Comparison of Navigated Transcranial Magnetic Stimulation to Direct Electrical Stimulation for Mapping the Motor Cortex Prior to Brain Tumor Resection

Abstract BACKGROUND: Brain tumor surgery near the motor cortex requires careful planning to achieve the optimal balance between completeness of tumor resection and preservation of motor function. Navigated transcranial magnetic stimulation (nTMS) can be used to map functionally essential motor areas preoperatively. OBJECTIVE: To evaluate how much influence, benefit, and impact nTMS has on the surgical planning for tumors near the motor cortex. METHODS: This study reviewed the records of 73 patients with brain tumors in or near the motor cortex, mapped preoperatively with nTMS. The surgical team prospectively classified how much influence the nTMS results had on the surgical planning. Stepwise regression analysis was used to explore which factors predict the amount of influence, benefit, and impact nTMS has on the surgical planning. RESULTS: The influence of nTMS on the surgical planning was as follows: it confirmed the expected anatomy in 22% of patients, added knowledge that was not used in 23%, added awareness of high-risk areas in 27%, modified the approach in 16%, changed the planned extent of resection in 8%, and changed the surgical indication in 3%. CONCLUSION: nTMS had an objective benefit on the surgical planning in one fourth of the patients and a subjective benefit in an additional half of the patients. It had an impact on the surgery itself in just more than half of the patients. By mapping the spatial relationship between the tumor and functional motor cortex, nTMS improves surgical planning for tumors in or near the motor cortex.

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The verb and noun test for peri-operative testing (VAN-POP): standardized language tests for navigated transcranial magnetic stimulation and direct electrical stimulation

Acta Neurochirurgica ◽

10.1007/s00701-019-04159-x ◽

2019 ◽

Vol 162 (2) ◽

pp. 397-406 ◽

Cited By ~ 2

Author(s):

Ann-Katrin Ohlerth ◽

Antonio Valentin ◽

Francesco Vergani ◽

Keyoumars Ashkan ◽

Roelien Bastiaanse

Keyword(s):

Electrical Stimulation ◽

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Language Skills ◽

Word Retrieval ◽

Direct Electrical Stimulation ◽

Navigated Transcranial Magnetic Stimulation ◽

Single Word ◽

Language Mapping ◽

Language Tests

Abstract Background Protocols for intraoperative language mapping with direct electrical stimulation (DES) often include various language tasks triggering both nouns and verbs in sentences. Such protocols are not readily available for navigated transcranial magnetic stimulation (nTMS), where only single word object naming is generally used. Here, we present the development, norming, and standardization of the verb and noun test for peri-operative testing (VAN-POP) that measures language skills more extensively. Methods The VAN-POP tests noun and verb retrieval in sentence context. Items are marked and balanced for several linguistic factors known to influence word retrieval. The VAN-POP was administered in English, German, and Dutch under conditions that are used for nTMS and DES paradigms. For each language, 30 speakers were tested. Results At least 50 items per task per language were named fluently and reached a high naming agreement. Conclusion The protocol proved to be suitable for pre- and intraoperative language mapping with nTMS and DES.

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Navigated Transcranial Magnetic Stimulation and Functional Magnetic Resonance Imaging: Advanced Adjuncts in Preoperative Planning for Central Region Tumors

Neurosurgery ◽

10.1227/neu.0b013e31820b528c ◽

2011 ◽

Vol 68 (5) ◽

pp. 1317-1325 ◽

Cited By ~ 90

Author(s):

Marie-Thérèse Forster ◽

Elke Hattingen ◽

Christian Senft ◽

Thomas Gasser ◽

Volker Seifert ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Transcranial Magnetic Stimulation ◽

Magnetic Resonance ◽

Motor Cortex ◽

Magnetic Stimulation ◽

Tumor Resection ◽

Preoperative Assessment ◽

Navigated Transcranial Magnetic Stimulation ◽

Functional Magnetic Resonance ◽

Resonance Imaging

Abstract BACKGROUND: Tumor resection in the vicinity of the motor cortex poses a challenge to all neurosurgeons. For preoperative assessment of eloquent cortical areas, functional magnetic resonance imaging (fMRI) is used, whereas intraoperatively, direct cortical stimulation (DCS) is performed. Navigated transcranial magnetic stimulation (nTMS) is comparable to DCS in activating cortical pyramidal neurons. OBJECTIVE: To evaluate the reliability of nTMS compared with fMRI and DCS for preoperative resection planning of centrally located tumors. METHODS: In a prospective series, 11 patients (ages, 20-63 years; mean, 41.9 ± 14.9 years, 2 women) with tumors located in or adjacent to the motor cortex were evaluated for surgery. fMRI and nTMS were applied for preoperative assessment of the extent of tumor resection. A 3-dimensional anatomic data set with superimposed fMRI data was integrated in the eXimia Navigated Brain Stimulation station for ensuing motor cortex mapping by nTMS. Responses from nTMS were evaluated by electromyographic response. During surgery, the coordinates of each DCS site were unambiguously defined and integrated into neuronavigation. A post hoc comparison of the coordinates of nTMS, fMRI, and DCS was performed. RESULTS: Distances from nTMS to DCS (10.5 ± 5.67 mm) were significantly smaller than those from fMRI to DCS (15.0 ± 7.6 mm). CONCLUSION: nTMS anticipates information usually only enabled by DCS and therefore allows surgical planning in eloquent cortex surgery.

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Limitation of Intraoperative Transcranial Electrical Stimulation-Motor Evoked Potential Monitoring During Brain Tumor Resection Adjacent to the Primary Motor Cortex

Annals of Rehabilitation Medicine ◽

10.5535/arm.2018.42.5.767 ◽

2018 ◽

Vol 42 (5) ◽

pp. 767-772

Author(s):

Hui Jae Do ◽

Han Gil Seo ◽

Byung-Mo Oh ◽

Chul-Kee Park ◽

Jin Wook Kim ◽

...

Keyword(s):

Electrical Stimulation ◽

Brain Tumor ◽

Motor Cortex ◽

Evoked Potential ◽

Primary Motor Cortex ◽

Tumor Resection ◽

Motor Evoked Potential ◽

Transcranial Electrical Stimulation ◽

Brain Tumor Resection ◽

Evoked Potential Monitoring

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Associations between clinical outcome and tractography based on navigated transcranial magnetic stimulation in patients with language-eloquent brain lesions

Journal of Neurosurgery ◽

10.3171/2018.12.jns182988 ◽

2020 ◽

Vol 132 (4) ◽

pp. 1033-1042 ◽

Cited By ~ 3

Author(s):

Nico Sollmann ◽

Alessia Fratini ◽

Haosu Zhang ◽

Claus Zimmer ◽

Bernhard Meyer ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Brain Tumors ◽

Risk Stratification ◽

Magnetic Stimulation ◽

Diffusion Tensor ◽

Tumor Resection ◽

Navigated Transcranial Magnetic Stimulation ◽

Language Mapping ◽

Significant Difference ◽

Related Pathway

OBJECTIVENavigated transcranial magnetic stimulation (nTMS) in combination with diffusion tensor imaging fiber tracking (DTI FT) is increasingly used to locate subcortical language-related pathways. The aim of this study was to establish nTMS-based DTI FT for preoperative risk stratification by evaluating associations between lesion-to-tract distances (LTDs) and aphasia and by determining a cut-off LTD value to prevent surgery-related permanent aphasia.METHODSFifty patients with left-hemispheric, language-eloquent brain tumors underwent preoperative nTMS language mapping and nTMS-based DTI FT, followed by tumor resection. nTMS-based DTI FT was performed with a predefined fractional anisotropy (FA) of 0.10, 0.15, 50% of the individual FA threshold (FAT), and 75% FAT (minimum fiber length [FL]: 100 mm). The arcuate fascicle (AF), superior longitudinal fascicle (SLF), inferior longitudinal fascicle (ILF), uncinate fascicle (UC), and frontooccipital fascicle (FoF) were identified in nTMS-based tractography, and minimum LTDs were measured between the lesion and the AF and between the lesion and the closest other subcortical language-related pathway (SLF, ILF, UC, or FoF). LTDs were then associated with the level of aphasia (no/transient or permanent surgery-related aphasia, according to follow-up examinations).RESULTSA significant difference in LTDs was observed between patients with no or only surgery-related transient impairment and those who developed surgery-related permanent aphasia with regard to the AF (FA = 0.10, p = 0.0321; FA = 0.15, p = 0.0143; FA = 50% FAT, p = 0.0106) as well as the closest other subcortical language-related pathway (FA = 0.10, p = 0.0182; FA = 0.15, p = 0.0200; FA = 50% FAT, p = 0.0077). Patients with surgery-related permanent aphasia showed the lowest LTDs in relation to these tracts. Thus, LTDs of ≥ 8 mm (AF) and ≥ 11 mm (SLF, ILF, UC, or FoF) were determined as cut-off values for surgery-related permanent aphasia.CONCLUSIONSnTMS-based DTI FT of subcortical language-related pathways seems suitable for risk stratification and prediction in patients suffering from language-eloquent brain tumors. Thus, the current role of nTMS-based DTI FT might be expanded, going beyond the level of being a mere tool for surgical planning and resection guidance.

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The effect of transcranial magnetic stimulation on the excitability of the motor neuron pools of the muscles of the lower extremities

10.34014/mpphe.2021-8-11 ◽

2021 ◽

Author(s):

S.S. Ananiev ◽

D.A. Pavlov ◽

R.N. Yakupov ◽

V.A. Golodnova ◽

M.V. Balykin

Keyword(s):

Spinal Cord ◽

Electrical Stimulation ◽

Transcranial Magnetic Stimulation ◽

Motor Cortex ◽

Magnetic Stimulation ◽

Primary Motor Cortex ◽

Lower Extremities ◽

Transcutaneous Electrical Stimulation ◽

Stimulation Of

The study was conducted on 22 healthy men aged 18-23 years. The primary motor cortex innervating the lower limb was stimulated with transcranial magnetic stimulation. Using transcutaneous electrical stimulation of the spinal cord, evoked motor responses of the muscles of the lower extremities were initiated when electrodes were applied cutaneous between the spinous processes in the Th11-Th12 projection. Research protocol: Determination of the thresholds of BMO of the muscles of the lower extremities during TESCS; determination of the BMO threshold of the TA muscle in TMS; determination of the thresholds of the BMO of the muscles of the lower extremities during TESCS against the background of 80% and 90% TMS. It was found that magnetic stimulation of the motor cortex of the brain leads to an increase in the excitability of the neural structures of the lumbar thickening of the spinal cord and an improvement in neuromuscular interactions. Key words: transcranial magnetic stimulation, transcutaneous electrical stimulation of the spinal cord, neural networks, excitability, neuromuscular interactions.

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