Stereoelectroencephalography Electrode Fixation Using a Silicone Electrode Holder

Anchor bolts are established stereoelectroencephalography (SEEG) electrode fixation devices, but they are difficult to apply in thin cranial bones or in those with reduced cranial bone density. In such cases, the electrodes are fixed on the scalp using sutures. However, this carries risks of electrode damage and displacement during fixation, and the fixation capability depends on the surgeon's skill. A silicone electrode holder was developed as an alternative fixation method, enabling SEEG electrode fixation in situations where anchor bolts are difficult to use and it is structurally designed to address the limitations of suture-based fixation. We aimed to evaluate the feasibility of silicone-based fixation by assessing its strength and safety.

We assessed the fixation capability of the silicone electrode holder in a dry laboratory study and evaluated fixation capability in clinical settings by assessing electrode tip displacement during SEEG monitoring in 24 electrodes fixed using a silicone electrode holder. Safety was evaluated in 10 consecutive SEEG cases using silicone electrode holders.

In the dry laboratory study, the silicone electrode holder withstood 230 g of tension independent of the surgeon's skill. In clinical settings, the median electrode tip displacement was 2.06 mm across the 24 electrodes, with no device-related complications in 10 SEEG cases.

The silicone electrode holder can fix SEEG electrodes in patients with thin cranial bones or a reduced cranial bone density, where anchor bolts are difficult to use. With respect to the fixation capability and safety, the silicone holder exhibited a clinically acceptable performance and demonstrated that the fixation capability does not depend on the surgeon's skill. In cases where anchor bolts are difficult to use, a silicone electrode holder is therefore feasible for electrode fixation.