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71. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
9. Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

21.06. - 24.06.2020

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Incidence and linguistic quality of speech errors – a comparison of TMS to intraoperative direct cortex stimulation reveals low reliability

Häufigkeit und Verteilung der Fehlerqualitäten beim Sprachmapping – ein Vergleich zwischen direkter kortikaler Stimulation und rnTMS

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  • Katharina Faust - Charité – Universitätsmedizin Berlin, Neurochirurgie, Berlin, Deutschland; Charité – Universitätsmedizin Berlin, Berlin, Deutschland
  • Peter Vajkoczy - Charité – Universitätsmedizin Berlin, Neurochirurgie, Berlin, Deutschland
  • Max Münch - Charité – Universitätsmedizin Berlin, Neurochirurgie, Berlin, Deutschland
  • presenting/speaker Ina Bährend - Charité – Universitätsmedizin Berlin, Neurochirurgie, Berlin, Deutschland
  • Thomas Picht - Charité – Universitätsmedizin Berlin, Neurochirurgie, Berlin, Deutschland
  • Rabih Moshourab - Charité – Universitätsmedizin Berlin, Neurochirurgie, Berlin, Deutschland
  • Heike Schneider - Charité – Universitätsmedizin Berlin, Neurochirurgie, Berlin, Deutschland

Deutsche Gesellschaft für Neurochirurgie. 71. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), 9. Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie. sine loco [digital], 21.-24.06.2020. Düsseldorf: German Medical Science GMS Publishing House; 2020. DocP189

doi: 10.3205/20dgnc474, urn:nbn:de:0183-20dgnc4743

Published: June 26, 2020

© 2020 Faust et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at http://creativecommons.org/licenses/by/4.0/.

Outline

Text

Objective: Due to the inter-individual variance of functional language anatomy, risk prediction based merely on anatomical data is insufficient in language area related brain tumor surgery, implicating a necessity for direct cortical and subcortical mapping during awake surgeries. Reliable non-invasive preoperative methods for language localization hold the potential to reduce the necessity for awake procedures, and may improve patient counselling and surgical planning. Repetitive navigated transcranial magnetic stimulation (rnTMS) is an evolving tool for localizing language eloquent areas. The aim of our study was to investigate the reliability of rnTMS in locating cortical language sites.

Methods: Prospectively, 25 patients with brain tumors in speech-related areas were evaluated with preoperative navigated transcranial rnTMS (5Hz train of five, 105% RMT) and navigated direct cortical stimulation (DCS, 50Hz, 6-8mA, 200µs pulse width) during awake surgeries, employing a picture-naming task. Positive and negative stimulation spots within the craniotomy were documented in the same MRI data set. TMS and DCS language positive areas were compared with regards to their spatial overlap, their allocation into a cortical parcellation system and their linguistic qualities.

Results: There were 2.5-fold more positive language spots within the exposed area in rnTMS than in DCS. The comparison of positive rnTMS and DCS overlaps revealed a low sensitivity (36%) and a low positive predictive value (16%), yet a high specificity (90%) and a high negative predictive value (96%). Within the overlaps, there was no correlation in error quality. In DCS, 71% of language positive spots were located in the pars opercularis and pars triangularis of the frontal operculum and 27% within the supramarginal gyrus and dorsal portion of the superior temporal gyrus, while in rnTMS language positivity was distributed more evenly over a large number of gyri.

Conclusion: The current protocol of rnTMS for language was able to confine language negative sites with good dependability, yet was unable to allocate language positive spots. Further refinements of the technique are needed to establish rnTMS language mapping as a useful clinical tool.