Navigation system based on intraoperative diffusion weighted imaging using open MRI

When performing surgery for malignant brain tumor that is close to pyramidal tract, it is an important issue how to preserve motor function. While diffusion tensor (DT) imaging on magnetic resonance imaging (MRI) can visualize course of nerve bundle, surgical navigation based on preoperative image may have considerable position error because of brain shift. We visualized pyramidal tract by intraoperative diffusion weighted (DW) imaging using 0.3T open MRI in tumor removal close to the fiber and performed surgery using the navigation based on the image. The surgeon was able to perform surgery confirming pyramidal tract localization corresponding to brain shift demonstrated on the navigation image.