Ictal 99mTc HM-PAO brain single-photon emission computed tomography in electroencephalographic nonlocalizable...

A 9-year-old child with intractable focal epilepsy was studied for possible surgical treatment. Multiple electroencephalographic studies did not localize the epileptic focus. An ictal single-photon emission computed tomography (SPECT) study with technetium 99m-hexamethylpropyleneamineoxime demonstrated a focal area of hyperperfusion. Through three-dimensional, functional to anatomical image-matching techniques, the focus was overlaid on the magnetic resonance image localizing the cortical convolution responsible for the epileptogenic focus. Subdural electroencephalographic studies performed for seizure localization and functional mapping confirmed this location. This case emphasized the usefulness of ictal SPECT scans in patients with seizures nonlocalizable by electroencephalography being evaluated for epilepsy surgery.