Amyloid and Tau PET: — What These Scans Show and Who Can Get One

Amyloid PET requires a specialised F-18 tracer with a short shelf life, produced at a nearby cyclotron facility — which is why it is available only at a small number of centres. At the time of writing, availability in Hyderabad is very limited and is not part of routine clinical practice. A CION centre coordinator can find out what is currently accessible through partner imaging centres and help arrange referral if your neurologist has recommended the scan.

No. Amyloid deposits are found in some people with completely normal memory, and the result has to be read alongside your clinical history, cognitive tests, and MRI. A positive result increases the probability that Alzheimer's pathology is present — it does not confirm the disease on its own. A negative result is more definitive: it essentially rules out amyloid pathology and makes Alzheimer's very unlikely. Both results need a neurologist to interpret them in your specific context.

You can ask about it, but booking it without a referral is not clinically appropriate and most centres require one. The scan is only useful when a specialist will interpret the result alongside your full clinical picture — a result without that context gives you a number, not an answer. If you think it may apply to you, ask your neurologist whether it has been considered and why or why not. That conversation is more useful than a scan booked independently.

Some amyloid-targeting treatments approved outside India require a positive amyloid PET as part of the eligibility process. Whether those treatments are accessible in India, whether you would be eligible, and what the current regulatory position is are questions your neurologist needs to answer — the situation is changing. If accessing newer treatments is your reason for asking about the scan, say so directly to your neurologist. It changes the decisions being made.

A standard PET-CT in oncology uses FDG — a glucose tracer that shows metabolic activity across the body. Amyloid PET uses a completely different tracer that binds specifically to amyloid plaques in brain tissue. A brain MRI shows structure — it identifies atrophy and rules out other causes of memory loss, but cannot detect protein deposits. Each test answers a different question, and amyloid PET is not a replacement for MRI. Your neurologist will say which tests apply to your situation.

If the scan is genuinely indicated, your neurologist may refer you to a specialist centre in another city, or arrange it through a partner facility. In many cases a clinical decision can be made without it — CSF analysis, newer blood-based biomarker tests, or the overall clinical picture may be sufficient. Ask your neurologist whether amyloid PET is essential for your particular decision, or whether another test would answer the same question. Sometimes ruling out alternatives is more achievable than arranging a rare scan.