Design Study on Photoacoustic Probe to Detect Prostate Cancer using 3D Monte Carlo Simulation and Finite Element Method

Purpose In this work, we propose an alternative photoacoustic probe based on transurethral laser illumination to a conventional transrectal photoacoustic imaging system suffering from a high optical absorption at a rectal wall and its surrounding tissues. Methods We validate improved performance of the proposed scheme using 3-dimensional prostate model and analytical calculations such as Monte Carlo simulation and finite element method (FEM). Monte Carlo simulation and FEM are used to find the absorption profiles of photons and the accompanying temperature elevation and pressure signal generation. Results It is found that light source inside the urethra and ultrasound transducer on the rectal wall is an optimal combination to produce a high amplitude in pressure signal and a high signal-to-noise ratio in the reconstructed image. Design study on light source geometry such as beam shape, beam size and gap distance between two light sources is also performed to improve an absorption efficiency at the prostate cancer. Conclusions Our study will be helpful in determining an optimized probe design of photoacoustic imaging system for advancing the detection of prostate cancer.