Integration of preoperative and intraoperative functional brain mapping ina frameless stereotactic environment for lesions near eloquent cortex - Technical note

The authors present a method of incorporating preoperative noninvasive func tional brain mapping data into the frameless stereotactic magnetic resonanc e (MR) imaging dataset used for image-guided resection of brain lesions loc ated near eloquent cortex. They report the use of functional (f)MR imaging and magnetic source (MS) imaging far preoperative mapping of eloquent corte x in difficult cases of brain tumor resection such as those in which there are large expansive masses or in which reoperations are required and the an atomy is distorted from prior treatments. To correlate methods of preoperat ive and intraoperative mapping localization directly, the authors have deve loped techniques of importing preoperative MS and fMR imaging data into an image-guided frameless stereotactic computer workstation. The data appear a s a seamless overlay on the same preoperative volumetric MR imaging dataset used for stereotactic guidance during the operation. Intraoperatively iden tified functional locations mapped by cortical stimulation are recorded as digitally registered points. This approach should prove useful in assessing the accuracy and reliability of various preoperative functional brain mapp ing techniques.