Monte Carlo simulations and laser Doppler flow measurements with high penetration depth in biological tissuelike head phantoms.

Laser Doppler flow measurements on biological tissuelike phantoms have shown that penetration depths of 30 mm could be obtained, thus exceeding the penetration depth of commercial instruments for the measurement of skin perfusion by more than an order of magnitude. Monte Carlo simulations were performed and compared with measurement results obtained on a headlike tissue model to quantify the influence of perfusion of the scalp on the cortex perfusion results. We found Doppler frequency spectra to be independent of the mean scattering angle and could be fitted with a sum of Gaussian functions, using a simple analytical model.