CT artifacts in virtual colonoscopy

摘要

Abstract: A phantom representation of typical colon structures with precisely known geometrical measurements was designed and fabricated. Computed tomography (CT) data were collected using a range of protocols typical for spiral CT colonography. Analysis methods were developed to measure the acquired geometry of the phantom data and characterize distortions/degradation. Simple models were proposed to explain the trends in degradation in the acquisition process versus scanner protocol. Preliminary results indicate that degradation due to CT acquisition will not significantly impact the detection of clinically relevant lesions (dimensions greater than 1 cm). However, the CT acquisition process does place a lower limit on detection size of several millimeters. !9