Laser Doppler velocimetry in blood and multiply scattering fluids: theory.

A detailed theory of LDV in dense multiply scattering fluids such as blood has been developed. Using a Feynman diagram renormalization technique, we derived generalized transport equations for the Doppler spectral space irradiance in a moving medium. We developed a Monte Carlo algorithm for solution of these equations in realistic fiber LDV geometries. Numerical results indicate that hydrodynamic boundary layer effects on the performance of LDV systems could be substantially reduced by proper choice of fiber geometry and signal processing method. We give a theory of the sources of noise in LDV systems, which shows that such improvements are feasible.