bluuebunny/crossref_metadata_2025_split huggingface dataset:
MO‐A‐303A‐01: MR Acceptance Testing and Quality Control: Report of AAPM MR Subcommittee TG1
Authors: Jackson E 
Published: April 2010

The MR Subcommittee of the AAPM Imaging Physics Committee (IPC) has recently completed a revision of the previous AAPM TG1 and TG6 reports on MR acceptance testing and quality assurance. The report of the MR Subcommittee has been approved by the IPC and will be available electronically (http://www.aapm.org/pubs/reports/). In this session of the MR continuing education course, the contents of the report will be presented. Recommendations regarding testing of magnetic and radiofrequency (RF) shielding will be followed by recommendations on specific acceptance tests of magnetic field homogeneity, the RF subsystem (calibration, stability), the gradient subsystem (calibration, eddy current compensation), combined subsystems (slice thickness and spacing), global system performance (SNR, uniformity, high and low contrast resolution), and advanced tests (MR spectroscopy, echo planar imaging).Objectives:1. Understand the requirements for MR site and system acceptance tests.2. Review recommended MR site and system acceptance testing procedures, including phantom selection, data acquisition, data analysis, and reporting.3. Review recommended action criteria for both standard imaging options and advanced imaging and spectroscopy options.
MO‐B‐210A‐01: Digital Dose Reporting
Authors: Balter S 
Published: April 2010

This course will review the availability of digital radiation dose reporting tools An increasing fraction of imaging equipment is capable of measuring its own X‐ray output. Dose and related information is present in many DICOM image headers. Depending on the make/model/software data is in some mix of public and private fields. This information usually reports only the dose associated with the images in the file.DICOM now provides tools for communicating dosimetric and related data in a comprehensive manner. A first‐generation structured report (RDSR), optimized for fluoroscopically guided procedures, was released as part of the 2007 DICOM Standard. Similar structures for mammography and computed tomography are in the 2008 Standard. The RDSR is a DICOM object that is created and managed separately from the creation and storage of images. Even if images are discarded (e.g. fluoroscopy, rejected radiographs), the RDSR will record all of the radiation used during a procedure.All of the data in a RDSR is in public fields, each identified by a DICOM tag or unique concept name. The RDSR always contains patient and examination data, total dose data for the entire procedure. For interventional procedures, the RDSR also contains technical, geometric, and dosimetric data for each individual irradiation. RDSRs are designed to be distributed on a network and captured by free‐standing dose‐management ACTORS as well as by RIS and PACS. The IHE Radiation Exposure Monitoring (REM) Profile gives additional guidance and supplies use cases for RDSR handling. In addition RDSRs can also be stored within an imaging system and manually downloaded.Learning Objectives1. Understand the availability of dose information in DICOM image headers.2. Understand the functionality of the new DICOM RDSR and associated components.3. Understand how to use the RDSR and other dose reporting tools as part of an institutional quality program.
MO‐B‐213A‐01: Magnitude of Radiation Exposure to US Population (NCRP Report ♯160) with Focus On CT Dose
Authors: Mahesh M 
Published: April 2010

National Council of Radiation of Protection (NCRP) recently released a long awaiting report (NCRP report ♯ 160) on the radiation exposure of the US population from various sources including medical exposure. This new report replaces the current NCRP report ♯ 93 published in 1987.According to the newly released NCRP report ♯ 160 (March 2009), the medical radiation exposure to US population has increased by nearly 6 times compared to the previous NCRP publication (NCRP 93). The previous pie‐chart published in 1987 (NCRP report ♯93) indicated contribution of 3 mSv from background radiation, 0.53 mSv from medical exposure and 0.07 mSv from other sources (consumer products, occupational and other sources) exposure while the new pie‐chart published in March 2009 (NCRP report ♯160) indicates contribution of 3.1 mSv from background radiation and 3.0 mSv from medical and 0.1 mSv from all other sources (consumer products, occupational and other sources).The largest contributor to the collective dose to US population is from CT and Nuclear Medicine. CT scanning has increased nearly 10–11% annually in the US in the past two decade. The number of CT procedures has increased from 3 million CT scans in 1980 to more than 69 million CT scans in 2007.The purpose of this talk is to provide an overview of the newly released NCRP report ♯160. As a member of the NCRP scientific committee 6‐2 that developed the above report, the author will also focus on the medical radiation exposure including CT.Learning Objectives:1. To become familiar with the NCRP report number 160.2. To learn about the various sources and magnitude of radiation exposure including medical radiation exposure to US population3. To familiarize with the types and distribution of medical imaging procedures in US.4. To examine the various aspects related to CT use and CT dose.
MO‐D‐BRC‐02: Clinical Significance of In‐Vivo Proton Range Detection and Potential of MRI Scanning After Proton Therapy
Authors: Hong T 
Published: April 2010

Highly conformal radiation therapy has the potential advantage of limiting radiation exposure to normal tissue and improving the therapeutic ratio of radiation therapy. However, with improving technologies, much greater emphasis has been placed on the accuracy of both treatment delivery and localization. Shrinking PTV margins based on our confidence in the perceived accuracy of our treatment delivery runs the risk of geographic miss and subsequent marginal recurrences. Proton therapy is particularly prone to this risk. Range uncertainties exist at the distal edge of the Bragg peak. Also, proton range and depth of penetration is highly dependent on tissue density. Hence, for moving targets with changing densities within the field, like at the lung bases or dome of the liver, there is greater uncertainty in the dose that was actually delivered to the tumor and normal tissue. For these reasons, verification of dose delivered in patients receiving proton therapy is of critical importance.Post‐treatment imaging may be a useful way to verify proton range in‐vivo. Radiation may produce changes in imaging characteristics within organs that may be used to verify that the target has been adequately treated. In this lecture we will review some of the issues that complicate proton planning. Furthermore, we will demonstrate the utility of MRI scanning after proton therapy to document target coverage for both static and dynamic tumor systems.Learning Objectives:1. Discuss the clinical data regarding marginal misses with highly conformal therapy2. Demonstrate the complexities of 4‐dimensional proton planning for moving targets, using liver as a model3. Demonstrate the utility of post‐treatment MRI scanning as validation of the 4D‐proton treatment planning process and delivery for liver, as well as other clinical situations.
MO‐D‐304A‐04: Cone‐Beam CT Lag Correction Models: Effect of Optimized Parameter Selection
Authors: Mail N , Moseley D , Siewerdsen J , Jaffray D 
Published: April 2010

Purpose: Image lag degrades image quality in cone‐beam CT (CBCT). This work investigates the magnitude of lag artifacts and develops an optimized lag coefficient model to correct lag artifacts in CBCT images to improve guidance of radiotherapy(Elekta Synergy XVI). Method and Materials: Image lag and its relationship with various parameters including signal strength and frame number was investigated for a PerkinElmer (RID1640) flat‐panel imager. A new lag correction model referred to as the “average‐optimized lag coefficients model” (ALCM) is developed to correct CBCT images. The optimization of lag coefficients was purely based on quantitative improvement in lag corrected CBCT images. Each projection was corrected for lag effects by subtracting previous projections weighted by the magnitude of image lag. The quantification/measurement of lag coefficients for four different techniques including RESF(Rising‐Edge‐Step‐Response‐Function), IRF(Impulse‐Response‐Function), FESF(Rising‐Edge‐Step‐Response‐Function) and ALCM(Average‐Optimized‐Lag‐Coefficient‐Model) for the same detector. These models are applied/tested in correcting CBCT images of two customs made phantoms referred to as Ellipse_Lucite (MTF and skinline) and Irregular_Lucite (CNR). Results: Experimental results illustrate that the nth frame lag of the imager for all four model shows different behavior with frame number. The RCTN at 5 mm depth after lag correction was measured in CT♯ as 4.38±1.01, 10.51±1.35, 8.35±1.31 and 2.121±0.81 for RESF, IRF, FESF and ALCM, respectively. Similarly, the spatial frequency/cm for MTF(50%) before and after lag correction for RESF, IRF, FESF and ALCM was measured as 6.3±0.24, 5.7±0.23, 5.8±0.22 and 6.5±0.24, respectively. CNR for ALCMwas almost two times higher than nominal. Conclusion: Lag artifacts can be reduced by correction of the projection images using the ALCM model. Lag correction is most important for high contrast and irregularly shaped objects. The performance metrics suggest a significant improvement for RESF and ALCM and strongly support their use for lag correction in cone‐beam CT.Research sponsored by Elekta.
MO‐D‐213A‐01: ACR Accreditation
Authors: MacFarlane Carolyn R 
Published: April 2010

The American College of Radiology's (ACR) Nuclear Medicine and PET Accreditation Programs evaluate qualifications of personnel, equipment, image quality, and quality control measures. It is believed that these are primary factors that impact the quality of patient imaging. The ACR accreditation allows facilities to critique and improve their practices as part of their preparation for the accreditation evaluation process. The goals of the ACR Nuclear Medicine and PET Accreditation Programs are improvement in the quality of imaging, provision of educational information by raising awareness of imaging issues, and the recognition of imaging facilities which meet program objectives. This presentation will outline the program requirements, highlighting some of the common pitfalls that may cause deficiencies in both the clinical and phantom submissions.This presentation will provide participants with:1. General information describing the ACR Accreditation Programs2. Information about the Diagnostic Modality Accreditation Programs3. Specific information about the ACR Nuclear Medicine and PET Accreditation Program, to include the application process, clinical images submission and quality control requirements.
MO‐EE‐A3‐04: Motion Management for a Novel Ophthalmic Stereotactic Radiosurgical Device
Authors: Chell E , Arnoldussen M 
Published: April 2010

Purpose: Teletherapy of an unconstrained eye poses risks because of the likelihood of substantial eye motion. A new 100kVp tabletop stereotactic radiosurgical unit has recently been developed to deliver highly‐collimated beams of x‐rays to the retina. Here we evaluate the efficacy of a hardware and software motion‐management solution designed for that system. Method and Materials: To minimize the effects of motion during therapy, an eye fixation device (the “I‐Guide”) was developed. It consists of a contact‐lens, a central post, and a fixed, horizontal stabilizer bar. The contact lens is held to the eye with suction and attached to the central post. The post is mounted to stabilizer bar via a ball‐joint. The I‐Guide steadies the eye and incorporates reflective fiducials that are used by an imaging system to monitor the position and gaze‐angle of the eye. During treatment, software continuously evaluates the deviation of the eye from nominal position. When necessary, the beam is automatically gated off by an algorithm that incorporates time as well as displacement, allowing brief excursions while still maintaining effective targeting. Results: The motion‐management system was evaluated in a clinical trial of 40 patients. With the I‐Guide in place, rapid eye motion was damped considerably. Because of the time component, the gating algorithm permitted brief, random excursions while stopping the beam when excess drift was apparent. With a 3‐second x‐ray source ramp‐up, this flexibility was important for efficient treatment flow. Although patients' heads were immobilized, head mobility was found to be the dominant source of motion. However, the automatic gating‐off of the beam followed by repositioning kept the average motion error under 0.4mm in all cases. Conclusion: The combination of I‐Guide fixation, fiducial tracking, and automated beam gating enables precise targeting and dose conformality for ophthalmic radiotherapy.Research sponsored by Oraya Therapeutics
MO‐E‐213A‐03: The Cancer Biomedical Informatics Grid — A Tremendous Resource for Research and Clinical Care
Authors: Siegel E 
Published: April 2010

The cancer Biomedical Imaging Workspace is a part of the National Cancer Institute's caBIG initiative which is an effort to utilize grid computing and well defined standards to create a semantic web for exchange of research and clinical information including proteomic, genomic, laboratory, clinical, and imaging data. The Imaging Workspace consists of experts from the diagnostic imaging and radiology oncology communities across the United States with a wide variety of different areas of expertise. The purpose of the workspace is to identify and address challenges in the exchange and cross‐correlation of images and related information including image visualization and processing and analysis algorithms for research and secondarily clinical applications. The current major projects of the workspace include an effort to create a standard for annotation and image markup (AIM), a set of tools to facilitate the creation of applications that utilize the DICOM working group 23 standard (application hosting), middleware to create software bridges between DICOM and grid computing protocols and an algorithm validation toolkit which represents a resource for validation of a wide variety of imaging algorithms. The NCI has also created a free and open source DICOM image archive designed as a research repository for clinical trials that can also be used for a variety of other purposes. The Vasari Project represents a project which integrates the imaging workspace tools and is designed to allow correlation of MRI studies in patients with brain tumors with genomic and clinical data in a demonstration project of the potential role of diagnostic imaging in personalized or stratified medicine.Learning Objectives1. Understand the goals and objectives of the NCI's caBIG imaging workspace2. Be able to list the major projects of the imaging workspace3. Describe how the Vasari project will integrate the workspace projects in an initiative to allow cross correlation of image data with associated genomic, laboratory, and clinical data
TU‐B‐210A‐01: Quality Assurance Testing of Gamma Camera and SPECT Systems
Authors: White S 
Published: April 2010

Routine quality control, calibration and performance testing of gamma cameras are necessary in order to consistently acquire good quality images without artifacts. This lecture will briefly cover the basics of gamma camera image formation and performance characteristics. The lecture will primarily focus on quality assurance tests for gamma cameras, both routine quality control and annual physics surveys. Some of the performance tests proscribed by NEMA are difficult to perform in the field so the physicist needs to know which tests are critical and practical ways to perform them in the field.It is becoming increasingly common for providers of nuclear medicine imaging services to seek accreditation, either from the American College of Radiology (ACR) or the Intersocietal Commission for Accreditation of Nuclear Medicine Laboratories (ICANL). The ACR defines a set of performance tests for the annual physics survey and these will be discussed as well as the tests required for submission for accreditation.Common problems and image artifacts will be discussed as well as how to correct these problems. Calibration procedures such as center of rotation and uniformity calibration will be discussed.Learning Objectives:1. Learn the basics of gamma camera and SPECT performance measurements and quality assurance test procedures.2. Become familiar with the annual physics survey performance tests defined by the ACR accreditation program.3. Be able to identify and correct common problems and image artifacts in gamma camera and SPECT imaging.
TU‐C‐BRD‐06: Preclinical Image Guided Microirradiators: Concepts, Design and Implementation
Authors: Izaguirre EW , Kassebaum BL , Birch J , Su I , Mutic S , Parikh P , Grigsby P , Low D 
Published: April 2010

We will introduce small animal image guided microirradiators by reviewing the concepts and requirements for high resolution and high conformality irradiation of tumors implanted in small animal limbs (xenograft tumor models), animal organs and spontaneous tumor models. We will present two preclinical microirradiators developed by our group, a brachytherapy based microirradiator and an orthovoltage x‐ray source based microirradiator. The brachytherapy irradiator has been constructed around a commercial high‐dose rate (HDR) remote afterloader source in a teletherapy geometry. The system consists of a set of exchangeable tungsten collimators (from 2.5 to 5.5 mm diameter) mounted on an aluminum cylindrical support. An HDR catheter is then used to transport the source to the pre‐determined dwell position that centers the source at the collimator hole. With this microirradiator, the anatomical image is obtained using an external clinical CT operated at maximum resolution and coregistration is achieved using fiducial markers.The x‐ray orthovoltage microirradiator has an onboard cone beam microCT subsystem for submillimeter low dose anatomical imaging. The microCT and the ontrovoltage x‐ray source are aligned using a common rotation axis in a tandem configuration. An axial motorized animal bed transfers the animal from the microCT subsystem to the microirradiation subsystem. The microCT subsystem was constructed using an 80 kVp micro‐focus x‐ray source with a 75 × 75 um2 focal spot and a flat panel amorphous silicon detector with 1024 × 1024 pixels. The orthovoltage irradiator subsystem was constructed using a 320 kVp x‐ray source with dual focus spots (0.4 × 0.4 mm2 at 800W and 1 × 1 mm2 at 1800 W). The orthovoltage beam is collimated using orthogonal jaws and exchangeable apertures. The treatment beam can be aimed at different latitudinal and longitudinal angles in steps of 2 arcmin. and translated at 100 μm steps (x, y and z). The beam cross sections can be modulated with submillimeter precision using steps of 50 μm. The system is designed to deliver a maximum dose rate of 40 Gy/ min.These irradiators are operated under a common small animal irradiation facility that accepts campus wide preclinical projects. We will conclude our presentation by presenting examples of ongoing radiobiological projects that will allow us to illustrate the performance and operation of both irradiators.
TU‐C‐BRD‐07: Translational Research with Small Animal IGRT
Authors: Hope A , Lindsay P , Hill R , Jaffray D 
Published: April 2010

Radiation therapy is a critical component in the management of cancer. However, our understanding of radiotherapy must continue to grow with improvements in conformality (e.g., IMRT) and as more targeted agents become available. Maximizing the therapeutic ratio will require a thorough understanding of biology of tumors and normal tissues. Small animal models of tumor response and normal tissue toxicity can provide unique insights into these issues, but have inherent limitations and challenges which must be overcome. As small animal image‐guided radiation therapy (IGRT) becomes feasible, one of the most important issues becomes “What questions do we want to ask?”. Pure radiotherapy questions such as dose, volume, and time/fractionation can be explored in appropriate small animal tumor models while monitoring normal tissue effects. When combined with the ever‐increasing number of targeted agents, small animal IGRT becomes a powerful pre‐clinical tool that may allow optimal selection of agents and improve the timing and sequencing of concurrent therapies. After strong models of tumor control and normal tissue response are established, exploration of response biomarkers including novel imaging modalities becomes feasible. The wide‐spread availability of small animal multi‐modality imaging including CT, MR, optical, and US combined with novel contrast agents makes this an especially rich area of exploration. Some examples of previous small animal radiotherapy experiments with a brain tumor model and ongoing exploration of normal tissues effects in lung will be reviewed and potential future studies attempting to link pre‐clinical and clinical data will be outlined.Learning Objectives:At the end of this lecture, the audience will be able to:1. Describe some of the challenges of small animal models.2. Discuss the range of biologic experiments which may be feasible.
TU‐C‐BRB‐08: Validating Normal Tissue Complication Probability Models: A Study of Generalizability and Datapooling for Predictive Radiation Pneumonitis Modeling
Authors: Huang E , Bradley J , El Naqa I , Trovo M , Deasy J 
Published: April 2010

Purpose: NTCP models usually do not undergo needed tests of external validation or generalizability for eventual clinical use. Here we test and generalize an NTCP model for predicting radiation pneumonitis (RP) using data‐pooling with institutional data and a multi‐institutional dataset (RTOG 93‐11 data). As accurate dosimetry is unavailable for the RTOG dataset, non‐heterogeneity corrected dose distributions were used throughout. Methods and Materials: Data consisted of 313 patients who received definitive conformal radiotherapy for non‐small‐cell lung cancer (209 from WUSTL, 104 from the RTOG 93‐11 trial). For each individual subset patient groups, heart and lung dosimetric variables (abstracted from corresponding treatment planning archives), existing clinical factors, and tumor/high‐dose positional parameters are included in multivariate logistic regression modeling to obtain the most predictive multi‐variable NTCP model. Cross‐validation and bootstrapping methods were used confirm internal model validity, model stability, and optimal model size. The derived best model for each dataset was tested against the other dataset. Finally, modeling over the combined multi‐instructional dataset (RTOG 93‐11 trial and WUSTL datasets) was conducted and the resulting model was tested against each individual subset of data. Results: Models derived on the separate datasets performed poorly on the other dataset. However, the best model derived on the full dataset included D10_heart, D10_lung, and center‐of‐GTV‐mass‐superior‐inferior. which performed well over each individual subset. Conclusion: These results demonstrate the unique role that full 3‐D data‐pooling can play: models can be derived that work across a wide spectrum of patient datasets, but the actual target populations should be included in the analysis.Supported by NIH grant R01 CA85181.