Radiation Medicine Commons^™

A Retrospective Quantitative Investigation Into Prostate Radiation Treatment Among Patients With Rectal Gas At Simulation, And How It Affects Planning: A South Florida Context., Soufiane Mansouri

Masters Projects

This study examines the effect of Hounsfield Unit (HU) correction of air in rectal tissue on dose distribution during prostate cancer radiation therapy planning. Ten patients treated between 2023 and 2024, of which received 70 Gray (Gy) in 28 fractions, were retrospectively analyzed. Inclusion criteria included the presence of rectal gas during simulation and noncompliance with pre-simulation preparation instructions. Statistical tests, including a standard t-test and a sign test, were used to compare dose planning without HU correction to planning with HU-corrected rectal gas to tissue, focusing on differences in rectal doses and planned target volume doses. Radiation therapy plans …

A Clinical Comparison With The Flattening Free Filter Technique For Lung Stereotactic Body Radiotherapy Using Functional Lung Planning, Addison Gucwa

Masters Projects

Abstract

Introduction

Lung cancer remains the leading cause of cancer incidence and mortality worldwide. Advances in stereotactic body radiation therapy have demonstrated survival rates comparable to surgery, however, they come with a higher risk of developing radiation pneumonitis. The aim of this study was to explore the possibility of minimizing the risk of lung toxicities after stereotactic body radiation therapy to lung tumors with the use of functional lung planning and flattening filter free beams.

Materials and Methods

This retrospective study analyzed treatment planning data from ten patients previously treated with SBRT for inoperable lung tumors. Functional lung volumes were …

A Retrospective Quantitative Comparison Of Auto-Planning Vs. Manual-Planning For Large Breast Patients, Olivia R. Smiley

Masters Projects

Breast cancer is the most prevalent cancer among women in the United States, with many patients undergoing whole breast irradiation (WBI) following lumpectomy. Dosimetrists face challenges in planning WBI for patients with large breasts due to issues related to hotspots, dose uniformity, and extended planning times. Auto-planning tools like EZFluence, which use artificial intelligence, offer potential improvements in planning efficiency and dose distribution. This retrospective quantitative study compares auto-planning using EZFluence with manual planning for 10 large breast patients, aiming to reduce hotspots, achieve a more homogeneous dose, minimize doses to organs at risk (OARs), reduce monitor units (MUs), and …

Comparative Analysis Of Rectum Delineation: Inter-Observer Agreement Among Treatment Planners Versus Auto Segmentation In A Single Institution, Haley Douglas

Masters Projects

Abstract

Introduction

The past 20 years have seen a continuous rise in the cancer patient population, resulting in staffing shortages, longer wait times for patients, and potentially lower-quality care. Artificial intelligence has been incorporated into the healthcare system and has provided ease with understaffing. Using AI technology to delineate structures can reduce planning time and variation between planners. The objective of this research is to assess the level of consistency in the rectum boundary delineation performed by different dosimetrists working at a single institution, as compared to the performance of the AutoContour software. This analysis will help determine the efficacy …

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 …

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 …

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 …

A Quantitative Investigation Of Treating Lung Tumors With Dynamic Conformal Arcs Vs. Vmat For Lung Sbrt Plans, Shawn Loutos

Masters Projects

Introduction

This study aims to investigate the comparisons in dynamic conformal arc, VMAT (no ASC), forced MU limitations (ASC), or a 50/50 hybrid arc (ASC) in how they can improve a lung SBRT case where the tumor is abutting a dose critical structure. The goal of this research is to investigate multiple treatment techniques in an attempt to increase the dose constraint pass rate. The variables in comparison are how well different plan iterations can successfully meet constraints as well as pass a 0.5 modulation complexity score (MCS).

Methods

10 previously treated patients were used in this study who exhibited …

Deep Inspiration And End Exhale Breathhold Evaluation For The Treatment Of Locally Advanced Pancreatic Adenocarcinoma Using The Viewray Mridian Linactm, Tatum Mcglynn

Masters Projects

Introduction

Radiation therapy has been limited in the treatment of locally advanced pancreatic cancer. This is due to the dose tolerance to nearby organs at risk and breathing motion. Advancements in radiation treatment technology have now allowed pancreatic patients to be treated to higher doses in fewer fractions using stereotactic body radiotherapy treatment. With the use of MRI-guided treatments, using the ViewRay MRIdian linac, doses can be escalated using online adaptive treatment planning and real time tracking. However, there has yet to be an optimal breathhold technique investigated that can aid in this process.

Methods

Five patients that had been …

Effects Of Ezfluence Planning Software On Dosimetric Parameter Compliance For Early-Stage Breast Cancer, Jackie Loomis

Masters Projects

Each year over 2 million women are given a breast cancer diagnosis and over half a million women succumb to the disease yearly. As technology advances in the world of radiation oncology, automated planning softwares, such as Radformation’s EZFluence, are being utilized to streamline the treatment planning process. This study was designed to investigate whether the automated plans are dosimetrically equivalent to traditionally planned 3D field in field tangential plans. Is there a disadvantage to using these automated softwares? Three different dosimetrists with varying backgrounds replanned 27 previously treated breast cancer patients and an assortment of comparisons were ran between …

Dosimetric Comparison Of Static Imrt And Vmat Apbi Treatment Planning In The Prone Position For Breast Conservation Therapy, Kelly A. Foucher

Masters Projects

Introduction

Prevalence of early-stage breast cancer is increasing with the aid of preventative screenings and early diagnosis. The standard of care is transforming from conventional approaches with long treatment regimens towards hypofractionation and tissue sparing techniques. Based on studies over the past ten years, there are reasons to consider a partial-breast, hypo fractionated treatment option in the supine position. In practice, aPBI is often produced using several static intensity modulated beams to control dose to the normal breast tissue and limit dose to the heart and lungs. Patients may also be treated in the prone treatment setup in order to …

A Quantitative Investigation At Dose To Tissue When Using Physical Constraints Versus Biological Based Constraints In Pancreatic Carcinoma Patients, Kelly R. Alley

Masters Projects

Introduction

The purpose of this study was to compare dose to organs at risk as well as PTV coverage. Physical objectives, biological objectives, and a combination of the two were utilized to compare which technique provided the best coverage of the PTV while also preserving the greatest amount of healthy tissue.

Methods

Each randomly selected patient had three separate plans created for them. The first plan used only physical based constraints in the form of upper objectives. The second plan used only biological based constraints in the form of gEUD objectives. The third plan used a combination of both upper …

Dosimetric Evaluation Of Fixed Jaw And Jaw Tracking Vmat Treatment Plans For Prostate Cancer With Involved Pelvic Nodes, William Rios

Masters Projects

Intro

A mechanical limitation of modern linacs affecting the quality of radiotherapy treatments of large tumor volumes is the travel length of multicollimator leaves. Considering this limitation, research was carried out to evaluate the dosimetric differences between a split-field fixed-jaw volumetric arc radiotherapy (SF-FJ VMAT) technique and a jaw tracking VMAT (JT VMAT) technique for the treatment of prostate cancer with involved lymph nodes.

Methods

Plans for 16 patients treated with the same dose regimen were created using both techniques. Initial JT-VMAT plans were planned with two arcs to encompass the entire tumor volume without jaw restrictions and jaw tracking …

Analysis Of Racial/Ethnic Disparities And Language Barriers In Radiation Therapy, Carrie Warner

Honors Projects

It is important for every patient within healthcare to have access to and receive quality care no matter their race, ethnicity, and/or primary language. Focusing on cancer care in the United States, there are racial and ethnic disparities as well as language barriers, both within the English language itself and with foreign languages, that prevent patients from receiving high quality care. This meta-analysis provides evidence of current disparities within healthcare that can be applied to the radiation oncology department and reveals suggestions for advancements including the use of language-concordant physicians and medical interpreters. Some of the policies, plans, and resources …