Characterization of human renal stones with MDCT: advantage of dual energy and limitations due to respiratory motion.

Objective: Our aim was to determine, using CT attenuation values, the chemical composition of 241 human renal stones placed in a jelly phantom and to analyze the influence of respiratory motion on the classification.

Materials And Methods: The stones were placed in a jelly simulating the X-ray attenuation of the kidneys. A dynamic platform was used to apply to the phantom free-breathing motion (sinusoidal motion in z-axis) and motion due to lack of maintenance of a breath-hold (5 mm x s(-1) in z-axis).