Masanori Murakami1, Noriyasu Morikage2, Osamu Yamashita2, Kimikazu Hamano2. 1. Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan. Electronic address: muraka3@yamaguchi-u.ac.jp. 2. Division of Vascular Surgery, Department of Surgery and Clinical Science, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan.