Automatic trajectory planner for StereoElectroEncephaloGraphy procedures: a retrospective study.

In StereoElectroEncephaloGraphy (SEEG) procedures, intracerebral electrodes are implanted in order to identify the epileptogenic zone in drug-resistant epileptic patients. This paper presents an automatic multitrajectory planner that computes the best trajectory in terms of distance from vessels and guiding screws angle, once the candidate entry and target regions are quickly and roughly defined. The planning process is designed also to spare some brain structures, such as cella media and trigone of the lateral ventricles and brain stem. The planner was retrospectively evaluated on 15 patients who had previously undergone SEEG investigation. Quantitative comparison was performed computing for each patient and for each electrode trajectory 1) the Euclidean distance from the closest vessel; 2) the trajectory incidence angle (guiding screws angle); and 3) the sulcality value. The automatic planner proved to satisfy the clinical requirements, planning safe trajectories in a clinical-compatible timeframe. Qualitative evaluation performed by three neurosurgeons showed that the automatically computed trajectories would have been accepted by them.