The Doppler signal converter accurately converted audio signals into real-time flow velocity, demonstrating high agreement with the standard HDI 5000 system in vivo (concordance correlation coefficient 0.992).
A novel, inexpensive Doppler signal converter allows real-time conversion of ultrasound audio signals into fluid flow velocity for physiological research.
Effect estimate: Concordance correlation coefficient 0.992 (95% CI 0.990-0.993)
p-value: p=<0.001
A Doppler signal converter has been developed to facilitate cardiovascular and exercise physiology research. This device directly converts audio signals from a clinical Doppler ultrasound imaging system into a real-time analog signal that accurately represents blood flow velocity and is easily recorded by any standard data acquisition system. This real-time flow velocity signal, when simultaneously recorded with other physiological signals of interest, permits the observation of transient flow response to experimental interventions in a manner not possible when using standard Doppler imaging devices. This converted flow velocity signal also permits a more robust and less subjective analysis of data in a fraction of the time required by previous analytic methods. This signal converter provides this capability inexpensively and requires no modification of either the imaging or data acquisition system.
Herr et al. (Fri,) conducted a other in Healthy volunteers (n=10). Doppler signal converter vs. HDI 5000 Doppler ultrasound system was evaluated on Concordance correlation coefficient of time-averaged mean (TAM) flow velocity in vivo (Concordance correlation coefficient 0.992, 95% CI 0.990-0.993, p=<0.001). The Doppler signal converter accurately converted audio signals into real-time flow velocity, demonstrating high agreement with the standard HDI 5000 system in vivo (concordance correlation coefficient 0.992).