title: Stochastic ray tracing for simulation of high intensity focal ultrasound therapy.
abstract: An algorithm is presented for rapid simulation of high-intensity focused ultrasound (HIFU) fields. Essentially, the method combines ray tracing with Monte Carlo integration to evaluate the Rayleigh-Sommerfeld integral. A large number of computational particles, phonons, are distributed among the elements of a phase-array transducer. The phonons are emitted into random directions and are propagated along trajectories computed with the ray tracing method. As the simulation progresses, an improving stochastic estimate of the acoustic field is obtained. The method can adapt to complicated geometries, and it is well suited to parallelization. The method is verified against reference simulations and pressure measurements from an ex vivo porcine thoracic tissue sample. Results are presented for acceleration with graphics processing units (GPUs). The method is expected to serve in applications, where flexibility and rapid computation time are crucial, in particular clinical HIFU treatment planning.
authors.affiliation: Philips Healthcare, Philips Medical Systems MR Finland, P.O. Box 185, Vantaa, FI-01511, Finland.
authors.forename: Julius
authors.initials: J
authors.lastname: Koskela
authors.affiliation: Philips Healthcare, Philips Medical Systems MR Finland, P.O. Box 185, Vantaa, FI-01511, Finland.
authors.forename: Erkki
authors.initials: E
authors.lastname: Vahala
authors.affiliation: Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, Utrecht 3584CX, The Netherlands.
authors.forename: Martijn
authors.initials: M
authors.lastname: de Greef
authors.affiliation: Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, Utrecht 3584CX, The Netherlands.
authors.forename: Luc P
authors.initials: LP
authors.lastname: Lafitte
authors.affiliation: Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, Utrecht 3584CX, The Netherlands.
authors.forename: Mario
authors.initials: M
authors.lastname: Ries