PURPOSE To provide recommendations on training guidelines for therapeutic medical physics residents, including standards for satisfaction of the Nuclear Regulatory Commission (NRC) Authorized Medical Physicist (AMP) high-dose-rate (HDR) brachytherapy training and experience requirements. METHODS AND MATERIALS Following the Nominal Group Technique, an expert panel of 15 American Board of Radiology-certified medical physicists from 14 institutions, including academic centers and freestanding clinics, developed consensus recommendations that align with NRC form 313A (AMP). RESULTS Training and experience requirements were defined at two levels. Level I addresses NRC training requirements and focuses on foundational HDR brachytherapy competencies. Trainees should understand quality assurance (QA) equipment needs, perform or describe all QA procedures, and demonstrate knowledge of shielding principles, regulatory dose limits, and emergency procedures. Clinical training should include at least 10 3D planned cases, 6 involving 2 or more channels. Level II addresses NRC work experience requirements. Trainees must meet all Level I standards and be capable of performing Level I clinical duties, providing QA and clinical guidance for new applicators or techniques, as well as emergency training for staff. Level II experience requires a minimum of 15 3D planned cases, including at least seven interstitial procedures (hybrid applicators allowed) and no more than five single-channel cases. CONCLUSIONS Proper training and experience are essential for HDR brachytherapy. The two levels defined in this work offer a clear, structured pathway for trainees to achieve AMP status and ensure readiness for independent practice.

BACKGROUND:Following the release in 2016 of the report of the American Association of Physicists in Medicine Task Group 100, there has been growing interest in the use of prospective hazard analysis in radiation therapy. System Theoretic Process Analysis (STPA) is an emerging technique in this domain that is particularly suited to processes that involve time sensitive collaboration, decision-making and/or automation. PURPOSE:The goal of this research was to use STPA to evaluate existing processes and procedures with an aim to identify improvements, gaps or unforeseen risks stemming from implementing real-time adaptive treatment on a helical tomotherapy platform. METHODS:The Radixact treatment delivery system (Accuray Inc., Sunnyvale, CA, USA), an evolution of the Tomotherapy platform, incorporates upgrades such as the Synchrony system for real-time motion monitoring and treatment adaptation. In collaboration with a team from the radiation oncology department of a large public hospital, a prospective hazard analysis focused on the real-time adaptive capabilities of the Radixact Synchrony system was conducted using STPA. The system boundaries were defined and a control structure model comprising sub-systems and control actions was developed. Unsafe control actions were identified and broad-based causal scenarios were generated. The causal scenarios that were novel, specific to Synchrony or challenging to mitigate were selected for further analysis regarding impacts and potential causes, following which mitigation strategies were proposed, taking into consideration the hierarchy of controls. RESULTS:A control structure model encompassing the entire patient journey was developed, incorporating all the hardware and software components and human decision makers. The model consisted of 12 sub-systems and 21 control actions, resulting in 108 unsafe control actions and 595 causal scenarios. Sixty-one causal scenarios were selected for further analysis, for which mitigation strategies were proposed based on the hierarchy of controls. These included the development of better reference documentation, the systematic testing of the sensitivity of tracking performance to changes in tracking parameters, guidance around setting and documenting tracking parameters, and documentation review. CONCLUSIONS:STPA was effectively used to assess the Radixact Synchrony system's real-time adaptive radiation therapy capabilities, providing insight into how the system could become unsafe throughout the patient journey. While focused on Radixact Synchrony and real-time adaptive radiation therapy, this study offers a transferable example of STPA application, from analysis initialization to mitigation, that can inform other safety assessments in radiation therapy.

This study assesses the ability of a helical tomotherapy system equipped with kV imaging and optical surface guidance to adapt to motion traces in real-time. To assess the delivery accuracy with motion, a unified testing framework was used. The average 2 %/2 mm γ-fail rates across all lung traces were 0.1 % for motion adapted and 17.4 % for no motion correction. Average 2 %/2 mm γ-fail rates across all prostate traces were 0.4 % for motion adapted and 12.2 % for no motion correction. Real-time motion adaption was shown to improve the accuracy of dose delivered to a moving phantom compared with no motion adaption. MeSH Keywords: Radiotherapy, image-guided; Radiation therapy, targeted.

The purpose of this document is to provide the qualified medical physicist (QMP) with guidance on the critical evaluation and independent validation of “closed” or “black box” systems in a radiation oncology setting. Radiotherapy delivery systems and their associated subsystems are highly sophisticated and complicated. In recent years, vendors have worked closely with QMPs, information technology (IT) personnel, and clinical engineers to develop and ultimately provide an entire package of resources at the time of purchase of radiotherapy delivery equipment. Commissioning and routine quality assurance (QA) on these new, black‐box systems is not necessarily more difficult or time‐consuming; however, there are different factors to consider with black‐boxes. Independence in the vendor's own validation techniques now becomes critical to establish. For vendor‐provided tools, the user must understand the implications of working with a service tool or a true QA tool. Lastly, the user must determine which components of the system are unknown and differ from a classic white‐box system. Understanding these characteristics of the black‐box will guide the user in determining which quality management (QM) tools are applicable and which verification and validation (V&V) procedures to follow. Black‐box systems are becoming more and more prevalent in the radiation oncology setting. For example, true black‐box systems in the form of machine learning (ML) algorithms are already widely used within common treatment planning systems (TPS). These systems present a unique challenge to the QMP who is responsible for conducting independent V&V performance measurements on such systems. Although these systems require a different approach from classic treatment delivery systems, we present new terms for characterizing black‐box systems and a methodology for using alternative methods of independent validation.

The purpose of this document is to provide the qualified medical physicist (QMP) with guidance on the critical evaluation and independent validation of “closed” or “black box” systems in a radiation oncology setting. Radiotherapy delivery systems and their associated subsystems are highly sophisticated and complicated. In recent years, vendors have worked closely with QMPs, information technology (IT) personnel, and clinical engineers to develop and ultimately provide an entire package of resources at the time of purchase of radiotherapy delivery equipment. Commissioning and routine quality assurance (QA) on these new, black-box systems is not necessarily more difficult or time-consuming; however, there are different factors to consider with black-boxes. Independence in the vendor's own validation techniques now becomes critical to establish. For vendor-provided tools, the user must understand the implications of working with a service tool or a true QA tool. Lastly, the user must determine which components of the system are unknown and differ from a classic white-box system. Understanding these characteristics of the black-box will guide the user in determining which quality management (QM) tools are applicable and which verification and validation (V&V) procedures to follow. Black-box systems are becoming more and more prevalent in the radiation oncology setting. For example, true black-box systems in the form of machine learning (ML) algorithms are already widely used within common treatment planning systems (TPS). These systems present a unique challenge to the QMP who is responsible for conducting independent V&V performance measurements on such systems. Although these systems require a different approach from classic treatment delivery systems, we present new terms for characterizing black-box systems and a methodology for using alternative methods of independent validation.

INTRODUCTION:Prospective hazard analysis (PHA) was introduced to the wider medical physics community by the initiation of American association of physicists in medicine task group 100 in 2003. Since then, there has been increasing interest in the applicability of PHA to radiotherapy for the purpose of keeping patients safe and assessing the risks within the whole practice of radiotherapy. The purpose of this research was to review the PHA literature focusing on which techniques and technologies have been assessed, how they have been assessed, and what can be learnt. METHODS:The search for English language, peer-reviewed, full-text articles was conducted across five databases and the citations of three seminal papers using a common search strategy. The collation, filtration, and analysis of articles was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement reporting standard utilizing the following PICOS approach: Population: x-ray external beam radiation therapy, Intervention: prospective hazard analysis, Comparison: none, Outcome: patient safety, Study characteristics: details of applied technique. RESULTS:689 unique studies were identified. 62 were determined to be eligible for inclusion. PHA has been applied to C-arm treatment systems (17), stereotactic radiosurgery (8), TomoTherapy (6), stereotactic body radiotherapy (5), Ethos (5), Halcyon (3), MRIdian (3), review activities (3), commissioning (2), unity (1), volumetric modulated arc therapy (1), surface guidance (1), CyberKnife (1), RefleXion (1) and other novel software and hardware systems (6). Disciplines involved in the studies were physicists (92%), physicians (75%), radiation therapists or dosimetrists (71%), external experts (38%), and facilitators (33%). Failure mode and effects analysis (FMEA) was used in 75% of studies, 10% used FMEA derived methods, 10% used system theoretic process analysis, and 5% used other methods. From the FMEA studies, 579 high-risk failure modes were extracted covering all aspects of the radiotherapy process, 50% applied to patient treatment delivery sessions and 25% applied to contouring and treatment planning. The mitigation strategies recommended by studies tended to add to the departmental workload. CONCLUSIONS:62 studies were identified that used PHA in radiotherapy, within the included studies: patient journey was the most analyzed process, of the disciplines physicists were involved in the most studies, FMEA the most common technique, and the delivery of patient treatment was the greatest source of high-risk failure modes.

Prospective hazard analysis (PHA) was introduced to the wider medical physics community by the initiation of American association of physicists in medicine task group 100 in 2003. Since then, there has been increasing interest in the applicability of PHA to radiotherapy for the purpose of keeping patients safe and assessing the risks within the whole practice of radiotherapy. The purpose of this research was to review the PHA literature focusing on which techniques and technologies have been assessed, how they have been assessed, and what can be learnt. The search for English language, peer-reviewed, full-text articles was conducted across five databases and the citations of three seminal papers using a common search strategy. The collation, filtration, and analysis of articles was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement reporting standard utilizing the following PICOS approach: Population: x-ray external beam radiation therapy, Intervention: prospective hazard analysis, Comparison: none, Outcome: patient safety, Study characteristics: details of applied technique. 689 unique studies were identified. 62 were determined to be eligible for inclusion. PHA has been applied to C-arm treatment systems (17), stereotactic radiosurgery (8), TomoTherapy (6), stereotactic body radiotherapy (5), Ethos (5), Halcyon (3), MRIdian (3), review activities (3), commissioning (2), unity (1), volumetric modulated arc therapy (1), surface guidance (1), CyberKnife (1), RefleXion (1) and other novel software and hardware systems (6). Disciplines involved in the studies were physicists (92%), physicians (75%), radiation therapists or dosimetrists (71%), external experts (38%), and facilitators (33%). Failure mode and effects analysis (FMEA) was used in 75% of studies, 10% used FMEA derived methods, 10% used system theoretic process analysis, and 5% used other methods. From the FMEA studies, 579 high-risk failure modes were extracted covering all aspects of the radiotherapy process, 50% applied to patient treatment delivery sessions and 25% applied to contouring and treatment planning. The mitigation strategies recommended by studies tended to add to the departmental workload. 62 studies were identified that used PHA in radiotherapy, within the included studies: patient journey was the most analyzed process, of the disciplines physicists were involved in the most studies, FMEA the most common technique, and the delivery of patient treatment was the greatest source of high-risk failure modes.

AAPM Task Group Report 135.B covers new technology components that have been added to an established radiosurgery platform and updates the components that were not well covered in the previous report. Considering the current state of the platform, this task group (TG) is a combination of a foundational task group to establish the basis for new processes/technology and an educational task group updating guidelines on the established components of the platform. Because the technology discussed in this document has a relatively small user base compared to C-arm isocentric linacs, the authors chose to emphasize the educational components to assist medical physicists who are new to the technology and have not had the opportunity to receive in-depth vendor training at the time of reading this report. The TG has developed codes of practice, introduced QA, and developed guidelines which are generally expected to become enduring practice. This report makes prescriptive recommendations as there has not been enough longitudinal experience with some of the new technical components to develop a data-based risk analysis.

Purpose/Objective(s) Accurate needle localization technique is vital for a successful prostate HDR implant as it directly affects the plan quality and accurate dose delivery. Modern transrectal ultrasound and stepper systems provide two distinct volume acquisition modes: stepping transverse (ST) mode and twister sagittal mode (TS). The aim of this study is to quantify and compare the intra- and inter-observer variability (Intra-OV and Inter-OV) of catheter localization accuracy with both acquisition modes. Materials/Methods A total of 329 paired points of catheter tip from both ST and TS modes were defined by 7 observers (2 Physicians, 5 Physicists) from retrospective clinical plans. Each mode of images was presented, and the observers were asked to define the tip of catheters using 3D slice viewing software. Their coordinates were recorded along the Left-Right (LR), Anterior-Posterior (AP), and Superior-Inferior (SI, or depth) directions. For Intra-OV, the difference between the catheter tip positions to the reference position inferred by the physically measured free length positions were compared between the ST and TS modes for each observer. For Inter-OV quantification, the statistical variance in tip positions along all three cartesian directions defined by 7 observers were computed, and the values between the ST and TS modes were compared using a one-sided paired t-Test. Results Statistically significant differences in Inter-OV were observed in SI and LR directions only. For defining the depth of the needle, the sagittal mode reduced variability by 29.0% compared to the transverse mode (0.56mm vs 0.75mm, p < 0.05). For delineation of the left-right positioning of the needle, the transverse mode was more consistent than the sagittal mode, with a 22.2% reduction in mean Inter-OV (0.36mm vs 0.45mm, p < 0.05). For Intra-OV, the mean differences between the user defined tip points to the physical free length measurements were smaller for the sagittal mode than the transverse mode (0.03mm vs 0.69mm for TS and ST, respectively). Conclusion The different volume acquisition modes in transrectal ultrasound produce statistically significant differences in how the catheter is reconstructed during prostate HDR brachytherapy procedures. Each mode showed superiority in reducing observer variation along the different directions, with ST mode improving LR delineation and TS mode improving depth delineation. Both modes of image acquisition are complimentary for more accurate and precise catheter reconstruction for prostate HDR brachytherapy planning. Further investigation in how these variances affect dose distribution will be important to improving patient outcomes.

Abstract Purpose The purpose of this work is to evaluate the Hyperscint‐RP100 scintillation dosimetry research platform (Hyperscint‐RP100, Medscint Inc., Quebec, QC, Canada) designed for clinical quality assurance (QA) for use in in vivo dosimetry measurements. Methods The pre‐clinical evaluation of the scintillator was performed using a Varian TrueBeam linear accelerator. Dependency on field size, depth, dose, dose rate, and temperature were evaluated in a water tank and compared to calibration data from commissioning and annual QA. Angularity was evaluated with a 3D printed phantom. The clinical evaluation was first performed in two cadaver dogs, and then in three companion animal dogs receiving radiation therapy for nasal tumors. A treatment planning CT scan was performed for cadavers and clinical patients. Prior to treatment, the probe was inserted into the radiation field. Radiation was then delivered and measured with the scintillator. For cadavers, the treatment was repeated after making an intentional shift in patient position to simulate a treatment error. Results In the preclinical measurements the dose differed from annual measurements as follows: field size −0.77 to 0.43%, depth dose −0.36 to 1.14%, dose −0.54 to 2.93%, dose rate 0.3 to 3.6%, and angularity −1.18 to 0.01%. Temperature dependency required a correction factor of 0.11%/°C. In the two cadavers, the dose differed by −1.17 to 0.91%. The device correctly detected the treatment error when the heads were intentionally laterally shifted. In three canine clinical patients treated in multiple fractions, the detected dose ranged from 98.33 to 103.15%. Conclusion Results of this new device are promising although more work is necessary to fully validate it for clinical dosimetry.

While most Radiation Oncology clinics have adopted electronic charting in one form or another, no consensus document exists that provides guidelines for safe and effective use of the Radiation Oncology electronic medical records (RO-EMR). Task Group 262 was formed to provide these guidelines as well as to provide recommendations to vendors for improving electronic charting functionality in future. Guidelines are provided in the following areas: Implementation and training for the RO-EMR, acceptance testing and quality assurance (QA) of the RO-EMR, use of the RO-EMR as an information repository, use of the RO-EMR as a workflow manager, electronic charting for brachytherapy and nonstandard treatments, and information technology (IT) considerations associated with the RO-EMR. The report was based on a literature search by the task group, an extensive survey of task group members on their respective RO-EMR practices, an AAPM membership survey on electronic charting, as well as group consensus.

The era of real-time radiotherapy is upon us. Robotic and gimbaled linac tracking are clinically established technologies with the clinical realization of couch tracking in development. Multileaf collimators (MLCs) are a standard equipment for most cancer radiotherapy systems, and therefore MLC tracking is a potentially widely available technology. MLC tracking has been the subject of theoretical and experimental research for decades and was first implemented for patient treatments in 2013. The AAPM Task Group 264 Safe Clinical Implementation of MLC Tracking in Radiotherapy Report was charged to proactively provide the broader radiation oncology community with (a) clinical implementation guidelines including hardware, software, and clinical indications for use, (b) commissioning and quality assurance recommendations based on early user experience, as well as guidelines on Failure Mode and Effects Analysis, and (c) a discussion of potential future developments. The deliverables from this report include: an explanation of MLC tracking and its historical development; terms and definitions relevant to MLC tracking; the clinical benefit of, clinical experience with and clinical implementation guidelines for MLC tracking; quality assurance guidelines, including example quality assurance worksheets; a clinical decision pathway, future outlook and overall recommendations.

In this chapter, small field dosimetry for two dedicated radiosurgery treatment delivery devices, the CyberKnife and the ZAP-X, are presented. After a short technical overview and introduction to the respective device, small field dosimetry beam data is discussed. For each device, the adaptation of reference dosimetry protocols for the machine-specific reference field is covered. Measurement methods to collect data for output factors, percent depth dose (PDD) or tissue-phantom ratio (TPR), and off-axis factors are presented. Suitable detectors for measuring each beam data type are listed. Sample data to visualize the specific characteristics of each beam dataset are provided. This chapter covers the difference between beam data from the fixed cones, IRIS collimator and multi-leaf collimator (M6) for the CyberKnife, including selected comparison data plots.

PURPOSE Our objective was to demonstrate the efficacy of a telehealth training course on high-dose-rate (HDR) brachytherapy for gynecologic cancer treatment for clinicians in low- and middle-income countries (LMICs) METHODS A 12-week course consisting of 16 live video sessions was offered to 10 cancer centers in the Middle East, Africa, and Nepal. A total of 46 participants joined the course, and 22 participants, on average, attended each session. Radiation oncologists and medical physicists from 11 US and international institutions prepared and provided lectures for each topic covered in the course. Confidence surveys of 15 practical competencies were administered to participants before and after the course. Competencies focused on HDR commissioning, shielding, treatment planning, radiobiology, and applicators. Pre- and post-program surveys of provider confidence, measured by 5-point Likert scale, were administered and compared. RESULTS Forty-six participants, including seven chief medical physicists, 16 senior medical physicists, five radiation oncologists, and three dosimetrists, representing nine countries attended education sessions. Reported confidence scores, both aggregate and paired, demonstrated increases in confidence in all 15 competencies. Post-curriculum score improvement was statistically significant ( P < .05) for paired respondents in 11 of 15 domains. Absolute improvements were largest for confidence in applicator commissioning (2.3 to 3.8, P = .009), treatment planning system commissioning (2.2 to 3.9, P = .0055), and commissioning an HDR machine (2.2 to 4.0, P = .0031). Overall confidence in providing HDR brachytherapy services safely and teaching other providers increased from 3.1 to 3.8 and 3.0 to 3.5, respectively. CONCLUSION A 12-week, low-cost telehealth training program on HDR brachytherapy improved confidence in treatment delivery and teaching for clinicians in 10 participating LMICs.