bluuebunny/crossref_metadata_2025_split huggingface dataset:
TU‐H‐CAMPUS‐JeP2‐05: Can Automatic Delineation of Cardiac Substructures On Noncontrast CT Be Used for Cardiac Toxicity Analysis?
Authors: Luo Y , Liao Z , Jiang W , Gomez D , Williamson R , Court L , Yang J 
Published: July 2016

Purpose:To evaluate the feasibility of using an automatic segmentation tool to delineate cardiac substructures from computed tomography (CT) images for cardiac toxicity analysis for non‐small cell lung cancer (NSCLC) patients after radiotherapy.Methods:A multi‐atlas segmentation tool developed in‐house was used to delineate eleven cardiac substructures including the whole heart, four heart chambers, and six greater vessels automatically from the averaged 4DCT planning images for 49 NSCLC patients. The automatic segmented contours were edited appropriately by two experienced radiation oncologists. The modified contours were compared with the auto‐segmented contours using Dice similarity coefficient (DSC) and mean surface distance (MSD) to evaluate how much modification was needed. In addition, the dose volume histogram (DVH) of the modified contours were compared with that of the auto‐segmented contours to evaluate the dosimetric difference between modified and auto‐segmented contours.Results:Of the eleven structures, the averaged DSC values ranged from 0.73 ± 0.08 to 0.95 ± 0.04 and the averaged MSD values ranged from 1.3 ± 0.6 mm to 2.9 ± 5.1mm for the 49 patients. Overall, the modification is small. The pulmonary vein (PV) and the inferior vena cava required the most modifications. The V30 (volume receiving 30 Gy or above) for the whole heart and the mean dose to the whole heart and four heart chambers did not show statistically significant difference between modified and auto‐segmented contours. The maximum dose to the greater vessels did not show statistically significant difference except for the PV.Conclusion:The automatic segmentation of the cardiac substructures did not require substantial modification. The dosimetric evaluation showed no statistically significant difference between auto‐segmented and modified contours except for the PV, which suggests that auto‐segmented contours for the cardiac dose response study are feasible in the clinical practice with a minor modification to the PV vessel.
TU‐H‐CAMPUS‐TeP2‐02: FLASH Irradiation Improves the Therapeutic Index Following GI Tract Irradiation
Authors: Schueler E , Trovati S , King G , Lartey F , Rafat M , Loo B , Maxim P 
Published: July 2016

Purpose:To investigate and characterize the radiobiological effectiveness of very high dose rate radiotherapy (FLASH) compared to conventional irradiation in an in vivo model.Methods:The gastrointestinal (GI) tract of C57BL/6 mice were irradiated with doses ranging between 10 and 18 Gy using a custom stereotactic jig. A Varian Clinac 21EX was modified to allow dose rates ranging from 0.05 to 240 Gy/s at the position of the mirror. With the gantry at 180 degrees, the jig holding the individual animals was placed above the mirror to take advantage of the reduced source to target distance. Mice were irradiated with 20MeV electrons. Following irradiation, the mice were monitored twice daily for morbidity and daily for weight changes.Results:Mice irradiated with FLASH irradiation had lower weight loss compared to the mice receiving conventional irradiation. Following FLASH irradiation, a maximum weight loss of ∼20% was observed at day 6 with subsequent recovery, while following conventional irradiation, higher weight losses was observed with fewer instances of recovery. Concerning survival, all mice in the conventionally irradiated groups had a 100% mortality in the range of 15.5–18 Gy, while the mice irradiated with FLASH irradiation had a 100% survival in the same range.Conclusion:These results have demonstrated proof of principle that FLASH irradiations have a dramatic impact on the overall survival of mice following GI tract irradiations. If the increase in the therapeutic window can be validated and understood, this would revolutionize the field of radiation oncology and lead to increased cure rates with reduced side effects following treatment, resulting in increased quality of life for cancer survivors.Funding: DoD, Award#:W81XWH‐14‐1‐0014, Weston Havens Foundation, Bio‐X (Stanford University), the Office of the Dean of the Medical School, the Office of the Provost (Stanford University), and the Swedish Childhood Cancer Foundation; BL and PM are founders of TibaRay,Inc.; BL and PM have received research grants from Varian and RaySearch Laboratory.
TU‐H‐CAMPUS‐IeP3‐02: Neurovascular 4D Parametric Imaging Using Co‐Registration of Biplane DSA Sequences with 3D Vascular Geometry Obtained From Cone Beam CT
Authors: Balasubramoniam A , Bednarek D , Rudin S , Ionita C 
Published: July 2016

Purpose:To create 4D parametric images using biplane Digital Subtraction Angiography (DSA) sequences co‐registered with the 3D vascular geometry obtained from Cone Beam‐CT (CBCT).Methods:We investigated a method to derive multiple 4D Parametric Imaging (PI) maps using only one CBCT acquisition. During this procedure a 3D‐DSA geometry is stored and used subsequently for all 4D images. Each time a biplane DSA is acquired, we calculate 2D parametric maps of Bolus Arrival Time (BAT), Mean Transit Time (MTT) and Time to Peak (TTP). Arterial segments which are nearly parallel with one of the biplane imaging planes in the 2D parametric maps are co‐registered with the 3D geometry. The values in the remaining vascular network are found using spline interpolation since the points chosen for co‐registration on the vasculature are discrete and remaining regions need to be interpolated. To evaluate the method we used a patient CT volume data set for 3D printing a neurovascular phantom containing a complete Circle of Willis. We connected the phantom to a flow loop with a peristaltic pump, simulating physiological flow conditions. Contrast media was injected with an automatic injector at 10 ml/sec. Images were acquired with a Toshiba Infinix C‐arm and 4D parametric image maps of the vasculature were calculated.Results:4D BAT, MTT, and TTP parametric image maps of the Circle of Willis were derived. We generated color‐coded 3D geometries which avoided artifacts due to vessel overlap or foreshortening in the projection direction.Conclusion:The software was tested successfully and multiple 4D parametric images were obtained from biplane DSA sequences without the need to acquire additional 3D‐DSA runs. This can benefit the patient by reducing the contrast media and the radiation dose normally associated with these procedures.Partial support from NIH Grant R01‐EB002873 and Toshiba Medical Systems Corp.
TU‐H‐CAMPUS‐IeP3‐04: Evaluation of Changes in Quantitative Ultrasound Parameters During Prostate Radiotherapy
Authors: Najafi M , El Kaffas A , Han B , Cooper D , Hancock S , Hristov D 
Published: July 2016

Purpose:Clarity Autoscan ultrasound monitoring system allows acquisition of raw radiofrequency (RF) ultrasound data prior and during radiotherapy. This enables the computation of 3D Quantitative Ultrasound (QUS) tissue parametric maps from. We aim to evaluate whether QUS parameters undergo changes with radiotherapy and thus potentially be used as early predictors and/or markers of treatment response in prostate cancer patients.Methods:In‐vivo evaluation was performed under IRB protocol to allow data collection in prostate patients treated with VMAT whereby prostate was imaged through the acoustic window of the perineum. QUS spectroscopy analysis was carried out by computing a tissue power spectrum normalized to the power spectrum obtained from a quartz to remove system transfer function effects. A ROI was selected within the 3D image volume of the prostate. Because longitudinal registration was optimal, the same features could be used to select ROIs at roughly the same location in images acquired on different days. Parametric maps were generated within the rectangular ROIs with window sizes that were approximately 8 times the wavelength of the ultrasound. The mid‐band fit (MBF), spectral slope (SS) and spectral intercept (SI) QUS parameters were computed for each window within the ROI and displayed as parametric maps. Quantitative parameters were obtained by averaging each of the spectral parameters over the whole ROI.Results:Data was acquired for over 21 treatment fractions. Preliminary results show changes in the parametric maps. MBF values decreased from −33.9 dB to −38.7 dB from pre‐treatment to the last day of treatment. The spectral slope increased from −1.1 a.u. to −0.5 a.u., and spectral intercept decreased from −28.2 dB to −36.3 dB over the 21 treatment regimen.Conclusion:QUS parametric maps change over the course of treatment which warrants further investigation in their potential use for treatment planning and predicting treatment outcomes.Research was supported by Elekta.
TU‐H‐CAMPUS‐IeP3‐05: Computer Aided Diagnosis Employing Automatically Segmented Color‐Specific Regions in Ultrasound Shear Wave Elastography for the Assessment of Chronic Liver Disease
Authors: Gatos I. , Tsantis S. , Kagadis G.C. 
Published: July 2016

Purpose:To assess the role of an automated Computer Aided Diagnosis (CAD) system in differentiation of Healthy Subjects to Chronic Liver Disease (CLD) Patients in terms of liver fibrosis (F0‐F4), using Ultrasound Shear Wave Elastography (SWE).Methods:Clinical Dataset consisted of 125 subjects, 55 Healthy (F0) whom condition was validated with Normal Biochemical Markers and clear Clinical History, and 70 with CLD (F1‐F4) whom condition was validated with Liver Biopsy. For each subject an SWE examination on their liver right lobe was performed using Supersonic Imagine's Aixplorer ultrasound system, and an SC6‐1 transducer. The examination was performed using preset default settings for Abdomen/Liver, and according to literature's suggested guidelines. An SWE image was then acquired, and a separation of the colored areas from the grayscale ones was performed. An RGB‐to‐Stiffness algorithm was consequently applied on the resulting image (Stiffness Box), using the nbuilt‐in colormap, to replace RGB values to Stiffness values. A segmentation procedure was employed using thresholds that segment the image to 5 stiffness range clusters (0–6, 6–12, 12–18, 18–24, and 24–30 kPa), and extract 7 features from each cluster (Mean, Median, Standard Deviation, Sample Kurtosis, 10th Percentile, 90th Percentile, and Cluster's Pixel Percentage on the Stiffness Box) deriving 35 features for each SWE image. The computed feature set was then fed to a designed SVM classifier. SVM‐model evaluation was performed by means of exhaustive search, and leave‐one‐out methods.Results:Maximum classification accuracy (85.6%) in distinguishing Healthy from chronic liver disease patients was obtained employing three features (Blue mean and Cyan median values, and Red maximum pixel number) with sensitivity and specificity values of 91.9% and 79.3% respectively.Conclusion:The proposed CAD system accurately differentiates Healthy to CLD patients assisting in evaluating important factors for performing SWE examination, enriching its guidelines, and aiding clinicians in a more accurate diagnosis.
TU‐H‐CAMPUS‐JeP3‐04: Factors Predicting a Need for Treatment Replanning with Proton Radiotherapy for Lung Cancer
Authors: Teng C , Janssens G , Ainsley C , Teo B , Valdes G , Burgdorf B , Berman A , Levin W , Xiao Y , Lin L , Gabriel P , Simone C , Solberg T 
Published: July 2016

Purpose:Proton dose distribution is sensitive to tumor regression and tissue and normal anatomy changes. Replanning is sometimes necessary during treatment to ensure continue tumor coverage or avoid overtreatment of organs at risk (OARs). We investigated action thresholds for replanning and identified both dosimetric and non‐dosimetric metrics that would predict a need for replan.Methods:All consecutive lung cancer patients (n = 188) who received definitive proton radiotherapy and had more than two evaluation CT scans at the Roberts Proton Therapy Center (Philadelphia, USA) from 2011 to 2015 were included in this study. The cohort included a variety of tumor sizes, locations, histology, beam angles, as well as radiation‐induced tumor and lung change. Dosimetric changes during therapy were characterized by changes in the dose volume distribution of PTV, ITV, and OARs (heart, cord, esophagus, brachial plexus and lungs). Tumor and lung change were characterized by changes in sizes, and in the distribution of Hounsfield numbers and water equivalent thickness (WET) along the beam path. We applied machine learning tools to identify both dosimetric and non‐dosimetric metrics that predicted a replan.Results:Preliminary data showed that clinical indicators (n = 54) were highly correlated; thus, a simple indicator may be derived to guide the action threshold for replanning. Additionally, tumor regression alone could not predict dosimetric changes in OARs; it required further information about beam angles and tumor locations.Conclusion:Both dosimetric and non‐dosimetric factors are predictive of the need for replanning during proton treatment.
TU‐H‐CAMPUS‐TeP3‐05: Evaluation of the Microscopic Dose Enhancement in the Nanoparticle‐Enhanced Auger Therapy
Authors: Sung W , Jung S , Ye S 
Published: July 2016

Purpose:The aim of this study is to apply Monte Carlo simulations to investigate the nanoparticle dose enhancement for Auger therapy.Methods:Two nanoparticle fabrications were considered: nanoshell and nanosphere. In the first step, a single nanoparticle was irradiated with Auger emitters. The electrons were scored in a phase space at the outer surface of the nanoparticle with Geant4‐Penelope. In the second step, the previously recorded phase space was used as a source and placed at the center of a cell‐size water phantom. The nanoscale dose was evaluated in water around the nanoparticle with Geant4‐DNA. The dose enhancement factor (DEF) is defined as the ratio of doses with and without nanoparticles. The nanoparticles were replaced by corresponding water nanoparticle with the same size and volume source which represents typical situation of Auger emitters without nanoparticle. Various sizes/materials of nanoparticles and isotopes were considered.Results:Nanoshell ‐ Microscopic dose was increased up to 130% at 20 – 100 nm distances from the surface of Au‐125I nanoshell. However, dose at less than 20 nm distance was reduced due to absorbed low energy electrons in gold nanoshell. The amounts and regions of the dose enhancement were dependent on nanoshell size, materials, and isotopes. Nanosphere ‐ The increased amounts of electrons up to 300% and reduced average energy with nanosphere were observed compared with water nanoparticle. We observed localized dose enhancement (up to a factor 3.6) in the immediate vicinity (< 50 nm) of Au‐125 I nanosphere. The dose enhancement patterns vary according to nanosphere sizes and isotopes.Conclusion:We conclude that Auger therapy with nanoparticles can lead to change of electron energy spectrum and dose enhancements at certain range. The dose enhancement patterns vary according to nanoparticle sizes, materials, and isotopes.This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP: Ministry of Science, ICT and Future Planning) (No. NRF‐2013M2B2B1075776)
WE‐AB‐204‐01: Welcome
Authors: Curran B. 
Published: July 2016

Many efforts have been made to increase diversity in the science workforce. In order for us to be competitive in innovation and ingenuity we need to reach out to any source of intellectual talent. Having greater diversity can only increase the creativity in medical physics. In order for students to succeed academically they need role models and mentors with whom they can identify. Literature has shown that racial and ethnic diversity has both direct and indirect positive effects on the educational outcomes, career advancement and motivation of students. Diversity not only focuses on race, ethnicity and gender, but it can also include socioeconomic status, sexual orientation and more. Underrepresented populations have had low numbers over the years not only in medical physics but also in the sciences in general. With the rapidly changing face of our country we need to address how we attract and train the next generation of scientists to stay competitive. It is necessary to examine the role that diversity and inclusion play in the long term goals of institutions, workplaces and classrooms. To increase innovation we must engage people from all walks of life with different perspectives and life experiences to solve the problems that we will face. Diversity should be viewed as a strategy to achieve our goals instead of acts of good citizenship. Many of today's businesses and corporations have discovered that embracing diversity prepares future leaders in today's global market.This lecture will provide insight to how differences within our society can drive innovation. We will provide an overview of the role diversity and inclusion plays in the clinic, education and research to develop the future workforce in medical physics.

Learning Objectives:
Understanding the role diversity and inclusion plays in medical physics.
The importance of developing education and research strategies for a global workforce.
How to develop a roadmap to diversity excellence within AAPM.
WE‐AB‐204‐04: D&I in Physics
Authors: Hammer P. 
Published: July 2016

Many efforts have been made to increase diversity in the science workforce. In order for us to be competitive in innovation and ingenuity we need to reach out to any source of intellectual talent. Having greater diversity can only increase the creativity in medical physics. In order for students to succeed academically they need role models and mentors with whom they can identify. Literature has shown that racial and ethnic diversity has both direct and indirect positive effects on the educational outcomes, career advancement and motivation of students. Diversity not only focuses on race, ethnicity and gender, but it can also include socioeconomic status, sexual orientation and more. Underrepresented populations have had low numbers over the years not only in medical physics but also in the sciences in general. With the rapidly changing face of our country we need to address how we attract and train the next generation of scientists to stay competitive. It is necessary to examine the role that diversity and inclusion play in the long term goals of institutions, workplaces and classrooms. To increase innovation we must engage people from all walks of life with different perspectives and life experiences to solve the problems that we will face. Diversity should be viewed as a strategy to achieve our goals instead of acts of good citizenship. Many of today's businesses and corporations have discovered that embracing diversity prepares future leaders in today's global market.This lecture will provide insight to how differences within our society can drive innovation. We will provide an overview of the role diversity and inclusion plays in the clinic, education and research to develop the future workforce in medical physics.

Learning Objectives:
Understanding the role diversity and inclusion plays in medical physics.
The importance of developing education and research strategies for a global workforce.
How to develop a roadmap to diversity excellence within AAPM.
WE‐AB‐204‐05: D&I in NIH ‐ Funding/Research
Authors: Chew D. 
Published: July 2016

Many efforts have been made to increase diversity in the science workforce. In order for us to be competitive in innovation and ingenuity we need to reach out to any source of intellectual talent. Having greater diversity can only increase the creativity in medical physics. In order for students to succeed academically they need role models and mentors with whom they can identify. Literature has shown that racial and ethnic diversity has both direct and indirect positive effects on the educational outcomes, career advancement and motivation of students. Diversity not only focuses on race, ethnicity and gender, but it can also include socioeconomic status, sexual orientation and more. Underrepresented populations have had low numbers over the years not only in medical physics but also in the sciences in general. With the rapidly changing face of our country we need to address how we attract and train the next generation of scientists to stay competitive. It is necessary to examine the role that diversity and inclusion play in the long term goals of institutions, workplaces and classrooms. To increase innovation we must engage people from all walks of life with different perspectives and life experiences to solve the problems that we will face. Diversity should be viewed as a strategy to achieve our goals instead of acts of good citizenship. Many of today's businesses and corporations have discovered that embracing diversity prepares future leaders in today's global market.This lecture will provide insight to how differences within our society can drive innovation. We will provide an overview of the role diversity and inclusion plays in the clinic, education and research to develop the future workforce in medical physics.

Learning Objectives:
Understanding the role diversity and inclusion plays in medical physics.
The importance of developing education and research strategies for a global workforce.
How to develop a roadmap to diversity excellence within AAPM.
WE‐AB‐204‐06: D&I in Global Health
Authors: Ngoma T. 
Published: July 2016

Many efforts have been made to increase diversity in the science workforce. In order for us to be competitive in innovation and ingenuity we need to reach out to any source of intellectual talent. Having greater diversity can only increase the creativity in medical physics. In order for students to succeed academically they need role models and mentors with whom they can identify. Literature has shown that racial and ethnic diversity has both direct and indirect positive effects on the educational outcomes, career advancement and motivation of students. Diversity not only focuses on race, ethnicity and gender, but it can also include socioeconomic status, sexual orientation and more. Underrepresented populations have had low numbers over the years not only in medical physics but also in the sciences in general. With the rapidly changing face of our country we need to address how we attract and train the next generation of scientists to stay competitive. It is necessary to examine the role that diversity and inclusion play in the long term goals of institutions, workplaces and classrooms. To increase innovation we must engage people from all walks of life with different perspectives and life experiences to solve the problems that we will face. Diversity should be viewed as a strategy to achieve our goals instead of acts of good citizenship. Many of today's businesses and corporations have discovered that embracing diversity prepares future leaders in today's global market.This lecture will provide insight to how differences within our society can drive innovation. We will provide an overview of the role diversity and inclusion plays in the clinic, education and research to develop the future workforce in medical physics.

Learning Objectives:
Understanding the role diversity and inclusion plays in medical physics.
The importance of developing education and research strategies for a global workforce.
How to develop a roadmap to diversity excellence within AAPM.