Optimisation of the design of SOI microdosimeters for hadron therapy quality assurance.

Optimisation of the design of SOI microdosimeters for hadron therapy quality assurance.
Phys Med Biol. 2018 Oct 24;63(21):215007
Authors: Bolst D, Guatelli S, Tran LT, Rosenfeld AB
Abstract
Silicon-on-insulator (SOI) microdosimeters offer a promising method for routine quality assurance (QA) for hadron therapy due to their ease of operation and high spatial resolution. However, one complication which has been shown previously is that the traditional use of the mean chord length, [Formula: see text], calculated using Cauchy's formula, for SOI devices in clinical carbon ion fields is not appropriate due to the strong directionality of the radiation field. In a previous study, we demonstrated that the mean path length, [Formula: see text], which is the mean path of charged particles in the sensitive volume (SV), is a more appropriate method to obtain microdosimetric quantities and biological relevant values, namely the relative biological effectiveness (RBE) by means of the microdosimetric kinetic model. The previous work, which was limited to mono-energetic [Formula: see text] ion beams typical of heavy ion therapy (HIT), is extended here to investigate the [Formula: see text] in a pristine proton beam as well as for spread out Bragg peaks (SOBP) for both proton and carbon ion clinical beams. In addition, the angular dependence of the SOI device for a number of different SV designs is also investigated to quantify the effects which the...

Source: Physics in Medicine and Biology - October 24, 2018 Category: Physics Authors: Bolst D, Guatelli S, Tran LT, Rosenfeld AB Tags: Phys Med Biol Source Type: research