Project Details
Projekt
TMS-EEG: A New Method to Uncover Neuroplastic Impacts of Brain Tumors
Applicant
Dr. Melina Engelhardt
Subject Area
Clinical Neurology; Neurosurgery and Neuroradiology
Term
since 2026
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 578950026
Patients with brain tumors that appear identical on structural imaging can exhibit diverse functional impairments. Similarly, the surgical removal of these tumors often results in a diverse range of functional deficits. This variability poses significant challenges in clinical practice, particularly in defining surgical risks and determining resection margins. These concerns are increasingly critical with the growing trend of supramarginal resection, which risks removing healthy, functional tissue without sufficient preoperative functional mapping. Hence, to preserve patients' neurological health, examining the functionality, connectivity and recovery potential of tissues at risk of surgical damage is crucial. Transcranial magnetic stimulation (TMS) combined with electroencephalography (EEG) has been introduced in a wide range of neurological diseases to characterize the impact of lesions on the integrity and connectivity of the brain without requiring behavioral correlates. I have recently applied TMS-EEG in brain tumor patients, revealing distinct alterations in cortical reactivity in tumoral and peritumoral areas, which were also predictive of postoperative recovery of brain activity. Now, I aim to build on these findings by employing a high-resolution grid mapping using the novel multi-locus TMS (mTMS) to analyze tumoral, peritumoral, and healthy brain areas. Stimulation, guided by tractography, will target brain regions directly affected by the tumor, indirectly affected by structural connections to the tumor, and unaffected by the tumor, thereby elucidating the mechanisms underlying changes in reactivity and connectivity. The semi-automated application of mTMS ensures personalized, robust and time-efficient targeting of the stimulation. Fifteen patients with gliomas will undergo mTMS-EEG examinations before and 3 months post-surgery. Each patient will receive stimulation over a grid of preselected points on the tumoral and healthy hemispheres. Cortical reactivity and connectivity measured by EEG will be compared between different stimulation locations and tissue types (healthy, peritumoral, tumoral). Further, the association between peritumoral reactivity and the functional status of patients pre- and postoperatively will be assessed. This new approach has the potential to revolutionize neurosurgical planning, especially in the age of supramarginal resections and increased awareness of the need to preserve complex higher neurocognitive functions. mTMS-EEG makes it possible to characterize brain functionality in vulnerable neurosurgical patients, who may be unable to fully cooperate, without the need for demanding behavioral correlates.
DFG Programme
Fellowship
International Connection
Finland
