bluuebunny/crossref_metadata_2025 huggingface dataset:
TU‐CD‐BRB‐10: 18F‐FDG PET Image‐Derived Tumor Features Highlight Altered Pathways Identified by Trancriptomic Analysis in Head and Neck Cancer
Authors: Tixier F , Cheze‐Le‐Rest C , Hatt M , Dufour X , Valette G , Potard G , Corcos L , Visvikis D
Published: June 2015

Purpose:

Several quantitative features can be extracted from 18F‐FDG PET images, such as standardized uptake values (SUVs), metabolic tumor volume (MTV), shape characterization (SC) or intra‐tumor radiotracer heterogeneity quantification (HQ). Some of these features calculated from baseline 18F‐FDG PET images have shown a prognostic and predictive clinical value. It has been hypothesized that these features highlight underlying tumor patho‐physiological processes at smaller scales. The objective of this study was to investigate the ability of recovering alterations of signaling pathways from FDG PET image‐derived features.

Methods:

52 patients were prospectively recruited from two medical centers (Brest and Poitiers). All patients underwent an FDG PET scan for staging and biopsies of both healthy and primary tumor tissues. Biopsies went through a transcriptomic analysis performed in four spates on 4×44k chips (Agilent™). Primary tumors were delineated in the PET images using the Fuzzy Locally Adaptive Bayesian algorithm and characterized using 10 features including SUVs, SC and HQ. A module network algorithm followed by functional annotation was exploited in order to link PET features with signaling pathways alterations.

Results:

Several PET‐derived features were found to discriminate differentially expressed genes between tumor and healthy tissue (fold‐change >2, p<0.01) into 30 co‐regulated groups (p<0.05). Functional annotations applied to these groups of genes highlighted associations with well‐known pathways involved in cancer processes, such as cell proliferation and apoptosis, as well as with more specific ones such as unsaturated fatty acids.

Conclusion:

Quantitative features extracted from baseline 18F‐FDG PET images usually exploited only for diagnosis and staging, were identified in this work as being related to specific altered pathways and may show promise as tools for personalizing treatment decisions.
TU‐CD‐BRB‐11: A Spatiotemporal Image Phenotyping Pipeline for Radiogenomic Profiling of Breast Cancer with DCE MRI
Authors: Kim J , Kim Y , Yang Z , Hong B , Kuo M , Han W , Yamamoto S , Jamshidi N
Published: June 2015

Purpose:

Objective and quantitative radiophenotyping from cancer patients is a core requirement of radiogenomic research. We present our quantitative image phenotyping pipeline which is tuned to extract spatiotemporal tumor traits from DCE breast MRI and initial results of radiogenomic association between spatiotemporal imaging features and RNA expression in breast cancer

Methods:

DCE MRI with 5 enhancement phases of 61 breast cancer patients were analyzed. A unified energy functional was defined for a joint shape and temporal motion estimation which incorporates intensity variation within a region along with kinetic signature. A level set evolution was carried out under the guidance of the unified energy functional to generate tumor probability maps, which is then thresholded to produce tumor masks. Among them, the observer selected the largest one. A total of 47 features were extracted from the segmented tumor comprising geometric, statistical, and spatiotemporal features. The whole procedure was carried out independently by two observers. Features from 19 cases were used as a training set to discover a prognostic imaging biomarker indicative of poor metastasis‐free survival, and the remaining 39 cases were used for validation.In addition, association between the predictive imaging biomarker and genomic profiles were assessed using RNA expression data of these matched patients obtained with next‐generation RNA sequencing and RT‐PCR.

Results:

All imaging features from two independent analysis were highly consistent (r > 0.78, p<0.001). Among them, a spatiotemporal feature (enhancing rim fraction score, ERF) was shown to be strongly predictive of early metastasis (P =.009; hazard ratio,16.3; 95% confidence interval: 1.99). Radiogenomic analysis revealed five named lncRNAs significantly associated with high ERF score.

Conclusion:

A quantitative image phenotyping pipeline was developed which provides objective spatiotemporal features and could be successfully utilized in radiogenomic profiling of breast cancer.
TU‐CD‐303‐01: Memorial to Warren Sinclair ‐ Memorial Lecturer
Authors: Grissom M
Published: June 2015

The Medical Physics and Radiation Protection communities lost one of their true pioneers in May, 2014 with the passing of Warren K. Sinclair, Ph.D. He received his Doctorate in Physics at the University of London, U.K. He was a fellow of the Institute of Physics and a Certified Health Physicist. After a number of posts at Hospitals and Universities in the U.K. and New Zealand, he became the Head, Physics Department at the M.D. Anderson Hospital, Houston, TX. He held a number of academic physics positions with the University of Texas, Austin at the main campus and at the Postgraduate School of Medicine, Houston. He later served as a Senior Biophysicist, Division Director, and then Associate Laboratory Director for Biomedical Division Director, and then Associate Laboratory Director for Biomedical and Environmental Research at the Argonne National Laboratory, IL. He had additional academic appointments at the University of California, Berkeley; Northern Illinois University; the University of Illinois (Chicago Circle Campus); and the University of Chicago.

Warren was a charter member of the AAPM and a leader in many communities: President of the AAPM from 1960 to 1961 and the Journal Editor from 1964 to 1969, the 2nd President of the NCRP from 1977 to 1991, and the President of the Radiation Research Society from 1978 to 1979. His many awards included the William D. Coolidge Award in 1986. Even this barely scratches the surface of the many other organizations he served with and influenced including the ICRP, IOP, RSNA, SNM, and UNSCEAR. His research interests resulted in publications from 1948 to the 1990s in many aspects (physical and biological) of radiotherapy and the effects of ionizing radiation in general, leading to early definitions of RBE values for megavoltage radiotherapy as well as contributing to the development of the modern framework for radiation protection worldwide.

Warren was not a retiring person and even after moving to NCRP President Emeritus status continued to provide advice and comments on publications and to mentor others until the time of his passing. Sadly, Warren's long‐time wife Joy passed away in December, 2014 but he is survived by his son Bruce and daughter Roslyn, 2 grandchildren and 4 great‐grandchildren.
TU‐EF‐303‐00: Bridging the Scales From Molecules and Cells to Clinical Applications
Authors: Jeraj Robert
Published: June 2015

Many medical physics diagnostic and therapeutic developments have significant overlap with biophysical approaches to measuring and modeling molecular and cellular systems. Although these methods may differ dramatically in terms of temporal and spatial scales, many of the underlying concepts are identical, suggesting potential synergies across the scales. For example, while clinical imaging is typically in the (sub)millimeter and second regime, biophysical imaging technologies reach sub‐nanometer and sub‐picosecond scales. Despite these scale differences, the use of molecular labeling, resulting large datasets, and need for quantitative analysis methods are similar, and solutions developed for one application are easily translated to others. Similarly, mathematical models used to understand clinical responses are often based on molecular and cellular networks that have been elucidated by biophysical studies. In turn, such models are directly useful for guiding on‐going biophysical and biomedical research. Relevant biophysical applications are found in the cancer, neuroscience, and cardiac fields, which are also research focus areas for many AAPM members. Presentations by physicists working in biophysics will explore potential synergies with diagnostic and therapeutic medical physics, as well as help identify areas of common interest that would be ripe for novel collaborations.

Learning Objectives:

1.To learn about differences in temporal and spatial scales of medical physics and biophysics

To learn about common methods used in medical physics and biophysics

To learn about synergistic opportunities between medical physics and biophysics
TU‐EF‐303‐02: Fluorescence‐Guided Neurosurgery
Authors: Pogue B.
Published: June 2015

Many medical physics diagnostic and therapeutic developments have significant overlap with biophysical approaches to measuring and modeling molecular and cellular systems. Although these methods may differ dramatically in terms of temporal and spatial scales, many of the underlying concepts are identical, suggesting potential synergies across the scales. For example, while clinical imaging is typically in the (sub)millimeter and second regime, biophysical imaging technologies reach sub‐nanometer and sub‐picosecond scales. Despite these scale differences, the use of molecular labeling, resulting large datasets, and need for quantitative analysis methods are similar, and solutions developed for one application are easily translated to others. Similarly, mathematical models used to understand clinical responses are often based on molecular and cellular networks that have been elucidated by biophysical studies. In turn, such models are directly useful for guiding on‐going biophysical and biomedical research. Relevant biophysical applications are found in the cancer, neuroscience, and cardiac fields, which are also research focus areas for many AAPM members. Presentations by physicists working in biophysics will explore potential synergies with diagnostic and therapeutic medical physics, as well as help identify areas of common interest that would be ripe for novel collaborations.

Learning Objectives:

1.To learn about differences in temporal and spatial scales of medical physics and biophysics

To learn about common methods used in medical physics and biophysics

To learn about synergistic opportunities between medical physics and biophysics
TU‐EF‐303‐04: Multi‐Modal in Vivo Cellular Imaging of Embryonic Heart Morphogenesis
Authors: Liebling M.
Published: June 2015

Many medical physics diagnostic and therapeutic developments have significant overlap with biophysical approaches to measuring and modeling molecular and cellular systems. Although these methods may differ dramatically in terms of temporal and spatial scales, many of the underlying concepts are identical, suggesting potential synergies across the scales. For example, while clinical imaging is typically in the (sub)millimeter and second regime, biophysical imaging technologies reach sub‐nanometer and sub‐picosecond scales. Despite these scale differences, the use of molecular labeling, resulting large datasets, and need for quantitative analysis methods are similar, and solutions developed for one application are easily translated to others. Similarly, mathematical models used to understand clinical responses are often based on molecular and cellular networks that have been elucidated by biophysical studies. In turn, such models are directly useful for guiding on‐going biophysical and biomedical research. Relevant biophysical applications are found in the cancer, neuroscience, and cardiac fields, which are also research focus areas for many AAPM members. Presentations by physicists working in biophysics will explore potential synergies with diagnostic and therapeutic medical physics, as well as help identify areas of common interest that would be ripe for novel collaborations.

Learning Objectives:

1.To learn about differences in temporal and spatial scales of medical physics and biophysics

To learn about common methods used in medical physics and biophysics

To learn about synergistic opportunities between medical physics and biophysics
TU‐EF‐204‐04: Feasibility Study of a Novel Stationary Spectral CT Scanner
Authors: Xu P , Xing X , Zheng J , Chen S , Zhang Y , Yuan G , Sun M
Published: June 2015

Purpose:

To evaluate a cadmium zinc telluride (CZT) detector module and to develop a proof‐of‐concept bench‐top system to examine the concept and feasibility of a stationary spectral scanner that would consist of a CZT detector ring and a distributed source for rotationless imaging.

Methods:

The bench‐top system employs a double‐rotation set‐up with two concentric but independent rotating stages, one for turning the object at sparse angles to mimic the imaging from a sequentially activated source distributed on a ring, while the other for translating the detector module to simulate a projection arc along a virtual detector ring. A source of 30‐degree fan is used in the set‐up, and the ring is designed to be 85cm in diameter in order to provide a 22cm field‐of‐view that is large enough for an average human head. The CZT detector module has 16×16 0.5mm pixels and eight global energy thresholds, and is attached to an experimental data acquisition board from the same vendor (Nova R&D). Its pixel gain is first calibrated using radioisotope Tc‐99m to align the photo‐peaks. Count rate performance is assessed using the X‐ray source. Air and offset corrections are done prior to each CT scan. A 10cm acrylic phantom with 5 different inserts is imaged at 100kVp, 2mA, with an effective exposure window of 150ms per projection. Reconstruction is done using a total variation‐type iterative method.

Results:

The detector module exhibited large gain variations among pixels. Average count rate was over 1Mcps per pixel. Parallax effect was observed along the arcs but was corrected. Reconstructed images from two energy bins demonstrated good contrast, spatial resolution and image uniformity, with little artifacts.

Conclusion:

The CZT detector tested is suitable for imaging relatively small objects. A stationary spectral CT appears feasible should we have enough buttable modules and a distributed source.

This work was supported by Ministry of Science and Technology of China through grants 11YQ040082 and 2012BAI13B04.
TU‐EF‐204‐05: Task‐Driven Cerebral CT Perfusion Imaging
Authors: Li Ke , Niu Kai , Wu Yijing , Yang Pengfei , Chen Guang‐Hong
Published: June 2015

Purpose:

This work introduces a task‐driven framework to cerebral CT perfusion (CTP) imaging to improve the image quality and quantification accuracy of parametric perfusion maps used in the clinical assessment of acute ischemic strokes and stroke mimics.

Methods:

First, the concepts of cerebral anatomical noise, noise power spectrum (NPS), MTF, and generalized task‐based detectability index were developed for CTP imaging. Second, a spatial‐temporal (4D) cascaded system model was developed to establish an analytical and quantitative correspondence between system parameters and CTP imaging performance. Third, a library of CTP imaging tasks such as the detection of ischemic lesions with different sizes and severities of perfusion deficiencies were created under the guidance of a neurosurgeon. Finally, data acquisition, reconstruction, and processing parameters were prospectively optimized for each CTP imaging task for improved imaging performance. The proposed method was validated in both digital anthropomorphic 4D perfusion phantoms and in vivo canine stroke models.

Results:

The NPS, MTF, and the generalized task‐based detectability index predicted by the 4D cascaded model matched exactly with the experimental results. For both non‐deconvolution‐based and deconvolution‐based perfusion calculation methods, as long as the signal and noise properties of the input source CT images are known, the image quality and bias of the final CTP maps can be predicted. Guided by the tasked‐driven framework, a novel tube current modulation technique for the acquisition of source images was developed, and parameters involved in parametric perfusion map calculations were optimized. Through these innovations, perfusion maps of the canines demonstrated 80% reduction in image noise as well as significant improvement in the detectability of ischemic lesions and the quantitative accuracy of perfusion measurements.

Conclusion:

The task‐driven approach has successfully guided the improvement of conventional CTP imaging techniques, potentially enabling a leap in the image quality and quantification accuracy of parametric perfusion maps.

K. Li, K. Niu, Y. Wu, P. Yang: Nothing to disclose. G.‐H. Chen: Research funded, GE Healthcare; Research funded, Siemens AX.
TU‐EF‐204‐06: Waveform Measurements On a Fast‐KV Switching CT System
Authors: Nute J , Shepard S , Jacobsen M , Cody D
Published: June 2015

Purpose:

To evaluate the timing and shape of the kilovoltage (kV) waveform for a fast‐kV switching dual‐energy CT system using a non‐invasive method.

Methods:

A kV divider with mobile filter pack was connected to a digital oscilloscope and scanned using a fast‐kV switching dual‐energy CT system in service mode. The tube was stationary, so exposure time was equivalent to rotation time. In this system, the generator switches quickly between two nominal voltages of 80kV and 140kV. The predicted waveform period was calculated given 1968 projections per exposure/rotation. Two Gemstone Spectral Imaging (GSI) service settings, GSI‐2 and GSI‐3, with exposure times of 0.8sec and 0.5sec, respectively, were analyzed. The data were binned into high (>110kV) and low (<110kV) projection regions. Waveform periods were calculated using the intersections of the waveform with 110kV. The waveform was analyzed for period accuracy, minimum and maximum kV, and average kV of the high and low kV projection regions. The effective spectral separation was the difference between the average kVs of the low and high projection regions.

Results:

The shape of the waveform was neither square nor sinusoidal. The minimum and maximum kVs were 81.6kV and 139.6kV for GSI‐2 (0.8sec) and 84.8kV and 131.6kV for GSI‐3 (0.5sec), which were within 6% of the nominal kVs. GSI‐2 and GSI‐3 had average waveform periods of 0.8134msec and 0.5064msec, respectively, within 0.5% of the calculated periods. The average kV for the high and low projections yielded effective spectral separations of 38.3kV (89.2kV to 127.5kV) for GSI‐2 (0.8sec) and 27.2kV (93.7kV to 121.4kV) for GSI‐3 (0.5sec).

Conclusion:

A method for analyzing the kV waveform of a fast‐kV switching x‐ray tube was demonstrated. The pseudo‐sinusoidal shape of the kV waveform lowers spectral separation compared to that of an ideal square wave, which may impact the quality of dual‐energy CT material decomposition.

This research was conducted at the MD Anderson Center for Advanced Biomedical Imaging in‐part with equipment support from General Electric Healthcare
TU‐EF‐204‐07: Add Tube Current Modulation to a Low Dose Simulation Tool for CT Systems
Authors: Ding Y. , Wen G. , Brown K. , Klahr P. , Dhanantwari A.
Published: June 2015

Purpose:

We extended the capabilities of a low dose simulation tool to model Tube‐Current Modulation (TCM). TCM is widely used in clinical practice to reduce radiation dose in CT scans. We expect the tool to be valuable for various clinical applications (e.g., optimize protocols, compare reconstruction techniques and evaluate TCM methods).

Methods:

The tube current is input as a function of z location, instead of a fixed value. Starting from the line integrals of a scan, a new Poisson noise realization at a lower dose is generated for each view. To validate the new functionality, we compared simulated scans with real scans in image space.

Results:

First we assessed noise in the difference between the low‐dose simulations and the original high‐dose scan. When the simulated tube current is a step function of z location, the noise at each segment matches the noise of 3 separate constant‐tube‐current‐simulations. Secondly, with a phantom that forces TCM, we compared a low‐dose simulation with an equivalent real low‐dose scan. The mean CT number of the simulated scan and the real low‐dose scan were 137.7±0.6 and 137.8±0.5 respectively. Furthermore, with 240 ROIs, the noise of the simulated scan and the real low‐dose scan were 24.03±0.45 and 23.99±0.43 respectively, and they were not statistically different (2‐sample t‐test, p‐value=0.28). The facts that the noise reflected the trend of the TCM curve, and that the absolute noise measurements were not statistically different validated the TCM function.

Conclusion:

We successfully added tube‐current modulation functionality in an existing low dose simulation tool. We demonstrated that the noise reflected an input tube‐current modulation curve. In addition, we verified that the noise and mean CT number of our simulation agreed with a real low dose scan.

The authors are all employees of Philips. Yijun Ding is also supported by NIBIB P41EB002035 and NIBIB R01EB000803.
TU‐EF‐204‐08: Dose Efficiency of Added Beam‐Shaping Filter with Varied Attenuation Levels in Lung‐Cancer Screening CT
Authors: Ma C , Yu L , Vrieze T , Leng S , Fletcher J , McCollough C
Published: June 2015

Purpose:

Added filtration such as tin filter has the potential to improve dose efficiency of x‐ray beam in lung‐cancer screening CT. However, dose efficiency with added beam filtration is highly dependent on patient attenuation level. In this phantom study, we evaluated the image quality at different tube voltages with and without added tin filter when attenuation level varies.

Methods:

A 30 × 20 cm anthropomorphic thorax phantom with three added extension rings were used to simulate small (S), medium (M), large (L), and extra‐large (XL) adult patients. These phantoms were scanned on a 192‐slice CT scanner (Force, Siemens) at 100 and 120kV without tin filtration, and 100 and 150 kV with tin filtration (100Sn and 150Sn), at multiple dose levels at each kV. Images were reconstructed using iterative reconstruction (ADMIRE, Siemens). Radiation dose was measured with a 0.6 cc ion chamber in the middle and peripheral areas of the phantom. Image quality was assessed using mean image noise at uniform areas in the central region and lung. Radiation dose that is required for each kV to match the noise in a routine lung‐cancer CT screening technique (120kV, 25 quality reference mAs) was calculated.

Results:

At each of the four phantom sizes, 100Sn had the lowest noise in both soft tissue and lung. Compared with 120 kV, 100Sn saved 39%–60% dose for the same noise, depending on phantom size. For the XL phantom (50 by 40 cm), 150Sn provided images with the least beam‐hardening artifact in peripheral region.

Conclusion:

For thoracic CT, added tin filtration can provide considerable dose reduction compared with 120 kV. 100Sn provides better dose efficiencies for all phantom sizes, while 150Sn provides better image quality in peripheral region for extra‐large patients.

Drs.Joel G. Fletcher and Cynthia H. McCollough receive research support from Siemens Healthcare.
TU‐EF‐204‐10: A Preliminary Study Evaluating Calculation Variations of Local Noise Power Spectra for CT Simulation in Radiation Therapy
Authors: Dolly S , Chen H , Anastasio M , Mutic S , Li H
Published: June 2015

Purpose:

Local noise power spectrum (NPS) properties are significantly affected by calculation variables and CT acquisition and reconstruction parameters, but a thoughtful analysis of these effects is absent. In this study, we performed a complete analysis of the effects of calculation and imaging parameters on the NPS.

Methods:

The uniformity module of a Catphan phantom was scanned with a Philips Brilliance 64‐slice CT simulator using various scanning protocols. Images were reconstructed using both FBP and iDose4 reconstruction algorithms. From these images, local NPS were calculated for regions of interest (ROI) of varying locations and sizes, using four image background removal methods. Additionally, using a predetermined ground truth, NPS calculation accuracy for various calculation parameters was compared for computer simulated ROIs. A complete analysis of the effects of calculation, acquisition, and reconstruction parameters on the NPS was conducted.

Results:

The local NPS varied with ROI size and image background removal method, particularly at low spatial frequencies. The image subtraction method was the most accurate according to the computer simulation study, and was also the most effective at removing low frequency background components in the acquired data. However, first‐order polynomial fitting using residual sum of squares and principle component analysis provided comparable accuracy under certain situations. Similar general trends were observed when comparing the NPS for FBP to that of iDose4 while varying other calculation and scanning parameters. However, while iDose4 reduces the noise magnitude compared to FBP, this reduction is spatial‐frequency dependent, further affecting NPS variations at low spatial frequencies.

Conclusion:

The local NPS varies significantly depending on calculation parameters, image acquisition parameters, and reconstruction techniques. Appropriate local NPS calculation should be performed to capture spatial variations of noise; calculation methodology should be selected with consideration of image reconstruction effects and the desired purpose of CT simulation for radiotherapy tasks.
TU‐EF‐204‐11: Impact of Using Multi‐Slice Training Sets On the Performance of a Channelized Hotelling Observer in a Low‐Contrast Detection Task in CT
Authors: Favazza C , Yu L , Leng S , McCollough C
Published: June 2015

Purpose:

To investigate using multiple CT image slices from a single acquisition as independent training images for a channelized Hotelling observer (CHO) model to reduce the number of repeated scans for CHO‐based CT image quality assessment.

Methods:

We applied a previously validated CHO model to detect low contrast disk objects formed from cross‐sectional images of three epoxy‐resin‐based rods (diameters: 3, 5, and 9 mm; length: ∼5cm). The rods were submerged in a 35x 25 cm2 iodine‐doped water filled phantom, yielding‐15 HU object contrast. The phantom was scanned 100 times with and without the rods present. Scan and reconstruction parameters include: 5 mm slice thickness at 0.5 mm intervals, 120 kV, 480 Quality Reference mAs, and a 128‐slice scanner. The CHO's detectability index was evaluated as a function of factors related to incorporating multi‐slice image data: object misalignment along the z‐axis, inter‐slice pixel correlation, and number of unique slice locations. In each case, the CHO training set was fixed to 100 images.

Results:

Artificially shifting the object's center position by as much as 3 pixels in any direction relative to the Gabor channel filters had insignificant impact on object detectability. An inter‐slice pixel correlation of >∼0.2 yielded positive bias in the model's performance. Incorporating multi‐slice image data yielded slight negative bias in detectability with increasing number of slices, likely due to physical variations in the objects. However, inclusion of image data from up to 5 slice locations yielded detectability indices within measurement error of the single slice value.

Conclusion:

For the investigated model and task, incorporating image data from 5 different slice locations of at least 5 mm intervals into the CHO model yielded detectability indices within measurement error of the single slice value. Consequently, this methodology would Result in a 5‐fold reduction in number of image acquisitions.

This project was supported by National Institutes of Health grants R01 EB017095 and U01 EB017185 from the National Institute of Biomedical Imaging and Bioengineering.
TU‐EF‐204‐12: Quantitative Evaluation of Spectral Detector CT Using Virtual Monochromatic Images: Initial Results
Authors: Duan X , Arbique G , Guild J , Dhanantwari A , Yagil Y , Anderson J
Published: June 2015

Purpose

To evaluate the image quality and spectral information of a spectral detector CT (SDCT) scanner using virtual monochromatic (VM) energy images.

Methods

The SDCT scanner (Philips Healthcare) was equipped with a dual‐layer detector and spectral iterative reconstruction (IR), which generates conventional 80–140 kV polychromatic energy (PE) CT images using both detector layers, PE images from the low‐energy (upper) and high‐energy (lower) detector layers and VM images. A solid water phantom with iodine (2.0–20.0 mg I/ml) and calcium (50.0–600.0 mg Ca/ml) rod inserts was used to evaluate effective energy estimate (EEE) and iodine contrast to noise ratio (CNR). The EEE corresponding to an insert CT number in a PE image was calculated from a CT number fit to the VM image set. Since PE image is prone to beam‐hardening artifact EEE may underestimate the actual energy separation from two layers of the detector. A 30‐cm‐diameter water phantom was used to evaluate noise power spectrum (NPS). The phantoms were scanned at 120 and 140 kV with the same CTDIvol.

Results

The CT number difference for contrast inserts in VM images (50–150 keV) was 1.3±6% between 120 and 140 kV scans. The difference of EEE calculated from low‐ and high‐energy detector images was 11.5 and 16.7 keV for 120 and 140 kV scans, respectively. The differences calculated from 140 and 100 kV conventional PE images were 12.8, and 20.1 keV from 140 and 80 kV conventional PE images. The iodine CNR increased monotonically with decreased keV. Compared to conventional PE images, the peak of NPS curves from VM images were shifted to lower frequency.

Conclusion

The EEE results indicates that SDCT at 120 and 140 kV may have energy separation comparable to 100/140 kV and 80/140 kV dual‐kV imaging. The effects of IR on CNR and NPS require further investigation for SDCT.

Author YY and AD are Philips Healthcare employees.
TU‐EF‐210‐01: HIFU, Drug Delivery, and Immunotherapy
Authors: Ferrara K.
Published: June 2015

The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre‐clinical and clinical applications.

Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy

Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI‐guided HIFU

Elisa Konofagou: Real‐time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging

Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy

Learning Objectives:

Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy.

Understand potential targeted drug delivery clinical applications including pediatric oncology.

Understand the technical requirements for performing targeted drug delivery.

Understand how radiation‐force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy.

Understand the role of AAPM task groups in ultrasound imaging and therapies.

Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co‐founder of FUS Instruments Inc

Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE)

Farahani: In‐kind research support from Philips Healthcare
TU‐EF‐210‐02: MRg Hyperthermia
Authors: Chopra R.
Published: June 2015

The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre‐clinical and clinical applications.

Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy

Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI‐guided HIFU

Elisa Konofagou: Real‐time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging

Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy

Learning Objectives:

Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy.

Understand potential targeted drug delivery clinical applications including pediatric oncology.

Understand the technical requirements for performing targeted drug delivery.

Understand how radiation‐force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy.

Understand the role of AAPM task groups in ultrasound imaging and therapies.

Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co‐founder of FUS Instruments Inc

Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE)

Farahani: In‐kind research support from Philips Healthcare
TU‐PIS‐Exhibit Hall‐1: Tools for Collecting and Analyzing Patient Dose Index Information from Imaging Equipment
Authors: Supanich Mark , Wang J.
Published: June 2015

The current clinical standard of organ respiratory imaging, 4D‐CT, is fundamentally limited by poor soft‐tissue contrast and imaging dose. These limitations are potential barriers to beneficial “4D” radiotherapy methods which optimize the target and OAR dose‐volume considering breathing motion but rely on a robust motion characterization. Conversely, MRI imparts no known radiation risk and has excellent soft‐tissue contrast. MRI‐based motion management is therefore highly desirable and holds great promise to improve radiotherapy of moving cancers, particularly in the abdomen. Over the past decade, MRI techniques have improved significantly, making MR‐based motion management clinically feasible. For example, cine MRI has high temporal resolution up to 10 f/s and has been used to track and/or characterize tumor motion, study correlation between external and internal motions. New MR technologies, such as 4D‐MRI and MRI hybrid treatment machines (i.e. MR‐linac or MR‐Co60), have been recently developed. These technologies can lead to more accurate target volume determination and more precise radiation dose delivery via direct tumor gating or tracking. Despite all these promises, great challenges exist and the achievable clinical benefit of MRI‐based tumor motion management has yet to be fully explored, much less realized. In this proposal, we will review novel MR‐based motion management methods and technologies, the state‐of‐the‐art concerning MRI development and clinical application and the barriers to more widespread adoption.

Learning Objectives:

Discuss the need of MR‐based motion management for improving patient care in radiotherapy.

Understand MR techniques for motion imaging and tumor motion characterization.

Understand the current state of the art and future steps for clinical integration.

Henry Ford Health System holds research agreements with Philips Healthcare. Research sponsored in part by a Henry Ford Health System Internal Mentored Grant.
TU‐PIS‐Exhibit Hall‐4: How to implement a dose monitoring solution in the real world: a technical perspective
Authors: Massey S.
Published: June 2015

The current clinical standard of organ respiratory imaging, 4D‐CT, is fundamentally limited by poor soft‐tissue contrast and imaging dose. These limitations are potential barriers to beneficial “4D” radiotherapy methods which optimize the target and OAR dose‐volume considering breathing motion but rely on a robust motion characterization. Conversely, MRI imparts no known radiation risk and has excellent soft‐tissue contrast. MRI‐based motion management is therefore highly desirable and holds great promise to improve radiotherapy of moving cancers, particularly in the abdomen. Over the past decade, MRI techniques have improved significantly, making MR‐based motion management clinically feasible. For example, cine MRI has high temporal resolution up to 10 f/s and has been used to track and/or characterize tumor motion, study correlation between external and internal motions. New MR technologies, such as 4D‐MRI and MRI hybrid treatment machines (i.e. MR‐linac or MR‐Co60), have been recently developed. These technologies can lead to more accurate target volume determination and more precise radiation dose delivery via direct tumor gating or tracking. Despite all these promises, great challenges exist and the achievable clinical benefit of MRI‐based tumor motion management has yet to be fully explored, much less realized. In this proposal, we will review novel MR‐based motion management methods and technologies, the state‐of‐the‐art concerning MRI development and clinical application and the barriers to more widespread adoption.

Learning Objectives:

Discuss the need of MR‐based motion management for improving patient care in radiotherapy.

Understand MR techniques for motion imaging and tumor motion characterization.

Understand the current state of the art and future steps for clinical integration.

Henry Ford Health System holds research agreements with Philips Healthcare. Research sponsored in part by a Henry Ford Health System Internal Mentored Grant.
TU‐PIS‐Exhibit Hall‐5: Use of the Enterprise‐wide Dose Tracking Software Radimetrics In an Academic Medical System
Authors: Goode A.
Published: June 2015

The current clinical standard of organ respiratory imaging, 4D‐CT, is fundamentally limited by poor soft‐tissue contrast and imaging dose. These limitations are potential barriers to beneficial “4D” radiotherapy methods which optimize the target and OAR dose‐volume considering breathing motion but rely on a robust motion characterization. Conversely, MRI imparts no known radiation risk and has excellent soft‐tissue contrast. MRI‐based motion management is therefore highly desirable and holds great promise to improve radiotherapy of moving cancers, particularly in the abdomen. Over the past decade, MRI techniques have improved significantly, making MR‐based motion management clinically feasible. For example, cine MRI has high temporal resolution up to 10 f/s and has been used to track and/or characterize tumor motion, study correlation between external and internal motions. New MR technologies, such as 4D‐MRI and MRI hybrid treatment machines (i.e. MR‐linac or MR‐Co60), have been recently developed. These technologies can lead to more accurate target volume determination and more precise radiation dose delivery via direct tumor gating or tracking. Despite all these promises, great challenges exist and the achievable clinical benefit of MRI‐based tumor motion management has yet to be fully explored, much less realized. In this proposal, we will review novel MR‐based motion management methods and technologies, the state‐of‐the‐art concerning MRI development and clinical application and the barriers to more widespread adoption.

Learning Objectives:

Discuss the need of MR‐based motion management for improving patient care in radiotherapy.

Understand MR techniques for motion imaging and tumor motion characterization.

Understand the current state of the art and future steps for clinical integration.

Henry Ford Health System holds research agreements with Philips Healthcare. Research sponsored in part by a Henry Ford Health System Internal Mentored Grant.
TU‐F‐BRB‐00: MRI‐Based Motion Management for RT
Authors: Cai Jing
Published: June 2015

The current clinical standard of organ respiratory imaging, 4D‐CT, is fundamentally limited by poor soft‐tissue contrast and imaging dose. These limitations are potential barriers to beneficial “4D” radiotherapy methods which optimize the target and OAR dose‐volume considering breathing motion but rely on a robust motion characterization. Conversely, MRI imparts no known radiation risk and has excellent soft‐tissue contrast. MRI‐based motion management is therefore highly desirable and holds great promise to improve radiotherapy of moving cancers, particularly in the abdomen. Over the past decade, MRI techniques have improved significantly, making MR‐based motion management clinically feasible. For example, cine MRI has high temporal resolution up to 10 f/s and has been used to track and/or characterize tumor motion, study correlation between external and internal motions. New MR technologies, such as 4D‐MRI and MRI hybrid treatment machines (i.e. MR‐linac or MR‐Co60), have been recently developed. These technologies can lead to more accurate target volume determination and more precise radiation dose delivery via direct tumor gating or tracking. Despite all these promises, great challenges exist and the achievable clinical benefit of MRI‐based tumor motion management has yet to be fully explored, much less realized. In this proposal, we will review novel MR‐based motion management methods and technologies, the state‐of‐the‐art concerning MRI development and clinical application and the barriers to more widespread adoption.

Learning Objectives:

Discuss the need of MR‐based motion management for improving patient care in radiotherapy.

Understand MR techniques for motion imaging and tumor motion characterization.

Understand the current state of the art and future steps for clinical integration.

Henry Ford Health System holds research agreements with Philips Healthcare. Research sponsored in part by a Henry Ford Health System Internal Mentored Grant.
TU‐F‐BRB‐02: Motion Artifacts and Suppression in MRI
Authors: Zhong X.
Published: June 2015

The current clinical standard of organ respiratory imaging, 4D‐CT, is fundamentally limited by poor soft‐tissue contrast and imaging dose. These limitations are potential barriers to beneficial “4D” radiotherapy methods which optimize the target and OAR dose‐volume considering breathing motion but rely on a robust motion characterization. Conversely, MRI imparts no known radiation risk and has excellent soft‐tissue contrast. MRI‐based motion management is therefore highly desirable and holds great promise to improve radiotherapy of moving cancers, particularly in the abdomen. Over the past decade, MRI techniques have improved significantly, making MR‐based motion management clinically feasible. For example, cine MRI has high temporal resolution up to 10 f/s and has been used to track and/or characterize tumor motion, study correlation between external and internal motions. New MR technologies, such as 4D‐MRI and MRI hybrid treatment machines (i.e. MR‐linac or MR‐Co60), have been recently developed. These technologies can lead to more accurate target volume determination and more precise radiation dose delivery via direct tumor gating or tracking. Despite all these promises, great challenges exist and the achievable clinical benefit of MRI‐based tumor motion management has yet to be fully explored, much less realized. In this proposal, we will review novel MR‐based motion management methods and technologies, the state‐of‐the‐art concerning MRI development and clinical application and the barriers to more widespread adoption.

Learning Objectives:

Discuss the need of MR‐based motion management for improving patient care in radiotherapy.

Understand MR techniques for motion imaging and tumor motion characterization.

Understand the current state of the art and future steps for clinical integration.

Henry Ford Health System holds research agreements with Philips Healthcare. Research sponsored in part by a Henry Ford Health System Internal Mentored Grant.
TU‐G‐304‐02: Physics of the AAPM
Authors: Keener J.
Published: June 2015

As a new member of AAPM, it's easy to feel overwhelmed by the size and complexity of the association and to be unaware of the benefits and opportunities available to members. At this year's AAPM Annual Meeting in Anaheim, we will host a New Member Symposium where you can learn more about the organization, member resources, opportunities to get involved, and about topics of particular interest to new professionals. We encourage you to take advantage of this great opportunity to learn valuable information and to grow your professional network.

Following an introduction from Dr. John Boone, AAPM President; Justin Keener, Chair of the New Professional Subcommittee, will speak on, “Physics of the AAPM.” Next will be Dr. George Sherouse sharing invaluable information in his talk, “Things You Won't Be Able to Say Somebody Should've Told You.”

Registered attendees will receive a raffle ticket. Enter to win a complimentary registration for the 2016 Annual Meeting in Washington, DC!

In addition, all new members who register for the Symposium will receive a drink ticket, good for one complimentary soda or beer served after the New Member Symposium during the social with Committee Chairs from 4 AAPM Councils: Science, Education, Professional and Administrative.

Get your picture taken!!! There will be a photographer there to take pictures for your profile in the AAPM directory.

The New Member Symposium is a (free) ticket option when you register online for the Annual Meeting. We hope that you will plan to attend.
TU‐F‐201‐00: Radiochromic Film Dosimetry Update
Authors: Chiu‐Tsao Sou‐Tung
Published: June 2015

Since the introduction of radiochromic films (RCF) for radiation dosimetry, the scope of RCF dosimetry has expanded steadily to include many medical applications, such as radiation therapy and diagnostic radiology. The AAPM Task Group (TG) 55 published a report on the recommendations for RCF dosimetry in 1998. As the technology is advancing rapidly, and its routine clinical use is expanding, TG 235 has been formed to provide an update to TG‐55 on radiochromic film dosimetry. RCF dosimetry applications in clinical radiotherapy have become even more widespread, expanding from primarily brachytherapy and radiosurgery applications, and gravitating towards (but not limited to) external beam therapy (photon, electron and protons), such as quality assurance for IMRT, VMAT, Tomotherapy, SRS/SRT, and SBRT. In addition, RCF applications now extend to measurements of radiation dose in particle beams and patients undergoing medical exams, especially fluoroscopically guided interventional procedures and CT. The densitometers/scanners used for RCF dosimetry have also evolved from the He‐Ne laser scanner to CCD‐based scanners, including roller‐based scanner, light box‐based digital camera, and flatbed color scanner. More recently, multichannel RCF dosimetry introduced a new paradigm for external beam dose QA for its high accuracy and efficiency. This course covers in detail the recent advancements in RCF dosimetry.

Learning Objectives:

Introduce the paradigm shift on multichannel film dosimetry

Outline the procedures to achieve accurate dosimetry with a RCF dosimetry system

Provide comprehensive guidelines on RCF dosimetry for various clinical applications

One of the speakers has a research agreement from Ashland Inc., the manufacturer of Gafchromic film.