This page is for parents and carers of children with sickle cell disease. It explains what happens during a Transcranial Doppler Scan.
As part of your child’s care in the Sickle Cell Clinic we offer TCD as a regular screening test starting at the age of two. TCD helps to identify children who are at an increased risk of having a stroke. By using screening tests, such as blood tests and TCD, we aim to detect and treat any problems at an early stage.
A Doppler machine uses an ultrasound probe (similar to the ultrasound test used during pregnancy) to see how fast blood is flowing in the vessels in the brain. This allows the speed of blood flow to be measured in some of the arteries (blood vessels) supplying the brain. If arteries are narrow, the blood travels faster through them and the probe makes a higher pitched noise.
In most children with sickle cell disease, the TCD is normal. If the scan is abnormal we may need to repeat it or do further tests to check the arteries. If it is borderline (known as ‘conditional’), we will perform a repeat test within the next few weeks.
We recommended that all children have this screening test when they are two and then yearly after that. This can be less frequent in children with HbSC disease.
The TCD test helps to detect problems related to blood flow to the brain at an early stage. We can then talk to you about more detailed tests and treatment options to help prevent serious problems, such as having a stroke. For example, some large studies in America showed that the risk of stroke was dramatically reduced in children with high blood flow who had regular blood transfusions.
TCD is safe and there are no risks associated with it.
The scans are only performed once a month so if your child is unable to make the appointment, please contact us as soon as possible.
The test will be performed in the Children’s Outpatient Department, Elizabeth Garrett Anderson Wing, University College Hospital. You will see your child’s consultant and CNS but the scan will be performed by a doctor from another hospital. This is to allow your child’s consultant sufficient time for the consultation.
The scan usually takes about 30 minutes but it may take longer with younger children. It is painless and your child needs to be relaxed and still during the scan. They will be awake and lying on a couch and you will be able to stay with them.
The results will be analysed by Dr Trompeter, consultant paediatric haematologist. This usually happens on the same day. If the results are normal, we will plan to repeat the test every year or so. If the results show fast blood flow, indicating possible blood vessel narrowing, or don’t give clear results, we will arrange another TCD test within a few weeks. A summary of the result will be in your clinic letter.
We may also arrange other tests, including:
- MRI and MR A (magnetic resonance imaging and angiography) – a painless scan to check the brain and its blood vessels in more detail
- imaging TCD (TCDi) – another painless scan to identify the blood vessels when we are having difficulty using the traditional non-imaging TCD.
If the scan(s) show narrowing of blood vessels, this may indicate a reduced blood flow to part of the brain and an increased risk of having a stroke in the future. If this is the case, we will explain what the results mean and tell you about the available treatment options to reduce this risk.
Haematology admin team: uclh.
Haematology clinical nurse specialists (CNSs): uclh.
Haematology advice line (office hours, children and adults): 020 3447 7359
Adult haematology advice line (out of hours): 07852 220 900
Paediatric helpline (out of hours):
- nurse in charge 07961 081 645
- ward T11S 020 3456 7890 ext. 71103 or 71143
Apheresis: 020 3447 1803
Address: The Joint Red Cell Unit, Department of Haematology, 3rd Floor West, 250 Euston Road, London NW1 2PG
Website: www.
Consultants:
- Dr Emma Drasar
- Dr Perla Eleftheriou
- Dr Andrea Leigh
- Dr Ryan Mullally
- Professor John Porter
- Dr Sara Trompeter
Specialist nurses:
- Christopher Dean
- Enitan Roberts
- Alexandra Saville
Matron:
- Bernadette Hylton
Services
Page last updated: 24 July 2024
Review due: 30 September 2024