Motion suppression improves quantification of rat liver volume in vivo by magnetic resonance imaging

In response to the presence of certain compounds, rat liver weight can increase. Under the assumption that the liver density does not change, the liver volume will increase as well. To develop the capability to monitor this process noninvasively over time, we used liver volumes determined from MR images to estimate the in vivo liver volumes and weights of normal rats. We acquired multislice, spin-echo images from 18 rats using several protocols for suppression of motion artifacts. We found that volumes determined from data obtained using a combination of gradient moment nulling and respiratory gating, or a combination of signal averaging and "retarded" (after the pi pulse) phase-encoding, produced the most accurate estimates of in vivo liver volume and weight.