A collaboration led by Enrique Nácher, from the Institute of Corpuscular Physics (IFIC), has developed the first fully Spanish proton tomography scanner. The device reuses prototypes from other nuclear physics projects and has been tested at a proton therapy centre in Poland. The first results of this project, developed in collaboration with the Institute of Structure of Matter (IEM-CSIC) and the Complutense University of Madrid (UCM), have been published in The European Physical Journal Plus.
Proton therapy is an advanced form of cancer treatment that uses protons. In recent years, it has gained popularity due to its advantages over conventional radiotherapy, as these particles deposit almost all their energy in tumour cells with minimal effect on healthy tissue. However, accurate treatment planning requires precise medical imaging of the patient.
Nowadays, these images are obtained with X-rays through computed tomography scans (CT scans). However, the subsequent treatment is performed with proton beams, not X-rays, which introduces uncertainties in treatment planning and dose calculation.
The new scanner allows imaging directly with protons and is the first device of its kind developed in Spain. "Although it is currently a preclinical scanner that has obtained images of small phantoms, the results are promising and have demonstrated the feasibility of the concept", says Enrique Nácher, CSIC scientist at IFIC and director of this project.
The research team combined a set of tracking detectors and a high-energy-resolution scintillator to detect the residual energy of protons. They used several phantoms irradiated with protons at a proton therapy centre in Krakow, Poland, and measured the phantoms at different angles to obtain reconstructed images by filtered back-projection, used to determine the scanner’s capabilities and validate its use as a proton computed tomography scanner.
According to the results published in The European Physical Journal Plus, the scanner can produce medium-high quality images, with a resolution comparable to other state-of-the-art scanners. The researchers believe that if the system is adequately scaled, it could be used to obtain images of patients before proton therapy, significantly improving the accuracy of treatment planning. "This would optimise dose deposition in cancerous tissue, minimising the exposure of healthy tissue", explains the IFIC researcher.
Reuse of resources
The proton scanner developed through the collaboration between the Institute of Corpuscular Physics, the Institute of Structure of Matter and the Complutense University of Madrid has been built by reusing instrumentation and materials from old prototypes of other nuclear physics projects that were no longer useful for their original purposes. This approach has maximised the reuse of resources without the need to invest in new instrumentation, promoting the efficient and sustainable use of existing resources, according to its promoters.
Reference:
Nácher, E., Briz, J.A., Nerio, A.N. et al. Characterization of a novel proton-CT scanner based on Silicon and LaBr(Ce) detectors.Eur. Phys. J. Plus 139, 404 (2024). https://doi.org/10.1140/epjp/s13360’024 -05203-1
