Monte Carlo simulation of measuring capillary blood flow with diffused light correlation

Abstract

The velocity of capillary blood flow is an important parameter to diagnose some diseases. In this paper, a model was set up to non-invasively measure the capillary blood flow using diffusing temporal light auto-correlation. This method is independent of the direction of blood flow. The distance between the light source and the detector was discussed in order to obtain high SNR (signal to noise ratio). The influences of the Brownian motion and the random flow of scatterers on the auto-correlation of diffusing light were analyzed with Monte Carlo simulation. The simulation results show that the characteristic correlation time exponentially decays as the mean-squared velocity of capillary blood flow increases, which is useful for medical diagnosis.