Neurophysiology Department Wada Test Patient Information

Transcription

1 Neurophysiology Department Wada Test Patient Information Your Consultant would like you to have a WADA test. We hope that the following information will help to answer any questions you may have. What is a WADA test? This test helps the consultant and neurosurgeon to discover which side of your brain controls speech and memory prior to you being considered for epilepsy surgery. What should I do before the test? Please wash your hair and do not use any hair products (gel, hairspray etc). Take your medication as normal unless otherwise directed by your doctor. You will not be allowed breakfast on the morning of the test. You will be admitted to the ward the day before the test (usually on a Wednesday) and meet members of the psychology department who will explain their part of the procedure to you. On the Thursday, you will be escorted by a porter to the EEG department where a short routine EEG will be recorded. EEG stands for electroencephalogram. This is a recording of your brain waves (the electrical activity of the brain). The signals appear as wavy lines on a computer screen. While on the ward it will be necessary for us to obtain your consent before your investigation begins. 1

2 What will happen during the test? The Clinical Physiologist performing the test will explain each aspect of the test to you and will be happy to answer any questions. You will be sat comfortably on a couch during the EEG. The Clinical Physiologist will obtain a clinical history from you before the test. The Clinical Physiologist will measure your head and mark some points with a soft pencil. Small electrodes will be placed on your scalp using a sticky paste and special glue. While the recording takes place you will be asked to open and close your eyes several times. The recording usually takes minutes. This part of the test is not painful. You will then be taken to the X-Ray department where an angiogram will be performed by the anaesthetist. You will be asked to get onto a special bed and you will then be covered in sterile green sheets. (The X-ray nurse may have to shave a small area of your groin). The first part of the test involves a small catheter being put into the artery in your groin and a special dye being injected into the brain. You will be given a local anaesthetic before the catheter is inserted. This dye helps all the blood vessels in the brain to show up on the X-ray. You may have a warm feeling on one side of the face when the injection is given. The Psychologist will then give you a sentence to try to remember during the section of the test following the injection of the Sodium Amytal. (Sodium Amytal is a drug which will temporarily put half of your brain to sleep while the speech and memory on the other side are tested.) You will then be asked to raise your arms in the air and count up to 10. Within a short time of the injection you may be aware of one of your arms becoming weak and dropping down this is a normal reaction to the drug and will not be permanent. 2

3 While you are still under the effects of the drug, you will be asked several questions by the psychologist. Again this is to test your memory and speech. You will then be left to rest quietly for approximately 10 minutes. The Psychologist will then ask you if you can remember the sentence you were given at the start of the test and if you can recall the other questions asked. Following a 45 minute rest the same procedure will be applied to the other side of the brain. How will this test assist my consultant? This test will help to discover which side of your brain controls both speech and memory. This is an important consideration if you are thought to be suitable to have surgery to help control your seizures. Are there any risks? There is a 1-2% chance of a brain haemorrhage during the procedure. This could result in temporary or permanent incapacity, such as a stroke. There is a small chance that you may have a reaction to the Sodium Amytal and develop some shivering and shaking but this does not last for long. Is the procedure painful? There may be some discomfort when the local anaesthetic is first given. How long does the procedure take? The whole procedure will take between 3 and 4 hours. 3

4 What happens after the test? Once the test is completed the Clinical Physiologist will remove all of the electrodes from your head using a special solution to dissolve the glue. You may wish to bring some shampoo with you to wash your hair after the test as it may feel slightly sticky. The catheter will be removed from your groin and pressure applied to that area for 15 minutes. This helps to stop any bleeding. You will then be taken back to the ward on a trolley. You will be asked to remain flat on the bed for 6-7 hours. You should be able to go home the following day. What are the consequences of not having the Wada test? The Consultant will be unable to determine which side of the brain controls your speech and memory. The Consultant will not have as complete a picture as they require to decide whether or not you are suitable to undergo surgery to try to control your seizures. Are there any alternatives ways of getting the same information? No. However, many areas of research are taking place and the development of scanning techniques may mean that in the future different methods may be available. If for any reason you are unable to make this appointment or have any questions please ring as soon as possible. 4

5 Further information about Wada tests can be found from numerous organisations including: 1. UK Epilepsy Society Helpline: or visit 2. Epilepsy Action Helpline (Freephone): or visit 3. An Epilepsy Therapy Project Initiative of the Epilepsy Foundation: This information can be translated on request or if preferred an interpreter can be arranged for additional information regarding these services please contact the Walton centre on and ask for the Medical Records Manager. 5

6 For practical advice our Customer Care Team provide a (PALS) service. Contact Customer Care Team on , customer.careteam@thewaltoncentre.nhs.uk or Alternatively, log on to: or call for advice and information for people with neurological conditions and their carers. Title: WADA test Patient Info Author: Caroline Finnegan/Sue Kirkham/Neurophysiology Department Version No: 3 Date of Approval: August 2013 Date of Review: August 2015 The Walton Centre for NHS Foundation Trust. All rights reserved. No reproduction by or for commercial organisations is allowed without the express written permission of the Walton Centre 6