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At least 1,549 records · Page 86

MO-E-BRD-00: Breast Brachytherapy: The Phoenix of Radiation Therapy

Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current clinical trials for IORT To discuss lumpectomy-scan-plan-treat workflow for IORT.

60 APPLIED LIFE SCIENCES↗

MO-E-BRD-01: Is Non-Invasive Image-Guided Breast Brachytherapy Good?

Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current clinical trials for IORT To discuss lumpectomy-scan-plan-treat workflow for IORT.

60 APPLIED LIFE SCIENCES↗

MO-E-BRD-02: Accelerated Partial Breast Irradiation in Brachytherapy: Is Shorter Better?

Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current clinical trials for IORT To discuss lumpectomy-scan-plan-treat workflow for IORT.

60 APPLIED LIFE SCIENCES↗

MO-E-BRD-03: Intra-Operative Breast Brachytherapy: Is One Stop Shopping Best? [ Non-invasive Image-Guided Breast Brachytherapy ]

Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current clinical trials for IORT To discuss lumpectomy-scan-plan-treat workflow for IORT.

60 APPLIED LIFE SCIENCES↗

Dynamic test/analysis correlation using reduced analytical models

Test/analysis correlation is an important aspect of the verification of analysis models which are used to predict on-orbit response characteristics of large space structures. This paper presents results of a study using reduced analysis models for performing dynamic test/analysis correlation. The reduced test-analysis model (TAM) has the same number and orientation of DOF as the test measurements. Two reduction methods, static (Guyan) reduction and the Improved Reduced System (IRS) reduction, are applied to the test/analysis correlation of a laboratory truss structure. Simulated test results and modal test data are used to examine the performance of each method. It is shown that selection of DOF to be retained in the TAM is critical when large structural masses are involved. In addition, the use of modal test results may provide difficulties in TAM accuracy even if a large number of DOF are retained in the TAM.

Mcgowan, Paul E.↗

Combined Limb-Sparing Surgery and Radiation Therapy to Treat Sarcomas of the Hands and Feet: Long-Term Cancer Outcomes and Morbidity

Purpose: The purpose of this study was to investigate local control, survival outcomes, and complication rates of patients treated with limb-sparing surgery and radiation therapy (RT) for soft tissue sarcomas (STS) of the hands and feet. Methods and Materials: We reviewed the medical records of 85 consecutive patients treated for STS of the hands (n=38, 45%) and feet (n=47, 55%) between 1966 and 2012. The median age was 41 years (range, 10-82 years of age). Sixty-seven patients (79%) received postoperative RT after resection of their tumor (median dose, 60 Gy; range, 45-70 Gy). The remaining 18 patients (21%) were treated with preoperative RT followed by tumor resection (median dose, 50 Gy; range, 50-64 Gy). Results: Median follow-up was 140 months (range, 24-442 months). Five-year local control, overall survival, and disease-specific survival rates were 86%, 89%, and 89%, respectively. Positive or uncertain surgical margin status was the only factor adversely associated with local recurrence (19% vs 6% for negative margins, P=.046) but this lost significance on multivariate analysis when adjusting for RT dose ≥64 Gy. Of the 12 patients who had local relapses, 6 (50%) were salvaged, and only 2 of those required salvage amputation. Five patients had grade ≥3 late RT sequelae, with 2 patients (2%) having moderate limitations of limb function and 3 patients (4%) having severe limitations requiring procedures for skin ulceration. Conclusions: Limb-sparing surgery combined with RT provides excellent local control outcomes for sarcomas arising in the hands or feet. In patients who have local recurrence, salvage without amputation is possible. The excellent cancer control outcomes observed, considering the minimal impact on limb function, support use of combined modality, limb-sparing local therapy for STS arising in the hands or feet.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Assessment of Interfraction Patient Setup for Head-and-Neck Cancer Intensity Modulated Radiation Therapy Using Multiple Computed Tomography-Based Image Guidance

Purpose: Various image guidance systems are commonly used in conjunction with intensity modulated radiation therapy (IMRT) in head-and-neck cancer irradiation. The purpose of this study was to assess interfraction patient setup variations for 3 computed tomography (CT)-based on-board image guided radiation therapy (IGRT) modalities. Methods and Materials: A total of 3302 CT scans for 117 patients, including 53 patients receiving megavoltage cone-beam CT (MVCBCT), 29 receiving kilovoltage cone-beam CT (KVCBCT), and 35 receiving megavoltage fan-beam CT (MVFBCT), were retrospectively analyzed. The daily variations in the mediolateral (ML), craniocaudal (CC), and anteroposterior (AP) dimensions were measured. The clinical target volume-to-planned target volume (CTV-to-PTV) margins were calculated using 2.5Σ + 0.7 σ, where Σ and σ were systematic and random positioning errors, respectively. Various patient characteristics for the MVCBCT group, including weight, weight loss, tumor location, and initial body mass index, were analyzed to determine their possible correlation with daily patient setup. Results: The average interfraction displacements (± standard deviation) in the ML, CC, and AP directions were 0.5 ± 1.5, −0.3 ± 2.0, and 0.3 ± 1.7 mm (KVCBCT); 0.2 ± 1.9, −0.2 ± 2.4, and 0.0 ± 1.7 mm (MVFBCT); and 0.0 ± 1.8, 0.5 ± 1.7, and 0.8 ± 3.0 mm (MVCBCT). The day-to-day random errors for KVCBCT, MVFBCT, and MVCBCT were 1.4-1.6, 1.7, and 2.0-2.1 mm. The interobserver variations were 0.8, 1.1, and 0.7 mm (MVCBCT); 0.5, 0.4, and 0.8 mm (MVFBCT); and 0.5, 0.4, and 0.6 mm (KVCBCT) in the ML, CC, and AP directions, respectively. The maximal calculated uniform CTV-to-PTV margins were 5.6, 6.9, and 8.9 mm for KVCBCT, MVFBCT, and MVCBCT, respectively. For the evaluated patient characteristics, the calculated margins for different patient parameters appeared to differ; analysis of variance (ANOVA) and/or t test analysis found no statistically significant setup difference in any direction. Conclusions: Daily random setup errors and CTV-to-PTV margins for treatment of head-and-neck cancer were affected by imaging quality. Our data indicated that larger margins were associated with MVFBCT and MVCBCT, compared with smaller margins for KVCBCT. IGRT modalities with better image quality are encouraged in clinical practice.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Stiffnesses of a solid-rocket motor from an ambient vibration survey

Experience with many spacecraft configurations boosted by a variety of launch vehicles indicates that the maximum loads experienced throughout most of the structure are inertial in origin. These loads arise from the dynamic elastic response of the flight vehicle to the transient disturbances of launch and flight, and are highly dependent on the dynamic characteristics of both the spacecraft and the launch vehicle. It has proved to be most advantageous, in the analysis of this critical dependency of loads upon vehicle dynamic properties, to establish a mathematical model in terms of normal mode characteristics. In this way, the vibration behavior of an elastomechanical structure (or substructure) can be described by means of the so-called modal or natural degrees of freedom. The conduct of a mode survey test and the use of a suitably test-verified model in loads analyses is essential to the flight worthiness certification process of space systems. The desirability of such tests is confirmed by the fact that, almost invariably, significant deficiencies in the analytical models are revealed by the results. Therefore, this experimental program was undertaken to determine those properties of a solid-propellant rocket motor (SRM) which are required to characterize a dynamic model. Random ambient-excited accelerations were measured at a series of stations along the motor for the purpose of identifying the motor beam-like stiffnesses in bending, shear, and torsion. From a system identification point of view, it is significant that stiffness properties of a subsystem (the motor) are determined from modes of the full system (motor/stand configuration) using mode shape data of the subsystem only. This contrasts with traditional system identification approaches which rely upon complete system mode shapes.

Rubin, S.↗

Development and Validation of a Fast, Accurate and Cost-Effective Aeroservoelastic Method on Advanced Parallel Computing Systems

Progress to date towards the development and validation of a fast, accurate and cost-effective aeroelastic method for advanced parallel computing platforms such as the IBM SP2 and the SGI Origin 2000 is presented in this paper. The ENSAERO code, developed at the NASA-Ames Research Center has been selected for this effort. The code allows for the computation of aeroelastic responses by simultaneously integrating the Euler or Navier-Stokes equations and the modal structural equations of motion. To assess the computational performance and accuracy of the ENSAERO code, this paper reports the results of the Navier-Stokes simulations of the transonic flow over a flexible aeroelastic wing body configuration. In addition, a forced harmonic oscillation analysis in the frequency domain and an analysis in the time domain are done on a wing undergoing a rigid pitch and plunge motion. Finally, to demonstrate the ENSAERO flutter-analysis capability, aeroelastic Euler and Navier-Stokes computations on an L-1011 wind tunnel model including pylon, nacelle and empennage are underway. All computational solutions are compared with experimental data to assess the level of accuracy of ENSAERO. As the computations described above are performed, a meticulous log of computational performance in terms of wall clock time, execution speed, memory and disk storage is kept. Code scalability is also demonstrated by studying the impact of varying the number of processors on computational performance on the IBM SP2 and the Origin 2000 systems.

Goodwin, Sabine A.↗

NWA 2736: An Unusual New Graphite-bearing Aubrite

Aubrites are enstatite-rich achondrites that are probably related to enstatite chondrite parent bodies. The exact link, if any, is not understood. They may have formed from melting within one or more enstatite chondrite parent bodies. Description of NWA 2736: One complete stone weighing 171.51 grams was recovered from the Sahara Desert by nomads sometime before September 2004. It was completely covered with fusion crust and desert varnish. This stone is severely weathered, with caramel brown coloration throughout and calcite veins that extend into the interior of the sample. Mineral analyses were performed and elemental x-ray maps were obtained with a CAMECA SX-50 electron microprobe at the Lunar and Planetary Laboratory at the University of Arizona. The relatively high modal abundance of albitic plagioclase, presence of euhedral graphite, depletion of troilite, and occurrence of pervasive kamacite veins (some with daubreelite) all indicate that NWA 2736 has a complex history and may sample a new region of the aubrite parent body. A discussion and analysis on the overall texture of NWA 2736 is presented.

Lowe, J. J.↗

Shuttle Flight-7A DTO-261: Pre and Post Flight Analysis

This paper reports on the analysis to validate and correlate the analytical models of ISS-Shuttle Flight-7A configuration. On-orbit dynamic responses were measured during an intentional dynamic test (DTO-261) by the Shuttle video camera photogrammetric system and the Internal Wireless Instrumentation System (IWIS). Modal analyses were performed on the measured data to extract modal parameters including frequency, damping, and mode shapes. Correlation and comparisons between test and analytical modal parameters were performed to assess the accuracy of the models.

Kaouk, Mohamed↗

Initial Site-Specific Studies for Removing SNF from Six Shutdown Sites - 18042

The US Department of Energy (DOE) is exploring options for developing a large-scale transportation system for the safe transport of spent nuclear fuel (SNF) and high-level radioactive waste to future storage or disposal facilities. This complex, large-scale transportation system will involve coordinated, integrated activities. Interfaces with various transportation and non-transportation activities must be defined, and systems must be developed to ensure successful integration when the system becomes operational. To provide an understanding of the tasks and interfaces required for the complete de-inventory of particular sites where SNF is stored, DOE solicited bids from integrating contractors to develop initial site-specific de-inventory reports. The reports were developed for several nuclear power plant sites selected to represent a range of geographic locations, existing on-site SNF storage systems, and expected transportation modal options. Each report is presented in a self-contained narrative describing a potential campaign for removing all SNF and greater-than-class-C low-level radioactive waste (GTCC waste) from each specified site. Each study narrative includes site information; an analysis of the near-site transportation infrastructure; a concept of operations for the de-inventory; an estimated budget and schedule for the duration of operations; and a safety and security plan with site-specific considerations, emergency response considerations, and recommendations for the next steps DOE could take to de-inventory the site. The reports provide cost estimates for analytical purposes only; they do not attempt to specify the party or parties responsible for the costs. These reports present a first look at how an integrating contractor might recommend removing SNF from particular sites. They are written from the perspective of the contractor and do not represent DOE's plans. At this writing, six sites have been studied: - Connecticut Yankee, - Big Rock Point, - Humboldt Bay, - Maine Yankee, - Trojan, - Kewaunee. DOE may develop de-inventory reports for all reactor sites, with an initial focus on shutdown reactor sites. The order in which sites have been selected for study should not be considered an indicator of the order used by DOE to remove SNF from the sites. Since the SNF's destination is not important for the purpose of this work, DOE tasked the contractor with planning transportation of the SNF from the site to a generic railroad location in the approximate geographical center of the United States. These reports represent an initial study of the specific sites. Per the terms of the contract, the contractor was not permitted to engage in dialogue with power plant site personnel; near-site railroad personnel; or any local, state, or regional stakeholders about the studies. DOE provided site-specific data. The contractor was tasked to rely on past corporate experience, data available from DOE, and publicly available data when making site-specific recommendations for removing all SNF from each site. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

SU-E-J-218: Novel Validation Paradigm of MRI to CT Deformation of Prostate

Purpose: Deformable registration algorithms are inherently difficult to characterize in the multi-modality setting due to a significant differences in the characteristics of the different modalities (CT and MRI) as well as tissue deformations. We present a unique paradigm where this is overcome by utilizing a planning-MRI acquired within an hour of the planning-CT serving as a surrogate for quantifying MRI to CT deformation by eliminating the issues of multi-modality comparisons. Methods: For nine subjects, T2 fast-spin-echo images were acquired at two different time points, the first several weeks prior to planning (diagnostic-MRI) and the second on the same day as the planning-CT (planning-MRI). Significant effort in patient positioning and bowel/bladder preparation was undertaken to minimize distortion of the prostate in all datasets. The diagnostic-MRI was rigidly and deformably aligned to the planning-CT utilizing a commercially available deformable registration algorithm synthesized from local registrations. Additionally, the quality of rigid alignment was ranked by an imaging physicist. The distances between corresponding anatomical landmarks on rigid and deformed registrations (diagnostic-MR to planning-CT) were evaluated. Results: It was discovered that in cases where the rigid registration was of acceptable quality the deformable registration didn’t improve the alignment, this was true of all metrics employed. If the analysis is separated into cases where the rigid alignment was ranked as unacceptable the deformable registration significantly improved the alignment, 4.62mm residual error in landmarks as compared to 5.72mm residual error in rigid alignments with a p-value of 0.0008. Conclusion: This paradigm provides an ideal testing ground for MR to CT deformable registration algorithms by allowing for inter-modality comparisons of multi-modality registrations. Consistent positioning, bowel and bladder preparation may Result in higher quality rigid registrations than typically achieved which limits the impact of deformable registrations. In this study cases where significant differences exist, deformable registrations provide significant value.

60 APPLIED LIFE SCIENCES↗

Blade loss transient dynamics analysis, volume 2. Task 2: TETRA 2 user's manual

This is the user's manual for the TETRA 2 Computer Code, a program developed in the NASA-Lewis Blade Loss Program. TETRA 2 calculates a turbine engine's dynamic structural response from applied stimuli. The calculation options are: (1) transient response; and (2) steady state forced response. Based on the method of modal syntheses, the program allows the use of linear, as well as nonlinear connecting elements. Both transient and steady state options can include: flexible Bladed Disk Module, and Nonlinear Connecting Elements (including deadband, hardening/softening spring). The transient option has the additional capability to calculate response with a squeeze film bearing module. TETRA 2 output is summarized in a plotfile which permits post processing such as FFT or graphical animation with the proper software and computer equipment.

Black, Gerald↗

Endovascular Recanalization of Thromboangiitis Obliterans (Buerger’s Disease) in Twenty-Eight Consecutive Patients and Combined Antegrade–Retrograde Intervention in Eight Patients

Purpose: The aim of the study was to evaluate the technical success of the procedure and the clinical efficacy of treatment in patients with thromboangiitis obliterans (TAO) (Buerger’s disease) based on a change in the Rutherford classification. Materials and Methods: A total of 28 consecutive patients (26 males, 2 females, mean age 43.3 ± 5.32 years) underwent endovascular recanalization with a diagnosis of TAO, between April 2015 and July 2018. After unsuccessful attempts using the antegrade approach, retrograde approaches were used in 8 patients under ultrasound guidance. Clinical follow-up was routinely performed at 1-month, 3-month, 6-month, and 1-year intervals. Results: A total of 28 TAO patients underwent 40 procedures in 32 limbs. Technical success was achieved in 28 of the 32 limbs (87.5%). In total, 45 of 59 (76.2%) below the knee arteries were treated successfully. One major amputation was performed, providing a 96.8% rate for limb salvage both at 12 and 24 months. Amputation-free survival estimated by Kaplan–Meier analysis was 84% at 12 and 24 months. Primary patency rates at 12, 24, and 36 months were 84%, 78%, and 75%, respectively. Secondary patency rates were 87.5% both at 12 and 24 months. Conclusion: Endovascular treatment is a technically feasible and potentially effective treatment modality for Buerger’s disease. Combined antegrade and retrograde interventions in TAO patients may improve technical success and clinical recovery, especially in cases where the antegrade approach has failed.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Data-Driven Invertible Neural Surrogates of Atmospheric Transmission

We present Data-Driven Invertible Neural Surrogates of Atmospheric transmission, or DINSAT. DINSAT is a novel framework for inferring an atmospheric transmission profile from a spectral scene. This framework leverages a lightweight, physics-based simulator that is automatically tuned -- by virtue of autodifferentiation and differentiable programming -- to construct a surrogate atmospheric profile to model the observed data. The framework has utility in (i) performing atmospheric correction, (ii) recasting spectral data between various modalities (e.g. radiance and reflectance at the surface and at the sensor), and (iii) inferring atmospheric transmission profiles, such as absorbing bands and their relative magnitudes. We demonstrate the utility of these methods by performing a canonical atmospheric correction task for the purposes of further analysis - in this case, target detection within a scene.

Koch, James V.↗

SU-E-J-253: The Radiomics Toolbox in the Computational Environment for Radiological Research (CERR)

Purpose: To present an open source and free platform to facilitate radiomics research — The “Radiomics toolbox” in CERR. Method: There is scarcity of open source tools that support end-to-end modeling of image features to predict patient outcomes. The “Radiomics toolbox” strives to fill the need for such a software platform. The platform supports (1) import of various kinds of image modalities like CT, PET, MR, SPECT, US. (2) Contouring tools to delineate structures of interest. (3) Extraction and storage of image based features like 1st order statistics, gray-scale co-occurrence and zonesize matrix based texture features and shape features and (4) Statistical Analysis. Statistical analysis of the extracted features is supported with basic functionality that includes univariate correlations, Kaplan-Meir curves and advanced functionality that includes feature reduction and multivariate modeling. The graphical user interface and the data management are performed with Matlab for the ease of development and readability of code and features for wide audience. Open-source software developed with other programming languages is integrated to enhance various components of this toolbox. For example: Java-based DCM4CHE for import of DICOM, R for statistical analysis. Results: The Radiomics toolbox will be distributed as an open source, GNU copyrighted software. The toolbox was prototyped for modeling Oropharyngeal PET dataset at MSKCC. The analysis will be presented in a separate paper. Conclusion: The Radiomics Toolbox provides an extensible platform for extracting and modeling image features. To emphasize new uses of CERR for radiomics and image-based research, we have changed the name from the “Computational Environment for Radiotherapy Research” to the “Computational Environment for Radiological Research”.

60 APPLIED LIFE SCIENCES↗