Systematic errors in multi-frequency EIT.
Physiol Meas
; 21(1): 111-8, 2000 Feb.
Article
em En
| MEDLINE
| ID: mdl-10720006
ABSTRACT
Systematic errors have been measured with a multi-frequency data-collection system operating between 10.24 and 81.92 kHz. The errors were present even though a conventional background measurement on a uniform saline phantom had already been subtracted. Errors due to changes in transimpedance between the calibration and the tissue measurements, cable movement and electrode-skin contact impedance were simulated giving a total systematic error estimate equivalent to a 9% change in tissue conductivity. It was shown that more than 89% of the image was above the total error magnitude, indicating that most of the image revealed true changes in tissue conductivity. In three human subjects, the largest conductivity changes were in two regions, located posteriorly on either side of the midline, and were interpreted as due to the erector spinae muscles. These regions showed increases in conductivity of 73-104%. Identification of other anatomical features was difficult because of the poor spatial resolution of the images.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tomografia
/
Impedância Elétrica
Tipo de estudo:
Diagnostic_studies
/
Evaluation_studies
Limite:
Humans
Idioma:
En
Revista:
Physiol Meas
Assunto da revista:
BIOFISICA
/
ENGENHARIA BIOMEDICA
/
FISIOLOGIA
Ano de publicação:
2000
Tipo de documento:
Article
País de afiliação:
Reino Unido