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Biomag 96 pp 1022-1025 | Cite as

Normalized N100m Latency of the Auditory Evoked Fields After Surgical Removal of Temporal Lobe Gliomas

  • A. Kanno
  • N. Nakasato
  • S. Ohtomo
  • K. Seki
  • T. Kawamura
  • S. Fujita
  • T. Kumabe
  • T. Kayama
  • T. Yoshimoto
Conference paper

Abstract

Auditory evoked potentials have been measured in patients with several temporal lobe diseases. The N100 responses disappear in patients with lesions on bilateral superior temporal gyrus[1]. However, separation of a unilateral abnormality in evoked potentials, is difficult due to the spearing effect by tissue layers with inhomogeneous electric conductivities. Activity on the normal hemisphere may interfere with abnormal activity on the diseased hemisphere. Magnetoencephalography (MEG) is known to be less influenced by the inhomogeneous head conductivity. We have found that the whole head MEG is especially suitable to identify differences in bilateral cerebral function [2–4].

Keywords

Temporal Lobe Cystic Tumor Left Temporal Lobe Ipsilateral Response Dipole Position 
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.

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References

  1. [1]
    Woods, D.L., Clayworth, C.C., Knight, R.T., Simpson, G.V., and Naeser, M.A. Generators of middle and long-latency auditory evoked potentials: implications from studies of patients with bitemporal lesions. Electroencephalography and Clinical Neurophysiology, 1987, 68: 132–148.CrossRefGoogle Scholar
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    Kanno, A., Nakasato, N., Fujita, S., Seki, K., Kawamura, T., Ohtomo, S., Fujiwara, S., and Yoshimoto, T. Right hemispheric dominance in the auditory evoked magnetic fields for pure-tone stimuli. Electroencephalography and Clinical Neurophysiology, in press.Google Scholar
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Copyright information

© Springer Science+Business Media New York 2000

Authors and Affiliations

  • A. Kanno
    • 1
  • N. Nakasato
    • 1
    • 2
  • S. Ohtomo
    • 2
  • K. Seki
    • 2
  • T. Kawamura
    • 2
  • S. Fujita
    • 4
  • T. Kumabe
    • 2
  • T. Kayama
    • 3
  • T. Yoshimoto
    • 2
  1. 1.MEG LaboratoryKohnan HospitalSendaiJapan
  2. 2.Department of NeurosurgeryTohoku University School of MedicineSendaiJapan
  3. 3.Department of NeurosurgeryYamagata University School of MedicineYamagataJapan
  4. 4.Osaka Gas Co. Ltd.R&D CenterOsakaJapan

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