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J-PET application as a Compton camera for proton beam range verification: A preliminary study

Kozani Majid, Rucinski Antoni, Moskal Pawel

Bio-Algorithms and Med-Systems

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2023

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Vol. 19, no. 1

23--30

EN

Hybrid in-beam PET/Compton camera imaging currently shows a promising approach to use of the quasi-real-time range verification technique in proton therapy. This work aims to assess the capability of utilizing a configuration of the Jagiellonian-positron emission tomography (J-PET) scanner made of plastic scintillator strips, so as to serve as a Compton camera for proton beam range verification. This work reports the production yield results obtained from the GATE/Geant4 simulations, focusing on an energy spectrum (4.2-4.6) MeV of prompt gamma (PG) produced from a clinical proton beam impinging on a water phantom. To investigate the feasibility of J-PET as a Compton camera, a geometrical optimisation was performed. This optimisation was conducted by a point spread function (PSF) study of an isotropic 4.44 MeV gamma source. Realistic statistics of 4.44 MeV PGs obtained from the prior step were employed, simulating interactions with the detector. A sufficient number of detected photons was obtained for the source position reconstruction after performing a geometry optimisation for the proposed J-PET detector. Furthermore, it was demonstrated that more precise calculation of the total deposited energy of coincident events plays a key role in improving the image quality of source distribution determination. A reasonable spatial resolution of 6.5 mm FWHM along the actual proton beam direction was achieved for the first imaging tests. This preliminary study has shown notable potential in using the J-PET application for in-beam PET/Compton camera imaging at quasi-real-time proton range monitoring in future clinical use.

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Estimating influence of positron range in proton-therapy-beam monitoring with PET

Mryka Wiktor, Das Manish, Beyene Ermias Y., Moskal Paweł, Stępień Ewa

Bio-Algorithms and Med-Systems

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2023

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Vol. 19, no. 1

96--100

EN

The application of PET scanners to proton-beam-therapy monitoring is a promising solution to obtain the range of the beam and hence the positions of a Bragg peak - maximum dose deposition point. A proton beam induces nuclear reactions in the tissue, leading to the production of isotopes that emit β+ radiation. This enables the imaging of the density distribution of β+ isotopes produced in the body, allowing the reconstruction of the proton beam range. Moreover, PET detectors may open the possibility for in-beam monitoring, which would offer an opportunity to verify the range during irradiation. PET detectors may also allow positronium imaging, which would be the indicator of the tissue conditions. However, the image of annihilation points does not represent the range of the proton beam. There are several factors influencing the translation from annihilation points to obtain the Bragg peak position. One of them is the kinetic energy of the positron. This energy corresponds to some range of the positron within the tissue. In this manuscript we estimate positron energy and its range and discuss its influence on proton therapy monitoring.

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Towards high sensitivity and high-resolution PET scanners: imaging-guided proton therapy and total body imaging

Lang Karol

Bio-Algorithms and Med-Systems

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2022

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Vol. 18, no. 1

96--106

EN

Quantitative imaging (i.e., providing not just an image but also the related data) guidance in proton radiation therapy to achieve and monitor the precision of planned radiation energy deposition field in-vivo (a.k.a. proton range verification) is one of the most underinvested aspects of radiation cancer treatment despite that it may dramatically enhance the treatment accuracy and lower the exposure related toxicity improving the entire outcome of cancer therapy. In this article, we briefly describe the effort of the TPPT Consortium (a collaborative effort of groups from the University of Texas and Portugal) on building a time-of-flight positronemission-tomography (PET) scanner to be used in preclinical studies for proton therapy at MD Anderson Proton Center in Houston. We also discuss some related ideas towards improving and expanding the use of PET detectors, including the total body imaging.

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Ambient dose equivalent measurements in secondary radiation fi elds at proton therapy facility CCB IFJ PAN in Krakow using recombination chambers

Jakubowska E. A., Gryziński M. A., Golnik N., Tulik P., Stolarczyk L., Horwacik T., Zbroja K., Góra Ł.

Nukleonika

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2016

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Vol. 61, No. 1

23--28

EN

This work presents recombination methods used for secondary radiation measurements at the Facility for Proton Radiotherapy of Eye Cancer at the Institute for Nuclear Physics, IFJ, in Krakow (Poland). The measurements of H*(10) were performed, with REM-2 tissue equivalent chamber in two halls of cyclotrons AIC-144 and Proteus C-235 and in the corridors close to treatment rooms. The measurements were completed by determination of gamma radiation component, using a hydrogen-free recombination chamber. The results were compared with the measurements using rem meter types FHT 762 (WENDI-II) and NM2 FHT 192 gamma probe and with stationary dosimetric system.

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Influence of the energy spectrum and spatial spread of proton beams used in eye tumor treatment on the depth-dose characteristics

Konefał A., Szaflik P., Zipper W.

Nukleonika

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2010

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Vol. 55, No. 3

313-316

EN

The influence of the energy spectrum and the spatial spread of a therapeutic proton beam impinging on an irradiated medium (called the entrance beam) on the depth-dose characteristics in water, in the proton energy range of 50 division sign 70 MeV was studied. It turns out that full width at half maximum (FWHM) of the Bragg peak increases almost linearly with increasing proton energy. It ranges from 1.53 mm for 50 MeV to 2.59 mm for 70 MeV, for monoenergetic protons. Moreover, the significant influence of the energy spread of the entrance proton beam on the intensity and FWHM of the Bragg peak is visible. FWHM of the Bragg peak of 60 MeV protons is equal to 2.03, 3.37 and 5.86 mm for a monoenergetic beam and beams with an energy spread of 0.5 and 1 MeV SD (standard deviation), respectively. The intensity of the Bragg peak of a 60 MeV proton beam with an energy spread of 1 MeV SD is approximately 25% less than that for a monoenergetic beam. Moreover, the Bragg peak shifts to smaller depths as the energy spread of the entrance beam increases. The shift of the peak is about 0.2÷0.3 mm for a beam with an energy spread of 0.5 MeV SD and between 0.4 division sign 0.5 mm for an energy spread of 1 MeV SD, compared with a monoenergetic beam in the energy range from 50 to 60 MeV. However, the spatial spread of the entrance proton beam does not affect significantly the depth-dose characteristic.

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Status report of the PSI high power proton cyclotrons

Humbel M., Adam S., Mezger A.

Nukleonika

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2003

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Vol. 48,suppl.2

141-144

EN

In addition to its traditional activities, of improving the availability of its 1 megawatt proton beam, the PSI cyclotron department has started two new projects. One of these is a further increase of the accelerated beam intensity towards 3 mA, the other one is a substantial enhancement of the proton therapy facility.

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Status report of the LNS Superconducting Cyclotron

Rifuggiato D., Calabretta L., Cuttone G.

Nukleonika

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2003

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Vol. 48,suppl.2

131-134

EN

The LNS Superconducting Cyclotron has been working in stand alone mode since the beginning of 2000, after 5 years of operation as a booster of the 15 MV Tandem. The new mode has proven to be by far more advantageous than the previous one from the point of view of operation. Working with axial injection, a quite high number of new beam types has been developed. The new mode allows for acceleration of H2 + molecules, which break into two protons when crossing a stripper in the beam line out of the cyclotron. 62 MeV protons have been used for radiotherapy since February 2002. The new mode allows to inject a more intense beam as compared to the previous mode. Therefore, an upgrading program of the cyclotron has started, aiming at having an intense extracted beam to be used as a primary beam in a facility for production of radioactive beams. Beam tests have been accomplished to evaluate transmission figures, while the upgrading of the present electrostatic deflectors has started: new deflector systems, able to dissipate high beam power and allowing for easier maintenance, have been designed and will soon be tested in the machine.