Plastic relocation of motor cortex in a patient with LGG (low grade glioma) confirmed by NBS (navigated brain stimulation).

We report on a patient with LGG, in whom NBS mapping confirmed relocation of the primary motor cortex (M1) concurrent with multistage surgery. Comparing the NBS results at 18 months with the initial results revealed that the M1 representation had shifted from the precentral to the postcentral gyrus. The patient underwent a third surgical intervention. Intraoperative direct cortical stimulation (DCS) confirmed the shift of the M1. Plastic changes in M1 localization permitted complete tumour removal without neurological sequela. To our knowledge, this is the first report on a LGG patient where induced brain plasticity has been confirmed by NBS mapping.