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 d etermined from MR images to estimate the in vivo liver volumes and wei ghts of normal rats. We acquired multislice, spin-echo images from 18 rats using several protocols for suppression of motion artifacts. We f ound that volumes determined from data obtained using a combination of gradient moment nulling and respiratory gating, or a combination of s ignal averaging and ''retarded'' (after the pi pulse) phase-encoding, produced the most accurate estimates of in vivo liver volume and weigh t.