Wada activation test; intracarotid sodium amobarbital procedure (ISAP)

Indications

• used prior to ablative surgery for epilepsy & sometimes resection of brain neoplasm

Clinical significance

• used to establish cerebral language & memory representation of each hemisphere

Procedure

• sodium amobarbital is injected into one of the internal carotid arteries via a catheter from the femoral artery
• the drug is thus injected into one hemisphere at a time
• the effect is to suppress language &/or memory function in that hemisphere in order to evaluate the other hemisphere
• the patient is engaged in a series of language & memory related tests
• memory is evaluated by showing a series of items or pictures to the patient
• within a few minutes when the effect of the medication is dissipated, the ability to recall can be tested

More general terms

• provocative clinical test