Potential usefulness of 18F-2-fluoro-deoxy-D-glucose positron emission tomography in cervical compressive myelopathy

Study Design. This case study describes the usefulness of high-resolution F-18-2-fluoro-deoxy-D-glucose ((18)FDG)-positron emission tomography (PET) for metabolic neuroimaging of the cervical spinal cord in patients with compressive myelopathy. Objective. To examine whether (18)FDG-PET imaging could visualize deterioration of cervical spinal cord function associated with a variable degree of compression and to determine its potential usefulness during assessment of myelopathy. Summary of Background Data. A few studies have described the use of (18)FDG-PET imaging in cervical cord diseases, but visualization of the cervical spinal cord before and after surgical decompression for compressive myelopathy has not been reported. The potential usefulness of (18)FDG-PET imaging for assessment of the function of compressed cervical cord has not been discussed previously. Methods. An (18)FDG-PET scan was performed before and after surgery in seven patients with cervical compressive myelopathy. The correlation between the metabolic rate of glucose of the cervical spinal cord and neurologic scores was evaluated. The metabolic rate of glucose in different vertebral levels was also measured. Results, Preoperative metabolic rate of glucose was high in two patients but low in the other five. At the time of the second postoperative examination, metabolic rate of glucose was higher in six of the seven patients, and the increase was associated with neurologic improvement. Use of (18)FDG was not related to changes in signal intensities on T2-weighted magnetic resonance images. The metabolic rate of glucose decreased at the affected vertebral level in four patients, increased in two, and did not change in one, relative to the unaffected levels. Conclusions. High-resolution (18)FDG-PET neuroimaging may provide clinically useful qualitative and quantitative estimation of impaired metabolic activity of the compromised cervical spinal cord in compressive myelopathy. (18)FDG-PET images may also offer additional information related to neuronal dysfunction induced by mechanical compression.