Flat-Detector Computed Tomography for Evaluation of Intracerebral Vasculature for Planning of Stereoelectroencephalography Electrode Implantation.

Abstract

Stereoelectroencephalography (sEEG) requires extensive preoperative planning to optimize placement of electrodes and limit the potential for complications. Flat-detector computed tomography (FD-CT) has previously been used for perioperative vascular imaging to guide the treatment of vascular lesions. This imaging modality provides a detailed depiction of cerebrovascular and bony cranial anatomy, which can be used to guide intracranial electrode implantation. We have developed a novel method to improve preoperative planning for sEEG electrode implantation and limit the potential for postoperative complications by using FD-CT imaging merged with preoperative magnetic resonance imaging (MRI). All patients underwent preoperative FD-CT with selective intra-arterial iodinated contrast dye injection through the late arterial and capillary phases for evaluation of cerebrovascular anatomy. These results were merged with thin-cut MRI for trajectory planning of intracranial sEEG electrodes. All patients underwent routine CT and MRI after electrode placement. 39 patients have undergone sEEG implantation according to this protocol, with a total of 541 electrodes placed. Additionally, 25 (64.1%) patients underwent implantation of 70 oblique insular electrodes. There were no clinically significant complications after the implantations. Thirty-six (92.3%) patients underwent operative intervention, including surgical resection in 27 (69.2%) patients. FD-CT imaging allows for a detailed depiction of cortical cerebrovascular anatomy through the capillary phase, in addition to bony cranial anatomy. This enables the safe planning of complex trajectories, including high-obliquity insular electrodes and transsulcal trajectories through "empty sulci" while also providing concurrent imaging of bony anatomy to allow for preoperative planning of drill depth and anchor placement.