What is the Wada test?
The intracarotid amobarbital test or Wada test is part of the pre-surgical evaluation in patients considered for epilepsy surgery. A thin plastic tube is inserted under local anesthesia into an artery at the groin and threaded into the carotid artery in the neck. A short-acting anesthetic agent is injected into the carotid artery. Each half of the brain is put to sleep for a few minutes. During that time, the patient’s ability to speak, understand speech and memory is evaluated. After the medication wears off, the process is repeated with the other hemisphere. The Wada test determines which cerebral hemisphere is “dominant” for speech, and if memory is functional on one or both sides of the brain. The test takes a few hours and patients usually go home the same day.
