Bilateral Deep Brain Stimulation: The Placement of the Second Electrode Is Not Necessarily Less Accurate Than That of the First One

Abstract

Background: Deep brain stimulation (DBS) is recognized as an effective treatment for movement disorders. We recently changed our technique, limiting the number of brain penetrations to three per side. Objectives: The first aim was to evaluate the electrode precision on both sides of surgery since we implemented this surgical technique. The second aim was to analyse whether or not the electrode placement was improved with microrecording and macrostimulation. Methods: We retrospectively reviewed operation protocols and MRIs of 30 patients who underwent bilateral DBS. For microrecording and macrostimulation, we used three parallel channels of the ‘Ben Gun' centred on the MRI-planned target. Pre- and post-operative MRIs were merged. The distance between the planned target and the centre of the implanted electrode artefact was measured. Results: There was no significant difference in targeting precision on both sides of surgery. There was more intra-operative adjustment of the second electrode positioning based on microrecording and macrostimulation, which allowed to significantly approach the MRI-planned target on the medial-lateral axis. Conclusion: There was more electrode adjustment needed on the second side, possibly in relation with brain shift. We thus suggest performing a single central track with electrophysiological and clinical assessment, with multidirectional exploration on demand for suboptimal clinical responses.

A Comparison of Unilateral Deep Brain Stimulation (DBS), Simultaneous Bilateral DBS, and Staged Bilateral DBS Lead Accuracies

“…We find that second leads placed via a staged procedure result in the same accuracy as those placed during simultaneous bilateral procedures and that bilateral DBS is comparable in accuracy to unilateral DBS. Further, we demonstrate the number of MER was higher on the first side in our simultaneous bilateral cohort in contrast to recent findings by Sadeghi et al . Additionally, target and age had no overall impact on accuracy.…”

“…Finally, in contrast to Sadeghi et al who attributed similar accuracies for simultaneous bilateral leads to additional intraoperative adjustments made to the second, we performed a greater number of MER on the first side. Of note in our practice, despite what we find on the first side, we do not alter our plan for MER on the second side unless there is a finding which precludes us from attempting the second side.…”

Learning curve in anatomo-electrophysiological correlations in subthalamic nucleus stimulation

“…This was only partially confirmed by Bour et al, who described a non-significant trend towards a less When comparing the correlation between anatomical and final targets between the first and second side operated on, the correlation was better on the first operated side in Group 1 according to the percentage of anatomical electrodes. The role of increased brain shift for this worsening discrepancy was not confirmed by our results, but a paper by Sadeghi et al indicated a decreasing quality of intraoperative monitoring on the second side operated on caused by fading cooperation with the patient during lengthy surgery as a potentially responsible factor causing anatomo-clinical differences (23). However, decreasing percentage of anatomical trajectories on the second side operated on was not confirmed in our Group 2.…”

“…In Group 1, the position of the final electrodes (related to MicroDrive ports) was symmetrical in only 13 patients (26%) and both electrodes were implanted along central -anatomical (23). In a paper published by Amirnovin et al, the frequencies of central-anatomical electrode trajectories were 39% on the first side implanted (left) and 42% on the second side implanted (right)(2).…”

Sequence of electrode implantation and outcome of deep brain stimulation for Parkinson's disease

“…The authors reported that a deviation of >1 mm in the location of anterior commissure was detected in up to 8% of their patients. In a small study, Sadeghi et al 16 also assessed the distance between planned and expected target in bilateral STN DBS procedures. Although more adjustments in trajectory were needed on the second implanted side, the deviations in X and Y axes failed to reach statistical significance.…”