Localized Intense Uptake in the Skull on 18 F-Flortaucipir PET/CT

Area of Science:

• Nuclear Medicine
• Neuroimaging
• Radiopharmaceuticals

Background:

• 18F-Flortaucipir is a key PET tracer for visualizing tau pathology in neurodegenerative diseases like Alzheimer's.
• Focal uptake of 18F-Flortaucipir in areas of osteopenia is an uncommon observation.
• The underlying mechanism for this specific tracer uptake in bone lesions is not well understood.

Purpose of the Study:

• To investigate the mechanism of intense 18F-Flortaucipir uptake in skull osteopenia.
• To differentiate this uptake from typical tau pathology seen in Alzheimer's disease.
• To provide evidence clarifying the phenomenon of radiotracer accumulation in focal bone lesions.

Main Methods:

• Case report detailing PET/CT imaging findings.
• Utilized 18F-Flortaucipir, 18F-FDG, and 18F-Florbetapir PET/CT.
• Correlated imaging findings with sites of reduced bone mineral density in the skull.

Main Results:

• Observed intense 18F-Flortaucipir uptake in two distinct skull lesions.
• No corresponding uptake was detected with 18F-FDG or 18F-Florbetapir at the same sites.
• Lesions were characterized by reduced bone mineral density (osteopenia).

Conclusions:

• The study presents a novel case highlighting 18F-Flortaucipir's unexpected affinity for osteopenic bone.
• This finding suggests a potential non-tau related mechanism for tracer accumulation in specific bone conditions.
• Further research is warranted to elucidate the precise mechanism of 18F-Flortaucipir uptake in focal osteopenia.