Cerebral angiogram

Your doctor has requested that you have a cerebral angiogram. We hope the following information will answer some of the questions you may have about this procedure.

What is a cerebral angiogram?

An angiogram is a procedure where blood vessels are examined closely, by means of x-rays. A special dye called contrast medium is injected into an artery through a fine plastic tube called a catheter and then images are taken immediately afterwards. In your case we will be looking specifically at the head and neck vessels.

Why do I need to have a cerebral angiogram?

The purpose of this procedure is to enhance and increase the information that the doctors may already have from MRI, CT or Ultrasound, in order to have a detailed map of your head and neck circulation.

Who has made this decision?

Your suitability for the treatment will have been made 
by the doctor in charge of your case and the consultant neuroradiologist (specially trained X-ray doctor) at the hospital. The purpose of the procedure and potential complications will have been explained and will be explained again when you attend for treatment.

What are the risks associated with cerebral angiograms?

Generally it is a very safe procedure. Potential complications are uncommon and include:

  • A small risk of stroke (1 in a 1,000 permanent deficit).
  • A small risk of damage to the blood vessels in the leg.
  • Bleeding or haematoma (a bruise under the skin) around the puncture site (usually at the top of leg), which should settle down by itself.
  • Very rarely an allergic reaction to the contrast medium.
  • The procedure uses x-rays and the amount of radiation used is small, however if you think you may be pregnant please inform the Imaging department before attending the appointment.

What happens before the procedure?

Prior to the procedure you will have already:

  • Attended Pre Assessment clinic/ completed a telephone consultation – to perform standard checks: for example blood tests, MRSA test and discussion of existing medication.
  • There is no preparation for this procedure; you can continue to eat and drink as normal, unless instructed otherwise.
  • If you are taking any blood thinning tablets which include anti platelets please contact the department before the appointment using the number on your appointment letter, you may need to consult your GP before undergoing this test.
  • Please make arrangements for someone to collect you from the hospital and take you home by car, as we advise not to use public transport. You are not permitted to drive for 24 hours post procedure and we would like someone to stay with you at home in the first 24 hours. Please inform the department if this is not possible, as we will need to identify alternative arrangements. 

On the day of the procedure:

  • You will arrive at the Imaging Department (Gate 19) and be accompanied into our day case area.
  • Please inform us if you are allergic to anything.
  • You may take your normal medication unless instructed otherwise.
  • A radiologist will discuss the procedure with you and the benefits and potential risks to you. You will have an opportunity to ask questions about the procedure. If you choose to have the procedure you will need to sign a consent form.
  • You will be asked to change into a hospital gown.
  • Once all the checks have been performed and consent signed, you will be taken to the angiography suite. You will be asked to lie down on the X-ray table for the procedure and this may take up to one hour. There will be a small team of nurses, doctors and radiographers with you throughout.
  • The nurse will then clean the area at the top of your leg with an antiseptic solution and cover you with sterile drapes. The x-ray machine at this point may move around you, but will not touch you.
  • The doctor will then inject local anaesthetic into the area at the top of your leg, which may briefly sting and then go numb. After this, you may just feel a pushing sensation when a small plastic tube (catheter) is inserted into your femoral artery and the catheter fed through.
  • Once the catheter is manoeuvred into the correct positions, contrast medium is injected into different blood vessels and images are then acquired. The injection of the contrast medium, may give you a momentary warm feeling, a strange taste in your mouth and flashing lights behind the eyes. This will not last, however it is important that you stay still throughout in order to achieve the clearest pictures possible.
  • Once the doctor has acquired enough images, the X-ray machine will be removed and the doctor will then press on the puncture site for ten minutes, or until the bleeding has stopped. The nurses will then put fresh swabs over the site and ask you to press on these whilst transferring you back to your bed and recovery.

What happens after the procedure?

  • You will be taken back to the day case initially, so that nursing staff may monitor you closely.
  • You will be required to stay flat for 1 hour and then sit up for a further two hours. Then walk around for half an hour.
  • If you are going to sneeze, cough or laugh, you must put firm pressure over the puncture site to protect the artery from re-bleeding. If you feel the wound site is re-bleeding, please inform the nurse.
  • You will be able to eat and drink as normal, but please make sure you drink plenty after this procedure, to help eliminate the contrast medium that the doctor has used from the body.
  • You may experience some bruising around the puncture site, but this should fade over a few days.
  • At home, please rest your leg to enable healing of the puncture site in your groin. Avoid activities during the next two to three days which may strain your leg, for example running or lifting.

What happens next? 

  • The Neuroradiologist will need to examine all the images very carefully before writing a report and possibly discuss findings with the doctor in charge of your case. The report will be sent to your GP and a follow up arranged as appropriate.
  • If you experience any symptoms you are concerned about, please contact the radiology department directly or alternatively contact your GP or the emergency department.

Finally, we hope this information is helpful. If you have any questions either before or after the procedure the staff in the X-Ray department will be happy to answer them.

The telephone number for the X-Ray department can be found on the appointment letter.


Information for patients undergoing an angiogram. RCR 2008 www.RCR.ac.uk

Kaufmann et al. Complications of Diagnostic Cerebral Angiography: Evaluation fo 19 826 Consecutive Patients.Radiology: Vol 243: Number 3- June 2007

Public Health England “Guidance - Exposure to ionising radiation from medical imaging: safety advice” (2014)

NHS Constitution - Information on your rights and responsibilities. www.nhs.uk/aboutnhs/constitution

How to contact us:

Southmead Hospital,


BS10 5NB.

See your appointment letter for the number to phone with any queries you may have.


If you or the individual you are caring for need support reading this leaflet please ask a member of staff for advice.

© North Bristol NHS Trust. This edition published February 2020. Review due February 2022. NBT002790

Cerebral angiogram