound is to detect the presence of a blood clot in the deep veins of the leg. Ultrasound imaging can visualise the veins and identify the location and extent of the clot.

Differential diagnosis

Leg swelling and pain can have various causes, and not all cases are due to DVT. Ultrasound helps distinguish DVT from other conditions that may present with similar symptoms, such as muscle strains, cellulitis, or superficial thrombophlebitis.

Assessment of clot size and location

The ultrasound can determine the size and location of the blood clot within the deep veins. This information is essential for determining the appropriate treatment approach.

Evaluation of blood flow

Ultrasound can assess the blood flow in the affected veins. In DVT, the flow may be obstructed by the clot, causing abnormal blood flow patterns. Evaluating blood flow helps assess the severity of the clot and guides treatment decisions.

Follow-up monitoring

After initial diagnosis and treatment of DVT, ultrasound may be performed periodically to monitor the progression or resolution of the clot. It can help determine if further treatment adjustments are necessary.

Ultrasound is often the preferred imaging modality for diagnosing DVT due to its accessibility, accuracy, and lack of radiation exposure. It is a relatively quick and painless procedure that can be performed at the bedside or in an imaging center.

Deep vein thrombosis (DVT) is influenced by various risk factors that increase the likelihood of developing the condition. These risk factors can be categorised into two main groups: acquired risk factors and inherited or genetic risk factors. Here are common risk factors associated with DVT:

Acquired Risk Factors:

1. Prolonged immobility: Extended periods of immobility, such as during long flights, prolonged bed rest, or sitting for long periods, can increase the risk of DVT. Immobility slows blood flow, making it more likely for blood to pool and clot.

2. Recent surgery or hospitalisation: Major surgical procedures, especially those involving the lower extremities or abdomen, increase the risk of DVT. Hospitalisation itself, particularly in individuals with additional risk factors, can also contribute to the development of blood clots.

3. Trauma or injury: Trauma, such as fractures, severe muscle injuries, or trauma that affects blood vessels, can increase the risk of DVT.

4. Cancer and its treatments: Certain types of cancer, particularly those involving the abdomen, pelvis, or lymphatic system, increase the risk of DVT. Cancer treatments like chemotherapy can also affect blood clotting.

5. Hormonal factors: Hormonal changes, such as those during pregnancy, use of oral contraceptives (birth control pills), hormone replacement therapy, or certain fertility treatments, can increase the risk of DVT.

6. Obesity: Excess body weight puts additional pressure on veins, making blood flow more sluggish and increasing the risk of clot formation.

Inherited or Genetic Risk Factors:

1. Family history: Having a first-degree relative (parent, sibling) who has had DVT or pulmonary embolism increases the risk of developing DVT.

2. Inherited clotting disorders: Certain genetic disorders, such as factor V Leiden mutation, prothrombin gene mutation, or deficiencies in natural anticoagulants like protein C, protein S, or antithrombin, can predispose individuals to abnormal blood clotting and increase the risk of DVT.

3. Age: The risk of DVT increases with age, with older individuals being more susceptible.

4. Personal history of DVT: A previous history of DVT increases the risk of developing another episode in the future.

5. Other medical conditions: Certain medical conditions, such as heart failure, chronic kidney disease, inflammatory bowel disease, and autoimmune disorders, can increase the risk of DVT.

It's important to note that having one or more risk factors doesn't necessarily mean that an individual will develop DVT. However, having these risk factors increases the likelihood, and some combinations of risk factors can further elevate the risk. If you have any concerns about your risk of DVT, it is advisable to consult with a healthcare professional who can assess your individual risk profile and provide appropriate guidance and preventive measures.

The symptoms of leg deep vein thrombosis (DVT) can vary, and not everyone with DVT will experience noticeable symptoms. However, common signs and symptoms to watch for include:

Leg pain

DVT often causes pain or tenderness in the affected leg. The pain can range from a mild ache to severe discomfort.

Swelling

DVT can cause swelling in the affected leg, particularly in the calf, ankle, or foot. The swelling may be accompanied by warmth or redness in the affected area.

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Warmth and redness

The skin over the affected vein may feel warm to the touch and appear red or discoloured.

Visible veins

Sometimes, the affected veins may become more prominent or visible through the skin.

Leg fatigue or heaviness

DVT can cause a sensation of fatigue or heaviness in the leg, making it difficult to walk or stand for prolonged periods.

It's important to note that these symptoms are not specific to DVT and can be caused by other conditions as well. Additionally, some individuals may have DVT without experiencing any noticeable symptoms. Therefore, it's crucial to seek medical evaluation if you have any concerns or if you suspect you may have DVT, especially if you have risk factors such as recent surgery, prolonged immobility, or a family history of blood clots.

If we find a DVT we will advise you of this finding at the time of your scan. We will ask you to wait while we contact your referring doctor to find out what they would like to do. Depending on the location of the blood clot usually determines whether treatment is required or not. In most cases, surveillance scans to keep an eye on any changes will be organised by your doctor. Your doctor may or may not organise a script for blood thinning medication. In rare cases we may advise you to present to the emergency department of your local hospital. If your referring doctor would like to see you on the same day as your scan or we request you attend the emergency department, we will provide you with a printed version of the ultrasound worksheet and written report so you are able to show this to any healthcare provider you may end up seeing. The worksheet and report will be sent to your referring doctor before you leave our rooms as well.

The treatment for leg deep vein thrombosis (DVT) typically involves a combination of medications and lifestyle modifications. The primary goals of treatment are to prevent the clot from growing larger, prevent new clots from forming, and reduce the risk of complications such as pulmonary embolism. The specific treatment plan may vary based on individual factors and the severity of the condition. Some common approaches include:

Anticoagulant medications

These medications, often referred to as blood thinners, are the cornerstone of DVT treatment. They help prevent the existing blood clot from growing and reduce the risk of new clots forming. Anticoagulants may be given intravenously or taken orally, and the duration of treatment can vary depending on the individual's circumstances.

Compression stockings

Wearing compression stockings helps to improve blood flow in the legs and reduce swelling. These stockings provide graduated pressure, which is tighter at the ankles and gradually decreases up the leg. Compression stockings can help alleviate pain and discomfort associated with DVT.

Ambulation and leg elevation

Staying mobile and regularly moving the legs can help prevent blood from pooling and reduce the risk of complications. Walking and engaging in gentle leg exercises are encouraged. Additionally, elevating the legs while sitting or lying down can help improve blood flow.

IVC filters

In some cases, if there is a high risk of pulmonary embolism and anticoagulant therapy is contraindicated or insufficient, an inferior vena cava (IVC) filter may be inserted. The IVC filter is a small device placed in the main vein of the abdomen to catch any clots that may break loose from the leg veins and prevent them from reaching the lungs.

Thrombolysis or thrombectomy

In certain situations, especially when the clot is extensive or causing severe symptoms, more aggressive interventions may be required. Thrombolysis involves administering clot-dissolving medications directly into the affected vein to break down the clot. Thrombectomy is a surgical procedure in which the clot is physically removed using special tools.

It's important to note that the specific treatment plan should be determined by a healthcare professional who will consider individual factors such as the location and extent of the clot, the presence of any underlying conditions, and the patient's overall health. Treatment for DVT should always be guided by a medical professional to ensure appropriate management and minimize the risk of complications.