There is a growing interest in the use of chronic deep brain stimulation (DBS) of the thalamus, globus pallidus, and the subthalamic nucleus for the treatment of medically refractory movement disorders and other neurological and psychiatric conditions. The number of patients undergoing DBS surgeries is anticipated to increase rapidly. Use of magnetic resonance imaging (MRI) is crucial for the management of patients with DBS. Critical studies include verification of lead position, assessment of patients with poor outcomes, evaluation for other intracranial pathologies, and performing functional MRI studies. However, electronically activated devices are generally considered to be contraindicated for patients undergoing MRI, based on reports of adverse effects in the literature. Our primary hypothesis is that parameters can be defined that will enable safe MR imaging in patients with DBS. Building upon our preliminary data, We intend to conduct a comprehensive safety analysis, functional assessment of the stimulation devices, and evaluation of the artifacts produced by the DBS. We will use 1.5 Tesla and 3Tesla MR systems, body radio frequency (RF) and head RF coils to conduct all experiments. Specifically, in-vitro experiments will be performed to assess DBS magnetic field interactions (translational attraction and torque), MRI-related heating (including computer modeling), induced electrical currents, and identification of any effects on device functionality. The artifacts produced by the DBS electrodes will also be quantified. The identification of safe MRI parameters will enable patients with neurostimulation systems to routinely undergo diagnostic MR procedures and allow the use of this important imaging modality for the optimal localization of DBS electrodes.
