There is a serious and growing concern about the CT dose delivered by diagnostic CT examinations or image-guided radiation therapy imaging procedures. To better understand and to accurately quantify radiation dose due to CT imaging, Monte Carlo based CT scanner models are needed. This dissertation describes the development, validation, and application of detailed CT scanner models including a G...

Respiratory monitoring systems are required to supply CT scanners with information on the patient's breathing during the acquisition of a respiration-correlated computer tomography (RCCT), also referred to as 4D CT. The information a respiratory monitoring system has to provide to the CT scanner depends on the specific scanner. The purpose of this study is to compare two different respiratory m...

tools: In addition to these spatial tools we have also created abstract tools such as the color mapper widget and the time control widget. These widgets can be connected to the color mapper and the data sources, and provide direct interactive control of these abstract parameters of the visualization pipeline. Although the design and implementation of the basic concept itself took a substantial ...

CT-scanners are becoming more and more popular imaging modality amongst medical practitioners as their tools for diagnostic practices. Yet, since CT-scanners employ ionizing x-ray beam as the source of imaging light, protection against its damaging effects must be observed closely to ensure that the harmful effects to patients are minimum. Our study involved three Departments of Radiology in th...

BACKGROUND The aim of this study was to assess and compare the effective doses (ICRP 103) in the ankle region of X-ray imaging resulting from a multi slice computed tomography (MSCT) device, two cone beam CT (CBCT) devices and one conventional x-ray device. METHODS Organ dose measurements were performed using 20 metal oxide field effect transistor (MOSFET) dosimeters that were placed in a cus...

PURPOSE The development of flat panel detector technology has resulted in renewed interest in the possibility of generating CT-like images from rotational angiographic acquisitions. At least two commercial products now use cone beam reconstruction software in conjunction with flat panel detectors to produce such images. The purpose of the work presented here is to report on image quality obtain...

Fresh fruits, vegetables and nuts represent a large, highly important, and growing industry. Nonetheless, little is known about their in vivo characterization and morphology, the effect of mechanical harvesting, peelability, postharvest mold, physiological decay, and internal quality. Currently, destructive techniques can be employed to evaluate samples for internal product attributes. However,...