Introduction: This study examined the dosimetric effects based on the rotational setup error to correct patient setup errors occur during volumetric modulated arc radiotherapy (VMAT) for brain tumor patients. Material and Methods: This study included 1129 cases of cone beam computed tomography (CBCT) images obtained from 46 brain tumor patients, who experienced VMAT and used the 6DoF (degree o...

Introduction Patient set-up optimization is required in radiotherapy to fill the accuracy gap between personalized treatment planning and uncertainties in the irradiation set-up. In this study, we aimed to develop a new method based on neural network to estimate patient geometrical setup using 4-dimensional (4D) XCAT anthropomorphic phantom. Materials and Methods To access 4D modeling of motion...

introduction patient set-up optimization is required in radiotherapy to fill the accuracy gap between personalized treatment planning and uncertainties in the irradiation set-up. in this study, we aimed to develop a new method based on neural network to estimate patient geometrical setup using 4-dimensional (4d) xcat anthropomorphic phantom. materials and methods to access 4d modeling of motion...

Background: In intensity modulated radiation therapy, cone beam computed tomography (CT) has been used to evaluate patients prior to treatment. This study conducted a comparative evaluation of the image reconstruction ability of the clinically used half-fan bowtie filter and the full-fan bowtie filter. Materals and Methods: A CT simulation marker was inserted inside a human phantom, and the pel...

PURPOSE This study investigated setup error and effectiveness of weekly image-guided radiotherapy (IGRT) of TomoDirect for early breast cancer. MATERIALS AND METHODS One hundred and fifty-one breasts of 147 consecutive patients who underwent breast conserving surgery followed by whole breast irradiation using TomoDirect in 2012 and 2013 were evaluated. All patients received weekly IGRT. The w...

This paper introduces a new notion related to the traveling salesperson problem (TSP) — the notion of the TSP ratio. The TSP ratio of a TSP instance I is the sum of the marginal values of the nodes of I divided by the length of the optimal TSP tour on I, where the marginal value of a node i ∈ I is the difference between the length of the optimal tour on I and the length of the optimal tour on I...

Larynx may alternatively serve as a target or organs at risk (OAR) in head and neck cancer (HNC) image-guided radiotherapy (IGRT). The objective of this study was to estimate IGRT parameters required for larynx positional error independent of isocentric alignment and suggest population-based compensatory margins. Ten HNC patients receiving radiotherapy (RT) with daily CT on-rails imaging were a...