Ictal near-infrared spectroscopy and electrocorticography study of supplementary motor area seizures

Abstract

The seizure onset zone (SOZ) and propagation pathways in supplementary motor area (SMA) seizures are difficult to identify because of the short duration and swift propagations of this seizure type. Herein, we studied ictal cerebral blood flow changes, seizure electrical activities, and clinical signs employing simultaneous near-infrared spectroscopy (NIRS) and electrocorticography (ECoG) recordings in a brain tumor patient with SMA seizures. Increased cerebral blood flow was observed from the SOZ in the ipsilateral SMA and spread to the ipsilateral premotor cortex, ipsilateral sensorimotor cortex, and also the contralateral hemisphere. These propagation patterns were concordant with ictal ECoG seizure activities and clinical signs. Removal of the SOZ and surrounding areas, where the higher blood flow and higher frequency oscillations had been identified, achieved a good outcome for this patient. Our ictal NIRS-ECoG technique is robust and useful for detecting the SOZ and seizure propagations.