Single Photon Emission Computed Tomography (SPECT)

SPECT is a nuclear medicine procedure that uses a radioactive compound to create images of the cerebral blood flow. The test has specific use in epilepsy because decreased cerebral blood flow in a focal area is a marker of the interictal epileptogenic zone.

There are two ways of doing the SPECT: during a seizure (ictal) and between seizures (interictal). The ictal SPECT provides the opportunity to image cerebral blood flow during a seizure and identify focal areas of hyperperfusion for the purpose of localization. The interictal SPECT scan is more likely to show a region of decreased blood flow in patients with frequent seizures.


  • The test is not painful; however, an IV will be inserted, which may cause some discomfort.
  • You will be injected with the radioactive isotope.
  • Allow an hour and a half for this procedure.