bluuebunny/crossref_metadata_2025_split huggingface dataset:
MO‐E‐224A‐01: Stereotactic Body Radiation Therapy: (1) Clinical Outcomes Following SBRT IGRT
Authors: Dawson L 
Published: July 2006

Advances in high precision radiation planning and delivery, image guidance technologies and methods to account for and reduce organ motion have made it possible for cranial stereotactic radiosurgery techniques to be applied to tumors outside of the brain. Stereotactic body radiation therapy (SBRT) refers to the use of a limited number of high dose fractions delivered very conformally to targets with high accuracy, using biologic doses of radiation far higher than those used in standard fractionation.The rationale for SBRT is that there is a need for improved local therapies for many primary cancers and also in the situation when there are ‘oligo’ (i.e. isolated) metastases, specifically in sites where surgery has been shown previously to be able to cure patients with ‘oligo’ metastases, e.g. colorectal cancer, renal cell cancer and sarcoma. SBRT has the potential to be used in place of surgery in situations when surgery may associated with high risk.Advancements outside of radiation oncology also provide rationale for SBRT. Functional imaging such as PET allows better patient selection for SBRT. Furthermore, improvements in systemic therapy more likely to control micro‐metastases provide rationale for improving local therapies, such as SBRT, to reduce large foci of tumor burden.There are radiobiological advantages to SBRT including less opportunity for tumor repopulation and repair. Furthermore, the shorter SBRT treatment times are more convenient for patients and have resource utilization advantages.With highly potent doses of SBRT delivered with steep dose gradients, the potential for geometric uncertainties in the setting of SBRT to lead to adverse clinical outcomes (tumor recurrence and/or toxicity) is high. Thus, the need for image guided radiation therapy (IGRT) to improve precision of dose delivered is heightened. IGRT decreases the heterogeneity in delivered doses, improving our ability to measure the impact of dosimetric and non‐dosimetric factors on SBRT clinical outcomes.This lecture will provide an overview of the rapidly increasing clinical experience with SBRT and IGRT in the setting of SBRT. Case examples demonstrating clinical benefits and potential toxicities will be discussed.Educational Objectives:1. To understand the clinical rationale for SBRT.2. To describe the rationale for IGRT in SBRT.3. To understand the increased risks of SBRT compared to conventional RT and the increased potential for error.
MO‐E‐230C‐00: Display Evaluation Demonstration Workshop: Part II
Authors: Samei E 
Published: July 2006

Participants:J Charette, Barcoview, LLC;E Samei, Duke University;N Hashimoto, Eizo Nanao;K Compton, National Display Systems;A Abileah, Planar Systems;D Sorensen, Richardson Electronics / Image Systems;C Lipfert, Scanditronix Wellhofer GmbH;M Hasegawa, Totoku;H Roehrig, University of Arizona GmbH; M Hasegawa, Totoku; H Roehrig, University of ArizonaElectronic display is a key component of modern medicine, providing soft‐copy viewing of medical images. Being the last component of the image chain, display quality can have a notable impact on overall accuracy and efficiency of the diagnostic process. Thus, it is necessary to ensure that the physical performance of a medical display is adequate for its intended use. Led by a task group initiative by the American Association of Physicists in Medicine (AAPM TG18), new guidelines have recently been published defining objective and standardized assessment procedures and criteria for acceptance testing and quality control of medical display devices (Samei et al, Med Phys 32:1205–25, 2005). The guidelines include detailed visual and quantitative methods and specific acceptance criteria for basic display characteristics including luminance, luminance spatial and angular response, resolution, noise, veiling glare, reflection, color uniformity, geometrical distortions, and display artifacts. The TG18 guidelines are also being gradually reflected in a number of other national and international directives including those by the IEC and the ACR. The goal of this demonstration workshop is multi‐fold: 1) to present a tutorial on the TG18 guidelines and its adaptations, 2) to discuss its implementation by specific vendors, 3) to offer an opportunity for hands‐on exposure to the practical aspects of display performance evaluation, 4) to provide an opportunity to informally interact with experts and ask questions, and 5) to offer a panel discussion on the issues about which there might be less consensus among experts. Representatives from the TG18 committee and from industry will be present to demonstrate and discuss display evaluation issues.Part II:4:00–4:10 Local and Remote QA/QC for Color Monitors, H Roehrig, Univ of Arizona4:10–4:20 QA Luminance Measurements at Medical Displays using a Flexible Spot Luminance Meter, C Lipfert, Scanditronix Wellhofer GmbH4:20–5:10 Hands‐on demonstration:5:10–5:30 Plenary Q&A and panel discussion
MO‐E‐230C‐01: Local and Remote QA/QC for Color Monitors
Authors: Roehrig H 
Published: July 2006

The adoption of digital detectors and PACS has provided physicians in healthcare institutions with an effective means to electronically generate, transmit, archive, retrieve and display images to be used for the diagnosis of disease. Monochrome CRTs and LCDs were the original choice of displays. Now color displays are increasingly replacing monochrome displays mainly for cost reasons in Radiology, but also for use in multi‐modality display stations and in areas where color is essential such as in Telemedicine and Telepathology.The ACR‐NEMA Working Group 11 has developed a Display Function Standard to allow for the standardization of monochrome image display devices. The AAPM Task Group 18 has developed methods to permit implementation of image Quality Assurance Programs as well as Acceptance Procedures for monochrome display devices.No Display Function Standard is available for the standardization of color display devices nor are there recommendations for image Quality Assurance Programs or Acceptance Procedures for color display devices.This presentation demonstrates that consistent color presentation as well as consistent grayscale presentation for digital color displays can be achieved with the appropriate software and a simple and portable color detector. The software to achieve color fidelity works fast and, with the aid of the portable detector, can be applied remotely, saving precious resources in the management and operation of color displays.The presentation also provides a look into the future when a handheld color camera will be available to permit in‐field evaluation of pertinent image quality measures like modulation transfer function and signal‐to‐noise ratio of color display devices in the reading room.
TU‐A‐ValA‐01: DICOM: What the Physicist Needs to Know
Authors: Junck K 
Published: July 2006

The DICOM (Digital Imaging and Communications in Medicine) standard has allowed for tremendous changes to occur in the workflow of a modern radiology department. Prior to DICOM, radiological images were generated, transmitted, and stored in proprietary formats by imaging vendors. DICOM provides a standard to define objects such as images and services that may be performed upon those objects. As with any disruptive technology, it has solved some problems and created a whole host of new issues. Some of these issues are being addressed within the DICOM standard while others have taken on a new life under the auspices of IHE (Integrating the Healthcare Enterprise). IHE is an initiative by healthcare professionals and industry to improve the way computer systems in healthcare share information.This lecture is intended to provide an overview of the DICOM “language” and look at some current DICOM issues at our institution.Educational Objectives:1. Review the history of the DICOM standard and understand its origins and goals.2. Understand the language of DICOM objects and services.3. Understand the possible sources of DICOM issues.4. Learn of available online resources for additional information.
TU‐A‐224A‐01: Positron Emission Tomography for Oncologic Imaging and Treatment
Authors: Bourland J 
Published: July 2006

Purpose: Positron Emission Tomography (PET) images show physiological and biological information through the in‐vivo distribution of radioactive, short‐lived, positron‐emitting species. PET imaging shows focal and distributed regions of cancer and its metastases. PET uses in oncology include diagnosis, staging, and disease monitoring, important for prognosis and treatment decisions. Quantitative uses of PET include assessment of the degree of malignancy and target definition for radiation treatment. Hybrid PET‐CT devices are being used as radiation treatment simulators. Method and Materials: F‐18‐labled Fluoro‐deoxyglucose (F‐18 FDG) is the most commonly used PET imaging agent. FDG shows regions of active glucose metabolism, such as local cancer, metastases, non‐cancer inflammation, and normal glucose use in brain. Non‐FDG PET agents can be highly specific in tissue targeting (binding), such as F‐18 Misonidazole and C‐11‐labeled amino acids, to image tumor biology like hypoxia and cell proliferation, respectively. Results: PET imaging has coarse spatial resolution compared to CT and MR. PET's clinical use is valued because of its great sensitivity for cancer detection. Voxel intensity and image fidelity depend on equipment design, patient size, anatomic site, and imaging study parameters. PET‐CT units enable CT‐based attenuation corrections and inclusion of CT information in a registered PET‐CT dataset. Interest is high for PET‐CT simulators. The Standardized Uptake Value (SUV) is a normalized intensity measure for quantitative indication of disease, and can be used for target delineation, with certain constraints. Conclusion: This course reviews the basic physics of PET, uses of FDG and non‐FDG PET for oncology imaging, and quantitative aspects for PET‐based radiation target definition. Example images demonstrate the potential contributions and limitations of FDG and non‐FDG PET oncology imaging. This review course is intended for both imaging and radiation oncology physicists.Educational Objectives:1. Review the basics physics of PET imaging.2. Describe FDG PET imaging and oncologic indications.3. Review the uses and limitations of PET images in radiation treatment.4. Describe the SUV and other threshold parameters for target delineation.5. Review non‐FDG PET imaging of tumor biology.Conflict of Interest: Research sponsored in part by Varian Medical Systems and GE Healthcare.
TU‐A‐224C‐01: Daily Localization II: EPID, MVCBCT
Authors: Pouliot J 
Published: July 2006

The Mega‐Voltage Cone‐Beam CT (MVCBCT) system provides a 3D image of the patient anatomy in the actual treatment position that can be tightly aligned to the planning CT, allowing daily verification and correction of the patient position moments before the dose delivery. Integrated onto a linear accelerator, the system consists of a new a‐Si flat panel adapted for MV imaging and a workflow application allowing the automatic acquisition of projection images at low dose rate, CBCT image reconstruction, CT to CBCT image registration and couch position adjustment. Moreover, MVCBCT provides accurate electron density and allows studies of dosimetrical impact of setup error, anatomical changes or presence of implanted metallic objects.This lecture will provide an overview of the physics characteristics of MV and MV CBCT imaging, acceptance testing and commissioning, acquisition and reconstruction, image registration, alignment precision and quality assurance procedures. An overview of the clinical applications will be provided. Finally, current challenges and future developments will be addressed.Educational Objectives:1. Understand the basics concepts of MV Cone‐Beam CT imaging.2. Understand the workflow and issues related to clinical applications of MV CBCT, including acquisition, reconstruction, registration and patient alignment.3. Understand the possibilities of 3D Imaging for patient alignment.This work was supported by Siemens Oncology Care Systems.
TU‐B‐330D‐01: Design and Performance Characteristics of Flat‐Panel Acquisition Technologies
Authors: Yorkston J 
Published: July 2006

Flat‐panel detectors are becoming more commonplace throughout the world for numerous applications ranging from mammography to megavoltage imaging and from static projection radiography to real‐time fluoroscopy and cone beam CT. A detailed understanding of their advantages and limitations is essential to ensure their efficient integration into the clinical environment. This presentation will review their place in the current DR detector landscape and the unique features that provide them with their improved image quality performance when compared to other approaches. The differences and similarities between the various flat‐panel designs will also be discussed with a view to highlighting their inherent image quality capabilities as well as some practical limitations to their performance. The process of gain/offset corrections will be reviewed and the issue of bad pixels, defective lines and image artifacts commented on. The implications of certain gain calibration procedures will be reviewed in terms of the possibility of image artifact creation, in particular in terms of other system components such as anti‐scatter grids and AEC circuitry. The impact of non‐linear behavior and pixel saturation will also be reviewed. In conclusion the development of advanced imaging applications such as dual energy, tomosynthesis and cone‐beam CT will be reviewed.Conflict of Interest: John Yorkston is an employee of Eastman Kodak Company which sells DR systems based on CsI(Tl) type Flat‐Panel detectors.Educational Objectives:1. Review the range of DR and flat‐panel detectors currently available and their design and performance differences.2. Review the process of gain/offset calibration and its benefits and limitations.3. Review the impact of pixel and line defects, correlated line noise, pixel saturation and other characteristics behaviors of flat‐panel detectors.4. Review the prospect of advanced applications utilizing flat‐panel technology.
TU‐B‐ValA‐01: Digital Fluoroscopic Imaging: Acquisition, Processing and Display
Authors: Belanger B 
Published: July 2006

The modern digital fluoroscopic imaging system has evolved to levels of complexity and automation that, when properly applied, can provide enhanced clinical performance and flexibility over a wide range of clinical applications in a user‐friendly manner. However, achieving maximum performance from such complex systems may be best achieved through cooperative efforts between manufacturers and clinical users, in which the well‐informed clinical team can utilize the degrees of freedom available in these systems to achieve the best clinical results for each medical application of interest. The medical physicist plays an important role in this process as the person who understands the relationships between physical imaging parameters, dose, and clinical imaging performance. Therefore, an understanding of system architectures, design philosophies, image processing capabilities, and degrees of freedom in procedure programming allow the medical physicist to play a more effective role. To this end, an overview of modern digital fluoroscopic imaging system will be presented, with particular attention given to the range of fluoroscopic and record imaging modes provided, automatic exposure control systems, common image processing algorithms, and procedure protocol selections. Recommendations for minimizing pitfalls in equipment testing will also be presented, along with some of the unique considerations for flat panel detectors versus image intensifier‐based imaging systems.Research sponsored by GE Healthcare.Educational Objectives:1. Understand the architecture of modern fluoroscopic systems, including major image and data communication pathways, control systems, and image processing from acquisition to display.2. Gain familiarity with the flexibility in control and processing afforded by new technologies and architectures, and how manufacturers use these.3. Be aware of the various fluoroscopic imaging modes and the related image quality and dose considerations, including dose monitoring and reporting.4. Understand common image processing techniques, such as edge enhancement, multiband filtering, and temporal filtering, and their impact on image quality.5. Recognize the unique aspects of Digital Flat Panel Detectors and the related implications for fluoroscopic system behavior and performance.6. Be able to identify the types of automation implemented in systems, and know how to avoid related pitfalls in testing.7. Recognize the various procedure protocol programming capabilities available, and how they may be customized to meet clinical objectives.
TU‐C‐330D‐01: Advances in Breast Imaging
Authors: Shaw C 
Published: July 2006

Despite development and advances of new modalities, x‐ray mammography remains the main screening tool for early detection of breast cancers. It also continues to play an important role in the diagnosis and management of breast cancers. X‐ray mammography has relied on the use of high resolution screen/film combinations. Such techniques, although improved over the years, have the drawbacks of all the inconveniences and inflexibility associated with the use of film for image acquisition, storage and display. Motivated by search for better image quality and a general move towards filmless radiology, various digital mammography techniques have been developed, investigated and commercialized. These techniques can be largely divided into four types: amorphous silicon and selenium flat panel detector, amorphous silicon and cesium iodide flat panel detector, CCD and cesium iodide based slot scanning system, and storage phosphor imaging technique with dual‐side image read out. Each of these systems has its unique advantages and disadvantages and achieves various degrees of clinical implementation. Typical of all digital mammography techniques is the potential compatibility with digital image archival, retrieval and distribution systems. Furthermore, the acquisition of breast images in digital format has begun to facilitate the development and investigation of many advanced imaging techniques. Among them, dual‐energy mammography techniques have been developed to quantify breast tissue composition or to separate calcifications from the overlying tissue structures. Stereo‐mammography has been developed to use two projection views to provide a 3‐D perspective of the breast tissue structures, thus reducing the problem of overlapping structures. Tomosynthesis imaging pushes the idea of 3‐D imaging further by acquiring 10–25 projection views and use them to synthesize images to depict the breast structures as a number of thick layers. More recently, cone beam breast CT has been developed and investigated to scan the breast in a dedicated manner and provide true 3‐D images of the breast. Along a different direction, the development and investigation of various contrast mammography techniques have allowed x‐ray imaging to be used to image and study breast vasculatures as possible indication of breast cancer.In this presentation, we will try to achieve the following educational objectives:1. Review the development and investigation of major digital mammography techniques.2. Review the development and investigation of various advanced breast x‐ray imaging techniques.Research sponsored by the National Cancer Institute and the National Institute of Biomedical Imaging and Bioengineering.
TU‐C‐ValA‐03: Concurrent Multimodality Image Segmentation
Authors: El Naqa I , Bae K , Zheng J , Khullar D , Bradley J , Grigsby P , Low D , Deasy J 
Published: July 2006

Purpose: Generally, in MRI, PET, and CT image datasets, more information is available for defining the target volume (or normal structures) than is used during the target segmentation. We introduce a method to take advantage of all the imaging information available for target segmentation, including multi‐modality images or multiple image sets from the same modality. Method and Materials: We generalized the multi‐valued level set deformable model (Chan et al., JVCI (2000) 11:130–141) for simultaneous 2D/3D segmentation/registration of multi‐modality images consisting of a combination of PET, CT, or MR datasets. Information from multi modality image sets is combined to define the final target volume. The method was evaluated on three patient cases, including: a non‐small cell lung cancer case with PET/CT, a cervix cancer case with PET/CT, and a prostate patient case with CT and MR. Results: In the case of the lung tumor the level set algorithm took 120 iterations for convergence, while in the case cervix tumor it converged after 30 iterations because the tumor has a deformed circular shape. In the prostate case, it took 50 iterations to converge and the results were made more sensitive to the shape prior information, because MR provides less gradient strength than PET. The computational time was on the order of few seconds in all cases. Conclusion: We a developed a new target segmentation algorithm which uses information simultaneously from multiple modalities. Our initial results indicate that the algorithm is promising and could provide physicians with a reliable contouring tool for lung, cervical, and prostate cancer.This research was partially supported by NIH grant R01 CA85181 and a grant from TomoTherapy, Inc.
TU‐C‐ValB‐04: Margin‐Less Prostate IMRT Plans, Directly Optimized for TCP and NTCP Including Geometric Uncertainties
Authors: Witte M , van der Geer J , Schneider C , Lebesque J , Alber M , van Herk M 
Published: July 2006

Purpose: To account for geometric uncertainties without the use of margins during IMRT planning such that optimal values are obtained for the population averaged TCP and NTCP functions. Methods and materials: A new method of computing cost functions was implemented within the IMRT planning tool Hyperion. Population‐averaged values of biologic score functions (TCPpop and NTCPpop) are optimized, simulating random errors by blurring the dose, and systematic errors by displacing target and OARs relative to the dose distribution.For 19 prostate (and seminal vesicle) patients, treatment plans for a five beam setup were created, optimising TCPpop while constraining rectum NTCPpop and the maximum dose to the target. Gaussian distributions were used for the systematic and random errors (translations only, no attempt was made to model rotations or deformations). Since geometric uncertainties were accounted for within the cost functions, no CTV to PTV margin was used. For comparison, conventional plans were created using a CTV‐to‐PTV margin (M=2.5Σ+0.7σ) and a Simultaneous Integrated Boost (SIB) technique (68Gy to the above PTV, 78Gy to PTVboost with 5mm margin, 0mm towards rectum). The resulting plans were evaluated using an independent tool that simulates the effects of geometric uncertainties. Results: Compared to conventional plans, our new technique reduced the planned dose to the rectum, while increasing the volume receiving 78Gy. We ensured that TCPpop of the new technique was not smaller than for conventional techniques. The average rectum NTCPpop values were 14% (margin recipe), 8% (SIB), and 4% (new technique), for average TCPpop values of 69%, 70%, and 71%. Conclusions: The computation of TCP and NTCP including knowledge of geometric uncertainties within the inverse IMRT optimization loop is feasible (less than 1 hour optimization time), and results in robust prostate treatment plans with an improved balance between local control and rectum toxicity.