What Is Wada Testing? A Guide to Epilepsy Testing & Care

When you have epilepsy, finding the right treatment relies on identifying where seizures begin. If surgery is being considered as a treatment option, physicians also need to understand how certain brain functions are organized before deciding how to proceed.

Wada testing is a procedure that temporarily puts one side of the brain to sleep while doctors assess language and memory, and is an essential presurgical evaluation for those with epilepsy. Because Wada testing requires specialized neurological and neurovascular care, patients who need Wada testing in Los Angeles should only consider an interventional neurologist to guide the procedure. 

Continue reading to learn more about how Wada testing is done, when it should be done, and where to find the best neurologist for Wada testing in Santa Barbara. 

What Is Wada Testing?

Epilepsy surgery may be recommended when seizures continue despite appropriate medication and testing identifies an area of the brain where seizures begin. Before surgery, however, the care team needs to understand which areas of the brain support functions that are important to everyday life.

The parts of the brain that affect language and memory need particular attention because surgery near these areas can affect how a person communicates, learns, or remembers information. Wada testing can help physicians determine:

• Which side of the brain is primarily responsible for language
• How each side of the brain contributes to memory
• Whether the brain can support important functions if surgery affects one hemisphere
• How much risk a proposed procedure may carry for language or memory
• Whether additional testing or brain mapping may be appropriate before surgery

The test is only one part of a larger epilepsy evaluation. The best interventional neurologists in Santa Barbara also consider EEG findings, brain imaging, neuropsychological testing, seizure history, and other diagnostic information.

Who Should Get a Wada Test?

Wada testing is not always necessary for every person with epilepsy. Neurologists usually recommend Wada testing when you:

• Have epilepsy that has not responded adequately to medication
• Are being evaluated for epilepsy surgery
• Have seizures that appear to arise near areas involved in language or memory
• Have findings that make language or memory dominance difficult to determine
• Need additional information to assess the potential cognitive effects of surgery
• Have noninvasive test results that do not provide enough information for surgical planning

What to Expect During Wada Testing

Wada testing needs to be done in a controlled medical setting with close monitoring because the procedure temporarily reduces activity on one side of the brain while a neurologist and neuropsychology team evaluate specific brain functions. Wada testing includes several steps:

1. Brain Imaging and Preparation

The medical team prepares you for the procedure and reviews any relevant neurological and imaging information beforehand. EEG monitoring may also be used to observe brain activity during testing.

2. Catheter Placement

The physician guides a catheter through an artery toward the internal carotid artery. This allows medication to reach one side of the brain. Because the procedure involves neurovascular access, endovascular specialists, image-guided techniques, and careful monitoring are important parts of the process.

3. Temporary Inactivation of One Side

Medication is delivered through the catheter to temporarily reduce activity in one hemisphere of the brain. This effect lasts for a short period, giving the care team an opportunity to assess how the other side of the brain handles specific functions.

4. Language Testing

While one side of the brain is temporarily inactive, a trained member of the testing team evaluates language function. The patient may be asked to speak, name objects, answer questions, or complete other language tasks. The goal is to determine which side of the brain supports language and how well the opposite side can maintain that function during temporary inactivation.

5. Memory Testing

The team also evaluates memory during the test. The patient may be shown objects, pictures, or other information and asked to remember them. Once the medication wears off, the team evaluates how well the patient remembers the information presented during the test.

6. Testing the Other Hemisphere

The process may then be repeated on the opposite side of the brain. Comparing the results helps the care team understand how language and memory functions are distributed between the two hemispheres.

What Can Wada Testing Find?

The Wada test provides information about brain function that can help the epilepsy team assess surgical risk. Results may help answer questions about:

Physicians evaluate Wada test results alongside seizure history, neurological examination, EEG findings, imaging, and other presurgical testing to get a full picture of what is happening inside the brain before and during seizure activity. 

Where to Find the Interventional Neurologist in Santa Barbara for Wada Testing

The Vascular and Neuroscience Institute offers Wada testing among our many specialized neurological diagnostic services. Our vast network of neurological experts also provides EEG, EMG, nerve conduction studies, transcranial Doppler studies, VSAT monitoring, and other advanced diagnostic services.

Dr. M. Asif Taqi, MD, FAHA, leads our multidisciplinary team of neurologists and neuroendovascular specialists and is a quintuple-board-certified neurologist trained in neurology, vascular neurology, neurocritical care, critical care neurology, and neuroendovascular surgery. 

If your epilepsy care team has recommended Wada testing, schedule an appointment with the best neurologist for Wada testing to get started.