Abstract
Motor evoked potentials (MEPs) evoked by transcranial electrical stimulation (TES) have become an important technique for monitoring spinal cord function intra-operatively, but can fail in some patients. A new technique of double-train stimulation is described. A multipulse transcranial electrical stimulus is preceded by a preconditioning pulse train that leads to larger MEP responses. An MEP monitoring system was adapted for double-train transcranial stimulation (DTS). MEP responses from 160 anterior tibial muscles obtained by double-train stimulation were analysed. All patients received propofol/remifentanil/O2/N2O anaesthesia. Fifty-two (83%) out of 63 single-train tibial MEPs with response amplitudes below 100 μV were magnified to over 100 μV, with an inter-train (inter-stimulus) interval ITI=10–35 ms. These 63 amplitudes were magnified by an overall logarithmic mean factor of 15.5. For 97 MEPs with amplitudes above 100 μV, the logarithmic mean facilitation factor was 2.4. It was concluded that double-train TES stimulation can markedly facilitate responses to a single stimulus train (STS). The facilitation appears to be most effective when the responses to STS would otherwise be small or absent. This preconditioning stimulation technique is therefore useful when an STS leads to responses that are too small for effective monitoring.
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References
Berardelli, A., Rona, S., Inghilleri, M., andManfredi, M. (1996): ‘Cortical inhibition in Parkinson's disease. A study with paired magnetic stimulation’,Brain,119, pp. 71–77
Burke, D., Bartley, K., Woodforth, I. J., Yakoubi, A., andStephen, J. P. (2000): ‘The effects of a volatile anaesthetic on the excitability of human corticospinal axons’,Brain,123, pp. 992–1000
Calancie, B., Harris, W., Brindle, G. F., Green, B. A., andLandy, H. J. (2001), ‘Threshold-level repetitive transcranial electrical stimulation for intraoperative monitoring of central motor conduction’,J. Neurosurg.,95, pp. 161–168
Cruccu, G., Inghilleri, M., Berardelli, A., Romaniello, A., andManfredi, M. (1997): ‘Cortical mechanisms mediating the inhibitory period after magnetic stimulation of the facial motor area’,Muscle Nerve,20, pp. 418–424
Curra, A., Modugno, N., Inghilleri, M., Manfredi, M., Hallett, M., andBerardelli, A. (2002): ‘Transcranial magnetic stimulation techniques in clinical investigation’,Neurology,59, pp. 1851–1859
De Haan, P., Kalkman, C. J., De Mol, B. A., Ubags, L. H., Veldman, D. J., andJacobs, M. J. (1997): ‘Efficacy of transcranial motor-evoked myogenic potentials to detect spinal cord ischemia during operations for thoracoabdominal aneurysms’,J. Thorac. Cardiovasc. Surg., 113, pp. 87–100
Deletis, V., Isgum, V., andAmassian, V. E. (2001): ‘Neurophysiological mechanisms underlying motor evoked potentials in anesthetized humans. Part 1. Recovery time of corticospinal tract direct waves elicited by pairs of transcranial electrical stimuli’,Clin. Neurophysiol.,112, pp. 438–444
Ferbert, A., Priori, A., Rothwell, J. C., Day, B. L., Colebatch, J. G., andMarsden, C. D. (1992): ‘Interhemispheric inhibition of the human motor cortex’,J. Physiol,453, pp. 525–546
Jones, S. J., Harrison, R., Koh, K. F., Mendoza, N., andCrockard, H. A. (1996): ‘Motor evoked potential monitoring during spinal surgery: Responses of distal limb muscles to transcranial cortical stimulation with pulse trains’,Electroencephalogr. Clin. Neurophysiol.,100, pp. 375–383
Kalkman, C. J., Ubags, L. H., Been, H. D., Swaan, A., andDrummond, J. C. (1995): ‘Improved amplitude of myogenic motor evoked responses after paired transcranial electrical stimulation during sufentanil/nitrous oxide anesthesia’,Anesthesiology,83, pp. 270–276
Kothbauer, K., Deletis, V., andEpstein, F. J. (1997): ‘Intraoperative spinal cord monitoring for intramedullary surgery: An essential adjunct [see comments]’,Pediatr. Neurosurg.,26, pp. 247–254
Kujirai, T., Caramia, M. D., Rothwell, J. C., Day, B. L., Thompson, P. D., Ferbert, A., Wroe, S., Asselman, P., andMarsden, C. D. (1993): ‘Corticocortical inhibition in human motor cortex’,J. Physiol,471, pp. 501–519
Langeloo, D. D., Journee, H. L., Polak, B., andDe Kleuver, M. (2001): ‘A new application of tce-mep: Spinal cord monitoring in patients with severe neuromuscular weakness undergoing corrective spine surgery’,J. Spinal Disord.,14, pp. 445–448
Rodi, Z., Deletis, V., Morota, N., andVodusek, D. B. (1996): ‘Motor evoked potentials during brain surgery’,Pflugers Arch.,431, pp. R291-R292
Rothwell, J., Burke, D., Hicks, R., Stephen, J., Woodforth, I., andCrawford, M. (1994): ‘Transcranial electrical stimulation of the motor cortex in man: Further evidence for the site of activation’,J. Physiol. Lond.,481, pp. 243–250
Salerno, A., andGeorgesco, M. (1996): ‘Interhemispheric facilitation and inhibition studied in man with double magnetic stimulation’,Electroencephal. Clin. Neurophysiol.,101, pp. 395–403
Salerno, A., andGeorgesco, M. (1999): ‘Evoked motor potentials obtained with double magnetic cortical stimulation: Techniques and interpretation’,Neurophysiol. Clin.,29, pp. 235–253
Schafer, M., Biesecker, J. C., Schulze-Bonhage, A., andFerbert, A. (1997): ‘Transcranial magnetic double stimulation: Influence of the intensity of the conditioning stimulus’,Electroencephal. Clin. Neurophysiol.,105, pp. 462–469
Ubags, L. H., Kalkman, C. J., andBeen, H. D. (1998): ‘Influence of isoflurane on myogenic motor evoked potentials to single and multiple transcranial stimuli during nitrous oxide/opioid anesthesia’,Neurosurgery,43, pp. 90–94
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Journée, H.L., Polak, H.E., de Kleuver, M. et al. Improved neuromonitoring during spinal surgery using double-train transcranial electrical stimulation. Med. Biol. Eng. Comput. 42, 110–113 (2004). https://doi.org/10.1007/BF02351019
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DOI: https://doi.org/10.1007/BF02351019