Radiation Medicine Commons^™

Efficacy Of Scalp-Sparing Volumetric-Modulated Arc Therapy Approach In Reducing Scalp Radiation Dose For Patients With Glioblastoma: A Cross-Sectional Study, Muneeb Khan Niazi, Olga Russial, Louis Cappelli, Ryan Miller, Yingxuan Chen, Yelena Vakhnenko, Haisong Lui, Wenyin Shi

Department of Radiation Oncology Faculty Papers

BACKGROUND: Radiation is integral to the treatment of glioblastoma (GBM). However, radiation-induced scalp toxicity can negatively impact patients' quality of life. Volumetric modulated arc therapy (VMAT) optimizes the dose to organs at risk (OARs). We hypothesize that a scalp-sparing VMAT (SSV) approach can significantly reduce undesirable doses to the scalp without compromising the target dose.

METHODS: This is a retrospective cross-sectional study of GBM patients who originally received radiation with non-SSV. We contoured the scalp as a 5 mm rind-like structure beneath the skin above the level of the foramen magnum. We replanned our patients using SSV techniques. We compared …

Inducing Accelerated Lung Toxicity In Mice Using A Partial Arc Sbrt Technique, Andrew Gerry, Charita Kunta, Noelle Francois, Tiziana Deangelis, Anuradha Shastri, Nicole Simone, Reza Taleei

Department of Radiation Oncology Posters

Background

• Radiation-induced pulmonary fibrosis (RIPF) is a frequent outcome of thoracic radiation therapy, constraining safe tumor radiation dosage. Various animal models, such as mice, rats, and pigs, have been devised to study RIPF
• Current methods for inducing lung fibrosis in mice involve whole lung irradiation with doses between 2-20 Gy. These methods used fixed anterior and posterior (AP/PA) x-ray beams at 0º and 180º with analysis typically commencing 24 to 52 weeks post-radiation
• Current methods are unrepresentative of modern radiation therapy techniques and are limited by the associated long latency of RIPF

Immunotherapy Targeting Different Immune Compartments In Combination With Radiation Therapy Induces Regression Of Resistant Tumors, Nils-Petter Rudqvist, Maud Charpentier, Claire Lhuillier, Erik Wennerberg, Sheila Spada, Caroline Sheridan, Xi Kathy Zhou, Tuo Zhang, Silvia C Formenti, Jennifer S Sims, Alicia Alonso, Sandra Demaria

Faculty, Staff and Student Publications

Radiation therapy (RT) increases tumor response to CTLA-4 inhibition (CTLA4i) in mice and in some patients, yet deep responses are rare. To identify rational combinations of immunotherapy to improve responses we use models of triple negative breast cancer highly resistant to immunotherapy in female mice. We find that CTLA4i promotes the expansion of CD4+ T helper cells, whereas RT enhances T cell clonality and enriches for CD8+ T cells with an exhausted phenotype. Combination therapy decreases regulatory CD4+ T cells and increases effector memory, early activation and precursor exhausted CD8+ T cells. A combined gene signature comprising these three CD8+ …

Advances In The Radiological Evaluation Of And Theranostics For Glioblastoma, Grayson W Hooper, Shehbaz Ansari, Jason M Johnson, Daniel T Ginat

Faculty, Staff and Student Publications

Imaging is essential for evaluating patients with glioblastoma. Traditionally a multimodality undertaking, CT, including CT cerebral blood profusion, PET/CT with traditional fluorine-18 fluorodeoxyglucose (18F-FDG), and MRI have been the mainstays for diagnosis and post-therapeutic assessment. However, recent advances in these modalities, in league with the emerging fields of radiomics and theranostics, may prove helpful in improving diagnostic accuracy and treating the disease.

Dosimetric Evaluation Of Left-Sided Chest Wall Vmat Treatment With And Without Jaw Tracking; Dose Comparison Of Left Anterior Descending Artery Versus Heart Mean Dose, Jacqueline J. Emus

Masters Projects

Radiation therapy has significantly improved breast cancer survival rates; however, it can still lead to long-term side effects, particularly affecting the heart. Left-side breast cancer patients face higher risks due to the proximity of the heart to the treatment area. To mitigate cardiac toxicity, various strategies, including jaw tracking and Volumetric Modulated Arc Therapy (VMAT), have been proposed. This study investigates the dosimetric impact of VMAT plans with and without jaw tracking on the left anterior descending artery (LAD) dose and heart mean dose in post-mastectomy breast cancer patients. Ten patients previously treated with VMAT were evaluated, and the results …

Innate Immune System In The Context Of Radiation Therapy For Cancer, Boopathi Ettickan, Robert Den, Chellappagounder Thangavel

Department of Radiation Oncology Faculty Papers

Radiation therapy (RT) remains an integral component of modern oncology care, with most cancer patients receiving radiation as a part of their treatment plan. The main goal of ionizing RT is to control the local tumor burden by inducing DNA damage and apoptosis within the tumor cells. The advancement in RT, including intensity-modulated RT (IMRT), stereotactic body RT (SBRT), image-guided RT, and proton therapy, have increased the efficacy of RT, equipping clinicians with techniques to ensure precise and safe administration of radiation doses to tumor cells. In this review, we present the technological advancement in various types of RT methods …

The Development Of Artificial Intelligence-Based To Ols For Expert Peer Review Of Radiotherapy Treatment Plans, Mary Gronberg

Dissertations and Theses (Open Access)

Creating a patient-specific radiation treatment plan is a time-consuming and operator-dependent manual process. The treatment planner adjusts the planning parameters in a trial-and-error fashion in an effort to balance the competing clinical objectives of tumor coverage and normal tissue sparing. Often, a plan is selected because it meets basic organ at risk dose thresholds for severe toxicity; however, it is evident that a plan with a decreased risk of normal tissue complication probability could be achieved. This discrepancy between “acceptable” and “best possible” plan is magnified if either the physician or treatment planner lacks focal expertise in the disease site. …

Auto-Segmentation In Pancreatic And Liver Radiation Therapy, Cenji Yu

Dissertations and Theses (Open Access)

Background

Gastrointestinal cancers exhibit a high mortality rate compared to other cancer types. Among these, pancreatic cancer ranks as the fourth leading cause of cancer-related deaths worldwide. The five-year survival rate remains alarmingly low at a mere 9%. Hepatocellular carcinoma (HCC), another aggressive form of cancer, is rapidly becoming the primary cause of cancer-related deaths in the United States. The treatment of both liver cancer and pancreatic cancer heavily relies on a multidisciplinary approach. Innovative treatment strategies involving dose-escalated regimens, such as stereotactic body radiation therapy (SBRT), are emerging as an important pillar of the management of liver and pancreatic …

Risk And Risk Factors For Colorectal Subsequent Malignancies In Survivors Of Childhood Cancer: A Report From The Childhood Cancer Survivor Study, Constance A. Owens

Dissertations and Theses (Open Access)

Survivors of childhood cancer are at risk for colorectal subsequent malignant neoplasms (SMNs); notably, these cancers are amenable to screening. To identify at-risk survivors that may benefit from early screening, descriptive and risk factor analyses were performed to ascertain risk factors for colorectal SMN in childhood cancer survivors. In particular, we explored detailed radiation therapy (RT) data – colorectal and substructure dose-volume metrics – as risk factors for colorectal SMN risk; metrics that have yet to be thoroughly investigated. We developed a novel population-based anatomical colorectal model with substructures for RT dosimetry in late effects studies of childhood cancer survivors; …

Gwas-Identified Telomere Length Associated Genetic Variants Predict Risk Of Recurrence Of Hpv-Positive Oropharyngeal Cancer After Definitive Radiotherapy, Peng Sun, Peng Wei, Hongliang Liu, Jia Wu, Neil D Gross, Andrew G Sikora, Qingyi Wei, Sanjay Shete, Mark E Zafereo, Jisheng Liu, Guojun Li

Faculty, Staff and Student Publications

Background: Lymphocyte telomere length (LTL)-related genetic variants may modulate LTL and affect recurrence of squamous cell carcinoma of the oropharynx (SCCOP).

Methods: A total of 1013 patients with incident SCCOP were recruited and genotyped for 16 genome-wide association study (GWAS)-identified TL-related polymorphisms. Of these patients, 489 had tumour HPV16 status determination. Univariate and multivariate analyses were performed to evaluate associations.

Findings: Of the 16 TL-related polymorphisms, four were significantly associated with LTL: rs1920116, rs3027234, rs6772228, and rs11125529, and the patients with putatively favourable genotypes had approximately 1.5-3 times the likelihood of shorter LTL compared with patients with the corresponding risk …

Predicting Severity Of Radiation Induced Lymphopenia In Individual Proton Therapy Patients For Varying Dose Rate And Fractionation Using Dynamic 4-Dimensional Blood Flow Simulations, Lucas Mccullum, Jungwook Shin, Stella Xing, Chris Beekman, Jan Schuemann, Theodore Hong, Dan Duda, Radhe Mohan, Steven H Lin, Camilo M Correa-Alfonso, Sean Domal, Julia Withrow, Wesley Bolch, Harald Paganetti, Clemens Grassberger

Faculty, Staff and Student Publications

PURPOSE: Radiation-induced lymphopenia has gained attention recently as the result of its correlation with survival in a range of indications, particularly when combining radiation therapy (RT) with immunotherapy. The purpose of this study is to use a dynamic blood circulation model combined with observed lymphocyte depletion in patients to derive the in vivo radiosensitivity of circulating lymphocytes and study the effect of RT delivery parameters.

METHODS AND MATERIALS: We assembled a cohort of 17 patients with hepatocellular carcinoma treated with proton RT alone in 15 fractions (fx) using conventional dose rates (beam-on time [BOT], 120 seconds) for whom weekly absolute …

Multi-Parametric Mri For Radiotherapy Simulation, Tian Li, Jihong Wang, Yingli Yang, Carri K Glide-Hurst, Ning Wen, Jing Cai

Faculty, Staff and Student Publications

Magnetic resonance imaging (MRI) has become an important imaging modality in the field of radiotherapy (RT) in the past decade, especially with the development of various novel MRI and image-guidance techniques. In this review article, we will describe recent developments and discuss the applications of multi-parametric MRI (mpMRI) in RT simulation. In this review, mpMRI refers to a general and loose definition which includes various multi-contrast MRI techniques. Specifically, we will focus on the implementation, challenges, and future directions of mpMRI techniques for RT simulation.

A Quantitative Dosimetric Comparison Of Dibh Vmat And Static-Imrt Apbi Treatments: Evaluating Large Left Sided Lumpectomy Cavities Located Near The Chest Wall, Christopher Jordan Clifton

Masters Projects

Abstract

Introduction

The main purpose of this study was to determine whether there was a significant difference between the dose distributions when comparing static-IMRT and VMAT plans for patients with large left sided lumpectomy cavities located near the chest wall while utilizing DIBH. Thorough planning and statistical analysis was performed to determine whether there was a clear advantage for either treatment technique to better benefit patient outcomes.

Methods

Ten female patients with large left sided lumpectomy cavities were selected to be retrospectively planned using both static-IMRT and VMAT plans. Each patient fell within the ASTRO eligibility criteria for APBI treatments. …

A Dosimetric Comparison Of Jaw Tracking Versus Non-Jaw Tracking Using 6mv Vmat Treatment Beams In Prostate Patients With Involved Lymph Nodes, Rebecca Todd

Masters Projects

Introduction:

Jaw tracking is the process of the collimator jaws dynamically following the multileaf collimators during modulated therapy. Jaw tracking can be used throughout the dosimetry treatment planning process for IMRT and VMAT treatment plans. It can reduce a patient’s OAR dose by reducing low dose spillage from MLC interleaf leakage. This study aims to investigate if jaw tracking reduces OAR dose while maintaining PTV coverage in prostate patients with involved lymph nodes using 6MV VMAT treatment planning technique.

Methods:

This is a quantitative study of 10 patients. For each patient, two plans were created, one plan using a non-jaw …

Longitudinal Diffusion And Volumetric Kinetics Of Head And Neck Cancer Magnetic Resonance On A 15 T Mr-Linear Accelerator Hybrid System: A Prospective R-Ideal Stage 2a Imaging Biomarker Characterization/Pre-Qualification Study, Joint Head And Neck Radiation Therapy-Mri Development Cooperative, Mr-Linac Consortium Head And Neck Tumor Site Group

Faculty, Staff and Student Publications

Objectives: We aim to characterize the serial quantitative apparent diffusion coefficient (ADC) changes of the target disease volume using diffusion-weighted imaging (DWI) acquired weekly during radiation therapy (RT) on a 1.5 T MR-Linac and correlate these changes with tumor response and oncologic outcomes for head and neck squamous cell carcinoma (HNSCC) patients as part of a programmatic R-IDEAL biomarker characterization effort.

Methods:Thirty patients with HNSCC who received curative-intent RT at MD Anderson Cancer Center, were included. Baseline and weekly MRI were obtained, and various ADC parameters were extracted from the regions of interest (ROIs). Baseline and weekly ADC parameters were …

Dosimetric Significance Of Manual Density Overrides In Oropharyngeal Cancer, Thomas Lo Greco

Masters Projects

Kilovoltage computed tomography plays a crucial role in radiotherapy planning. However, the presence of high-density metallic objects can introduce streaking artifacts in CT scans, resulting in inaccurate dose calculations by the treatment planning software. Previous studies have explored manual density overrides and artifact reduction algorithms individually to enhance dose calculation accuracy, but their combined application on patient plans within a treatment planning system remains unexplored.

This research aims to assess the necessity of manual density overrides when an artifact reduction algorithm is already employed to address dental artifacts in oropharyngeal cancer treatment plans. A total of 20 previously treated volumetric …

Intensity Modulated Bolus Electron Conformal Therapy (Im-Bect): Methods For Quality Assurance Of Prime Intensity Modulators And Evaluation Of Planned Im-Bect Dose Distributions, Andrew S. Mcguffey

LSU Doctoral Dissertations

Purpose: Intensity-modulated bolus electron conformal therapy (IM-BECT) shapes homogeneous dose distributions to superficial, irregularly-shaped target volumes, avoiding nearby critical structures. This dissertation provides research useful for translating IM-BECT to the radiotherapy clinic by: (1) developing and testing a factory quality assurance (QA) method for fabricated Passive Radiotherapy Intensity Modulator for Electrons (PRIME) devices and (2) verifying an IM-BECT planning and delivery process using end-to-end tests.

Methods: The IM-BECT planning and delivery process determines beam parameters and treatment devices (cutout, bolus, PRIME device) using .decimal’s (Sanford, FL) ElectronRT (eRT) planning system; calculates dose using a pencil-beam redefinition algorithm modified for PRIME …

Addressing The Global Expertise Gap In Radiation Oncology: The Radiation Planning Assistant, Laurence Court, Ajay Aggarwal, Hester Burger, Carlos Cardenas, Christine Chung, Raphael Douglas, Monique Du Toit, David Jaffray, Anuja Jhingran, Michael Mejia, Raymond Mumme, Sikudhani Muya, Komeela Naidoo, Jerry Ndumbalo, Kelly Nealon, Tucker Netherton, Callistus Nguyen, Niki Olanrewaju, Jeannette Parkes, Willie Shaw, Christoph Trauernicht, Melody Xu, Jinzhong Yang, Lifei Zhang, Hannah Simonds, Beth M Beadle

Faculty, Staff and Student Publications

PURPOSE: Automation, including the use of artificial intelligence, has been identified as a possible opportunity to help reduce the gap in access and quality for radiotherapy and other aspects of cancer care. The Radiation Planning Assistant (RPA) project was conceived in 2015 (and funded in 2016) to use automated contouring and treatment planning algorithms to support the efforts of oncologists in low- and middle-income countries, allowing them to scale their efforts and treat more patients safely and efficiently (to increase access).

DESIGN: In this review, we discuss the development of the RPA, with a particular focus on clinical acceptability and …

Multiple Primary Lung Cancers: Treatment Outcomes After Stereotactic Body Radiotherapy (Sbrt), Gyujae Choi, George Chen, Weiyuan Mai, Albert Chen, Angela Zhu

Faculty, Staff and Students Publications

PURPOSE/OBJECTIVES: Patients with lung cancer sometimes present with multiple primary lung cancers (MPLCs), either simultaneously (synchronous) or after treatment of an initial lesion (metachronous). Although open surgery remains a treatment mainstay for patients with stage I-II non-small-cell lung cancer (NSCLC), stereotactic body radiation therapy (SBRT) is an acceptable alternative for patients who are medically unfit for or who refuse surgery. In this study, we retrospectively examine the outcome among patients with early-stage MPLCs treated at our institution with SBRT.

MATERIALS/METHODS: Patients at our institution receiving SBRT for MPLC between June 2011 and March 2020 were reviewed retrospectively. Prior to undergoing …

Differences In Clinical Outcomes Based On Molecular Markers In Glioblastoma Patients Treated With Concurrent Tumor-Treating Fields And Chemoradiation: Exploratory Analysis Of The Spare Trial, Louis Cappelli, Mehak Majid Khan, Allison Kayne, Spencer Poiset, Ryan Miller, Ayesha Ali, Muneeb Khan Niazi, Wenyin Shi, Iyad Alnahhas

Department of Radiation Oncology Faculty Papers

Background: Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. Despite enormous research efforts, GBM remains a deadly disease. The standard-of-care treatment for patients with newly diagnosed with GBM as per the National Cancer Comprehensive Cancer Network (NCCN) is maximal safe surgical resection followed by concurrent chemoradiation and maintenance temozolomide (TMZ) with adjuvant tumor treating fields (TTF). TTF is a non-pharmacological intervention that delivers low-intensity, intermediate frequency alternating electric fields that arrests cell proliferation by disrupting the mitotic spindle. TTF have been shown in a large clinical trial to improve patient outcomes when added to radiation and …

Long-Term Outcomes Of Bevacizumab And Chemoradiation For Locoregionally Advanced Nasopharyngeal Carcinoma: A Nonrandomized Controlled Trial, Nancy Y. Lee, Jonathan Harris, John Kim, Adam Garden, James Mechalakos, David G. Pfister, Anthony T.C. Chan, Kenneth Hu, A. Dimitrios Colevas, Steven Frank, George Shenouda, Voichita Bar-Ad, John N. Waldron, Paul M. Harari, Adam Raben, Pedro Torres-Saavedra, Quynh-Thu Le

Department of Radiation Oncology Faculty Papers

IMPORTANCE: The long-term outcomes associated with adding bevacizumab, a vascular endothelial growth factor inhibitor, to standard chemoradiation have continued to be favorable for a group of patients with locoregionally advanced nasopharyngeal carcinoma (NPC).

OBJECTIVE: To assess long-term toxic effects and clinical outcomes associated with chemotherapy, radiation therapy (RT), and bevacizumab for NPC.

DESIGN, SETTING, AND PARTICIPANTS: This single-arm phase II nonrandomized controlled trial was conducted by the National Cancer Trials Network group and NRG Oncology (formerly Radiation Therapy Oncology Group), with accrual from December 13, 2006, to February 5, 2009, and data analysis from June 26 to July 1, 2019. …

Physician Perceptions On Cancer Screening For Lgbtq+ Patients, Nicolas Nelson, Joseph F. Lombardo, Ayako Shimada, Marissa L. Ruggiero, Alexandria P. Smith, Kevin Ko, Amy E. Leader, Edith P. Mitchell, Nicole L. Simone

Department of Radiation Oncology Faculty Papers

The LGBTQ+ community experiences cancer disparities due to increased risk factors and lower screening rates, attributable to health literacy gaps and systemic barriers. We sought to understand the experiences, perceptions, and knowledge base of healthcare providers regarding cancer screening for LGBTQ+ patients. A 20-item IRB-approved survey was distributed to physicians through professional organizations. The survey assessed experiences and education regarding the LGBTQ+ community and perceptions of patient concerns with different cancer screenings on a 5-point Likert scale. Complete responses were collected from 355 providers. Only 100 (28%) reported past LGBTQ+-related training and were more likely to be female (p = …

Effect Of Sarcopenia On Survival And Spinal Cord Deficit Outcomes After Thoracoabdominal Aortic Aneurysm Repair In Patients 60 Years Of Age And Older, Subhasis Chatterjee, Ann Shi, Luke Yoon, Susan Y Green, Qianzi Zhang, Hiruni S Amarasekara, Vicente Orozco-Sevilla, Ourania Preventza, Scott A Lemaire, Joseph S Coselli

Faculty, Staff and Students Publications

Objective: Sarcopenia (core muscle loss) has been used as a surrogate marker of frailty. We investigated whether sarcopenia would adversely affect survival after thoracoabdominal aortic aneurysm repair.

Methods: We retrospectively reviewed prospectively collected data from patients aged 60 years or older who underwent thoracoabdominal aortic aneurysm repairs from 2006 to 2016. Imaging was reviewed by 2 radiologists blinded to clinical outcomes. The total psoas index was derived from total psoas muscle cross-sectional area (cm2) at the mid-L4 level, normalized for height (m2). Patients were divided by sex-specific total psoas index values into sarcopenia (lower third) and nonsarcopenia (upper two-thirds) groups. …

A Case Report Of Unusual Presentation Of A Rare Renal Tumor, Farzaneh Sharifiaghdas, Behzad Narouie, Mohammad Ghasemi-Rad, Fatemeh Moosavian, Mohadese Ahmadzade, Hamidreza Rouientan

Faculty, Staff and Students Publications

There are very few cases of primary renal Ewing sarcomas, which are characterized by a high rate of metastasis. These tumors are often mistaken for other more common kidney tumors due to their rarity and lack of pathognomonic symptoms in the early stages. A 28-year-old male patient presented to our clinic with a 2-month history of nonproductive progressive cough and left flank pain. The chest was scanned with contrast-enhanced computed tomography, which showed a heterogeneously enhancing mass with central vascularity on the left retroperitoneal. An abdominal dynamic multiphasic magnetic resonance imaging with contrast revealed a large mass that was highly …

Prospective Validation Of Diffusion-Weighted Mri As A Biomarker Of Tumor Response And Oncologic Outcomes In Head And Neck Cancer: Results From An Observational Biomarker Pre-Qualification Study, Abdallah S R Mohamed, Abdelrahman Abusaif, Renjie He, Kareem A Wahid, Vivian Salama, Sara Youssef, Brigid A Mcdonald, Mohamed Naser, Yao Ding, Travis C Salzillo, Moamen A Abobakr, Jihong Wang, Stephen Y Lai, Clifton D Fuller

Faculty, Staff and Student Publications

PURPOSE: To determine DWI parameters associated with tumor response and oncologic outcomes in head and neck (HNC) patients treated with radiotherapy (RT).

METHODS: HNC patients in a prospective study were included. Patients had MRIs pre-, mid-, and post-RT completion. We used T2-weighted sequences for tumor segmentation which were co-registered to respective DWIs for extraction of apparent diffusion coefficient (ADC) measurements. Treatment response was assessed at mid- and post-RT and was defined as: complete response (CR) vs. non-complete response (non-CR). The Mann-Whitney U test was used to compare ADC between CR and non-CR. Recursive partitioning analysis (RPA) was performed to identify …

Investigate The Delivery Efficiency Improvement For Sparc Compared To Impt, Peilin Liu, B A. De Jong, S Chang, Lewei Zhao, G Liu, Craig Stevens, Rohan Deraniyagala, E W. Korevaar, J A. Langendijk, Xiaoqiang Li, Xuanfeng Ding

Conference Presentation Abstracts

Purpose: To assess the efficiency improvement of SPArc compared to IMPT in proton clinical operation.Methods: A random clinical operation day at a proton therapy center with a two room system. Aa total of 10 Head & Neck cancer cases treated on Jan 6th, 2021were selected and SPArc plans were generated for all the cases with similar target coverage and dose constraints of organ at risk (OARs). 3% range uncertainties and 3mm setup uncertainties were applied for robust optimization. The log files of clinical IMPT were exported to calculate true treatment delivery time. The machine-specific delivery sequence model was utilized to …

A Comprehensive Investigation Of Linear Energy Transfer Optimization Effectiveness In Intensity-Modulated Proton Therapy Via Alternating Direction Method Of Multipliers (Impt Let-Admm), Q Fan, G Liu, Lewei Zhao, Xiaoqiang Li, Xuanfeng Ding, S Dai

Conference Presentation Abstracts

Linear energy transfer (LET)-guided optimization in intensity-modulated proton therapy (IMPT) via alternating direction method of multipliers (ADMM) has the potential to improve its biological effectiveness (IMPTLET- ADMM), in which the LET distribution in target can be escalated, while the LET distribution in the organs at risk can be mitigated. This study aims to quantitatively investigate the effectiveness of LET optimization in IMPT via ADMM with different solvers in its iteration loop. Methods: The clinical dose-volume-histogram (DVH) constraint noted dose sub-problem and clinical LET -volume-histogram (LVH) constraint noted LET sub-problem are combined to generate a composite objective function, which is available …

Endovascular Exclusion Of Ascending Aortic Pseudoaneurysm With An Experimental Ascending Aortic Stent-Graft, Chibueze Onyemkpa, Joseph S Coselli

Faculty, Staff and Students Publications

No abstract provided.

The Clinical Usability, Efficiency, And Accuracy Of Combining Deep-Learning-Based Synthetic Ct And Auto-Contouring For Daily Cbct-Based Online Adaptive Radiation Therapy, An Qin, J Xu, N O'Connell, Xuanfeng Ding, Shupeng Chen, D Thill

Conference Presentation Abstracts

Purpose: To evaluate the feasibility of deep-learning and CBCT-based online adaptive radiotherapy(ART) in thorax, Head&Neck, and pelvic regions. Methods: The study utilized ADMIRE(Advanced Medical Image Registration Engine), a research software designed to enable fast online ART through: (1)synthetic CT(sCT) generation from CBCT, (2)automatic segmentation of critical organs(OARs), and(3)deformable image registration(DIR) to transfer the target volume. ADMIRE trained a modified Cycle-Generative-Adversarial-Networks with Structural Similarity Index Map(SSIM) loss term to generate sCT, while the auto-segmentation model was based on a 3D-ResUnet with modification. Site-specific models were trained for three anatomic sites: thorax, pelvic, and head&neck, and for both networks. The study included …

Comparison Of Vmat Beam Complexity With Different Mlc Collimator Rotation And Their Impact On Psqa Pass Rates, David T. To, Michael G. Snyder, Jian Liang

Conference Presentation Abstracts

Purpose: I t has been previously shown that utilizing a collimator angle of ±45° has demonstrated a reduction in MU and VMAT beam complexity. Studies have demonstrated this for VMAT prostate plans with small sample size. In this study we evaluate multiple collimator angles with a larger sample size and different treatment sites. Methods: A total of 17273 VMAT beams were evaluated with beam collimator rotations of 0°, ±5°, ±10°, ±15°, ±30°, ±45°, and ±90°. QA Gamma pass rates for our institution use a 3%/2mm criteria 10% threshold with 95% limit pass rate utilizing Sun Nuclear ArcCheck (helical diode array). …