[1] Tohoku Univ, Dept Radiol Technol, Grad Sch Med, Aoba Ku, 2-1 Seiryo, Sendai, Miyagi 9808575, Japan
[2] Sendai Kousei Hosp, Dept Radiol, Aoba Ku, Hirosemachi 4-15, Sendai, Miyagi 9800873, Japan
[3] Tohoku Univ, Int Res Inst Disaster Sci, Div Disaster Med, 6-6-4 Aoba, Sendai, Miyagi 9808579, Japan
[4] Sendai Kousei Hosp, Dept Resp Med, Aoba Ku, Hirosemachi 4-15, Sendai, Miyagi 9800873, Japan
[5] Sendai Kousei Hosp, Dept Cardiovasc Med, Aoba Ku, Hirosemachi 4-15, Sendai, Miyagi 9800873, Japan