First clinical results of intraoperative high-field magnetic resonance imaging supported by neuronavigation

A new setup for intraoperative imaging, combining the benefits of high-field magnetic resonance (MR) imaging with microscope-based neuronavigation, providing anatomical and functional guidance was established by adapting a rotating operating table to a 1.5 T MR scanner, placed in a radiofrequency-shielded operating theatre. The navigation microscope placed in the 5 G zone in combination with a ceiling mounted navigation system enables integrated microscope-based neuronavigation. A total of 126 patients, mainly gliomas and pituitary adenomas, were investigated. In 29% of all patients, intraoperative MR imaging resulted in a repeated inspection of the surgical field with a modification of the surgical strategy. In 62 patients, microscope-based navigation was used, in 21 functional data were integrated. Navigational accuracy was not impeded by the magnetic fringe field. Imaging quality was not disturbed by the operating environment; there was hardly a difference in imaging quality between pre- and intraoperative scans. Intraoperative workflow with patient transport for imaging was straightforward. We did not encounter any untoward events due to the high magnetic field. Standard high-field MR scanners can be successfully adapted to an operating environment including integrated neuronavigational support. Their intraoperative application offers increased image quality and a broad spectrum of different imaging modalities, compared to previous low-field systems.