The Use of Contrast-Detail-Dose Evaluation of Image Quality in a Computed Tomographic Scanner

Abstract

Limiting-perception measurements of hole patterns in computed tomography reconstructions of a low-contrast phantom are used to generate contrast-detail-dose diagrams for various contrasts, hole diameters, dose, and system modulation transfer functions (MTF). These curves are then divided into MTF-dominated, transition, and noise-dominated regions. The low-contrast perceptibility and image noise are parameterized and compared. A limiting-perception factor is defined and is shown to be nearly independent of contrast, hole diameter, dose, and MTF in the noise-dominated region.