1. Department of Cardiovascular Medicine, Nagasaki University Graduate School of Biomedical Sciences , 1-7-1 Sakamoto, Nagasaki 852-8501 , Japan
2. Ultrasound Imaging Center, Nagasaki University Hospital , Nagasaki , Japan
3. Department of Pathology, Nagasaki University Hospital , Nagasaki , Japan
4. Department of Neurology, Graduate School of Medical Sciences, Kumamoto University , Kumamoto , Japan