Medicine and Health Sciences Commons^™

Interfraction Variability Of Breathing Amplitude Of Patients Undergoing Sbrt Lung Treatment And The Potential Impact On Dosimetry, Christian Padilla Gallegos

Culminating Experience Projects

Abstract

Introduction

The study investigated the consistency of free breathing planning margins for fractionated SBRT treatment in the lung. The study compared breathing motion from the average CT (AVE CT) scan to the Cone Beam Computed Tomography (CBCT) from each treatment session. Various breathing techniques were also discussed, including deep inspiration breath hold (DIBH), gated breathing, abdominal compression (AC), and free breathing (FB). Free-breathing may lead to overdosing on surrounding healthy tissue if significant changes in breathing amplitude occur. Abdominal compression or breath hold may reduce abnormal breathing movement if erratic breathing occurs. The study's aim was to ensure the …

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

Culminating Experience 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 …

Plan Quality Comparison Between Cyberknife And Vmat Lung Sbrt After Modified Cyberknife Treatment Times., Lindsey Money

Culminating Experience Projects

Introduction

This retrospective study will aim compare Cyberknife SBRT and VMAT SBRT lung plans quality when the Cyberknife plans are replanned to have a comparable treatment time to the VMAT plans. Having data to show the difference in plan quality between the two treatment techniques could be a useful tool when deciding the best treatment option.

Methodology

Select ten SBRT lung patients who were all treated using the Cyberknife and plan a comparable VMAT treatment for each. Modify the original Cyberknife treatment plan so that the treatment time is similar to that of the corresponding VMAT plan. Then, evaluate and …

Spine Stereotactic Body Radiation Therapy (Sbrt): Using Biological Objectives In Treatment Planning A Comparative Plan Study, Joseph E. Pagano

Culminating Experience Projects

Introduction: The purpose of the study is intended to determine if gEUD optimization can be useful in the treatment planning for SBRT to the spine. The main goal was to study the dose effects when placing gEUD objectives on the targeted vertebral structure (Target gEUD) and spinal cord (Upper gEUD). Furthermore, to provide a better understanding of the utility of this tool.

Methods: Two planning techniques for SBRT spine treatments were compared retrospectively on 10 radiation therapy patients. The Varian Eclipse treatment planning system was utilized with the volumetric modulated arc therapy treatment technique. The planning techniques used different objectives …

A Quantitative Comparison Of Linac Vs. Cyberknife For Sbrt Prostate Boost: A Retrospective Study, Vicente Miguel Ornelas

Culminating Experience Projects

Purpose: The purpose of this study is to retrospectively evaluate the quantitative difference of prostate SBRT boost between LINAC boost and CK boost treatments, with a primary plan using LINAC volumetric modulated arc therapy.

Materials and Methods: Nine prostate cancer patients were treated with a SBRT fractionated schedule of 21 Gy in 3 fractions, given every other day over the course of a week. The LINAC-BOOST were created by the researcher followed the same fractionation schedule, treatment volumes, OAR, and dose constraints as the original CK-BOOST treatment. The CK-BOOST was completed on the Multiplan (v14) TPS, while the LINAC-BOOST was …

In-Phantom Film Measurements Of Two Treatment Planning Systems For Single-Fraction Spine Sbrt, Michael J. Taylor

LSU Master's Theses

Purpose: Treatment planning accuracy for spine stereotactic body radiation therapy (SBRT) varies depending on the dose calculation algorithm utilized in the treatment planning system (TPS). This project compared the end-to-end accuracy between spine SBRT plans calculated in a convolution-superposition based TPS (TPS_CS) and Monte Carlo based TPS (TPS_MC) with radiochromic film measurements. The hypothesis was that TPS_MC would calculate the dose gradient in the critical region between the vertebral body and the spinal cord more accurately than TPS_CS.

Methods: Single-fraction spine SBRT treatments following RTOG 0631 and local institutional guidelines were planned in …

A Dosimetric Study On Photon Beam Energies With And Without A Flattening Filter In Sbrt Treatments For Prostate Cancer, Alexis F. Puruleski

Culminating Experience Projects

Purpose: The role of radiation therapy in managing prostate cancer has developed and improved greatly throughout the years. The purpose of this study was to analyze a newly developing method of treatment practices with two different therapy energies.

Methods: This retrospective study pulled patient data from the facility’s treatment planning system database who had primary prostate cancer treated to the prostate bed. Each patient was planned for the same treatment technique with two different beam energies, 6X and 6FFF (flattening filter free).

Results: A two-sample t-test was done to compare means of the max doses to the bladder, rectum, and …

Evaluation Of The Effectiveness Of Anisotropic Analytical Algorithm In Flattened And Flattening-Filter-Free Beams For High Energy Lung Dose Delivery Using The Radiological Physics Center Lung Phantom, Roman Repchak, David Scott Followill

Dissertations & Theses (Open Access)

The effectiveness of the Anisotropic Analytical Algorithm (AAA) implemented in the Eclipse treatment planning system (TPS) was evaluated using theRadiologicalPhysicsCenteranthropomorphic lung phantom using both flattened and flattening-filter-free high energy beams. Radiation treatment plans were developed following the Radiation Therapy Oncology Group and theRadiologicalPhysicsCenterguidelines for lung treatment using Stereotactic Radiation Body Therapy. The tumor was covered such that at least 95% of Planning Target Volume (PTV) received 100% of the prescribed dose while ensuring that normal tissue constraints were followed as well. Calculated doses were exported from the Eclipse TPS and compared with the experimental data as measured using thermoluminescence detectors …