Transplantation of Neural Stem Cell-Derived Neurons for Parkinson's Disease

Inclusion Criteria: 1. Able to give informed consent prior to study 2. Male or Female with Diagnostic Criteria of Parkinson's disease 3. Age 35 to 85 years old 4. Parkinson's disease not due to trauma, infection, brain tumor, cerebrovascular disease 5. Hoehn and Yahr Stage III or IV 6. Parkinson's disease observed in the absence of: * Oculomotor palsy * Cerebellar sign * Orthostatic hypotension (drop greater than 20mmHg in mean pressure) * Pyramidal sign * Amyotrophy 7. Good general health or stable medical condition well controlled, without contraindications to anesthesia Exclusion Criteria: 1. Patients with severe dementia and brain atrophy on MRI 2. Patients with severe hypertension; renal, liver, cardiac or other major organ disease; coagulopathy; cancer; other significant systemic illnesses; hepatitis, HIV 3. Patients older than 85 or younger than 35 4. Patients who withhold informed consent 5. Patients with a history of alcohol or drug abuse 6. Sexually active women of childbearing potential without adequate form of birth control 7. Evidence of abnormal coagulation or anticoagulant therapy 8. Pregnancy or lactation 9. History of seizure disorders or current use of antiepileptic medication 10. Severe cognitive impairment 11. Clinically significant laboratory abnormality