Application of presurgical navigated transcranial magnetic stimulation motor mapping for adjuvant radiotherapy planning in patients with high-grade gliomas

Background: Navigated transcranial magnetic stimulation (nTMS) is a well establish a noninvasive method for preoperative brain motor mapping. We commonly use magnetic resonance imaging (MRI) to supply the nTMS system. In some cases, MRI is not possible or available, and the use of computed tomography (CT) is necessary. We present the first report describing the association of CT and nTMS motor mapping for brain lesion resection. Case Description: CT imaging of a 59-year-old man suffering from acquired immune deficiency syndrome for 17 years, presenting with seizure and right hemiparesis, revealed a small single hypodense ring-enhancing lesion in the left central sulci suggesting cerebral toxoplasmosis. After 3 weeks of neurotoxoplasmosis treatment, due to four consecutive tonic-clonic seizures, a new CT scan was performed and showed no lesion changes. MRI was in maintenance at that time. Infectious diseases department suggested a brain lesion biopsy. Due to lesion’s location, we decided to perform a presurgical nTMS motor mapping. After a small craniotomy, we could precisely locate and safely totally remove the lesion. The pathology report revealed a high suspicious toxoplasmosis pattern. The patient was discharged after 2 days and continued toxoplasmosis treatment. After 6 months follow-up, he showed no signs of any procedure-related deficits or radiological recurrence. Conclusion: We report the feasibility and applicability of nTMS motor mapping using CT scan as an image source. It gives neurosurgeons another possibility to perform motor mapping for brain lesion removal, especially when MRI is not available or feasible.

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The effect of coil placement and orientation on the assessment of focal excitability in motor mapping with navigated transcranial magnetic stimulation

Journal of Neuroscience Methods ◽

10.1016/j.jneumeth.2019.108521 ◽

2020 ◽

Vol 331 ◽

pp. 108521 ◽

Cited By ~ 10

Author(s):

Jusa Reijonen ◽

Laura Säisänen ◽

Mervi Könönen ◽

Ali Mohammadi ◽

Petro Julkunen

Keyword(s):

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Navigated Transcranial Magnetic Stimulation ◽

Motor Mapping

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Navigated transcranial magnetic stimulation mapping of the motor cortex for preoperative diagnostics in pediatric epilepsy

Journal of Neurosurgery Pediatrics ◽

10.3171/2021.2.peds20901 ◽

2021 ◽

pp. 1-8

Author(s):

Severin Schramm ◽

Aashna Mehta ◽

Kurtis I. Auguste ◽

Phiroz E. Tarapore

Keyword(s):

Transcranial Magnetic Stimulation ◽

Motor Cortex ◽

Magnetic Stimulation ◽

Pediatric Patients ◽

Refractory Epilepsy ◽

Pediatric Epilepsy ◽

Epilepsy Patient ◽

Navigated Transcranial Magnetic Stimulation ◽

Motor Mapping ◽

Medically Refractory Epilepsy

OBJECTIVE Navigated transcranial magnetic stimulation (nTMS) is a noninvasive technique often used for localization of the functional motor cortex via induction of motor evoked potentials (MEPs) in neurosurgical patients. There has, however, been no published record of its application in pediatric epilepsy surgery. In this study, the authors aimed to investigate the feasibility of nTMS-based motor mapping in the preoperative diagnostic workup within a population of children with medically refractory epilepsy. METHODS A single-institution database was screened for preoperative nTMS motor mappings obtained in pediatric patients (aged 0 to 18 years, 2012 to present) with medically refractory epilepsy. Patient clinical data, demographic information, and mapping results were extracted and used in statistical analyses. RESULTS Sixteen patients met the inclusion criteria, 15 of whom underwent resection. The median age was 9 years (range 0–17 years). No adverse effects were recorded during mapping. Specifically, no epileptic seizures were provoked via nTMS. Recordings of valid MEPs induced by nTMS were obtained in 10 patients. In the remaining patients, no MEPs could be elicited. Failure to generate MEPs was associated significantly with younger patient age (r = 0.8020, p = 0.0001863). The most frequent seizure control outcome was Engel Epilepsy Surgery Outcome Scale class I (9 patients). CONCLUSIONS Navigated TMS is a feasible, effective, and well-tolerated method for mapping the motor cortex of the upper and lower extremities in pediatric patients with epilepsy. Patient age modulates elicitability of MEPs, potentially reflecting various stages of myelination. Successful motor mapping has the potential to add to the existing presurgical diagnostic workup in this population, and further research is warranted.

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Preoperative mapping of the eloquent cortical areas using navigated transcranial magnetic stimulation combined with intraoperative neuronavigation for intracerebral lesions

Romanian Neurosurgery ◽

10.2478/romneu-2018-0002 ◽

2018 ◽

Vol 32 (1) ◽

pp. 16-24

Author(s):

G. Petrescu ◽

Cristina Gorgan ◽

A. Giovani ◽

F.M. Brehar ◽

R.M. Gorgan

Keyword(s):

Transcranial Magnetic Stimulation ◽

Surgical Resection ◽

Magnetic Stimulation ◽

Neurological Deficits ◽

Navigated Transcranial Magnetic Stimulation ◽

Mapping Procedure ◽

Motor Mapping ◽

Eloquent Areas ◽

Preoperative Mapping ◽

Eloquent Area

Abstract Introduction: Maximal surgical resection with the preservation of cortical functions is the treatment of choice for brain tumors. Achieving these objectives is especially difficult when the tumor is located in an eloquent area. Navigated transcranial magnetic stimulation (nTMS) is a modern non-invasive, preoperative method for defining motor and speech eloquent areas. Material and methods: Patients with tumors located in motor and speech eloquent areas who presented at our institution between March 2017 and December 2017 were prospectively included. Exclusion criteria were frequent generalized epileptic seizures and cranial implants. For lesions involving motor eloquent areas we performed a nTMS motor mapping and for lesions involving speech eloquent areas we supplemented the motor mapping with speech and language mapping. MR images were exported from the nTMS system in a DICOM format and then loaded in the intraoperative neuronavigation system. Based on these findings, the optimal entry point and trajectory were determined, in order to achieve a maximum surgical resection of the lesion, while avoiding new post-operative neurological deficits. Results: Nineteen patients underwent an nTMS brain mapping procedure between March 2017 and December 2017. In all cases a motor mapping procedure was done, but only in eight cases a speech mapping was also performed. Three patients presented new minor postoperatory deficits that consecutively remitted. The rest of the patients presented no added neurological deficits after surgery. In five cases the preexistent deficit was ameliorated after surgery and in three cases the deficit remitted. In one patient there was no improvement in the neurologic deficit after surgery. Conclusion: nTMS is a reliable tool for the preoperative planning of eloquent area lesions. It must be taken into account that functional areas have a high individual variability. Therefore, knowing preoperatively the extent of the eloquent area helps the neurosurgeon adapt the surgical approach in order to obtain a better functional outcome.

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Navigated Transcranial Magnetic Stimulation Motor Mapping Usefulness in the Surgical Management of Patients Affected by Brain Tumors in Eloquent Areas: A Systematic Review and Meta-Analysis

Frontiers in Neurology ◽

10.3389/fneur.2021.644198 ◽

2021 ◽

Vol 12 ◽

Author(s):

Giuseppe Emmanuele Umana ◽

Gianluca Scalia ◽

Francesca Graziano ◽

Rosario Maugeri ◽

Nicola Alberio ◽

...

Keyword(s):

Systematic Review ◽

Transcranial Magnetic Stimulation ◽

Brain Tumors ◽

Brain Mapping ◽

Magnetic Stimulation ◽

Neurophysiological Monitoring ◽

Invasive Technique ◽

Navigated Transcranial Magnetic Stimulation ◽

Motor Mapping ◽

Mesh Terms

Background: The surgical strategy for brain glioma has changed, shifting from tumor debulking to a more careful tumor dissection with the aim of a gross-total resection, extended beyond the contrast-enhancement MRI, including the hyperintensity on FLAIR MR images and defined as supratotal resection. It is possible to pursue this goal thanks to the refinement of several technological tools for pre and intraoperative planning including intraoperative neurophysiological monitoring (IONM), cortico-subcortical mapping, functional MRI (fMRI), navigated transcranial magnetic stimulation (nTMS), intraoperative CT or MRI (iCT, iMR), and intraoperative contrast-enhanced ultrasound. This systematic review provides an overview of the state of the art techniques in the application of nTMS and nTMS-based DTI-FT during brain tumor surgery.Materials and Methods: A systematic literature review was performed according to the PRISMA statement. The authors searched the PubMed and Scopus databases until July 2020 for published articles with the following Mesh terms: (Brain surgery OR surgery OR craniotomy) AND (brain mapping OR functional planning) AND (TMS OR transcranial magnetic stimulation OR rTMS OR repetitive transcranial stimulation). We only included studies regarding motor mapping in craniotomy for brain tumors, which reported data about CTS sparing.Results: A total of 335 published studies were identified through the PubMed and Scopus databases. After a detailed examination of these studies, 325 were excluded from our review because of a lack of data object in this search. TMS reported an accuracy range of 0.4–14.8 mm between the APB hotspot (n1/4 8) in nTMS and DES from the DES spot; nTMS influenced the surgical indications in 34.3–68.5%.Conclusion: We found that nTMS can be defined as a safe and non-invasive technique and in association with DES, fMRI, and IONM, improves brain mapping and the extent of resection favoring a better postoperative outcome.

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