Supplementary Material for: The Rate of Magnetic Resonance Imaging in Patients with Deep Brain Stimulation

Background: For Parkinson's disease (PD), essential tremor (ET), and dystonia patients with deep brain stimulation (DBS) implants, magnetic resonance imaging (MRI) requires additional safety considerations due to potentially hazardous interactions. Objective: A propensity-matched cohort of DBS-implanted patients was analyzed to determine the likelihood of needing MRI. Methods: Patients with new DBS full-system implants (n = 576) were identified in the Truven Health MarketScan® Commercial Claims and Medicare Supplemental Databases (2009-2012). Patients diagnosed with PD, ET, or dystonia and no DBS implant were identified (DBS-indicated patients: n = 11,216). The DBS-indicated patients were continuously enrolled for 4 years and matched for age, gender, and propensity score based on comorbid conditions to DBS-implanted patients (n = 4,878 and 543, respectively). A Kaplan-Meier survival curve of time to first MRI was extrapolated to 10 years. Results: An estimated 56-57% of DBS-indicated patients need an MRI within 5 years and 66-75% within 10 years after implantation. While 92% of DBS-implanted patients' MRI after implantation was of the head, for DBS-indicated patients, 62% of MRIs were of the body, potentially unrelated to the primary diagnosis. Conclusions: This analysis highlights the projected utilization of MRI in the DBS population for head and full-body images.