A systems theory-based safety assessment of pre-treatment patient-specific quality assurance for intensity-modulated treatments in a single-vendor environment.

BACKGROUND AND PURPOSE: While patient-specific quality assurance (PSQA) has been integral to intensity-modulated treatments, its value is debated. A systems approach to safety is essential for understanding complex systems like radiation oncology but is often overlooked in PSQA research. This study aims to elucidate PSQA's fundamental value and identify opportunities for enhancing safety in intensity-modulated treatments. MATERIALS AND METHODS: First, causal scenarios that could lead to patient harm were identified using a prospective safety assessment technique developed for complex systems. Second, PSQA's ability to mitigate these scenarios was evaluated using standard stability and control principles. The analysis also included safeguards related to PSQA, such as daily linac QA, equipment commissioning, and equipment design. RESULTS: Ten causal scenarios were identified, highlighting well-known issues like flawed algorithms, data corruption, and hardware errors. Mitigation is achieved through advanced dose calculation and optimization algorithms, software and data integration, and preconfigured beam data, which improve decision-making and system state determination. Modern linac control systems enhance all aspects of system stability and control. Commissioning, daily linac QA, and PSQA are effective in enhancing the determination of system states only when feedback is non-overlapping and unambiguous. CONCLUSION: Given equipment improvement and related safeguards, the feedback generated from PSQA has diminished in value. To better complement other safeguards, PSQA should evolve to provide automated, unambiguous detection of any potential catastrophic treatment deviations prior to treatment. This evolution would allow physicists to focus on more critical aspects of patient care in radiation oncology.

AAPM task group report 288: Recommendations for guiding radiotherapy event narratives.

Incident reporting and learning systems provide an opportunity to identify systemic vulnerabilities that contribute to incidents and potentially degrade quality. The narrative of an incident is intended to provide a clear, easy to understand description of an incident. Unclear, incomplete or poorly organized narratives compromise the ability to learn from them. This report provides guidance for drafting effective narratives, with particular attention to the use of narratives in incident reporting and learning systems (IRLS). Examples are given that compare effective and less than effective narratives. This report is mostly directed to organizations that maintain IRLS, but also may be helpful for individuals who desire to write a useful narrative for entry into such a system. Recommendations include the following: (1) Systems should allow a one- or two-sentence, free-text synopsis of an incident without guessing at causes; (2) Information included should form a sequence of events with chronology; and (3) Reporting and learning systems should consider using the headings suggested to guide the reporter through the narrative: (a) incident occurrences and actions by role; (b) prior circumstances and actions; (c) method by which the incident was identified; (d) equipment related details if relevant; (e) recovery actions by role; (f) relevant time span between responses; (g) and how individuals affected during or immediately after incident. When possible and appropriate, supplementary information including relevant data elements should be included using numerical scales or drop-down choices outside of the narrative. Information that should not be included in the narrative includes: (a) patient health information (PHI); (b) conjecture or blame; (c) jargon abbreviations or details without specifying their significance; (d) causal analysis.

Safety and Efficiency Analysis of Operational Decision-Making During Cone Beam Computed Tomography-Based Online Adaptive Radiation Therapy.

PURPOSE: Cone beam computed tomography (CBCT)-based online adaptive radiation therapy (ART) is especially beneficial for patients with large interfractional anatomic changes. However, treatment planning and review decisions need to be made at the treatment console in real-time and may be delegated to clinical staff whose conventional scope of practice does not include making such decisions. Therefore, implementation can create new safety risks and inefficiencies. The objective of this work is to systematically analyze the safety and efficiency implications of human decision-making during the treatment session for CBCT-based online ART. METHODS AND MATERIALS: The analysis was performed by applying the Systems-Theoretical Process Analysis technique and its extension for human decision-making. Four centers of different CBCT-based online ART practice models comprised the analysis team. RESULTS: The general radiation therapy control structure was refined to model the interactions between routine treatment delivery staff and in-person or remote support staff. The treatment delivery staff perform 6 key control actions. Eighteen undesirable states of those control actions were identified as affecting safety and/or efficiency. In turn, 97 hazardous clinical scenarios were identified, with the control action "prepare and position patient" having the least number of scenarios and "delineate/edit influencer and target structures" having the most. Five of these are specific to either in-person or remote support during the treatment session, and 12 arise from staff support in general. CONCLUSIONS: An optimally safe and efficient online ART program should require little to no support staff at the treatment console to reduce staff coordination. Uptraining of the staff already at the treatment console is needed to achieve this goal. Beyond the essential knowledge and skills such as contour editing and the selection of an optimal plan, uptraining should also target the specific cognitive biases identified in this work and the cognitive strategies to overcome these biases. Additionally, technological and organizational changes are necessary.

Facilitating the application of systems-theoretic process analysis in healthcare: Creating control structures using process maps.

Systems-theoretic process analysis (STPA) is a prospective safety assessment tool increasingly applied in healthcare. A problem hampering STPA proliferation is the difficulty of modeling systems for analysis by creating control structures. In this work, a method is proposed to use existing process maps-commonly available in healthcare-when creating a control structure. The proposed method entails (1) extract information from the process map, (2) determine the modeling boundary of the control structure, (3) transfer the extracted information to the control structure, (4) add additional information to complete the control structure. Two case studies were conducted: (1) ambulance patient offloading in the emergency department and (2) ischemic stroke care with intravenous thrombolysis. The amount of process map-derived information in the control structures was quantified. On average, 68% of the information in the final control structures was derived from the process map. Additional control actions and feedback were added from nonprocess map sources for management and frontline controllers. Despite the differences between process maps and control structures, much of the information in a process map can be used when creating a control structure. The method enables the creation of a control structure from a process map to be done in a structured fashion.

Examining the Effect of Direct Patient Care for Medical Physicists: A Randomized Prospective Phase III Trial.

PURPOSE: Our purpose was to investigate the effect of physicist-patient consults on patient anxiety and patient satisfaction with a randomized prospective phase III clinical trial. METHODS AND MATERIALS: Sixty-six patients were randomly assigned to the physics direct patient care (PDPC) arm or the control arm of the trial. Patients assigned to the PDPC arm received 2 physicist-patient consults to educate them on the technical aspects of their radiation therapy, while patients assigned to the control arm received the standard of care (ie, standard radiation therapy workflow without any additional physicist-patient consults). Questionnaires were administered to all patients at 4 time points (after enrollment, after the simulation, after the first treatment, and after the last treatment) to assess anxiety and satisfaction. RESULTS: The decrease in anxiety for the PDPC arm, compared with the control arm, was statistically significant at the first treatment (P = .027) time point. The increase in technical satisfaction for the PDPC arm, compared with the control arm, was statistically significant at the simulation (P = .005), first treatment (P < .001), and last treatment (P = .002) time points. The increase in overall satisfaction for the PDPC arm, compared with the control arm, was statistically significant at the first treatment (P = .014) and last treatment (P = .001) time points. CONCLUSIONS: Physicist-patient consults improved the patient experience by decreasing anxiety and increasing satisfaction. Future work is needed to modify current radiation oncology workflows and medical physics responsibilities to allow all patients to benefit from this advancement in patient care.

A system-based operational assessment of external beam radiotherapy.

PURPOSE: Advanced technologies have led to improvements in modern radiotherapy over the years. However, adoption of advanced technologies can present challenges to existing clinical operations and negatively impact safety. The purpose of this work is to perform an assessment of modern radiotherapy for the operational objectives of safety, efficiency, and financial viability. METHODS: This work focuses on external beam radiotherapy (EBRT). The operational assessment included department management, treatment planning, treatment delivery, and associated workflows for three equipment configurations of Ethos, Halcyon, and TrueBeam with the ARIA information system, Eclipse treatment planning, and IDENTIFY surface guidance. Systems-theoretic process analysis (STPA) was used to analyze the related workflows. Control actions, unsafe contexts of those control actions, and associated causal scenarios that can lead to unsafe radiation and non-radiation physical injury (safety objective), reduced treatment capacity (efficiency objective), and costs that exceed budget (financial viability objective) were identified. RESULTS: The number of control actions (and causal scenarios) were 18 (254), 18 (267), and 20 (267) for the equipment configurations of Halcyon, TrueBeam, and Ethos, respectively. The extent that safety, efficiency, and financial viability were impacted is similar across the different equipment configurations, but there were some noteworthy differences related to information transfer and workflow bottlenecks potentially impacting access to care. Seventy-five percent of the scenarios across all three configurations were related to safety. Overall, 29% of the scenarios impacted more than one operational objective and 48% were related to human decisions during the process of care. Planned or unplanned process changes were responsible for 8% of the causal scenarios. CONCLUSIONS: Broad-based clinical improvements may be realized by addressing causal scenarios that impact multiple objectives. Redesigning the roles and responsibilities of the clinical team and some aspects of the radiotherapy workflow may be helpful to fully realize the benefits of advanced technologies. Radiotherapy may benefit from additional tools to improve the consistency between decisions and actions when system or process changes occur.

Quality and Safety Considerations in Stereotactic Radiosurgery and Stereotactic Body Radiation Therapy: An ASTRO Safety White Paper Update.

PURPOSE: This updated report on stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) is part of a series of consensus-based white papers previously published addressing patient safety. Since the first white papers were published, SRS and SBRT technology and procedures have progressed significantly such that these procedures are now more commonly used. The complexity and submillimeter accuracy, and delivery of a higher dose per fraction requires an emphasis on best practices for technical, dosimetric, and quality assurance. Therefore, quality and patient safety considerations for these techniques remain an important area of focus. METHOD: The American Society for Radiation Oncology convened a task force to assess the original SRS/SBRT white paper and update content where appropriate. Recommendations were created using a consensus-building methodology and task force members indicated their level of agreement based on a 5-point Likert scale, from "strongly agree" to "strongly disagree." A prespecified threshold of ≥75% of raters who select "strongly agree" or "agree" indicated consensus. SUMMARY: This white paper builds on the previous version and uses of other guidance documents to broadly address SRS and SBRT delivery, primarily focusing on processes related to quality and safety. SRS and SBRT require a team-based approach, staffed by appropriately trained and credentialed specialists as well as significant personnel resources, specialized technology, and implementation time. A thorough feasibility analysis of resources is required to achieve the clinical and technical goals and thoroughly discussed with all personnel before undertaking new disease sites. A comprehensive quality assurance program must be developed, using established treatment guidelines, to ensure SRS and SBRT are performed in a safe and effective manner. Patient safety in SRS/SBRT is everyone's responsibility and professional organizations, regulators, vendors, and end-users must demonstrate a clear commitment to working together to ensure the highest levels of safety.

AAPM task group report 302: Surface-guided radiotherapy.

The clinical use of surface imaging has increased dramatically, with demonstrated utility for initial patient positioning, real-time motion monitoring, and beam gating in a variety of anatomical sites. The Therapy Physics Subcommittee and the Imaging for Treatment Verification Working Group of the American Association of Physicists in Medicine commissioned Task Group 302 to review the current clinical uses of surface imaging and emerging clinical applications. The specific charge of this task group was to provide technical guidelines for clinical indications of use for general positioning, breast deep-inspiration breath hold treatment, and frameless stereotactic radiosurgery. Additionally, the task group was charged with providing commissioning and on-going quality assurance (QA) requirements for surface-guided radiation therapy (SGRT) as part of a comprehensive QA program including risk assessment. Workflow considerations for other anatomic sites and for computed tomography simulation, including motion management, are also discussed. Finally, developing clinical applications, such as stereotactic body radiotherapy (SBRT) or proton radiotherapy, are presented. The recommendations made in this report, which are summarized at the end of the report, are applicable to all video-based SGRT systems available at the time of writing.

Operational Insights From the Longitudinal Analysis of a Linear Accelerator Machine Log.

Purpose This study aimed to perform a longitudinal analysis of linear accelerator (linac) technical faults reported with a cloud-based Machine Log system in use in a busy academic clinic and derive operational insights related to linac reliability, clinical utilization, and performance. Methods We queried the Machine Log system for the following parameters: linac type, number of reported technical faults, types of fault, number of faults where the linac was disabled, and estimated clinical downtime. The number of fractions treated and monitor units (MU) delivered were obtained from the record and verify system as metrics of linac utilization and to normalize the number of reported linac faults, facilitating inter-comparison. Two Varian TrueBeam C-arm linacs (Varian Medical Systems, Palo Alto, CA), one Varian 21iX C-arm linac (Varian Medical Systems, Palo Alto, CA), and one newly installed Varian Halcyon ring gantry linac (Varian Medical Systems, Palo Alto, CA) were evaluated. The linacs were studied over a 30-month period from September 2017 to March 2020.  Results Over 30 months, comprising 677 clinical days, 1234 faults were reported from all linacs, including 153 "linac down" events requiring rescheduling or cancellation of treatments. The TrueBeam linacs reported nearly twice as many imaging, multileaf collimator (MLC), and beam generation faults per fraction, and MU as the Halcyon. Halcyon experienced fewer beam generation/steering, accessory, and cooling-related faults than the other linacs but reported more computer and networking issues. Although it employs a relatively new MLC design compared to the C-arm linacs and delivers primarily intensity-modulated treatments, Halcyon reported fewer MLC faults than the other linacs. The 21iX linac had the fewest software-related faults but was subject to the most cooling-related faults, which we attributed to extensive use of this linac for treatment techniques with extended beam-on times. Conclusions A longitudinal analysis of a cloud-based Machine Log system yielded operational insights into the utilization, performance, and technical reliability of the linacs in use at our institution. Several trends in linac sub-system reliability were identified and could be attributed to either age, design, clinical use, or operational demands. The results of this analysis will be used as a basis for designing linac quality assurance schedules that reflect actual linac usage and observed sub-system reliability. Such a practice may contribute to a clinic workflow subject to fewer disruptions from linac faults, ultimately improving efficiency and patient safety.

A Blinded, Prospective Study of Error Detection During Physician Chart Rounds in Radiation Oncology.

PURPOSE: Peer review during physician chart rounds is a major quality assurance and patient safety step in radiation oncology. However, the effectiveness of chart rounds in detecting problematic treatment plans is unknown. We performed a prospective blinded study of error detection at chart rounds to clarify the effectiveness of this quality assurance step. METHODS AND MATERIALS: Radiation Oncology Incident Learning System publications were queried for problematic plans approved for treatment that would be detectable at chart rounds. A resident physician, physicist, and dosimetrist collaboratively generated 20 treatment plans with simulated errors identical in nature to those reported to the Radiation Oncology Incident Learning System. These were inserted randomly into weekly chart rounds over 9 weeks, with a median of 2 problematic plans presented per chart rounds (range, 1-4). Data were collected on detection, attendance, length, and number of cases presented at chart rounds. Data were analyzed using descriptive statistics and univariable logistic regression with odds ratios. RESULTS: The median length of chart rounds over the study period was 60 minutes (range, 42-79); median number of cases presented per chart rounds was 45 (range, 38-50). The overall detection rate was 55% (11 of 20). Detection rates were higher for cases presented earlier in chart rounds: 75% versus 25% of problematic plans were detected within 30 minutes of start of chart rounds versus after 30 minutes (odds ratio, 0.11; 95% confidence interval, 0.01-0.88; P = .037). Detection rates showed a trend toward increase during the study period but this was not significant: 33% in weeks 1 to 5 and 73% during weeks 6 to 9 (5.3; 95% confidence interval, 0.78-36; P = .08). CONCLUSIONS: The detection of clinically significant problematic plans during chart rounds could be significantly improved. Problematic plans are more frequently detected earlier in chart rounds and inserting such plans into chart rounds may enhance detection; however, larger studies are needed to confirm these findings. A multi-institutional study is planned.

Evaluation of a Patient Communication Skills Training Program for Medical Physicists.

PURPOSE: To evaluate the efficacy of a training program designed to teach medical physicists how to communicate with patients effectively in the clinical environment. METHODS AND MATERIALS: The training program was offered 3 times between 2016 and 2019. Participants were asked to rank their level of confidence in 5 categories relevant to patient communication on a 5-point Likert scale at 3 separate time points over the course of the training program. Participants were also asked to provide written responses to 5 common questions from patients at 2 separate time points, and these responses were numerically scored using the Constant Comparative Method. Competency in patient communication was assessed during simulated patient consults using a 9-element clinical competency assessment form. Changes in participants' stated level of confidence over the course of the training program and differences between faculty and residents were analyzed using the Student t test, and participants' scored responses to common questions were analyzed using analysis of variance. RESULTS: Fifteen medical physicists participated in the training program: 6 resident physicists (4 first year and 2 second year) and 9 faculty physicists. Mean participant-stated level of confidence increased significantly across all categories (P < .05) between the first and second training intervention and between the second and third training intervention. There was no significant difference in mean participant-stated level of confidence between faculty and resident medical physicists. We observed statistically significant improvements in scored responses to common patient questions between the 2 assessment time points (P < .05). Of the 15 participants, 14 met competency assessment goals during simulated patient consults. CONCLUSIONS: The patient communication skills training program increases medical physicists' level of confidence across 5 patient communication categories and improves their responses to common questions from patients. In addition, the program can discern differences in communication competency between physicists.

Prevalence of software alerts in radiotherapy.

Radiotherapy software messages (sometimes called alerts, pop-up windows, alarms, or error messages) to the user appear continuously on computer screens. These software messages sometimes require decisions to be made as to the next appropriate action. However, mainly these messages are for information only. Dealing with software messages is a well-recognized problem in healthcare and has contributed to catastrophic events both outside and within radiotherapy. The purpose of this work is to highlight the prevalence and raise awareness within the radiotherapy community of such software messages related to external beam radiation therapy procedures at the linear accelerator. Radiation Therapists (RTTs) were asked to record the type and frequency of software message over 50 fractions and for 50 different patients. The data was collected at 6 institutions in the Netherlands using linear accelerators from Elekta, Ltd. and Varian Medical Systems, Inc. Results show that linear accelerator software messages (including record and verify) occur at a rate of about 8.9 messages per patient fraction. This number of software messages is potentially impacting on patient safety as these messages range in level of importance. The impact and potential reduction of these software messages should be the focus of future research and improved implementation.

A review of patient questions from physicist-patient consults.

PURPOSE: To provide insight into the types of questions asked to medical physicists by patients during one-on-one physicist-patient consults at one institution. MATERIALS AND METHODS: Medical physicists trained in patient communication techniques met with patients to provide an overview of the treatment planning and delivery processes, discuss the patient's treatment plan, and answer any technical questions. From August 2016 to December 2019, 152 physicist-patient consults were conducted. In the initial months of the study (August 2016-December 2017), following each physicist-patient consult, all patient questions were documented by the physicists. For the remaining time period (January 2018-December 2019), any newly encountered questions were periodically added to the list. The questions were compiled into a comprehensive list and organized into categories. RESULTS: There were a total of 88 unique patient questions. These questions fit into four topical categories. Fifty-four questions (61.4%) were in the "Treatment Planning and Delivery Questions" category, 15 questions (17.1%) were in the "General Radiation Questions or Concerns" category, 13 questions (14.8%) were in the "Safety and Quality Assurance Questions" category, and 6 questions (6.8%) were in the "Medical Questions" category. Overall, patients were primarily concerned about how radiation works, the treatment planning and delivery processes, and what is being done to keep them safe throughout their treatment. CONCLUSION: Physicist-patient consults provided an opportunity to address the technical aspects of radiation therapy with patients in greater detail. The fact that patient questions could be conveniently grouped into only four topical categories indicates that it may be straightforward for other medical physicists to prepare for effectively addressing technical questions during physicist-patient consults.

Three-dimensional printing in radiation oncology: A systematic review of the literature.

PURPOSE/OBJECTIVES: Three-dimensional (3D) printing is recognized as an effective clinical and educational tool in procedurally intensive specialties. However, it has a nascent role in radiation oncology. The goal of this investigation is to clarify the extent to which 3D printing applications are currently being used in radiation oncology through a systematic review of the literature. MATERIALS/METHODS: A search protocol was defined according to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Included articles were evaluated using parameters of interest including: year and country of publication, experimental design, sample size for clinical studies, radiation oncology topic, reported outcomes, and implementation barriers or safety concerns. RESULTS: One hundred and three publications from 2012 to 2019 met inclusion criteria. The most commonly described 3D printing applications included quality assurance phantoms (26%), brachytherapy applicators (20%), bolus (17%), preclinical animal irradiation (10%), compensators (7%), and immobilization devices (5%). Most studies were preclinical feasibility studies (63%), with few clinical investigations such as case reports or series (13%) or cohort studies (11%). The most common applications evaluated within clinical settings included brachytherapy applicators (44%) and bolus (28%). Sample sizes for clinical investigations were small (median 10, range 1-42). A minority of articles described basic or translational research (11%) and workflow or cost evaluation studies (3%). The number of articles increased over time (P < 0.0001). While outcomes were heterogeneous, most studies reported successful implementation of accurate and cost-effective 3D printing methods. CONCLUSIONS: Three-dimensional printing is rapidly growing in radiation oncology and has been implemented effectively in a diverse array of applications. Although the number of 3D printing publications has steadily risen, the majority of current reports are preclinical in nature and the few clinical studies that do exist report on small sample sizes. Further dissemination of ongoing investigations describing the clinical application of developed 3D printing technologies in larger cohorts is warranted.

Implementation of peer-review quality rounds for gynecologic brachytherapy in a high-volume academic center.

PURPOSE: While peer review is critical for quality and safety in radiotherapy, there are neither formal guidelines nor format examples for brachytherapy (BT) peer review. We report on a gynecologic BT peer-review method implemented at a high-volume academic center. METHODS AND MATERIALS: We analyzed discussions at bimonthly gynecologic BT peer-review rounds between July and December 2018. Rounds consisted of 2-5 attending physicians with gynecologic BT expertise, 1-2 BT physicists, and trainees. Peer-review targets included clinical case review, contours, implant technique, dose/fractionation, and target/organ-at-risk (OAR) dosimetry. The projected/final target and OAR dosimetry were analyzed. RESULTS: 55 separate implants from 44 patients were reviewed. Implants were mostly reviewed after the first BT fraction (n = 16, 29%) or at another time point during BT (n = 20, 36%). One (2%) implant was presented prospectively. The applicator type and BT technique were reviewed for all implants. Dose/fractionation was evaluated for 46 implants (84%); contours were discussed for 21 (38%). Target and OAR dosimetry were reviewed for 54 (98%) and 28 implants (51%), respectively. Six cases (11%) underwent minor changes to the applicator type to improve target and/or OAR dosimetry. One case (2%) had a major change recommended to the dose/fractionation. CONCLUSIONS: Gynecologic BT peer review may enhance BT quality by allowing for implant optimization and formal review of challenging cases, ultimately improving medical decision-making and team communication. Peer review should be implemented in centers offering gynecologic BT.

Assessment of the use of different imaging and delivery techniques for cranial treatments on the Halcyon linac.

PURPOSE: In this work, we investigated the effect on the workflow and setup accuracy of using surface guided radiation therapy (SGRT) for patient setup, megavoltage cone beam CT (MVCBCT) or kilovoltage cone beam CT (kVCBCT) for imaging and fixed IMRT or volumetric-modulated arc therapy (VMAT) for treatment delivery with the Halcyon linac. METHODS: We performed a retrospective investigation of 272 treatment fractions, using three different workflows. The first and second workflows used MVCBCT and fixed IMRT for imaging and treatment delivery, and the second one also used SGRT for patient setup. The third workflow used SGRT for setup, kVCBCT for imaging and VMAT for delivery. Workflows were evaluated by comparing the number of fractions requiring repeated imaging acquisitions and the time required for setup, imaging and treatment delivery. Setup position accuracy was assessed by comparing the daily kV- or MV- CBCT with the planning CT and measuring the residual rotational errors for pitch, yaw and roll angles. RESULTS: Without the use of SGRT, the imaging fields were delivered more than once on 11.1% of the fractions, while re-imaging was necessary in 5.5% of the fractions using SGRT. The total treatment time, including setup, imaging, and delivery, for the three workflows was 531 ± 157 s, 503 ± 130 s and 457 ± 91 s, respectively. A statistically significant difference was observed when comparing the third workflow with the first two. The total residual rotational errors were 1.96 ± 1.29°, 1.28 ± 0.67° and 1.22 ± 0.76° and statistically significant differences were observed when comparing workflows with and without SGRT. CONCLUSIONS: The use of SGRT allowed for a reduction of re-imaging during patient setup and improved patient position accuracy by reducing residual rotational errors. A reduction in treatment time using kVCBCT with SGRT was observed. The most efficient workflow was the one including kVCBCT and SGRT for setup and VMAT for delivery.