Regularised patient-specific stopping power calibration for proton therapy planning based on proton radiographic images.

Regularised patient-specific stopping power calibration for proton therapy planning based on proton radiographic images.
Phys Med Biol. 2019 Feb 01;:
Authors: Krah N, Patera V, Rit S, Schiavi A, Rinaldi I
Abstract
Proton transmission imaging has been proposed and investigated as imaging modality complementary to X-ray based techniques in proton beam therapy. In particular, it addresses the issue of range uncertainties due to the conversion of an X-ray patient computed tomography (CT) image expressed in Hounsfield Units (HU) to relative stopping power (RSP) needed as input to the treatment planning system. One approach to exploit a single proton radiographic projection is to perform a patient-specific calibration of the CT to RSP conversion curve by optimising the match between a measured and a numerically integrated proton radiography. 
 
 In this work, we develop the mathematical tools needed to perform such an optimisation in an efficient and robust way. Our main focus lies on set-ups which combine pencil beam scanning with a range telescope detector, although most of our methods can be employed in combination with other set-ups as well. Proton radiographies are simulated in Monte Carlo using an idealised detector and applying the same data processing chain used with experimental data. This approach allows us to have a ground truth CT-RSP curve to compare the optimisation results with. 
 
 Our result...

Source: Physics in Medicine and Biology - February 1, 2019 Category: Physics Authors: Krah N, Patera V, Rit S, Schiavi A, Rinaldi I Tags: Phys Med Biol Source Type: research