Measuring patient motion in HR-pQCT

Patient motion affects image quality in high-resolution peripheral quantitative computed-tomography (HR-pQCT) and the quantitative analysis of bone quality using morphological parameters. We propose a method to automatically quantify the amount of patient motion contained in an acquired sinogram based on the Helgason-Ludwig consistency conditions (HLCC). The relation between the motion measure and the observed percent error in morphological parameters is studied, in datasets with computer simulated in-plane patient motion. Results indicate that the proposed motion measure is independent of bone type, and relates to the magnitude of percent errors in morphological parameters, as well as the presence of visible motion artifacts.