MR-guided and MR-monitored neurosurgical procedures at 1.5 T.
A combined MR suite and operating room (MR-OR) has been developed and extensively assessed for its use in a wide spectrum of therapeutic applications. Equipped with a 1.5 T short bore clinical MR scanner and standard neurosurgical OR equipment, in this MR surgical suite, surgeons can obtain intraoperative planar and volumetric MR images with superior soft tissue contrast and spatial resolution for surgical planning, guidance, and monitoring. Besides MR morphologic imaging capability, blood oxygen level-dependent functional MRI and proton MR spectroscopic imaging have been demonstrated intraoperatively in the same MR-OR to aid in surgical planning and guide tumor resections. A perspective surgical navigation device and remotely operated instrument have been developed and successfully used to assist surgeons in aligning and introducing biopsy needles under fluoroscopic MRI in brain biopsy procedures. Furthermore, surgical complications can be assessed immediately before the closure. There are numerous advantages offered by this unprecedented MR-guided surgical approach, most of which are demonstrated and presented herein. Since 1997, >270 neurosurgical cases (42% brain biopsies, 25% tumor resections, 11% functional neurosurgeries, 10% cyst drainages and shunt placements, and 12% others) have been performed in the MR-OR with a <1% overall complication rate. The tumor recurrence rate for the MR-guided surgical approach is significantly less than that of the conventional one. Exemplary neurosurgical cases that have been performed in the MR-OR suite within the last 24 months are included. Overall, this high magnetic field approach to the MR-guided minimally invasive surgical procedures has been shown to be practical and acceptable to neurosurgeons as well as to neuroradiologists for a wide range of neurosurgical and neuroradiologic applications.