Effects of electrodes length and insulation for transcranial electric stimulation.
Corkscrew electrode
Insulation
Transcranial electric stimulation
Transcranial motor evoked potential
Journal
Surgical neurology international
ISSN: 2229-5097
Titre abrégé: Surg Neurol Int
Pays: United States
ID NLM: 101535836
Informations de publication
Date de publication:
2019
2019
Historique:
received:
17
08
2018
accepted:
02
05
2019
entrez:
19
9
2019
pubmed:
19
9
2019
medline:
19
9
2019
Statut:
epublish
Résumé
The aim of this study is to investigate the effects of length and insulation of the corkscrew electrodes for transcranial motor evoked potential (tMEP) monitoring. We used the finite element method to visualize the electric field in the brain, which was generated by electrodes of different lengths (4, 7, and 12 mm). Two types of head models were generated: A model that included a subcutaneous fat layer and another without a fat layer. Two insulated needle types of conductive tip (5 and 2 mm) were studied. The stimulation threshold levels of hand tMEP were measured in a clinical setting to compare normal corkscrew and insulated 7-mm depth corkscrew. The electric field in the brain depended on the electrode depths in the no fat layer model. The deeper the electrodes reached, the stronger the electric fields generated. Electrode insulation made a difference in the fat layer models. The threshold level recordings of tMEP revealed that the 7-mm insulated electrodes showed a lower threshold than the normal electrodes by one-side replacement in each patient: 33.6 ± 9.6 mA and 36.3 ± 11.0 mA ( The electrodes depth reached enough to skull is considered to be efficient. Insulation of the electrodes with a conductive tip is efficient when there is subcutaneous fat layer.
Sections du résumé
BACKGROUND
BACKGROUND
The aim of this study is to investigate the effects of length and insulation of the corkscrew electrodes for transcranial motor evoked potential (tMEP) monitoring.
METHODS
METHODS
We used the finite element method to visualize the electric field in the brain, which was generated by electrodes of different lengths (4, 7, and 12 mm). Two types of head models were generated: A model that included a subcutaneous fat layer and another without a fat layer. Two insulated needle types of conductive tip (5 and 2 mm) were studied. The stimulation threshold levels of hand tMEP were measured in a clinical setting to compare normal corkscrew and insulated 7-mm depth corkscrew.
RESULTS
RESULTS
The electric field in the brain depended on the electrode depths in the no fat layer model. The deeper the electrodes reached, the stronger the electric fields generated. Electrode insulation made a difference in the fat layer models. The threshold level recordings of tMEP revealed that the 7-mm insulated electrodes showed a lower threshold than the normal electrodes by one-side replacement in each patient: 33.6 ± 9.6 mA and 36.3 ± 11.0 mA (
CONCLUSIONS
CONCLUSIONS
The electrodes depth reached enough to skull is considered to be efficient. Insulation of the electrodes with a conductive tip is efficient when there is subcutaneous fat layer.
Identifiants
pubmed: 31528449
doi: 10.25259/SNI-133-2019
pii: SNI-10-111
pmc: PMC6744809
doi:
Types de publication
Journal Article
Langues
eng
Pagination
111Déclaration de conflit d'intérêts
There are no conflicts of interest.
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