Neurophysiological examination combined with functional intraoperative navigation using TMS in patients with brain tumor near the central region—a pilot study

Abstract

Feasibility and value of non-invasive transcranial magnetic brain stimulation (TMS MAGVENTURE® MagPro R30 Denmark) for preoperative diagnosis and surgical planning of brain tumor operations in everyday clinical practice. A prospective monocentric study was conducted, which included preoperative neurological and electrophysiological examination, TMS, and display of functional data in the navigation system (LOCALITE® TMS Navigator Germany). During surgery, the TMS data were correlated with the intraoperative monitoring (IOM). Twenty-four hours to 96 h and after at least 3 months, follow-ups with neurological, electrophysiological examinations and TMS stimulation were performed. Twenty-five patients with tumors in or near by the primary motor cortex region were included in the study. Twenty-one patients completed preoperative and first postoperative TMS and the neurological examination. Eight of 21 patients showed slight worsening of primary motor cortex function, 8 patients had an unchanged state, and 4 patients showed an improvement early after surgery. The changes of the electrophysiological examination like significant delay of the latency and/or reduced amplitudes matched well with the postoperative neurological outcome: if patients showed a worsening of the SEP’s and MEP’s, the postoperative results revealed deterioration. A preoperatively performed TMS using the MAGVENTURE® MagPro R30 and the LOCALITE® TMS Navigator could be established in our clinical daily practice and allowed a safe and reliable mapping of the primary motor cortex in order to minimize the risk of postoperative neurological deficits and improve the neurological outcome of the patients.