Clinical Factors Underlying the Inter-individual Variability of the Resting Motor Threshold in Navigated Transcranial Magnetic Stimulation Motor Mapping.
Correctly determining individual's resting motor threshold (rMT) is crucial for accurate and reliable mapping by navigated transcranial magnetic stimulation (nTMS), which is especially true for preoperative motor mapping in brain tumor patients. However, systematic data analysis on clinical factors underlying inter-individual rMT variability in neurosurgical motor mapping is sparse. The present study examined 14 preselected clinical factors that may underlie inter-individual rMT variability by performing multiple regression analysis (backward, followed by forward model comparisons) on the nTMS motor mapping data of 100 brain tumor patients. Data were collected from preoperative motor mapping of abductor pollicis brevis (APB), abductor digiti minimi (ADM), and flexor carpi radialis (FCR) muscle representations among these patients. While edema and age at exam in the ADM model only jointly reduced the unexplained variance significantly, the other factors kept in the ADM model (gender, antiepileptic drug intake, and motor deficit) and each of the factors kept in the APB and FCR models independently significantly reduced the unexplained variance. Hence, several clinical parameters contribute to inter-individual rMT variability and should be taken into account during initial and follow-up motor mappings. Thus, the present study adds basic evidence on inter-individual rMT variability, whereby some of the parameters are specific to brain tumor patients.
Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
Nico
N
Sollmann
Faculty of Linguistics, Philology & Phonetics, University of Oxford, Walton Street, Oxford, OX1 2HG, UK.
Noriko
N
Tanigawa
Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
Lucia
L
Bulubas
Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
Jamil
J
Sabih
TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.|Section of Neuroradiology, Department of Radiology, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.
Claus
C
Zimmer
Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.
Florian
F
Ringel
Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.
Bernhard
B
Meyer
Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany. Sandro.Krieg@tum.de.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany. Sandro.Krieg@tum.de.
Sandro M
SM
Krieg
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001931:Brain Mapping / Q000379:methods*; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
Brain tumor; Cortical mapping; Motor evoked potentials; Navigated transcranial magnetic stimulation; Presurgical motor mapping; Resting motor threshold