Tomosynthesis imaging requires projection images from different viewing angles. Conventional systems use a moving xray source to acquire the individual projections. Using a stationary distributed x-ray source with a number of sources that equals the number of required projections, this can be achieved without any mechanical motion. Advantages are a potentially faster image acquisition speed, hi...

On-board magnetic resonance (MR) image guidance during radiation therapy offers the potential for more accurate treatment delivery. To utilize the real-time image information, a crucial prerequisite is the ability to successfully segment and track regions of interest (ROI). The purpose of this work is to evaluate the performance of different segmentation algorithms using motion images (4 frames...

There is significant interest in delivering precisely targeted small-volume radiation treatments, in the pre-clinical setting, to study dose-volume relationships with tumor control and normal tissue damage. In this work we investigate the IGRT targeting accuracy of the XRad225Cx system from Precision x-Ray using high resolution 3D dosimetry techniques. Initial results revealed a significant tar...

We present a novel 2D/3D deformable registration method, called Registration Efficiency and Accuracy through Learning Metric on Shape (REALMS), that can support real-time Image-Guided Radiation Therapy (IGRT ). The method consists of two stages: planning-time learning and registration. In the planning-time learning, it firstly models the patient’s 3D deformation space from the patient’s time-va...

We present a novel 2D/3D deformable registration method, called Registration Efficiency and Accuracy through Learning Metric on Shape (REALMS), that can support real-time Image-Guided Radiation Therapy (IGRT ). The method consists of two stages: planning-time learning and registration. In the planning-time learning, it firstly models the patient’s 3D deformation space from the patient’s time-va...

TOWARD MAGNETIC RESONANCE ONLY TREATMENT PLANNING: DISTORTIONMITIGATION AND IMAGE-GUIDED RADIATION THERAPY VALIDATIONbyRYAN GLEN PRICEAugust 2016Advisor: Dr. Carri K. Glide-Hurst Major: Medical PhysicsDegree: Doctor of PhilosophyWhile MR-only treatment planning has shown promise, there are still severalwell-known challenges that are currently limiting widespread ...

Introduction: The aim of this retrospective study was to evaluate the variations in delivered dose to the bladder, rectum, and femoral heads of prostate cancer patients during a course of treatment by image-guided radiation therapy (IGRT). Materials and Methods: Overall, 15 patients with prostate cancer were selected and. Each week, for each patient five consecutive cone beam computed tomograph...

Helical tomotherapy (HT) is a novel treatment approach that combines Intensity-Modulate Radiation Therapy (IMRT) delivery with in-built image guidance using megavoltage (MV) CT scanning. The technique utilises a 6 MV linear accelerator mounted on a CT type ring gantry. The beam is collimated to a fan beam, which is intensity modulated using a binary multileaf collimator (MLC). As the patient ad...

Modern radiotherapy is characterised by a better target definition through medical imaging accompanied by significantly improved radiation delivery methods, most notably Intensity-Modulate Radiation Therapy (IMRT). However, the treatment can only be as accurate as the positioning of patients for their daily radiotherapy fraction. It is in this context that a number of imaging modalities - rangi...

Introduction: Electronic Portal Imaging Device (EPID) and Cone Beam Computed Tomography (CBCT) are the preferred tools of Image Guided Radiotherapy (IGRT) and Dose Guided Radiotherapy (DGRT) which have been used for Radiotherapy treatment verifications. As a result, the number of publications dealing with these two tools for radiation treatment verification has increased consi...