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61st Annual Meeting of the German Society of Neurosurgery (DGNC) as part of the Neurowoche 2010
Joint Meeting with the Brazilian Society of Neurosurgery on the 20 September 2010

German Society of Neurosurgery (DGNC)

21 - 25 September 2010, Mannheim

Intraoperative direct cortical stimulation in 103 supratentorial gliomas: a single-center experience

Meeting Abstract

  • Ehab Shiban - Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Deutschland
  • Sandro Krieg - Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Deutschland
  • Jens Gempt - Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Deutschland
  • D. Droese - Anaesthesiology, Klinikum rechts der Isar, Technische Universität München, Deutschland
  • Florian Ringel - Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Deutschland
  • Bernhard Meyer - Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Deutschland

Deutsche Gesellschaft für Neurochirurgie. 61. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC) im Rahmen der Neurowoche 2010. Mannheim, 21.-25.09.2010. Düsseldorf: German Medical Science GMS Publishing House; 2010. DocV1575

DOI: 10.3205/10dgnc050, URN: urn:nbn:de:0183-10dgnc0509

Published: September 16, 2010

© 2010 Shiban et al.
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Outline

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Objective: Resection of gliomas in the vicinity of the corticospinal tract remains a neurosurgical challenge but is feasible in association with electrophysiological monitoring. Our experience using direct cortical stimulation following SEP phase reversal for the resection of motor eloquent tumors is described.

Methods: Between 2006 and 2009 direct cortical stimulation and MEP monitoring was performed in 103 cases of supratentorial gliomas close to or in motor eloquent locations. MEPs were elicited by direct cortical stimulation after identification of the precentral gyrus by SEP phase reversal using grid electrodes. An anodal stimulation according to the “train of five technique” was used. Stimulation was repeated every 30sec, at critical surgical steps up to every 5sec. A reproducible decrease of MEP-amplitude of at least 50% was considered as significant. Clinical outcome was assessed immediately after surgery, at discharge and during regular outpatient follow-ups.

Results: MEP monitoring was successful in 97 cases (94%). New postoperative motor deficits occurred in 18 (17%). It was transient in 15 (15%) and permanent in 3 (3%). Out of 74 cases with stable MEPs, 8 developed a new transient paresis. However, all of these patients had tumors resected from the supplementary motor area and motor deficits rapidly recovered. Out of 19 cases with reversible MEP changes 7 developed a transient paresis, none were permanent. All 3 cases with irreversible MEP changes developed permanent new motor deficits. In 4 cases (6%) MEP recording was not possible - preoperative hemiplegia in 2, 2 cases of unexplained failure. Due to alterations in MEP further resection was terminated in 16 cases. Of those, 4 patients had a new paresis (all transient). Unexpected tumor residual was found in 1 case, tumor residuals as anticipated were seen in 10 cases.

Conclusions: Cortical stimulation and MEP monitoring provides a reliable monitoring of the corticospinal tract and can influence the course of resection. In our series we found no false negative MEP results except for patients with tumors in the supplementary motor cortex resulting in SMA syndromes with rapid recovery of motor deficits. Reversible MEP changes were associated with reversible deficits if at all. Therefore, MEP monitoring has to be regarded as gold standard for the surgical treatment of lesions close to or in motor eloquent areas.