Iy. Kuo et Kk. Shung, HIGH-FREQUENCY ULTRASONIC BACKSCATTER FROM ERYTHROCYTE SUSPENSION, IEEE transactions on biomedical engineering, 41(1), 1994, pp. 29-34
Previous studies have shown that ultrasonic backscattering from red bl
ood cells suspended in saline is proportional to the fourth power of f
requency for frequencies below 15 MHz, as predicted by Rayleigh scatte
ring theory. Recently, we have extended the measurements up to 30 MHz,
because scattering of ultrasound by red blood cells may no longer be
negligible at these frequencies and can affect, to a great degree, the
operation of intravascular imaging devices. The experimental results
show that the fourth power dependence on frequency of the backscatteri
ng coefficient for porcine erythrocytes suspended in saline solution a
ppears to be valid up to 30 MHz. To confirm this, backscattering cross
-section of porcine red cells was computed as a function of frequency
using the T-matrix method. Since at higher frequencies the shape of th
e scatterers may also play a significant role, its effect was investig
ated by treating the red cell as a sphere, a disc, and a biconcave dis
c of the same volume. Good agreement was obtained between the experime
ntal and theoretical results.