The patient will visit a dementia expert (physicians board-certified in neurology, psychiatry, or geriatric medicine) who will determine if the patient meets the AUC and if he or she consents to participate in the study. If so, the dementia expert will refer the patient to a PET facility for an amyloid PET scan and will complete a pre-PET assessment within 30 days of the PET scan.

To guide clinicians on how best to use amyloid PET in the evaluation of people with cognitive decline, an expert group convened by the Alzheimer’s Association and the Society of Nuclear Medicine and Molecular Imaging developed appropriate use criteria (AUC) for amyloid PET scans. According to the AUC, brain amyloid PET imaging should only be considered in people with clear, measurable cognitive deficits when substantial diagnostic uncertainty remains even after a comprehensive evaluation by a dementia specialist, and in whom knowledge of amyloid status is expected to change management.

After the PET scan, the patient will meet with the dementia expert to discuss the results. The patient will return to the dementia expert approximately 90 days after the first visit for a post-PET assessment. The IDEAS Study will also obtain Medicare administrative claims for each participant for the year following the amyloid PET scan.

A patient will be eligible for the IDEAS Study if there is diagnostic uncertainty after a comprehensive clinical evaluation by a dementia expert, including laboratory tests (complete blood count, comprehensive metabolic panel, thyroid function tests and vitamin B12 level) and structural brain imaging (CT or MRI). Information about other diagnostic tests completed prior to referral (e.g., lumbar puncture, FDG-PET) will be collected but these tests are not required.