Pediatric FDG PET/CT: Physiologic Uptake, Normal Variants, and Benign Conditions

Published Online:Sep 1 2009https://doi.org/10.1148/rg.295085247

Abstract

Normal distribution of FDG uptake, physiologic variants in distribution, benign lesions that may be misinterpreted as malignancies, and PET/CT artifacts are discussed and illustrated with respect to pediatric oncology patients.

Positron emission tomography (PET) with 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) is increasingly being used in the evaluation of pediatric oncology patients. However, the normal distribution of ¹⁸F FDG uptake in children is unique and may differ from that in adults. A number of physiologic variants are commonly encountered, including normal physiologic uptake in the head and neck, heart, breast, thymus, liver, spleen, gastrointestinal tract, genital system, urinary collecting system, bone marrow, muscles, and brown adipose tissue. Benign lesions with increased ¹⁸F FDG uptake are also frequently seen and can be misinterpreted as malignancies. In addition, the use of combined PET/computed tomographic (CT) scanners is associated with pitfalls and artifacts such as attenuation correction and misregistration. Proper interpretation of pediatric ¹⁸F FDG PET/CT studies requires knowledge of the normal distribution of ¹⁸F FDG uptake in children, as well as of the aforementioned physiologic variants, benign lesions, and PET/CT-related artifacts. Knowing these potential causes of misinterpretation can increase accuracy in PET image interpretation, decrease the number of unnecessary follow-up studies or procedures, and improve patient treatment.

References

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Article History

Received: Dec 22 2008
Revision received: Feb 25 2009
Revision received: Mar 30 2009
Accepted: Apr 7 2009
Published in print: Sept 2009

Vol. 29, No. 5

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