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In recent years one of the areas of interest in radiotherapy has been adaptive radiation therapy (ART), with the most efficient way of performing ART being the use of deformable image registration (DIR). In this paper we use the distances between points of interest (POIs) in the computed tomography (CT) and the cone beam computed tomography (CBCT) acquisition images and the inverse consistence (IC) property to validate the RayStation treatment planning system (TPS) DIR algorithm. This study was divided into two parts: Firstly the distance-accuracy of the TPS DIR algorithm was ascertained by placing POIs on anatomical features in the CT and CBCT images from five head and neck cancer patients. Secondly, a method was developed for studying the implication of these distances on the dose by using the IC. This method compared the dose received by the structures in the CT, and the structures that were quadruply-deformed. The accuracy of the TPS was 1.7 ± 0.8 mm, and the distance obtained with the quadruply-deformed IC method was 1.7 ± 0.9 mm, i.e. the difference between the IC method multiplied by two, and that of the TPS validation method, was negligible. Moreover, the IC method shows very little variation in the dose-volume histograms when comparing the original and quadruply-deformed structures. This indicates that this algorithm is useful for planning adaptive radiation treatments using CBCT in head and neck cancer patients, although these variations must be taken into account when making a clinical decision to adapt a treatment plan. [ABSTRACT FROM AUTHOR]

The SYRMEP (SYnchrotron Radiation for MEdical Physics) beamline at Elettra is performing the first mammography study on human patients using free-space propagation phase contrast imaging. The stricter spatial resolution requirements of this method currently force the use of conventional films or specialized computed radiography (CR) systems. This also prevents the implementation of three-dimensional (3D) approaches. This paper explores the use of an X-ray detector based on complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) technology as a possible alternative, for acquisitions both in planar and tomosynthesis geometry. Results indicate higher quality of the images acquired with the synchrotron set-up in both geometries. This improvement can be partly ascribed to the use of parallel, collimated and monochromatic synchrotron radiation (resulting in scatter rejection, no penumbra-induced blurring and optimized X-ray energy), and partly to phase contrast effects. Even though the pixel size of the used detector is still too large – and thus suboptimal – for free-space propagation phase contrast imaging, a degree of phase-induced edge enhancement can clearly be observed in the images. [ABSTRACT FROM AUTHOR]

Accurate characterisation of the scanner's point spread function across the entire field of view (FOV) is crucial in order to account for spatially dependent factors that degrade the resolution of the reconstructed images. The HRRT users' community resolution modelling reconstruction software includes a shift-invariant resolution kernel, which leads to transaxially non-uniform resolution in the reconstructed images. Unlike previous work to date in this field, this work is the first to model the spatially variant resolution across the entire FOV of the HRRT, which is the highest resolution human brain PET scanner in the world. In this paper we developed a spatially variant image-based resolution modelling reconstruction dedicated to the HRRT, using an experimentally measured shift-variant resolution kernel. Previously, the system response was measured and characterised in detail across the entire FOV of the HRRT, using a printed point source array. The newly developed resolution modelling reconstruction was applied on measured phantom, as well as clinical data and was compared against the HRRT users' community resolution modelling reconstruction, which is currently in use. Results demonstrated improvements both in contrast and resolution recovery, particularly for regions close to the edges of the FOV, with almost uniform resolution recovery across the entire transverse FOV. In addition, because the newly measured resolution kernel is slightly broader with wider tails, compared to the deliberately conservative kernel employed in the HRRT users' community software, the reconstructed images appear to have not only improved contrast recovery (up to 20% for small regions), but also better noise characteristics. [ABSTRACT FROM AUTHOR]

PET image quality is directly associated with two important parameters among others: count-rate performance and image signal-to-noise ratio (SNR). The framework of noise equivalent count rate (NECR) was developed back in the 1990s and has been widely used since then to evaluate count-rate performance for PET systems. The concept of NECR is not entirely straightforward, however, and among the issues requiring clarification are its original definition, its relationship to image quality, and its consistency among different derivation methods. In particular, we try to answer whether a higher NECR measurement using a standard NEMA phantom actually corresponds to better imaging performance. The paper includes the following topics: 1) revisiting the original analytical model for NECR derivation; 2) validating three methods for NECR calculation based on the NEMA phantom/standard; and 3) studying the spatial dependence of NECR and quantitative relationship between NECR and image SNR. [ABSTRACT FROM AUTHOR]

Physica Medica – European Journal of Medical Physics (EJMP) is the official journal of Société Française de Physique Médicale. In the last five years, France ranked second in the list of 57 countries contributing papers to EJMP, and article downloads from France are No. 7 in the list of 111 countries where EJMP is read. Five of the sixty Associate Editors of EJMP are based in France. EJMP is also the offical journal of EFOMP and it aims at representing the reference scientific journal for all European medical physicists. EJMP is looking for continuous support from French medical physicists via submission of their best papers and by active participation in the editorial team activities. These include increasing the number of submissions, still limited with respect to the potential scientific impact of the large community of French medical physicists, as well as taking on new editorial tasks and roles. In this communication the Editor-in-Chief describes the current numbers and facts of EJMP and encourages his French colleagues, in particular the young medical physicists, to actively participate to the life of their scientific journal. [ABSTRACT FROM AUTHOR]

Purpose Scientists disagree on how to interpret risks from low dose radiation exposures. In particular, publications which rely on the Linear No Threshold (LNT) model for estimating of the number of future cancers that may be caused by medical x-rays have led to considerable debate. Some scientific bodies have described such estimates as “highly speculative”. There has also been criticism of a commonly used dose metric, Effective Dose (ED), which it is argued, should be used for “radiation protection purposes” only. Methods This paper offers a partial defence of estimates of cancer risk in a population after exposure to low dose x-rays. We argue that (i) ED is too readily dismissed as a tool for estimating risks in a population, and (ii) that the context for the unmeasurable risk from low dose x-rays is not always given sufficient attention. Results On the first point we argue that criticisms cataloguing the averaging assumptions underpinning the estimation of ED can only be used to calculate an error bar; the conclusion that ED cannot be used in risk estimates because of this error bar does not follow. Secondly, we criticize the use of the term “highly speculative” for risk from exposures below 50 mSv. It is easy to suppose that if science cannot detect a risk, then that risk must be negligible: however, this ignores the fact that because cancer is a common disease, x-rays would have to cause large numbers of cancers before the risk could be detected. In this context, unmeasurable risk cannot be equated to inconsequential risk. Conclusions Confusion about radiation risks has the potential to disrupt the optimum use of medical imaging technology. This paper argues against views which give insufficient weight to low dose radiation risk [1,2] . [ABSTRACT FROM AUTHOR]

The use of optical methods for the detection of radionuclides is becoming an established tool for preclinical molecular imaging experiments. In this paper we present a set of proof of principle experiments showing that planar bremsstrahlung radiation images can be detected with an intensifying screen using a small animal optical imager based on charge coupled device detector. We develop a bremsstrahlung source using a 32 P-ATP vial placed in a Plexiglas box, the source with an intensifying screen on top was placed inside a small animal optical imaging system. Bremsstrahlung radiation images were produced with the 32 P-ATP source only and also with a pair of pliers placed between the source and the screen. We found that the pair of pliers absorption image matches the shape of the object. Spatial resolution measurements were not performed however, the bremsstrahlung image of the pliers show that the resolution is relatively poor due to a large penumbra effect. We conclude that it is possible to produce planar bremsstrahlung images using optical imaging devices. [ABSTRACT FROM AUTHOR]

Medical physics, both as a scientific discipline and clinical service, hugely contributed and still contributes to the advances in the radiotherapy of prostate cancer. The traditional translational role in developing and safely implementing new technology and methods for better optimizing, delivering and monitoring the treatment is rapidly expanding to include new fields such as quantitative morphological and functional imaging and the possibility of individually predicting outcome and toxicity. The pivotal position of medical physicists in treatment personalization probably represents the main challenge of current and next years and needs a gradual change of vision and training, without losing the traditional and fundamental role of physicists to guarantee a high quality of the treatment. The current focus issue is intended to cover traditional and new fields of investigation in prostate cancer radiation therapy with the aim to provide up-to-date reference material to medical physicists daily working to cure prostate cancer patients. The papers presented in this focus issue touch upon present and upcoming challenges that need to be met in order to further advance prostate cancer radiation therapy. We suggest that there is a smart future for medical physicists willing to perform research and innovate, while they continue to provide high-quality clinical service. However, physicists are increasingly expected to actively integrate their implicitly translational, flexible and high-level skills within multi-disciplinary teams including many clinical figures (first of all radiation oncologists) as well as scientists from other disciplines. [ABSTRACT FROM AUTHOR]

In the seventies, several Monte Carlo programs were available in radiation physics. I had already developed a home-made Monte Carlo code for neutron transport to validate the experimental measurements of the efficiency of a large neutron counter for 10–200 MeV neutrons in a HEP experiment, when I participated at the first international on “Computer techniques in radiation transport and dosimetry”, organized by Walter R. Nelson and Theodore Jenkins in Erice (Trapani, Italy) in 1978: Graham Stevenson, Keran O’Brien, W. W. Engle, T. A. Gabriel, C. Ponti, Walter R. Nelson, Herbert Dinter, A. Van Ginneken, Tony W. Armstrong and J. Ranft were the speakers. It was there that I met with the EGS code and its author Walter Ralph Nelson. Since then I started my collaboration with Ralph Nelson on the use of the EGS3 Monte Carlo in Nuclear Medicine, with the first paper published in 1980 on Compton Tomography, followed by a series of papers on the simulation of the performance of a human PET based on MWPC’s, the first one in 1981. From these first wails in the PET domain EGS3 became EGS4 and then evolved into GEANT and finally into GATE to become an indispensable code for PET detector simulation. In this talk I will present my pristine research in the field of PET Monte Carlo simulations in the last 20 years of last century. [ABSTRACT FROM AUTHOR]

Purpose The aim of this work was to undertake/experience an online survey to interact with user, patients and healthcare professionals. The survey had a twofold objective: first, to get users aware on the ongoing changes in Hospital-to-patient interaction due to the imminent transposition of the Directive EURATOM-59/2013, that is the communication of radiation dose data in X-ray medical exposures; therefore, to evaluate the perception of the radiation risk and to identify the participants' preferred way to communicate them the amount of radiation dose. Methods The survey was developed on the website SurveyMonkey and published at the address https://it.surveymonkey.com/r/NOSRadion. Users could access the survey by registering personal @mail address to a dedicated mailing-list, by visiting the Hospital website and by scanning a QR-code. No paper forms of the survey were proposed. The survey was developed to be brief and easy-to-read through three sections. In the first section personal data were recorded. In the second section, the personal feeling (interest and concern) with radiation risk connected to medical exposures was evaluated. In the last section, the preferred way to communicate dose to the patients was investigated by proposing several quantitative and qualitative options. Target recruiting group is established to 500 users. Results A recap of the preliminary analysis based on the answers collected from the first 143 survey users (covered by around 70% by non-professionals) are shown in Table 1 and indicates a strong interest in the topic of radiation dose due to medical exposure, even if it was not coupled to great concern. Numerical quantification of the dose data was chosen by most of participants. Mean time for survey completion was about 5 min. Conclusions Online survey showed to be an efficient and very low-cost way to interact with user/patients and a powerful tool to get qualitative information potentially useful to define management strategies. Survey outcomes are considered for future development of the Hospital environment. [ABSTRACT FROM AUTHOR]

Introduction Promoting of education and training programmes is one of the columns of the mission of EFOMP. In this paper, I will briefly outline the initiatives taken from EFOMP in this field, namely: -The European School for medical Physics Experts (ESMPE) -The European Examination Board (EEB) - The participation of EFOMP in the EUTEMPE-RX network. ESMPE EFOMP organized in 2013 the first module which was targeted towards Medical Physicists who would like to achieve Medical Physics Expert status in the Nuclear Medicine subspecialty. Since then, nine editions of the school have been completed with more than 400 participants coming from all European countries (see Fig. 1). The geographical distribution of participants demonstrate that this is perceived by participants as a European forum where state of the art information regarding technologies, methods and novelties in the field of medical Physics can be efficiently gathered and shared (see Fig. 2). A distinctive tract of the school is to provide subsidized fees for a certain number of participants coming from low income European countries. ESMPE at the second European Congress of Medical Physics – August 22, 2018, Copenhagen, Denmark The main congress (ECMP2018) will take place from 23 to 25 August 2018 in Copenhagen. Satellite meetings will be held in conjunction with the ECMP2018 on the 22 of August. Among them, ESMPE organized three satellite meetings. 1. Statistics in Medical Physics 2. Fundamentals of Nuclear Medicine Dosimetry 3. IMRT&VMAT planning in practice EEB In many of EFOMP's NMOs a local examination board has not been established. Currently medical physicists from such countries face difficulties in providing the necessary qualification evidence when they seek employment in other EU Member States. The EEB has been established to facilitate the harmonization of medical physics standards throughout Europe, so facilitating the mobility of medical physicists The EEB main aims are to introduce 2 European Diplomas in Medical Physics: • EDMP (European Diploma for Medical Physics) • EACMPE (European Accreditation Certificate for Medical Physics Experts) The first round of EEB exams for Diagnostic and Interventional radiology took place in Prague July 6 and 7 2017. The second EEB round of examinations will took place August 21 and 22 2018 in all three fields of Medical Physics and will be held in conjunction with the 2nd ECMP 2018 in Copenhagen. EUTEMPE-RX Eutempe-RX is a Network of excellent teaching centers, which provides dedicated courses at EQF level8. The course contents are driven by the "Guidelines of the MPE project" with the support of a Scientific Advisory Board and they consist in balanced e-learning (40 hours workload) done through a Multicampus Educational and Training platform and face-to-face sessions (40 hours workload). The educational tools and methods includes: • Creation of "groups of learners" and guided tasks prior to the face-to-face moments • Online communication & feedback between teachers and learners • Interactive self-assessment test • Up-to-date multimedia material • Solutions for practical training • Interactive exercises • Databases of Material [ABSTRACT FROM AUTHOR]

Development and application of a practical DQE protocol for routine use by medical physicists during assessment of digital radiography systems. J. McFadden, M. Donoghue, E House, B. Tuohy. Measurement of the Detective Quantum Efficiency (DQE) of a DR detector provides a more quantitative assessment of the imaging performance of a system in comparison to the very subjective assessments traditionally used by medical physicists “in the field”. Although commonly used by the system manufacturers, the method has yet to be widely incorporated into quality assurance (QA) protocols in Irish hospitals. We will report in this paper on the findings from a project which aimed to adapt the IEC-62220 industrial DQE standard for a clinical environment. Results from our studies on the influence of DQE software algorithm chosen, variations in image acquisition and processing methods will be presented and explored. Development of the technique involved a compromise between the Industry standard IEC method and the practical limitations of time and equipment availability experienced by medical physicists in the field. Following adaptation of the Industry standard DQE approach, a practical methodology, which can be applied to any general radiography DR detector, allows medical physicists in the field to incorporate DQE assessment in their annual DR system assessment. A number of problems and challenges encountered during the project will be explored and the salient findings will be presented. In conclusion, a novel adaptation of an industry standard DQE technique developed by our group is shown to be appropriate for use in a clinical environment. [ABSTRACT FROM AUTHOR]

Purpose This work reports our experience on MRI acoustic noise as acoustic experts as well as advisors for the local authority. The aims are. • the protection of people health as a state of complete physical, mental and social well-being of any person in the magnetic resonance practice • reducing possible distortions of competition • avoiding expensive protection actions after installation. Materials and methods In order to correctly assess the risk, a procedure has been adopted in accordance to: • Italian law and 89/391/EEC Safety and Health of Workers at Work Directive, • European Standards, literature data and our experience. E.g. if RMI site is planned in civil contest, the noise levels are to be referred to WHO values and, in Italy, to values of municipal regulation for protection from noise. For the activity of medical reporting and control room we consider quality levels recommended in EN ISO 11690–1-1996. In this paper, are specified the necessary data and the roles involved as manufacturer, RM site project planner, and physician. When data are insufficient, the procedure describes experimental sets with reference points (isocenter bore&laser cross&..), phantoms, sequences, condenser and optic microphones and protocol to obtain information.. Results At isocenter ear position (1.5T) SPL shows more then 110 dBA&dBC for some sequences. In some cases a surrounding activity had to be moved. To neglect the noise could cause annoying problems as operator/patient interferences and health effects for patient, worker and surrounding inhabitants. It’s possible to manage the risk choosing adequate site, technology, HW, reducing noise at source and/or adopting collective protection and finally passive and active ear protectors and PPE. A suitable measurement protocol can be useful to assess noise and to plan adequate protections when RM is by now working. Conclusions Acoustic noise has to be considered and assessed as one of the first steps in the MR site planning and activity. It can be reduced to appropriate level. Acoustic noise would be evaluated mandatorily also by competent authorities for the control of compliance of the RM implants for a formal green light. [ABSTRACT FROM AUTHOR]

Purpose Medical Physics is one of the first professions to develop and introduce e-Learning, what resulted in the first EU Award for education “Leonardo Da Vinci”, 2004 [1] . For about 20 years the profession developed many e-learning projects. These were pivotal for the double growth of the profession in this period. The presentation aims to give an overview of the progress so far and possible ways ahead, focussing on the expected global tripling of medical physicists in the next 20 years. Methods The paper presents briefly the e-learning methods used by some specific projects; the development process; the testing/implementation of e-learning in the profession. It also includes user feedback and views for the future implementation of e-learning in medical physics. Results The outcomes of the first main international e-learning projects include the first e-learning materials in the profession (which are also some of the first e-learning materials with ISBN in the world); the development of a system for assessment of such results (including the first e-learning conference in the profession); the development of the first e-Encyclopaedia of Medical Physics and associated with it Multilingual Dictionary of Terms (translated in 30 languages). Due to the excellent IT skills in the profession, many other e-learning activities have been and are being developed all over the world. These could be classified in three main categories: Building modules; Developing simulations; Implementing Course-management systems. The presentation will show sample e-learning projects from all these categories. Conclusions e-Learning has now a steady place in medical physics – this is imperative for a dynamic profession and needs to be supported at all levels. One of the main objectives of IOMP for the launch of the Educational/Professional Journal Medical Physics International was to provide a platform for exchange of expertise and ideas in the field of education, specifically e-learning. Our experience for more than 20 years shows that this is of great importance, as often the life of the e-learning products is short and these need quick and effective exploitation. [ABSTRACT FROM AUTHOR]

Purpose The radiation protection legislation requires patient dose surveys to be organized and diagnostic reference levels (DRLs) to be established and further used by radiology facilities for benchmarking and optimizing their local practice. To facilitate this process, an online data collection platform for national dose surveys in diagnostic and interventional radiology was created by the Ministry of Health. To report their data in absence of dose tracking software, the hospital staff needs to enter data manually through the platform interface. This paper presents a tool developed to speed up this process and reduce human errors. Methods and Materials A freeware application idRS was developed that constitutes electronic forms in Excel (Microsoft Corporation, USA) format with interactive functions written in Visual Basic for Applications (VBA). Its role is to gather needed data from a manually or automatically populated Excel table, and transfer them to the online platform. The interactive features include checking for technical errors in the data sample, guiding hints for users, automatic data transmission, automatic estimation of the typical (mean) dose of the sample and comparison of this value with the current national DRL and/or values published in the scientific literature. Results Separate versions for radiography, fluoroscopy and computed tomography were created. They were tested with 880 real patient dose data recorded in three X-ray departments, and previously submitted manually through the online platform. No difference was found between the calculated mean values from data sets transferred with idRS and previously reported. The results of testing the idRS with two different computer configurations found difference of less than 2 s in the transfer time for 20 patients per procedure, which varied between 7 s for radiography and 20.7 s for multi-phase CT. Conclusion The idRS application significantly simplified and improved the process of submitting patient data to the online platform. It is expected that this will encourage more hospitals to contribute to the national dose data collection and for using the platform for establishing their local typical doses. [ABSTRACT FROM AUTHOR]

Purpose The protocol for quality control of CBCT devices was produced as consensus among active MPEs of EFOMP, ESTRO and IAEA. It is available on-line since September 2017. In the beginning of 2018 we published an update including an appendix on patient dosimetry by EURADOS, comments by the German institute of standards (DIN) and remarks by users from countries that were not involved in the first edition, such as Austria, Costa Rica and Australia. This contribution gives a general overview of the guideline including insights about this recent update. Methods The guideline focuses on the measurement of objective image quality parameters and radiation output from any kind of CBCT device, including applications in dental radiology, C-arms and guidance systems in radiotherapy. Indications to use commercial or non-commercial phantoms and software are given, as well as to use ionization chambers or solid state dosemeters. The new EURADOS appendix includes an extensive review of patient dose data from recent research papers, organized by application and dose indicators: CTDI, DAP, effective dose, entrance surface dose, CTDIw, absorbed dose, D1-D2 and air kerma. The DIN has reviewed the details of the standards 6868–161 and 6868–15 for acceptance and constancy tests in dental CBCT. Individual comments have helped to clarify the measurements of radiation output and the methods to measure the modulation transfer function. Some colleagues have stressed the informative value of the appendices. Results The comments received were reviewed by the authors of the corresponding sections and discussed by the group in virtual meetings before being published as an update. The mentioned additions are meant to keep the document alive. They respond to questions raised by physicists that are starting to use the protocol inside and outside Europe. Conclusions The first presentation in the ECMP in Athens was followed by international presentations at ESTRO, ECR, IOMP and IRPA and national presentations in Italy, Spain, UK, Germany and other countries. Thanks to these voluntary efforts, physicists around the world are using and improving the document together. We also welcome your participation in this session and your feedback. [ABSTRACT FROM AUTHOR]

There are many papers focused on secondary neutrons by calculation or measurement in high-energy radiotherapy fields [1,2] . Monte Carlo calculation is easy to acquire the three-dimensional spatial distribution of the neutrons and is considered to be particularly useful tool for evaluating the “on-axis” of the primary radiotherapy beam. In this study, calculations were performed for practical application of treatment planning that can take three-dimensional neutron dose into account by combining with new treatment planning system “Tsukuba-Plan” currently developed by University of Tsukuba. The incident radiotherapy beams were X-rays and “passive” particle beams (proton beam, carbon-ion beam). Particle and Heavy Ion Transport code System (PHITS) [3] was used as Monte Carlo code. We constructed calculation geometries that reproduces the actual beam delivery systems of these radiotherapy fields as precisely as possible, and confirmed consistency by comparing with measured percentage depth absorbed dose. The neutron doses and energy spectrums of “on-axis” and “off-axis” in homogeneous water phantom were calculated by irradiating each primary beams. Calculated neutron doses were compared with some published literatures. As next step, we used the Tsukuba-Plan to obtain the three-dimensional neutron dose distributions in human-shaped phantom in case of irradiating clinical beams with patient-specific devices such as bolus and collimators. We achieved a relative comparison of the secondary neutron doses and energy spectrums at “on-axis” and “off-axis” of each incident beams by using PHITS code. Additionally, the three-dimensional neutron dose distributions in the human-shaped phantom by each beams were obtained by combining the Tsukuba-Plan. In the future, this function can be used for various evaluation of the secondary neutrons in radiotherapy fields under individualized irradiation conditions. [ABSTRACT FROM AUTHOR]

Introduction Reducing treatment duration in proton therapy is one of the key factor to increase the number of patient treated per day. To overcome this issue, we have developed novels haptic manual guidance control implemented on the patient positioning robot (Orion PT) to be used during the pre-positioning phase by the paramedical assistant. These manual control modes allow the paramedical assistant to be close to the patient while reducing the time for the pre-positioning setup. The four manual control modes of the robot are compared with a generic reach-and-point trajectory. Methods The main objective of this article is to compare intuitiveness of the four following manual guidance modes on the proton therapy robot already presented in [1] : - TeachPendant remote sensor with one button per Cartesian axis (with a total of 6). This is the reference control mode used in actual radio/proton therapy treatment room. - U bar haptic device located under the couch top and mounted on Force/Torque sensor to follow paramedical assistant intention in measuring applied force. This control mode was previously presented in [2] . - Couch top comanipulation mode. Paramedical assistant is able to move the couch top directly in applying force upon it. A F/T sensor located between couch top and robot end-effector measure operator intentions and move the couch top accordingly. The benefits of the haptic guidance compared to the previous one is the ability for the paramedical assistant to manipulate the robot directly from the couch top from any location around it, increasing intuitiveness. - 3D haptic joystick with translations as well as rotations placed on the couch top. The robot move as the same way as the 3D joystick does. A comparison between those haptic control modes will be done using a reference trajectory and the following criterion will be used to assess the intuitiveness of the proposed methods: - Movement duration to reach target. - Mean error between real and reference trajectory. - Learning curve. Results By now, the fourth haptic devices can be used with the robot and have been successfully tested. Several quantitative tests show intuitiveness improvement with U-bar haptic device compared to traditional control with teachPendant. Some qualitative tests will be carry out to measure the benefit of the three manual haptic control of the robot previously described. Conclusions This paper shows three novels haptic device to manually control a proton therapy robot during pre-positioning phase performed by paramedical assistant. Qualitative tests shows benefit of one of the proposed methods and quantitative tests will be executed soon. [ABSTRACT FROM AUTHOR]

Measurement of staff radiation exposure to ultraviolet (UV) radiation in Dermatology and other Departments currently relies on measurements using fixed detecting equipment. Although staff do not usually receive direct UV exposure, they may be exposed through scattered UV radiation from hand & foot units, moveable panels or whole body irradiation units. The paper aims to investigate whether the 'Sunbeat', a novel ambulant UV monitor developed for measurement of personal solar UV exposure, could be used to measure clinical staff UV exposure. The Sunbeat device was compared against a local International Light IL1400 meter calibrated to national standards for unweighted irradiance using banks of both R-UVA and Philips TL01 narrow-band UVB fluorescent tubes with different levels of irradiance for both UVA and UVB under fixed geometry. Simultaneous adjacent measurements were then made of scattered UVA and UVB levels with the Sunbeat device and the local calibrated meter. Individual correction factors were then applied to the local calibrated meter readings to produce eythemally effective irradiance. When compared to the local calibrated meter, the Sunbeat device exhibited a linear response for both the measurements in the fixed geometry and ambulant scattered UV measurements. The Sunbeat device could measure scattered UV levels down to approximately 0.1 μ W cm−2 erythemally effective irradiance for both UVA and TL01 UVB. The Sunbeat device has the potential to be used as a UV dosimeter for clinical staff. This may aid the demonstration of compliance with national regulations made under the EU Artificial Optical Radiations Directive. The Authors do not have any disclosures that may bias their presentation. [ABSTRACT FROM AUTHOR]

This paper discusses brachytherapy treatment and individual applicators suitable for difficult to reach locations of superficial malignant lesions. Technique for manufacturing an individual applicator and clinical examples of its use for various locations of cancer are presented. [ABSTRACT FROM AUTHOR]

Complex radiotherapy treatments require accurate quality assurance programs, in order to prevent errors that can affect patient treatment. Recently several very serious incidents have been reported. Transit EPID in vivo dosimetry has been shown able to intercept and correct many of these errors. Aim of this paper is to furnish an overview about state-of-art transit EPID dosimetry softwares. The basic functionality, clinical implementation and results of main softwares are reviewed. Systems showing dosimetric results after the first fraction of treatment (quasi real time), and during the irradiation (real time) have been included in this review. [ABSTRACT FROM AUTHOR]

Purpose Italian laws are very restrictive in terms of release and exemption quantities in case of waste contaminated by radioactive isotopes. This study focuses on the characterization of a 18 MV Elekta Precise Linear Accelerator head that have been in clinical use since two days before its dismantling to make space to a new "state of the art" machine. Methods Dismantling have been carried out by an Italian specialized company, each part of the machine have been first measured with a high efficiency α, β, γ contamination monitor equipped with ZnS:Ag detector and a portable γ-ray spectrometer (NaI(Tl)). Activated parts have been subsequently measured with a low background, high reliability and high definition spectrometric chain (DSA-1000 and Genie 2000 software, Canberra), with an electric cooled High Purity Germanium detector (HPGe) with 20% relative efficiency (GX2018 detector and Cryo-Pulse5 plus cooler, Canberra). Energy, FWHM and efficiency calibration have been performed with a multigamma Marinelli source in the range 59 keV (241 Am) – 1836 keV (88Y). Efficiency curves for different geometries have been calculated with a 3D model of the detector-sample system and Montecarlo (MC) method by ISOCS/LabSOCS efficiency software (Canberra). Results 57Co, 58Co, 60Co, 54Mn have been among the more frequent radioisotopes found. However short lived nuclides (eg. 122Sb, 187W, 57Ni) were present as well. Conclusions Activation of long lived radionuclides was confirmed as previously reported in published paper [1,2] ; short lived radionuclides were detected as well. Waiting for full decay of short lived radioisotopes could allow to minimize the amount of radioactive waste. [ABSTRACT FROM AUTHOR]

Purpose Dual-energy contrast-enhanced spectral mammography (CESM) has emerged as a potential new option for breast cancer staging. This imaging technique allows acquisition of multiple views of both breasts after a single injection of iodinated Contrast Medium (CM). It based on the fact that the CM injected will have different uptake path between hypervascularized breast lesions and background parenchyma. The aim of this paper is to evaluate the performance of identifying and characterizing the breast lesions, costs and comfort of patients of a supervision CESM single-step path with respect to a traditional double-step path mammography and MRI. Methods We collected data on 46 patients who performed CESM: we have selected a subsample that also performed mammography in tomosynthesis and MRI. A total of 33 lesions have been identified by histological examination (28 malignant and 5 benign). The findings of all the techniques have been submitted to double blind check by two radiologists. The test was performed on 2D synthetic images of tomosynthesis and confirmed in low-energy images of CESM as reported in literature [1]. We have performed a statistical analysis of the diagnostic performances of each method in order to estimate the efficiency of the proposed diagnostic path with the only CESM technique with respect to the traditional path. Results This study have shown consistent results in terms of sensitivity (over 90%) and between paths. The total costs of CESM alone were lower than the combination of digital mammography and MRI with CM, and between the different methods, while the greater discomfort was reported by patients undergoing MRI. Conclusions The comparison between the methods has underlined the validity of the CESM supervision model both as morphological examination with respect to traditional mammography, and as dynamic examination with respect to MRI, according to the literature. In addition, CESM is more tolerated by patients than MRI and less expensive than the traditional paths. [ABSTRACT FROM AUTHOR]

Purpose The aim of this paper is to develop an operator independent method for biological tumour volume (BTV) delineation from Positron Emission Tomography (PET) images. BTV delineation is challenging because of the low spatial resolution and high noise level in PET images. In addition, BTV varies substantially depending on the method used to segment. Manual delineation is widely-used, but it is strongly user dependent. Methods The proposed method starts with the automatic identification of the PET slice with maximum Standardized Uptake Value (SUV). Then, a user- independent mask is obtained by a rough pre-segmentation step and it is used to perform the local active contour segmentation on the next slices. When the proposed method finds a slice where the mean SUV on the interior of the delineation contour is greater or equal than the mean SUV on the exterior of the delineation contour, the segmentation is automatically stopped. The algorithm is evaluated on four datasets of synthetic lesions considering different ratios between lesion and background radioactivity concentrations. In this way, the actual lesion volumes are known and the segmentation algorithm is evaluated under different contrast ratio scenarios. In addition, BTVs of 25 patient studies have been manually delineated and compared to the proposed method in order to assess its applicability in a clinical environment. Results In phantom experiments, dice similarity coefficient (DSC) rate and true positive volume fraction (TPVF) rate greater than 90% were observed in synthetic lesions with a diameter greater than 17 mm. In clinical cases, TPVF and DSC were 91.00 ± 7.33% and 85.98 ± 3.40%, respectively. Conclusion Our method produces accurate segmentation results in phantom studies. In addition, it is feasible in clinical context and shows good accuracy in realistic conditions, reducing any user interaction. [ABSTRACT FROM AUTHOR]

Abstract Purpose This work is part of a larger cohort study aimed at investigating the long term effects of exposure to manganese [1]. In this study we set up a protocol for brain fast T1 mapping and segmentation of subcortical tissues, in particular globus pallidus (GP), that is reported to be a target tissue for manganese deposition in brain. Methods The variable flip angle model was used for T1 mapping. Acquisition protocol, set up on a 3T Siemens Skyra MR system, includes 10 RF spoiled 3D gradient echoes (VIBE) with flip angles from 2° to 30° and a reduced scanned volume to cover GP in the shortest possible time, an extra 30° VIBE covering the whole brain (WB- VIBE), two fast acquisitions with different TEs for B1 map calculation, used to correct nominal flip angles, and a 3D-MPRAGE acquisition of the whole brain with the same WB-WIBE geometry. T1 and error maps were calculated offline with a bespoke Matlab script, checking accuracy with calibrated gels. The most efficient pipeline for post-processing, shown in Fig. 1, is as follows: T1 map calculation of the reduced volume, and zero padding of the missing slices to get the same WB-VIBE volume (WB-T1MAP); 3D-MPRAGE and WB-T1MAP coregistration using the WB-VIBE to 3D transformation matrix (WB-T1MAP-COR); GP automatic segmentation of the 3D-MPRAGE and, with the output mask, GP statistics calculation of the WB-T1MAP-COR. In order to cancel possible partial volume effects, segmented regions were eroded by 1 pixels and T1 results were compared. The protocol was checked on a group of 10 adolescents that were exposed to Mn during childhood. Results T1 accuracy was 4.3% (median) and within 13.8% (interquartile distance). GP-T1 average values were 1314,65 ms and 1302,92 ms after erosion, close to the values reported in other papers, with a coefficient of variation respectively decreased from 6.8%, to 5.6%. Conclusions We set up a fast and automated T1 mapping protocol with good accuracy and optimised data variability in vivo. [ABSTRACT FROM AUTHOR]

Abstract Purpose In Vivo EPID dosimetry, is a time-consuming procedure. This paper reports a time workload analysis of SOFTDISO software (SW) (Best Medical Italy) obtained in our center. Methods the time workload analysis was subdivided into two phases: the first regard pre-clinical mounting in particular the creation of communication DICOM nodes ( t links) , the SW commissioning time ( t commissioning) and the radiology technician training time ( t training) ; the second refer to clinical routine. This last phase was divided in four steps: single patient's loading times, t load , (import patient from TPS to SW, t TPS-SW , and from TPS to EPID management device, t TPS - EPID) ; single patient's daily synchronization time on SW, t synchro ; single patient's setting time, t set-up ; time of troubles, t troubles . In our center the TPS was Pinnacle 9.10 (Philips) and EPID device was IViewGT (Elekta). Results The pre-clinical phase required about three weeks where a multi-disciplinary team (medical physicist, product specialist and system administrator) has worked to interface all devices, the medical physicist has performed the SW commissioning measure and along with the product specialist they trained the staff. For a single patient by the clinical times shows in Table 1 we can calculate the daily time, t daily , equal to (240 ± 135) s and the insertion time, t load , equal to (180 ± 30) s. This time analysis was performed overall 30 patient. The daily workload was estimated from 10 of 20 patients treated per day who undergo to in vivo dosimetry checks and was equal to 45 min. Conclusions After a month a medium sized radiotherapy center gets these results with a dedicated medical physicist and a radiology technician. Additional clinical time is required to discuss the out of tolerance value provided by the SW. This time was estimated in 1 h per week. [ABSTRACT FROM AUTHOR]

Purpose Short-lived beta-emitting radionuclides, such as 90Y, start to be commonly used in Nuclear Medicine (NM) for Molecular Radiotherapy (MRT). The instruments, such as Ionization Chambers (ICs), typically used in the NM departments for measuring the activity of radiopharmaceuticals need to be calibrated in order to meet the demands of the European Pharmacopoeia [1]. The OPBG IC was then calibrated for the 90Y by using the ENEA-INMRI portable TDCR counter [2]. Methods The 90 YCl 3 solution was kindly provided by Sirtex company. A set of 6 sources (2 in 10 mL UG + 20 mL glass vial, 2 in 10 mL H 2 O + plastic vial, 2 in 10 mL H 2 O + 20 mL glass vial with 20 mg and 40 mg of radioactive in each one) and 1 source in the OPBG IC vial geometry were prepared directly at OPBG to be measured by TDCR and IC devices. Results The achieved results show that, in the typical operative conditions of a hospital structure, the uncertainties in determining the IC calibration factor are less equal to 2%. Conclusions The paper highlights how the TDCR-Cherenkov technique, developed at ENEA-INMRI, allows to calibrate on site an IC in use at a Hospital structure. In particular, this technique turns out to be more practical, because the sources to be characterized in activity, for the IC calibration, can be prepared directly in water. The whole work was performed in the framework of the project "Metrology for clinical implementation of dosimetry in Molecular Radiotherapy" (MRTDosimetry) funded by the European Metrology Program for Innovation and Research (EMPIR) [3]. [ABSTRACT FROM AUTHOR]

Purpose Contrast-Enhanced Spectral Mammography (CESM) allows the acquisition of low- and high-energy digital mammograms with Dual-Energy technique after a single injection of iodinated contrast medium (CM) obtaining the production of recombined mammographic images [1,2]. The aim of this paper is to characterize ROI and measure the gray-level parenchymal background in order to improve the lesion detection in CESM. Methods We have selected 42 patients positive to the methodic for the presence of at least one findings after histological examination.We have evaluated 65 lesions (52 malignant and 13 benign) from 0.5 to 13.5 cm. Primary and secondary (if present) lesions have been identified and their diameters have been measured in axial projection. Regions including the parenchymal background and the non-contrasted background were also marked in both low-energy and recombined images.For each region the statistical parameters of gray levels were recorded by CESM instrumentation and have been elaborated by multivariate statistics and machine learning techniques in order to characterize each region and define a background intensity indicator, not yet defined objectively. Results The analysis on our available dataset seems to underline significant differences between ROIs with lesions and regions marked on the parenchymal background with respect to the coefficient of variation, i.e. standard deviation of the gray levels of the marked area compared to the mean value of the same) in recombined images.We have found an increase of the coefficient of ROIs greater than 20% with respect to the coefficient of the regions marked on parenchymal background in 57 lesions. Conclusions As preliminary results, an indicator to detect the parenchymal background can be identified as the coefficient of variation. Data collection is currently ongoing because a more massive data sample will be useful to increase the sensitivity in the lesion detection by CESM device, even in patients with a medium-high value of background. [ABSTRACT FROM AUTHOR]

On-board imaging fluoroscopy is used for localisation of the target immediately prior to external beam radiotherapy. The feature is clinically used for lung stereotactic ablative radiotherapy involving a moving target and high dose per fraction. Use of fluoroscopy is clearly justified, allowing verification that the target is within the field over its range of motion, ensuring the tumour is not under-treated and there is not excessive dose to normal tissue. Commissioning the fluoroscopy features on Varian Clinacs and Varian Truebeams demonstrated that systems are not optimal at installation. The ability to adjust the automatic brightness control settings is not readily available and access required extensive discussions with the manufacturer. The TrueBeam linear accelerator had additional dose reduction features not available on the Clinac. Such features available in clinical mode included the ability to adjust pulse rate settings and add additional titanium filtration This paper will detail the potential for significant patient dose reduction (35 mGy/min to 16 mGy/min Clinac, 75 mGy/min to 8 mGy/min Truebeam) without a clinically significant reduction in image quality. The doses post optimisation are below what would be expected from an image intensifier and slightly higher than what would be typical for a modern flat-panel interventional system. The dose comparisons are made to interventional systems due to the lack of published data in radiotherapy systems. Historically the focus has been on the considerably higher radiotherapy dose, but recent developments and increased use of imaging in therapy has seen increased attention to imaging doses. [ABSTRACT FROM AUTHOR]

Three-dimensional dosimeters are of great interest in a progressive radiotherapy facility utilising complex and advanced treatment techniques such as high dose rate dynamic stereotactic ablative radiotherapy (SABR). In our Centre we recently introduced 6 MV flattening filter free (FFF) dynamic conformal arc (DCAT) and volumetric arc therapy (VMAT) as treatment options for our lung patients using 4D-IGRT on the Elekta platform. Treatments of this nature however, are difficult and complex to validate and mainstream quality assurance tools are often limited in their ability to satisfy clinical demands. Clinical requirements dictate that for short fractionation high dose regimes such as SABR that the geometric and dosimetric parameters of a plan are well known and within tight tolerances. Three-dimensional polymer gel dosimeters offer significant advantages for encapsulating and validating steep 3D dose distributions of this complexity. This paper describes clinical studies of the normoxic PAG gel dosimeter (Venning et al., 2005) with MRI readout for validation of complex FFF treatment delivery techniques. Patient plans were analysed using 3D gel dosimetry techniques and compared against standard clinical dosimetry QA tools. There are numerous challenges involved when operating a clinical gel dosimetry service including high dose per fraction for SABR leading to dosimeter saturation, MRI access, expertise and time. These issues will be covered in the presentation. [ABSTRACT FROM AUTHOR]

Purpose The apparent simplicity of individualized dosimetry in radioembolization with 90 Y microspheres has pushed many centres to collect data. As a result, dosimetric papers and software advances obtained in 10 years are much more than those produced in 70 years of metabolic therapy with other radiopharmaceuticals. Aim of this lecture is to enlighten the limits of the present planning methodology and to remark the importance of the clinical results obtained. Methods Dosimetric treatment planning is based on 99m Tc albumin macroaggregate (MAA) SPECT/CT. Scatter correction is mandatory. The patient relative calibration method makes a correspondence between total 99m Tc SPECT counts and the intended 90 Y activity, using each patient as a calibration phantom for himself. Local energy deposition method more accurately represents the true activity distribution than convolution methods, but not in lung, where convolution is necessary. Breathing motion is a problem both in liver SPECT and CT. In hepatocarcinoma (HCC), segmentation of large lesions showing a necrotic core raise the problem of SPECT versus CT based segmentation. Infiltrative lesions can be evidenced with MRI only, but the two compartment model cannot be applied. Voxel dosimetry is limited by SPECT noise, which acts as intrinsic uncertainty principle. The heaviest source of uncertainty is the discrepancy between MAA and actual 90 Y microsphere biodistribution. Results Despite the above mentioned limits, dose response correlations have been reported by almost all researchers, with both kind of microspheres and for several kind of disease (HCC, colorectal metastases). Dose toxicity correlation has been less studied but it has been reported. The most striking results, never reported previously for any other therapeutic agents, is that at a multivariate analysis, lesion absorbed dose is the only variable associated with overall survival. Conclusions While limitations of the treatment planning methodology result in a poor prognostic value on some individual patient, we have strong indications of improvements of clinical outcome in terms of general parameters of the treated population (response and toxicity rate, progression free and overall survival). [ABSTRACT FROM AUTHOR]

Purpose The reduction in dose limit for the lens of the eye has focussed attention on methods for protecting the eyes of interventional radiologists and cardiologists. The need to obtain reliable dose measurements while protecting the eye, sometimes by using protective eyewear is proving a particular issue. This paper will explore some of the factors and consider options available. Methods The International Commission on Radiological Protection are finalising a report on “Occupational Radiological Protection in Interventional Procedures” to provide guidance on some of the issues and the main conclusions relating to eye dose will be presented. In addition results from studies involving the investigation of shielding provided by different protection methods, including results from practical studies and computer simulations, will be reviewed. Different options for measurement of eye doses will be considered. Results Ceiling suspended screens provide effective shielding for the whole head and if used efficiently they can reduce eye doses to levels well below the dose limit. However, this requires the operator to make adjustments to the screen whenever the patient couch or X-ray tube position are changed. Protective eyewear provides additional shielding, but its use complicates measurement of dose to the eye lens. Factors relating to the effectiveness of eyewear of varying design will be considered, and flaws in current models highlighted. When lead glasses are worn, the dose to the eye lens would ideally be measured by a dosimeter placed on the skin, near to the eye, and behind the lead glasses. Dosemeters could be attached to the glasses, but this has its own problems and if located in certain positions, dosemeters could significantly underestimate doses to the eyes. Alternatively dosemeters could be worn on the side of the head or forehead, but then a correction factor would need to be applied to obtain the actual dose to the eye. Conclusions It should be possible to keep doses to the eyes for interventional radiologists and cardiologists below the dose limit with effective use of protective devices. However, eye dosimetry will be problematic and users need to understand the problem if this is to be accomplished. [ABSTRACT FROM AUTHOR]

Purpose To report the state of the art of biological-based automated inverse planning (BBAIP) strategies and highlight future perspectives. Methods A Pubmed search has been conducted to identify the commercial tools for BBAIP. Crucial/main features of the currently available tools have been identified from the retrieved papers/manuals and have been compared in order to evaluate their applicability in the clinic. In particular, for each software features such as the type of systems (commercial TPS or research tool), the available optimization strategies (physical and biological), the used radiobiological model or mathematical formalism, the identified parameters and endpoint (when appropriate), optimization efficiency, etc. have been extracted. Results A table reporting the available BBAIP tools, the optimization strategies (physical and biological), the used radiobiological model or mathematical formalism, the identified parameters and endpoint (when appropriate), the optimization efficiency, etc. has been extracted for each software. A critical revision of commercial/research tools has been conducted also taking into consideration their application in the clinical routine, summarizing the analysis in a table. The potential issues concerning the used model and parameters have been discussed. The parameter sensitivity represents a potential limitation of this approach. Starting from the identified systems, transition to spatio-temporal non-uniform target dose distributions represents a major paradigm shift in treatment planning. Conclusions BBAIP have great potential in terms of efficiency and speed of calculation and can be implemented in clinical practice to meet the needs of a radiotherapy department using terms and languages reflecting clinical goals of radiotherapy. However, their use is still limited to few centers and could be increased by improving confidence on the radiobiological models that are implicitly applied in clinical practice. Developments in our understanding of advantages and limitations of existing dose-response models could allow the incorporation of biological concepts into a routine treatment planning process. [ABSTRACT FROM AUTHOR]

Purpose This paper presents a complete and validated computer-based system dedicated to X-ray phase contrast breast imaging research. The system comprises three main modules: (a) a module for generation of computational breast models, (b) a module for generation of phase-contrast X-ray images from computational phantoms in 2D and 3D acquisition setup, and (c) a module for image reconstruction. Methods The module for computational breast models is based on the BreastSimulator tool, used to generate breast models of various sizes and to compress them to a desired thickness. The module for the generation of phase-contrast images is used to model the image acquisition geometry and formation of X-ray images. The image reconstruction is done with a software tool, based on an in–house built reconstruction techniques class library, which is a dedicated object-oriented library for X-ray based applications. The capability of this system to correctly calculate phase-contrast tomographic images was tested by comparing simulated versus experimental images obtained from anthropomorphic breast phantoms. Three anthropomorphic computational breast phantoms were designed from white and grey resin by using the available stereolithography 3D printer. Experimental projection images were acquired and simulated images were generated, considering a breast tomosynthesis setup. Experiments were conducted at beamline ID17, ESRF. Simulations replicated the experimental setup. Images in a tomosynthesis mode were generated and tomograms were calculated by using the reconstruction module. Results Results show very good visual agreement between simulated and experimentally obtained tomosynthesis images. In addition, selected tomosynthesis images from the physical and computational breast phantoms were quantitatively evaluated for set of imaging parameters such as skewness, kurtosis, the power-law exponent, β , of the power spectrum and fractal dimension. Analysis and the comparison of these parameters between simulated and experimental images also show a very good coincidence. Conclusions The platform is currently used in the process of development of a dedicated breast phantom for phase contrast imaging techniques. The system will be a valuable tool in studying new X-ray imaging techniques based on phase contrast, such as phase contrast tomosynthesis and CT. [ABSTRACT FROM AUTHOR]