Gas Bubble Motion Artifact in MDCT

OBJECTIVE. The purpose of our study was to characterize the imaging features of an MDCT artifact caused by gas bubble motion.MATERIALS AND METHODS. For the period 2002–2006, the CT images of 10 patients that revealed a curvilinear artifact thought to be due to a gas bubble moving during CT acquisition were retrospectively identified and reviewed by an attending body radiologist. The clinical images were acquired on MDCT scanners. A phantom containing water and moving air bubbles (gas injection rates of 0.1 and 0.5 mL/s) was designed, built, and scanned using a 16-MDCT scanner. Computer simulation was used to test our hypothesis that these observed artifacts originated from moving gas bubbles.RESULTS. Semicircular tubular CT artifacts with attenuation close to that of air were observed in all 10 clinical cases. The acquired MDCT images from the phantom and the computer simulations showed tubular air-attenuation semicircular artifacts that closely matched the imaging findings on the 10 clinical cases. Incre...