Introduction: Deep brain stimulation (DBS) lead placement using intraoperative MRI (iMRI) is an alternative surgical technique utilizing real-time intraoperative neuroimaging to guide electrode placement. However, there is limited literature on clinical outcomes with this procedure, especially in comparison with more traditional DBS guided by microelectrode recordings (MER).

Methods: All patients with PD undergoing GPi-DBS between July 2007 and August 2016 with either MER-guidance or iMRI-based targeting using ClearPoint® (MRI Interventions) were retrospectively identified. Measures including lead location and lead placement accuracy, adverse events, pre-operative and 12 month post-operative follow-up DBS UPDRS-III motor scores, levodopa equivalent daily dose, and stimulation parameters were obtained and stratified by surgical procedure.

Results: Seventy-seven patients underwent GPI lead placement with a total of 131 DBS leads. The stereotactic accuracy of the ClearPoint system with respect to lead placement was 1.07 ±0.10 mm, while complication rates were 17.2% vs. 20.8% for MER- and iMRI-guided DBS, respectively. Sixty three patients were included in clinical outcome analyses based on predefined inclusion criteria – 20 underwent MER-, and 43 underwent iMRI-guided DBS. The overall improvement in UPDRS-III motor scores was 36.2 ±3.3%, with greater improvement seen following iMRI-guided DBS (43.3 ±3.3%) as compared to MER-guided DBS (20.9 ±6.5%). When only the contralateral hemibody was assessed, the improvement was 46.7 ±3.1% across all patients regardless of procedure performed, or 50.3 ±3.4% and 38.0 ±6.6% for iMRI- and MER-guided DBS groups, respectively. Both groups exhibited similar reductions in LEDD (16.8 and 16.9%, respectively).

Conclusions: The use of iMRI-guided DBS in PD patients was associated with significant improvement in clinical outcomes, which were comparable to previously reported outcomes following MER-guided lead placement in the GPi. However, when we compared this group of patients to a historical cohort of patients treated with MER guided lead placement, we observed greater improvement in motor outcomes following iMRI-guided GPi-DBS.

Patient Care: This research directly compares lead location and clinical outcomes in GPi-DBS using MER- or iMRI-guidance. We show that iMRI-DBS is associated with better clinical outcomes as compared to traditional MER-DBS, thus reinforcing a role for asleep DBS in selected patients.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) describe the comparative efficacy of MER- and iMRI-guided GPi-DBS for PD at one year follow-up, 2) appreciate the differences in DBS lead placement using these techniques, and 3) discuss the role of iMRI in DBS lead placement in the pallidum of patients with PD

References: Brodsky MA, Anderson S, Murchison C, Seier M, Wilhelm J, Vederman A, et al: Clinical outcomes of asleep vs awake deep brain stimulation for Parkinson disease. Neurology 89:1944-1950, 2017 Burchiel KJ, McCartney S, Lee A, Raslan AM: Accuracy of deep brain stimulation electrode placement using intraoperative computed tomography without microelectrode recording. J Neurosurg 119:301-306, 2013 Ostrem JL, Ziman N, Galifianakis NB, Starr PA, Luciano MS, Katz M, et al: Clinical outcomes using ClearPoint interventional MRI for deep brain stimulation lead placement in Parkinson's disease. J Neurosurg 124:908-916, 2016