[1] Seoul Natl Univ, Coll Med, Dept Anesthesiol & Pain Med, Med Virtual Real Res Grp, Seoul, South Korea
[2] Seoul Natl Univ, Bundang Hosp, Dept Anesthesiol & Pain Med, Seongnam, South Korea
[3] Seoul Natl Univ, Childrens Hosp, Dept Pediat Surg, Seoul, South Korea
[4] Seoul Natl Univ, Coll Med, Dept Prevent Med, Seoul, South Korea
[5] Seoul Natl Univ, Coll Med, Dept Surg, Seoul, South Korea