An Optimized System for Interventional Magnetic Resonance Imaging-Guided Stereotactic Surgery: Preliminary Evaluation of Targeting Accuracy

BACKGROUND: Deep brain stimulation electrode placement with interventional magnetic resonance imaging (MRI) has previously been reported using a commercially available skull-mounted aiming device (Medtronic Nexframe MR) and native MRI scanner software. This first-generation method has technical limitations that are inherent to the hardware and software used. A novel system (SurgiVision ClearPoint) consisting of an aiming device (SMARTFrame) and software has been developed spe-cifically for interventional MRI, including deep brain stimulation. OBJECTIVE: To report a series of phantom and cadaver tests performed to determine the capability, preliminary accuracy, and workflow of the system. METHODS: Eighteen experiments using a water phantom were used to determine the predictive accuracy of the software. Sixteen experiments using a gelatin-filled skull phantom were used to determine targeting accuracy of the aiming device. Six proce-dures in 3 cadaver heads were performed to compare the workflow and accuracy of ClearPoint with Nexframe MR. RESULTS: Software prediction experiments showed an average error of 0.9 6 0.5 m