The study of quantitative optical absorption imaging by using Monte Carlo simulation of combined photoacoustic tomography and ultrasound-modulated optical tomography

We demonstrate the feasibility of quantitative optical absorption imaging by using Monte Carlo simulation of combined photoacoustic tomography (PAT) and ultrasound-modulated optical tomography (UOT). Our simulation results show that the optical fluence on initial photoacoustic (PA) pressure waves can be accurately compensated for recovering exact optical absorption coefficients by using a fluence map acquired from UOT signals. Further, when the optical heterogeneities of a sample were varied, the recovered optical absorption coefficients from a target remained constant while PA amplitudes fluctuated. In practice, PAT and UOT systems can be potentially combined because both imaging systems can easily share light illumination and ultrasound application patterns.