Advertisement

Motor Evoked Potentials: Issues in Safety and Operative Monitoring

  • W. J. Levy
  • J. Oro
  • M. Traad
Conference paper

Abstract

The monitoring of the motor system is an important goal for spinal cord evaluation. Ideally we need a safe procedure, easily used, reliable, and able to indicate problems with the upper or lower motor neuron pathways. Until a few years ago little was available in such a direction. However, the advent of both spinal cord stimulation and transcranial motor pathway stimulation has offered the opportunity to develop such testing. A particularly useful type of transcranial stimulation in the awake patient is the magnetic stimulator, first described in 1985 by Dr. Anthony Barker. This stimulator was initially limited by the large surface area of brain which it stimulated, and by the fact that it was just powerful enough to stimulate awake patients. Therefore it was often not reliable on an anesthetized patient with a higher stimulus threshold. The technology of these devices is evolving rapidly, and more powerful stimulators are being tested by Novametrix and Cadwell Labs, as well as some other groups. The one which has been initially evaluated for the operating room is the Cadwell MES-10. This can stimulate patients in the operating room under some conditions.

Keywords

Motor Cortex Motor Unit Magnetic Stimulation Motor Evoke Potential Spinal Cord 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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Agnew, McCreery (1987) Safety in transcranial stimulation. Neurosurgery 20 (1): 100–109CrossRefGoogle Scholar
  2. 2.
    Barker AT, Jalinous R, Freeston IL (1985) Non-invasive magnetic stimulation of human motor cortex. Lancet i: 1106–1007PubMedCrossRefGoogle Scholar
  3. 3.
    Bridge SL, Delaney RC (1989) Transcranial magnetic stimulation: An Assessment of Cognitive and other cerebral effects. Neurology 39: 417–419, 1989Google Scholar
  4. 4.
    Brown Rh, Nash CL, Lorig RA, Schatzinger LA (1977) Spinal cord monitoring during operative treatment of the spine. Clin Orthop 126: 100–105PubMedGoogle Scholar
  5. 5.
    Edmunds HL, Paloheimo MPJ, Backman M, Johnson JR, Holt RT, Schields CB (1989) Transcranial magnetic motor evoked potentials (tcMMEP) for functional monitoring of motor pathways during scholiosis surgery. Spine 14: 683–686CrossRefGoogle Scholar
  6. 6.
    Levy WJ (1987) SEP vs MEP debate: the monitoring of motor pathways. Clin Neurosurg 34: 239–260Google Scholar
  7. 7.
    Levy WJ, McCaffrey M, York DH, Tanzer F (1984) Motor evoked potentials from transcranial stimulation of the motor cortex in humans. Neurosurgery 15: 214–227PubMedCrossRefGoogle Scholar
  8. 8.
    Levy WJ, McCaffrey M, York DH, Tanzer F (1984) Motor evoked potentials from transcranial stimulation of the motor cortex in cats. Neurosurgery 15: 287–302PubMedCrossRefGoogle Scholar
  9. 9.
    Levy WJ, Oro J, Tucker D (1989) Safety studies of electrical and magnetic stimulation for the production of motor evoked potentials. In: Magnetic stimulation in clinical neurophysiology. Butterworth, LondonGoogle Scholar
  10. 10.
    Moller AR (1987) Electrophysiological monitoring of cranial nerves in operations in the skull base. In: Sekar LN, Schramm V (eds) Tumors of the cranial base: diagnosis and treatment. Futura, Mt. KiscoGoogle Scholar
  11. 11.
    Moller AR, Jannetta PJ (1984) Preservation of facial nerve function during removal of acoustic neuromas. Use of monopolar constantp-voltage stimulation adn EMG. J Neurosurg 61: 757–760PubMedCrossRefGoogle Scholar
  12. 12.
    Moller AR, Jannetta PJ (1985) Monitoring of facial nerve function during removal of acoustic tumor. Am J Otol [November Suppl]: 27–29Google Scholar
  13. 13.
    Prass R, Luders H (1986) Acoustic (loudspeaker) facial electromyographic monitoring Part 1. Neurosurgery 19: 392–400PubMedCrossRefGoogle Scholar
  14. 14.
    Raudzens PA (1982) Intraoperative monitoring of evoked potentials. In: BodisWollner I (ed) Evoked potentials. New York Academy of Sciences, New York, pp 308–325Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • W. J. Levy
    • 1
    • 2
  • J. Oro
  • M. Traad
  1. 1.University of PittsburghPittsburghUSA
  2. 2.University of MissouriColumbiaUSA

Personalised recommendations