bluuebunny/crossref_metadata_2025_split huggingface dataset:
MO‐SAMS‐332‐02: Introduction to Magnetic Resonance Spectroscopy of Breast and Prostrate Cancer: Current Applications
Authors: Jacobs MA 
Published: July 2008

Magnetic resonance spectroscopy (MRS) and magnetic resonance spectroscopy imaging (MRSI) is increasing being utilized as adjuncts for differentiating benign from malignant lesions in the clinical setting. MRS has the ability to probe intracellular metabolites, such as, choline (Cho), Creatine (Cr), citrate (Ci) and N‐acetylaspartate (NAA). The observation of a high Choline signal appears to be the spectroscopic hallmark of cancer. This additional information can be very useful in cases of indeterminate findings in suspicious lesions, for example, in breast or prostrate cancer. Indeed, recent advances have moved the use MRS into the clinical realm for detection and classification of these tumors and more importantly, monitoring response to neoadjuvant chemotherapy treatment. This presentation will review the principles of MRS, including, pulse sequences, MRS data collection, data analysis, quantification, and quality assurance. Three major topics are considered. Introduction of relevant intracellular metabolites and their biological and medical significance in cancer, the principles underlying each quantity are given. Second, major pulse sequences used for MRS, e.g., PRESS or STEAM in breast and prostrate cancer. Finally, MRS data analysis and quantification of the results with pathological observations will be also compared with MRS‐derived quantities where appropriate.This presentation is intended as an introduction to the field of MRS for anyone who desires to use the scope of modern MRS techniques, its application and use for monitoring therapy. It will be of interest to medical physicists who are considering undertaking quantitative MRS, as well as those already in the field.Educational Objectives:1. Identify the clinically important quantities (e.g. metabolites) that can be measured with MRS.2. Be familiar with the methods and techniques used for MRS acquisition.3. Basic understanding of the application of MRS to breast and prostrate cancer.
MO‐B‐342‐01: Magnitude of Medical Radiation Exposures to US Population with Focus On CT and Nuclear Medicine Doses
Authors: Mahesh M 
Published: July 2008

This presentation will examine the current trends in medical x‐ray imaging procedures in the United States. It will also examine the magnitude of radiation doses for various x‐ray imaging procedures. Special emphasis will be given to CT and nuclear medicine procedures.The results are based on the work done within the framework of National Council of Radiation of Protection Scientific Committee 6.2 formed to work on the estimation of radiation exposure to the US population from all sources. The intended goal of the Committee is to update the NCRP report 93 published in 1987. The subcommittee examined variety of data sources including commercial surveys, Medicare, Veterans Administration and insurance carrier data. Radiation exposure to the US population from medical exposures was then estimated based on the number of medical procedures grouped by modality and body parts and the radiation doses associated with each procedure.According to the preliminary results, the medical radiation exposure to US population has increased by nearly 5.5 times compared to the previous NCRP publication (NCRP 93). The largest contributor to the collective dose to US population is seen with CT and Nuclear Medicine procedures. It is found that the CT procedures accounts for 14% of all medical x‐ray imaging procedures but contribute to nearly 49% of collective dose to US population. Similarly, the nuclear medicine procedure accounts to only 4% of all procedures but contribute to nearly 26% of collective dose to US population.Educational Objectives:1. To familiarize with the types and distribution of medical imaging procedures in US.2. To learn the magnitude of medical radiation exposure to US population.3. To examine the magnitude and distribution of procedures and doses from CT.
MO‐E‐352‐01: CR Mammography — What You Need to Know
Authors: Martin M 
Published: July 2008

The approval by the FDA of the Fuji FCRm in November 2006 allowed many facilities the opportunity to enter the era of Full‐Field digital imaging in mammography while utilizing their existing equipment previously using a film/screen imaging system. Although the mammography equipment producing the images spans the complete range of currently approved units from systems more than 10 years old to relatively new units, the image quality requirements for the Fuji FCRm system is independent of the equipment used to produce the images. The qualified medical physicist providing services to these facilities must be familiar with all aspects of the FCRm system to set up and oversee the Quality Control Requirements and to complete the required acceptance test procedures. This workshop will cover the required tests and evaluations of the FCRm system to be performed by the physicist covering the image producing equipment, the softcopy review workstations and the laser printer. Practical tips for performing these tests will be presented along with suggested worksheets.Educational Objectives:1. Attendees will know the Annual Tests required to be performed by the medical physicist to meet MQSA and ACR accreditation requirements.2. Attendees will be aware of methods to be used to perform the required tests of the Fuji FCRm system to meet accreditation requirements.3. Attendees will know the acceptable range of values required for each of the tests to be performed by the medical physicist to meet accreditation requirements and values to be used to establish the ongoing Quality Control program.
TU‐A‐AUD C‐01: Margins in Radiation Therapy
Authors: Low DA , Litzenberg DW 
Published: July 2008

Conformal radiation therapy has historically used margins to account for geometrical uncertainties in the position of a target volume. The margins, in their simplest form, are simply expansions to the shape of a treatment beam, to ensure that dosimetric planning criteria are met in the presence of inter‐ and intra‐fraction setup variations. Historically, the size of the margin in a given treatment site was difficult to determine due to the available technology and the time and effort required to obtaining accurate data. Consequently, margins were estimated to accommodate a population of patients. As new technologies have emerged, target volume position errors have become easier to measure, their accuracy has increased, and the measurements can be made much more frequently. As the quantity and quality of data has increased for patient populations, and even for individual patients, the conceptual basis of employing margins has evolved. Strategies for ensuring dosimetric coverage may now be individualized to a specific patient's geometric uncertainty characteristics with customized margins, or they may incorporate geometric correction based on predefined action levels. Other strategies may incorporate continuous monitoring to gate or modify the beam. And finally, other strategies seek to eliminate margins by including the estimated geometrical uncertainty into the development of the dose distribution.Educational Objectives:1. To provide an educational review of the technologies and methods of measuring target volume positioning errors.2. To review methods of determining population margins from measured data.3. To review corrective and intervention strategies for patients with individualized margins.4. To briefly review planning strategies which seek to eliminate margins.Conflict of Interest: DA Low: Research sponsored by Tomotherapy and Varian; DW Litzenberg: Research sponsored by Calypso Medical Technologies, Inc.
TU‐SAMS‐332‐02: Digital Mammography Detector QC, Tips and Problems
Authors: Berns E 
Published: July 2008

Digital mammography is quickly becoming the technology of choice for breast imaging with several FDA‐approved systems already available and more on the way. Digital detectors in mammography have different characteristics compared to the traditional screen‐film systems and require by the FDA different Quality Control tests. This lecture is going to discuss the practical issues for the medical physicist who wants to learn the differences in these Quality Control tests and how they impact the mammography facility and ACR accreditation. The lecture will be broken into several parts. The first will review currently available FFDM equipment and their respective Quality Control tests. The second part will compare similar QC tests and discuss the key differences. The third part will review quality control for review workstations and laser printers designed for digital mammography.Educational Objectives:1. To describe current quality control procedures for FFDM systems.2. To describe current quality control procedures for review workstations in digital mammography.3. To describe current quality control procedures for laser printers in digital mammography.4. To review the impact of QC on ACR accreditation for FFDM systems.
TU‐A‐342‐01: Quality Assurance Testing of Gamma Camera and SPECT Systems
Authors: Halama J 
Published: July 2008

Routine maintenance, calibration, and quality control of gamma camera and SPECT imaging systems is crucial for providing the nuclear physician or radiologist images of high quality without artifact. This lecture will provide an overview of the gamma camera and SPECT calibrations, performance measurements, and quality assurance tests, whether they are for routine quality control or annual physics surveys as defined by the ACR accreditation program. A discussion of common artifacts and how to avoid and correct them will be included.Gamma camera and SPECT performance measurements are well defined in documents published by MITA/NEMA and in AAPM Task Group reports. Unfortunately, many of the specified tests cannot be easily done on installed systems in the field. Modifications become necessary, and as a result performance measurements and quality assurance testing of gamma camera and SPECT systems have been quite variable. Not included in the published documents are calibration procedures that are vendor specific. Improper calibrations, particularly uniformity calibration, also lead to unwanted artifacts. It is the burden of the physicist to know which performance tests are critical in the field and to also become familiar with specific calibration procedures of our gamma camera and SPECT systems.Educational Objectives:1. Learn the basic gamma camera and SPECT performance measurements and quality assurance test procedures.2. Become familiar with calibration procedures of current systems.3. Become familiar with the test procedures and the frequency of testing prescribed by the ACR accreditation programs.4. Be able to identify common gamma camera and SPECT image artifacts and how to correct them.
TU‐B‐AUD C‐01: Deformable Image Registration: Methods and Clinical Endpoints
Authors: Kessler M 
Published: July 2008

Acquisition of anatomic and functional data from magnetic resonance imaging and nuclear medicine studies is becoming increasingly common for patient management in radiation therapy. These data can help improve tumor localization and normal tissue delineation for treatment planning and may provide information about treatment efficacy during or after a course of radiotherapy. Time series data from serial and 4D CT before and during the treatment course, including CT data acquired in the treatment room at the time of treatment, is also helping to estimate motion and shape changes of relevant anatomy. In order to fully realize the benefits of these data, the different imaging studies must be registered to each other or to a common coordinate system. The geometric transformation required to register the different image data can range from simple rotate‐translate to account for differences in patient orientation to 3D or 4D deformation models to account for changes in internal anatomy during and over the course of therapy. Once registered, data derived from the various studies such as anatomic outlines and computed dose can be integrated or fused to help construct a more complete and accurate representation of the patient.This lecture will focus on the mechanics of registering and displaying data from different imaging studies using distinct modalities or a single modality over time. A taxonomy of the different methods will be described. Methods for display and interaction with multimodality data will also be presented. The overall goal is to provide the basic knowledge required to understand what is happening “under‐the‐hood” of the different registration systems one might encounter in the clinic, the different ways these systems are being used for patient management and their limitations.Educational Objectives:1. Understand the basic mechanics of deformable image registration and data fusion techniques.2. Understand the tools used to combine, display & interact with multimodality/4D image and dose data.3. Understand the clinical use and limitations of these techniques for Tx planning, Tx delivery and plan adaptation.
TU‐C‐350‐03: Medical Physics Licensure Update
Authors: Limmer J 
Published: July 2008

To ensure that qualified individuals perform the job of clinical Medical Physics as outlined in the AAPM/ACMP Scope of practice. This is seen as important with or without the passage of the CARE Bill. The existence of the CARE Bill gives us the impetus to do this work. If we do not help the legislators define who is qualified to do our jobs, someone else will.In this session the activities of the Joint Medical Physics Licensure Subcommittee will be discussed. Topics will range from the rationale for the effort, the new full time position at HQ to help with the effort, the status of licensure efforts, and future goals and plans. In addition, the implications for the clinical practice of medical physics if it became law in more states will be explored.Educational Objectives:1. Be exposed to the rationale behind the effort for professional licensure.2. Understand what has been accomplished related to this effort.3. Hear what the near and long term goals are for the effort.
TU‐C‐AUD C‐02: CT Scanner‐Based IGRT
Authors: Graves E 
Published: July 2008

While small animal models of cancer have evolved to more closely resemble the corresponding human disease, radiation therapy (RT) techniques for small animals are dramatically different than those routinely used in the clinic. Recently there has been considerable interest in developing conformal radiotherapy methods for small animals so as to incorporate more clinically‐relevant treatment modalities into laboratory studies of cancer.An attractive approach to this engineering problem is to add radiotherapy capabilities to a micro‐computed tomography (microCT) scanner. This strategy exploits the high imaging performance of existing microCT units in order to produce a small animal image‐guided radiation therapy (IGRT) system employing a single X‐ray beam for imaging and treatment. If successful, this small animal IGRT option could be made available as an add‐on option to existing commercial microCT scanners, allowing widespread adoption of small animal conformal radiotherapy throughout the research community.Initial experiments demonstrated that the dose rate of a GE microCT system is suitable for delivering therapeutic radiation doses in reasonable treatment times. A variable aperture collimator capable of restricting the microCT X‐ray beam to a variable pseudo‐circular profile has been developed and evaluated. This prototype microCT/RT system is now online for experimental use, and is currently being applied towards a variety of biological studies.In this lecture I will briefly describe the current status and future work for this approach to small animal conformal radiotherapy. I will then discuss initial biological applications of this system, including treatment of orthotopic models of disease and evaluation of positron emission tomography (PET)‐guided radiotherapy strategies.Educational ObjectivesAt the end of this lecture, the audience will be able to:1. Describe the relative advantages and disadvantages of developing small animal radiotherapy within the context of existing microCT scanners.2. Identify biological applications of small animal IGRT where existing small animal irradiation techniques are inadequate, and3. Discuss the use of small animal IGRT as both a tool for small animal research and a method for conducting clinical trials in an experimental setting.
TU‐C‐AUD C‐04: Custom Built Small Animal IGRT Platform
Authors: Wong J , Armour E , Kazanzides P , Iordachita I , Ford E , McNutt T , Tryggestad E 
Published: July 2008

Over the past 2 decades, there has been a widening technological disparity between laboratory radiation research and clinical radiation therapy. Whereas simple single beam/single fraction techniques are commonly used to irradiate laboratory animals, advanced three‐dimensional (3D) and computer‐controlled delivery technologies are now used clinically to pinpoint fractionated conformal radiation therapy (CRT) and intensity modulated radiation therapy (IMRT). The technological disparity presents a difficult hurdle in the development of novel treatment methods that combine conformal irradiation and other therapeutic agents. There is clearly a pressing need to bridge the technological gap between laboratory radiation research and human treatment methods.To that end, we have constructed a Small Animal Radiation Research Platform (SARRP) which integrates imaging, radiation delivery and treatment planning capabilities. The SARRP spans 3 ft × 4 ft × 6 ft (W×L×H). A dual‐focal (0.4 mm and 3.0 mm) spot, constant voltage x‐ray source is mounted on isocentric gantry. The source to isocenter distance is 35 cm. Eighty to 100 kVp x‐rays from the smaller focal spot are used for imaging. Both focal spots operate at 225 kVp for irradiation. Robotic translate/rotate stages are used to position the animal. A novel configuration is devised for CBCT imaging by rotating the horizontal animal between the x‐ray source and a flat panel amorphous silicon detector that are fixed at opposite horizontal positions of 90° and 270° respectively. Radiation beams ranging from 0.5 mm in diameter to (60 × 60) mm2 are available. Conformal dose distributions are delivered using a combination of gantry and robotic stage motion. Treatment planning is performed at sub‐mm resolution where Monte Carlo dose calculations are coupled to a research Pinnacle system for visualization. Depending on filtration, the isocenter dose outputs at 1 cm depth in water range from 22 to 375 cGy/min from the smallest to the largest radiation fields. The 20% to 80% dose fall‐off spans 0.16 mm. CBCT with (0.55 × 0.55 × 0.55) mm3 voxel resolution is acquired with less than 1 cGy in 4 min. The ability of our system to focally irradiate a specific anatomic region or target in a mouse subject has generated exciting new collaborations between laboratory and translational research. These include the study of the response of normal tissue and tumor to focal radiation injuries; the development of molecular imaging markers for early assessment of radiation induced toxicity in the lungs; and the study of molecularly targeted therapy in combination with radiation. We are hopeful that our SARRP, and other similar initiatives, will serve to provide the timely and powerful technology to greatly transform future cancer treatment.Educational Objectives:1. Appreciate the disparity between animal radiation research methods and clinical treatment.2. Understand the challenges in down‐sizing human treatment methods for small animal.
TU‐C‐351‐06: Comparison of Multiple 3D‐3D Anatomy‐Based Rigid Image Registration Methods for Prostate Patient Setup Before External‐Beam Radiotherapy
Authors: Wu J , Murphy M 
Published: July 2008

Purpose: To assess the variability in translational setup corrections computed via several different 3D to 3D rigid registration methods and conditions using only the image intensity information. Method and Materials: Fifteen pairs of male pelvic CTs were rigidly registered using multiple registration metrics, methods, and image content. Similarity was measured using mutual information and mean‐squared‐difference. The registrations were iterated using two different search algorithms. The effect of image resolution was observed by downsampling in each slice by factors of 2 and 4. The effects of image content were observed by using the entire image and then using only bony landmarks in the similarity measures. The uncertainty associated with the choice of source and target images was revealed by switching the roles of the two registered images. For each image pair the translational shifts for all the registration methods and conditions were compiled and the standard deviation around the mean shifts was computed. Results: Reversibility errors ranged from 0 to 1.8 mm for the various algorithms and conditions. The radial standard deviation of the various methods and conditions was 0.8 mm when the entire image was registered and 0.3 mm when only bony landmarks were used. Downsampling by a factor of 2 improved robustness with only a small loss in precision. Mutual information failed in nearly all cases when the images were thresholded to isolate bony features. Conclusion: Rigid image registrations have an intrinsic uncertainty that depends on the algorithm, the resolution of the images, and the features used to establish rigid congruence. Registration uncertainty should be accounted for in planning margins and patient setup procedures. In the absence of an absolute ground truth test of registration accuracy, the standard deviation in the shifts calculated by several different methods provides a useful estimate of that uncertainty.Supported in part by NIH P01CA116602.