The goal of this project is to quantify brain fibrin content using 64Cu-FBP8-PET in the brains of subjects ranging from cognitively normal to clinically diagnosed with ADRD to evaluate potential regional differences.

While there are many potential therapeutics being evaluated for Alzheimer's disease and related dementias (ADRD), there is currently no known cure for ADRD and its origin and pathophysiology are still not well understood. However, the association of fibrin with ADRD is becoming increasingly clearer. Up to now it was not possible to quantify brain fibrin in vivo to better elucidate its role in ADRD, but recently, 64Cu-FBP8 was proposed as a tool to detect thrombus anywhere in the body. This unique tool will allow us to non-invasively assess brain fibrin levels in at-risk and ADRD subjects.

The goal of this project is to use 64Cu-FBP8-PET in the brains of subjects ranging from cognitively normal to clinically diagnosed with ADRD to assess fibrin levels. It is expected that about 30 people will take part in this research study. 64Cu-FBP8-PET is not currently approved by the U.S. Food and Drug Administration (FDA).

Inclusion Criteria:

• Age between 55 and 90 years
• Ability to provide informed consent
• Specific to healthy volunteers: no history of ADRD
• Specific to ADRD subjects: clinical diagnosis of AD - either amnestic or atypical, clinical severity ranging from MCI to moderate dementia (CDR 0.5-2.0), MMSE score greater than or equal to 15 and/or MOCA greater than or equal to 12
• Specific to BAnD subjects: referred through the Brain Aging and Dementia (BAnD) research registry

Exclusion Criteria:

• MR contraindications such as: electrical implants such as cardiac pacemakers or perfusion pumps; ferromagnetic implants such as aneurysm clips, surgical clips, prostheses, artificial hearts, valves with steel parts, metal fragments, shrapnel, tattoos near the eye, or steel implants, ferromagnetic objects such as jewelry or metal clips in clothing
• Preexisting medical conditions including a likelihood of developing seizures or claustrophobic reactions, and any greater than normal potential for cardiac arrest
• Subjects whose estimated glomerular filtration rate (eGFR) < 60 mL/min will be excluded from receiving the gadolinium-based contrast agent
• Research-related radiation exposure exceeding current Massachusetts General Hospital (MGH) Radiology Department guidelines (i.e. 50 millisievert in the prior 12 months)
• 3. In line with published MGH IRB guidelines for pregnancy must be ruled out by urine ß-HCG if answers to screening questions suggest that pregnancy is possible and if female participants are premenopausal and of child-bearing age. Subjects will not be able to enroll if they are breastfeeding.