In vivo measurement of attenuation coefficient of blood in a dorsal hand vein in a frequency range of 10–45 MHz: A preliminary study

Abstract

In this study, the attenuation coefficient of blood was measured in vivo in the frequency range of 10–45 MHz. A procedure to correct the distribution of sound pressure in the measurements was discussed. Further, in vivo measurements were applied on the dorsal hand vein of four healthy subjects at rest and during avascularization. As a preliminary result, less variation of the measured attenuation coefficients was achieved by the proposed method. The comparable results of the inclination of the attenuation coefficients were obtained at rest and during avascularization. Furthermore, the attenuation coefficients during avascularization were markedly higher than those at rest, reflecting the degree of red blood cell aggregation promoted by avascularization. This method may aid in the non-invasive evaluation of blood properties reflecting the degree of red blood cell aggregation.

Estimation of red blood cell aggregation size using power spectrum considering density of red blood cells in focal region

“…was determined from the power spectra obtained from 8.0 mm and 9.0 mm at 0.1 mm intervals. 35) The size of the microparticles was estimated by fitting the measured power spectrum corrected for the attenuation property difference proposed method, we compared the estimated sizes with those estimated by the reference scattering power spectra considering a single scatterer. 30) The same attenuation coefficient ( ) f p a was used for the correction in both the previous 30) and proposed methods.…”