bluuebunny/crossref_metadata_2025_split huggingface dataset:
WE‐EF‐BRA‐01: A Dual‐Use Optical Tomography System for Small Animal Radiation Research Platform (SARRP)
Authors: Wang K , Bin Z , He X , Iordachita I , Wong J 
Published: June 2015

Purpose:We develop a novel dual‐use configuration for a tri‐modality, CBCT/bioluminescence tomography(BLT)/fluorescence tomography(FT), imaging system with the SARRP that can function as a standalone system for longitudinal imaging research and on‐board the SARRP to guide irradiation. BLT provides radiation guidance for soft tissue target, while FT offers functional information allowing mechanistic investigations.Methods:The optical assembly includes CCD camera, lens, filter wheel, 3‐way mirrors, scanning fiber system and light‐tight enclosure. The rotating mirror system directs the optical signal from the animal surface to the camera at multiple projection over 180 degree. The fiber‐laser system serves as the external light source for the FT application. Multiple filters are used for multispectral imaging to enhance localization accuracy using BLT. SARRP CBCT provides anatomical information and geometric mesh for BLT/FT reconstruction. To facilitate dual use, the 3‐way mirror system is cantilevered in front of the camera. The entire optical assembly is driven by a 1D linear stage to dock onto an independent mouse support bed for standalone application. After completion of on‐board optical imaging, the system is retracted from the SARRP to allow irradiation of the mouse.Results:A tissue‐simulating phantom and a mouse model with a luminescence light source are used to demonstrate the function of the dual‐use optical system. Feasibility data have been obtained based on a manual‐docking prototype. The center of mass of light source determined in living mouse with on‐board BLT is within 1±0.2mm of that with CBCT. The performance of the motorized system is expected to be the same and will be presented.Conclusion:We anticipate the motorized dual use system provide significant efficiency gain over our manual docking and off‐line system. By also supporting off‐line longitudinal studies independent of the SARRP, the dual‐use system is a highly efficient and cost‐effective platform to facilitate optical imaging for pre‐clinical radiation research.The work is supported by NIH R01CA158100 and Xstrahl Ltd. Drs. John Wong and Iulian Iordachita receive royalty payment from a licensing agreement between Xstrahl Ltd and Johns Hopkins University. John Wong also has a consultant agreement with Xstrahl Ltd.
WE‐EF‐BRA‐03: Catheter‐ Free Ablation with External Photon Radiation: Treatment Planning, Delivery Considerations, and Correlation of Effects with Delivered Dose
Authors: Deisher A , Anderson S , Cusma J , Herman M , Johnson S , Lehmann H , Packer D , Parker K , Song L , Takami M , Kruse J 
Published: June 2015

Purpose:To plan, target, and calculate delivered dose in atrioventricular node (AVN) ablation with volume‐modulated arc therapy (VMAT) in an intact porcine model.Methods:Seven pigs underwent AVN irradiation, with prescription doses ranging between 25 and 55Gy in a single fraction. Cardiac CT scans were acquired at expiration. Two physicians contoured AVN targets on 10 phases, providing estimates of target motion and inter‐physician variability. Treatment planning was conducted on a static phase‐averaged CT. The volume designated to receive prescription dose covered the full extent of AVN cardiac motion, expanded by 4mm for setup uncertainty. Optimization limited doses to risk structures according to single‐fraction tumor treatment protocols. Orthogonal kV images were used to align bony anatomy at time of treatment. Localization was further refined with respiratory‐gated cone‐beam CT, and range of cardiac motion was verified under fluoroscopy. Beam delivery was respiratory‐gated for expiration with a mean efficiency of 60%. Deformable registration of the 10 cardiac CT phases was used to calculate actual delivered dose for comparison to electro‐anatomical and visually evident lesions.Results:The mean [minimum,maximum] amplitude of AVN cardiac motion was LR 2.9 [1.7,3.9]mm, AP 6.6 [4.4,10.4]mm, and SI 5.6 [2.0,9.9]mm. Incorporating cardiac motion into the dose calculation showed the volume receiving full dose was 40–80% of the volume indicated on the static planning image, although the contoured AVN target received full dose in all animals. Initial results suggest the dimensions of the electro‐anatomical lesion are correlated with the 40Gy isodose volume.Conclusion:Image‐guidance techniques allow for accurate and precise delivery of VMAT for catheter‐free arrhythmia ablation. An arsenal of advanced radiation planning, dose optimization, and image‐guided delivery techniques was employed to assess and mitigate effects of cardiac and respiratory motion. Feasibility of delivery to the pulmonary veins and left ventricular myocardium will be investigated in future studies.D. Packer Disclosures: Abiomed, Biosense Webster, Inc., Boston Scientific Corp., CardioFocus, Inc., Johnson and Johnson, Excerpta Medica, Ortho‐McNeil‐Jannsen, Sanofi Aventis, CardioInsight Technologies, InfoBionic, SIEMENS, Medtronic, Inc., CardioDx, Inc., CardioInsight Technologies, FoxP2 Medica, Mediasphere Medical, Wiley‐Blackwell, St. Jude Medical, Endosense, Thermedical, EP Advocate LLC, Hansen Medical, American Heart Association, EpiEP, NIH
WE‐EF‐303‐03: A New Aperture‐Based Imaging System for Prompt‐Gamma Range Verification of Proton Beam Therapy
Authors: Ready J , Pak R , Mihailescu L , Vetter K 
Published: June 2015

Purpose:To develop and characterize a novel aperture‐based imaging system for high‐energy gamma‐rays. This collimated system will provide 2‐dimensional imaging capability for verification of proton beam range and Bragg peak dose via prompt‐gamma detection.Methods:A multi‐knife‐edge slit collimator has been designed, constructed, and characterized via simulations and experimental measurements. The 20×20×7.5 cm3 tungsten collimator and accompanying LSO scintillation detector were simulated using the TOPAS Geant4 ‐based Monte Carlo package. Iterative reconstruction methods were combined with point response functions to characterize the imaging performance of the system. The response of the system has begun to be characterized experimentally as well, using 2.6 MeV gamma‐rays from Th‐228.Results:Both simulation and experimental results indicate that this collimated system provides 2‐D imaging capability in the energy range of interest for prompt‐gamma dose verification. In the current configuration, with collimator to source distance of 13 cm, image reconstruction of point sources resulted in spatial resolution (FWHM) of approximately 4 mm in both x‐and y‐directions in the imaging plane. The accuracy of positioning the point sources is less than 1 mm.Conclusion:This work has characterized, via simulation and measurements, a novel multi‐knife‐edge slit collimator in front of a more conventional position‐sensitive LSO scintillator detector. The multi‐slit pattern is designed to increase detection efficiency and provide spatial information in 2‐dimensions ‐‐ an improvement over a single‐slit collimator design. The thickness and density of the collimator will allow this detection system to perform well in an environment with high gamma flux, while ultimately providing peak determination accuracy on the order of 1 mm.This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number: DE‐NA0000979 through the Nuclear Science and Security Consortium.
WE‐EF‐303‐05: Development and Commissioning of Real‐Time Imaging Function for Respiratory‐Gated Spot‐Scanning Proton Beam Therapy
Authors: Miyamoto N , Takao S , Matsuura T , Matsuzaki Y , Yamada T , Fujii Y , Matsuo Y , Kidani T , Egashira Y , Umekawa T , Shimizu S , Shirato H , Umegaki K 
Published: June 2015

Purpose:To realize real‐time‐image gated proton beam therapy (RGPT) for treating mobile tumors.Methods:The rotating gantry of spot scanning proton beam therapy has been designed to equip two x‐ray fluoroscopy devices that enable real‐time imaging of the internal fiducial markers during respiration. Three‐dimensional position of the fiducial marker located near the tumor can be calculated from the fluoroscopic images obtained from orthogonal directions and therapeutic beam is gated only when the fiducial marker is within the predefined gating window. Image acquisition rate can be selected from discrete value ranging from 0.1 Hz to 30 Hz. In order to confirm the effectiveness of RGPT and apply it clinically, clinical commissioning was conducted. Commissioning tests were categorized to main three parts including geometric accuracy, temporal accuracy and dosimetric evaluation.Results:Developed real‐time imaging function has been installed and its basic performances have been confirmed. In the evaluation of geometric accuracy, coincidence of three‐dimensional treatment room coordinate system and imaging coordinate system was confirmed to be less than 1 mm. Fiducial markers (gold sphere and coil) were able to be tracked in simulated clinical condition using an anthropomorphic chest phantom. In the evaluation of temporal accuracy, latency from image acquisition to gate on/off signal was about 60 msec in typical case. In dosimetric evaluation, treatment beam characteristics including beam irradiation position and dose output were stable in gated irradiation. Homogeneity indices to the mobile target were 0.99 (static), 0.89 (w/o gating, motion is parallel to direction of scan), 0.75 (w/o gating, perpendicular), 0.98 (w/ gating, parallel) and 0.93 (w/ gating, perpendicular). Dose homogeneity to the mobile target can be maintained in RGPT.Conclusion:Real‐time imaging function utilizing x‐ray fluoroscopy has been developed and commissioned successfully in order to realize RGPT.Funding Support: This research was partially supported by Japan Society for the Promotion of Science (JSPS) through the FIRST Program. Conflict of Interest: Prof. Shirato has research fund from Hitachi Ltd, Mitsubishi Heavy Industries Ltd and Shimadzu Corporation.
WE‐EF‐204‐01: Pre‐Clinical Imaging for Co‐Clinical Trials
Authors: Hazle J. 
Published: June 2015

As molecular biology breakthroughs in understanding cancers and other diseases, hundreds of new drugs wait testing. In the last decade, mouse models have been evolved to better mimic human diseases genetically and biologically. These reliable mouse models allow us to determine which genetic elements, pathways and mutations impact on therapy. The co‐clinical trial strategy is to conduct a human clinical trial for a therapeutic drug and test it in mouse models at the same time. This strategy has the potential to accelerate the drug testing process and identify the patient population that will respond to the drug. Imaging plays an important role in co‐clinical trials. In this symposium, four speakers will discuss advancements and issues in pre‐clinical imaging, murine models, imaging hardware and software, and funding opportunities in co‐clinical trials.Learning Objectives:

Multi‐modality pre‐clinical imaging hardware and software, and new technologies (e.g., hyperpolarized MRI)
Selection of animal models from physiological and genetic perspectives with examples in colon, pancreatic and lung cancers
NCI funding opportunities
WE‐EF‐204‐02: Murine Model Systems for Co‐Clinical Trials
Authors: Manning H. 
Published: June 2015

As molecular biology breakthroughs in understanding cancers and other diseases, hundreds of new drugs wait testing. In the last decade, mouse models have been evolved to better mimic human diseases genetically and biologically. These reliable mouse models allow us to determine which genetic elements, pathways and mutations impact on therapy. The co‐clinical trial strategy is to conduct a human clinical trial for a therapeutic drug and test it in mouse models at the same time. This strategy has the potential to accelerate the drug testing process and identify the patient population that will respond to the drug. Imaging plays an important role in co‐clinical trials. In this symposium, four speakers will discuss advancements and issues in pre‐clinical imaging, murine models, imaging hardware and software, and funding opportunities in co‐clinical trials.Learning Objectives:

Multi‐modality pre‐clinical imaging hardware and software, and new technologies (e.g., hyperpolarized MRI)
Selection of animal models from physiological and genetic perspectives with examples in colon, pancreatic and lung cancers
NCI funding opportunities
WE‐EF‐207‐05: Monte Carlo Dosimetry for a Dedicated Cone‐Beam CT Head Scanner
Authors: Sisniega A , Zbijewski W , Xu J , Dang H , Stayman J W , Aygun N , Koliatsos V E , Wang X , Foos D H , Siewerdsen J H 
Published: June 2015

Purpose:Cone‐Beam CT (CBCT) is an attractive platform for point‐of‐care imaging of traumatic brain injury and intracranial hemorrhage. This work implements and evaluates a fast Monte‐Carlo (MC) dose estimation engine for development of a dedicated head CBCT scanner, optimization of acquisition protocols, geometry, bowtie filter designs, and patient‐specific dosimetry.Methods:Dose scoring with a GPU‐based MC CBCT simulator was validated on an imaging bench using a modified 16 cm CTDI phantom with 7 ion chamber shafts along the central ray for 80–100 kVp (+2 mm Al, +0.2 mm Cu). Dose distributions were computed in a segmented CBCT reconstruction of an anthropomorphic head phantom with 4×10⁵ tracked photons per scan (5 min runtime). Circular orbits with angular span ranging from short scan (180° + fan angle) to full rotation (360°) were considered for fixed total mAs per scan. Two aluminum filters were investigated: aggressive bowtie, and moderate bowtie (matched to 16 cm and 32 cm water cylinder, respectively).Results:MC dose estimates showed strong agreement with measurements (RMSE<0.001 mGy/mAs). A moderate (aggressive) bowtie reduced the dose, per total mAs, by 20% (30%) at the center of the head, by 40% (50%) at the eye lens, and by 70% (80%) at the posterior skin entrance. For the no bowtie configuration, a short scan reduced the eye lens dose by 62% (from 0.08 mGy/mAs to 0.03 mGy/mAs) compared to full scan, although the dose to spinal bone marrow increased by 40%. For both bowties, the short scan resulted in a similar 40% increase in bone marrow dose, but the reduction in the eye lens was more pronounced: 70% (90%) for the moderate (aggressive) bowtie.Conclusions:Dose maps obtained with validated MC simulation demonstrated dose reduction in sensitive structures (eye lens and bone marrow) through combination of short‐scan trajectories and bowtie filters.Xiaohui Wang and David Foos are employees of Carestream Health
WE‐EF‐210‐03: Ultrasound‐Mediated Stimulation of Nanoparticles for Therapeutic Applications
Authors: Porter T. 
Published: June 2015

Recent advances in ultrasound‐related technologies have had a significant impact on enhancing image quality as well as offering new approaches for quantitative ultrasonic imaging and therapeutic applications. The presentations associated with this session will provide an overview of advances in ultrasound image formation, the development of using nanoparticles for therapeutic ultrasound applications, as well as approaches for assessing the intrinsic viscoelastic properties of tissue and methods for monitoring tissue response to therapy.Learning Objectives:

Develop a general understanding of new technologies associated with enhanced ultrasound image formation and volume imaging.
Develop an understanding of new ultrasound‐based technologies for quantitative assessment of intrinsic tissue properties.
Develop an understanding of novel approaches for ultrasound‐mediated non‐invasive therapeutic applications.
Dr. Rao is an employee of Siemens Ultrasound
WE‐E‐201‐03: Uncertainty and Issues in Biological Modeling for the Modern Medical Physicist
Authors: Altman M. 
Published: June 2015

Physicists are often expected to have a solid grounding in experimental design and statistical analysis, sometimes filling in when biostatisticians or other experts are not available for consultation. Unfortunately, graduate education on these topics is seldom emphasized and few opportunities for continuing education exist. Clinical physicists incorporate new technology and methods into their practice based on published literature. A poor understanding of experimental design and analysis could Result in inappropriate use of new techniques. Clinical physicists also improve current practice through quality initiatives that require sound experimental design and analysis. Academic physicists with a poor understanding of design and analysis may produce ambiguous (or misleading) results. This can Result in unnecessary rewrites, publication rejection, and experimental redesign (wasting time, money, and effort).This symposium will provide a practical review of error and uncertainty, common study designs, and statistical tests. Instruction will primarily focus on practical implementation through examples and answer questions such as: where would you typically apply the test/design and where is the test/design typically misapplied (i.e., common pitfalls)? An analysis of error and uncertainty will also be explored using biological studies and associated modeling as a specific use case.Learning Objectives:

Understand common experimental testing and clinical trial designs, what questions they can answer, and how to interpret the results
Determine where specific statistical tests are appropriate and identify common pitfalls
Understand the how uncertainty and error are addressed in biological testing and associated biological modeling.
WE‐EF‐210‐02: Ultrasound Innovations in Therapy Response Monitoring
Authors: Czarnota G. 
Published: June 2015

Recent advances in ultrasound‐related technologies have had a significant impact on enhancing image quality as well as offering new approaches for quantitative ultrasonic imaging and therapeutic applications. The presentations associated with this session will provide an overview of advances in ultrasound image formation, the development of using nanoparticles for therapeutic ultrasound applications, as well as approaches for assessing the intrinsic viscoelastic properties of tissue and methods for monitoring tissue response to therapy.Learning Objectives:

Develop a general understanding of new technologies associated with enhanced ultrasound image formation and volume imaging.
Develop an understanding of new ultrasound‐based technologies for quantitative assessment of intrinsic tissue properties.
Develop an understanding of novel approaches for ultrasound‐mediated non‐invasive therapeutic applications.
Dr. Rao is an employee of Siemens Ultrasound
WE‐F‐201‐03: Evaluate Clinical Cases Using Commercially Available Systems and Compare to TG‐43 Dosimetry
Authors: Beaulieu L. 
Published: June 2015

With the recent introduction of heterogeneity correction algorithms for brachytherapy, the AAPM community is still unclear on how to commission and implement these into clinical practice. The recently‐published AAPM TG‐186 report discusses important issues for clinical implementation of these algorithms. A charge of the AAPM‐ESTRO‐ABG Working Group on MBDCA in Brachytherapy (WGMBDCA) is the development of a set of well‐defined test case plans, available as references in the software commissioning process to be performed by clinical end‐users. In this practical medical physics course, specific examples on how to perform the commissioning process are presented, as well as descriptions of the clinical impact from recent literature reporting comparisons of TG‐43 and heterogeneity‐based dosimetry.Learning Objectives:

Identify key clinical applications needing advanced dose calculation in brachytherapy.
Review TG‐186 and WGMBDCA guidelines, commission process, and dosimetry benchmarks.
Evaluate clinical cases using commercially available systems and compare to TG‐43 dosimetry
WE‐G‐304‐02: Legal Aspects of Employment
Authors: Masten J. 
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‐08: Motion Analysis for Rectal Cancer: Implications for Adaptive Radiotherapy On the MR‐Linac
Authors: Kleijnen J , van Asselen B , Burbach M , Intven M , Philippens M , Reerink O , Lagendijk J , Raaymakers B 
Published: June 2015

Purpose:Purpose of this study is to find the optimal trade‐off between adaptation interval and margin reduction and to define the implications of motion for rectal cancer boost radiotherapy on a MR‐linac.Methods:Daily MRI scans were acquired of 16 patients, diagnosed with rectal cancer, prior to each radiotherapy fraction in one week (N=76). Each scan session consisted of T2‐weighted and three 2D sagittal cine‐MRI, at begin (t=0 min), middle (t=9:30 min) and end (t=18:00 min) of scan session, for 1 minute at 2 Hz temporal resolution. Tumor and clinical target volume (CTV) were delineated on each T2‐weighted scan and transferred to each cine‐MRI. The start frame of the begin scan was used as reference and registered to frames at time‐points 15, 30 and 60 seconds, 9:30 and 18:00 minutes and 1, 2, 3 and 4 days later. Per time‐point, motion of delineated voxels was evaluated using the deformation vector fields of the registrations and the 95th percentile distance (dist95%) was calculated as measure of motion. Per time‐point, the distance that includes 90% of all cases was taken as estimate of required planning target volume (PTV)‐margin.Results:Highest motion reduction is observed going from 9:30 minutes to 60 seconds. We observe a reduction in margin estimates from 10.6 to 2.7 mm and 16.1 to 4.6 mm for tumor and CTV, respectively, when adapting every 60 seconds compared to not adapting treatment. A 75% and 71% reduction, respectively. Further reduction in adaptation time‐interval yields only marginal motion reduction. For adaptation intervals longer than 18:00 minutes only small motion reductions are observed.Conclusion:The optimal adaptation interval for adaptive rectal cancer (boost) treatments on a MR‐linac is 60 seconds. This results in substantial smaller PTV‐margin estimates. Adaptation intervals of 18:00 minutes and higher, show little improvement in motion reduction.