Lyl. Mo et al., ULTRASOUND SCATTERING FROM BLOOD WITH HEMATOCRITS UP TO 100-PERCENT, IEEE transactions on biomedical engineering, 41(1), 1994, pp. 91-95
The backscattering coefficient of saline suspensions of porcine red bl
ood cells was measured for hematocrits up to about 90%. It was found t
hat the coefficient peaks at approximately 15%, but then, contrary to
what a simple ''gap theory'' might suggest, it decays smoothly to zero
, without showing another peak at high hematocrits. A one-dimensional
(1-D) slab scattering model, in which the number of slabs per unit Len
gth represents the hematocrit and whose thickness and acoustical prope
rties are similar to red cells/plasma, was also used to investigate th
e relation between the backscattered power and hematocrit. Monte-Carlo
simulations performed for randomized boundary conditions show a simil
ar relation to that of the 3-D system. The experimental data is compar
ed to the Percus-Yevick theory for the packing of hard spheres, and th
e simulated data is compared to the Percus-Yevick theory for infinite
slabs.