PT Journal
AU Solevi, P
   Muñoz, E
   Solaz, C
   Trovato, M
   Dendooven, P
   Gillam, JE
   Lacasta, C
   Oliver, JF
   Rafecas, M
   Torres-Espallardo, I
   Llosa, G
TI Performance of MACACO Compton telescope for ion-beam therapy monitoring: first test with proton beams
SO Physics in Medicine and Biology
JI Phys. Med. Biol.
PY 2016
BP 5149
EP 5165
VL 61
IS 14
DI 10.1088/0031-9155/61/14/5149
LA English
DE ion-beam therapy; range verification; prompt gamma; Compton camera; GATE
AB In order to exploit the advantages of ion-beam therapy in a clinical setting, delivery verification techniques are necessary to detect deviations from the planned treatment. Efforts are currently oriented towards the development of devices for real-time range monitoring. Among the different detector concepts proposed, Compton cameras are employed to detect prompt gammas and represent a valid candidate for real-time range verification. We present the first on-beam test of MACACO, a Compton telescope (multi-layer Compton camera) based on lanthanum bromide crystals and silicon photo-multipliers. The Compton telescope was first characterized through measurements and Monte Carlo simulations. The detector linearity was measured employing Na-22 and Am-Be sources, obtaining about 10% deviation from linearity at 3.44 MeV. A spectral image reconstruction algorithm was tested on synthetic data. Point-like sources emitting gamma rays with energy between 2 and 7 MeV were reconstructed with 3-5 mm resolution. The two-layer Compton telescope was employed to measure radiation emitted from a beam of 150 MeV protons impinging on a cylindrical PMMA target. Bragg-peak shifts were achieved via adjustment of the PMMA target location and the resulting measurements used during image reconstruction. Reconstructed Bragg peak profiles proved sufficient to observe peak-location differences within 10 mm demonstrating the potential of the MACACO Compton Telescope as a monitoring device for ion-beam therapy.
ER