Somatosensory Evoked Potential Monitoring in Tumor and Brainstem Surgery

  • A. Witzmann
  • H. Beran
  • A. Huber
  • J. Fischer
Conference paper


This chapter describes general observations made and conclusions drawn regarding the prognostic value of intraoperative SSEP monitoring during tumor and brainstem surgery. Detailed analysis of the results of monitoring and neurological status evaluations of 97 patients suffering from tumors (cerebral hemisphere: N = 45; midline: N = 13; posterior fossa: N = 21; base of the skull: N = 6), or from cerebellar hemorrhage and infarction (N = 4), or undergoing functional neurosurgical procedures in the posterior fossa (N = 8) revealed recovery of central conduction time (CCT) at the end of surgery to be the most important prognostic factor for postoperative neurological status. Patients whose neurological status was the same as preoperatively (N = 79) did not show any significant change in CCT at the end of surgery compared with the CCT patterns after anesthesia induction. Patients whose neurological status deteriorated postoperatively (N = 18) showed significant CCT prolongation or even loss of the N20 component at the end of the procedure. When patients were grouped according to whether they had undergone infratentorial surgery, hemisphere tumor removal, or midline tumor removal, to determine if there were differences in CCT that were related to differences in lesion locations, the results were similar. Changes in amplitude of the N20 component also had prognostic value, but such changes were less significant because they were very variable and thus standard deviations were large.


Median Nerve Posterior Tibial Nerve Brainstem Auditory Evoke Potential Median Nerve Stimulation Posterior Tibial Nerve Stimulation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Abrahamian HA, Allison T, Goff WR, Rosner BS (1963) Effects of thiopental on human cerebral somatic evoked response. Anesthesiology 24: 650–657PubMedCrossRefGoogle Scholar
  2. Branston NM, Symon L, Crockard HA, Pasztor E (1974) Relationship between the cortical evoked potential and local cortical blood flow following acute middle cerebral artery occlusion in the baboon. Exp Neurol 45: 195–208PubMedCrossRefGoogle Scholar
  3. Branston NM, Symon L, Crockard HA (1976) Recovery of the cortical evoked response following temporary middle cerebral artery occlusion in baboons: Relation to local blood flow and P02. Stroke 7: 151–157PubMedCrossRefGoogle Scholar
  4. Cedzich C, Schramm J, Mengedoht CF, Fahlbusch R (1988) Factors that limit the use of flash visual evoked potentials for surgical monitoring. Electroenceph Clin Neurophysiol 71: 142–145PubMedCrossRefGoogle Scholar
  5. Chiappa KH (1983) Evoked Potentials in Clinical Medicine. Raven Press, New YorkGoogle Scholar
  6. Clark DL, Rosner BS (1973) Neurophysiologic effects of general anesthetics. I. The electroencephalogram and sensory responses in man. Anesthesiology 38: 564–582PubMedCrossRefGoogle Scholar
  7. Coles JG, Taylor MJ, Pearce JM, Lowry NJ, Stewart DJ, Trusler GA, Wilhams WG (1984) Cerebral monitoring of somatosensory evoked potentials during profoundly hypothermic circulatory arrest. Circulation (Suppl 1 ) 70: 96–102Google Scholar
  8. Desmedt JE (ed) (1989) Neuromonitoring in Surgery. Elsevier, Amsterdam, The NetherlandsGoogle Scholar
  9. Desmedt JE, Bourguet M (1985) Color imaging of scalp topography of parietal and frontal components of somatosensory evoked potentials to stimulation of median or posterior tibial nerve in man. Electroenceph Clin Neurophysiol 62: 1–17PubMedGoogle Scholar
  10. Desmedt JE, Cheron G (1980) Central somatosensory conduction in man: Neural generators and interpeak latencies of the farfield components recorded from neck and right or left scalp and earlobes.Electroenceph Clin Neurophysiol 50: 382–403Google Scholar
  11. Desmedt JE, Nguyen TH (1984) Bit-mapped color imaging of the potential fields of propagated and segmental subcortical components of somatosensory evoked potentials in man. Electroenceph Clin Neurophysiol 58: 481–497PubMedCrossRefGoogle Scholar
  12. De Vleeschauwer P, Horsch S, Heinrichs W (1985) Intraoperatives Erkennen von irrever-siblen Hirnischämien mit somatosensiblen evozierten Potentialen. Vasa 14: 125–130PubMedGoogle Scholar
  13. Donchin E, Herning RI (1975) A stimulation study of the efficacy of stepwise discriminant analysis in the detection and comparison of event related potentials. Electroenceph Clin Neurophysiology 38: 51–68CrossRefGoogle Scholar
  14. Drummond JC, Todd MM, Hoi Sang U (1985) The effect of high dose sodium thiopental on brainstem auditory and median nerve somatosensory evoked responses in humans. Anesthesiology 63: 249–254PubMedCrossRefGoogle Scholar
  15. Fischer C (1989) Brainstem auditory evoked potential (BAEP) monitoring in posterior fossa surgery. In Desmedt JE (ed) Neuromonitoring in Surgery. Elsevier, Amsterdam, pp 191–207Google Scholar
  16. Gentiii F, Lougheed WM, Yamashiro K, Corrado C (1985) Monitoring of sensory evoked potentials during surgery of skull base tumors. Can J Neurol Sci 12: 336–340Google Scholar
  17. Grundy BL (1982) Monitoring of sensory evoked potentials during neurological operations: Methods and applications. Neurosurgery 11: 556–575PubMedCrossRefGoogle Scholar
  18. Grundy BL, Jannetta PJ, Procopio PT, Lina A, Boston JR, Doyle E (1982) Intraoperative monitoring of brainstem auditory evoked potentials. J Neurosurg 57: 674–681PubMedCrossRefGoogle Scholar
  19. Hacke W, Hündgen R, Zeumer H, Ferbert A, Buchner H (1985) Überwachung der therapeutischen neuroradiologischen Untersuchungs- und Therapieverfahren mittels evozierten Potentialen. Z EEG EMG 16: 93–100Google Scholar
  20. Hume AL, Cant BR (1978) Conduction time in central somatosensory pathways in man. Electroenceph Clin Neurophysiol 45: 361–375PubMedCrossRefGoogle Scholar
  21. Markarid ON, Dilley RS, Moorthy SS, Warren C (1984) Monitoring of somatosensory evoked responses during carotid endarterectomy. Arch Neurol 41: 375–378Google Scholar
  22. Mauguiére F, Desmedt JE, Courjon J (1983a) Astereognosis and dissociated loss of frontal or parietal components of somatosensory evoked potentials in hemispheric lesions. Brain 106: 271–311PubMedCrossRefGoogle Scholar
  23. Mauguiére F, Desmedt JE, Courjon J (1983b) Neural generators of N18 and P14 farfield somatosensory evoked potentials: Patients with lesions of thalamus or thalamorcortical radiations. Electroenceph Clin Neurophysiol 56: 283–292PubMedCrossRefGoogle Scholar
  24. Møller AR (1988) Evoked Potentials in Intraoperative Monitoring. Williams & Wilkins, Baltimore, MarylandGoogle Scholar
  25. Noel P, Desmedt JE (1975) Somatosensory cerebral evoked potentials after vascular lesions of the brainstem and diencephalon. Brain 98: 113–128PubMedCrossRefGoogle Scholar
  26. Obeso JA, Marti-Masso JF, Carrera N (1980) Somatosensory evoked potentials: Abnormalities with focal lesions remote from the primary sensorimotor area. Electroenceph Clin Neurophysiol 49: 59–65PubMedCrossRefGoogle Scholar
  27. Prior PF, Maynard DE (1986) Monitoring Cerebral Function. Elsevier Science Publishers, Amsterdam, The NetherlandsGoogle Scholar
  28. Raudzens PA, Shetter AG (1982) Intraoperative monitoring of brainstem auditory evoked potentials. J Neurosurg 57: 341–348PubMedCrossRefGoogle Scholar
  29. Reisecker F, Witzmann A (1984) Das somatosensorisch evozierte Potential unter Bedingungen der Allgemeinanästhesie. W Klin Wochenschr 96: 64–67Google Scholar
  30. Reisecker F, Witzmann A, Löffler W, Leblhuber F, Deisenhammer E, Valencak E (1986) Somatosensory evoked potentials in various groups of cerebrovascular ischemic disease. Electroenceph Clin Neurophysiol 65: 260–268PubMedCrossRefGoogle Scholar
  31. Rossini PM, Gigli GL, Marciani MG, Zarola F, Caramia M (1987) Non-invasive evaluation of input-output characteristics of sensorimotor cerebral area in healthy humans. Electroenceph Clin Neurophysiol 68: 88–100PubMedCrossRefGoogle Scholar
  32. Schramm J (1989) Intraoperative monitoring with evoked potentials in cerebrál vascular surgery and posterior fossa surgery. In Desmedt JE (ed) Neuromonitoring in Surgery. Elsevier, Amsterdam, pp 243–262Google Scholar
  33. Sutton LN, Frewen T, Marsh R, Jaggi J, Bruce DA (1982) The effect of deep barbiturate coma on multimodality evoked potentials. J Neurosurg 57: 178–185PubMedCrossRefGoogle Scholar
  34. Symon L, Hargadine J, Zawirski M, Branston N (1979) Central conduction time as an index of ischemia in subarachnoid haemorrhage. J Neurol Sci 44: 95–103PubMedCrossRefGoogle Scholar
  35. Vogel P, Vogel H (1982) Somatosensory cortical potentials evoked by stimulation of leg nerves: Analysis of normal values and variability: Diagnostic significance. J Neurol 228: 97–111PubMedCrossRefGoogle Scholar
  36. Weber E (1973) Non-parametric methods. In Delaunois AL (ed) Biostatistics in Pharmacology 2. Pergamon Press, Oxford, England, pp 907–911Google Scholar
  37. Witzmann A, Reisecker F (1989) Somatosensory and auditory evoked potentials in tumor removal and brainstem surgery. In Desmedt IE (ed) Neuromonitoring in Surgery. Elsevier, Amsterdam, pp 219–241Google Scholar
  38. Witzmann A, Reisecker F, Valencak E, Deisenhammer E (1985) Intraoperative monitoring of cerebral functions in posterior fossa and foramen magnum by means of somatosensory evoked potentials. Electroenceph Clin Neurophysiol 61: 525–526CrossRefGoogle Scholar
  39. Witzmann A, Beran H, Bohm-Jurkovic H, Reisecker F, Loffler W (1987) Intraoperative somatosensory evoked potentials and tumor data in supratentorial surgery: Relation to prognosis and immediate postoperative state. J Clin Monit 3: 334–335Google Scholar
  40. Witzmann A, Beran H, Bohm-Jurkovic H, Loffler W (1990) The prognostic value of somatosensory evoked potential monitoring and tumor data in supratentorial tumor removal. J Clin Monit 6: 75–84PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • A. Witzmann
    • 1
  • H. Beran
  • A. Huber
  • J. Fischer
  1. 1.Abteilung für NeurochirurgieWagner-Jauregg- KrankenhausLinzAustria

Personalised recommendations