A private vascular ultrasound-scan — also called a Doppler scan or duplex ultrasound — at Victoria Medical uses colour Doppler technology to assess blood flow through the arteries and veins in real time. It is the recommended first-line investigation for suspected deep vein thrombosis (DVT), carotid artery stenosis, peripheral arterial disease, and varicose vein assessment — without radiation and without a GP referral. Urgent same-day DVT scanning is available.
A swollen, painful leg after a long flight. A TIA that left you with a numb arm for an hour. Varicose veins that ache by the end of the day. These presentations share a common thread: the need for accurate vascular imaging to guide safe, timely management. A missed DVT can progress to pulmonary embolism. Undetected carotid stenosis carries a significant stroke risk. At Victoria Medical, we offer urgent same-day vascular Doppler scanning with a written report reviewed by Dr Xynopoulos available within 24 hours.
Our vascular sonographers are trained in duplex Doppler imaging and work in accordance with BMUS and British Society of Echocardiography guidelines. Where findings indicate a condition requiring specialist management — anticoagulation for DVT, carotid endarterectomy referral, or vascular surgery review — we can arrange a same-day cardiology or GP consultation at the clinic. We are at 170 Vauxhall Bridge Road, London SW1V 1DX — two minutes from Victoria Station.
Written & reviewed by
Dr Xynopoulos
MBBS, MRCP, GMC Registered — Specialist in Internal Medicine & Diagnostic Imaging · Reviewed by Victoria Medical Clinical Governance Team
What Is a Vascular Ultrasound-Scan?
A vascular ultrasound-scan combines two complementary technologies: B-mode (greyscale) imaging, which shows the structural anatomy of vessel walls and surrounding tissues, and Doppler imaging, which detects and quantifies blood flow. Colour Doppler maps the direction and velocity of flow within the vessel lumen, while spectral Doppler provides a waveform analysis that characterises flow patterns — distinguishing normal laminar flow from turbulent flow caused by stenosis or occlusion.
The term 'duplex ultrasound' refers to the simultaneous use of B-mode and Doppler imaging. It is the gold standard non-invasive investigation for most vascular conditions and is recommended by NICE, the British Society for Vascular Surgery, and the European Society for Vascular Surgery as the first-line investigation for DVT, carotid stenosis, and peripheral arterial disease.
Unlike CT angiography or MR angiography, vascular ultrasound-scan requires no contrast agents, no radiation, and no breath-holding. It can be performed at the bedside or in an outpatient setting, making it the most accessible and patient-friendly vascular imaging modality.
Vascular Scans We Offer
The table below summarises the vascular Doppler studies available at Victoria Medical, the conditions assessed, and the clinical relevance of each.
Urgent DVT scanning: If you have a swollen, painful, or red leg — particularly after a long journey, surgery, or immobility — contact us immediately. Same-day DVT assessment is available.
| Scan Type | Conditions Assessed | Clinical Relevance |
|---|---|---|
| DVT assessment (lower limb) | Deep vein thrombosis — femoral, popliteal, tibial, and calf veins; compression ultrasonography | Pooled sensitivity 90.1%, specificity 98.5% for proximal DVT (Bhatt et al., 2020); first-line investigation per NICE |
| Superficial vein mapping | Great saphenous vein (GSV) and small saphenous vein (SSV) reflux, varicose vein anatomy, perforator incompetence | Pre-operative mapping for varicose vein treatment; NICE NG168 recommends duplex before any intervention |
| Carotid artery Doppler | Internal carotid artery stenosis (NASCET criteria), plaque characterisation, vertebral artery flow | Carotid stenosis >50% is a high-risk criterion for stroke; sensitivity 91%, specificity 86% for any stenosis (Kordzadeh et al., 2022) |
| Peripheral arterial assessment | Ankle-brachial pressure index (ABPI), femoral, popliteal, and tibial artery stenosis or occlusion | ABPI <0.9 confirms peripheral arterial disease; waveform analysis characterises severity |
| Renal artery Doppler | Renal artery stenosis, renovascular hypertension, transplant kidney assessment | Indicated in hypertension refractory to treatment or with deteriorating renal function |
| Abdominal aortic aneurysm (AAA) | Aortic diameter measurement, aneurysm morphology | NICE recommends AAA screening for men aged 65+; diameter ≥5.5 cm requires surgical review |
DVT Assessment: Accuracy and the Evidence Base
Deep vein thrombosis (DVT) is a blood clot in the deep venous system, most commonly in the proximal veins of the lower limb — the femoral and popliteal veins. Untreated proximal DVT carries a risk of pulmonary embolism (PE) of approximately 50% if anticoagulation is not started. Accurate, timely diagnosis is therefore a clinical priority.
Compression ultrasonography (CUS) — in which the sonographer applies firm pressure to the vein with the probe to assess compressibility — is the cornerstone of DVT diagnosis. A non-compressible vein confirms DVT. A 2020 systematic review and meta-analysis in Blood Advances (Bhatt et al.) analysed 43 studies and reported pooled sensitivity of 90.1% (95% CI: 86.5–92.8%) and specificity of 98.5% (95% CI: 97.6–99.1%) for proximal compression ultrasonography. Whole-leg CUS achieved pooled sensitivity of 94.0% and specificity of 97.3%.
A 2021 review in the Journal of Clinical Medicine (Varrias et al.) confirmed that point-of-care compression ultrasound performed by trained clinicians has excellent diagnostic accuracy for acute proximal DVT, and is increasingly used in urgent and ambulatory settings. A 2024 systematic review in the Western Journal of Emergency Medicine (Hercz et al.) — analysing 15 publications, n = 2,511 examinations — reported pooled sensitivity of 90% and specificity of 95% for emergency physician-performed DVT ultrasound.
A 2020 systematic review in PLoS ONE (Kraaijpoel et al.) compared three CUS strategies — single limited, serial limited, and whole-leg — and found comparable failure rates across all three (1.0–1.9%). The choice between strategies is guided by pre-test probability, clinical context, and the relevance of isolated distal DVT.
Carotid Artery Doppler: Stroke Risk Assessment
The carotid arteries supply the majority of blood flow to the brain. Atherosclerotic plaque within the internal carotid artery (ICA) is a major modifiable risk factor for ischaemic stroke and transient ischaemic attack (TIA). Carotid duplex ultrasound is the recommended first-line investigation for patients with a history of TIA, minor stroke, or significant cardiovascular risk factors.
The scan measures the degree of ICA stenosis using the NASCET (North American Symptomatic Carotid Endarterectomy Trial) criteria, characterises plaque morphology (stable vs vulnerable), and assesses vertebral artery flow. Stenosis greater than 50% in a symptomatic patient is a high-risk criterion for recurrent stroke and triggers urgent referral for carotid endarterectomy or stenting.
A 2022 prospective study in Vascular (Kordzadeh et al.) evaluated AI-assisted duplex ultrasound for carotid artery disease in 156 patients and reported overall sensitivity of 91%, specificity of 86%, and accuracy of 92% for detecting any carotid artery stenosis. For stenosis greater than 75%, accuracy was 92%. The study demonstrated that duplex ultrasound is a reliable, accessible tool for carotid disease detection and risk stratification.
Varicose Vein Assessment and Superficial Vein Mapping
Varicose veins affect approximately 30% of the UK adult population. Beyond cosmetic concerns, symptomatic varicose veins cause aching, heaviness, skin changes, and — in advanced cases — venous ulceration. NICE guideline NG168 recommends duplex ultrasound as the mandatory pre-operative investigation before any varicose vein intervention.
The duplex scan maps the anatomy of the great saphenous vein (GSV) and small saphenous vein (SSV), identifies the site and extent of venous reflux (retrograde flow lasting more than 0.5 seconds on Valsalva or calf compression), and assesses perforator vein incompetence. This information directly determines the most appropriate treatment — endovenous laser ablation, radiofrequency ablation, foam sclerotherapy, or conventional surgery.
A superficial vein mapping scan at Victoria Medical produces a detailed report with reflux measurements and a diagram of the venous anatomy, which can be taken directly to a vascular surgeon or phlebologist for treatment planning.
How to Prepare for Your Vascular Ultrasound-Scan
Preparation varies by scan type. For a DVT assessment, no preparation is required — wear loose clothing that allows access to the leg from the groin to the ankle. For a carotid Doppler, wear a low-cut top or open collar to allow access to the neck. For a peripheral arterial assessment, wear shorts or trousers that roll up above the knee.
No fasting is required for any vascular ultrasound-scan. If you are taking anticoagulant medication — warfarin, rivaroxaban, apixaban, or heparin — please inform us at the time of booking. This does not affect the scan but is clinically relevant for the interpretation of results.
For urgent DVT assessment, contact us immediately. Do not wait for a GP referral if you have a swollen, painful, or red leg — particularly after a long journey, surgery, or a period of immobility.
Private Vascular Ultrasound-Scan vs NHS Pathway
The table below compares the private pathway at Victoria Medical with the standard NHS route for vascular imaging.
| Factor | NHS Pathway | Victoria Medical (Private) |
|---|---|---|
| Referral | GP referral required (except A&E for suspected DVT) | Self-refer — no GP needed |
| Waiting time (DVT) | Same-day via A&E or urgent GP referral | Same-day — contact us immediately |
| Waiting time (elective) | Typically 6–18 weeks | Same-day or next-day appointment |
| Report turnaround | Days to weeks | Within 24 hours |
| Follow-up | Referred back to GP or vascular surgery | Same-day GP or cardiology consultation available |
| Cost | Free at point of use | From £195 — see Pricing page |
The Clinical Evidence Base
Vascular duplex ultrasound is one of the most extensively validated diagnostic tools in medicine. The following peer-reviewed studies underpin our clinical approach.
Bhatt et al. (2020, Blood Advances) — systematic review of 43 studies — reported pooled sensitivity of 90.1% and specificity of 98.5% for proximal compression ultrasonography for DVT. Whole-leg CUS achieved pooled sensitivity of 94.0% and specificity of 97.3%. The review confirmed that serial CUS has a failure rate of 1.9% — meaning a negative serial scan safely excludes clinically significant DVT in the vast majority of patients.
Hercz et al. (2024, Western Journal of Emergency Medicine) — systematic review and meta-analysis of 15 publications (n = 2,511) — reported pooled sensitivity of 90% and specificity of 95% for emergency physician-performed DVT ultrasound. Three-point compression ultrasound was more sensitive than two-point CUS when performed by specialist physicians.
Varrias et al. (2021, Journal of Clinical Medicine) reviewed the evidence for point-of-care compression ultrasound for DVT and confirmed excellent diagnostic accuracy for acute proximal DVT when performed by trained clinicians, with the additional advantages of immediacy, reduced patient anxiety, and cost-effectiveness compared with formal radiology department scanning.
Kraaijpoel et al. (2020, PLoS ONE) — systematic review of 40 studies (n = 21,250) — compared three CUS strategies and found comparable failure rates of 1.0–1.9% across single limited, serial limited, and whole-leg CUS. The study concluded that strategy selection should be guided by pre-test probability and clinical context.
Kordzadeh et al. (2022, Vascular) evaluated AI-assisted duplex ultrasound for carotid artery disease in 156 patients and reported overall sensitivity of 91%, specificity of 86%, and accuracy of 92% for any carotid artery stenosis — confirming duplex ultrasound as a reliable first-line tool for carotid disease detection.
What to Expect at Your Appointment
Book Your Vascular Ultrasound-Scan
Book online or call 020 3146 9508. For urgent DVT assessment, call immediately — do not wait. No GP referral needed.
Arrive at Victoria Medical
We are at 170 Vauxhall Bridge Road, SW1V 1DX — two minutes from Victoria Station. Wear loose clothing that allows access to the area being scanned.
B-Mode Structural Assessment
Your sonographer performs a greyscale assessment of the vessel walls, identifying plaque, thrombus, or structural abnormalities.
Colour Doppler Flow Assessment
Colour Doppler maps blood flow direction and velocity. For DVT, compression is applied to assess vein compressibility — the primary diagnostic criterion.
Preliminary Findings
Your sonographer discusses what they have observed. A DVT diagnosis is communicated immediately so that anticoagulation can be started without delay.
Written Report and Follow-Up
A detailed written report reviewed by Dr Xynopoulos is available within 24 hours. A GP or cardiology consultation can be arranged to discuss findings and agree a management plan.
Frequently Asked Questions
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