Benjamin J Shin1, James P Earls2. 1. Department of Radiology, George Washington University School of Medicine, 900 23rd St NW, Suite G-2092, Washington DC, 20037, USA. 2. Department of Radiology, George Washington University School of Medicine, 900 23rd St NW, Suite G-2092, Washington DC, 20037, USA. Electronic address: jearls@mfa.gwu.edu.