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Background: The use of Computed Tomography (CT) imaging data to create 3D printable patient-specific devices for radiation oncology purposes is already well established in the literature and has shown to have superior conformity than conventional methods. Using non-ionizing radiation imaging techniques such as photogrammetry or laser scanners in-lieu of a CT scanner presents many desirable benefits including reduced imaging dose and fabrication of the device can be completed prior to simulation. With recent advancements in smartphone-based technology, photographic and LiDAR-based technologies are more readily available than ever before and to a high level of quality. As a result, these non-ionizing radiation imaging methods are now able to generate patient-specific devices that can be acceptable for clinical use., Purpose: In this work, we aim to determine if smartphones can be used by radiation oncologists or other radiation oncology staff to generate bolus or brachytherapy surface moulds instead of conventional CT with equivalent or comparable accuracy., Methods: This work involved two separate studies: a phantom and participant study. For the phantom study, a RANDO anthropomorphic phantom (limited to the nose region) was used to generate 3D models based on three different imaging techniques: conventional CT, photogrammetry & LiDAR which were both acquired on a smartphone. Virtual boli were designed in Blender and 3D printed from PLA plastic material. The conformity of each printed boli was assessed by measuring the air gap volume and approximate thickness between the phantom & bolus acquired together on a CT. For the participant study, photographs, and a LiDAR scan of four volunteers were captured using an iPhone 13 Pro™ to assess their feasibility for generating human models. Each virtual 3D model was visually assessed to identify any issues in their reconstruction. The LiDAR models were registered to the photogrammetry models where a distance to agreement analysis was performed to assess their level of similarity. Additionally, a 3D virtual bolus was designed and printed using ABS material from all models to assess their conformity onto the participants skin surface using a verbal feedback method., Results: The photogrammetry derived bolus showed comparable conformity to the CT derived bolus while the LiDAR derived bolus showed poorer conformity as shown by their respective air gap volume and thickness measurements. The reconstruction quality of both the photogrammetry and LiDAR models of the volunteers was inadequate in regions of facial hair and occlusion, which may lead to clinically unacceptable patient-specific device that are created from these areas. All participants found the photogrammetry 3D printed bolus to conform to their nose region with minimal room to move while three of the four participants found the LiDAR was acceptable and could be positioned comfortably over their entire nose., Conclusions: Smartphone-based photogrammetry and LiDAR software show great potential for future use in generating 3D reference models for radiation oncology purposes. Further investigations into whether they can be used to fabricate clinically acceptable patient-specific devices on a larger and more diverse cohort of participants and anatomical locations is required for a thorough validation of their clinical usefulness., (© 2024 The Authors. Medical Physics published by Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine.)

Radiation therapy (RT) continues to play an important role in the treatment of cancer. Adaptive RT (ART) is a novel method through which RT treatments are evolving. With the ART approach, computed tomography or magnetic resonance (MR) images are obtained as part of the treatment delivery process. This enables the adaptation of the irradiated volume to account for changes in organ and/or tumor position, movement, size, or shape that may occur over the course of treatment. The advantages and challenges of ART maybe somewhat abstract to oncologists and clinicians outside of the specialty of radiation oncology. ART is positioned to affect many different types of cancer. There is a wide spectrum of hypothesized benefits, from small toxicity improvements to meaningful gains in overall survival. The use and application of this novel technology should be understood by the oncologic community at large, such that it can be appropriately contextualized within the landscape of cancer therapies. Likewise, the need to test these advances is pressing. MR-guided ART (MRgART) is an emerging, extended modality of ART that expands upon and further advances the capabilities of ART. MRgART presents unique opportunities to iteratively improve adaptive image guidance. However, although the MRgART adaptive process advances ART to previously unattained levels, it can be more expensive, time-consuming, and complex. In this review, the authors present an overview for clinicians describing the process of ART and specifically MRgART., (© 2021 The Authors. CA: A Cancer Journal for Clinicians published by Wiley Periodicals LLC on behalf of American Cancer Society.)

Introduction: The Asia-Pacific Special Interest Group (APSIG) was formed in 2009 by the Australian College of Physical Scientists and Engineers in Medicine (ACPSEM) to support radiation oncology services in low-to-middle income countries in our region. In 2017, APSIG moved to the ACPSEM's charity, the Better Healthcare Technology (BHT) Foundation, enabling improvement in fundraising, marketing and partnerships with like-minded organizations., Methods: APSIG's main activity is to recruit certified medical physicists as volunteers to train local staff in countries such as Vietnam, Cambodia, Myanmar and Mongolia. APSIG also supports remote mentoring, coordinates the delivery of donated radiotherapy equipment, and brings Asia-Pacific medical physicists to Australia and New Zealand for conferences and hospital training., Results: The number of APSIG volunteer assignments has been steadily increasing over the last decade. Challenges include the limited number of ACPSEM certified medical physics volunteers, the limited opportunities to train the local physicists due to their heavy workloads, and language barriers. The COVID-19 pandemic has halted volunteer assignments for now but a range of alternative means of assistance such as webinars, online tutorials and virtual meetings are planned to continue APSIG's activities., Conclusion: APSIG will continue to provide a support service to radiation oncology staff in the Asia-Pacific region. APSIG and the BHT Foundation's work promotes quality health care by supporting medical physicists in Asia-Pacific countries and championing better radiotherapy technology access and treatment knowledge sharing., (© 2021 The Royal Australian and New Zealand College of Radiologists.)

Background: Despite the pivotal role of radiotherapy in oncology, the provision of radiation treatments remains inadequate in many areas of the world. The present report is an assessment conducted among Radiation Oncology centers of Veneto region with the aim to collect information concerning radiotherapy assets and technological equipment availability., Methods: Data concerning Veneto Radiation Oncology departments about radiotherapy activities, number of treatments, techniques used and radiotherapy machines available were collected. The reference time period was 2018. Reimbursement system databases and business intelligence systems were used. Extra-regional attraction and migration were evaluated. When available, data were compared to previous years., Results: Veneto in 2018 was endowed with 1 megavolt unit for about 153,000 inhabitants. The number of megavolt machines per million inhabitants resulted to be 6.72. In 51% of radiotherapy treatments, intensity-modulated techniques were performed. Six percent of treatments were administered to extra-regional patients., Conclusion: Radiotherapy assets and equipment in Veneto seem to be appropriate to standard requests in terms of availability and technology.

Purpose: Microbeam radiation therapy is a preclinical concept in radiation oncology. It spares normal tissue more effectively than conventional radiation therapy at equal tumor control. The radiation field consists of peak regions with doses of several hundred gray, whereas doses between the peaks (valleys) are below the tissue tolerance level. Widths and distances of the beams are in the submillimeter range for microbeam radiation therapy. A similar alternative concept with beam widths and distances in the millimeter range is presented by minibeam radiation therapy. Although both methods were developed at large synchrotron facilities, compact alternative sources have been proposed recently., Methods and Materials: A small-animal irradiator was fitted with a special 3-layered collimator that is used for preclinical research and produces microbeams of flexible width of up to 100 μm. Film dosimetry provided measurements of the dose distributions and was compared with Monte Carlo dose predictions. Moreover, the micronucleus assay in Chinese hamster CHO-K1 cells was used as a biological dosimeter. The focal spot size and beam emission angle of the x-ray tube were modified to optimize peak dose rate, peak-to-valley dose ratio (PVDR), beam shape, and field homogeneity. An equivalent collimator with slit widths of up to 500 μm produced minibeams and allowed for comparison of microbeam and minibeam field characteristics., Results: The setup achieved peak entrance dose rates of 8 Gy/min and PVDRs >30 for microbeams. Agreement between Monte Carlo simulations and film dosimetry is generally better for larger beam widths; qualitative measurements validated Monte Carlo predicted results. A smaller focal spot enhances PVDRs and reduces beam penumbras but substantially reduces the dose rate. A reduction of the beam emission angle improves the PVDR, beam penumbras, and dose rate without impairing field homogeneity. Minibeams showed similar field characteristics compared with microbeams at the same ratio of beam width and distance but had better agreement with simulations., Conclusion: The developed setup is already in use for in vitro experiments and soon for in vivo irradiations. Deviations between Monte Carlo simulations and film dosimetry are attributed to scattering at the collimator surface and manufacturing inaccuracies and are a matter of ongoing research., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Application of the most advanced radiation technologies of brachytherapy featuring the high dose ratesources i.e. 60Co and 192Ir within contemporary management protocols for gynecological cancer provides maximum dosedistribution in the clinical target along with minimal radiation exposure on surrounding organs and tissues. It involvesirradiation of large spaces with delivery of high therapeutic doses at the tolerance bound of «critical» organs (bladder,rectum) and tissues. Thus minimization of the early and late radiation complications, life span extent and quality oflife increase remain just the issues in contemporary radiation oncology requiring therefore the elaboration of radiobiological criteria along with substantiation of physiсо-engineering properties of the radiation sources. Taking intoaccount the basic radiobiological patterns will ensure a definitive further progress in the field of radiation oncology., Objective: to study and compare the biological effects of 192Ir with the effects of the reference gamma radiation 60Coand increase the effectiveness of brachytherapy using a 192Ir source., Materials and Methods: Radiobiological dosimetry on the basis of a test system of peripheral blood lymphocytesfrom the gynecological cancer patients with subsequent cytogenetic analysis of radiation-induced chromosomeaberrations was performed to study and compare the biological effects of 192Ir and reference 60Со γ-radiation, and toenhance the efficiency of 192Ir brachytherapy., Results: Radiation markers, i.e. dicentric chromosomes with an accompanying paired fragment prevailed in thespectrum of radiation-induced damage. Variability of individual cytogenetic parameters of peripheral lymphocytesupon the first fraction of irradiation at the same dose of 5 Gy indicated an individual sensitivity of patients to the192Ir γ-irradiation. Comprehensive conservative treatment with adjuvant radiotherapy was applied to the patients(n = 98) having got secondary vaginal cancer stage II-III, T2-3N0-1M0. The high dose-rate (HDR) brachytherapy using 192Ir radiation sources was applied in the main study group (n = 37), HDR brachytherapy using 60Co radiation sourceswas applied in the control group (n = 35)., Conclusion: The HDR brachytherapy with 192Ir and 60Co sources on the up-to-date technology intensive devices provides a high accuracy of dose distributions when irradiating the malignant neoplasms with minimized radiationexposure to the «critical» tissues. Treatment results are improved therefore. The use of 192Ir radiation sources compared with 60Co ones resulted in an increased throughput of treatment, enhanced tumor regression, and reduced incidence of radiation effects on the critical organs. Currently we perform the radiobiological studies on somatic cellsfrom cancer patients at the genetic, biochemical, biophysical, and cytological levels in order to receive a biologicalindication of radiation damage under the impact of 192Ir isotope. Continuation of clinical trials with radiobiologicalsupport will provide an opportunity to predict the early and late radiation complications and thus to provide a personalized approach in brachytherapy of cancer patients using the 192Ir sources of γ-rays., (V. S. Ivankova, E. A. Domina, T. V. Khrulenko, L. M. Baranovska, O. O. Hrinchenko.)

Despite the consensus around the clinical potential of the α-emitting radionuclide astatine-211 ( 211 At), there are only a limited number of research facilities that work with this nuclide. There are three main reasons for this: (1) Scarce availability of the nuclide. Despite a relatively large number of globally existing cyclotrons capable of producing 211 At, few cyclotron facilities produce the nuclide on a regular basis. (2) Lack of a chemical infrastructure, that is, isolation of 211 At from irradiated targets and the subsequent synthesis of an astatinated product. At present, the research groups that work with 211 At depend on custom systems for recovering 211 At from the irradiated targets. Setting up and implementing such custom units require long lead times to provide a proper working system. (3) The chemistry of 211 At. Compared with radiometals there are no well-established and generally accepted synthesis methods for forming sufficiently stable bonds between 211 At and the tumor-specific vector to allow for systemic applications. Herein we present an overview of the infrastructure of producing 211 At radiopharmaceuticals, from target to radiolabeled product including chemical strategies to overcome hurdles for advancement into clinical trials with 211 At.

Among the available imaging techniques, functional imaging provided by nuclear medicine departments represents a tool of choice for the oncoradiotherapist for targeting tumour activity, with positron emission tomography as the main modality. Before, during or after radiotherapy, functional imaging helps guide the oncoradiotherapist in making decisions and in the strategic choice of pathology management. Setting up a working group to ensure perfect coordination at all levels is the first step. Key points for a common and coordinated management between the two departments are the definition of an organizational logistic, training of personnel at every levels, standardization of nomenclatures, the choice of adapted and common equipment, implementation of regulatory controls, and research/clinical routine continuum. The availability of functional examinations dedicated to radiotherapy in clinical routine is possible and requires a convergence of teams and a pooling of tools and techniques., (Copyright © 2020 Société française de radiothérapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.)

Electronic displays are used in every modern day medical clinic. They are used to view images that are needed to diagnose, treat, and follow-up on patients with a variety of conditions. The type of electronic display used varies from department to department. Currently, a type of displays called medical grade displays are used to evaluate and diagnose disease and conditions. Alternatively, commercial or entry level professional displays are used for almost everything else. In the field of radiation oncology medical images are often used to plan the treatment course for each patient. These images are always viewed using a commercial grade display. An experiment was completed to examine the role a medical grade display might have in a radiation oncology setting. Our study had certified dosimetrists and radiation oncologists view medical images on both a medical grade and commercial grade display and rank their preference on a scale. The observers assessed the images in different categories (Contrast, resolution, and sharpness) and also commented on their preference. Results indicated that the medical grade display performed better than the commercial grade display in every image quality category., (Copyright © 2019 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.)

Background: The IAEA recommends a quality assurance program in radiotherapy to ensure safe and effective treatments. In this study, radiotherapy departments were surveyed on their current practice including the extent and depth of quality assurance activities. Methods: Radiotherapy departments were voluntarily surveyed in three stages, firstly, in basic facility information, secondly, in quality assurance activities and treatment techniques, and thirdly, in a snapshot of quality assurance, departmental and treatment activities. Results: The IAEA received completed surveys from 381 radiotherapy departments throughout the world with 100 radiotherapy departments completing all three surveys. Dominant patterns were found in linac-based radiotherapy with access to treatment planning systems for 3D-CRT and 3D imaging. Staffing levels for major staff groups were on average in the range recommended by the IAEA. The modal patient workload per EBRT unit was as expected in the range of 21-30 patients per day, however significant instances of high workload (more than 50 patients per day per treatment unit) were reported. Staffing levels were found to correlate with amount of treatment equipment and patient workload. In a self-assessment of quality assurance performance, most radiotherapy departments reported that they would perform at least 60% of the quality assurance activities itemized in the second survey, with particular strength in equipment quality control. In a snapshot survey of quality assurance performance, again equipment quality control practice was well developed, particularly for the treatment equipment. Conclusions: The IAEA surveys provide a snapshot of current radiotherapy practice including quality assurance activities.

Historically, the gold standard for evaluation of cancer therapeutics, including medical devices, has been the randomized clinical trial. Although high-quality clinical data are essential for safe and judicious use of therapeutic oncology devices, class II devices require only preclinical data for US Food and Drug Administration approval and are often not rigorously evaluated prior to widespread uptake. Herein, we review master protocol design in medical oncology and its application to therapeutic oncology devices, using examples from radiation oncology. Unique challenges of clinical testing of radiation oncology devices (RODs) include patient and treatment heterogeneity, lack of funding for trials by industry and health-care payers, and operator dependence. To address these challenges, we propose the use of master protocols to optimize regulatory, financial, administrative, quality assurance, and statistical efficiency of trials evaluating RODs. These device-specific master protocols can be extrapolated to other devices and encompass multiple substudies with the same design, statistical considerations, logistics, and infrastructure. As a practical example, we outline our phase I and II master protocol trial of stereotactic magnetic resonance imaging-guided adaptive radiotherapy, which to the best of our knowledge is the first master protocol trial to test a ROD. Development of more efficient clinical trials is needed to promote thorough evaluation of therapeutic oncology devices, including RODs, in a resource-limited environment, allowing more practical and rapid identification of the most valuable advances in our field., (© The Author(s) 2019. Published by Oxford University Press.)

Purpose: Medical devices in radiation therapy undergo a complex process of Food and Drug Administration (FDA) approval. Little is known about which processes within the radiation therapy medical device industry are most prone to events involving wrong dose, volume, or targeting in radiation therapy treatment., Methods and Materials: We carried out a retrospective analysis of the United States FDA Medical Device Recalls database for recalls of products classified as "Accelerator, Linear, Medical" from 2010 to 2016. Each recall event was classified using a modified Delphi method among 3 experts in safety according to product type, error category, and severity score. Error categories included inconvenience; suboptimal plan or treatment; incorrect dose, volume, or targeting; and nonradiation injury risk. Variables investigated were product type, recall year, FDA-determined cause, and quantity of units recalled. Univariate and multivariate logistic regression were used to identify factors prognostic of incorrect dose, volume, or targeting., Results: We identified a total of 250 recall events between 2010 and 2016, with 165 eligible for analysis. Linear accelerators (LINACs) (28%) and LINAC control software (19%) were the most frequently recalled products. The most common FDA-determined causes for recalls were software design (42%) and device design (26%). On univariate analysis (P < .05), LINAC control software (odds ratio [OR] 5.4) and oncology information system or treatment management system (OR 3.9) versus LINACs and software design (OR 3.4) versus device design were associated with wrong dose, volume, or targeting events. On multivariate analysis, only the association with LINAC control software (OR 3.7) persisted for wrong dose, volume, or targeting events., Conclusions: Review of these data shows that problems with LINAC control software were associated with incorrect dose delivery at a 4-fold higher rate than errors with LINACs. Manufacturers should focus on improvements in software design to minimize dose- and targeting-related errors to patients., (Copyright © 2019 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.)

We evaluated the evolving structure of radiation oncology in Japan in terms of equipment, personnel, patient load and geographic distribution to identify and overcome any existing limitations. From March 2012 to August 2015, the Japanese Society for Radiation Oncology conducted a questionnaire based on the Japanese national structure survey of radiation oncology in 2011. Data were analyzed based on the institutional stratification by the annual number of new patients treated with radiotherapy per institution. The estimated annual numbers of new and total (new plus repeat) patients treated with radiation were 211 000 and 250 000, respectively. Additionally, the estimated cancer incidence was 851 537 cases with approximately 24.8% of all newly diagnosed patients being treated with radiation. The types and numbers of treatment devices actually used included linear accelerator (LINAC; n = 836), telecobalt (n = 3), Gamma Knife (n = 46), 60Co remote afterloading system (RALS; n = 24), and 192Ir RALS (n = 125). The LINAC system used dual-energy functions in 619 units, 3D conformal radiotherapy functions in 719 and intensity-modulated radiotherapy (IMRT) functions in 412. There were 756 JRS or JASTRO-certified radiation oncologists, 1018.5 full-time equivalent (FTE) radiation oncologists, 2026.7 FTE radiotherapy technologists, 149.1 FTE medical physicists, 141.5 FTE radiotherapy quality managers and 716.3 FTE nurses. The frequency of IMRT use significantly increased during this time. To conclude, although there was a shortage of personnel in 2011, the Japanese structure of radiation oncology has clearly improved in terms of equipment and utility., (© The Author(s) 2019. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.)

Purpose: To identify and report radiation oncologist (RO) workforce demographics, clinical workload trends, and equipment inventory in Canada., Methods and Materials: The Canadian Association of Radiation Oncology (CARO) distributed an online survey to RO administrative leaders at 47 Canadian cancer centers providing radiation therapy services from June to December 2017. The survey queried RO staff demographics, clinical workload, and equipment inventory from 2014 to 2016., Results: The response rate was 98% and represented 46 of 47 centers for analysis. In 2016, 510 ROs were in practice, with 98 ROs (19.2%) having <1.0 full-time equivalent (FTE) clinical work activities because of administration, research, or part-time employment. Most ROs worked full-time (92.0%), were affiliated with a university (77.5%), and worked in communities with a population >200,000 (84.9%). Approximately half (52.3%) were ≥46 years old. The male-to female ratio was 1.5:1 or higher in all regions of Canada except for Quebec, where there was no gender gap. Part-time employment was more common among female ROs (P < .01). Although FTE staff levels rose steadily between 2014 (456.3) and 2016 (475.8), an increase in patient workload resulted in a rise in the average annual consults per FTE-RO (from 257 to 267). Over a 2-year period, there were 63.5 FTE-recruitments and 44.0 FTE-departures (18.3 FTE-retirements; 25.7 FTE-migration) for a net gain of 19.5 RO-FTEs. An 8.4% increase in FTE staffing to 516 RO-FTEs in 2019 is anticipated, with 22 ROs expected to retire by 2019. There were 251 megavoltage linear accelerators across Canada, with most (39.8%) located in Ontario. Approximately one-fifth (20.7%) of these were older than 10 years and operating beyond the equipment's recommended life span., Conclusions: The Canadian RO workforce demonstrated incremental growth, but rising annual caseloads suggest that radiation therapy demand outpaced RO supply gains. Government funding is required to replace aging equipment in Canada., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: Communication is crucial in any clinical environment for efficient delivery of care and ensuring patient safety. A 2016 National Database of Nursing Quality Indicators questionnaire indicated poor physician-nurse satisfaction with communication in our department. We addressed gaps in our communication procedures by implementing a communication policy with a secure mobile messaging platform, and we surveyed care team members to evaluate the effectiveness of the implementation., Methods: We designed a policy around best communication practices and implemented a secure mobile messaging platform, Cureatr, which enables closed-loop, two-way communication that is compliant with the Health Insurance Portability and Accountability Act. Pre- and postimplementation surveys evaluated self-reported impression of efficiency, timeliness, effectiveness, and overall quality of communication, which were scored on a 5-point Likert scale. The number of messages sent was evaluated as a measure of uptake in use, and patient navigation data were queried to measure changes in clinic workflow., Results: After implementation of Cureatr and a communication policy, survey responses demonstrated a clear improvement in staff satisfaction with the efficiency, timeliness, effectiveness, and overall quality of communication. The number of messages sent reflected a progressive increase in use of Cureatr; however, a consistent improvement in clinical workflow as measured by a decrease in patient in-room time was not appreciated., Conclusion: Implementing a secure messaging application with a communication policy improved cancer care team satisfaction with communication on all levels. Additional work is needed to evaluate the impact of secure messaging on clinical workflows, patient satisfaction, and staff well-being.

Spatially fractionated radiation therapy represents a significant departure from canonical thinking in radiation oncology despite having origins in the early 1900s. The original and most common implementation of spatially fractionated radiation therapy uses commercially available blocks or multileaf collimators to deliver a nonconfluent, sieve-like pattern of radiation to the target volume in a nonuniform dose distribution. Dosimetrically, this is parameterized by the ratio of the valley dose in cold spots to the peak dose in hot spots, or the valley-to-peak dose ratio. The radiobiologic mechanisms are postulated to involve radiation-induced bystander effects, microvascular alterations, and/or immunomodulation. Current indications include bulky or locally advanced disease that would not be amenable to conventional radiation or that has proved refractory to chemoradiation. Early-phase clinical trials have shown remarkable success, with some response rates >90% and minimal toxicity. This has promoted technological developments in 3-dimensional formats (LATTICE), micron-size beams (microbeam), and proton arrays. Nevertheless, more clinical and biological data are needed to specify ideal dosimetry parameters and to formulate robust clinical indications and guidelines for optimal standardized care., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The application of structural shielding design techniques and goals as outlined in the National Council on Radiation Protection and Measurements Report 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities (2005), continues to be the basis for treatment vault design in 2018 with some updated information. Treatment techniques have changed significantly with the dominant usage of intensity-modulated radiation therapy techniques today based on concurrent imaging. Some of the developments in linear accelerator technology over the past 15 y include flattening filter-free modes, which enable higher instantaneous dose rates; three-dimensional conformal radiation therapy resulting in potentially higher workloads since healthy tissue is spared; improved intensity-modulated radiation therapy treatment delivery systems with lower monitor units per centigray delivered than traditional step and shoot intensity-modulated radiation therapy; stereotactic body radiation therapy with higher treatment fractions and increased workloads; and increased use of stereotactic radiosurgery with conventional linear accelerators as well as robotic arm-mounted linear accelerators with higher treatment fractions. These new treatment units also incorporate multiple-energy x-ray beams (2 to 5 MV typical), which require a significant change in the specification of a workload to be used in each vault. As the equipment in radiation oncology departments has evolved to state-of-the-art modalities, the requirements for adequate radiation shielding for these modalities has become more rigorous. Architectural designs no longer depend on standard maze design rectangular rooms. Innovative layouts and utilization of multiple layers of shielding materials allow much greater flexibility in room designs. Maze-less rooms with direct-shielded doors are part of these challenging designs and are very common today. Use of multiple-density concrete blocks allows quicker construction of vaults and requires less space for the equivalent shielding provided. Combinations of high-density or normal-density concrete, steel, and lead are used in designs to make optimum use of available space and cost. Additional shielding needed at the edges of these single- or bi-parting sliding doors as well as baffle designs for heating, ventilation, and air conditioning systems and communication cable penetrations require detailed calculations. Examples of these designs will be given in this presentation. Consideration of the radiation levels around the planned vault must also include adjacent multistory buildings.

Access to radiation facilities in low- and middle-income countries (LMIC) is far from optimal. Latin America and Africa represent 55% of LMIC, and radiation therapy facilities are available in only 70% and 46% of the countries, respectively. Only 3 countries in both regions meet the International Atomic Energy Agency's recommendation of 250,000 population per megavoltage machine (MVM). In Africa, the mean population served by 1 MVM is 3.56 million, compared with 0.65 million in Latin America. The distribution of radiation facilities in both regions varies according to income group. In Latin America, lower-middle-income countries have a distribution of 1.64 million inhabitants per MVM, as opposed to 0.64 and 0.49 million inhabitants per MVM in upper-middle- and high-income countries, respectively. In Africa, a distribution of 39.8, 2.47, and 0.8 million people per MVM is present in low-, lower-middle-, and upper-middle-income countries, respectively. Significant correlations were clearly demonstrated between population per MVM and gross domestic product (GDP) per capita (r = -0.3, P = .014), percentage of current health expenditure from GDP (r = -0.4, P = .014), life expectancy (r = -0.5, P = .0007), and cancer mortality incidence ratio (r = 0.4, P = .003). Stepwise multivariate regression showed that life expectancy was the only statistically significant factor (P = .001). These findings may indicate the detrimental impact of low radiation therapy coverage on life expectancy and cancer mortality incidence ratio in LMIC. It is noteworthy that in Latin America, a significant negative correlation was noted between population per MVM and GDP per capita (r = -0.6, P = .0004), as opposed to Africa (r = -0.4, P = .075). This indicates that African countries face challenges other than income level in addressing radiation therapy needs. More international efforts are urgently required to address the crisis of unmet radiation therapy needs in LMIC., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Deep learning has started to revolutionize several different industries, and the applications of these methods in medicine are now becoming more commonplace. This study focuses on investigating the feasibility of tracking patients and clinical staff wearing Bluetooth Low Energy (BLE) tags in a radiation oncology clinic using artificial neural networks (ANNs) and convolutional neural networks (CNNs). The performance of these networks was compared to relative received signal strength indicator (RSSI) thresholding and triangulation. By utilizing temporal information, a combined CNN+ANN network was capable of correctly identifying the location of the BLE tag with an accuracy of 99.9%. It outperformed a CNN model (accuracy = 94%), a thresholding model employing majority voting (accuracy = 95%), and a triangulation classifier utilizing majority voting (accuracy = 95%). Future studies will seek to deploy this affordable real time location system in hospitals to improve clinical workflow, efficiency, and patient safety., Competing Interests: The authors have declared that no competing interests exist.

Introduction:: Several efforts are being implemented at the European level to measure provision of up-to-date radiation treatments across the continent., Methods:: A snapshot survey involving all radiation oncology centers within Lombardy, Italy, was performed in 2012 and repeated in 2014 and 2016, in cooperation with regional governmental officers. Centers were asked to provide detailed information concerning all individual patients being treated on the index day, and to report data on available local resources., Results:: We observed an increase in the number of centers and of megavoltage units (MVU) (from 76 to 87, i.e., 8.7 MVU per million inhabitants in 2016). Mean number of MVU per center was 2.5. Average age of MVU increased from 5.3 to 7.5 years and patients on the waiting list also increased. Conformal 3D radiotherapy (RT) treatments decreased from 56% to 42% and were progressively replaced by intensity-modulated RT treatments (from 39% to 49%). Waiting times were overall satisfactory. Radiation oncologists treated on average 152 and radiation therapists 100 RT courses per year. Average reimbursement per course was €4,879 (range €2,476-€8,014)., Conclusions:: The methodology of snapshot survey proved feasible and provided valuable information about radiation oncology provision and accessibility in Lombardy.

Objectives: Lean management (LM) principles were first developed by a Japanese manufacturing company to maximise value and minimise waste in the automotive industry. However, these principles can also be applied in the healthcare sector. This study aimed to illustrate the process of implementing LM principles in a radiation oncology department to streamline workflow and identify and reduce waste., Methods: This study took place in the Department of Radiation Oncology, Royal Hospital, Muscat, Oman, in December 2016. A value stream map (VSM) was created for the chain of processes followed in the department. A waste analysis was conducted to determine which processes did not add value for the patient or healthcare provider., Results: Based on the VSM analysis, only six out of 13 steps were found to be of value. Necessary and unnecessary non-value-adding activities were identified. Sources of waste included parking and registration. In addition, variabilities in workload were noted., Conclusion: Overall, LM principles improve workflow, reduce waste and enhance patient and staff satisfaction. In the current study, the application of LM principles helped to improve value in a radiation oncology department., Competing Interests: CONFLICT OF INTEREST The authors declare no conflicts of interest.

Purpose: As a core component of a new gynecologic cancer radiation program, we envisioned, structured, and implemented a novel Interventional Radiation Oncology (IRO) unit and magnetic resonance (MR)-brachytherapy environment in an existing MR simulator., Methods and Materials: We describe the external and internal processes required over a 6-8 month time frame to develop a clinical and research program for gynecologic brachytherapy and to successfully convert an MR simulator into an IRO unit., Results: Support of the institution and department resulted in conversion of an MR simulator to a procedural suite. Development of the MR gynecologic brachytherapy program required novel equipment, staffing, infrastructural development, and cooperative team development with anesthetists, nurses, therapists, physicists, and physicians to ensure a safe and functional environment. Creation of a separate IRO unit permitted a novel billing structure., Conclusions: The creation of an MR-brachytherapy environment in an MR simulator is feasible. Developing infrastructure includes several collaborative elements. Unique to the field of radiation oncology, formalizing the space as an Interventional Radiation Oncology unit permits a sustainable financial structure., (Copyright © 2018 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Planning for radiation oncology requires reliable estimates of both demand for radiotherapy and availability of technological resources. This study compares radiotherapy resources in the 17 regions of the decentralised Spanish National Health System (SNHS)., Materials and Methods: The Sociedad Española de Oncología Radioterápica (SEOR) performed a cross-sectional survey of all Spanish radiation oncology services (ROS) in 2015. We collected data on SNHS radiotherapy units, recording the year of installation, specific features of linear accelerators (LINACs) and other treatment units, and radiotherapeutic techniques implemented by region. Any machine over 10 years old or lacking a multileaf collimator or portal imaging system was considered obsolete. We performed a k-means clustering analysis using the Hartigan-Wong method to test associations between the gross domestic regional product (GDRP), the number of LINACs per million population and the percentage of LINACs over 10 years old., Results: The SNHS controls 72 (61%) of the 118 Spanish ROS and has 180 LINACs, or 72.5% of the total public and private resources. The mean rate of LINACs per million population is 3.9 for public ROS, and 42% (n = 75) of the public accelerators were obsolete in 2015: 61 due to age and 14 due to technological capability. There was considerable regional variation in terms of the number and technological capacity of radiotherapy units; correlation between GRDP and resource availability was moderate., Conclusion: Despite improvements, new investments are still needed to replace obsolete units and increase access to modern radiotherapy. Regular analysis of ROS in each Spanish region is the only strategy for monitoring progress in radiotherapy capacity.

Purpose: To review the dosimetric, mechanical, and programmatic deficiencies most frequently observed during on-site visits of radiation therapy facilities by the Imaging and Radiation Oncology Core Quality Assurance Center in Houston (IROC Houston)., Methods and Materials: The findings of IROC Houston between 2000 and 2014, including 409 institutions and 1020 linear accelerators (linacs), were compiled. On-site evaluations by IROC Houston include verification of absolute calibration (tolerance of ±3%), relative dosimetric review (tolerances of ±2% between treatment planning system [TPS] calculation and measurement), mechanical evaluation (including multileaf collimator and kilovoltage-megavoltage isocenter evaluation against Task Group [TG]-142 tolerances), and general programmatic review (including institutional quality assurance program vs TG-40 and TG-142)., Results: An average of 3.1 deficiencies was identified at each institution visited, a number that has decreased slightly with time. The most common errors are tabulated and include TG-40/TG-142 compliance (82% of institutions were deficient), small field size output factors (59% of institutions had errors ≥3%), and wedge factors (33% of institutions had errors ≥3%). Dosimetric errors of ≥10%, including in beam calibration, were seen at many institutions., Conclusions: There is substantial room for improvement of both dosimetric and programmatic issues in radiation therapy, which should be a high priority for the medical physics community. Particularly relevant was suboptimal beam modeling in the TPS and a corresponding failure to detect these errors by not including TPS data in the linac quality assurance process., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: This study reports on the implementation of an electronic consent-to-treatment system (e-Consent) in a busy radiation medicine program and compares it with the previous paper-based method of documenting patient consent., Methods: A password-protected, electronic, e-Consent application was designed in-house and installed on iPad devices to document patient consent for radiation therapy treatments. A feasibility study, followed by a program-wide deployment of e-Consent, was executed. The effectiveness and impact of e-Consent on workflow were determined by comparing the number of problems arising from the paper-based consenting method with those from the e-Consent process. Staff satisfaction and perceived impact of e-Consent on workflow were determined by a program-wide survey of e-Consent users., Results: The e-Consent completion rate was 94.2% (5,600 of 5,943 forms) 1 year after implementation, indicating successful uptake at the program level. Although the paper-based method of documenting patient consent was associated with an error rate of 7% (24 of 343 forms), e-Consent was associated with an error rate of 0.32% (18 of 5,600 forms) 1 year after deployment. Results of a 10-item e-Consent user survey indicated improvement in staff workflow and high overall satisfaction with e-Consent., Conclusion: e-Consent is more efficient than paper-based methods for documenting patient consent. Moreover, replacing paper-based consent methods with an electronic version facilitated an improved workflow and staff satisfaction. Efforts aimed at implementing e-Consent throughout the entire cancer program are currently underway.

Introduction: Modern external beam radiation therapy treatment delivery processes potentially increase the number of tasks to be performed by therapists and thus opportunities for errors, yet the need to treat a large number of patients daily requires a balanced allocation of time per treatment slot. The goal of this work was to streamline the underlying workflow in such time-interval constrained processes to enhance both execution efficiency and active safety surveillance using a Kaizen approach., Methods and Materials: A Kaizen project was initiated by mapping the workflow within each treatment slot for 3 Varian TrueBeam linear accelerators. More than 90 steps were identified, and average execution times for each were measured. The time-consuming steps were stratified into a 2 × 2 matrix arranged by potential workflow improvement versus the level of corrective effort required. A work plan was created to launch initiatives with high potential for workflow improvement but modest effort to implement. Time spent on safety surveillance and average durations of treatment slots were used to assess corresponding workflow improvements., Results: Three initiatives were implemented to mitigate unnecessary therapist motion, overprocessing of data, and wait time for data transfer defects, respectively. A fourth initiative was implemented to make the division of labor by treating therapists as well as peer review more explicit. The average duration of treatment slots reduced by 6.7% in the 9 months following implementation of the initiatives (P = .001). A reduction of 21% in duration of treatment slots was observed on 1 of the machines (P < .001). Time spent on safety reviews remained the same (20% of the allocated interval), but the peer review component increased., Conclusions: The Kaizen approach has the potential to improve operational efficiency and safety with quick turnaround in radiation therapy practice by addressing non-value-adding steps characteristic of individual department workflows. Higher effort opportunities are identified to guide continual downstream quality improvements., (Copyright © 2017 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.)

Background: With increasing recognition of growing cancer incidence globally, efficient means of expanding radiotherapy capacity is imperative, and understanding the factors impacting human and financial needs is valuable., Materials and Methods: A time-driven activity-based costing analysis was performed, using a base case of 2-machine departments, with defined cost inputs and operating parameters. Four income groups were analysed, ranging from low to high income. Scenario analyses included department size, operating hours, fractionation, treatment complexity, efficiency, and centralised versus decentralised care., Results: The base case cost/course is US$5,368 in HICs, US$2,028 in LICs; the annual operating cost is US$4,595,000 and US$1,736,000, respectively. Economies of scale show cost/course decreasing with increasing department size, mainly related to the equipment cost and most prominent up to 3 linacs. The cost in HICs is two or three times as high as in U-MICs or LICs, respectively. Decreasing operating hours below 8h/day has a dramatic impact on the cost/course. IMRT increases the cost/course by 22%. Centralising preparatory activities has a moderate impact on the costs., Conclusions: The results indicate trends that are useful for optimising local and regional circumstances. This methodology can provide input into a uniform and accepted approach to evaluating the cost of radiotherapy., (Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.)

Purpose: To analyze all recalls involving radiation oncology devices (RODs) from the US Food and Drug Administration (FDA)'s recall database, comparing these with non-radiation oncology device recalls to identify discipline-specific trends that may inform improvements in device safety., Methods and Materials: Recall data on RODs from 2002 to 2015 were sorted into 4 product categories (external beam, brachytherapy, planning systems, and simulation systems). Outcomes included determined cause of recall, recall class (severity), quantity in commerce, time until recall termination (date FDA determines recall is complete), and time since 510(k) approval. Descriptive statistics were performed with linear regression of time-series data. Results for RODs were compared with those for other devices by Pearson χ 2 test for categorical data and 2-sample Kolmogorov-Smirnov test for distributions., Results: There were 502 ROD recalls and 9534 other class II device recalls during 2002 to 2015. Most recalls were for external beam devices (66.7%) and planning systems (22.9%), and recall events peaked in 2011. Radiation oncology devices differed significantly from other devices in all recall outcomes (P≤.04). Recall cause was commonly software related (49% vs 10% for other devices). Recall severity was more often moderate among RODs (97.6% vs 87.2%) instead of severe (0.2% vs 4.4%; P<.001). Time from 510(k) market approval to recall was shorter among RODs (P<.001) and progressively shortened over time. Radiation oncology devices had fewer recalled devices in commerce than other devices (P<.001)., Conclusions: Compared with other class II devices, RODs experience recalls sooner after market approval and are trending sooner still. Most of these recalls were moderate in severity, and software issues are prevalent. Comprehensive analysis of recall data can identify areas for device improvement, such as better system design among RODs., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: To determine clinic-specific linear accelerator quality assurance (QA) TG-142 test frequencies, to maximize physicist time efficiency and patient treatment quality., Methods and Materials: A novel quantitative approach to failure mode and effect analysis is proposed. Nine linear accelerator-years of QA records provided data on failure occurrence rates. The severity of test failure was modeled by introducing corresponding errors into head and neck intensity modulated radiation therapy treatment plans. The relative risk of daily linear accelerator QA was calculated as a function of frequency of test performance., Results: Although the failure severity was greatest for daily imaging QA (imaging vs treatment isocenter and imaging positioning/repositioning), the failure occurrence rate was greatest for output and laser testing. The composite ranking results suggest that performing output and lasers tests daily, imaging versus treatment isocenter and imaging positioning/repositioning tests weekly, and optical distance indicator and jaws versus light field tests biweekly would be acceptable for non-stereotactic radiosurgery/stereotactic body radiation therapy linear accelerators., Conclusions: Failure mode and effect analysis is a useful tool to determine the relative importance of QA tests from TG-142. Because there are practical time limitations on how many QA tests can be performed, this analysis highlights which tests are the most important and suggests the frequency of testing based on each test's risk priority number., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The massive global shortfall in radiotherapy equipment and human resources in developing countries is an enormous challenge for international efforts in cancer control. This lack of access to treatment has been long-standing, but there is now a growing consensus about the urgent need to prioritize solutions to this problem and that a global strategy is required for them to be successful. An essential element of making radiotherapy universally accessible is a coordinated approach to clinical training and practice. This has been recently recognized by many university departments and clinical training programs. However, formalized training and career promotion tracks in global health within radiation oncology have been slow to emerge, thereby limiting the sustained involvement of students and faculty, and restricting opportunities for leadership in this space. We examine here potential structures and benefits of formalized global health training in radiation oncology. We explore how defining specific competencies in this area can help trainees and practitioners integrate their activities in global health within their existing roles as clinicians, educators, or scientists. This would also help create a new global health track for academic advancement, which could focus on such domains as implementation science, health service, and advocacy. We discuss how effective mentorship models, international partnerships, and institutional twinning arrangements support this work and explore how new resources and funding models might be used to further develop and expand radiation oncology services globally., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Medical linear accelerators (linacs) and cobalt-60 machines are both mature technologies for external beam radiotherapy. A comparison is made between these two technologies in terms of infrastructure and maintenance, dosimetry, shielding requirements, staffing, costs, security, patient throughput and clinical use. Infrastructure and maintenance are more demanding for linacs due to the complex electric componentry. In dosimetry, a higher beam energy, modulated dose rate and smaller focal spot size mean that it is easier to create an optimised treatment with a linac for conformal dose coverage of the tumour while sparing healthy organs at risk. In shielding, the requirements for a concrete bunker are similar for cobalt-60 machines and linacs but extra shielding and protection from neutrons are required for linacs. Staffing levels can be higher for linacs and more staff training is required for linacs. Life cycle costs are higher for linacs, especially multi-energy linacs. Security is more complex for cobalt-60 machines because of the high activity radioactive source. Patient throughput can be affected by source decay for cobalt-60 machines but poor maintenance and breakdowns can severely affect patient throughput for linacs. In clinical use, more complex treatment techniques are easier to achieve with linacs, and the availability of electron beams on high-energy linacs can be useful for certain treatments. In summary, there is no simple answer to the question of the choice of either cobalt-60 machines or linacs for radiotherapy in low- and middle-income countries. In fact a radiotherapy department with a combination of technologies, including orthovoltage X-ray units, may be an option. Local needs, conditions and resources will have to be factored into any decision on technology taking into account the characteristics of both forms of teletherapy, with the primary goal being the sustainability of the radiotherapy service over the useful lifetime of the equipment., (Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Purpose: Radiation oncology relies on rapidly evolving technology and highly complex processes. The US Food and Drug Administration collects reports of adverse events related to medical devices. We sought to characterize all events involving radiation oncology devices (RODs) from the US Food and Drug Administration's postmarket surveillance Manufacturer and User Facility Device Experience (MAUDE) database, comparing these with non-radiation oncology devices., Methods and Materials: MAUDE data on RODs from 1991 to 2015 were sorted into 4 product categories (external beam, brachytherapy, planning systems, and simulation systems) and 5 device problem categories (software, mechanical, electrical, user error, and dose delivery impact). Outcomes included whether the device was evaluated by the manufacturer, adverse event type, remedial action, problem code, device age, and time since 510(k) approval. Descriptive statistics were performed with linear regression of time-series data. Results for RODs were compared with those for other devices by the Pearson χ 2 test for categorical data and 2-sample Kolmogorov-Smirnov test for distributions., Results: There were 4234 ROD and 4,985,698 other device adverse event reports. Adverse event reports increased over time, and events involving RODs peaked in 2011. Most ROD reports involved external beam therapy (50.8%), followed by brachytherapy (24.9%) and treatment planning systems (21.6%). The top problem types were software (30.4%), mechanical (20.9%), and user error (20.4%). RODs differed significantly from other devices in each outcome (P<.001). RODs were more likely to be evaluated by the manufacturer after an event (46.9% vs 33.0%) but less likely to be recalled (10.5% vs 37.9%) (P<.001). Device age and time since 510(k) approval were shorter among RODs (P<.001)., Conclusions: Compared with other devices, RODs may experience adverse events sooner after manufacture and market approval. Close postmarket surveillance, improved software design, and manufacturer-user training may help mitigate these events., Competing Interests: Drs Hattangadi-Gluth, Cervino, and Moore hold research funding from Varian Medical Systems, unrelated to the current study., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: Radiation treatment planning involves a complex workflow that has multiple potential points of vulnerability. This study utilizes an incident reporting system to identify the origination and detection points of near-miss errors, in order to guide their departmental safety improvement efforts. Previous studies have examined where errors arise, but not where they are detected or applied a near-miss risk index (NMRI) to gauge severity., Methods: From 3/2012 to 3/2014, 1897 incidents were analyzed from a departmental incident learning system. All incidents were prospectively reviewed weekly by a multidisciplinary team and assigned a NMRI score ranging from 0 to 4 reflecting potential harm to the patient (no potential harm to potential critical harm). Incidents were classified by point of incident origination and detection based on a 103-step workflow. The individual steps were divided among nine broad workflow categories (patient assessment, imaging for radiation therapy (RT) planning, treatment planning, pretreatment plan review, treatment delivery, on-treatment quality management, post-treatment completion, equipment/software quality management, and other). The average NMRI scores of incidents originating or detected within each broad workflow area were calculated. Additionally, out of 103 individual process steps, 35 were classified as safety barriers, the process steps whose primary function is to catch errors. The safety barriers which most frequently detected incidents were identified and analyzed. Finally, the distance between event origination and detection was explored by grouping events by the number of broad workflow area events passed through before detection, and average NMRI scores were compared., Results: Near-miss incidents most commonly originated within treatment planning (33%). However, the incidents with the highest average NMRI scores originated during imaging for RT planning (NMRI = 2.0, average NMRI of all events = 1.5), specifically during the documentation of patient positioning and localization of the patient. Incidents were most frequently detected during treatment delivery (30%), and incidents identified at this point also had higher severity scores than other workflow areas (NMRI = 1.6). Incidents identified during on-treatment quality management were also more severe (NMRI = 1.7), and the specific process steps of reviewing portal and CBCT images tended to catch highest-severity incidents. On average, safety barriers caught 46% of all incidents, most frequently at physics chart review, therapist's chart check, and the review of portal images; however, most of the incidents that pass through a particular safety barrier are not designed to be capable of being captured at that barrier., Conclusions: Incident learning systems can be used to assess the most common points of error origination and detection in radiation oncology. This can help tailor safety improvement efforts and target the highest impact portions of the workflow. The most severe near-miss events tend to originate during simulation, with the most severe near-miss events detected at the time of patient treatment. Safety barriers can be improved to allow earlier detection of near-miss events.

Background: Unscheduled accelerator downtime can negatively impact the quality of life of patients during their struggle against cancer. Currently digital data accumulated in the accelerator system is not being exploited in a systematic manner to assist in more efficient deployment of service engineering resources. The purpose of this study is to develop an effective process for detecting unexpected deviations in accelerator system operating parameters and/or performance that predicts component failure or system dysfunction and allows maintenance to be performed prior to the actuation of interlocks., Methods: The proposed predictive maintenance (PdM) model is as follows: 1) deliver a daily quality assurance (QA) treatment; 2) automatically transfer and interrogate the resulting log files; 3) once baselines are established, subject daily operating and performance values to statistical process control (SPC) analysis; 4) determine if any alarms have been triggered; and 5) alert facility and system service engineers. A robust volumetric modulated arc QA treatment is delivered to establish mean operating values and perform continuous sampling and monitoring using SPC methodology. Chart limits are calculated using a hybrid technique that includes the use of the standard SPC 3σ limits and an empirical factor based on the parameter/system specification., Results: There are 7 accelerators currently under active surveillance. Currently 45 parameters plus each MLC leaf (120) are analyzed using Individual and Moving Range (I/MR) charts. The initial warning and alarm rule is as follows: warning (2 out of 3 consecutive values ≥ 2σ hybrid) and alarm (2 out of 3 consecutive values or 3 out of 5 consecutive values ≥ 3σ hybrid). A customized graphical user interface provides a means to review the SPC charts for each parameter and a visual color code to alert the reviewer of parameter status. Forty-five synthetic errors/changes were introduced to test the effectiveness of our initial chart limits. Forty-three of the forty-five errors (95.6 %) were detected in either the I or MR chart for each of the subsystems monitored., Conclusion: Our PdM model shows promise in providing a means for reducing unscheduled downtime. Long term monitoring will be required to establish the effectiveness of the model.

The field of veterinary radiation therapy (RT) has gained substantial momentum in recent decades with significant advances in conformal treatment planning, image-guided radiation therapy (IGRT), and intensity-modulated (IMRT) techniques. At the root of these advancements lie improvements in tumor imaging, image alignment (registration), target volume delineation, and identification of critical structures. Image registration has been widely used to combine information from multimodality images such as computerized tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) to improve the accuracy of radiation delivery and reliably identify tumor-bearing areas. Many different techniques have been applied in image registration. This review provides an overview of medical image registration in RT and its applications in veterinary oncology. A summary of the most commonly used approaches in human and veterinary medicine is presented along with their current use in IGRT and adaptive radiation therapy (ART). It is important to realize that registration does not guarantee that target volumes, such as the gross tumor volume (GTV), are correctly identified on the image being registered, as limitations unique to registration algorithms exist. Research involving novel registration frameworks for automatic segmentation of tumor volumes is ongoing and comparative oncology programs offer a unique opportunity to test the efficacy of proposed algorithms., (© 2016 American College of Veterinary Radiology.)

Ionizing radiations interact with molecules at the cellular and molecular levels leading to several biochemical modifications that may be responsible for biological effects on tissue or whole organisms. The study of these changes is difficult because of the complexity of the biological response(s) to radiations and the lack of reliable models able to mimic the whole molecular phenomenon and different communications between the various cell networks, from the cell activation to the macroscopic effect at the tissue or organismal level. Microfluidics, the science and technology of systems that can handle small amounts of fluids in confined and controlled environment, has been an emerging field for several years. Some microfluidic devices, even at early stages of development, may already help radiobiological research by proposing new approaches to study cellular, tissue and total-body behavior upon irradiation. These devices may also be used in clinical biodosimetry since microfluidic technology is frequently developed for integrating complex bioassay chemistries into automated user-friendly, reproducible and sensitive analyses. In this review, we discuss the use, numerous advantages, and possible future of microfluidic technology in the field of radiobiology. We will also examine the disadvantages and required improvements for microfluidics to be fully practical in radiation research and to become an enabling tool for radiobiologists and radiation oncologists., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

One of the major issues potentially limiting treatment planning with solely MR images is the possibility of geometric distortion inherent in MR images. We designed a large distortion phantom containing a 3D array of spheres and proposed a three-dimensional (3D) approach to determine the distortion of MR image volume. The approach to overcome partially filled spheres is also presented. The phantom was assembled with a 3D array of spheres filled with contrast and was scanned with a 3T MRI simulator. A 3D whole-sphere or half-sphere template is used to match the image pattern. The half-sphere template is used when the normalized cross-correlation value for the whole-sphere template is below a predetermined threshold. Procrustes method was applied to remove the shift induced by rotation and translation of the phantom. Then the distortion map was generated. Accuracy of the method was verified using CT images of a small phantom of the same design. The analysis of the small phantom showed that the method is accurate with an average offset of estimated sphere center 0.12 ± 0.04 mm. The Procrustes analysis estimated the rotation angle to be 1.95° and 0.01°, respectively, when the phantom was placed at 2° and 0° from the ceiling laser. The analysis showed that on the central plane through the magnet center, the average displacement is less than 1 mm for all radii. At distal planes, when the radius is less than 18 cm, the average displacement is less than 1 mm. However, the average displacement is over 1 mm but still less than 1.5 mm for larger radii. A large distortion phantom was assembled and analysis software was developed to characterize distortions in MRI scans. The use of two templates helps reduce the potential impact of residual air bubbles in some of the spheres.