| A new imaging technique called coherent-scatter computed tomography (CSCT) is being developed in the Imaging Research Laboratories at the John P. Robarts Research Institute to measure calcified tissues, such as bone-mineral content distribution (BMCD) for diagnosing osteoporosis. A proof-of-concept CSCT imaging system has been developed previously. However, the image quality and required acquisition time were insufficient. Thus, development of a practical CSCT system was necessary. This thesis describes the first practical CSCT system based on diagnostic x-ray equipment. The following tasks were fulfilled: (1) developing a new real-time (30 frames per second, 640 x 480 pixels per frame and 8-bit per pixel) image acquisition system based on a Silicon Graphics ;During testing of the image acquisition system, noise-power aliasing inherent to the current interline video system was discovered. A theoretical description of the image noise-power spectrum (NPS) for interline and non-interline video formats was conducted using a linear system approach. It was also the first time that the concept of cyclo-stationary random process was applied to medical imaging. (Abstract shortened by UMI.)... |
