Visualization of Distal Spinal Cord on F-18 FDG PET/CT

Abstract

Mild to moderate distal spinal cord F-18 FDG uptake on PET/CT is a common normal variant, more common in younger age and in patients with lower glucose levels. It likely represents metabolic activity of lumbosacral plexus nerve cell bodies.

Clinical Significance of Incidental Focal 18F-FDG Uptake in the Spinal Cord of Patients with Cancer

“…Do et al reported a significant increase in cord uptake at the T11-T12 vertebral body levels [4]. Greenspan et al analyzed the physiologic uptake of the T11-L1 spinal cord in subjects without spinal cord metastasis and reported that the highest maximal SUV was 3.7 [3]. Our study also revealed that T12 and L1 were the most common sites of 18 F-FDG cord uptake, consistent with previous studies.…”

“…However, some sites, such as the ovary and stomach, have normal physiologic uptake, which makes interpretation difficult and can lead to unnecessary, additional tests. Recently, a few studies have reported normal physiologic uptake by the spinal cord and highlighted the need to avoid misdiagnosis of malignant involvement for 18 F-FDG cord uptake [3][4][5]. However, such reports have investigated only spinal cord uptake without evidence of spinal cord malignancy or metastasis.…”

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.…”

[18F]FDG uptake of the normal spinal cord in PET/MR imaging: comparison with PET/CT imaging

“…So far, the [ 18 F]FDG uptake in normal and diseased spinal cord was evaluated in PET/CT studies [2][3][4][10][11][12][13][14][15][16]. It is recognized that clinical PET/MRI could be advantageous with respect to PET/CT for assessment of spinal cord diseases [1].…”