[1] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Radiol, Seoul 138736, South Korea
[2] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Endocrinol & Metab, Seoul 138736, South Korea
[3] Univ Ulsan, Coll Med, Asan Med Ctr, Res Inst Radiol, Seoul 138736, South Korea
[4] Daerim St Marys Hosp, Thyroid Ctr, Dept Radiol, Seoul, South Korea
[5] Daerim St Marys Hosp, Thyroid Ctr, Dept Internal Med, Seoul, South Korea
[6] Chung Ang Univ, Coll Med, Dept Radiol, Seoul 156756, South Korea