Abstract
Purpose: Proton CT is widely recognised as a beneficial alternative to conventional X-ray CT for treatment planning in proton beam radiotherapy. A novel proton CT imaging system, based entirely on solid-state detector technology, is presented. Compared to conventional scintillator-based calorimeters, positional sensitive detectors allow for multiple protons to be tracked per read out cycle, leading to a potential reduction in proton CT scan time. Design and characterisation of its components are discussed. An early proton CT image obtained with a fully solid-state imaging system is shown and accuracy (as defined in Section IV) in Relative Stopping Power to water (RSP) quantified. Method: A solid-state imaging system for proton CT, based on silicon strip detectors, has been developed by the PRaVDA collaboration. The system comprises a tracking system that infers individual proton trajectories through an imaging phantom, and a Range Telescope (RT) which records the corresponding residual energy (range) for each proton. A back-projection-then-filtering algorithm is used for CT reconstruction of an experimentally acquired proton CT scan. Results: An initial experimental result for proton CT imaging with a fully solid-state system is shown for an imaging phantom, namely a 75 mm diameter PMMA sphere containing tissue substitute inserts, imaged with a passively-scattered 125 MeV beam. Accuracy in RSP is measured to be ⩽1.6% for all the inserts shown. Conclusions: A fully solid-state imaging system for proton CT has been shown capable of imaging a phantom with protons and successfully improving RSP accuracy. These promising results, together with system the capability to cope with high proton fluences (2×108 protons/s), suggests that this research platform could improve current standards in treatment planning for proton beam radiotherapy.
Original language | English |
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Pages (from-to) | 149-154 |
Number of pages | 6 |
Journal | Physica Medica |
Volume | 55 |
DOIs | |
Publication status | Published - Nov 2018 |
Bibliographical note
Funding Information:The authors wish to thank aSpect Systems GmbH and ISDI Limited for their support and development of the PRaVDA system. This work was supported by the Wellcome Trust Translation Award Scheme , grant number 098285 .
Publisher Copyright:
© 2018 The Authors
Keywords
- Proton CT Elsevier
- Proton therapy
- Solid state detectors
ASJC Scopus subject areas
- Biophysics
- Radiology Nuclear Medicine and imaging
- General Physics and Astronomy