The purpose of this study is to evaluate the impact of imaging the brain as a diagnostic tool in the management of early Parkinson's disease (PD).

The imaging drug used in this study is Ioflupane (123I) Injection, also referred to as DaTscan. DaTscan is FDA approved.

Inclusion Criteria:

• age 18-80;
• diagnosis of idiopathic PD exhibiting at least 2 of 3 cardinal signs (bradykinesia, rigidity and resting tremor);
• maximum duration of previous exposure to anti-parkinsonian therapy being < 8 weeks;
• ability to signed informed consent;
• willingness and ability to complete medication diary and questionnaires;
• if a female subject of child-bearing potential, the use of an effective method of contraception.

Exclusion Criteria:

• current treatment with anti-parkinsonian medication;
• previous treatment with anti-parkinsonian medication for greater than 8 weeks;
• inability to complete questionnaires;
• unwillingness to complete all questionnaires and medication diary;
• subjects with secondary causes of parkinsonism;
• participant has evidence of clinical significant thyroid disease, gastrointestinal, cardiovascular, hepatic, renal, hematologic, neoplastic, endocrine, neurologic, immunodeficiency, pulmonary, or other medical or psychiatric disorder;
• positive serum/urine pregnancy test at any time during the study period;
• the participant has a history of alcohol, narcotic, or any other drug abuse as defined by the DSM-IV within the past 2 years;
• participation in a concurrent PD trial within 60 days.