A quantitative analysis of four dimensional computed tomography

This project assesses the four dimensional computed tomography (4DCT) capabilities of the Philips Brilliance Big Bore CT scanner (Philips Medical Systems, Cleveland, OH). A mechanical phantom imparts clinically relevant motions to acrylic spheres of various diameters. The size, shape, and position of these spheres, as measured with 4DCT, are compared to their true size, shape, and position. An evaluation of image quality is also performed. Maximum discrepancies between physical and imaged volumes, for all sphere sizes and motion ranges, did not exceed 2.6 mm (mean = 1.2 mm, standard deviation = 0.4 mm). For approximately tissue equivalent density objects, mean CT...