Evaluation of preoperative high magnetic field motor functional MRI (3 Tesla) in glioma patients by navigated electrocortical stimulation and postoperative outcome

Abstract

The validity of 3 Tesla motor functional magnetic resonance imaging (fMRI) in patients with gliomas involving the primary motor cortex was investigated by intraoperative navigated motor cortex stimulation (MCS). Methods: Twenty two patients (10 males, 12 females, mean age 39 years, range 10-65 years) underwent preoperative fMRI studies, performing motor tasks including hand, foot, and mouth movements. A recently developed high field clinical fMRI technique was used to generate pre-surgical maps of functional high risk areas defining a motor focus. Motor foci were tested for validity by intraoperative motor cortex stimulation (MCS) employing image fusion and neuronavigation. Clinical outcome was assessed using the Modified Rankin Scale. Results: FMRI motor foci were successfully detected in all patients preoperatively. In 17 of 22 patients (77.3%), a successful stimulation of the primary motor cortex was possible. All 17 correlated patients showed 100% agreement on MCS and fMRI motor focus within 10 mm. Technical problems during stimulation occurred in three patients (13.6%), no motor response was elicited in two (9.1%), and MCS induced seizures occurred in three (13.6%). Combined fMRI and MCS mapping results allowed large resections in 20 patients (91%) (gross total in nine (41%), subtotal in 11 (50%)) and biopsy in two patients (9%). Pathology revealed seven low grade and 15 high grade gliomas. Mild to moderate transient neurological deterioration occurred in six patients, and a severe hemiparesis in one. All patients recovered within 3 months (31.8% transient, 0% permanent morbidity). Conclusions: The validation of clinically optimised high magnetic field motor fMRI confirms high reliability as a preoperative and intraoperative adjunct in glioma patients selected for surgery within or adjacent to the motor cortex.

The role of functional magnetic resonance imaging in brain surgery

“…Bizzi et al 7 reported sensitivity and specificity of 88 and 87%, respectively, when hand motor function on fMR imaging was compared with ESM (both modalities were considered to match if fMR imaging activation was present within 1 cm of a positive ESM site). With similar criteria, Roessler et al 75 found 100% agreement in 17 patients with low-or high-grade gliomas. They were able to detect fMR imaging activation in the handknob region in all patients.…”

Integration of functional neuronavigation and intraoperative MRI in surgery for drug-resistant extratemporal epilepsy close to eloquent brain areas

“…Their accuracy and specificity were discussed in recent studies. 1,28,36,37 Eloquent cortex that can be mapped using fMRI includes the primary motor and somatosensory regions, and Broca and Wernicke areas along with hemispheric language lateralization and their connectivity within the CNS by using DTI for displaying pyramidal, language, and visual tracts. 32,51 Intraoperative high-field (≥ 1.5-T) MRI systems are well established in operating rooms and were used in glioma surgery or frameless stereotaxy.…”

“…13,17,37 Additionally, white matter tracts can be detected ("fibertracking") by DTI and included in the neuronavigation, which we termed "multimodal navigation," 31 mainly to avoid awake craniotomies, which are cumbersome for the patient and surgeon.…”

Non-rigid alignment of pre-operative MRI, fMRI, and DT-MRI with intra-operative MRI for enhanced visualization and navigation in image-guided neurosurgery

“…Moreover, cortical stimulation is a demanding, time consuming, and costly procedure and as such is often not possible during surgery. Therefore, because fMRI of motor and language tasks is feasible in patients with cerebral tumors (Mueller et al 1996), several groups have proposed the integration of functional data into the neuronavigation system in recent years (Krishnan et al 2004, Gralla et al 2003, Jannin et al 2002, Roessler et al 2005, Reithmeier et al 2003, Talos et al 2003, O'Shea et al 2006. And strong evidence that a more radical tumor resection may be achieved by using fMRI information during neurosurgery has been demonstrated by Krishnan et al 2004, Haberg et al 2004 Diffusion tensor imaging (DTI) has recently emerged as a potentially valuable tool for preoperative planning (Tummala et al 2004, Field et al 2004, Clark et al 2003, Wieshmann et al 2000, Moller-Hartmann et al 2002, Coenen et al 2003 and postoperative follow-up (Alexander et al 2003) of surgically treated brain tumors and vascular malformations.…”