1. Department of Neurosurgery, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan
2. Neuroscience Research Center, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan
3. School of Medicine, Chang Gung University, Taoyuan 333, Taiwan
4. Molecular Medicine Research Center, Chang Gung University, Taoyuan 333, Taiwan
5. Department of Ophthalmology, China Medical University Hospital, Taichung 402, Taiwan
6. Department of Neurosurgery, Chang Gung Memorial Hospital at Keelung, Keelung 204, Taiwan