Ability Of ([18F]-AV-45) PET Scan to Distinguish Alzheimer's Disease Subjects From Cognitively Normal Individuals

Evaluation of the Ability of a Novel [18F] Amyloid Ligand ([18F]-AV-45) to Distinguish Patients With a Clinical Diagnosis of Alzheimer's Disease From Cognitively Normal Elderly Individuals

This study will evaluate the performance characteristics of a novel [18F] amyloid detection ligand (18F]-AV-45) with respect to its ability to distinguish patients with clinically-diagnosed probable Alzheimer's disease from cognitively normal elderly subjects and to independently compare its diagnostic performance characteristics with the ability of [11C]PIB to correctly categorize the same subjects.

SPECIFIC HYPOTHESES

1. Individuals with a clinical diagnosis of probable Alzheimer's disease will have increased brain retention of [18F]-AV-45 compared to cognitively normal elderly individuals.
2. There will be no clinically meaningful difference in the amyloid retention performance characteristics of [18F]-AV-45 and [l1C]PIB.

15 patients with a clinical diagnosis of probable Alzheimer's disease and 15 cognitively normal elderly control subjects will receive both [18F]-AV-45 and [11C]PIB to compare the diagnostic performance characteristics of each amyloid ligand to distinguish AD from normal subjects. In addition to clinical diagnostic category, ligand retention will be evaluated with respect to measures of symptom severity and cerebrospinal fluid levels of amyloid and tau.

Inclusion Criteria:

• Normal subjects: mini-mental state examination (MMSE) 27-30, clinical dementia rating (CDR) = 0, no symptoms of depression
• Alzheimer's subjects: MMSE 18-26, CDR >=0.5, University of Pennsylvania Alzheimer's Disease Center consensus diagnosis of probable AD, absence of abnormalities on MRI

Exclusion Criteria:

• other neurological disease
• evidence of MRI abnormality
• psychiatric disorder
• alcohol abuse
• clinically significant lab abnormalities
• residence in nursing facility
• participation in clinical trial with experimental medication in past 1 month