OBJECTIVES With the increased use of computed tomography (CT) in clinics, dose reduction is the most important feature people seek when considering new CT techniques or applications. We developed an intensity-weighted region-of-interest (IWROI) imaging method in an exact half-fan geometry to reduce the imaging radiation dose to patients in cone-beam CT (CBCT) for image-guided radiation therapy ...

This thesis presents a comparison of high-speed rendering algorithms for the application in 2D/3D-image registration in radiation oncology. Image guided radiation therapy (IGRT) is a technique for improving the treatment of cancer with ionizing radiation by adapting the treatment plan to the current situation using 2D/3D-image registration. To accelerate this procedure, also rendering of Digita...

CHEN-RUI CHOU: REGRESSION LEARNING FOR 2D/3D IMAGE REGISTRATION. (Under the direction of Stephen M. Pizer.) Image registration is a common technique in medical image analysis. The goal of image registration is to discover the underlying geometric transformation of target objects or regions appearing in two images. This dissertation investigates image registration methods for lung Image-Guided R...

PurposeRadiation-induced pulmonary fibrosis (RIPF) is a long-term side effect of thoracic radiation therapy. Hypoxia-induced vascular endothelial mesenchymal transition (EndMT) can occur during the development RIPF. Here, we examined direct contribution HIF-1? (EC-HIF1?) on RIPF.Methods and MaterialsAn inducible Cre-lox-mediated Hif1a deletion mouse line was used to evaluate potential inhibitio...

Imaging dose in radiation therapy has traditionally been ignored due to its low magnitude and frequency in comparison to therapeutic dose used to treat patients. The advent of modern, volumetric, imaging modalities, often as an integral part of linear accelerators, has facilitated the implementation of image-guided radiation therapy (IGRT), which is often accomplished by daily imaging of patien...

Dramatic improvements in radiotherapy equipment have allowed radiation fields to be conformed tumours for more accurate treatment. Successful delivery often requires imaging at every treatment fraction, a method known as image guided therapy (IGRT). But increased X-ray exposes patients doses that carry risks of inducing second cancers normal tissues. Therefore, reductions high-dose margins achi...

IntroductionThis study aimed to evaluate the effect of image-guided radiation therapy (IGRT) on the margin between the clinical target volume (CTV) and planning target volume (PTV) in lung cancer. MethodsThe CTV and PTV margin were determined in three dimensions by four radiation oncologists using a standard method in 10 lung cancer patients, and compared to consensus values. Transfer error was...

Image-guided radiation treatments (IGRT) routinely utilize radio-opaque implantable devices, such as fiducials or brachytherapy spacers, for improved spatial accuracy. The therapeutic efficiency of IGRT can be further enhanced by biological in situ dose painting (BIS-IGRT) of radiosensitizers through localized delivery within the tumor using gold fiducial markers that have been coated with nano...