Private Carotid Doppler Ultrasound Scan

A carotid Doppler ultrasound scan — also called carotid duplex ultrasound — is a non-invasive, radiation-free diagnostic test using high-frequency sound waves and Doppler technology to image the carotid arteries in the neck. It produces real-time images of arterial wall structure, blood flow velocity, and detects any narrowing (stenosis) or plaque buildup within the arteries.

It is the recommended first-line investigation for stroke risk assessment, TIA (transient ischaemic attack) workup, and carotid artery disease monitoring. The scan is performed bilaterally — both the left and right sides — in a single appointment, and is included in the single £249 fee at London Private Ultrasound.

NICE guideline NG128: Stroke and transient ischaemic attack in over 16s: diagnosis and initial management (2022).

A private carotid Doppler ultrasound scan at London Private Ultrasound costs £249 — all fees inclusive, both sides, no hidden charges. The single fee covers the complete bilateral assessment of both carotid arteries and both vertebral arteries, immediate verbal results, and a full written report within 24 hours.

We accept all major credit and debit cards, cash, and Klarna for flexible payment. A detailed receipt is provided for insurance reimbursement if applicable.

A carotid Doppler scan is recommended for people with:

• A recent TIA (transient ischaemic attack) or minor stroke — NICE recommends carotid imaging within 24 hours of TIA in high-risk patients
• A carotid bruit heard by their doctor during clinical examination
• Multiple cardiovascular risk factors: hypertension, high cholesterol, diabetes, smoking, or atrial fibrillation
• A strong family history of stroke or cardiovascular disease
• Known coronary artery disease or peripheral arterial disease
• Pre-operative assessment before cardiac or major vascular surgery
• Ongoing surveillance of previously identified carotid stenosis

Screening is also appropriate for individuals over 55 with multiple risk factors who wish to understand their current stroke risk and monitor disease progression over time.

A carotid duplex Doppler scan provides detailed information about:

• Atherosclerotic plaque: Location, extent, composition (soft, calcified, or mixed), and surface characteristics (smooth, irregular, or ulcerated)
• Degree of stenosis: Percentage narrowing quantified using validated NASCET criteria from velocity measurements
• Intima-media thickness (IMT): A measure of subclinical atherosclerosis and an established risk marker for future cardiovascular events
• Blood flow velocity: Peak systolic velocity, end-diastolic velocity, and ICA/CCA velocity ratio — all used to classify stenosis severity
• Vertebral artery flow: Direction and velocity to detect vertebral artery stenosis or subclavian steal syndrome
• Carotid dissection: Intimal flap or false lumen indicating arterial wall tear

Yes. Carotid duplex ultrasound is the primary non-invasive tool for detecting carotid artery disease — a major cause of ischaemic stroke. Studies show that carotid artery disease accounts for approximately 20–25% of all ischaemic strokes. The scan can identify:

• Significant stenosis: Narrowing above 50% that increases stroke risk and may require medical or surgical treatment
• Vulnerable plaque: Soft, echolucent (lipid-rich) plaque is associated with higher stroke risk than calcified, stable plaque
• Increased IMT: Associated with increased risk of both stroke and myocardial infarction independently of traditional risk factors

Early detection of carotid stenosis allows timely intervention. Carotid endarterectomy in symptomatic patients with 70–99% stenosis reduces the risk of subsequent stroke by approximately 65% at 5 years.

European Carotid Surgery Trialists’ Collaborative Group. MRC European Carotid Surgery Trial. Lancet 1998;351:1379–87.

Carotid duplex ultrasound performed by an experienced vascular sonographer has high diagnostic accuracy:

• Sensitivity 89–95% for detecting stenosis ≥70% (NASCET)
• Specificity 85–92% for excluding significant stenosis
• For near-occlusion and occlusion, additional imaging (CT angiography or MR angiography) is typically recommended to confirm findings

Accuracy is highly operator-dependent — experience and vascular-specific qualifications are critical. At London Private Ultrasound, all carotid scans are performed by HCPC-registered vascular sonographers with dedicated MSc-level vascular imaging qualifications.

Blakeley DD et al. Carotid artery duplex sonography — diagnostic criteria and flow dynamics. AJR 2003.

No. You do not need a GP referral. You can self-refer and book directly online or by calling 020 7101 3377. Appointments are available 7 days a week at our Central London clinic (27 Welbeck Street, Harley Street medical district) and our St Albans clinic (54–56 Victoria Street). Urgent same-day appointments are available — please call rather than booking online for same-day requests.

If you have had a recent TIA, please call us directly. After a TIA, NICE recommends urgent carotid imaging within 24–48 hours.

No special preparation is required for a carotid Doppler scan. You should:

• Wear comfortable clothing with an open or low neckline to allow easy access to the neck
• Remove any neck jewellery (necklaces, chains) before arrival

No fasting is required. You may eat, drink, and take medications normally. The scan typically takes 30–45 minutes.

A carotid Doppler scan is completely painless and safe. A water-based gel is applied to the sides of the neck, and a handheld probe moves gently over the skin surface. You will be asked to lie comfortably on your back with your head turned slightly to allow access to each side of the neck. The procedure uses sound waves, not radiation, and has no known side effects.

If significant stenosis is identified, your specialist will explain the findings clearly and immediately generate a formal written report and referral letter for you to take to your GP or vascular surgeon.

Clinical management depends on whether the stenosis is symptomatic (associated with TIA or stroke) or asymptomatic:

• Symptomatic stenosis ≥50% (NASCET): Urgent vascular surgery referral. Carotid endarterectomy is strongly beneficial, reducing 5-year stroke risk by approximately 65%
• Asymptomatic stenosis ≥60–70%: Specialist review, medical optimisation (antiplatelet therapy, statins, blood pressure control), and regular surveillance imaging
• Mild–moderate stenosis: Medical management and lifestyle modification. We will advise on appropriate surveillance interval

Choosing private scanning at London Private Ultrasound does not affect your NHS rights. Our report gives your NHS vascular team everything they need to proceed without delay.

NICE guideline NG128 (2022); European Carotid Surgery Trial (ECST); NASCET Collaborators, NEJM 1991.

Intima-media thickness (IMT) is the combined thickness of the inner two layers of the carotid artery wall — the intima and media — measured in millimetres by high-resolution ultrasound. It is an established, non-invasive marker of subclinical atherosclerosis.

Increased IMT is independently associated with increased risk of:

• Ischaemic stroke (relative risk approximately 1.8 per 0.1mm IMT increase)
• Myocardial infarction (heart attack)

IMT measurement allows early identification of arterial disease before symptoms develop and before stenosis is present, supporting preventive intervention in high-risk individuals. It is particularly useful for monitoring disease progression or regression in response to treatment.

Lorenz MW et al. Prediction of clinical cardiovascular events with carotid intima-media thickness. Circulation 2007;115:459–67.

Carotid duplex ultrasound, CTA (CT angiography), and MRA (MR angiography) are complementary investigations:

• Carotid ultrasound advantages: No radiation (unlike CTA), no contrast injection, no contraindications for metal implants (unlike MRA), real-time assessment, IMT measurement, plaque characterisation, immediate results, lower cost, operator-interactive
• CTA advantages: Excellent overview of the full cervical and intracranial circulation, better for calcified plaque assessment, less operator-dependent
• MRA advantages: No radiation, excellent soft tissue contrast, intracranial vessel assessment

For most patients, carotid duplex ultrasound is the appropriate, cost-effective first-line investigation. CTA or MRA is typically reserved for inconclusive ultrasound findings, suspected intracranial extension, or pre-surgical planning for endarterectomy.

Choosing private care at London Private Ultrasound does not affect your NHS rights or entitlements in any way. Our service provides rapid access to expert vascular assessment — typically same day or next day — so you are not waiting weeks or months for a diagnosis.

If your scan identifies findings requiring urgent NHS attention, our specialist generates a formal report the same day so you can proceed directly to your GP or A&E. For patients with recent TIA, we will ensure you leave with a report that supports an emergency neurovascular referral under NHS 2-week TIA clinic pathways.