bluuebunny/crossref_metadata_2025_split huggingface dataset:
WE‐G‐304‐01: Introduction
Authors: Starkschall G. 
Published: June 2015

In the past few years, several high‐profile medical physicists found their positions terminated. It is a fact that no medical physics job is a sinecure, and that individuals can be terminated through no fault of their own. Medical physicists need to be prepared for such an occurrence. Termination provisions in an employment contract, whether individually negotiated or as part of an employee manual, are important, and also generally overlooked when one is going into a new job. Coupled with the fact that most states are “at‐will,” that makes for a tough position for any physicist who finds his/her position terminated.In this course, a medical physicist who is also a practicing attorney will start the discussion with a description of the various types of employment situations and employment agreements. This will be followed by two high‐profile medical physicists who had their positions terminated in recent years, who will describe their experiences, including answering such questions asHow much time were you given before termination was effective?Did you have any foreshadowing of what was coming?How did you deal with the termination?Given hindsight, what would you have done differently to mitigate the effects of your termination?During job interviews, are there ways to open closets to find the skeletons?What advice would you give medical physicists if faced with a similar situation?What can you negotiate in a termination agreement?What kinds of termination agreements could be presented?The symposium will conclude with a panel discussion.Learning Objectives:

Identify the various types of employment contracts with an emphasis on termination provisions.
Recognize the implications of non‐compete clauses in employment contracts.
Recognize the possibility of termination of employment.
Identify ways to recognize possibly poor employment situations
Identify steps that one could take to mitigate the effects of termination.
WE‐G‐304‐04: My Personal Experience
Authors: Grant W. 
Published: June 2015

In the past few years, several high‐profile medical physicists found their positions terminated. It is a fact that no medical physics job is a sinecure, and that individuals can be terminated through no fault of their own. Medical physicists need to be prepared for such an occurrence. Termination provisions in an employment contract, whether individually negotiated or as part of an employee manual, are important, and also generally overlooked when one is going into a new job. Coupled with the fact that most states are “at‐will,” that makes for a tough position for any physicist who finds his/her position terminated.In this course, a medical physicist who is also a practicing attorney will start the discussion with a description of the various types of employment situations and employment agreements. This will be followed by two high‐profile medical physicists who had their positions terminated in recent years, who will describe their experiences, including answering such questions asHow much time were you given before termination was effective?Did you have any foreshadowing of what was coming?How did you deal with the termination?Given hindsight, what would you have done differently to mitigate the effects of your termination?During job interviews, are there ways to open closets to find the skeletons?What advice would you give medical physicists if faced with a similar situation?What can you negotiate in a termination agreement?What kinds of termination agreements could be presented?The symposium will conclude with a panel discussion.Learning Objectives:

Identify the various types of employment contracts with an emphasis on termination provisions.
Recognize the implications of non‐compete clauses in employment contracts.
Recognize the possibility of termination of employment.
Identify ways to recognize possibly poor employment situations
Identify steps that one could take to mitigate the effects of termination.
WE‐G‐BRD‐05: Inline Magnetic Fields Enhance Tumor Dose for Small Lung Cancers
Authors: Oborn B , Ge Y , Hardcastle N , Metcalfe P , Keall P 
Published: June 2015

Purpose:To report on significant dose enhancement effects caused by magnetic fields aligned parallel to 6MV photon beam radiotherapy of small lung tumors. Findings are applicable to future inline MRI‐guided radiotherapy systems.Methods:9 clinical lung plans were recalculated using Monte Carlo methods and external inline (parallel to the beam direction) magnetic fields of 0.5 T, 1.0 T and 3 T were included. Three plans were 6MV 3D‐CRT and six were 6MV IMRT. The GTV's ranged from 0.8 cc to 73 cc, while the PTV ranged from 1 cc to 180 cc.Results:The inline magnetic field has a moderate impact in lung dose distributions by reducing the lateral scatter of secondary electrons and causing a small local dose increase. Superposition of multiple small beams acts to superimpose the small dose increases and can lead to significant dose enhancements, especially when the GTV is low density. Two plans with very small, low mean density GTV's (<1 cc, ρ(mean)<0.35g/cc) showed uniform increases of 16% and 23% at 1 T throughout the PTV. Three plans with moderate mean density PTV's (3–13 cc, ρ(mean)=0.58–0.67 g/cc) showed 6% mean dose enhancement at 1 T in the PTV, however not uniform throughout the GTV/PTV. Replanning would benefit these cases. The remaining 5 plans had large dense GTV's (∼ 1 g/cc) and so only a minimal (<2%) enhancement was seen. In general the mean dose enhancement at 0.5 T was 60% less than 1 T, while 5–50% higher at 3 T.Conclusions:A paradigm shift in the efficacy of small lung tumor radiotherapy is predicted with future inline MRI‐linac systems. This will be achieved by carefully taking advantage of the reduction of lateral electronic disequilibrium withing lung tissue that is induced naturally inside strong inline magnetic fields.
WE‐G‐BRB‐03: Innovating the Delivery of Radiation Therapy
Authors: Bortfeld T. 
Published: June 2015

Over the past 20 years the NIH has funded individual grants, program projects grants, and clinical trials which have been instrumental in advancing patient care. The ways that each grant mechanism lends itself to the different phases of translating research into clinical practice will be described. Major technological innovations, such as IMRT and proton therapy, have been advanced with R01‐type and P01‐type funding and will be discussed. Similarly, the role of program project grants in identifying and addressing key hypotheses on the potential of 3D conformal therapy, normal tissue‐guided dose escalation and motion management will be described. An overview will be provided regarding how these technological innovations have been applied to multi‐institutional NIH‐sponsored trials. Finally, the panel will discuss regarding which research questions should be funded by the NIH to inspire the next advances in radiation therapy.Learning Objectives:

Understand the different funding mechanisms of the NIH
Learn about research advances that have led to innovation in delivery
Review achievements due to NIH‐funded program project grants in radiotherapy over the past 20 years
Understand example advances achieved with multi‐institutional clinical trials
NIH
WE‐G‐BRA‐02: SafetyNet: Automating Radiotherapy QA with An Event Driven Framework
Authors: Hadley S , Kessler M , Litzenberg D , Lee C , Irrer J , Chen X , Acosta E , Weyburne G , Keranen W , Lam K , Covington E , Younge K , Matuszak M , Moran J 
Published: June 2015

Purpose:Quality assurance is an essential task in radiotherapy that often requires many manual tasks. We investigate the use of an event driven framework in conjunction with software agents to automate QA and eliminate wait times.Methods:An in house developed subscription‐publication service, EventNet, was added to the Aria OIS to be a message broker for critical events occurring in the OIS and software agents. Software agents operate without user intervention and perform critical QA steps. The results of the QA are documented and the resulting event is generated and passed back to EventNet. Users can subscribe to those events and receive messages based on custom filters designed to send passing or failing results to physicists or dosimetrists. Agents were developed to expedite the following QA tasks: Plan Revision, Plan 2nd Check, SRS Winston‐Lutz isocenter, Treatment History Audit, Treatment Machine Configuration.Results:Plan approval in the Aria OIS was used as the event trigger for plan revision QA and Plan 2nd check agents. The agents pulled the plan data, executed the prescribed QA, stored the results and updated EventNet for publication. The Winston Lutz agent reduced QA time from 20 minutes to 4 minutes and provided a more accurate quantitative estimate of radiation isocenter. The Treatment Machine Configuration agent automatically reports any changes to the Treatment machine or HDR unit configuration. The agents are reliable, act immediately, and execute each task identically every time.Conclusion:An event driven framework has inverted the data chase in our radiotherapy QA process. Rather than have dosimetrists and physicists push data to QA software and pull results back into the OIS, the software agents perform these steps immediately upon receiving the sentinel events from EventNet.Mr Keranen is an employee of Varian Medical Systems. Dr. Moran's institution receives research support for her effort for a linear accelerator QA project from Varian Medical Systems. Other quality projects involving her effort are funded by Blue Cross Blue Shield of Michigan, Breast Cancer Research Foundation, and the NIH.
WE‐G‐BRA‐05: IROC Houston On‐Site Audits and Parameters That Affect Performance
Authors: Kry S , Dromgoole L , Alvarez P , Lowenstein J , Molineu A , Taylor P , Followill D 
Published: June 2015

Purpose:To highlight the IROC Houston on‐site dosimetry audit program, and to investigate the impact of clinical conditions on the frequency of errors/recommendations noted by IROC Houston.Methods:The results of IROC Houston on‐site audits from 2000‐present were abstracted and compared to clinical parameters, this included 409 institutions and 1020 linacs. In particular, we investigated the frequency of recommendations versus year, and the impact of repeat visits on the number of recommendations. We also investigated the impact on the number of recommendations of several clinical parameters: the number and age of the linacs, the linac/TPS combination, and the scope of the QA program.Results:The number of recommendations per institution (3.1 average) has shown decline between 2000 and present, although the number of recommendations per machine (0.89) has not changed. Previous IROC Houston site visits did not Result in fewer recommendations on a repeat visit, but IROC Houston tests have changed substantially during the last 15 years as radiotherapy technology has changed. There was no impact on the number of recommendations based on the number of machines at the institution or the age of a given machine. The fewest recommendations were observed for Varian‐Eclipse combinations (0.71 recs/machine), while Elekta‐ Pinnacle combinations yielded the most (1.62 recs/machine). Finally, in the TG‐142 era (post‐2010), those institutions that had a QA recommendation (n=77) had significantly more other recommendations (1.83 per institution) than those that had no QA rec (n=12, 1.33 per institution).Conclusion:Establishing and maintaining a successful radiotherapy program is challenging and areas of improvement can routinely be identified. Clinical conditions such as linac‐TPS combinations and the establishment of a good QA program impact the frequency of errors/deficiencies identified by IROC Houston during their on‐site review process.
WE‐G‐BRA‐06: Application of Systems and Control Theory‐Based Hazard Analysis to Radiotherapy
Authors: Pawlicki T , Samost A , Leveson N 
Published: June 2015

Purpose:The process of delivering radiation occurs in a complex socio‐technical system heavily reliant on human operators. Furthermore, both humans and software are notoriously challenging to account for in traditional hazard analysis models. High reliability industries such as aviation have approached this problem through using hazard analysis techniques grounded in systems and control theory. The purpose of this work is to apply the Systems Theoretic Accident Model Processes (STAMP) hazard model to radiotherapy. In particular, the System‐Theoretic Process Analysis (STPA) approach is used to perform a hazard analysis of a proposed on‐line adaptive cranial radiosurgery procedure that omits the CT Simulation step and uses only CBCT for planning, localization, and treatment.Methods:The STPA procedure first requires the definition of high‐level accidents and hazards leading to those accidents. From there, hierarchical control structures were created followed by the identification and description of control actions for each control structure. Utilizing these control structures, unsafe states of each control action were created. Scenarios contributing to unsafe control action states were then identified and translated into system requirements to constrain process behavior within safe boundaries.Results:Ten control structures were created for this new CBCT‐only process which covered the areas of hospital and department management, treatment design and delivery, and vendor service. Twenty three control actions were identified that contributed to over 80 unsafe states of those control actions resulting in over 220 failure scenarios.Conclusion:The interaction of people, hardware, and software are highlighted through the STPA approach. STPA provides a hierarchical model for understanding the role of management decisions in impacting system safety so that a process design requirement can be traced back to the hazard and accident that it is intended to mitigate.Varian Medical Systems, Inc.
WE‐G‐BRA‐07: Analyzing the Safety Implications of a Brachytherapy Process Improvement Project Utilizing a Novel System‐Theory‐Based Hazard‐Analysis Technique
Authors: Tang A , Samost A , Viswanathan A , Cormack R , Damato A 
Published: June 2015

Purpose:To investigate the hazards in cervical‐cancer HDR brachytherapy using a novel hazard‐analysis technique, System Theoretic Process Analysis (STPA). The applicability and benefit of STPA to the field of radiation oncology is demonstrated.Methods:We analyzed the tandem and ring HDR procedure through observations, discussions with physicists and physicians, and the use of a previously developed process map. Controllers and their respective control actions were identified and arranged into a hierarchical control model of the system, modeling the workflow from applicator insertion through initiating treatment delivery. We then used the STPA process to identify potentially unsafe control actions. Scenarios were then generated from the identified unsafe control actions and used to develop recommendations for system safety constraints.Results:10 controllers were identified and included in the final model. From these controllers 32 potentially unsafe control actions were identified, leading to more than 120 potential accident scenarios, including both clinical errors (e.g., using outdated imaging studies for planning), and managerial‐based incidents (e.g., unsafe equipment, budget, or staffing decisions). Constraints identified from those scenarios include common themes, such as the need for appropriate feedback to give the controllers an adequate mental model to maintain safe boundaries of operations. As an example, one finding was that the likelihood of the potential accident scenario of the applicator breaking during insertion might be reduced by establishing a feedback loop of equipment‐usage metrics and equipment‐failure reports to the management controller.Conclusion:The utility of STPA in analyzing system hazards in a clinical brachytherapy system was demonstrated. This technique, rooted in system theory, identified scenarios both technical/clinical and managerial in nature. These results suggest that STPA can be successfully used to analyze safety in brachytherapy and may prove to be an alternative to other hazard analysis techniques.
WE‐G‐BRA‐09: Microsphere Brachytherapy Failure Mode and Effects Analysis in a Dual‐Vendor Environment
Authors: Younge K C , Lee C I , Feng M , Novelli P , Moran J M , Prisciandaro J I 
Published: June 2015

Purpose:To improve the safety and quality of a dual‐vendor microsphere brachytherapy program with failure mode and effects analysis (FMEA).Methods:A multidisciplinary team including physicists, dosimetrists, a radiation oncologist, an interventional radiologist, and radiation safety personnel performed an FMEA for our dual‐vendor microsphere brachytherapy program employing SIR‐Spheres (Sirtex Medical Limited, Australia) and Theraspheres (BTG, England). We developed a program process tree and step‐by‐step instructions which were used to generate a comprehensive list of failure modes. These modes were then ranked according to severity, occurrence rate, and detectability. Risk priority numbers (RPNs) were calculated by multiplying these three scores together. Three different severity scales were created: one each for harmful effects to the patient, staff, or the institution. Each failure mode was ranked on one or more of these scales.Results:The group identified 164 failure modes for the microsphere program. 113 of these were ranked using the patient severity scale, 52 using the staff severity scale, and 50 using the institution severity scale. The highest ranked items on the patient severity scale were an error in the automated dosimetry worksheet (RPN = 297.5), and the incorrect target specified on the planning study (RPN = 135). Some failure modes ranked differently between vendors, especially those corresponding to dose vial preparation because of the different methods used. Based on our findings, we made several improvements to our QA program, including documentation to easily identify which product is being used, an additional hand calculation during planning, and reorganization of QA steps before treatment delivery. We will continue to periodically review and revise the FMEA.Conclusion:We have applied FMEA to our dual‐vendor microsphere brachytherapy program to identify potential key weaknesses in the treatment chain. Our FMEA results were used to improve the effectiveness of our overall microsphere program.
WE‐G‐204‐02: Utility of a Channelized Hotelling Model Observer Over a Large Range of Angiographic Exposure Levels
Authors: Fetterly K , Favazza C 
Published: June 2015

Purpose:Mathematical model observers provide a figure of merit that simultaneously considers a test object and the contrast, noise, and spatial resolution properties of an imaging system. The purpose of this work was to investigate the utility of a channelized Hotelling model observer (CHO) to assess system performance over a large range of angiographic exposure conditions.Methods:A 4 mm diameter disk shaped, iodine contrast test object was placed on a 20 cm thick Lucite phantom and 1204 image frames were acquired using fixed x‐ray beam quality and for several detector target dose (DTD) values in the range 6 to 240 nGy. The CHO was implemented in the spatial domain utilizing 96 Gabor functions as channels. Detectability index (DI) estimates were calculated using the “resubstitution” and “holdout” methods to train the CHO. Also, DI values calculated using discrete subsets of the data were used to estimate a minimally biased DI as might be expected from an infinitely large dataset. The relationship between DI, independently measured CNR, and changes in results expected assuming a quantum limited detector were assessed over the DTD range.Results:CNR measurements demonstrated that the angiography system is not quantum limited due to relatively increasing contamination from electronic noise that reduces CNR for low DTD. Direct comparison of DI versus CNR indicates that the CHO relatively overestimates DI for low DTD and/or underestimates DI values for high DTD. The relative magnitude of the apparent bias error in the DI values was ∼20% over the 40x DTD range investigated.Conclusion:For the angiography system investigated, the CHO can provide a minimally biased figure of merit if implemented over a restricted exposure range. However, bias leads to overestimates of DI for low exposures. This work emphasizes the need to verify CHO model performance during real‐world application.
WE‐G‐207‐01: Motion‐Compensated Iterative Reconstruction of Coronary Artery Based On 3D/2D Deformable Image Registration
Authors: Liu B , Liang B , Zhou F 
Published: June 2015

Purpose:The 3D reconstruction of coronary artery from x‐ray angiograms rotationally acquired on c‐arm is a challenging task because of the vessel motion. While ECG gated reconstruction have shown promising results, residual vessel motion exists because of imperfect gating or irregular motion, and affects the reconstruction quality. The purpose of this work is to propose and validate a new motion‐compensated reconstruction method to reduce the effect of residual vessel motion.Methods:The proposed method consisted of three main steps. First, a subset of angiograms were selected using nearest‐neighbor ECG gating and used to perform the initial reconstruction based on a L1 and total variation regularized iterative reconstruction method. Due to the residual vessel motion, the initial Result exhibited motion artifacts which hindered its clinical usage. Next, a novel 3D/2D registration method was proposed to estimate the vessel motion between the initial reconstruction and the vessel morphology corresponding to each angiogram. Finally, a regularized iterative reconstruction method with motion‐compensation was proposed to reconstruct the final Result.Results:The proposed method was evaluated using three groups of simulated ECG‐gated angiograms with increasing amount of residual vessel motion. The reconstruction results of the proposed method were quantitatively evaluated using Maximum Mean Overlap (MMO) and Relative Radius Error (RRE) metrics, where larger MMO value and smaller RRE value means a better reconstruction. The MMOs (ECG gated reconstruction vs. motion‐compensated reconstruction) for the three groups were (0.94, 0.87, 0.79) vs. (0.96, 0.93, 0.89); The RREs were (7.7, 15.6, 23.3) vs. (4.2, 4.3, 7.1). The reconstruction Result was comparable to that of state‐of‐the‐art method.Conclusion:We have developed and validated a motion‐compensated reconstruction method to handle the residual vessel motion which degrades the ECG gated reconstruction. The method could effectively estimate and compensate the vessel motion, and thus improve the reconstruction quality.