1. Department of Neurology, Dongguk University Ilsan Hospital, Goyang, Korea.
2. Department of Neurology, Seoul National University College of Medicine, Seoul, Korea.
3. Department of Neurology, Inje University Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Korea.
4. Department of Hepatology, Dongguk University Ilsan Hospital, Goyang, Korea.