1. Department of Diagnostic and Interventional Imaging, McGovern Medical School at the University of Texas Health Science Center at Houston, Houston, TX.
2. Department of Diagnostic Radiology, Mayo Clinic, Scottsdale, AZ.
3. Department of Radiology, University of Florida College of Medicine, Jacksonville, FL.
4. Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI.
5. Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, 1400 Pressler St, Houston, TX 77030.