Indicator dilution methods allow absolute fluid volume estimation; cardiac magnetic resonance (CMR) has been recently proposed to apply indicator dilution methods in a minimally-invasive manner.  In this study, we aim to compare bio-impedance spectroscopy (BIS) and CMR for the assessment of thoracic fluid status, and to determine their ability to detect fluid displacement induced by a leg compression procedure in healthy volunteers.  Each subject underwent a continuous TI-BIS measurement during the procedure, and repeated CMR-based indicator dilution measurements on a 1.5 T scanner at baseline, during compression, and after pressure release.  Intra-thoracic blood volume index (ITBI) derived from CMR, and extracellular fluid resistance (R E) from TI-BIS, were considered as thoracic fluid status measures.  Significant changes were observed in the considered thoracic fluid measures derived from BIS and CMR. 
CMR
In this study, we aim to compare bio-impedance spectroscopy (BIS) and CMR for the assessment of thoracic fluid status, and to determine their ability to detect fluid displacement induced by a leg compression procedure in healthy volunteers.  Each subject underwent a continuous TI-BIS measurement during the procedure, and repeated CMR-based indicator dilution measurements on a 1.5 T scanner at baseline, during compression, and after pressure release.  The Cole-Cole and the local density random walk models were used for parameter extraction from TI-BIS and indicator dilution measurements, respectively.  Intra-thoracic blood volume index (ITBI) derived from CMR, and extracellular fluid resistance (R E) from TI-BIS, were considered as thoracic fluid status measures.  Significant changes were observed in the considered thoracic fluid measures derived from BIS and CMR. 
BIS
Each subject underwent a continuous TI-BIS measurement during the procedure, and repeated CMR-based indicator dilution measurements on a 1.5 T scanner at baseline, during compression, and after pressure release.  The Cole-Cole and the local density random walk models were used for parameter extraction from TI-BIS and indicator dilution measurements, respectively.  Intra-thoracic blood volume index (ITBI) derived from CMR, and extracellular fluid resistance (R E) from TI-BIS, were considered as thoracic fluid status measures. 
TI-BIS
Indicator dilution methods allow absolute fluid volume estimation; cardiac magnetic resonance (CMR) has been recently proposed to apply indicator dilution methods in a minimally-invasive manner. 
indicator dilution methods
The Cole-Cole and the local density random walk models were used for parameter extraction from TI-BIS and indicator dilution measurements, respectively. 
local density random walk models