Accuracy of Electrode Insertion Using Frame-Based With Robot Guidance Technique in Stereotactic Electroencephalography: Supine Versus Lateral Position

Abstract

Placing the patient in lateral position is an option for implantation of stereoelectroencephalography (SEEG) electrodes that have a posterior entry point. Previous studies reported the accuracy of SEEG electrodes but not specifically in relation to position. The aim of this study was to analyze accuracy of SEEG electrodes by position. Entry point and target accuracy of electrodes implanted in lateral position were compared with electrodes implanted in supine position using a frame-based with robot guidance technique. Subgroup analysis was performed for insular versus noninsular electrodes. Analysis included 23 consecutive patients (11in lateral position) with 294 electrodes. The entry point error was similar between lateral (median 1.3 mm [interquartile range 0.8-1.9]) and supine (1.2 mm [0.8-1.7]; P=0.360) position. Target accuracy was better in lateral (1.8 mm [1.3-2.7]) than supine (2.9 mm [2.0-4.4]; P < 0.001) position. For noninsular electrodes, the median entry point error in lateral and supine position was 1.3 mm (0.8-1.9) and 1.2 mm (0.8-1.7; P= 0.43), respectively. The accuracy was better in lateral position (median 1.7 mm [1.2-2.6]) compared with supine position (2.9 mm [2.0-4.4]; P < 0.001). The accuracy of insular electrodes was similar in both positions for entry point (lateral: median radial error 1.4 mm, [0.7-1.9]; supine: 1.1 mm [0.6-1.8]; P= 0.833) and target (lateral: median three-dimensional error 2.3 mm [1.6-3.2]; supine: 2.9 mm [2.4-4.5]; P= 0.07). SEEG leads implanted in lateral position exhibit an accuracy and safety profile in accordance with previous studies. In this cohort, target error was smaller in the lateral position, particularly in noninsular electrodes.