bluuebunny/crossref_metadata_2025 huggingface dataset:
MO‐AB‐210‐03: Workshop
Authors: Lu Z.
Published: June 2015

The goal of this ultrasound hands‐on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound.

HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well‐defined regions of necrosis. This completely non‐invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands‐on demonstrations with on‐site instructors at separate stations.

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands‐on environment with live demonstrations of the techniques.

Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high‐intensity focused ultrasound and in diagnostic ultrasound QC.

Learning Objectives:

Learn ultrasound physics and safety for HIFU applications through live demonstrations

Get an overview of the state‐of‐the art in HIFU technologies and equipment

Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging

Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools

List of supporting vendors for HIFU and diagnostic ultrasound QC hands‐on workshop:

Philips Healthcare

Alpinion Medical Systems

Verasonics, Inc

Zonare Medical Systems, Inc

Computerized Imaging Reference Systems (CIRS), Inc.

GAMMEX, Inc.,

Cablon Medical BV

Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS080949 and Philips Healthcare research grant C32
MO‐B‐213‐00: AAPM Professional Liability Insurance Update
Authors: Jordan David
Published: June 2015

The AAPM Professional Liability Insurance program provides a unique ability for medical physicists to obtain liability coverage for risks arising from the practice of medical physics. In 2015, the program introduces a new occurrence‐form coverage option which has important cost and functional differences from the existing claims‐made coverage. Since both forms will be offered to new and renewing policy holders, the details and implications of these two options will be explained. A brief history of the program will be given to review the collaboration between AAPM and its insurance company partners that established and maintains the program that is available today. The future outlook of the program will include an overview of threats and opportunities that affect AAPM members’ ability to obtain cost‐effective coverage in the future.

Learning Objectives:

Gain understanding of the professional liability insurance program offered to AAPM members

Gain understanding of the difference between claims‐made form and occurrence form of coverage

Gain understanding of the role of AAPM in operating the professional liability insurance program

Graham Fuller is an employee of Mercer Consumer which is the broker and administrator of the AAPM Professional Liability Insurance program.
MO‐B‐213‐01: New Coverage Options in the AAPM Professional Liability Insurance Program
Authors: Orfali A.
Published: June 2015

The AAPM Professional Liability Insurance program provides a unique ability for medical physicists to obtain liability coverage for risks arising from the practice of medical physics. In 2015, the program introduces a new occurrence‐form coverage option which has important cost and functional differences from the existing claims‐made coverage. Since both forms will be offered to new and renewing policy holders, the details and implications of these two options will be explained. A brief history of the program will be given to review the collaboration between AAPM and its insurance company partners that established and maintains the program that is available today. The future outlook of the program will include an overview of threats and opportunities that affect AAPM members’ ability to obtain cost‐effective coverage in the future.

Learning Objectives:

Gain understanding of the professional liability insurance program offered to AAPM members

Gain understanding of the difference between claims‐made form and occurrence form of coverage

Gain understanding of the role of AAPM in operating the professional liability insurance program

Graham Fuller is an employee of Mercer Consumer which is the broker and administrator of the AAPM Professional Liability Insurance program.
MO‐B‐304‐02: Preparing a Manuscript for the JACMP
Authors: Starkschall G.
Published: June 2015

The JACMP began publication in February, 2000 and is the world's oldest open‐access medical specialty journal. Today it publishes about 200 articles in six issues annually. The JACMP archive experiences about 400,000.pdf downloads annually and a typical JACMP.pdf article is downloaded about 600 or 700 times during the first year after publication. Anyone with web access can reach these articles, having wide distribution and benefiting as many patients as possible.

Preparing a manuscript for publication in the JACMP (or any other journal) is a straightforward process. The primary purpose of a manuscript is to communicate knowledge and experience. A relatively fixed format has been developed to meet this goal; this format consists of an Abstract, Introduction, Methods and Materials, Results, and Conclusions. In addition to fitting your experience into that format, it is important to recognize your audience and direct your manuscript to that audience. Finally, it is important to write your manuscript in clear English, enlisting the aid of a copyeditor, if such an individual is available.

Reviewing the articles submitted to JACMP is a rewarding yet difficult task. A reviewer must evaluate submitted articles critically, objectively, and express opinions diplomatically regarding work presented to the journal. A perspective from a JACMP section editor and experienced reviewer will describe the key points that progress a journal article to publication. As a reviewer, the difficulties experienced as a reviewer such as an incomplete or incorrect citations, incorrect formats, etc. will also be described.

Learning Objectives:

Attendees will learn the history and philosophy behind the development of the Journal of Applied Clinical Medical Physics.

After attending this presentation, the participant will be able to prepare a well‐written manuscript suitable for publication in the JACMP or any other peer‐reviewed journal.

Attendees will learn what typical submission mistakes and difficulties are from the perspective of a section editor and experienced article reviewer.
MO‐B‐BRB‐03: Systems Engineering Tools for Treatment Planning Process Optimization in Radiation Medicine
Authors: Kapur A.
Published: June 2015

The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image‐guided‐radiation‐therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality.

In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include:

Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS.

Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process

Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning

Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment.

Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi‐automatic plan evaluation, (e) quality checklist for error prevention, (f) iterative process, (g) balance of speed and quality

Learning Objectives:

Gain familiarity with the workflow of modern treatment planning process.

Understand the scope and challenges of managing modern treatment planning processes.

Gain familiarity with Lean Six Sigma approaches and their implementation in the treatment planning workflow.
MO‐D‐213‐03: An Innovative Solution for Data Aggregation and Collection to Improve Quality of Peer Review Using a Cloud Based Platform Within a Large Oncology Network
Authors: Limmer J , De Jesus A , Henrich D , Henrich T , Kasturi T , Gogineni K
Published: June 2015

Purpose:

Introduce a cloud‐based platform in a large multi‐site Oncology network which allows for the capture of empirical data, in aggregate, across multiple sites for the purpose of process standardization and metrics reporting as a pathway for physician and physicist peer review.

Methods:

The cloud‐based system stores site profiles, technical elements, and patient specific clinical elements for each facility in the peer review process. A total of 137 sites across 17 states were added including basic site info, staffing, and equipment infrastructure in order to prepare the portal for peer review data collection. Evaluation elements specific to oncology peer review were determined at onset. Physician and Physicist quality team meetings were held to define and approve the quality elements used in the peer review portal based on professional society guidelines and best practices. A total of 407 evaluation elements were included for Physician and Physicist evaluation (129, 278 respectively). The combined evaluation elements were defined into 17 main categories and drilled down further to 106 sub categories.

Results:

13 Physician and Physicist Peer reviews were analyzed at 9 locations for purposes of this abstract. These included a mixture of overall program related and specific patient chart focused reviews. 1923 evaluation elements were answered by a total of 9 Physician and Physicist reviewers (3, 6 respectively). Recommendations were selected on a scaled approach. General recommendation, Minor Recommendation and Major Recommendation were documented on an indicator of severity while Commendation was used to document findings of exceptional attributes in care.

Conclusion:

Using a cloud‐based platform is a valuable solution to resolve the issues that have inundated peer review issues of the past. Technology combined with strategic vision will change the future of peer review to administer standardization and predictive analytics throughout an entire network to raise the level of quality patient care.
MO‐D‐213‐06: Quantitative Image Quality Metrics Are for Physicists, Not Radiologists: How to Communicate to Your Radiologists Using Their Language
Authors: Szczykutowicz T , Rubert N , Ranallo F
Published: June 2015

Purpose:

A framework for explaining differences in image quality to non‐technical audiences in medial imaging is needed. Currently, this task is something that is learned “on the job.” The lack of a formal methodology for communicating optimal acquisition parameters into the clinic effectively mitigates many technological advances. As a community, medical physicists need to be held responsible for not only advancing image science, but also for ensuring its proper use in the clinic. This work outlines a framework that bridges the gap between the results from quantitative image quality metrics like detectability, MTF, and NPS and their effect on specific anatomical structures present in diagnostic imaging tasks.

Methods:

Specific structures of clinical importance were identified for a body, an extremity, a chest, and a temporal bone protocol. Using these structures, quantitative metrics were used to identify the parameter space that should yield optimal image quality constrained within the confines of clinical logistics and dose considerations. The reading room workflow for presenting the proposed changes for imaging each of these structures is presented. The workflow consists of displaying images for physician review consisting of different combinations of acquisition parameters guided by quantitative metrics. Examples of using detectability index, MTF, NPS, noise and noise non‐uniformity are provided. During review, the physician was forced to judge the image quality solely on those features they need for diagnosis, not on the overall “look” of the image.

Results:

We found that in many cases, use of this framework settled mis‐agreements between physicians. Once forced to judge images on the ability to detect specific structures inter reader agreement was obtained.

Conclusion:

This framework will provide consulting, research/industrial, or in‐house physicists with clinically relevant imaging tasks to guide reading room image review. This framework avoids use of the overall “look” or “feel” to dictate acquisition parameter selection.

Equipment grants GE Healthcare
MO‐D‐213‐08: Remote Dosimetric Credentialing for Clinical Trials with the Virtual EPID Standard Phantom Audit (VESPA)
Authors: Lehmann J , Miri N , Vial P , Hatton J , Zwan B , Craig A , Beenstock V , Molloy T , Sloan K , Greer P
Published: June 2015

Purpose:

Report on implementation of a Virtual EPID Standard Phantom Audit (VESPA) for IMRT to support credentialing of facilities for clinical trials. Data is acquired by local facility staff and transferred electronically. Analysis is performed centrally.

Methods:

VESPA is based on published methods and a clinically established IMRT QA procedure, here extended to multi‐vendor equipment. Facilities, provided with web‐based comprehensive instructions and CT datasets, create IMRT treatment plans. They deliver the treatments directly to their EPID without phantom or couch in the beam. They also deliver a set of simple calibration fields. Collected EPID images are uploaded electronically. In the analysis, the dose is projected back into a virtual phantom and 3D gamma analysis is performed. 2D dose planes and linear dose profiles can be analysed when needed for clarification.

Results:

Pilot facilities covering a range of planning and delivery systems have performed data acquisition and upload successfully. Analysis showed agreement comparable to local experience with the method. Advantages of VESPA are (1) fast turnaround mainly driven by the facility's capability to provide the requested EPID images, (2) the possibility for facilities performing the audit in parallel, as there is no need to wait for a phantom, (3) simple and efficient credentialing for international facilities, (4) a large set of data points, and (5) a reduced impact on resources and environment as there is no need to transport heavy phantoms or audit staff. Limitations of the current implementation of VESPA for trials credentialing are that it does not provide absolute dosimetry, therefore a Level 1 audit still required, and that it relies on correctly delivered open calibration fields, which are used for system calibration.

Conclusion:

The implemented EPID based IMRT audit system promises to dramatically improve credentialing efficiency for clinical trials and wider applications. VESPA for VMAT will follow soon.
MO‐DE‐304‐02: Diagnostic Workforce Subcommittee Status and Direction
Authors: Gress D.
Published: June 2015

The Abt study of medical physicist work values for radiation oncology physics services, Round IV is completed. It supersedes the Abt III study of 2008. The 2015 Abt study measured qualified medical physicist (QMP) work associated with routine radiation oncology procedures as well as some special procedures. As before, a work model was created to allow the medical physicist to defend QMP work based on both routine and special procedures service mix. The work model can be used to develop a cost justification report for setting charges for radiation oncology physics services. The Abt study Round IV was designed to empower the medical physicist to negotiate a service or employment contract with providers based on measured national QMP workforce and staffing data.

For a variety of reasons, the diagnostic imaging contingent of AAPM has had a more difficult time trying estimate workforce requirements than their therapy counterparts. Over the past several years, the Diagnostic Work and Workforce Study Subcommittee (DWWSS) has collected survey data from AAPM members, but the data have been very difficult to interpret. The DWWSS has reached out to include more AAPM volunteers to create a more full and accurate representation of actual clinical practice models on the subcommittee. Though much work remains, through hours of discussion and brainstorming, the DWWSS has somewhat of a clear path forward. This talk will provide attendees with an update on the efforts of the subcommittee.

Learning Objectives:

Understand the new information documented in the Abt studies.

Understand how to use the Abt studies to justify medical physicist staffing.

Learn relevant historical information on imaging physicist workforce.

Understand the process of the DWWSS in 2014.

Understand the intended path forward for the DWWSS.
MO‐D‐BRD‐02: Radiological Physics and Surface Lesion Treatments with Electronic Brachytherapy
Authors: Fulkerson R.
Published: June 2015

Electronic brachytherapy (eBT) has seen an insurgence of manufacturers entering the US market for use in radiation therapy. In addition to the established interstitial, intraluminary, and intracavitary applications of eBT, many centers are now using eBT to treat skin lesions. It is important for medical physicists working with electronic brachytherapy sources to understand the basic physics principles of the sources themselves as well as the variety of applications for which they are being used. The calibration of the sources is different from vendor to vendor and the traceability of calibrations has evolved as new sources came to market. In 2014, a new air‐kerma based standard was introduced by the National Institute of Standards and Technology (NIST) to measure the output of an eBT source. Eventually commercial treatment planning systems should accommodate this new standard and provide NIST traceability to the end user. The calibration and commissioning of an eBT system is unique to its application and typically entails a list of procedural recommendations by the manufacturer. Commissioning measurements are performed using a variety of methods, some of which are modifications of existing AAPM Task Group protocols. A medical physicist should be familiar with the different AAPM Task Group recommendations for applicability to eBT and how to properly adapt them to their needs. In addition to the physical characteristics of an eBT source, the photon energy is substantially lower than from HDR Ir‐192 sources. Consequently, tissue‐specific dosimetry and radiobiological considerations are necessary when comparing these brachytherapy modalities and when making clinical decisions as a radiation therapy team. In this session, the physical characteristics and calibration methodologies of eBt sources will be presented as well as radiobiology considerations and other important clinical considerations.

Learning Objectives:

To understand the basic principles of electronic brachytherapy and the various applications for which it is being used.

To understand the physics of the calibration and commissioning for electronic brachytherapy sources

To understand the unique radiobiology and clinical implementation of electronic brachytherapy systems for skin and IORT techniques

Xoft, Inc. contributed funding toward development of the NIST electronic brachytherapy facility (Michael Mitch).The University of Wisconsin (Wesley Culberson) has received research support funding from Xoft, Inc. Zoubir Ouhib has received partial funding from Elekta Esteya.
MO‐DE‐BRA‐01: Enhancing Radiation Physics Instruction Through Gamification and E‐Learning
Authors: Driewer J , Burchell M , Fowler Z , Lei Y , Morgan B , Zheng D , Zhou S
Published: June 2015

Purpose:

This project sought to “gamify” the instruction of radiation interaction physics concepts for technology students. Gamification applies game mechanics and user interactions in active learning contexts. In one part of this project, a self‐guided eModule was developed for conceptual radiation interaction instruction. In a second part, a web‐based game, Particle Launch (http://particle‐launcher.ist.unomaha.edu), was created to challenge students to quickly apply radiation interaction concepts in a way that is stimulating and motivating.

Methods:

The eModule, focused on conceptual interaction physics, was designed in Adobe Captivate and incorporates animation, web videos, and assessment questions in order to generate student interest. Navigating the whole module takes 40 minutes for beginners. Assessments after three main sections are comprised of 3–4 questions randomly selected from a question pool. In collaboration with the University of Nebraska at Omaha's College of Information Science and Technology, the Particle Launch game was created with the Unity gaming engine and designed with a game‐play look and feel. The object of the game is to utilize different particles, energies, and directions to destroy a target given a limited number of resources and time to complete the task. A rewards system encourages accurate shots.

Results:

The eModule part of the project encourages a flipped classroom model in which class time is devoted to application of concepts rather than information‐based lectures. Currently, eModule assessments are not tracked but this feature could be incorporated to encourage participation. Furthermore, in a class of five technology students, the game was found to be fun and engaging and had the effect of reinforcing basic concepts from the eModule.

Conclusion:

Gamification has significant potential to alter medical physics instruction. Game‐play feedback is an important part of the learning process. Students found Particle Launch inviting and challenging and further research could help game design.

This project was generously supported by the Office of the Vice‐Chancellor for Academic Affairs and the University of Nebraska Medical Center.
MO‐DE‐BRA‐06: MrRSCAL: A Radiological Simulation Tool for Resident Education
Authors: Parker W , Yanasak N
Published: June 2015

Purpose:

The goal of this project was to create a readily accessible, comprehensive‐yet‐flexible interactive MRI simulation tool for use in training and education of radiology residents in particular. This tool was developed to take the place of an MR scanner in laboratory activities, as magnet time has become scarce while hospitals are optimizing clinical scheduling for improved throughput.

Methods:

MrRSCAL (Magnetic resonance Resident Simulation Console for Active Learning) was programmed and coded using Matlab on a Mac workstation utilizing OS X platform. MR‐based brain images were obtained from one of the co‐authors and processed to generate parametric maps. Scanner sounds are also generated via mp3 convolution of a single MR gradient slew with a time‐profile of gradient waveforms.

Results:

MrRSCAL facilitates the simulation of multiple MR sequences with the ability to alter MR parameters via an intuitive GUI control panel. The application allows the user to gain real‐time understanding of image transformation when varying these said parameters by examining the resulting images. Lab procedures can be loaded and displayed for more directed study. The panel is also configurable, providing a simple interface for elementary labs or a full array of controls for the expert user.

Conclusion:

Our introduction of MrRSCAL, which is readily available to users with a current laptop or workstation, allows for individual or group study of MR image acquisition with immediate educational feedback as the MR parameters are manipulated. MrRSCAL can be used at any time and any place once installed, offering a new tool for reviewing relaxometric and artifact principles when studying for boards or investigating properties of a pulse sequence. This tool promises to be extremely useful in conveying traditionally difficult and abstract concepts involved with MR to the radiology resident and other medical professionals at large.
MO‐DE‐210‐03
Authors: Ding K.
Published: June 2015

Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities. It is inexpensive, portable and provides good soft tissue contrast. For challenging soft tissue targets such as pancreatic cancer, ultrasound imaging can be used in combination with pre‐treatment MRI and/or CT to transfer important anatomical features for target localization at time of treatment. The non‐invasive and non‐ionizing nature of ultrasound imaging is particularly powerful for intra‐fraction localization and monitoring. Recognizing these advantages, efforts are being made to incorporate novel robotic approaches to position and manipulate the ultrasound probe during irradiation. These recent enabling developments hold potential to bring ultrasound imaging to a new level of IGRT applications. However, many challenges, not limited to image registration, robotic deployment, probe interference and image acquisition rate, need to be addressed to realize the full potential of IGRT with ultrasound imaging.

Learning Objectives:

Understand the benefits and limitations in using ultrasound to augment MRI and/or CT for motion monitoring during radiation therapy delivery.

Understanding passive and active robotic approaches to implement ultrasound imaging for intra‐fraction monitoring.

Understand issues of probe interference with radiotherapy treatment.

Understand the critical clinical workflow for effective and reproducible IGRT using ultrasound guidance.

The work of X.L. is supported in part by Elekta; J.W. and K.D. is supported in part by a NIH grant R01 CA161613 and by Elekta; D.H. is support in part by a NIH grant R41 CA174089.
MO‐DE‐210‐04: Repositioning and Monitoring of Prostate Cancer Radiotherapy with a New 4D Ultrasound Intra‐Modality IGRT Device
Authors: Fargier‐Voiron M , Guillet L , Pommier P , Sarrut D , Biston M
Published: June 2015

Purpose:

We report our clinical experience using a non‐invasive transperineal (TP) ultrasound (US) probe dedicated to pre‐positioning and monitoring of prostate cancer patients. The accuracy of pre‐treatment positioning was compared to CBCT for prostate and post‐prostatectomy patients. Intrafraction motions were recorded for both localizations. The dosimetric impact of these displacements was finally investigated on prostate patients.

Methods:

Differences between CBCT/CT and TP‐US/TP‐US registrations were analyzed on 427 and 453 sessions for 13 prostate and 14 post‐prostatectomy patients, respectively. Ten prostate patients’ dosimetries were retrospectively planned using 2 different protocols: 80Gy in 40 fractions and 36.25Gy in 5 fractions with a 5mm CTV‐ to‐ PTV margin. The delivery time was measured in order to analyze ranges of intrafraction motions related to each protocol. Mean prostate displacements were calculated for each patient and applied to the treatment isocenter coordinates to evaluate the dosimetric impact of these motions.

Results:

CBCT and TP‐US shifts agreements at ±5mm were 76.6%, 95.1%, 96.3% and 90.3%, 85.0%, 97.6% in anterior‐ posterior, superior‐ inferior and left‐right directions, for prostate and post‐prostatectomy patients, respectively. Intrafraction motions were analyzed considering delivery times of 140 and 290s with an additional time of 120s for patient installation for doses of 2 and 7.25Gy, respectively. Intrafraction motions were patient‐dependent and were larger as the irradiation time increased. Larger displacements were observed for prostate compared to post‐prostatectomy localizations. Shifts above 3mm were observed on 17.6% and 4.5% of the 2Gy sessions against 30.6% and 7.3% of the 7.25Gy sessions in the anterior‐posterior direction for prostate and post‐prostatectomy localizations, respectively. Preliminary dosimetric results showed that intrafraction motions mainly impact the PTV coverage.

Conclusion:

4D TP‐US modality is a promising alternative to irradiating and/or invasive IGRT modalities for both inter and intrafraction motions management. Preliminary dosimetric results show that intrafraction monitoring is mandatory especially for hypofractionated treatments.

M Fargier‐Voiron was supported by a PhD grant from Elekta
MO‐DE‐210‐05: Improved Accuracy of Liver Feature Motion Estimation in B‐Mode Ultrasound for Image‐Guided Radiation Therapy
Authors: O'shea T , Bamber J , Harris E
Published: June 2015

Purpose:

In similarity‐measure based motion estimation incremental tracking (or template update) is challenging due to quantization, bias and accumulation of tracking errors. A method is presented which aims to improve the accuracy of incrementally tracked liver feature motion in long ultrasound sequences.

Methods:

Liver ultrasound data from five healthy volunteers under free breathing were used (15 to 17 Hz imaging rate, 2.9 to 5.5 minutes in length). A normalised cross‐correlation template matching algorithm was implemented to estimate tissue motion. Blood vessel motion was manually annotated for comparison with three tracking code implementations: (i) naive incremental tracking (IT), (ii) IT plus a similarity threshold (ST) template‐update method and (iii) ST coupled with a prediction‐based state observer, known as the alpha‐beta filter (ABST).

Results:

The ABST method produced substantial improvements in vessel tracking accuracy for two‐dimensional vessel motion ranging from 7.9 mm to 40.4 mm (with mean respiratory period: 4.0 ± 1.1 s). The mean and 95% tracking errors were 1.6 mm and 1.4 mm, respectively (compared to 6.2 mm and 9.1 mm, respectively for naive incremental tracking).

Conclusions:

High confidence in the output motion estimation data is required for ultrasound‐based motion estimation for radiation therapy beam tracking and gating. The method presented has potential for monitoring liver vessel translational motion in high frame rate B‐mode data with the required accuracy.

This work is support by Cancer Research UK Programme Grant C33589/A19727.
MO‐DE‐210‐06: Development of a Supercompounded 3D Volumetric Ultrasound Image Guidance System for Prone Accelerated Partial Breast Irradiation (APBI)
Authors: Chiu T , Hrycushko B , Zhao B , Jiang S , Gu X
Published: June 2015

Purpose:

For early‐stage breast cancer, accelerated partial breast irradiation (APBI) is a cost‐effective breast‐conserving treatment. Irradiation in a prone position can mitigate respiratory induced breast movement and achieve maximal sparing of heart and lung tissues. However, accurate dose delivery is challenging due to breast deformation and lumpectomy cavity shrinkage. We propose a 3D volumetric ultrasound (US) image guidance system for accurate prone APBI

Methods:

The designed system, set beneath the prone breast board, consists of a water container, an US scanner, and a two‐layer breast immobilization cup. The outer layer of the breast cup forms the inner wall of water container while the inner layer is attached to patient breast directly to immobilization. The US transducer scans is attached to the outer‐layer of breast cup at the dent of water container. Rotational US scans in a transverse plane are achieved by simultaneously rotating water container and transducer, and multiple transverse scanning forms a 3D scan. A supercompounding‐technique‐based volumetric US reconstruction algorithm is developed for 3D image reconstruction. The performance of the designed system is evaluated with two custom‐made gelatin phantoms containing several cylindrical inserts filled in with water (11% reflection coefficient between materials). One phantom is designed for positioning evaluation while the other is for scaling assessment.

Results:

In the positioning evaluation phantom, the central distances between the inserts are 15, 20, 30 and 40 mm. The distances on reconstructed images differ by −0.19, −0.65, −0.11 and −1.67 mm, respectively. In the scaling evaluation phantom, inserts are 12.7, 19.05, 25.40 and 31.75 mm in diameter. Measured inserts’ sizes on images differed by 0.23, 0.19, −0.1 and 0.22 mm, respectively.

Conclusion:

The phantom evaluation results show that the developed 3D volumetric US system can accurately localize target position and determine target volume, and is a promising image‐guidance tool for prone APBI.
MO‐E‐BRD‐01: Is Non‐Invasive Image‐Guided Breast Brachytherapy Good?
Authors: Hiatt J.
Published: June 2015

Is Non‐invasive Image‐Guided Breast Brachytherapy Good? – Jess Hiatt, MS

Non‐invasive Image‐Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real‐time image‐guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary.

Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? ‐ Dorin Todor, PhD VCU

A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi‐catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues.

to review and understand the evolution and development of APBI using brachytherapy methods

to understand the basis and limitations of radio‐biological ‘equivalence’ between fractionation schedules

to review commonly used and proposed fractionation schedules

Intra‐operative breast brachytherapy: Is one stop shopping best?‐ Bruce Libby, PhD. University of Virginia

A review of intraoperative breast brachytherapy will be presented, including the Targit‐A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed.

Learning Objectives:

To review past and current clinical trials for IORT

To discuss lumpectomy‐scan‐plan‐treat workflow for IORT
MO‐E‐BRD‐02: Accelerated Partial Breast Irradiation in Brachytherapy: Is Shorter Better?
Authors: Todor D.
Published: June 2015

Is Non‐invasive Image‐Guided Breast Brachytherapy Good? – Jess Hiatt, MS

Non‐invasive Image‐Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real‐time image‐guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary.

Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? ‐ Dorin Todor, PhD VCU

A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi‐catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues.

to review and understand the evolution and development of APBI using brachytherapy methods

to understand the basis and limitations of radio‐biological ‘equivalence’ between fractionation schedules

to review commonly used and proposed fractionation schedules

Intra‐operative breast brachytherapy: Is one stop shopping best?‐ Bruce Libby, PhD. University of Virginia

A review of intraoperative breast brachytherapy will be presented, including the Targit‐A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed.

Learning Objectives:

To review past and current clinical trials for IORT

To discuss lumpectomy‐scan‐plan‐treat workflow for IORT
MO‐DE‐210‐07: Investigation of Treatment Interferences of a Novel Robotic Ultrasound Radiotherapy Guidance System with Clinical VMAT Plans for Liver SBRT Patients
Authors: Gong R , Bruder R , Schweikard A , Schlosser J , Hristov D
Published: June 2015

Purpose:

To evaluate the proportion of liver SBRT cases in which robotic ultrasound image guidance concurrent with beam delivery can be deployed without interfering with clinically used VMAT beam configurations.

Methods:

A simulation environment incorporating LINAC, couch, planning CT, and robotic ultrasound guidance hardware was developed. Virtual placement of the robotic ultrasound hardware was guided by a target visibility map rendered on the CT surface. The map was computed on GPU by using the planning CT to simulate ultrasound propagation and attenuation along rays connecting skin surface points to a rasterized imaging target. The visibility map was validated in a prostate phantom experiment by capturing live ultrasound images of the prostate from different phantom locations. In 20 liver SBRT patients treated with VMAT, the simulation environment was used to place the robotic hardware and ultrasound probe at imaging locations indicated on the visibility map. Imaging targets were either entire PTV (range 5.9–679.5 ml) or entire GTV (range 0.9–343.4 ml). Presence or absence of mechanical collisions with LINAC, couch, and patient body as well as interferences with treated beams were recorded.

Results:

For PTV targets, robotic ultrasound guidance without mechanical collision was possible in 80% of the cases and guidance without beam interference was possible in 60% of the cases. For the smaller GTV targets, these proportions were 95% and 85% correspondingly. GTV size (1/20), elongated shape (1/20), and depth (1/20) were the main factors limiting the availability of non‐interfering imaging positions.

Conclusion:

This study indicates that for VMAT liver SBRT, robotic ultrasound tracking of a relevant internal target would be possible in 85% of cases while using treatment plans currently deployed in the clinic. With beam re‐planning in accordance with the presence of robotic ultrasound guidance, intra‐fractional ultrasound guidance may be an option for 95% of the liver SBRT cases.

This project was funded by NIH Grant R41CA174089.
MO‐PIS‐Exhibit Hall‐1: Tools for Collecting and Analyzing Patient Dose Index Information from Imaging Equipment
Authors: Wang J. , Wang J.
Published: June 2015

No Abstract provided
MO‐FG‐BRD‐04: Real‐Time Imaging and Tracking Techniques for Intrafractional Motion Management: MR Tracking
Authors: Low D.
Published: June 2015

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam‐level imaging of radio‐opaque fiducials, fiducial‐less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real‐time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam‐level kilovoltage X‐ray imaging techniques, 2) EPID‐based megavoltage X‐ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI‐based soft‐tissue tracking during radiation delivery.

Learning Objectives:

Understand the fundamentals of real‐time imaging and tracking techniques

Learn about emerging techniques in the field of real‐time tracking

Distinguish between the advantages and disadvantages of different tracking modalities

Understand the role of real‐time tracking techniques within the clinical delivery work‐flow
MO‐FG‐BRB‐03: Addressing the Cancer Challenge: International Cancer Experts Corps
Authors: Coleman N.
Published: June 2015

The global burden of cancer is growing rapidly with an estimated 15 million new cases per year worldwide in 2015, growing to 19 million by 2025 and 24 million by 2035. The largest component of this growth will occur in low‐to‐middle income countries (LMICs). About half of these cases will require radiation treatment. The gap for available cancer treatment, including radiation therapy, between high‐income countries (HICs) and LMICs is enormous. Accurate data and quantitative models to project the needs and the benefits of cancer treatment are a critical first step in closing the large cancer divide between LMICs and HICs. In this context, the Union for International Cancer Control (UICC) has developed a Global Task Force on Radiotherapy for Cancer Control (GTFRCC) with a charge to answer the question as to what it will take to close the gap between what exists today and reasonable access to radiation therapy globally by 2035 and what the potential clinical and economic benefits are for doing this. The Task Force has determined the projections of cancer incidence and the infrastructure required to provide access to radiation therapy globally. Furthermore it has shown that appropriate investment not only yields improved clinical outcomes for millions of patients but that it also provides an overall economic gain throughout all the income settings where this investment is made. This symposium will summarize the facets associated with this global cancer challenge by reviewing the cancer burden, looking at the requirements for radiation therapy, reviewing the benefits of providing such therapy both from a clinical and economic perspective and finally by looking at what approaches can be used to aid in the alleviation of this global cancer challenge. The speakers are world renowned experts in global public health issues (R. Atun), medical physics (D. Jaffray) and radiation oncology (N. Coleman).

Learning Objectives:

To describe the global cancer challenge and the corresponding potential benefits of addressing this challenge.

To describe what radiation therapy infrastructure, in terms of facilities, equipment and personnel, will be required to address this challenge.

To describe models of addressing personnel and infrastructure mobilization and capacity building within regions where significant cancer treatment disparities exist.
MO‐FG‐BRA‐01: Development of An Image‐Guided Dosimetric Planning System for Injectable Brachytherapy Using ELP Nanoparticles
Authors: Lafata K , Schaal J , Liu W , Cai J
Published: June 2015

Purpose:

To develop, validate, and evaluate a methodology for determining dosimetry for intratumoral injections of elastin‐like‐polypeptide (ELP) brachytherapy nanoparticles. These organic‐polymer‐based nanoparticles are injectable, biodegradable, and genetically tunable. We present a genetically encoded polymer‐solution, composed of novel radiolabeled‐ELP nanoparticles that are custom‐designed to self‐assemble into a local source upon intratumoral injection. Our preliminary results of a small animal study demonstrate 100% tumor response, effective radionuclide retention‐rates, strong in vivo stability, and no polymer‐induced toxicities. While our approach is therefore highly promising for improved brachytherapy, the current workflow lacks a dosimetry framework.

Methods:

We are developing a robust software framework that provides image‐guided dosimetric‐planning capabilities for ELP brachytherapy. The user graphically places ELP injection sites within a µCT‐planning‐image, and independently defines each injection volume, concentration, and radioisotope to be used. The resulting internal dosimetry is then pre‐determined by first modeling post‐injection ELP advection‐diffusion, and then calculating the resulting dose distribution based on a point‐ dose‐kernel‐convolution algorithm. We have experimentally measured ELP steady‐state concentrations via µSPECT acquisition, and validated our dose calculation algorithm against Monte Carlo simulations of several radioactivity distributions. Finally, we have investigated potential advantages and limitations of various ELP injection parameters.

Results:

The µSPECT results demonstrated inhomogeneous steady‐state distributions of ELP in tissue, and Monte Carlo radioactivity distributions were designed accordingly. Our algorithm yielded a root‐mean‐square‐error of less than 2% for each distribution tested (average root‐mean‐square‐error was 0.73%). Dose‐Volume‐Histogram analysis of five different plans showed how strategic injection placement, and an injection volume‐tapering technique, could be used to achieve D95% target coverage.

Conclusion:

We have preliminarily developed a novel planning framework for ELP brachytherapy. Its dosimetry accuracy has been validated against Monte Carlo, and we have started to investigate the potential advantages of injection‐based planning. This system, once fully developed, will serve as the technical foundation for our novel approach.