Radiology, Vol 195, 169-175, Copyright © 1995 by Radiological Society of North America
Simultaneous temporal resolution of cardiac and respiratory motion in MR imaging
JO Fredrickson, H Wegmuller, RJ Herfkens and NJ Pelc
Department of Radiology, Richard M. Lucas Center for Magnetic Resonance Spectroscopy and Imaging, Stanford University, CA 94305-5488.
PURPOSE: To evaluate a magnetic resonance (MR) imaging method that allows
for simultaneous resolution of both the cardiac and respiratory cycles.
MATERIALS AND METHODS: Conventional and phase-contrast cine sequences were
modified to provide additional resolution of the respiratory cycle. Data
were collected in 11 healthy volunteers during MR imaging of the heart and
portal vein. The imaging time was increased over that of a conventional
cine acquisition by a factor equal to the number of frames in the
respiratory cycle. Data were compared with those from comparable sequences
in which only one motion cycle was resolved. RESULTS: In the heart, motion
due to cardiac dynamics was separated from respiration-induced excursions.
The extent of motion could be measured, and artifacts were minimized.
Changes in flow rate as a function of both motion cycles were resolved and
quantified in both the portal vein and superior vena cava. CONCLUSION: This
method allows for simultaneous resolution of cardiac and respiratory motion
cycles and helps provide a more physiologic view of the effects of cardiac
and respiratory variations.
