bluuebunny/crossref_metadata_2025_split huggingface dataset:
SU‐D‐201‐06: Remote Dosmetric Auditing of VMAT Deliveries for Clinical Trials Using EPID
Authors: Legge K , Lehmann J , Vial P , Miri N , Greer P 
Published: July 2016

Purpose:To develop a method for remote dosimetric auditing the delivery of VMAT using EPID which allows for simple, inexpensive and time efficient dosimetric credentialing for clinical trials.Methods:Remote centers are provided with CT datasets and planning guidelines to produce VMAT plans for a head and neck and a post‐prostatectomy treatment. Plans are transferred in the planning system to two virtual water equivalent phantoms, one flat and one cylindrical. Cine images are acquired during VMAT delivery to the EPID in air with gantry angle recorded in image headers. Centers also deliver provided calibration plans to enable EPID signal to dose conversion, determination of the central axis, and correction of EPID sag prior to analysis. EPID images and planned doses are sent to the central site. EPID cine images are converted to dose in the virtual phantoms using an established backprojection method (King et al., Med.Phys. 2012) with EPID backscatter correction. Individual arcs (with gantry angles collapsed to zero) are evaluated at 10 cm depth in the flat phantom using 2D gamma, and total doses are evaluated in the cylindrical phantom using 3D gamma. Results are reported for criteria of 3%,3mm, 3%,2mm and 2%,2mm for all points greater than 10% of global maximum.Results:The pilot study for Varian centers has commenced, and three centers have been audited for head and neck plans and two for post‐prostatectomy plans to date. The mean pass rate for arc‐by‐arc 2D analysis at 3%,3mm is 99.5% and for 3D analysis is 95.8%. A method for Elekta linacs using an inclinometer for gantry angle information is under development.Conclusion:Preliminary results for this new method are promising. The method takes advantage of EPID equipment available at most centers and clinically established software to provide a feasible, low cost solution to credentialing centers for clinical trials.Funding has been provided from Calvary Mater Newcastle Department of Radiation Oncology, TROG Cancer Research and the University of Newcastle. Kimberley Legge is the recipient of an Australian Postgraduate Award. Narges Miri is a recipient of a University of Newcastle postgraduate scholarship.
SU‐D‐BRC‐04: Development of Proton Tissue Equivalent Materials for Calibration and Dosimetry Studies
Authors: Olguin E , Flampouri S , Lipnharski I , Bolch W 
Published: July 2016

Purpose:To develop new proton tissue equivalent materials (PTEM), urethane and fiberglass based, for proton therapy calibration and dosimetry studies. Existing tissue equivalent plastics are applicable only for x‐rays because they focus on matching mass attenuation coefficients. This study aims to create new plastics that match mass stopping powers for proton therapy applications instead.Methods:New PTEMs were constructed using urethane and fiberglass resin materials for soft, fat, bone, and lung tissue. The stoichiometric analysis method was first used to determine the elemental composition of each unknown constituent. New initial formulae were then developed for each of the 4 PTEMs using the new elemental compositions and various additives. Samples of each plastic were then created and exposed to a well defined proton beam at the UF Health Proton Therapy Institute (UFHPTI) to validate its mass stopping power.Results:The stoichiometric analysis method revealed the elemental composition of the 3 components used in creating the PTEMs. These urethane and fiberglass based resins were combined with additives such as calcium carbonate, aluminum hydroxide, and phenolic micro spheres to achieve the desired mass stopping powers and densities. Validation at the UFHPTI revealed adjustments had to be made to the formulae, but the plastics eventually had the desired properties after a few iterations. The mass stopping power, density, and Hounsfield Unit of each of the 4 PTEMs were within acceptable tolerances.Conclusion:Four proton tissue equivalent plastics were developed: soft, fat, bone, and lung tissue. These plastics match each of the corresponding tissue's mass stopping power, density, and Hounsfield Unit, meaning they are truly tissue equivalent for proton therapy applications. They can now be used to calibrate proton therapy treatment planning systems, improve range uncertainties, validate proton therapy Monte Carlo simulations, and assess in‐field and out‐of‐field organ doses.
SU‐D‐BRC‐05: Effects of Motion and Variable RBE in a Lung Patient Treated with Passively Scattered Protons
Authors: Mirkovic D , Titt U , Yepes P , Mohan R 
Published: July 2016

Purpose:To evaluate effects of motion and variable relative biological effectiveness (RBE) in a lung cancer patient treated with passively scattered proton therapy using dose volume histograms associated with patient dose computed using three different methods.Methods:A proton treatment plan of a lung cancer patient optimized using clinical treatment planning system (TPS) was used to construct a detailed Monte Carlo (MC) model of the beam delivery system and the patient specific aperture and compensator. A phase space file containing all particles transported through the beam line was collected at the distal surface of the range compensator and subsequently transported through two different patient models. The first model was based on the average CT used by the TPS and the second model included all 10 phases of the corresponding 4DCT. The physical dose and proton linear energy transfer (LET) were computed in each voxel of two models and used to compute constant and variable RBE MC dose on average CT and 4D CT. The MC computed doses were compared to the TPS dose using dose volume histograms for relevant structures.Results:The results show significant differences in doses to the target and critical structures suggesting the need for more accurate proton dose computation methods. In particular, the 4D dose shows reduced coverage of the target and higher dose to the spinal cord, while variable RBE dose shows higher lung dose.Conclusion:The methodology developed in this pilot study is currently used for the analysis of a cohort of ∼90 lung patients from a clinical trial comparing proton and photon therapy for lung cancer. The results from this study will help us in determining the clinical significance of more accurate dose computation models in proton therapy.
SU‐D‐BRC‐07: System Design for a 3D Volumetric Scintillation Detector Using SCMOS Cameras
Authors: Darne C , Robertson D , Alsanea F , Beddar S 
Published: July 2016

Purpose:The purpose of this project is to build a volumetric scintillation detector for quantitative imaging of 3D dose distributions of proton beams accurately in near real‐time.Methods:The liquid scintillator (LS) detector consists of a transparent acrylic tank (20×20×20 cm3) filled with a liquid scintillator that when irradiated with protons generates scintillation light. To track rapid spatial and dose variations in spot scanning proton beams we used three scientific‐complementary metal‐oxide semiconductor (sCMOS) imagers (2560×2160 pixels). The cameras collect optical signal from three orthogonal projections. To reduce system footprint two mirrors oriented at 45° to the tank surfaces redirect scintillation light to cameras for capturing top and right views. Selection of fixed focal length objective lenses for these cameras was based on their ability to provide large depth of field (DoF) and required field of view (FoV). Multiple cross‐hairs imprinted on the tank surfaces allow for image corrections arising from camera perspective and refraction.Results:We determined that by setting sCMOS to 16‐bit dynamic range, truncating its FoV (1100×1100 pixels) to image the entire volume of the LS detector, and using 5.6 msec integration time imaging rate can be ramped up to 88 frames per second (fps). 20 mm focal length lens provides a 20 cm imaging DoF and 0.24 mm/pixel resolution. Master‐slave camera configuration enable the slaves to initiate image acquisition instantly (within 2 µsec) after receiving a trigger signal. A computer with 128 GB RAM was used for spooling images from the cameras and can sustain a maximum recording time of 2 min per camera at 75 fps.Conclusion:The three sCMOS cameras are capable of high speed imaging. They can therefore be used for quick, high‐resolution, and precise mapping of dose distributions from scanned spot proton beams in three dimensions.
SU‐F‐E‐04: A Paris System‐Based Implant Approach to Hyperthermia Cancer Tumor with Gold Seeds and Ultrasound
Authors: Austerlitz C , Barros A , Gkigkitzis I , Haranas I , Zhu D , Campos D 
Published: July 2016

Purpose:To apply the Paris system‐based implant for an uniform bio‐heat distribution from implanted gold rods in tissue insonated with ultrasound.Methods:Experiments with single‐plane implants using parallel equidistant 1.018 ± 0.015 cm height and 0.136 ± 0.001 cm diameter 24‐K gold rods) arranged in triangular and square shapes were performed in Mus Musculus white mice (medial dorsal region). The mice were anesthetized and gold rods were implanted by means of a trocar needle and the implanted region was insonated with a 4‐cm diameter transducer oscillating with a nominal frequency of 1 MHz and power of about 75 W. Intramuscular tissue temperature measurements were taken using implantable needle type thermocouples affixed to a portable Fluke thermometer. Superficial tissue temperature profile was also measured with a FLIR infrared camera and thermographic analysis were performed using the ImageJ computer software. In both cases, the central implant planes have been assigned to that approximately bisects all the implanted rods.Results:Measured with the needle type thermistor, for the triangular implant, the percentage deviation between the maximum and minimum temperature within the triangular plane was 5%. For a square shape, this percentage deviation was 6%. The thermographic analysis have shown a deviation of 3% and 5% for the triangular and square shapes, respectively.Conclusion:Based on the temperature measurements with needle type thermistor and thermographic analysis, the Paris system‐based implant approach for gold rods implanted in tissue and exposed to ultrasound may greatly improve the bio‐heat propagation and sustain a constant temperature profile inside triangular and square patterns formed by gold rods implants. Additionally, the Paris system may minimize ablations areas and treatment length in hyperthermia if used in cancer tumor treatment.
SU‐F‐E‐06: Dosimetric Characterization of Small Photons Beams of a Novel Linear Accelerator
Authors: Almonte A , Polanco G , Sanchez E 
Published: July 2016

Purpose:The aim of the present contribution was to measure the main dosimetric quantities of small fields produced by UNIQUE and evaluate its matching with the corresponding dosimetric data of one 21EX conventional linear accelerator (Varian) in operation at the same center. The second step was to evaluate comparative performance of the EDGE diode detector and the PinPoint micro‐ionization chamber for dosimetry of small fields.Methods:UNIQUE is configured with MLC (120 leaves with 0.5 cm leaf width) and a single low photon energy of 6 MV. Beam data were measured with scanning EDGE diode detector (volume of 0.019 mm3), a PinPoint micro‐ionization chamber (PTW) and for larger fields (≥ 4×4cm2) a PTW Semi flex chamber (0.125 cm3) was used. The scanning system used was the 3D cylindrical tank manufactured by Sun Nuclear, Inc. The measurement of PDD and profiles were done at 100 cm SSD and 1.5 depth; the relative output factors were measured at 10 cm depth.Results:PDD and the profile data showed less than 1% variation between the two linear accelerators for fields size between 2×2 cm2 and 5×5cm2. Output factor differences was less than 1% for field sizes between 3×3 cm2 and 10×10 cm2 and less of 1.5 % for fields of 1.5×1.5 cm2 and 2×2 cm2 respectively. The dmax value of the EDGE diode detector, measured from the PDD, was 8.347 mm for 0.5×0,5cm2 for UNIQUE. The performance of EDGE diode detector was comparable for all measurements in small fields.Conclusion:UNIQUE linear accelerator show similar dosimetrics characteristics as conventional 21EX Varian linear accelerator for small, medium and large field sizes.EDGE detector show good performance by measuring dosimetrics quantities in small fields typically used in IMRT and radiosurgery treatments.
SU‐F‐E‐12: Elective International Rotations in Medical Physics Residency Programs
Authors: Brown D , Mundt A , Einck J , Pawlicki T 
Published: July 2016

Purpose:The purpose of this educational program is to motivate talented, intelligent individuals to become stakeholders in the global effort to improve access to radiotherapy.Methods:The need to improve global access to radiotherapy has been clearly established and several organizations are making substantial progress in securing funding and developing plans to achieve this worthwhile goal. The incorporation of elective international rotations in residency programs may provide one possible mechanism to promote and support this future investment. We recently incorporated an elective 1‐month international rotation into our CAMPEP accredited Medical Physics residency program, with our first rotation taking place in Vietnam. A unique aspect of this rotation was that it was scheduled collaboratively with our Radiation Oncology residency program such that Radiation Oncology and Medical Physics residents traveled to the same clinic at the same time.Results:We believe the international rotation substantially enhances the educational experience, providing additional benefits to residents by increasing cross‐disciplinary learning and offering a shared learning experience. The combined international rotation may also increase benefit to the host institution by modeling positive multidisciplinary working relationships between Radiation Oncologists and Medical Physicists. Our first resident returned with several ideas designed to improve radiotherapy in resource‐limited settings – one of which is currently being pursued in collaboration with a vendor.Conclusion:The elective international rotation provides a unique learning experience that has the potential to motivate residents to become stakeholders in the global effort to improve access to radiotherapy. What better way to prepare the next generation of Medical Physicists to meet the challenges of improving global access to radiotherapy than to provide them with training experiences that motivate them to be socially conscious and equip them with the clinical and problem solving skills required to deliver effective treatments in resource limited settings?
SU‐F‐E‐14: Global Radiation Oncology Education and Training in Medical Physics Powered by Information and Communication Technologies
Authors: Ngwa W , Sajo E , Ngoma T , Dachi J , Julius Mwaiselage J , Kenton O , Avery S 
Published: July 2016

Purpose:Recent publications have highlighted the potential of Information and Communication Technologies (ICTs) to catalyze collaborations in cancer care, research and education in global radiation oncology. This work reports on the use of ICTs for global Medical Physics education and training across three countries: USA, Tanzania and KuwaitMethods:An online education platform was established by Radiation Oncology Faculty from Harvard Medical School, and the University of Pennsylvania with integrated Medical Physics Course modules accessible to trainees in Tanzania via partnership with the Muhimbili University of Health and Allied Sciences, and the Ocean Road Cancer Institute. The course modules incorporated lectures covering Radiation Therapy Physics with videos, discussion board, assessments and grade center. Faculty at Harvard Medical School and the University of Massachusetts Lowell also employed weekly Skype meetings to train/mentor three graduate students, living out‐of‐state and in Kuwait for up to 9 research credits per semester for over two semesters towards obtaining their graduate degreesResults:Students were able to successfully access the Medical Physics course modules and participate in learning activities, online discussion boards, and assessments. Other instructors could also access/co‐teach the course modules from USA and Tanzania. Meanwhile all three graduate students with remote training via Skype and email made major progress in their graduate training with each one of them submitting their research results as abstracts to be presented at the 2016 AAPM conference. One student has also published her work already and all three are developing these abstracts for publication in peer‐reviewed journals.Conclusion:Altogether, this work highlights concrete examples/model on how ICTs can be used for capacity building in Medical Physics across continents, for both education and research training needed for Masters/PhD degrees. The developed modules and model will be scaled to benefit many more trainees and other developing countries.
SU‐F‐P‐01: Changing Your Oncology Information System: A Detailed Process and Lessons Learned
Authors: Abing C 
Published: July 2016

Purpose:Radiation Oncology departments are faced with many options for pairing their treatment machines with record and verify systems. Recently, there is a push to have a single‐vendor‐solution. In order to achieve this, the department must go through an intense and rigorous transition process. Our department has recently completed this process and now offer a detailed description of the process along with lessons learned.Methods:Our cancer center transitioned from a multi‐vendor department to a single‐vendor department over the 2015 calendar year. Our staff was partitioned off into superuser groups, an interface team, migration team, and go‐live team. Six months after successful implementation, a detailed survey was sent to the radiation oncology department to determine areas for improvement as well as successes in the process.Results:The transition between record and verify systems was considered a complete success. The results of the survey did point out some areas for improving inefficiencies with our staff; both interactions between each other and the vendors.Conclusion:Though this process was intricate and lengthy, it can be made easier with careful planning and detailed designation of project responsibilities. Our survey results and retrospective analysis of the transition are valuable to those wishing to make this change.
SU‐F‐P‐02: A New Framework for the Equipment Donation Program
Authors: Brown D , Court L , Hudson A , Odom A , Pipman Y 
Published: July 2016

Purpose:The Equipment Donation Sub‐Committee has developed a new, formalized process for both donating and requesting donated equipment. The purpose of the framework is to increase the likelihood that available, working‐order equipment is put to good use at functional, deserving clinics.Methods:A consensus approach was used to develop a fresh approach to equipment donation and requesting equipment for donation. The committee developed specific forms for people who wish to donate equipment and for those who are seeking specific donated equipment. The forms include a summary of the equipment as well as questions designed to inform the committee with respect to the condition of the equipment, the resources of the clinic that is requesting equipment, the specific need for requested equipment, whether or not additional components or software are required for its proper functioning, and ancillary considerations such as regulatory and import rules that may affect the donation. Following submission of the forms the equipment, or request, are entered into a database, reviewed by the committee, and compatibility matches are proposed.Results:This is the first time a formalized, consensus‐based approach has been used by the Equipment Donation Sub‐Committee. Forms are available on the aapm.org website and should be emailed to equipment.donation@aapm.org. The first applications using this new process will be summarized and discussed.Conclusion:We anticipate this process will facilitate and expedite the process of equipment donation and will serve as a tool for assessing and improving the program.
SU‐F‐P‐03: Management of Time to Treatment Inititation: Case for An Electronic Whiteboard
Authors: Adnani N 
Published: July 2016

Purpose:To determine if data mining of an electronic whiteboard improves the management of the Time to Treatment Initiation (TTI) in radiation oncology.Methods:An electronic whiteboard designed to help in managing the planning workflow and improves communication regarding patient planning progress was used to record the dates at which each phase of the planning process began or completed. These are CT Sim date, Plan Start, Physician Review, Physicist Review, Approval for Treatment Delivery, Setup or Verification of Simulation.Results:During clinical implementation, the electronic whiteboard was able to fulfill its primary objective of providing a transparent account of the planning progress of each patient. Peer pressure also meant that individual tasks, such as contouring, were easily brought to the attention of the responsible party and prioritized accordingly. Data mining to analyze the electronic whiteboard per patient (figure 1), per diagnosis (figure 2), per treatment modality (figure 3), per physician (figure 4), per planner (figure 5), etc., added another sophisticated tool in the management of Time to Treatment Initiation without compromising quality of the plans being generated. A longer than necessary time between CT Sim and Plan Start can be discussed among the members of the treatment team as an indication of inadequate/outdated CT Simulator, Contouring Tools, Image Fusion Tools, Other Imaging Studies (MRI, PET/CT) performed, etc. The same for the Plan Start to Physician Review where an extended time than expected may be due unrealistic planning goals, limited planning system features, etc.Conclusion:An Electronic Whiteboard in radiation oncology is not only helping with organizing planning workflow, it is also a potent tool that can be used to reduce the Time to Treatment Initiation by providing the clinic with hard data about the duration of each phase treatment planning as a function of different variable affecting the planning process.The work is supported by the Global Medical Physics Institute.