A Deterministic Adjoint-Based Semi-Analytical Algorithm for Fast Response Change Computations in Proton Therapy

In this paper we propose a solution to the need for fast particle transport algorithm in Online Adaptive Proton Therapy capable of cheaply, but accurately computing changes patient dose metrics as result system parameters. We obtain proton phase-space density through product numerical one-dimensional Fokker-Planck equation and analytical Fermi-Eyges equation. Moreover, corresponding adjoint was derived solved flux. The together with flux metric (chosen energy deposited by beam variable region interest) allowed assessing accuracy our different perturbation ranges parameters regions interest. achieved negligible errors (1.1×10−6% 3.6×10−3%) small Hounsfield unit (HU) (–40 HU 40 HU) moderate (3% 17%) – line well-known limitation approaches large (–400 400 case most clinical interest where surrounds Bragg peak. Given these results coupled capability further improving timing performance it can be concluded that presents viable specific purpose Therapy.