bluuebunny/crossref_metadata_2025_split huggingface dataset:
WE‐A‐BRC‐01: IMRT in Gynecological Malignancies
Authors: Aydogan B 
Published: April 2010

Intensity modulated radiation therapy (IMRT) is increasingly used for the treatment of gynecological tumors. Successful implementation requires careful attention to every detail from patient selection to simulation, to planning, to setup, to localization, and to delivery. At the University of Chicago, all patients are simulated and treated in supine position using customized alpha cradles indexed to the treatment table. Oral, IV and rectal contrast are used to help in the delineation of the CTV and surrounding normal tissues. The CTV consists of the upper half of the vagina, uterus (if present), parametrial tissues, parasacral region, and the contrast enhanced vessels plus a 2cm margin to identify the common, external and internal nodal regions. PTV is constructed by adding a margin based on the setup uncertainty and organ motion data. Normal tissues contoured include bladder, rectum, small bowel and pelvic bone marrow. For treatment planning, 9 equally spaced co‐planar beams are used. Input parameters derived for the PTV and surrounding normal tissues were developed over the time, and their evolution will be discussed. Treatment plans are evaluated primarily based on the PTV coverage and normal tissue DVHs. 3‐D dose distribution plays an important role in the IMRT delivery and is rigorously evaluated by both physicists and physicians at our institutions. Acceptable plans are the ones that have a minimum coverage of 98% of the PTV volume with the prescription dose while no more than 2% of the PTV receives more than 110% of the prescription dose. Evaluation of small bowel dose is based on a NTCP analysis for the incidence of acute gastrointestinal toxicity of IMRT patients treated in our center. From this analysis, small bowel volume receiving prescription dose (45Gy) should be less than 200cc. Plan acceptance criteria for rectum and bladder will also be discussed during this course. Recent studies conducted in our center studies have associated the volume of pelvic and lumbosacral bone marrow (PBM and LSBM) receiving 10 and 20 Gy with acute hematologic toxicity (AHT) in patients receiving concurrent chemotherapy and IMRT. We will discuss and present plan consideration for bone marrow sparing IMRT to reduce AHT in these patients. QA is one of the most important and integral part of any radiation therapy procedure. IMRT QA, in our institution, is performed using independent monitor unit verification (MUV) and patient specific measurements and will be discussed in details. In addition, recent studies reporting adaptive treatment and image guided approaches in the treatment of gynecological tumors will be briefly reviewed.Learning Objectives:1. To understand the practical and fundamental aspects of IMRT planning for gynecological malignancies2. To discuss the GYN‐IMRT plan evaluation and acceptance criteria3. To review and discuss the IMRT quality assurance issues for this disease site.4. To briefly review and critique adaptive and image guided GYN‐IMRT approaches.
WE‐A‐213A‐01: Ultrasound Beamformation and Image Reconstruction
Authors: Moore W 
Published: April 2010

Modern technologically intensive diagnostic ultrasound systems are utilizing numerous new and powerful beamformation and image construction processes integrated into the design of the transmit, receive and processing chain of the system. These new processes, how the imaging and Doppler data is captured, processed and displayed need to be well understood by both medical physicists and clinicians to ensure proper testing and performance evaluation of the ultrasound device, as well as their attendant transducers (probes), and to ensure the safety and clinical efficacy of the ultrasound study. This presentation will focus on these new processes and advanced imaging technologies, how they can be tested and evaluated for effectiveness and what new imaging and display formats we will likely see in the next 2 to 3 years.Learning Objectives:1. Understand modern beamforming techniques2. Understand ultrasound image processing3. Understand modern image reconstruction techniques
WE‐B‐211A‐01: Strengths and Limitations of Anatomical and Spectroscopic MRI in Radiation Oncology Treatment Planning
Authors: Bayouth J 
Published: April 2010

Magnetic resonance imaging (MRI) is playing an increasingly important role in radiation oncology treatment planning. As compared to computed tomography (CT), MRI provides excellent soft tissue contrast making it ideal for imaging brain tumors. Other anatomical sites (e.g., prostate, pelvis, head and neck, extremities, abdomen, etc.) also benefit from the soft tissue contrast provided by MRI, but are limited by difficulties in reproducing CT patient positioning in the MRI as well as geometric distortions introduced within the MRI datasets. These issues will be described, along with techniques for their minimization and quantification. MRI is also a powerful and non‐invasive imaging modality to assess tissue motion, caused by a host of physiological processes (respiration, peristalsis, bladder and/or rectal filling, etc.). Clinical approaches to using MRI for motion management will be described.In addition to morphological imaging, magnetic resonance spectroscopic imaging (MRSI) provides a non‐invasive spatial mapping of abnormal tumor metabolism. This information may provide critically relevant assessment of the presence and extent of tumor activity, which may be substantially different from those considered to contain tumor based on T1 and T2 imaging. Many uncertainties remain: geometric and quantification accuracy of the acquired MRSI data due to magnetic field imperfections, lack of adequate anatomical details with MRSI images for registration with planning CT, and lacking essential DICOM objects hamper the incorporation of MRSI information into the treatment planning process. Clinical approaches to using MRSI for tumor target delineation will also be described.This lecture will outline the indications for MRI in radiation oncology treatment planning for both external beam and brachytherapy. Examples are provided for many anatomical sites, along registration of MRI datasets with PET/CT. Approaches that can be used to validate MRI applications will be provided, along with a description of the current limitations.Learning Objectives:1. Widespread applications of MRI in radiation oncology treatment planning2. Assessment of geometric distortion when MRI is utilized as one of several imaging modalities: reproducibility of patient setup and image distortion3. Application of MRI to quantify and validate motion management models4. Review obstacles to clinical utilization of magnetic resonance spectroscopic imaging (MRSI)Research sponsored by Siemens Medical Solutions
WE‐C‐211A‐01: Requirements and Opportunities for Maintenance of Certification
Authors: Ibbott G , Frey G , Morin R , Thomas S 
Published: April 2010

The ABR began issuing time‐limited certificates for physicists in 2002. As a result, many physicists are two‐thirds the way through their MOC cycles, and should have reached several milestones by now. This course will discuss the origins of the MOC program, the requirements for physicists, and some of the opportunities available for meeting the requirements. Specific information will be provided to help physicists understand how they can satisfy the requirements for professional standing, through licensure or attestation; life‐long learning and self assessment, through the accumulation of continuing education credits, self‐assessment modules (SAMs) and self‐directed educational projects (SDEPs); cognitive expertise, through participation in a cognitive exam; and assessment of performance in practice, through the conduct of a practice quality improvement (PQI) program. Examples of each aspect will be given. Use of the personal database (PDB) provided by the ABR for each diplomate to facilitate the MOC process will be described, and the opportunities for guidance in accomplishing SDEPs and PQI projects will be presented.Learning Objectives:1. Understand the maintenance of certification program, its history and requirements.2. Learn about opportunities for satisfying the MOC requirements.3. Become familiar with sources of assistance from the ABR, including the personal database.4. Identify opportunities for guidance from sources such as the AAPM.
WE‐D‐213A‐01: Establishing a Stereotactic Body Radiation Therapy (SBRT) Clinical Program, Part 1: Physics and Dosimetry
Authors: Lovelock D , Benedict S 
Published: April 2010

Stereotactic body radiation therapy (SBRT) is a technique in which dose is delivered using either in a single fraction or a hypo‐fractionated schedule. The technique is characterized by the use of high doses per fraction, increased spatial accuracy of the radiation delivery, and a rapid fall‐off of dose outside the treatment volume. The overall goal is to minimize the direct effects of radiation on the surrounding normal tissue while delivering a dose biologically equivalent (or greater) to several weeks of conventionally fractionated radiation therapy to the treatment volume. The intent of SBRT treatment has been to deliver noninvasive tumor‐ablative doses to sharply demarcated lesions so that clinical outcomes comparable to surgery could be achieved without surgical complications. The majority of published clinical data describes the treatment of lung, liver and spinal tumors. The radiobiology of short‐course, high‐dose‐per‐fraction regimens suggests that utilizing SBRT, with significant local dose escalation even to curative doses, is feasible. The number of fractions and total doses currently in clinical use varies widely in the literature, typically ranging from 60 Gy delivered in 10 fractions to 30 Gy delivered in a single fraction.The Physics and Dosimetry section of the session is to advise medical physicists establishing such a program. The presentation will include an overview of the AAPM Task Group No. 101 on recommendations for SBRT, which has been charged with (1) review the literature and identify the range of historical experiences, reported clinical findings and expected outcomes, (2) review the relevant commercial products and associated clinical findings for an assessment of system capabilities and technology limitations, (3) determine required criteria for setting‐up and establishing an SBRT facility, including protocols, equipment, resources, and QA procedures, and (4) to develop consistent documentation for prescribing, reporting, and recording SBRT treatment delivery.Learning Objectives:1. Present the recommended guidelines on establishing an SBRT clinic as presented in the current version of the AAPM Task Group No. 101.2. Present the technical issues for clinical implementation of SBRT equipment, space considerations, time and personnel considerations.3. Review the commercial products commonly employed for SBRT with regard to image guidance, localization devices, patient alignment and verification systems4. Understand the limitation of some treatment planning systems and dose calculation alogorithms as they apply to the highly heterogenous doses within a small target volume typically planned for SBRT.5. Review the overall quality assurance procedures for systems and patient specific parameters for SBRT deliveries.
WE‐E‐BRD‐05: EGSnrc Benchmarking Against High‐Precision Lateral Distributions of X‐Rays Produced in Thick Targets
Authors: Cojocaru C , Ross C , McEwen M , Faddegon B 
Published: April 2010

Purpose: The EGSnrc Monte Carlo code was benchmarked against newly measured angular distributions of x‐rays produced by electron beams stopping in thick targets. Method and Materials: The electron beam was generated using the National Research Council Canada (NRC) Vickers linear accelerator. Five materials: Be, Al, Cu, Ta and Pb, were used as targets and measurements were made at 20 MeV. The absolute absorbed dose was measured at different lateral positions with various ionization chambers (PTW 30013, Exradin A19, and NE2505/3) using various build‐up caps made of PMMA, Brass, Cu, Sn and W alloy. The BEAMnrc code was used to simulate the experimental setup. The geometry, beam and material properties were implemented in BEAMnrc, while the “cavity” user code was used to score the absorbed dose in the ionization chamber air cavity per incident electron up to angles of 25°. Results: For medium‐Z targets the shape agreement between measured and simulated distributions is better than 1 % for the entire scanning range. In terms of absolute dose, it was found that there are differences of up to 4 % related to the build‐up caps used for the ionization chamber. When considering the five targets, a trend with Z of the target material is noticed. For medium‐Z targets the ratio of calculated to measured dose has a variation below 1 %, for the Be target the ratio increases 12 % with the scanning position, while for the Pb target the ratio decreases 5 %. Conclusion: The present study shows that the EGSnrc code predicts x‐ray angular distributions with shapes in agreement with the measured data at the 1 % level for medium‐Z targets. There are still unresolved discrepancies in the absolute dose related to the build‐up cap used for the ionization chamber and the target material.Partial support from NIH R01 CA104777‐01A2.
WE‐E‐213A‐03: Practical Aspects of Commissioning and Calibration of Clinical Orthovoltage Units
Authors: Abdel‐Rahman W , Liang L , AlDahlawi I , Seuntjens J 
Published: April 2010

Despite the emphasis on megavoltage radiation therapy, kV units are still being acquired and used in clinical radiation therapy for superficial lesions and specialized treatment techniques. The dosimetry of kV X‐ray beams is tricky and subject to increased uncertainties due to the energy dependence of many quantities involved in determination of absorbed dose at the reference point. In addition, there are a large variety of beam modifiers and applicators used each of which requires separate relative output measurements sometimes affected by issues such as electron contamination and scatter. This presentation concentrates on the practical aspects of a typical clinical AAPM TG61 protocol implementation. Following aspects will be discussed: (1) a review of the calibration protocol formalism; (2) ionization chamber types and calibration; (3) beam quality measurements; (4) relative measurements for open and closed applicators; (5) other clinical aspects such as tertiary collimation, etc.Educational goals:1. understanding of the concepts and formalism of the TG61 protocol2. understanding the characteristics of ionization chambers with respect to kV dosimetry3. elucidating aspects of the commissioning of orthovoltage units4. illustrating special clinical situations
TH‐SAM‐BRB‐01: HDR and LDR Brachytherapy: Everything You Need to Know
Authors: Thomadsen B , Miller R 
Published: April 2010

The development of Brachytherapy began about 1899 following the purification of radium by Pierre and Marie Curie and has been developing rapidly and continually since. The focus of this presentation will be on the most common current utilizations and aspects that present new and controversial issues: brachytherapy applications in breast, prostate, intra‐operative lung and for macular degeneration; electronic brachytherapy, error management and reduction; and some quality management issues. The discussion will consider how the physical nature of brachytherapy enhances and limits the treatments. A list of resources will be provided covering the basics and history of Brachytherapy.Learning Objectives:1. Compare and contrast the advantages of LDR vs. HDR in the treatment of prostate cancer2. Compare electronic brachytherapy to traditional brachytherapy3. Review the more recent brachytherapy options for the treatment of breast cancer4. Introduce brachytherapy for intra‐operative lung and macular degeneration5. Review management of errors and reporting in brachytherapy and how to perform a root cause analysis6. Review guidelines for quality assurance
TH‐A‐BRD‐01: The Future of NIH Research Funding
Authors: Kitt C , Williamson J , Paganetti H 
Published: April 2010

The National Institute of Health (NIH) is the most important source for funding medical physics research in the US. Consequently it has a profound impact on careers in medical physics. Most medical physicists rely on NIH funding to support their research ideas and launch or maintain research projects. While innovative research ideas are a pre‐requisite to attract funding, it is also important to understand the mechanisms of grant application.For this year the NIH has made significant changes to its grant review and submission process. These changes were driven by three aims:1. Engage the Best ReviewersReviewing grant applications can be a huge burden for scientists. Consequently, new reviewers will be given additional flexibility regarding their tour of duty. Further, efforts will be undertaken to improve retention of standing review members. Studies will be conducted on the feasibility of using high‐bandwidth support for review meetings to provide greater flexibility and alternatives for in‐person meetings.2. Improve the Quality and Transparency of ReviewA new criterion‐based scoring on a 1‐7 scale, using structured critiques, will be introduced. The reviewers will provide feedback through scores and critiques for each criterion in a structured summary statement. Streamlined applications will receive a preliminary score. Applications will be shortened significantly to for example a 12‐page research plan for an R01 application.3. Ensure Balanced and Fair Reviews across Scientific Fields and Career Stages, and Reduce Administrative BurdenTo ensure that the largest number of high quality and meritorious applications receive funding earlier and to improve system efficiency, NIH is considering separate percentiling of new and resubmitted applications and permitting one amended application. NIH is establishing an Early Stage Investigator designation for which clustering of applications is considered. The same approach will be considered for clinical research applications.This educational session is divided into three presentations followed by a panel discussion with questions from the audience. It will address newcomers and established researchers. The presentations will cover the following topics:1. “Overall strategies for successful NIH grant applications.”2. “Imminent changes in the NIH grant submission and review.”3. “Impact of the changes from an applicant's point of view.”Learning Objectives:1. Understand the new NIH grant submission and review process2. Understand the imminent changes in the NIH grant submission and review process
TH‐D‐211A‐01: Reimbursement for Medical Physics Services
Authors: Goodwin J 
Published: April 2010

As health care costs continue to escalate and reimbursements rates tighten, medical physicists must be prepared to demonstrate their economic value as well as their clinical value. This talk will review the major reimbursement processes that exist and the fundamental differences in how payment rates are established for hospital outpatient departments, free standing facilities and physicians. The CPT® coding system will be reviewed with special emphasis on the Continuing Medical Physics Consultation code 77336 and the Special Medical Radiation Physics Consultation code 77370. Proper reporting documentation will be discussed. Sources of information on reimbursement and coding will be identified. Finally, current activities of the AAPM Professional Economic Committee will be highlighted.Learning Objectives:1. To understand the major reimbursement systems and how payment rates are established2. To understand the CPT® coding system and the need for proper documentation in the clinic3. To identify authoritative sources of reimbursement and coding information4. To learn about AAPM PEC activities and how they benefit the membership
Association of Missense Mutations in Epoxyalkane Coenzyme M Transferase with Adaptation of
Mycobacterium
sp. Strain JS623 to Growth on Vinyl Chloride
Authors: Jin Yang Oh , Cheung Samantha , Coleman Nicholas V. , Mattes Timothy E. 
Published: April 2010

ABSTRACT

Vinyl chloride (VC) is a toxic groundwater pollutant associated with plastic manufacture and chlorinated solvent use. Aerobic bacteria that grow on VC as a carbon and energy source can evolve in the laboratory from bacteria that grow on ethene, but the genetic changes involved are unknown. We investigated VC adaptation in two variants (JS623-E and JS623-T) of the ethene-oxidizing
Mycobacterium
strain JS623. Missense mutations in the EtnE gene developed at two positions (W243 and R257) in cultures exposed to VC but not in cultures maintained on ethene. Epoxyalkane-coenzyme M transferase (EaCoMT) activities in cell extracts of JS623-E and JS623-T (150 and 645 nmol/min/mg protein, respectively) were higher than that of wild-type JS623 (74 nmol/min/mg protein), and in both variant cultures epoxyethane no longer accumulated during growth on ethene. The heterologous expression of two variant
etnE
alleles (W243G [
etnE1
] and R257L [
etnE2
]) from strain JS623 in
Mycobacterium smegmatis
showed that they had 42 to 59% higher activities than the wild type. Recombinant JS623 cultures containing mutant EtnE genes cloned in the vector pMV261 adapted to growth on VC more rapidly than the wild-type JS623 strain, with incubation times of 60 days (wild type), 1 day (pMV
etnE1
), and 35 days (pMV
etnE2
). The JS623(pMV
etnE
) culture did not adapt to VC after more than 60 days of incubation. Adaptation to VC in strain JS623 is consistently associated with two particular missense mutations in the
etnE
gene that lead to higher EaCoMT activity. This is the first report to pinpoint a genetic change associated with the transition from cometabolic to growth-linked VC oxidation in bacteria.
Epidemiology of Seafood-Associated Infections in the United States
Authors: Iwamoto Martha , Ayers Tracy , Mahon Barbara E. , Swerdlow David L. 
Published: April 2010

SUMMARY
Seafood is part of a healthful diet, but seafood consumption is not risk-free. Seafood is responsible for an important proportion of food-borne illnesses and outbreaks in the United States. Seafood-associated infections are caused by a variety of bacteria, viruses, and parasites; this diverse group of pathogens results in a wide variety of clinical syndromes, each with its own epidemiology. Some seafood commodities are inherently more risky than others, owing to many factors, including the nature of the environment from which they come, their mode of feeding, the season during which they are harvested, and how they are prepared and served. Prevention of seafood-associated infections requires an understanding not only of the etiologic agents and seafood commodities associated with illness but also of the mechanisms of contamination that are amenable to control. Defining these problem areas, which relies on surveillance of seafood-associated infections through outbreak and case reporting, can lead to targeted research and help to guide control efforts. Coordinated efforts are necessary to further reduce the risk of seafood-associated illnesses. Continued surveillance will be important to assess the effectiveness of current and future prevention strategies.
Selective Depletion of
Sulfolobus solfataricus
Transcription Factor E under Heat Shock Conditions
Authors: Iqbal Junaid , Qureshi Sohail A. 
Published: April 2010

ABSTRACT

Archaeal transcriptional machinery is similar to that of eukaryotes. We studied the fates of various components of the
Sulfolobus solfataricus
transcriptional apparatus under different stresses and found that in cells incubated at 90°C for 1 h, transcription factor E (TFE) is selectively depleted, but its mRNA levels are increased. We discuss the implications of these findings.