. Author manuscript; available in PMC: 2014 Dec 1.
Published in final edited form as: Clin Radiol. 2013 Aug 28;68(12):10.1016/j.crad.2013.07.010. doi: 10.1016/j.crad.2013.07.010
© 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.