| Popis: |
A Charge-Coupled Device (CCD) based electronic imaging system is proposed to overcome limitations of conventional film/screen mammography systems at no additional risk or discomfort to the patient. This thesis presents the design, implementation and evaluation of a number of prototype systems incorporating the latest advances in x-ray intensifying phosphor screen, fiber optic reducer, and CCD technologies. System design is based on an x-ray intensifying screen optically coupled to a high resolution, cooled, scientific CCD through a fiber optic reducer. The performance of the prototype system is compared to theoretical predictions, to the ideal x-ray detector, and to conventional film/screen detectors. Images of breast phantoms captured by the prototype CCD-based system and by conventional mammography systems are presented. Experimental results indicate that the CCD-based system can provide "film quality" images within seconds of x-ray exposure in needle localization, fine-needle aspiration biopsy, and magnification procedures in mammography. |
