The Usefulness of Intraoperative Cerebral C-Arm CT Angiogram for Implantation of Intracranial Depth Electrodes in Stereotactic Electroencephalography Procedure.

Background: Stereotactic electroencephalography (SEEG) is an invasive diagnostic tool for localizing the epileptic zone in patients with medically refractory focal epilepsy. Despite technical and imaging advances in guiding the electrode placement, vascular injury is still one of its most serious complications.

Object: To investigate the usefulness of intraoperative cerebral C-arm CT angiogram (CCTA) in avoiding intracranial hemorrhagic complications during SEEG electrode implantation.

Methods: Trajectory data from 12 patients who underwent SEEG electrode implantation were studied in detail. This included an analysis of the implantation of 146 SEEG electrodes, which were guided by intraoperative CCTA, as well as the standard planning based on preoperative contrast-enhanced MRI. In addition, a prospective analysis of SEEG hemorrhagic complications using the studied methodology was performed in a total of 87 patients receiving 1,310 electrodes.

Results: There was no complication related to the CCTA itself. Intraoperative CCTA entailed modification of the original trajectory based on the preoperative MRI in 27 of 146 electrode implantations (18.5%). In 10 of them, a severe vascular complication was adverted by intraoperative CCTA. The safety of this new approach was also confirmed by the analysis of postinterventional CT, which revealed a symptomatic hematoma caused by 1 single electrode out of the 1,310 implanted.

Conclusions: This study showed that intraoperative CCTA in addition to preoperative MRI is useful in guiding a safer SEEG electrode implantation. The combination of both imaging modalities essentially minimizes the risk of serious hemorrhagic complications.