Ultrasound-guided MRI: preliminary results using a motion phantom.

In principal, both ultrasound (US) imaging and MRI can be performed simultaneously within the magnetic field of the scanner due to their different physical natures (i.e., sound waves vs. electromagnetic radiation). One potential application is to use US information for dynamic spatial organ localization to improve MR imaging, similar to MR navigator echoes. In this work, preliminary results are presented for US-guided MRI using position and orientation information extracted from US data to update the image slice position of an SSFP sequence in real time. Effective prospective motion compensation is shown for a phantom whose sinusoidal displacement can be fully corrected. Possible applications of simultaneous US-MRI acquisitions include real-time US-guided cardiac MRI or interventional procedures. Copyright 2004 Wiley-Liss, Inc.