Dosimetric characteristics of the University of Washington clinical neutron therapy system.

Dosimetric characteristics of the University of Washington clinical neutron therapy system. Phys Med Biol. 2018 Apr 11;: Authors: Moffitt GB, Stewart RD, Sandison GA, Goorley JT, Argento DC, Jevremovic T, Emery R, Wootton LS, Parvathaneni U, Laramore GE Abstract The University of Washington (UW) Clinical Neutron Therapy System (CNTS), which generates high linear energy transfer (LET) fast neutrons through interactions of 50.5 MeV protons incident on a Be target, has depth-dose characteristics similar to 6 MV x-rays. In contrast to the fixed beam angles and primitive blocking used in early clinical trials of neutron therapy, the CNTS has a gantry with a full 360<sup>○</sup> of rotation, internal wedges, and a multi-leaf collimator (MLC). Since October of 1984, over 3,178 patients have received conformal neutron therapy treatments using the UW CNTS. In this work, the physical and dosimetric characteristics of the CNTS are documented through comparisons of measurements and Monte Carlo simulations. A high resolution computed tomography scan of the model 17 ionization chamber (IC-17) has also been used to improve the accuracy of simulations of the absolute calibration geometry. The response of the IC-17 approximates well the kinetic energy released per unit mass (KERMA) in water for neutrons and photons for energies from a few tens of keV up to about 20 MeV. Above 20 MeV, the simulated model 17 ion chamber re...
Source: Physics in Medicine and Biology - Category: Physics Authors: Tags: Phys Med Biol Source Type: research