Despite new rapid image acquisition techniques high-quality MRI data requires data collection times of several seconds or minutes. Any kind of uncompensated object movement on this time scale will lead to blurring, ghosting or other artifacts in the resulting images. All currently available motion correction schemes employ triggering, gating or some sort of navigator echo, which frequently give rise to large amounts of rejected data, compromised image quality or a significant amount of residual blurring. We are proposing a hybrid approach that employs ultrasound images to monitor the position of the target organ. The spatial information is then passed along to the MRI scanner, which adjusts the slice orientation accordingly. This method effectively allows MR image acquisition in the reference frame of the moving organ and not that of the stationary MRI scanner. Ultrasound-guided MRI should permit dramatic improvements in imaging the heart or abdominal organs that are affected by physiological motion.
Feinberg, David A; Giese, Daniel; Bongers, D Andre et al. (2010) Hybrid ultrasound MRI for improved cardiac imaging and real-time respiration control. Magn Reson Med 63:290-6 |