Ultrahigh-Magnitude Brain Magnetic Resonance Imaging Scan on Rhesus Monkeys With Implanted Deep Brain Stimulation Hardware.

BACKGROUND: Patients with implanted deep brain stimulation (DBS) hardware are prohibited from undergoing magnetic resonance imaging (MRI) scans at magnitudes greater than 1.5 T to avoid potential MRI-related heating injury. Whether DBS devices are compatible with higher field MRI scanning is unknown. This study aimed to investigate whether 7.0 T and 3.0 T MRI scans can be safely performed on rhesus monkeys with implanted DBS devices. METHODS: Eight male rhesus monkeys were included in this study and stereotactically implanted with DBS devices in the left anterior thalamus. Two weeks after DBS device implantation, 7.0 T and 3.0 T MRI scans were performed. The monkeys were observed for 72 hours. After explantation of the DBS system, 7.0 T MRI was repeated to determine potential lesions. Hematoxylin and eosin staining and transmission electron microscopy were conducted to assess pathological alterations. RESULTS: In both groups, the monkeys exhibited no behavioral changes related to neurological deficits. Post-explantation MRI showed no malacia foci surrounding the DBS tracks. Additionally, neither hematoxylin and eosin staining nor transmission electron microscopy showed clear injury near the DBS leads. CONCLUSION: These results indicate that no obvious heating injury was induced in the tissue surrounding the DBS leads by the 7.0 T and 3.0 T MRI scans. Although the results of this study may not be generalizable, these data suggest that patients with implanted DBS devices can undergo even 7.0 T MRI without risk of brain injury.