A venous reflux ultrasound maps the leg veins and assesses the direction of blood flow. It can help investigate varicose veins and chronic venous symptoms, and it supports an appropriate treatment or specialist pathway. New one-sided swelling, pain or warmth needs urgent assessment for possible DVT rather than a routine reflux scan.
Duplex ultrasound is used to evaluate superficial venous reflux and guide the management of varicose veins. Recent vascular guidelines use duplex assessment as an important part of the clinical evaluation, with treatment decisions based on symptoms, anatomy and the patient’s wider circumstances.[1]
I distinguish chronic vein symptoms from acute symptoms that need urgent care. This page explains the planned mapping pathway and when you should not wait for a routine appointment.
Written & reviewed by
Dr George Xynopoulos
Consultant Physician and Cardiologist, GMC registered
What I Assess With a Venous Reflux Ultrasound Scan
The scan maps relevant superficial and deep veins and assesses blood-flow direction with Doppler imaging. It can identify reflux-related patterns in the vein segments examined, but it does not replace urgent DVT assessment when symptoms are new or rapidly changing.
| Part of the assessment | What the scan can help show |
|---|---|
| Superficial veins | Relevant vein anatomy and reflux-related flow |
| Deep veins | Flow and patency features relevant to the examination |
| Varicose tributaries | Visible surface-vein distribution that may inform the care pathway |
Preparation Before Your Appointment
No fasting or bladder preparation is needed. Wear loose trousers, shorts or a skirt. You may be asked to stand for part of the scan so that the sonographer can obtain the views needed for vein mapping.
Preparation summary: No special preparation. You may be scanned standing; wear loose clothing, shorts or a skirt.
What Happens During the Scan
The sonographer uses Doppler imaging while you are lying down and, where appropriate, standing. Gentle compression or movement manoeuvres may be used to assess the pattern of blood flow.
- Bring any relevant referral letter, previous scan report or clinic letter if you have one.
- Tell the team about new symptoms, recent surgery, hospital admissions and medicines that affect blood clotting.
- Ask if you are unsure whether this is the right examination before the scan begins.
How I Use the Result in Your Care Pathway
I use the mapping report with your symptoms, skin changes, medical history and treatment aims. I can then advise whether conservative care, a specialist-vein consultation or another pathway is appropriate.
When to Seek Urgent Medical Help
Seek urgent assessment for new one-sided leg swelling, pain or warmth; a painful red hard vein with fever or feeling unwell; chest pain; shortness of breath; coughing blood; or rapid deterioration.
A routine ultrasound booking is not emergency care. If symptoms are sudden, severe, worsening, or include chest pain, breathing difficulty, collapse, new neurological symptoms or a cold painful limb, call 999 or attend A&E.
What to Expect at Your Appointment
Check the clinical question
Before your appointment, I want the team to understand your symptoms, relevant history and the part of the circulation that needs assessment.
Follow the preparation advice
You may be scanned standing; wear loose clothing, shorts or a skirt.
Have your duplex ultrasound
A sonographer uses an external probe, greyscale imaging and Doppler assessment of blood flow where relevant.
Plan the next step
Your report is considered alongside your symptoms and clinical history so that I can advise on suitable follow-up or urgent care.
Frequently Asked Questions
References
- [1]Gloviczki P, et al. 2023 clinical practice guidelines for management of varicose veins of the lower extremities. Journal of Vascular Surgery: Venous and Lymphatic Disorders. DOI: 10.1016/j.jvsv.2023.08.011.
- [2]NICE. Varicose veins: diagnosis and management (CG168).
- [3]European Society for Vascular Surgery. 2022 clinical practice guidelines on chronic venous disease.
Related Services at Victoria Medical