. Author manuscript; available in PMC: 2011 Feb 1.
Published in final edited form as: Ultrasound Med Biol. 2010 Jan 4;36(2):350. doi: 10.1016/j.ultrasmedbio.2009.10.005
© 2009 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.