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The Total Body Irradiation (TBI) is a radiation therapy technique widely used in clinical hemato-oncological treatment of patients that underwent bone marrow transplantation or peripheral stem cell transplantation. Typically, the administration of TBI treatment provides irradiations in 3 consecu-tive days with a double daily fractionation, although other dose fractionation modes have been widely adopted in the clinic procedures. Although this tech-nique allows to irradiate the whole body from head to toes, it has some limitations such as the lack of homogeneity of the dose distribution (which can show varia-tions of 20% in the different areas), irradiation of critical organs such as lungs, liver, intestine and eyeballs that receive a dose comparable to the nominal one and require appropriate shielding and a proper evaluation of the dose absorbed by them. The positive outcome of this type of radiation therapy is closely related to a precise and accurate measurement of dose distribution delivered to the patient in the various body districts. In this work the dose administered in a anthropo-morphic (RANDO) phantom during TBI treatments was evaluated by means EPR dosimetry with alanine. The estimate of the dose was carried out at various points inside the phantom that has been irradiated with a clinical TBI beam configuration by applying a proper shielding provided for the lungs. Doses measured through EPR were compared with those measured with a semiconductor diode

Introduction: Total Body Irradiation (TBI) is a technique widely used in the radiation blood-oncology in the treatment of patients that need bone marrow transplantation or peripheral stem cell transplantation. This technique has some limitations such as the lack of homogeneity of the dose distribution (which may show variations of 20% in the different areas), irradiation of critical organs such as the lungs, the liver, the intestine and the eye-lens which can receive a dose comparable to that nominal and require appropriate shielding and a proper evaluation of the dose absorbed by them. The positive outcome of this type of radiation therapy is strictly related to a precise and accurate measurement of the distribution of the dose delivered to the patient in the various body districts. In this work we performed an analysis by mean of Electron Spin Resonance (ESR) with alanine dosimeters of the doses absorbed in TBI treatment by using and anthropomorphic phantom. Materials and Methods: ESR measurements were performed through the use of commercial alanine pellets. The dosimeters were irradiated with a clinical linear accelerator for the construction of the calibration curve and these values were used for dose calculation of the irradiation of dosimeters in an anthropomorphic phantom. Dose measurements were also performed through a diode. Results: The response of alanine as function of dose is found to be linear. The alanine dose measurements in phantom were compared with those obtained by a diode. Estimated doses with alanine are significantly comparable with the measurements performed with the diode. An underestimation of about 5% was observed with respect the doses planned by the TPS. Conclusions: Alanine dosimetric system present several advantages such as: tissue equivalence, linearity of its dose–response over a wide range, high stability of radiation induced free radicals, no destructive read-out procedure and these features are.

This paper describes the development of a proton Computed Tomography (pCT) apparatus able to reconstruct a map of stopping power useful for accurate proton therapy treatment planning and patient positioning. This system is based on two main components: a silicon microstrip tracker and a YAG:Ce crystal calorimeter. Each proton trajectory is sampled by the tracker in four points: two upstream and two downstream the object under test; the particle residual energy is measured by the calorimeter. The apparatus is described in details together with a discussion on the characterization of the hardware under proton beams with energies up to 175 MeV.

In this paper a proton Computed Radiography (pCR) apparatus for medical applications, realized by PRIMA (PRoton IMAging) Italian Collaboration, is described. The system is oriented to acquire tomography images and meets clinical demands for the use of protons in radiotherapy treatments. The approach proposed here is based on ‘single proton tracking’ method with Most Likely Path (MLP) reconstruction of the single particle. A pCR prototype, with a field of view of about 5×5 cm 2 and an acquisition time of the order of 10 s (10 kHz, 10 5 events), has been developed and tested with a 62 MeV proton beam at the INFN-Laboratori Nazionali del Sud (LNS). The apparatus architecture will be described and first proton radiographies will be shown.

In this paper the use of the Filtered Back Projection (FBP) Algorithm, in order to reconstruct tomographic images using the high energy (200–250 MeV) proton beams, is investigated. The algorithm has been studied in detail with a Monte Carlo approach and image quality has been analysed and compared with the total absorbed dose. A proton Computed Tomography (pCT) apparatus, developed by our group, has been fully simulated to exploit the power of the Geant4 Monte Carlo toolkit. From the simulation of the apparatus, a set of tomographic images of a test phantom has been reconstructed using the FBP at different absorbed dose values. The images have been evaluated in terms of homogeneity, noise, contrast, spatial and density resolution.

A YAG(Ce) crystal has been characterized with a proton beam up to 100 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. A crystal size has been chosen that is able to stop up to 200 MeV. Energy resolution and light response have been measured at Laboratori Nazionali del Sud with a proton beam up to 60 MeV and a spatial homogeneity study of the crystal has been performed at Loma Linda University Medical Center with a 100 MeV proton beam. The YAG(Ce) crystal showed a good energy resolution equal to 3.7% at 60 MeV and measurements, performed in the 30–60 MeV proton energy range, were fitted by Birks' equation. Using a silicon tracker to determine the particle entry point in the crystal, a spatial homogeneity value of 1.7% in the light response has been measured.

The design and the characterization of a calorimeter system, aimed at measuring the residual energy in a proton Computed Tomography (pCT) apparatus, is described. The calorimeter has a 6 × 6 cm2 active area to fully cover the tracker area of the pCT system, being 10 cm thick it is able to stop up to 200 MeV protons and sustain 1 MHz particle rate (average rate on the whole area). The YAG(Ce) scintillator is promising for charged particle detection applications where high-count rate, good energy resolution and compact photodiode readout, not influenced by magnetic fields, are of importance. The aim of this work is to show data acquired with proton beam energy up to 175 MeV and to discuss the performances of this calorimeter.

Glioblastoma multiforme (GBM) is the most common and malignant primary brain tumour, with very poor prognosis. The high recurrence rate and failure of conventional treatments are expected to be related to the presence of radio-resistant cancer stem cells (CSCs) inside the tumour mass. CSCs can both self-renew and differentiate into the heterogeneous lineages of cancer cells. Recent evidence showed a higher effectiveness of C-ions and protons in inactivating CSCs, suggesting a potential advantage of Hadrontherapy compared with conventional radiotherapy for GBM treatment. To investigate the mechanisms involved in the molecular and cellular responses of CSCs to ionising radiations, two GBM stem cell (GSC) lines, named lines 1 and 83, which were derived from patients with different clinical outcomes and having different metabolic profiles (as shown by NMR spectroscopy), were irradiated with 137Cs photons and with protons or C-ions of 62 MeV u-1 in the dose range of 5-40 Gy. The biological effects investigated were: cell death, cell cycle progression, and DNA damage induction and repair. Preliminary results show a different response to ionising radiation between the two GSC lines for the different end points investigated. Further experiments are in progress to consolidate the data and to get more insights on the influence of radiation quality. © The Author 2015.

Laser accelerated proton beams represent nowadays an attractive alternative to the conventional ones and they have been proposed in different research fields. In particular, the interest has been focused in the possibility of replacing conventional accelerating machines with laser-based accelerators in order to develop a new concept of hadrontherapy facilities, which could result more compact and less expensive. With this background the ELIMED (ELIMED: ELI-Beamlines MEDical applications) research project has been launched by LNS-INFN researchers (Laboratori Nazionali del Sud-Istituto Nazionale di Fisica Nucleare, Catania, IT) and ASCR-FZU researchers (Academy of Sciences of the Czech Republic-Fyzikalni ustar, Prague, Cz), within the pan-European ELI-Beamlines facility framework. Its main purposes are the demonstration of future applications in hadrontherapy of optically accelerated protons and the realization of a laser-accelerated ion transport beamline for multidisciplinary applications. Several challenges, starting from laser-target interaction and beam transport development, up to dosimetric and radiobiological issues, need to be overcome in order to reach the final goals. The design and the realization of a preliminary beam handling and dosimetric system and of an advanced spectrometer for high energy (multi-MeV) laser-accelerated ion beams will be shortly presented in this work.

The OFFSET collaboration aims at the development of a novel system for tracking charged particles, designed to achieve real-time imaging, large detection areas, and a high spatial resolution especially suitable for use in medical diagnostics. This paper presents the first prototype of this tracker, having a 20×20 cm2 sensitive area made by two crossed ribbons of 500 μ m square scintillating fibers. The track position information is extracted in real time using a reduced number of read-out channels to obtain very large detection area at moderate cost and complexity. The performance of the tracker was investigated using β sources, cosmic rays and a 62 MeV proton beam.

A YAG:Ce calorimeter with a 6×6 cm2 active area, long 10 cm has been manufactured in order to stop up to 200 MeV protons and to sustain 1MHz particle rate. It consists of four optically separated crystals assembled in the same housing. The YAG:Ce scintillator is promising for charged particle detection applications where high-count rate, good energy resolution and compact photodiode readout, not influenced by magnetic fields, are of importance. The YAG:Ce calorimeter has been characterized with proton beams up to 175MeV a The Svedberg Laboratory (TSL), Uppsala Sweden. Results obtained are shown and discussed.

This paper reports on the activity of the INFN PRIMA/RDH collaboration in the development of proton Computed Tomography (pCT) systems based on single proton tracking and residual energy measurement. The systems are made of a silicon microstrip tracker and a YAG:Ce crystal calorimeter to measure single protons trajectory and residual energy, respectively. A first prototype of pCT scanner, with an active area of about 5 × 5 cm2 and a data rate capability of 10 kHz, has been constructed and characterized with 62 MeV protons at INFN Laboratori Nazionali del Sud in Catania (Italy) and with 180 MeV protons at The Svedberg Laboratory (TSL) in Uppsala (Sweden). Results of these measurements, including tomographic reconstructions of test phantoms, will be shown and discussed. An upgraded system with an extended field of view (up to ~ 5 × 20 cm2) and an increased event rate capability up to one MHz, presently under development, will be also described.

Nowadays, laser-driven proton beams generated by the interaction of high power lasers with solid targets represent a fascinating attraction in the field of the new acceleration techniques. These beams can be potentially accelerated up to hundreds of MeV and, therefore, they can represent a promising opportunity for medical applications. Laser-accelerated proton beams typically show high flux (up to 1011 particles per bunch), very short temporal profile (ps), broad energy spectra and poor reproducibility. In order to overcome these limitations, these beams have be controlled and transported by means of a proper beam handling system. Furthermore, suitable dosimetric diagnostic systems must be developed and tested. In the framework of the ELIMED project, we started to design a dedicated beam transport line and we have developed a first prototype of a beam line key-element: an Energy Selector System (ESS). It is based on permanent dipoles, capable to control and select in energy laser-accelerated proton beams. Monte Carlo simulations and some preliminary experimental tests have been already performed to characterize the device. A calibration of the ESS system with a conventional proton beam will be performed in September at the LNS in Catania. Moreover, an experimental campaign with laser-driven proton beam at the Centre for Plasma Physics, Queens University in Belfast is already scheduled and will be completed within 2014.

A high energy resolution, high dispersive power Thomson Parabola Spectrometer has been developed at INFN-LNS in order to characterize laser-driven beams up to 30- 40 MeV for protons. This device has parallel electric and magnetic field to deflect particles of a certain charge-to-mass ratio onto parabolic traces on the detection plane. Calibration of the deflection sector is crucial for data analysis, namely energy determination of analysed beam, and to evaluate the effective energy limit and resolution. This work reports the study of monochromatic proton beams delivered by the TANDEM accelerator at LNS (Catania) in the energy range between 6 and 12.5 MeV analysed with our spectrometer which allows a precise characterization of the electric and magnetic deflections. Also the energy and the Q/A resolutions and the energy limits have been evaluated proposing a mathematical model that can be used for data analysis, for the experimental set up and for the device scalability for higher energy.

In this paper we describe a new detection system for the high resolution measurement of the residual range of charged particles, designed and developed with the aim of achieving real-time data acquisition and large detection areas. A prototype of the residual range detector, with a sensitive area of about 4 × 4 cm2, consisting of a stack of sixty ribbons of scintillating fibers (Sci-Fi) has been designed and tested. Each layer is read-out by two wavelength shifter (WLS) fibers and a position sensitive photomultiplier (PSPM). The Bragg peak shape is calculated real-time by the time over a suitable threshold for each channel. The results of the measurements taken using the prototype and a 62 MeV proton beam and a comparison with the GEANT4 simulations of the detector are presented. The main concepts on which the prototype is based have been used to demonstrate the technique patented by the INFN. The next step will be to design and validate the final detector which will have 30 × 30 cm2 FOV and cover the 250 MeV proton range with about 150 micron range resolution. These performances are suitable for almost all medical imaging applications.

The design of a detector for tracking charged particles is presented together with the characterization techniques developed to extract the main design specifications. The goals for the final detector are to achieve real-time imaging performances, a large detection area, and a high spatial resolution, particularly suitable for medical imaging applications. This paper describes the prototype of the tracker plane, which has a 20 × 20 cm2sensitive area consisting of two crossed ribbons of 500 μm square scintillating fibers. The information about the hit position extracted real-time tracker in an innovative way, using a reduced number of the read-out channels to obtain a very large detection area but with moderate costs and complexity. The performances of the tracker have been investigated usingβsources, cosmic rays, and a 62 MeV proton beam.

Hadron therapy for tumor treatment is nowadays used in several medical centres. The main advantage in using protons or light ions beams is the possibility of tightly shaping the radiation dose to the target volume. Presently the spatial accuracy of the therapy is limited by the uncertainty in stopping power distribution, which is derived, for each treatment, from the photon attenuation coefficients measured by X-ray tomography. A direct measurement of the stopping powers will help in reducing this uncertainty. This can be achieved by using a proton beam and a detection system able to reconstruct a tomography image of the patient. As a first step towards such a system an apparatus able to perform a proton transmission radiography (pCR) has been designed. It consists of a silicon microstrip tracker, measuring proton trajectories, and a YAG:Ce calorimeter to determine the particle residual energy. Proton beam and laboratory tests have been performed on the system components prototypes: the main results will be shown and discussed.

The present study was aimed at verifying the automatic registration of the Focal (Elekta) platform with a dedicated phantom. A phantom that simulates the pelvis region in a stylised way and finalised to the registration of computed tomography–magnetic resonance images was designed and realised. After acquiring the two sets of images, the registration was performed both in automatic and manual mode to verify whether they were comparable. To test the repeatability of the automatic registration, some known rigid transformations were imposed to the original images. If the registration method works correctly, parameters which bring the images into alignment must always be the same. Automatic registration performed by the software did not prove satisfactory, whereas if a specific tool [volume of interest (VOI) tool] allowing the calculation to be limited to the landmark region was used, the registration parameters were comparable with those of the manual registration. Regarding the repeatability of the automatic registration, the software brought the images in the correct alignment performing translations and rotations along the longitudinal axis up to 40°, while it was not satisfactory for rotations along the transverse axes. The experimental results showed that in clinical application automatic registration is reliable if the VOI tool that includes visible landmarks in both studies is used. However, because the algorithm did not prove sensitive to rotations along the transverse axes, the position of the patient during the examinations plays a crucial role.

The PRIMA (Proton IMAging) experiment is aimed at developing a proton Computed Tomography (pCT) prototype based on tracking single protons. Approaches to the pCT consist in the use of silicon microstrip detectors to measure the position and direction of individual protons before and after they traverse the phantom, in view to reconstruct the trajectory of each proton, and a calorimeter for measuring particle residual energy. A small prototype was tested, under 62 MeV proton beam at Laboratory Nazionali del Sud, (Catania Italy) and under 180 MeV proton beam at Svedberg Laboratories, Uppsala Universitet, (Uppsala Sweden). Several experiments concerning proton imaging, tomography and radiography, were carried out during these beam tests. Radiographies have been reconstructed with different methods: results show the good performances of the device, with spatial resolution fulfilling the stringent requirements of a pCT device.

Proton Computed Tomography (pCT) is a medical imaging technique based on the use of proton beams with energies above 200 MeV to directly measure stopping power distributions inside the tissue volume. Prima (PRoton IMAging) is an Italian collaboration working on the development of a pCT scanner based on a tracker and a calorimeter to measure single protons trajectory and residual energy. The tracker is composed of four planes of silicon microstrip detectors to measure proton entry and exit positions and angles. Residual energy is measured by a calorimeter composed of YAG:Ce scintillating crystals. A first prototype of pCT scanner, with an active area of about 5×5 cm2, has been constructed and characterized with 60 MeV protons at the INFN Laboratori Nazionali del Sud, Catania (Italy) and with 180 MeV protons at Svedberg Laboratory, Uppsala (Sweden). A new pre-clinical prototype with an extended active area up to 20×5 cm2, real time data acquisition and a data rate up to 1 MHz is under development. A description of the two prototypes will be presented together with first results concerning tomographic image reconstruction.

Proton Computed Tomography (pCT) is a new imaging method with a potential for increasing accuracy of treatment planning and patient positioning in hadron therapy. A pCT system with small active area (5cm×5cm) has been already manufactured by authors. Tested under proton beams gave first promising results on radiography and tomographic reconstructions. Recent developments of a second prototype with large area (5×20cm2) in the perspective of a pre-clinical acquisition system is now being designed, details are given in this paper.

This paper presents the design flow of a detector for tracking charged particles together with the characterization techniques developed to extract the main design specifications. The goals for the final detector are to achieve real-time imaging, a large detection area and a high spatial resolution particularly suitable for medical imaging applications. The main concepts have been patented by the INFN. This paper describes the prototype tracker, which has a 20x20 cm2 sensitive area consisting of two crossed ribbons of 500 µm square scintillating fibers. The track position information is real-time extracted in an innovative way, using a reduced number of read-out channels to obtain a very large detection area but with moderate costs and complexity. The performance of the tracker has been investigated using s sources, cosmic rays, and a 62 MeV proton beam.

The prototype of the OFFSET (Optical Fiber Folded Scintillating Extended Tracker) tracker is presented. It exploits a novel system for particle tracking, designed to achieve real-time imaging, large detection areas, and a high spatial resolution especially suitable for use in medical diagnostics. The main results regarding the system architecture have been used as a demonstration of the technique which has been patented by the Istituto Nazionale di Fisica Nucleare (INFN). The prototype of this tracker, presented in this paper, has a 20 × 20 cm2 sensitive area, consisting of two crossed ribbons of 500 micron square scintillating fibers. The track position information is extracted in real time in an innovative way, using a reduced number of read-out channels to obtain very large detection area with moderate enough costs and complexity. The performance of the tracker was investigated using beta sources, cosmic rays, and a 62 MeV proton beam.

Introduction DBT is a new image system that needs to be evaluated in terms of image quality and performance. Purpose The aim of this work is the implementation of a quality control protocol in digital breast tomosynthesis with the aid of different phantoms and the comparison of results obtained on two Hologic Selenia Dimensions mammography systems. Materials and methods We analyzed several aspects of DBT systems such as X-ray generation, image receptor, image quality of the reconstructed images and dosimetry. We evaluated focal spot motion measuring projection, the exposure time and the time for a complete scan. We verified the stability of the exposure distribution over the projections. We also measured image receptor response, uncorrected defective detector elements and detector homogeneity on reconstructed images. We assessed in-plane projection and system MTF at different positions above the bucky with edge phantoms made of different materials and thicknesses. We also measured in-plane projection MTF using a tungsten wire. We evaluated Z-resolution with different diameter aluminum spheres and a tungsten wire. We made an artifact analysis with different phantoms and we assessed NNPS for the standard breast thickness at clinically selected parameters and with different doses. We investigated in-plane image quality in different noise conditions with CDMAM phantom. Finally, we assessed AGD for different breast thicknesses to be compared with AGD in FFDM for the same thicknesses and with AGD displayed by the system. Results and conclusion The performance of the two different equipment tested were comparable and close to the values found in literature.

In this paper we describe a novel system for the tracking of charged particles, designed to achieve real-time imaging, large detection areas and high spatial resolution especially suitable for use in medical diagnostic. A prototype of this tracker, having a 20 × 20 cm2 sensitive area, consisting of two crossed ribbons of 500 11m square scintillating fibers has been developed. The track position information is extracted real time in an innovative way, using a reduced number of read-out channels to obtain very large detection area with enough moderate costs and complexity. The performances of the tracker have been investigated using both β sources and cosmic rays and finally with a 62 MeV proton beam.

One of the particular characteristics of diamond detectors is their fast charge collection time. This feature makes these detectors very attractive for timing measurements in both nuclear and particle physics experiments. The charge collection time in these detectors is of the order of a few hundred ps, therefore the timing performance depends greatly on the electronics readout of the detector. In this work we present comparative measurements made using a single crystal diamond detector and two different electronic readout chains. In particular, we used a charge sensitive amplifier (CSA) with a 100 MHz bandwidth and a voltage amplifier with a 2 GHz bandwidth. In order to evaluate the performance of the detector for charge signals generated by particles with energies below minimum ionizing, measurements were taken using 62 MeV proton beam at the INFN - Laboratori Nazionali del Sud. Another set of measurements was made with a 120 GeV proton beam at FNAL in order to evaluate the performance with MIP. The timing performance depends on the rise time of the signal and the Signal to Noise ratio. Both these characteristics are inversely related to the electronic readout bandwidth. The charge collection with the 62 MeV proton beam was about 130 Ke-. A SIN ratio of about 80 was obtained with the CSA, while the SIN ratio was approximately 4 with the 2 GHz broad-band amplifier. This resulted in a comparable time distribution value of around 70 ps RMS in both cases. However, charge collection is much smaller with minimum ionizing particles, and while it was possible to perform measurements with the CSA, with the broadband amplifier it was not possible to separate signals from the background noise. In this work we present and discuss the set-up used and the complete set of measurements, with final considerations regarding range of use to which these detector can be utilized.

Proton therapy is a highly precise form of cancer treatment, which requires accurate knowledge of the dose delivered to the patient and verification of the correct patient position to avoid damage to critical normal tissues. The development of pCT (proton Computed Tomography) system represents an important feature for precise proton radiation treatment planning because it could permit the direct measurement of the proton stopping power distribution, improving the accuracy in dose calculus, and the patient's position. A pCT prototype was manufactured in order to demonstrate the capability to acquire, during treatments in proton therapy centers, radiographic and tomographic images according to clinical demands.

ELI-Beamlines is one of the four pillars of the ELI (Extreme Light Infrastructure) pan-European project. It will be an ultrahigh-intensity, high repetition-rate, femtosecond laser facility whose main goals are the generation and applications of high-brightness X-ray sources and accelerated charged particles. In particular medical and multidisciplinary applications with laser-accelerated beams are treated by the ELIMED task force, a collaboration between different research institutes. A crucial goal for this network is represented by the design and the realization of a transport beamline able to provide ion beams with suitable characteristics in terms of energy spectrum and angular distribution in order to perform dosimetric tests and biological cell irradiations. A first prototype of transport beamline has been already designed and some magnetic elements are already under construction. In particular, an Energy Selector System (ESS) prototype has been already realized at LNS-INFN. This paper reports about the studies of the ESS properties as, for instance, energy spread and transmission efficiency, carried out using the GEANT4 Monte Carlo code.

Proton Computed Tomography (pCT) is an imaging method under investigation with the aim to improve the accuracy of treatment planning and patient positioning in hadron therapy. A pCT system should be capable to measure tissue electron density with an accuracy better than 1% and with a spatial resolution better than 1mm. A first apparatus based on a silicon tracker and a YAG:Ce crystal calorimeter, with a 5×5 cm2 active area, has been already developed by the authors in the framework of the PRIMA (Proton Imaging) collaboration and tested with proton beams with promising results. A second prototype with larger area (5×20 cm2) and improved data acquisition system is being designed. The details about this new prototype will be presented in this work.