WADA test is a diagnostic test which is used in epileptic patients to check which side of the brain is affected by epilepsy. The term ‘WADA’ does not stand for any abbreviation instead stands for the name of the Japanese physician, ‘Juan Wada’ who first performed it. WADA test is also referred to as the Amytal study / ISAP (Intracarotid sodium amobarbital procedure) as sodium amobarbital is used during the test to put the side of the brain to sleep. This is test which is basically performed to check the language and the memory functioning of the brain.
When is WADA test advised ?
WADA test is advised in individuals who are affected with epilepsy, to identify which part of your brain is affected and which part performs better functions of memory and speech. The test is usually advised by your treating neurologist depending upon your signs and symptoms or if you could be posted for a surgery soon.
This test can be performed in both children and adults who are affected by epilepsy.
Who performs the WADA test ?
WADA test is performed by your neurologist and a neuroradiologist or a neurologist who specializes in epilepsy.
How do you prepare for a WADA test ?
Before you are posted for a WADA test you will be asked to undergo a cerebral angiogram to declare you fit for the procedure. The cerebral angiogram is performed to check the blood supply to the brain. You will be reviewed for overall health, previous history of any diseases, medications and your medication will be reviewed before the procedure.During the cerebral angiogram, a catheter will be inserted into the internal carotid artery of the neck which is later used for the WADA test.
What happens during a WADA test ?
The main principle of the WADA test is to check the activity of the brain, so during the test one half of the brain (one side) is put to sleep where the other is examined for its functioning. The one-half side of the brain is put to sleep by injecting anesthetic medication (sodium amobarbital) in the internal carotid artery of the respective side. For instance, if the anesthetic solution is injected in the right carotid artery, the right side of the brain is put to sleep till the effect of anesthesia wears off. Electroencephalogram (EEG) is also performed to check the activity of brain during the test.
Once the consultant is sure that one part of your brain is asleep, the doctor will check for your speech, language, and memory by asking questions and showing you pictures and words and your responses will be recorded. Once the effect of anesthesia wears off you and the other side of your brain is also active, you will be asked the same questions and same pictures and words are shown again, to check if you remember that those were shown earlier. The test responses are recorded.
The same test is then repeated for the other side of the brain and the readings are recorded. The test takes about an hour or more to complete and the test results are discussed by the doctors after the test with you.
You might be asked in to stay in the hospital for a few hours to one day to check the site of catheter insertion and for your overall health monitoring.
What do the results of WADA tests imply ?
The recordings of WADA test help in interpreting which part of your brain has better memory function, which has better language and speech function and which part is affected by epileptic seizures.
What are the risks and complications associated with WADA test ?
WADA test is a diagnostic test and hence the complications are fewer. But, since this is an interventional procedure it carries the risk of stroke in some patients.
Disclaimer: The content provided here is meant for general informational purposes only and hence SHOULD NOT be relied upon as a substitute for sound professional medical advice, care or evaluation by a qualified doctor/physician or other relevantly qualified healthcare provider.
