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Updated: Aug 15, 2025

Evaluation of Fluid Overload by Bioelectrical Impedance Vectorial Analysis
Published on: August 17, 2022
[Calculation and Comparison of the Resistance Index Based on Vector Velocities and Correction Method Studies]
Yingying Shen1, Yigang Du1, Yong Huang1
1Shenzhen Mindray Bio-Medical Electronics Co. Ltd., Shenzhen, 518047.
Abstract:
Resistance Index (RI) is one of the indicators for ultrasound evaluation of hemodynamic changes. The purpose of this study is to evaluate the reliability of V Flow, which is a new ultrasound examination, when calculating this index. Data were collected from six positions of the bilateral common carotid artery (CCA) at the beginning, middle, and end of 10 healthy volunteers. The result shows that the RI error between V Flow and PW is about 12%. After angle correction for PW results both the relative error and its variance is reduced. Based on V Flow, users can directly obtain the actual flow velocity without manually correcting the angle. In addition to RI, blood flow velocity angle at different times can be compared to more intuitively to understand the hemodynamic details.
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