OBJECTIVE High-field intraoperative MR (ioMRI) has become increasingly available in neurosurgery centers. There is little experience with the combination of ioMRI with intraoperative neurophysiological neuromonitoring (IONM). We provide a first series of pediatric patients undergoing brain tumor surgery with 3T ioMRI and IONM.
METHODS We conducted a pilot study were we included all consecutive children operated for brain tumors between October 2013 and April 2016 where concomitant ioMRI and somatosensory evoked potentials (SEP) and motor evoked potentials (MEP) were used. All cases were retrospectively analysed concerning neuromonitoring findings and related complications.
RESULTS During a period of 30 months, 17 children (mean age 8.4 years; 3 females) were operated meeting the criteria. A total of 483 IONM needles were left in place during ioMRI. Of these needles, 119 were located on the scalp, 94 above the chest, and 270 below the chest. Two complications with skin burns (first degree) were observed. In all patients, neuromonitoring was still reliable after MRI. In one case, a threshold increase for MEP-stimulation (20 mA) was necessary after ioMRI; in two cases a reduction of 50% of the SEP amplitude at the end of the surgery was observed, when compared to the values obtained before ioMRI.
CONCLUSIONS The combination of ioMRI and IONM can be safely performed in the pediatric population. IONM data acquisition after ioMRI was feasible and remained reliable.