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Vein map ultrasound scan to plan for a bypass operation

Patient information A-Z

What is a bypass and what is a vein map?

A bypass graft is often performed to treat blockages in the arteries in your legs. It may also be performed if you have an aneurysm. This is when the walls of the artery get weak and expand.

A bypass is where a vein taken from another area in your leg is used to re-route the blood flow around the blockage or weakened artery walls. If your consultant is considering doing a bypass graft in your leg, they may ask us to do a vein map.

This test uses ultrasound to produce images of the superficial veins (veins near the surface) of the legs. It is a safe and effective way to assess whether there is a vein suitable for bypass. This involves ensuring that there are no blockages in the vein and that the vein is a suitable size.

The results of this test will allow the consultant to appropriately plan your treatment.

The test is painless and does not use any radiation or needles. There are no risks associated with this test.

About the test

Where do I go?

The vascular studies unit (VSU) is on Level 5 of the Addenbrooke’s treatment centre (ATC). Please inform reception of your arrival straight away. There are often other clinics in progress, so you may not be called in order of arrival. You may bring a relative or friend in with you during the test or request a chaperone if you would like one.

What is consent?

Before your test is performed you must give your consent or permission. Consent is the process by which you give permission to healthcare professionals to provide your care and treatment. It may be implied (offering your arm for a blood pressure reading) or formal (signing a formal consent form for an operation). In either case your consent must be given voluntarily, and you must have all the information you need to make a decision. If you feel you do not have enough information or do not understand the procedure, please ask.

How is a vein map ultrasound scan performed?

There is no preparation needed and you may eat and drink as usual prior to the test.

A clinical vascular scientist will perform and interpret your ultrasound scan. You will be asked to remove your shoes, socks/ tights and trousers or skirt. The lights will be dimmed to allow the best images to be obtained.

If possible, the scan will be performed with you lying down on the couch. Gel is applied to your leg and the scan is carried out from the groin down to the ankle. The ultrasound probe will be moved down the leg to view the superficial veins. The scan takes approximately 30 to 60 minutes.

A patient lies on their back on a scanning couch. A clinical vascular scientist uses a probe to scan the leg veins.

What happens next?

The clinical vascular scientist can comment briefly on the findings and will write a report for the consultant who requested the test. You will be able to discuss the results of this investigation fully with the referring team at your next outpatient appointment.

In rare cases, the clinical vascular scientist may need to discuss the result with a doctor before you leave.

Contacts / further information

If you require further information, please do not hesitate to call the vascular studies unit (VSU) on 01223 348117.

Privacy and dignity

Same sex bays and bathrooms are offered in all wards except critical care and theatre recovery areas where the use of high-tech equipment and/or specialist one-to-one care is required.

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

Help accessing this information in other formats is available. To find out more about the services we provide, please visit our patient information help page (see link below) or telephone 01223 256998.

Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151