Implants talk to each-other: RF heating changes when two DBS leads are present simultaneously during MRI.

Area of Science:

• Medical Physics
• Neurosurgery
• Biomedical Engineering

Background:

• Deep brain stimulation (DBS) is a key treatment for Parkinson's disease and other neurological disorders.
• Current MRI safety assessments for DBS implants evaluate leads individually, neglecting inter-lead interactions (crosstalk).

Purpose of the Study:

• To investigate the impact of crosstalk between bilateral DBS leads on radiofrequency (RF) power deposition during MRI.
• To assess how lead configuration affects RF power deposition and potential thermal risks.

Main Methods:

• Patient-specific lead trajectories were obtained from CT images for numerical simulations.
• RF power deposition at the lead tip was compared for unilateral and bilateral DBS implant scenarios.
• Phantom experiments with simplified DBS lead systems were conducted to validate simulation findings.

Main Results:

• Numerical simulations showed RF power deposition at the DBS lead tip can increase by up to sixfold with bilateral leads compared to unilateral.
• Experimental measurements confirmed the existence of crosstalk between DBS leads.
• The presence of multiple leads can alter power deposition, potentially increasing or decreasing local tissue heating.

Conclusions:

• MRI safety evaluations for DBS implants must consider lead crosstalk.
• Bilateral DBS lead configurations can significantly influence RF power deposition, impacting patient safety during MRI scans.
• Further research is needed to refine MRI protocols for patients with bilateral DBS implants.