Multilayer modeling of reflectance pulse oximetry.

A multilayer tissue description was employed in Monte Carlo simulations of reflectance pulse oximetry to study the impact of assumptions made in previous studies employing homogeneous tissue models. Simulation results with a discrete layer of arterial pulsatility were similar to previous studies employing homogenous tissue models. However, the relationship of normalized pulse amplitude to emitter-detector spacing reiterates that spacing has a significant impact on pulse oximetry function. The effect of melanin content as a thin, superficial absorber was also simulated, with results supporting the general clinical observation that skin shade need not substantially compromise pulse oximeter accuracy.