1. Department of Radiology, University of California San Diego, San Diego, CA, USA
2. Department of Radiology, VA San Diego Healthcare System, San Diego, CA, USA
3. Department of Radiology, Teikyo University, Tokyo, Japan
4. Canon Medical Systems Corp, Ohtawara, Tochigi, Japan
5. Department of Vascular Surgery, University of California San Diego, San Diego, CA, USA
6. Tobata Kyoritsu Hospital, Kitakyushu, Fukuoka, Japan