Beta-Amyloid PET/CT Scan

Memory and thinking problems can have many possible causes. A beta-amyloid PET/CT scan can help determine whether significant amyloid buildup is present in the brain when the cause of cognitive symptoms is uncertain.

Beta-amyloid is a protein fragment that is normally present in the brain. The brain normally clears beta-amyloid, but in some people it can build up and form clumps called amyloid plaques. These plaques develop in the spaces between brain cells and are one of the key changes associated with Alzheimer’s disease. Amyloid buildup can occur years before noticeable memory or thinking problems develop.

Your physician or neurologist may recommend this scan to:

• Identify the Cause of Cognitive Symptoms: Memory loss can stem from several conditions, including stress, vascular issues, vitamin deficiencies, or neurodegenerative diseases. This scan helps determine whether amyloid plaques are present.  
• Achieve an Early & Accurate Diagnosis: Detecting or ruling out Alzheimer’s disease early gives patients, families, and physicians clarity to make informed decisions sooner.  
• Determine Eligibility for Advanced Treatments: Newer targeted Alzheimer’s immunotherapies work directly to reduce amyloid plaque buildup in the brain and slow cognitive decline. Confirming the presence of amyloid plaques through a PET/CT scan is often a required step to qualify for these emerging treatments.  

A beta-amyloid PET/CT scan is one part of a complete medical evaluation. Your physician will consider the scan results together with your symptoms, medical history, cognitive testing, and other tests when determining the likely cause of your symptoms.

A small amount of a specialized radiotracer is given through an IV in your arm. The tracer travels through your bloodstream to your brain and binds to amyloid plaques.

The PET scanner detects the tracer and creates images showing where amyloid is present.

Your scan will generally be reported as:

• Amyloid-positive scan: Shows a level and pattern of beta-amyloid buildup consistent with moderate to frequent amyloid plaques in the brain. This finding is associated with Alzheimer’s disease but does not, by itself, establish a diagnosis. Amyloid can also be present in some people who do not have dementia. Your physician will interpret the results together with your symptoms, cognitive testing, medical history, and other tests.
• Amyloid-negative scan: Shows little or no significant beta-amyloid buildup in the brain. This makes Alzheimer’s disease less likely to be the cause of current cognitive symptoms.

A Centiloid score is a standardized way of measuring the amount of beta-amyloid detected on an amyloid PET scan. It helps provide a consistent way to report and compare amyloid PET results.

The score may provide additional information when evaluating a patient or comparing scans over time.

A Centiloid score should always be interpreted together with the overall PET scan findings and other clinical information. It does not diagnose Alzheimer’s disease and does not measure the severity of memory or thinking problems.
 

Step 1: Prepare at Home

Fasting is not required for a beta-amyloid PET/CT scan.You may eat normally and take your routine medications unless instructed otherwise by your physician.
Wear comfortable, loose-fitting clothing. Avoid clothing or accessories with metal near your head and neck, such as metal zippers, snaps, hairpins, or jewelry.

Step 2: Radiotracer Administration

Upon arrival, a technologist will place a small needle in a vein in your arm and inject the radiotracer.  

Step 3: Resting Period (45 to 130 Minutes)

You will relax comfortably in a quiet room while the radiotracer travels through your body and reaches the brain. The waiting time varies depending on the specific radiotracer being used.

Step 4: The Scan (10 to 20 Minutes)

You will lie comfortably on a padded table that moves through the PET/CT scanner. The scan is painless. You will simply need to remain still while the images are obtained.

Step 5: After Your Appointment

You may immediately resume normal daily activities, driving, and diet. We recommend drinking extra fluids throughout the remainder of the day to help your body naturally flush out any remaining tracer.  

Yes. The tracer uses a very small, safe dose of radiation that decays naturally and leaves your body within hours. Radiation exposure from a PET/CT scan is well within accepted diagnostic safety limits.  

A beta-amyloid PET/CT scan is an important tool for evaluating Alzheimer’s disease, but the scan alone does not provide a complete diagnosis.
Your physician will consider the PET results along with your symptoms, cognitive testing, medical history, physical examination, and other relevant tests.

A specialized radiologist will evaluate your images and send a detailed report to your referring physician or neurologist, who will meet with you to discuss the findings and next steps.

Contact our Scheduling Department for an appointment:
Phone: 703.698.4441 Option 4
Fax: 703.698.5930
Or click here to make an appointment request

Please have your written physician order and your insurance card in hand when making your appointment.

For safety, children under 12 may not be left in the waiting room without a supervising adult. They may not accompany patients in the exam room. If supervision isn’t available, your appointment will be rescheduled.  Families of Obstetrical patients will be allowed in the room for a limited period of time, but only when an adult accompanies the minor children.