Chang-Yu Chen1, Yen-Po Wang2, Ching-Liang Lu2. 1. Endoscopy Center for Diagnosis and Treatment, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan. 2. Endoscopy Center for Diagnosis and Treatment, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Brain Science, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan.