A methodology for co-registering abdominal MR images over multiple breath-holds.

Previous studies have demonstrated that the SNR of abdominal MR images can be increased by averaging images obtained in different breath-hold acquisitions. In this note, the authors present a simple new methodology for ensuring that images acquired in multiple breath-hold periods are accurately co-registered. Within each breath-hold, a quick coronal scout scan is followed by a longer axial scan. The scout is used to position the axial slices in a fixed position relative to the organ under examination. This MR technique can, in principle, be automated so as to add less than 1 s to the imaging time of the axial scan. The method can be used to increase SNR by signal averaging or to co-register images acquired during, for example, uptake of contrast agents. SNR improvement with negligible blurring is demonstrated in liver images acquired by this method from healthy volunteers.