Effective accuracy of stereoelectroencephalography: robotic 3D versus Talairach orthogonal approaches

Stereoelectroencephalography (SEEG) was first developed in the 1950s by Jean Talairach using 2D angiography and a frame-based, orthogonal approach through a metallic grid. Since then, various other frame-based and frameless techniques have been described. In this study the authors sought to compare the traditional orthogonal Talairach 2D angiographic approach with a frame-based 3D robotic procedure that included 3D angiographic interoperative imaging guidance. MRI was used for both procedures during surgery, but MRI preplanning was done only in the robotic 3D technique.

All study patients suffered from drug-resistant focal epilepsy and were treated at the same center by the same neurosurgical team. Fifty patients who underwent the 3D robotic procedure were compared to the same number of historical controls who had previously been successfully treated with the Talairach orthogonal procedure. The effectiveness and absolute accuracy, as well as safety, of the two procedures were compared. Moreover, in the 3D robotic group, the reliability of the preoperative MRI to avoid vascular structures was evaluated by studying the rate of trajectory modification following the coregistration of the intraoperative 3D angiographic data onto the preoperative MRI-based trajectory plans.

Effective accuracy (96.5% vs 13.7%) and absolute accuracy (1.15 mm vs 4.00 mm) were significantly higher in the 3D robotic group than in the Talairach orthogonal group. Both procedures showed excellent safety results (no major complications). The rate of electrode modification after 3D angiography was 43.8%, and it was highest for frontal and insular locations.

The frame-based, 3D angiographic, robotic procedure described here provided better accuracy for SEEG implantations than the traditional Talairach approach. This study also highlights the potential safety advantage of trajectory planning using intraoperative frame-based 3D angiography over preoperative MRI alone.