[1] Osaka Univ, Dept Future Diagnost Radiol, Grad Sch Med, Suita, Osaka, Japan
[2] Kindai Univ, Dept Radiol, Fac Med, Higashihiroshima, Japan
[3] Osaka Univ, Ctr Twin Res, Grad Sch Med, Suita, Osaka, Japan
[4] Kindai Univ, Dept Neurosurg, Fac Med, Higashihiroshima, Japan
[5] Osaka Univ, Dept Radiol, Grad Sch Med, Suita, Japan
[6] Osaka Univ, Dept Neurosurg, Grad Sch Med, Suita, Osaka, Japan