PET-CT of the Normal Spinal Cord in Children

Rationale and Objectives

The aim of this study was to assess the correlation between age and spinal cord metabolic activity in children using positron emission tomography–computed tomography.

Materials and Methods

The cohort included 128 children imaged from January 2003 through April 2007, excluding those with spinal disease. Using axial images, the fluorodeoxyglucose activity in the pons and three cervical, three thoracic, and two lumbar spinal cord levels was subjectively graded as minimal, moderate, or intense. From regions of interest at each level, the maximum standardized uptake value was determined. Patients were grouped by age: group 1, <5 years; group 2, ≥5 to <10 years; group 3, ≥10 to <15 years; and group 4, ≥15 to <22 years. Subjective grade and standardized uptake values were compared at each level and for each level between age groups. The α level was set at 0.0046 on the basis of Bonferroni's correction for multiple comparisons.

Results

There were 16 patients in group 1, 19 in group 2, 33 in group 3, and 60 in group 4. Subjective grades and standardized uptake values were higher in the pons, midcervical, and low thoracic areas than elsewhere in all age groups. Subjective grades significantly increased with age in the cervical and thoracic cord (P < .0005). Standardized uptake values in the pons and all cord levels significantly increased with increasing age (P ≤ .0008).

Conclusions

In children, the metabolic activity of the spinal cord increases with age. On positron emission tomography, the cord can appear intensely avid in the midcervical and low thoracic areas.

Key Words: Positron emission tomography–computed tomography, spinal cord, children