Influence of physiologic motion on the appearance of tissue in MR images.

摘要: Studies were performed to determine the possible influence of physiologic motion on parenchymal intensity organs in magnetic resonance (MR) images. It is known that periodic associated with respiration and cardiac function causes characteristic artifacts spin-warp The present study shows bulk can also cause striking changes at velocities equivalent craniocaudal respiratory excursion upper abdomen. magnitude effect depends velocity direction respect three orthogonal axes imager technical details pulse sequence. Large systematic errors calculated tissue relaxation times are due this phenomenon. findings have important implications for clinical imaging because artifactual gray-scale relationships among tissues. Some sequences much less sensitive these effects. These results provide guidance selecting MR techniques reduce detrimental other examinations abdomen thorax.