Introduction: The accuracy of the patient setup and tumor location are major factors that determine the efficacy of radiotherapy treatment planning. In the prostate radiotherapy, reproducibility of the prostate location for each treatment fraction is problematic owing to varying filling of the rectum and bladder. According to this, the aim of this study was to measure the inte...

The study aimed to investigate the difference of setup errors on different registration in the treatment of nasopharyngeal carcinoma based on weekly cone-beam computed tomography (CBCT). Thirty nasopharyngeal cancer patients scheduled to undergo intensity-modulated radiotherapy (IMRT) were prospectively enrolled in the study. Each patient had a weekly CBCT before radiation therapy. In the entir...

The aim of the present study was to investigate the role of CTVision in interfractional setup errors during intensity-modulated radiation therapy (IMRT) in 12 nasopharyngeal carcinoma (NPC) patients. The trend of setup errors as a function of time during a fractionated radiotherapy course was investigated, and the influence of reconstructive thickness on image reconstruction for setup errors wa...

The purpose was to determine dose-delivery errors resulting from systematic rotational setup errors for fractionated stereotactic radiotherapy using direct simulation in a treatment planning system. Ten patients with brain tumors who received intensity-modulated radiotherapy had dose distributions re-evaluated to assess the impact of systematic rotational setup errors. The dosimetric effect of ...

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...

BACKGROUND The reproducibility of patient setup for radiotherapy is based on various methods including external markers, X-rays with planar or computerized image acquisition, and, more recently, surface matching imaging. We analyzed the setup reproducibility of 16 patients affected by prostate cancer who underwent conformal radiotherapy with curative intent by using a surface image registration...

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...

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...