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Related Experiment Video

Updated: Feb 5, 2026

Visualization and Quantification of Brown and Beige Adipose Tissues in Mice using [18F]FDG Micro-PET/MR Imaging

Visualization and Quantification of Brown and Beige Adipose Tissues in Mice using [18F]FDG Micro-PET/MR Imaging

Published on: July 1, 2021

Failure of 18F-florbetapir Amyloid PET Imaging after Injection With an Automated Injector Using an Air-vent Filter

Yohji Matsusaka¹, Kaima Suzuki², Akira Seto¹

¹Department of Nuclear Medicine, Saitama Medical University International Medical Center, Saitama, Japan.

Clinical Nuclear Medicine

|February 3, 2026

Summary

A mixed cellulose ester filter trapped 18F-florbetapir radioactivity, preventing Alzheimer disease imaging. Using alternative filters enabled successful PET scans, highlighting filter compatibility for accurate amyloid PET imaging.

Keywords:

automated injector failure filter adsorption positron emission tomography

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Semi-quantitative Assessment Using [18F]FDG Tracer in Patients with Severe Brain Injury

Semi-quantitative Assessment Using [18F]FDG Tracer in Patients with Severe Brain Injury

Published on: November 9, 2018

Area of Science:

Radiochemistry
Nuclear Medicine
Alzheimer Disease Diagnostics

Background:

18F-florbetapir positron emission tomography (PET) is crucial for diagnosing Alzheimer disease.
Accurate amyloid PET imaging is essential for assessing eligibility for disease-modifying therapies.
Filter compatibility in automated injectors is critical for radiotracer delivery.

Purpose of the Study:

To investigate the cause of failed 18F-florbetapir PET imaging in a patient with cognitive impairment.
To identify the specific component responsible for radiotracer retention during injection.
To provide recommendations for optimal radiotracer administration protocols.

Main Methods:

Patient presented for 18F-florbetapir PET imaging for Alzheimer disease assessment.
Initial PET scan showed minimal brain uptake; radioactivity was retained in an automated injector's air-vent filter.
Subsequent injections using alternative filters (non-mixed cellulose ester) resulted in successful PET imaging.

Main Results:

The air-vent filter, composed of mixed cellulose ester, trapped nearly all 18F-florbetapir radioactivity.
This retention led to inadequate radiotracer delivery to the brain, causing diagnostic failure.
Alternative filters demonstrated no significant radiotracer retention, allowing for successful imaging.

Conclusions:

Mixed cellulose ester filters are incompatible with 18F-florbetapir and should not be used for injection.
Filter selection is critical to ensure accurate radiotracer delivery for amyloid PET imaging.
This finding impacts Alzheimer disease diagnostic procedures and clinical trial eligibility assessments.