Detecting rapid organ motion using a hybrid MR-ultrasound setup and Bayesian data processing

Purpose: In the context of image-guided therapy, MR images with good spatial and temporal resolution, good spatial coverage, good SNR and excellent contrast characteristics are often desired and rarely attained. To reap the benefits of the superior contrast capabilities of MRI one may need to sacrifice somewhat the temporal resolution. A hybrid MRultrasound setup was developed so that the very high acquisition rates achieved by the ultrasound (US) system might help compensate for a slower and presumably higher-quality MR acquisition (Fig. 1). The setup and algorithm utilized here can track organ motion during regular breathing and also detect/handle the more drastic motion involved in coughing or gasping.