PET/MRI reveals more than just nerve impingement causing sciatica

Radiology and orthopedics researchers at Stanford have shown the prowess of nuclear imaging for identifying the specific source(s) of pain and reduced mobility in patients with chronic sciatica, a common low-back condition notorious for evading such pinpointing.

The Journal of Nuclear Medicine published the team’s findings online Nov. 2.

Senior study author Sandip Biswal, MD, and colleagues performed PET/MRI using the radiotracer fluorodeoxyglucose (18F-FDG) on nine symptomatic patients and five healthy volunteers.

In all nine patients, the researchers recorded significantly increased FDG uptake in detected lesions correlating with pain and related symptoms.

Further, along with finding FDG-avid lesions in impinged nerves of the lumbar spine—no surprise—they also observed uptake activity that associated with non-spinal causes. These included facet-joint degeneration and pars defect, along with a presumed scar neuroma.

“The feasibility of 18F-FDG PET/MRI for diagnosing pain generators in chronic sciatica has been demonstrated, revealing various possible etiologies,” Biswal et al. report.

Sciatica, which frequently radiates pain and reduced mobility into the buttocks and legs, can be painful to the point of debilitating. Without surgery or another intervention, serious cases can lead to paralysis of the lower extremities and urinary and/or fecal incontinence.