Dose and Image Quality Considerations in Computed Tomography

Title of thesis: DOSE AND IMAGE QUALITY CONSIDERATIONS IN COMPUTED TOMOGRAPHY Samir F Abboud, Master of Science, 2011 Thesis directed by: Professor Iacovos Kyprianou Department of Bioengineering The increased use of Computed Tomography as an imaging modality is of concern because of the growing body of evidence linking radiation exposure to cancer incidence. However, a framework does not yet exist for balancing the immediate needs of the clinical task (image quality) with future risks due to the imaging procedure (dose). We developed a method to estimate the shape and thickness of materials yielding attenuation equivalent to that of bow-tie-shaped filters in clinical scanners. The results are especially useful for accurate modeling in Monte Carlo simulations of radiation transport. We then investigated measures of dose and image quality using both simulation and laboratory experimentation. We found that current measures of dose are robust under current clinical conditions. We also found that measures of image quality are object and task specific. Dose and Image Quality Considerations in Computed Tomography by Samir F Abboud University of Maryland, College Park in partial fulfillment of the requirements for the degree of Master of Science 2011 Advisory Committee: Professor Iacovos Kyprianou, Chair/Advisor Professor Yu Chen Professor Yang Tao Thesis sumbitted to the Faculty of the Graduate School of the