ictal SPECT
Pronunciation: ICK-tal SPECT
Nuclear medicine imaging technique performed during seizures to identify brain regions with altered blood flow.
Full Definition
Ictal SPECT (Single Photon Emission Computed Tomography) is a specialized nuclear medicine imaging procedure performed to capture brain blood flow patterns during an actual seizure. The technique involves rapid injection of a radiotracer (typically 99mTc-HMPAO) during a captured seizure, followed by SPECT imaging within hours. The resulting images show increased blood flow in the seizure onset zone and propagation pathways, providing crucial localizing information for epilepsy surgery planning. When compared with interictal SPECT, ictal images can help distinguish true seizure focus from secondary spread patterns.
Usage
Usage note: SPECT always capitalized; timing of tracer injection is critical for accuracy.
In Context
- "Ictal SPECT demonstrated hyperperfusion in the left temporal lobe during the recorded seizure." — Nuclear medicine report
- "The ictal-interictal SPECT difference images confirmed the suspected seizure focus." — Pre-surgical evaluation