Abstract
Background
The biodistribution of 18F-FDG has been well described in both adults and children. Many findings are limited to children and warrant understanding prior to interpretation.
Objective
To determine the normal level of conus medullaris uptake, not previously reported in the literature to date, in a series of consecutive FDG PET/CT scans performed in children.
Materials and methods
With IRB approval, we retrospectively reviewed 100 consecutive whole-body pediatric 18F-FDG PET/CT examinations obtained for various clinical indications. Scans that showed visible uptake of FDG at the conus were objectively evaluated, and standardized uptake value (SUV) was determined. Maximum SUV of the conus was compared to background, normal liver and lung, and ratios were recorded. Pathology in the conus was excluded.
Results
The scans of 100 patients ages 5 months to 24 years (mean 11.7 years) were reviewed. Three patients were excluded. Seventy percent showed uptake at the conus medullaris. SUVs ranged from 1.33 to 4.2 (mean 2.14).
Conclusion
Low-level 18F-FDG uptake is common in the conus medullaris, represents normal distribution in children and should not be interpreted as metastatic disease to the CNS.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Nakamato Y, Tatsumi M, Hammoud D et al (2005) Normal FDG distribution patterns in the head and neck: PET/CT evaluation. Radiology 234:879–885
Shammas A, Lim R, Charron M (2009) Pediatric FDG PET/CT: physiologic uptake, normal variants, and benign conditions. Radiographics 29:1467–1486
Cook G, Fogelman I, Maisey M (1996) Normal physiological and benign pathological variants of 18-fluoro-2-deoxyglucose positron-emission tomography scanning: potential for error in interpretation. Semin Nucl Med 26:308–314
Thie JA (2004) Understanding the standardized uptake value, its methods and implications for usage. Nucl Med 45:1431–1434
Gilmore RL, Bass NH, Wright EA et al (1985) Developmental assessment of spinal cord and cortical evoked potentials after tibial nerve stimulation: effects of age and stature on normative data during childhood. Electroencephalogr Clin Neurophysiol 62:241–251
McCarville MB, Monu N, Smeltzer MP et al (2009) PET-CT of the normal spinal cord in children. Acad Radiol 16:881–885
Wolpaw JR (2006) The education and re-education of the spinal cord. Prog Brain Res 157:261–280
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Alazraki, A.L., Simoneaux, S.F. & Wyly, J.B. Normal conus medullaris FDG uptake in children. Pediatr Radiol 41, 1374–1377 (2011). https://doi.org/10.1007/s00247-011-2117-0
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00247-011-2117-0