Changes in¹⁸F-Fluorodeoxyglucose Uptake in the Spinal Cord in a Healthy Population on Serial Positron Emission Tomography/Computed Tomography

Abstract

We aimed to determine the changes in 18F-fluorodeoxyglucose (FDG) uptake in the spinal cord on two serial positron emission tomography/computed tomography (PET/CT) scans in a healthy population. We retrospectively enrolled healthy people who underwent PET/CT twice for cancer screening. We excluded those who had degenerative vertebral disease, neurologic disease, or a history of a vertebral operation. The standardized uptake value (SUVmax) of the spinal cord of each mid-vertebral body was obtained by drawing a region of interest on an axial image of PET/CT. For analysis, the cord-to-background ratio (CTB) was used (CTB=SUVmax of each level/SUVmax of L5 level). Differences in pattern, sex, age, and intervals of the two serial PET/CT scans were analyzed. A total of 60 PET/CT images of 30 people were analyzed. The mean interval between the two PET/CT imaging studies was 2.80±0.94 years. On the follow-up PET/CT, significant change was shown only at the level of the C6 and T10 vertebrae (p<0.005). Mean CTB showed a decreasing pattern from cervical to lumbar vertebrae. There were two peaks at the lower cervical level (C4-6) and at the lower thoracic level (T12). Neither sex nor age significantly affected CTB. The FDG uptake of the spinal cord changed significantly on follow-up PET/CT only at the level of the C6 and T10 vertebrae. This finding is valuable as a baseline reference in the follow-up of metabolic changes in the spinal cord.

Positron Emission Tomography in Spinal Cord Disease

“…Strictly speaking, these data do not qualify as normative data derived from healthy volunteers. Nevertheless, Flanagan et al found good agreement with other reports on FDG uptake in the spinal cord of healthy volunteers, [4][5][6][7] implying that using disease-free cord segments as an internal reference may be reasonable. The choice of the maximum SUV for FDG uptake measurement not only is convenient but also has the advantage of reproducibility.…”

Tumor to cervical spinal cord standardized uptake ratio (SUR) improves the reproducibility of 18F-FDG-PET based tumor segmentation in head and neck squamous cell carcinoma in a multicenter setting

“…This can introduce uncontrollable variations in FDG-uptake and can result in a poor inter-patient reproducibility of the internal standard. In contrast, FDG-uptake in the cervical spinal cord has both little inter-patient variability, is stable over time and is not influenced by muscular activity [14,15]. The cur-rent analysis shows that the cervical spinal cord has equivalent FDG-uptake as the mediastinal blood pool.…”

“…An alternative structure located in the head and neck area that may be used as an internal standard is the cervical spinal cord. Literature reports that FDG-uptake in the cervical spinal cord has both little interpatient variability and is stable over time [14,15].…”

Primary Leptomeningeal Lymphoma Presenting as Low Back Pain and Dementia: A Case Report

“…He sought for another neurologist's opinion. On EEG, he had good baseline activity (11)(12)(13) and no epileptiform changes were seen. On whole body CT scan with contrast, it showed ventriculomegaly with leptomeningeal enhancement from cranial meninges down to the lumbosacral spine ( Figure 2).…”

“…A normal PET scan(A) showing normal uptake of the spine[11] as compared to patient WDR who has increased metabolic activity from the cervical to the lumbar cord (B), most intense on the cauda equina (C).…”