Systematic Stereotactic Error Reduction Using a Calibration Technique in Single-Brain-Pass and Multitrack Deep Brain Stimulations.

Background: A calibration technique that shifts the frame coordinates from the intended coordinates to correct a systematic stereotactic error has been reported for single-brain-pass deep brain stimulation.

Objective: To analyze the intercenter reproducibility of this method for deep brain stimulation.

Methods: A total of 310 leads from 166 patients undergoing surgery were analyzed, including 220 multitrack (primarily 3-track) subthalamic nucleus leads, 17 single-brain-pass subthalamic nucleus leads, and 73 single-brain-pass globus pallidus interna leads. We adopted the previously reported calibration factors. Calibration shifts the frame coordinates from the target coordinates to the left, anterior, and inferior directions by 0, 0.5, or 1 mm, respectively, according to the arc angles in each axis. We analyzed 9 subgroups of single-brain-pass, multitracks, operated sides, technical, and instrumental variations.

Results: In total, the stereotactic error decreased from 1.5 ± 0.8 mm in the distance to the frame coordinates (error calculation before using the calibration technique) to 1.1 ± 0.6 mm in the distance to the intended target coordinates (error after using the calibration technique, 28% reduction, P < .000001). Frame-related errors were 0.1 to 0.3 mm when measured with the stereotactic simulator. The reduction of stereotactic errors by the calibration technique (median 0.4 mm, 0.1-0.7 mm, median 28%, 7%-45% in each subgroup) was significant in 8 of the 9 subgroups (P < .05).

Conclusion: Calibration is an effective and reproducible method for reducing systematic stereotactic errors both in single-brain-pass and multitrack deep brain stimulations, as well as in both sides using various instrumental and technical conditions.