Oblique trajectory angles in robotic stereo-electroencephalography.

Area of Science:

• Neurosurgery
• Epileptology
• Medical Imaging

Background:

• Traditional stereo-electroencephalography (sEEG) relies on orthogonal trajectories, potentially limiting access to seizure network components.
• Advances in robotic stereotaxy and neuronavigation enable oblique trajectories, but their safety and efficacy remain under investigation.

Purpose of the Study:

• To evaluate the accuracy and efficacy of oblique versus orthogonal trajectories in robotic sEEG electrode implantation for seizure network sampling.

Main Methods:

• Retrospective analysis of 150 procedures (2040 electrodes) in 134 patients.
• Categorization of electrodes into oblique (>30° entry angle) and orthogonal trajectories.
• Accuracy assessment by comparing postimplantation imaging deviations from planned trajectories.

Main Results:

• Mean deviations were comparable: 1.57 mm (entry) and 1.89 mm (target) for oblique vs. 1.38 mm and 1.69 mm for orthogonal.
• Entry angle showed negligible impact on deviation; target deviation was not significantly affected by entry angle.
• No hemorrhagic or infectious complications were observed; 84% of patients achieved Engel class I or II outcomes.

Conclusions:

• Oblique trajectories demonstrate comparable accuracy and excellent safety and efficacy to orthogonal trajectories in robotic sEEG.
• Patient outcomes suggest successful seizure focus localization with oblique trajectories.
• Findings support the routine use of oblique trajectories for investigating seizure networks.