APPLICATION OF A GTEM CELL TO DETERMINE RF INDUCED CURRENTS IN ELECTRODES OF MEDICAL IMPLANTS - An Alternative to Measurements in MRI Birdcages

Karin Mörtlbauer, Daniel Zemann, Erwin Hochmair

Abstract

RF induced currents in elongated electrodes of medical implants can cause hazardous tissue heating during MRI scans. In this paper we introduce an experimental setup to investigate the influence of the geometrical electrode design on the magnitude of the RF induced current. A Vector Network Analyser (VNA) was connected to a Gigahertz Transverse Electromagnetic (GTEM) cell containing the electrode under test. The forward power gain (S21 scattering parameter) was measured by the VNA, whereof the magnitude of the current at the electrode tip could be derived. Furthermore, calculations via transmission line theory were done to describe the present mechanism of current induction. These calculations show good agreement with the results of the performed measurements.

References

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Paper Citation


in Harvard Style

Mörtlbauer K., Zemann D. and Hochmair E. (2012). APPLICATION OF A GTEM CELL TO DETERMINE RF INDUCED CURRENTS IN ELECTRODES OF MEDICAL IMPLANTS - An Alternative to Measurements in MRI Birdcages . In Proceedings of the International Conference on Biomedical Electronics and Devices - Volume 1: BIODEVICES, (BIOSTEC 2012) ISBN 978-989-8425-91-1, pages 315-318. DOI: 10.5220/0003763103150318


in Bibtex Style

@conference{biodevices12,
author={Karin Mörtlbauer and Daniel Zemann and Erwin Hochmair},
title={APPLICATION OF A GTEM CELL TO DETERMINE RF INDUCED CURRENTS IN ELECTRODES OF MEDICAL IMPLANTS - An Alternative to Measurements in MRI Birdcages},
booktitle={Proceedings of the International Conference on Biomedical Electronics and Devices - Volume 1: BIODEVICES, (BIOSTEC 2012)},
year={2012},
pages={315-318},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0003763103150318},
isbn={978-989-8425-91-1},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Conference on Biomedical Electronics and Devices - Volume 1: BIODEVICES, (BIOSTEC 2012)
TI - APPLICATION OF A GTEM CELL TO DETERMINE RF INDUCED CURRENTS IN ELECTRODES OF MEDICAL IMPLANTS - An Alternative to Measurements in MRI Birdcages
SN - 978-989-8425-91-1
AU - Mörtlbauer K.
AU - Zemann D.
AU - Hochmair E.
PY - 2012
SP - 315
EP - 318
DO - 10.5220/0003763103150318