TY - JOUR
T1 - Tumor-Specific Alterations in Motor Cortex Excitability and Tractography of the Corticospinal Tract-A Navigated Transcranial Magnetic Stimulation Study
AU - Eibl, Thomas
AU - Schrey, Michael
AU - Liebert, Adrian
AU - Ritter, Leonard
AU - Lange, Ruediger
AU - Steiner, Hans-Herbert
AU - Schebesch, Karl-Michael
N1 - alle außer Lange: Department of Neurosurgery, Paracelsus Medical University, 90471 Nuremberg, Germany; Lange: Department of Neurology, Paracelsus Medical University, 90471 Nuremberg, Germany
PY - 2024/7
Y1 - 2024/7
N2 - Background: Non-invasive brain mapping using navigated transcranial magnetic stimulation (nTMS) is a valuable tool prior to resection of malignant brain tumors. With nTMS motor mapping, it is additionally possible to analyze the function of the motor system and to evaluate tumor-induced neuroplasticity. Distinct changes in motor cortex excitability induced by certain malignant brain tumors are a focal point of research. Methods: A retrospective single-center study was conducted involving patients with malignant brain tumors. Clinical data, resting motor threshold (rMT), and nTMS-based tractography were evaluated. The interhemispheric rMT-ratio (rMT(Tumor)/rMT(Control)) was calculated for each extremity and considered pathological if it was >>110% or <<90%. Distances between the corticospinal tract and the tumor (lesion-to-tract-distance - LTD) were measured. Results: 49 patients were evaluated. 16 patients (32.7%) had a preoperative motor deficit. The cohort comprised 22 glioblastomas (44.9%), 5 gliomas of Classification of Tumors of the Central Nervous System (CNS WHO) grade 3 (10.2%), 6 gliomas of CNS WHO grade 2 (12.2%) and 16 cerebral metastases (32.7%). 26 (53.1%) had a pathological rMT-ratio for the upper extremity and 35 (71.4%) for the lower extremity. All patients with tumor-induced motor deficits had pathological interhemispheric rMT-ratios, and presence of tumor-induced motor deficits was associated with infiltration of the tumor to the nTMS-positive cortex (p = 0.04) and shorter LTDs (all p << 0.021). Pathological interhemispheric rMT-ratio for the upper extremity was associated with cerebral metastases, but not with gliomas (p = 0.002). Conclusions: Our study underlines the diagnostic potential of nTMS motor mapping to go beyond surgical risk stratification. Pathological alterations in motor cortex excitability can be measured with nTMS mapping. Pathological cortical excitability was more frequent in cerebral metastases than in gliomas.
AB - Background: Non-invasive brain mapping using navigated transcranial magnetic stimulation (nTMS) is a valuable tool prior to resection of malignant brain tumors. With nTMS motor mapping, it is additionally possible to analyze the function of the motor system and to evaluate tumor-induced neuroplasticity. Distinct changes in motor cortex excitability induced by certain malignant brain tumors are a focal point of research. Methods: A retrospective single-center study was conducted involving patients with malignant brain tumors. Clinical data, resting motor threshold (rMT), and nTMS-based tractography were evaluated. The interhemispheric rMT-ratio (rMT(Tumor)/rMT(Control)) was calculated for each extremity and considered pathological if it was >>110% or <<90%. Distances between the corticospinal tract and the tumor (lesion-to-tract-distance - LTD) were measured. Results: 49 patients were evaluated. 16 patients (32.7%) had a preoperative motor deficit. The cohort comprised 22 glioblastomas (44.9%), 5 gliomas of Classification of Tumors of the Central Nervous System (CNS WHO) grade 3 (10.2%), 6 gliomas of CNS WHO grade 2 (12.2%) and 16 cerebral metastases (32.7%). 26 (53.1%) had a pathological rMT-ratio for the upper extremity and 35 (71.4%) for the lower extremity. All patients with tumor-induced motor deficits had pathological interhemispheric rMT-ratios, and presence of tumor-induced motor deficits was associated with infiltration of the tumor to the nTMS-positive cortex (p = 0.04) and shorter LTDs (all p << 0.021). Pathological interhemispheric rMT-ratio for the upper extremity was associated with cerebral metastases, but not with gliomas (p = 0.002). Conclusions: Our study underlines the diagnostic potential of nTMS motor mapping to go beyond surgical risk stratification. Pathological alterations in motor cortex excitability can be measured with nTMS mapping. Pathological cortical excitability was more frequent in cerebral metastases than in gliomas.
KW - Functional imaging
KW - Glioma
KW - nTMS motor mapping
KW - Navigated transcranial magnetic stimulation
KW - Neuronavigation
KW - Neurooncology
UR - https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=pmu_pure&SrcAuth=WosAPI&KeyUT=WOS:001302767500018&DestLinkType=FullRecord&DestApp=WOS_CPL
U2 - 10.31083/j.jin2307132
DO - 10.31083/j.jin2307132
M3 - Original Article
C2 - 39082301
SN - 0219-6352
VL - 23
JO - Journal of Integrative Neuroscience
JF - Journal of Integrative Neuroscience
IS - 7
M1 - 132
ER -