Private DVT Scan London: Deep Vein Thrombosis Ultrasound — Swollen Leg, Blood Clot Check, Same-Day Results

Deep vein thrombosis is a blood clot that forms in a deep vein, most commonly in the leg. It affects approximately 1 in every 1,000 people in the UK each year, according to the NHS. DVT is not merely uncomfortable — an untreated clot can break loose and travel to the lungs, causing a pulmonary embolism (PE), which can be life-threatening.

If your leg is swollen, painful, warm, or red — particularly after a long flight, period of immobility, surgery, or if you have risk factors like a personal or family history of blood clots — you need to know whether a DVT is present. And you need to know quickly.

A private DVT scan at The Wellness London gives you an answer the same day. A GMC-registered doctor performs compression ultrasound with Doppler assessment of your leg veins, interprets findings in real time, and tells you whether a clot is present before you leave the clinic. If DVT is confirmed, your doctor immediately advises on the next steps — including urgent referral for treatment if needed.

Worried about a blood clot? Message us on WhatsApp now or email team@thewellnesslondon.com. We prioritise urgent requests.

What Is Deep Vein Thrombosis?

DVT occurs when a blood clot forms within a deep vein, usually in the calf, thigh, or pelvis. The clot partially or completely blocks blood flow through the vein, causing the leg to swell, become painful, and sometimes change colour.

The danger of DVT is not the leg symptoms alone — it is the risk of pulmonary embolism. If part of the clot breaks off and travels through the bloodstream to the lungs, it can block blood flow and become a medical emergency. The NHS estimates that pulmonary embolism causes approximately 25,000–32,000 deaths per year in England.

This is why DVT requires prompt diagnosis. The difference between "it is just a swollen leg" and "you have a blood clot that needs immediate treatment" can only be determined by imaging.

Symptoms of DVT

DVT can present with one or more of the following symptoms, typically in one leg:

Swelling. Unilateral leg swelling is one of the most common presenting symptoms. The affected leg may be noticeably larger than the other.

Pain. Often described as a deep ache or cramping sensation in the calf or thigh. Pain may worsen when standing or walking.

Warmth. The affected area may feel warm to the touch compared to the other leg.

Redness or discolouration. The skin over the affected area may appear red, bluish, or have a different colour than the other leg.

Tenderness. The leg may be tender when squeezed, particularly along the path of the deep veins.

Important: Some DVTs are asymptomatic — they cause no symptoms at all and are discovered incidentally. Conversely, the symptoms listed above can also be caused by conditions other than DVT (muscle strain, Baker's cyst, cellulitis, lymphoedema). This is why imaging is essential — symptoms alone cannot confirm or rule out DVT.

Risk Factors for DVT

You are at higher risk of developing DVT if you have:

• Recently had surgery, particularly hip, knee, or abdominal surgery
• Been immobile for a prolonged period — long-haul flights (4+ hours), hospital bed rest, or leg immobilisation (cast, splint)
• A personal or family history of DVT or pulmonary embolism
• Active cancer or cancer treatment
• A known clotting disorder (thrombophilia, Factor V Leiden, antiphospholipid syndrome)
• Recently been pregnant or postpartum (risk is elevated for 6 weeks after delivery)
• Been taking the combined oral contraceptive pill or hormone replacement therapy (HRT)
• Obesity (BMI over 30)
• Varicose veins
• Age over 60
• Recent leg injury or trauma
• Dehydration
• Smoking

Having one or more of these risk factors combined with leg symptoms should prompt urgent investigation.

Have symptoms and risk factors? Book an urgent DVT scan on WhatsApp.

How a DVT Scan Works

A DVT scan uses two complementary ultrasound techniques:

Compression ultrasound. The doctor places the ultrasound probe over each segment of the deep venous system (from the common femoral vein in the groin to the popliteal vein behind the knee, and the calf veins) and applies gentle downward pressure. A normal vein compresses completely under pressure — it collapses flat. A vein containing a blood clot does not compress — it remains round or partially open, indicating a clot is present. This technique has a sensitivity of 94–97% for proximal DVT.

Colour Doppler. Blood flow through the veins is assessed using colour Doppler imaging. Normal veins show colour flow that changes with respiration and calf squeeze. Absent or reduced flow suggests obstruction by a clot.

The scan also assesses the superficial veins for thrombosis (superficial vein thrombophlebitis), which, while generally less dangerous than DVT, can extend into the deep system and may require treatment.

DVT Scans at The Wellness London: Pricing

All prices include the doctor-performed scan, verbal debrief, and same-day written report.

What to Expect During Your DVT Scan

No preparation is needed. No fasting. Wear loose-fitting trousers or shorts that can be rolled up above the knee, or you will be provided with a gown.

You will lie on a comfortable examination bed. The doctor applies warm ultrasound gel and systematically examines the deep veins from the groin to the ankle, applying gentle compression at multiple points along the venous system. You may be asked to flex your foot or the doctor may squeeze your calf to assess blood flow response (augmentation).

The scan takes approximately 20–30 minutes for a single leg and 30–45 minutes for bilateral assessment.

Because a GMC-registered doctor performs your scan at The Wellness, the result is available immediately. Your doctor will tell you during the scan whether a clot is present, explain the extent and location of any clot found, and discuss the urgency and nature of treatment required.

What Happens If DVT Is Confirmed?

If your scan confirms DVT, your doctor will:

Explain the finding clearly. You will be told where the clot is located, how extensive it is, and what this means clinically.

Advise on urgency. Proximal DVT (thigh-level) carries higher risk of pulmonary embolism than isolated calf vein DVT, and treatment urgency reflects this.

Facilitate immediate referral. Your doctor can arrange same-day referral to the appropriate medical team for anticoagulation therapy (blood thinners). In some cases, your doctor may advise attending A&E directly for immediate treatment initiation. A written report is provided for the receiving team.

Provide a same-day written report. Your report is issued within two hours and can be shared electronically with your GP or any other treating doctor.

DVT treatment typically involves anticoagulation medication (blood thinners) for a minimum of 3–6 months. Your scan report provides the treating team with the information they need to initiate treatment immediately.

What If the Scan Is Normal?

A normal DVT scan is highly reassuring. Compression ultrasound has excellent sensitivity for proximal DVT, meaning a normal scan significantly reduces the probability of a clinically significant blood clot.

Your doctor will explain the normal findings, discuss alternative causes for your symptoms (muscle strain, Baker's cyst, lymphoedema, cellulitis), and advise on whether any further investigation is needed.

If your clinical suspicion remains high despite a normal scan (for example, persistent symptoms with significant risk factors), your doctor may recommend a repeat scan in 5–7 days or further investigation.

DVT After Flying: Travel-Related Blood Clots

Long-haul flights (4 or more hours) are a well-recognised risk factor for DVT, often referred to as "economy class syndrome" — though DVT can occur in any class of travel. Prolonged sitting in a cramped position reduces venous return from the legs and increases clot risk.

If you have recently taken a long flight and are experiencing leg swelling, calf pain, or warmth in one leg, a DVT scan can provide rapid reassurance or early diagnosis. Early treatment significantly reduces the risk of complications.

Recently flown and experiencing leg symptoms? Book a DVT scan on WhatsApp.

Frequently Asked Questions

Is a DVT scan painful? No. The compression technique involves gentle pressure — you may feel mild discomfort if your leg is already tender, but the scan is not painful.

How quickly can I get an appointment? Same-day and next-day appointments are available. For urgent concerns, contact us directly and we will prioritise your booking.

Do I need a referral? No. Book directly without a GP referral.

Can DVT occur in both legs? Yes, though bilateral DVT is less common. If you have symptoms in both legs, a bilateral scan is recommended.

Should I go to A&E instead? If you are experiencing chest pain, sudden breathlessness, or coughing up blood alongside leg symptoms, call 999 immediately — these may indicate pulmonary embolism. For leg symptoms without chest symptoms, a private DVT scan provides rapid diagnosis without the long wait times often experienced in A&E.

Book Your DVT Scan

📱 Book via WhatsApp

📧 Email: team@thewellnesslondon.com

🌐 Book online: thewellnesslondon.com/ultrasound

This article was reviewed by the clinical team at The Wellness London. All scans are performed by GMC-registered doctors. Last updated March 2026.

Medical disclaimer: This information is for educational purposes and does not replace professional medical advice. If you are experiencing chest pain, sudden breathlessness, or coughing up blood alongside leg swelling, call 999 immediately.