Ty Skyles; Samantha M. Bouchal; Anna Giarratana; Jacob Wengler; Ian Hart; Erin Greig; Harmanjeet Singh; Steve S. Huang; Felipe Martinez; Ba Nguyen; Clifford H. Shin; Ming Yang; Ephraim Parent; W. Hudson Robb; Ana M. Franceschi; Brian Burkett; Derek Johnson; Mary Ellen Koran (2026)..Journal of Nuclear Medicine Technology, 54(1), 10–17.
This review explains how advanced brain imaging techniques are improving the way Alzheimer’s disease (AD) is diagnosed and managed. A key tool isPET imaging (positron emission tomography), which allows doctors to see specific biological changes in the brain while a person is still alive. Different types of PET scans highlight different aspects of the disease.Amyloid PETdetects amyloid-β plaques—abnormal protein buildups that are a hallmark of Alzheimer’s—and is now especially important because some new treatments require confirmation that these plaques are present before therapy can begin.Tau PETimages another protein, tau, which forms tangles inside brain cells and is closely linked to disease severity; this makes it useful for determining how advanced the disease is and for understanding unusual symptoms. Meanwhile,18F-FDG PETmeasures how the brain uses glucose (its main energy source), helping doctors distinguish Alzheimer’s from other types of dementia based on patterns of reduced brain activity.
The review highlights that these imaging methods are becoming more widely available and are increasingly used together with clinical evaluations and other biomarkers (such as those found in blood or cerebrospinal fluid). Improved quantitative techniques—methods that provide precise, repeatable measurements—also allow doctors to track disease progression and monitor how well treatments are working over time. Overall, molecular imaging is shifting Alzheimer’s diagnosis toward a more biology-based approach, enabling earlier and more accurate detection and supporting more personalized treatment strategies.

FIGURE 1.
18F-FDG PET scans of patients without (A) and with (B) AD. (A) Maximum-intensity-projection image showing absence of gross atrophy or pathology. (B) Maximum-intensity-projection image showing characteristic hypometabolism in posterior cingulate, precuneus, and temporoparietal cortices, with relative preservation of metabolism in sensorimotor cortex. This pattern often produces appearance of person wearing headphones, sometimes referred to as “earmuff” or “headphone” sign.