Bo Liu1, Francisco J Contreras1, Thomas J Ward2. 1. University of Central Florida College of Medicine, Department of Radiology, Florida Hospital, 601 E. Rollins Street, Orlando, FL 32803. 2. University of Central Florida College of Medicine, Department of Radiology, Florida Hospital, 601 E. Rollins Street, Orlando, FL 32803. Electronic address: thomasjward@gmail.com.