Clinical Medical Physicists Research Articles

TH-A-134-01: Breast Imaging QA

Implementation of a New Breast Tomosynthesis Program: A Clinical Medical Physicist's Experience-W Geiser Digital breast tomosynthesis (DBT) was approved by the FDA as a screening tool for breast cancer in February 2011. Many systems were preinstalled as 2D systems and are now being upgraded for DBT and there is evidence that DBT is helping reduce recall rates while increasing cancer detection rates. As of February 2013 there were approximately 500 systems certified by the FDA for DBT and it is expected that there will be more than 700 certified systems by the third quarter of 2013. Facilities implementing a breast tomosynthesis program need to be aware that there are many hurdles to be overcome before tomosynthesis studies can be performed. The purpose of this lecture is to provide medical physicists assisting facilities that are upgrading 2D systems or installing new DBT systems, the knowledge to assist with facility design, image storage requirements, choice of PACS, and optimization of diagnostic review. New educational requirements for medical physicists to qualify to perform acceptance testing and continued annual testing of DBT systems will also be reviewed. Learning Objectives: 1. Be able to assist with implementation of breast tomosynthesis at their facility. 2. Know the process for accreditation and certification of DBT systems. 3. Understand additional shielding requirements and facility design for a facility installing digital breast tomosynthesis. Breast MR Imaging and Quality Control — D Reeve MR imaging of the breast is an important adjunct to mammography and ultrasound for the detection of breast cancer and for breast biopsy guidance. Diagnostic breast MRI protocols typically include T2-weighted fat saturated images and 3D T1-weighted dynamic contrast enhanced (DCE) multiphase images using a Gadolinium-based contrast agent. The DCE images are used to determine the kinetic signature of enhancing tissues in order to differentiate between benign and malignant lesions. MR spectroscopy and diffusion weighted images (DWI) may also be acquired in order to provide additional diagnostic information. The diagnostic value of breast MRI scans can be improved by choosing acquisition parameters that optimize image quality parameters such as SNR, contrast and spatial resolution. As with any MRI protocol, achieving the desired image quality must balance the need for acceptable scan times. The timing and temporal resolution of the DCE series are important considerations. Breast radiofrequency (RF) coils are phased array coils capable of simultaneous bilateral imaging. A comprehensive breast MRI quality control program is important to assess the performance of the MRI system as well as the breast RF coils. Learning Objectives: 1. Provide an overview of breast MR imaging and MR-guided biopsy procedures. 2. Describe breast MR image quality criteria and protocol optimization. 3. Discuss the components of a breast MRI quality control program.

IAEA contribution to international harmonization of guidelines for clinical medical radiation physicists

The IAEA's Technical Cooperation Project INT/6/054 “Strengthening Medical Physics in Radiation Medicine” aims at promoting the recognition of medical physics in radiation medicine and to harmonize educational and clinical training requirements in order to achieve the required standard of patient care in radiation medicine. To achieve this project's objective, the IAEA's efforts were supported by numerous stakeholders from medical physics professional societies and regional counterparts from Europe, Africa, Latin America and Asia. Within this project, the IAEA established four Working Groups (WGs) to address the issues of (i) roles and responsibilities, (ii) education & clinical training requirements, (iii) staffing requirements and (iv) raising awareness on the medical physics profession. The WG1 and WG2 drafted the guidelines on roles and responsibilities, and education & clinical training requirements for clinical medical physicists. The guidelines were compiled into a single report, aiming at providing recommendations on the minimum requirements for the academic education and clinical training necessary for a physicist to become a clinically qualified medical physicist. They include recommendations for accreditation, certification and registration, along with continuous professional development. With the purpose of establishing the grounds for substantiating the recommendation on education and clinical training requirements, the IAEA report includes first the roles and responsibilities of a clinically qualified medical physicist in radiation medicine. The goal of the IAEA report is to establish criteria that support the harmonization of education and clinical training worldwide, as well as promoting the recognition and professionalism of medical physics as a profession internationally. The IAEA report was endorsed by the International Organization for Medical Physics (IOMP) and approved for publication as an IAEA Human Health Report. The main recommendations included in the IAEA report will be presented, together with preliminary plans to support implementation, especially in low and middle income countries. 1 IAEA, 2 Portugal, IOMP, 3 Hong Kong, China, IOMP, 4B.O.Cyprus Oncology Centre, Cyprus, 5 Karolinska University Hospital, Sweden, 6 Mexico, ALFIM, 7 Colombia, ALFIM, 8 Nigeria, FAMPO, 9 USA, AAPM

WE‐G‐137‐01: Medical Physics Economics

This presentation will review the aspects of medical physics economics and reimbursement that are relevant to the practicing clinical medical physicist. Covered topics will include:CPT© code development, valuation and useMedicare payment systems: Hospital Outpatient Prospective Payment System, Medicare Physician Fee Schedule and Ambulatory Surgical CentersGeneral coding and billing practicesUpcoming changes in reimbursementSources of informationAAPM economic activitiesKnowledge of these topics is essential to the practicing physicist to ensure that his/her work is recognized and billed for correctly. The presentation will not be a comprehensive billing seminar as coverage policies vary with location. However, general guidelines will be reviewed and sources of authoritative billing information will be included.Learning Objectives:1. Understand the three primary Medicare reimbursement systems, how they differ in coverage and in the way they determine reimbursement levels.2. Understand how CPT© codes are utilized to report billable work.3. Understand where to find authoritative billing and coding information.

WE‐F‐WAB‐01: Safety Improvement Through Incident Learning

Incident learning is a key tool for improving the quality and safety of procedures. Its use has been linked to better patient‐safety outcomes. This session is designed to provide practical advice to the clinical medical physicist on how to run a successful incident learning system in radiation oncology. The session will draw on engaging examples from clinical practice and will focus on the relevance to smaller clinics. The session will include a presentation from a leading physician on clinical perspectives on quality and safety improvement. The session will also introduce the new national incident reporting system being developed by AAPM and ASTRO. This program employs the Patient Safety Organization (PSO) structure. The concept and structure of the PSO system will be discussed by an expert in the field.Learning Objectives:1. Appreciate the value of incident learning for improving patient safety2. Understand the difference between incident learning at the institutional level vs. the national level, and recognize the issues unique to each3. Learn about the new national radiation oncology incident learning system developed by AAPM and ASTRO

TU‐G‐116‐01: A Roadmap for Installing and Commissioning New Equipment

Learning Objectives:1. To learn how to build a new equipment commissioning project plan using efficient project management methods2. To identify equipment, personnel resources and commissioning time required3. Understand how to account for commissioning new technology with small install base4. Learn to develop a representative commissioning plan for a linac, CK, HDR unit or treatment planning system. Commissioning a large new piece of equipment or software is a core responsibility for a clinical medical physicist, yet it can be a daunting undertaking. Increasingly complex technology requires more complex, commissioning tasks to be completed. Many of these tasks originate from recently published AAPM Task Groups, but there is not yet a good sense in the community of how much time these tasks typically require. Medical Physicists are required to do all recommended tests to ensure patient safety while at the same time being conscious of revenue loss during commissioning time. Therefore, commissioning time needs to budgeted within a fairly tight tolerance.This session will give audiences the tool to develop a commissioning plan including time required, equipment needs, staff needs, and commissioning checklist. The speakers will demonstrate how to develop a sample commissioning plan for a linac, CyberKnife, HDR unit and treatment planning system.

WE‐C‐137‐01: Professional Liability and Risk Management in Medical Physics Practice

Medical physicists can be exposed to significant liability risks when performing clinical duties. The nature and extent of such exposure is not always as clear to physicists as it is to physicians. The legal questions involved in resolving a case or claim involving patient harm are complex and are seldom governed according to common sense expectations. Whether a physicist is employed by a hospital or healthcare provider or functions independently as a contractor or consultant, the first line of defense against liability risk is contract negotiation. In this process, the physicist has the opportunity to establish a respectful, collaborative relationship with an employer or client while laying out clear rules and expectations for the handling of any incidents. Much legal, financial, and professional trouble can be avoided by handling this process carefully. This session explores methods and principles for establishing good relationships and contracts. Should a lawsuit occur, it is important to have a basic understanding of civil procedure and the “anatomy” of a professional liability case. This session will review common legal terminology and present examples from seminal cases that are used as the basis of many liability and malpractice cases today. In the event that a physicist is named as a defendant in a lawsuit, he or she should be well‐informed about the expected sequence of events and how they relate to the overall outcome of the case. Professional liability insurance is a useful tool to provide protection to an individual physicist's personal assets and income in the event of a lawsuit, and especially after an adverse legal decision or settlement. The choice of the appropriate amount and type of protection is an individual and complicated decision. Some employers of physicists also provide coverage to their employees, and the nature and extent of this coverage can be challenging to understand fully. This session discusses the common features and aspects of professional liability insurance products to enable the clinical medical physicist to evaluate their own situation and to choose an appropriate product for their needs.Learning Objectives:1. Describe a strategy for medical physicists to minimize liability risk by establishing and negotiating healthy contract relationships with employers or clients.2. Recognize the common elements of civil procedure and explain how they are impacted by typical clinical medical physics activities, such as quality control and recordkeeping.3. Evaluate commercial professional liability insurance offerings in the context of a physicist's personal asset and income protection needs and practice type and setting.

Workload and transmission data for the installation of a digital breast tomosynthesis system

Digital breast tomosynthesis (DBT) differs from conventional mammography in target/filter, kVp range, and imaging geometry. The aim of this study was to assess the breast input exposure of a DBT system by completing a workload survey of DBT installations, and to determine the parameters α, β, and γ in the Archer equation for the primary radiation generated by the clinical workload distributions. The authors conducted a retrospective survey of the x-ray breast imaging performed between September 2011 and September 2012 in three clinical DBT rooms equipped with Selenia Dimensions systems (Hologic Inc., Bedford, MA). A total of 343 examinations were analyzed to calculate the workload (mA-minute) and the primary air kerma at 1 m from the source (K(1)). Transmission curves were calculated for the primary radiation generated by the workload distributions of the DBT rooms, and were fitted to the Archer equation. There were large variations in patient volume and workload in the three examination rooms. In all these rooms, the average tube voltage (kVp) was about 31, the average K(1) per patient was 16-21 mGy, and the average mA-minute per patient was 1.4-2.2 times higher than that of the mammography room described in NCRP Report No. 147. Most DBT screening examinations consisted of four two-dimensional mammographic views plus four tomosynthesis scans; the numbers of views acquired in diagnostic examinations varied widely. Tomosynthesis scans contributed about 30% of total mA-minute and about 50% of K(1). For the primary radiation generated by the clinical workload distributions, α was similar to that of 40-45 kVp W/Al (target/filter), and α + β was similar to that of 30 kVp W/Al. The workload (mA-minute and K(1)) distributions of mammographic examinations with DBT differ from conventional mammography. A field survey of patient volume and x-ray tube usage is important for the shielding design of DBT facilities. The clinical workloads and transmission data presented in this paper may be useful for clinical medical physicists.

AFOMP Policy Statement No. 4: recommendations for continuing professional development systems for medical physicists in AFOMP countries

This policy statement, which is the fourth of a series of documents being prepared by the Asia-Oceania Federation of Organizations for Medical Physics Committees Professional Development Committee, gives guidance on how member countries could develop a continuing professional development system for ensuring that its clinical medical physicists are up-to-date in their knowledge and practice. It is not intended to be prescriptive as there are already several CPD systems successfully operated by AFOMP member countries and elsewhere that vary considerably in scope and structure according to local culture, practice and legislation but all of which are capable of ensuring that physicists are up-to-date. It is intended to be advisory and set out options for member countries to develop their individual CPD systems.

TOPAS: An innovative proton Monte Carlo platform for research and clinical applications

While Monte Carlo particle transport has proven useful in many areas (treatment head design, dose calculation, shielding design, and imaging studies) and has been particularly important for proton therapy (due to the conformal dose distributions and a finite beam range in the patient), the available general purpose Monte Carlo codes in proton therapy have been overly complex for most clinical medical physicists. The learning process has large costs not only in time but also in reliability. To address this issue, we developed an innovative proton Monte Carlo platform and tested the tool in a variety of proton therapy applications. Our approach was to take one of the already-established general purpose Monte Carlo codes and wrap and extend it to create a specialized user-friendly tool for proton therapy. The resulting tool, TOol for PArticle Simulation (TOPAS), should make Monte Carlo simulation more readily available for research and clinical physicists. TOPAS can model a passive scattering or scanning beam treatment head, model a patient geometry based on computed tomography (CT) images, score dose, fluence, etc., save and restart a phase space, provides advanced graphics, and is fully four-dimensional (4D) to handle variations in beam delivery and patient geometry during treatment. A custom-designed TOPAS parameter control system was placed at the heart of the code to meet requirements for ease of use, reliability, and repeatability without sacrificing flexibility. We built and tested the TOPAS code. We have shown that the TOPAS parameter system provides easy yet flexible control over all key simulation areas such as geometry setup, particle source setup, scoring setup, etc. Through design consistency, we have insured that user experience gained in configuring one component, scorer or filter applies equally well to configuring any other component, scorer or filter. We have incorporated key lessons from safety management, proactively removing possible sources of user error such as line-ordering mistakes. We have modeled proton therapy treatment examples including the UCSF eye treatment head, the MGH stereotactic alignment in radiosurgery treatment head and the MGH gantry treatment heads in passive scattering and scanning modes, and we have demonstrated dose calculation based on patient-specific CT data. Initial validation results show agreement with measured data and demonstrate the capabilities of TOPAS in simulating beam delivery in 3D and 4D. We have demonstrated TOPAS accuracy and usability in a variety of proton therapy setups. As we are preparing to make this tool freely available for researchers in medical physics, we anticipate widespread use of this tool in the growing proton therapy community.

Dosimetry of 125I and 103Pd COMS eye plaques for intraocular tumors: Report of Task Group 129 by the AAPM and ABS

Dosimetry of eye plaques for ocular tumors presents unique challenges in brachytherapy. The challenges in accurate dosimetry are in part related to the steep dose gradient in the tumor and critical structures that are within millimeters of radioactive sources. In most clinical applications, calculations of dose distributions around eye plaques assume a homogenous water medium and full scatter conditions. Recent Monte Carlo (MC)-based eye-plaque dosimetry simulations have demonstrated that the perturbation effects of heterogeneous materials in eye plaques, including the gold-alloy backing and Silastic insert, can be calculated with reasonable accuracy. Even additional levels of complexity introduced through the use of gold foil "seed-guides" and custom-designed plaques can be calculated accurately using modern MC techniques. Simulations accounting for the aforementioned complexities indicate dose discrepancies exceeding a factor of ten to selected critical structures compared to conventional dose calculations. Task Group 129 was formed to review the literature; re-examine the current dosimetry calculation formalism; and make recommendations for eye-plaque dosimetry, including evaluation of brachytherapy source dosimetry parameters and heterogeneity correction factors. A literature review identified modern assessments of dose calculations for Collaborative Ocular Melanoma Study (COMS) design plaques, including MC analyses and an intercomparison of treatment planning systems (TPS) detailing differences between homogeneous and heterogeneous plaque calculations using the American Association of Physicists in Medicine (AAPM) TG-43U1 brachytherapy dosimetry formalism and MC techniques. This review identified that a commonly used prescription dose of 85 Gy at 5 mm depth in homogeneous medium delivers about 75 Gy and 69 Gy at the same 5 mm depth for specific (125)I and (103)Pd sources, respectively, when accounting for COMS plaque heterogeneities. Thus, the adoption of heterogeneous dose calculation methods in clinical practice would result in dose differences >10% and warrant a careful evaluation of the corresponding changes in prescription doses. Doses to normal ocular structures vary with choice of radionuclide, plaque location, and prescription depth, such that further dosimetric evaluations of the adoption of MC-based dosimetry methods are needed. The AAPM and American Brachytherapy Society (ABS) recommend that clinical medical physicists should make concurrent estimates of heterogeneity-corrected delivered dose using the information in this report's tables to prepare for brachytherapy TPS that can account for material heterogeneities and for a transition to heterogeneity-corrected prescriptive goals. It is recommended that brachytherapy TPS vendors include material heterogeneity corrections in their systems and take steps to integrate planned plaque localization and image guidance. In the interim, before the availability of commercial MC-based brachytherapy TPS, it is recommended that clinical medical physicists use the line-source approximation in homogeneous water medium and the 2D AAPM TG-43U1 dosimetry formalism and brachytherapy source dosimetry parameter datasets for treatment planning calculations. Furthermore, this report includes quality management program recommendations for eye-plaque brachytherapy.

Overview on the dosimetric uncertainty analysis for photon-emitting brachytherapy sources, in the light of the AAPM Task Group No 138 and GEC-ESTRO report

In 2011, the American Association of Physicists in Medicine (AAPM) and the Groupe Européen de Curiethérapie–European Society for Radiotherapy and Oncology (GEC-ESTRO) published a report pertaining to uncertainties in brachytherapy single-source dosimetry preceding clinical use. The International Organization for Standardization's Guide to the Expression of Uncertainty in Measurement and Technical Note 1297 by the National Institute of Standards and Technology are taken as reference standards for uncertainty formalism. Uncertainties involved in measurements or Monte Carlo methods to estimate brachytherapy dose distributions are provided with discussion of the components intrinsic to the overall dosimetric assessment. The uncertainty propagation from the primary calibration standard through transfer to the clinic for air-kerma strength is given with uncertainties in each of the brachytherapy dosimetry parameters of the AAPM TG-43 dose-calculation formalism. For low-energy and high-energy brachytherapy sources of low dose-rate and high dose-rate, a combined dosimetric uncertainty <5% (k = 1) is estimated, which is consistent with prior literature estimates. Recommendations are provided for clinical medical physicists, dosimetry investigators, and manufacturers of brachytherapy sources and treatment planning systems. These recommendations reflect the guidance of the AAPM and GEC-ESTRO for their members, and may also be used as guidance to manufacturers and regulatory agencies in developing good manufacturing practices for conventional brachytherapy sources used in routine clinical treatments.

SU-E-E-04: Building and Strengthening the First Master's Program in Medical Physics in The Gulf Region.

The first medical physics Master's program in the Arabian Gulf region was started in 2002 at King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, Saudi Arabia. After consulting with national and international representatives from the AAPM, IOMP, the University of Wisconsin-Madison and King Faisal Specialist Hospital and Research Center (KFSHRC) we constructed a versatile and rigorous curriculum. The program requires the completion of 7 core courses, 7 required labs, a minimum of 3 elective courses, a research project, a four-month clinical rotation and passing and a comprehensive examination. The success of the program required very close collaboration with national hospitals such as King Fahad Specialist Hospital in Dammam (KFSH-D), KFSHRC, and Riyadh Military Hospital. We cemented the collaboration with a formal agreement between KFUPM and KFSH-D, whereby the clinical medical physicists are actively involved in teaching lectures and labs, evaluating students' performance and co-supervising their clinical rotation and research projects. In order to prepare our graduates for their medical physics careers, we emphasize innovative learning methods such as students centered learning, execution of course projects, experiential learning and acquiring research skills and tools such as Monte Carlo simulations. Our graduates have succeeded in securing clinical positions in some of the best hospitals in the region and achieved high employer satisfaction. Some students have gone to pursue their PhD's in North America and Europe. Many of our students succeeded in publishing their projects in international journals and international conferences. One of our students was instrumental in obtaining a US patent (US Patent # 785298) for an innovative x-ray tube design. We have achieved national recognition through the excellence of our graduates. In order to maintain high education quality standards and achieve international recognition, we are presently working to acquire IAEA approval and CAMPEP accreditation.

WE-G-BRA-05: Simulated Troubleshooting Session for Medical Physics Resident Rotations.

Troubleshooting is a difficult to train, but critical skill for a clinical medical physicist. It is unlikely that residents will have opportunities to troubleshoot many real clinical scenarios during a typical 3 month rotation. The ability to analyze and correct abnormal clinical situations is imperative to providing safe radiation therapy care. We have developed a novel strategy to train medical physics residents to gain such important clinical physics skill. Simulated troubleshooting sessions were designed for each rotation, featuring problematic clinical scenarios. The resident was required to troubleshoot each scenario in a given time frame. Using a brachytherapy rotation as an example, the transfer tubes connecting the afterloader to the Tandem and Ovoids (T&O) applicators were purposely inserted incorrectly. The resident was asked to deliver a dummy T&O plan in a reasonable time frame including troubleshooting all problems that may occur. Many simulated troubleshooting situations were presented to the resident. Two residents went through a 3 month brachytherapy rotation, one with and the other without the simulated troubleshooting session. All other rotation activities were the same. At the end of the rotation, an oral exam was given to test how well the residents understood the brachytherapy clinical practice. Both residents were able to pass the exam. However, the resident that received the troubleshooting session performed better'‴a superior understanding of the reasons behind the clinical practice and better troubleshooting skills were demonstrated. To train residents to better handle the clinical situations, it is important to include a simulated troubleshooting session into clinical rotations. Simulated troubleshooting sessions are excellent and necessary supplements to the clinical rotations for the residents to gain practical clinical skills.

SU-E-I-10: Putting Teeth into Your CT Dosimetry Program: Approaches to Cone- Beam Dental/Maxillofacial CT Dosimetry.

To review and compare different approaches to the problem of dosimetry for limited field-of-view (FOV) cone beam CT devices for dental and maxillofacial applications. The determination of patient doses from specialized, cone-beam CT devices for dental and maxillofacial work requires medical physicists to re-evaluate their dosimetry methods. These devices work in cone-beam geometry, with an axial field dimension on the order of the lengths of the standard head CTDI phantom and pencil ionization chamber. They may also utilize less than 360 degree scans, resulting in asymmetrical radiation distributions. This operating regime is far from that for which conventional CT dosimetry was designed, and alternative approaches must be considered. The alternatives include extensions of conventional CT dosimetry currently used for large axial FOV scanners (e.g. the extended CTDI parameter (CTDIe) for the Toshiba Aquillion One with 160 mm axial FOV) and the new method based on point dosimetry measurements recently formalized in AAPM Report TG-111. Conventional, modified-conventional, and TG-111 dosimetry measurements are used in two CT dose phantoms (adult head and pediatric head) to obtain dose indices for the Planmeca ProMax 3D Max dental CT scanner. Surface dose maps are generated using radiochromic film for correlation with the chamber dosimetry. Results for the three dosimetry approaches are compared for the specific case of the ProMax 3D Max scanner. Strengths and weaknesses of the three measurement paradigms for this type of application are compared. The increasing availability of specialized scanners operating in full cone-beam mode will require the clinical medical physicist to be conversant with extensions to the CT dose index methodology suitable for this equipment.

WE‐A‐213AB‐01: Second Cancers from Radiation Therapy Procedures

Second Cancers are the most common late effect among long‐term cancer survivors. Radiation has been a known risk factor for cancer induction based on atomic bomb survivor follow‐up. Over the last few decades, there has also been increasing data on second cancers in medically exposed populations, particularly radiotherapy patients. As treatments become more successful and patients survive longer after treatment, long‐term patient health considerations must play an increasing role in the selection of treatment. To this end, it is important that the field of medical physics become well educated in issues related to long‐term radiotherapy sequelae, including second cancers. The session chair will give an overview of retrospective dose reconstruction method commonly used in these large cohort studies second cancers in patients treated with radiation therapy. Understanding the dosimetry in these studies will provide a better understanding of the results of the studies, the dose response models, and gaps in knowledge regarding dose volume effects. In the remainder of the presentation, the speaker will focus on the current state of knowledge of second cancers, specifically focusing on information and limitations of the available literature. This will include the magnitude of risk of second cancers, including the impact of different demographics. It will also include etiological discussions, focusing on the risk attributable to radiation. This presentation will include the available data on the dose response of second cancers, including the large uncertainties inherent to both low and high dose regions. It will also highlight dosimetry for advanced radiotherapy techniques, and what associated doses might mean for the second cancer risk. Finally, the presentation will discuss examples of how second cancer risk can be reduced in routine clinical practice. Learning Objectives: increase the knowledge of clinical medical physicists regarding radiation‐ induced second cancers as well as stimulate further research in this broad and increasingly important area.Learning Objectives:1. To provide general overview of the dose reconstruction methods used in epidemiological retrospective cohort studies of radiation related late effects.2. To improve the understanding of the magnitude of the second cancer risk faced by radiotherapy patients.3. To improve the understanding of the etiology of second cancers.4. To present an overview of current knowledge on dose response for radiation induced second cancers.5. To discuss the impact of advanced radiotherapy techniques on the risk of second cancers6. To provide examples of how second cancer risk can be reduced in routine clinical practice.

WE-G-BRA-03: Enhancing Medical Imaging Physics Education on a Global Basis with Shared Resources.

To enhance and enrich medical imaging physics education by first translating personal professional experience into highly-effective educational resources and then sharing with both learners and medical physics educators on a global basis as an open and free resource. Effective medical imaging physics education that contributes to high-quality and safe clinical procedures requires medical physicists and students, anywhere in the world, having access to the science of contemporary imaging methods and procedures in a form that enriches both the teaching and learning activities. This is being achieved in two phases. The first (and continuing) phase is the translation of personal experience as a practicing clinical medical physicist in to a synergistic collection of educational resources including textbooks, online modules, and especially highly- effective visuals that can be used in classroom presentations and small group discussions. It is the availability of these visuals that enhances the performance of medical physicists as teachers who can devote their efforts to guiding the class learning activities and sharing their personal experiences and not be burdened with the production of extensive teaching materials. The second (and overlapping) phase is the development of a model and method for sharing as an open and free resource. This is achieved through a web site developed for that purpose, www.(blinded for review).org. These resources are used to support medical physics educators, programs, and individual learners both in the US and in over 100 different countries with an average of over 1000 users each day. The production and sharing of educational resources by an individual medical physicist complements and extends beyond the programs and activities of institutions and organizations. It is of significant value to learners anywhere in the world because the availability is not limited by costly course enrollment, membership, meeting registration, or geographic restrictions.

Functionality and operation of fluoroscopic automatic brightness control/automatic dose rate control logic in modern cardiovascular and interventional angiography systems: A Report of Task Group 125 Radiography/Fluoroscopy Subcommittee, Imaging Physics Committee, Science Council

Task Group 125 (TG 125) was charged with investigating the functionality of fluoroscopic automatic dose rate and image quality control logic in modern angiographic systems, paying specific attention to the spectral shaping filters and variations in the selected radiologic imaging parameters. The task group was also charged with describing the operational aspects of the imaging equipment for the purpose of assisting the clinical medical physicist with clinical set-up and performance evaluation. Although there are clear distinctions between the fluoroscopic operation of an angiographic system and its acquisition modes (digital cine, digital angiography, digital subtraction angiography, etc.), the scope of this work was limited to the fluoroscopic operation of the systems studied. The use of spectral shaping filters in cardiovascular and interventional angiography equipment has been shown to reduce patient dose. If the imaging control algorithm were programmed to work in conjunction with the selected spectral filter, and if the generator parameters were optimized for the selected filter, then image quality could also be improved. Although assessment of image quality was not included as part of this report, it was recognized that for fluoroscopic imaging the parameters that influence radiation output, differential absorption, and patient dose are also the same parameters that influence image quality. Therefore, this report will utilize the terminology "automatic dose rate and image quality" (ADRIQ) when describing the control logic in modern interventional angiographic systems and, where relevant, will describe the influence of controlled parameters on the subsequent image quality. A total of 22 angiography units were investigated by the task group and of these one each was chosen as representative of the equipment manufactured by GE Healthcare, Philips Medical Systems, Shimadzu Medical USA, and Siemens Medical Systems. All equipment, for which measurement data were included in this report, was manufactured within the three year period from 2006 to 2008. Using polymethylmethacrylate (PMMA) plastic to simulate patient attenuation, each angiographic imaging system was evaluated by recording the following parameters: tube potential in units of kilovolts peak (kVp), tube current in units of milliamperes (mA), pulse width (PW) in units of milliseconds (ms), spectral filtration setting, and patient air kerma rate (PAKR) as a function of the attenuator thickness. Data were graphically plotted to reveal the manner in which the ADRIQ control logic responded to changes in object attenuation. There were similarities in the manner in which the ADRIQ control logic operated that allowed the four chosen devices to be divided into two groups, with two of the systems in each group. There were also unique approaches to the ADRIQ control logic that were associated with some of the systems, and these are described in the report. The evaluation revealed relevant information about the testing procedure and also about the manner in which different manufacturers approach the utilization of spectral filtration, pulsed fluoroscopy, and maximum PAKR limitation. This information should be particularly valuable to the clinical medical physicist charged with acceptance testing and performance evaluation of modern angiographic systems.

Continuing professional development systems for medical physicists: A global survey and analysis

Continuing professional development (CPD) and continuing professional education (CPE) are seen as being necessary for medical physicists to ensure that they are up-to-date with current clinical practice. CPD is more than just continuing professional education, but can include research publication, working group contribution, thesis examination and many other activities. A systematic way of assessing and recording such activities that a medical physicist undertakes is used in a number of countries. This can be used for certification and licensing renewal purposes. Such systems are used in 27 countries, but they should be implemented in all countries where clinical medical physicists are employed.A survey of the CPD systems that are currently operated around the world is presented. In general they are quite similar although there are a few countries that have CPD systems that differ significantly from the others in many respects. Generally they ensure that medical physicists are kept up-to-date, although there are some that clearly will fail to achieve that.An analysis of what is required to construct a useful medical physics CPD system is made. Finally, the need for medical physicist professional organizations to cooperate and share in the production and distribution of CPD and CPE materials is emphasized.

A simplified analytical approach to estimate the parameters required for strength determination of HDR 192Ir brachytherapy sources using a Farmer-type ionization chamber

Measuring the strength of high dose rate (HDR) (192)Ir brachytherapy sources on receipt from the vendor is an important component of a quality assurance program. Owing to their ready availability in radiotherapy departments, the Farmer-type ionization chambers are also used to determine the strength of HDR (192)Ir brachytherapy sources. The use of a Farmer-type ionization chamber requires the estimation of the scatter correction factor along with positioning error (c) and the constant of proportionality (f) to determine the strength of HDR (192)Ir brachytherapy sources. A simplified approach based on a least squares method was developed for estimating the values of f and M(s). The seven distance method was followed to record the ionization chamber readings for parameterization of f and M(s). Analytically calculated values of M(s) were used to determine the room scatter correction factor (K(sc)). The Monte Carlo simulations were also carried out to calculate f and K(sc) to verify the magnitude of the parameters determined by the proposed analytical approach. The value of f determined using the simplified analytical approach was found to be in excellent agreement with the Monte Carlo simulated value (within 0.7%). Analytically derived values of K(sc) were also found to be in good agreement with the Monte Carlo calculated values (within 1.47%). Being far simpler than the presently available methods of evaluating f, the proposed analytical approach can be adopted for routine use by clinical medical physicists to estimate f by hand calculations.

AFOMP Policy Statement No. 3: recommendations for the education and training of medical physicists in AFOMP countries

AFOMP recognizes that clinical medical physicists should demonstrate that they are competent to practice their profession by obtaining appropriate education, training and supervised experience in the specialties of medical physics in which they practice, as well as having a basic knowledge of other specialties. To help its member countries to achieve this, AFOMP has developed this policy to provide guidance when developing medical physicist education and training programs. The policy is compatible with the standards being promoted by the International Organization for Medical Physics and the International Medical Physics Certification Board.