TY - JOUR
T1 - Validity and repronducibility of electrical impedance tomography for measurement of calf blood flow in healthy subjects
AU - Vonk Noordegraaf, A.
AU - Kunst, P.W.A.
AU - Janse, A.
AU - Smulders, R.A.
AU - Heethaar, R.M.
AU - Postmus, P.E.
AU - Faes, T.J.C.
AU - de Vries, P.M.J.M.
PY - 1997/3/1
Y1 - 1997/3/1
N2 - The Sheffield electrical impedance tomography; (EIT) system produces images of changes in the distribution of resistivity within tissue. The paper reports on the application of electrical impedance tomography in monitoring volume changes in the limb during venous occlusion. The aim of the study is to assess the feasibility, reproducibility and validity of calf blood flow measurements by EIT. In 14 healthy volunteers calf blood flow is compared, as determined in a calf segment by strain-gauge plethysmography (SGP), with the impedance changes measured by EIT during rest and post-ischaemic hyperaemia. The measurements are repeated to assess reproducibility. The reproducibility for the EIT, assessed from the repeated measurements and expressed as a reproducibility coefficient, is 0.88 during rest and 0.89 during hyperaemia. The reproducibility coefficient for SGP data is 0.83 at rest and 0.67 during hyperaemia. Flow measurements, assessed by means of two methods, correlate well at rest (r = 0.89), but only moderately during hyperaemia (r = 0.51). The correlation coefficient for the pooled flow measurements is 0.98. It is concluded that EIT is a valid and reliable method for assessing blood flow in the limb. Possible applications of EIT in localising fluid changes are discussed
AB - The Sheffield electrical impedance tomography; (EIT) system produces images of changes in the distribution of resistivity within tissue. The paper reports on the application of electrical impedance tomography in monitoring volume changes in the limb during venous occlusion. The aim of the study is to assess the feasibility, reproducibility and validity of calf blood flow measurements by EIT. In 14 healthy volunteers calf blood flow is compared, as determined in a calf segment by strain-gauge plethysmography (SGP), with the impedance changes measured by EIT during rest and post-ischaemic hyperaemia. The measurements are repeated to assess reproducibility. The reproducibility for the EIT, assessed from the repeated measurements and expressed as a reproducibility coefficient, is 0.88 during rest and 0.89 during hyperaemia. The reproducibility coefficient for SGP data is 0.83 at rest and 0.67 during hyperaemia. Flow measurements, assessed by means of two methods, correlate well at rest (r = 0.89), but only moderately during hyperaemia (r = 0.51). The correlation coefficient for the pooled flow measurements is 0.98. It is concluded that EIT is a valid and reliable method for assessing blood flow in the limb. Possible applications of EIT in localising fluid changes are discussed
KW - Blood flow
KW - Electrical impedance
KW - Plethysmography
KW - Tomography
UR - http://www.scopus.com/inward/record.url?scp=0031105346&partnerID=8YFLogxK
U2 - https://doi.org/10.1007/BF02534139
DO - https://doi.org/10.1007/BF02534139
M3 - Article
C2 - 9136202
SN - 0140-0118
VL - 35
SP - 107
EP - 112
JO - Medical & Biological Engineering & Computing
JF - Medical & Biological Engineering & Computing
IS - 2
ER -