. Author manuscript; available in PMC: 2013 Sep 1.
Published in final edited form as: Ultrasound Med Biol. 2012 Jul 3;38(9):1568–1575. doi: 10.1016/j.ultrasmedbio.2012.04.023
© 2012 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.