RF Safety for Patients with Deep Brain Stimulators

Deep brain stimulation (DBS) is an established treatment of motor disorders such as Parkinson disease that has also shown promise for the treatment of psychiatric illnesses (e.g. depression, OCD etc…). However, its mechanisms of action are not known and its clinical efficacy in psychiatric disorders is not established.

One of the reasons why this is the case is that MRI is contraindicated in DBS patient because of the heating risk associated with the currents induced on the DBS conductive lead by the MRI RF excitation. If these safety concerns could be alleviated, it is likely that MRI could lead to insights in the in vivo mechanisms of action of the DBS. Therefore, the goal of our research is to develop methods for safe MR imaging of DBS patients and to apply these methods to conduct functional, anatomical and diffusion studies on patients implanted with DBS.

Specifically, we:

  1. Develop RF excitation strategies such as pTx and rotating birdcage coil that have the potential to significantly reduce the RF currents induced on the DBS leads by MRI;
  2. Develop realistic electromagnetic (EM) simulation methodologies to accurately study the EM interactions between the MRI RF coil and DBS implants in simulation;
  3. Design and build realistic 3D-printed phantoms with implanted DBS and matched conductivity/permittivity/T1/T2 gels. We use these phantoms in thermometry studies to validate EM simulations and better characterize the DBS/MRI safety risk.
  4. Conduct functional MRI studies to characterize the effect and therapeutic and non-therapeutic DBS on the brain’s neural networks.

Group:

Larry Wald

Bastien Guerin

Ehsan Kazemivalipour