Low-Dose CT Examinations in Crohn's Disease: Impact on Image Quality, Diagnostic Performance, and Radiation Dose

Abstract

OBJECTIVE. The objective of this study was to evaluate the image quality and diagnostic performance of simulated low-dose MDCT examinations in patients with Crohn's disease.MATERIALS AND METHODS. Thirty-five MDCT examinations from 25 patients (14 males and 11 females; age range, 16–86 years) with known or suspected Crohn's disease were retrospectively evaluated. The MDCT images (5 mm thickness) were modified by artificially introducing noise using volume CT noise simulation software to simulate low-dose MDCT data acquired with noise indexes (NIs) of 18–35. The 175 MDCT image data sets generated were then randomized and reviewed by two readers to assess the subjective image quality and diagnostic accuracy for confidently detecting Crohn's disease findings on a 5-point scale (1, definitely absent; 5, definitely present). The image quality, diagnostic performance, and radiation dose from the original MDCT examinations served as a reference standard for comparison.RESULTS. The simulated low-dose CT images wit...