Study compares radiation exposure associated with fluoroscopy-guided, CT-guided lumbar spinal injections

Fluoroscopy-guided lumbar spinal injections expose patients to less radiation than CT-guided injections, according to a new study published in Radiology. The fluoroscopy-guided injections, however, exposed physicians to more radiation. Patient outcomes were not impacted either way.

“We hypothesized that the radiation exposure for patients and interventional physicians is different between these two techniques,” wrote author Tobias J. Dietrich, of Orthopedic University Hospital Balgrist in Zurich, Switzerland, and colleagues. “Our second hypothesis was that patient clinical outcomes after imaging-guided lumbar spinal therapeutic injections with long-acting steroids may be influenced by the chosen imaging-guided technique.”

The authors studied data from 648 patients who received transforaminal epidural injections or facet joint injections from October 2009 to April 2016. Overall, patients who underwent fluoroscopy-guided epidural injections had a mean effective dose of 0.24 millisievert (mSv) ± 0.22 compared to a mean effective dose of 0.33 mSv ± 0.10 for patients who underwent CT-guided injections. Patients who underwent fluoroscopy-guided facet joint injections had a mean effective dose of 0.10 mSv ± 0.11 compared to a mean effective dose of 0.33 mSv ± 0.13 for patients who underwent CT-guided injections.

In addition, radiation exposure was higher for the interventionalist during fluoroscopy-guided epidural injections and fluoroscopy-guided facet joint injections than CT-guided injections.

“The participant radiation dose exposure was 1.4 times lower for fluoroscopy-guided compared with CT-guided lumbar transforaminal epidural injections and 3.3 times lower for fluoroscopy-guided compared with CT-guided lumbar facet joint steroid injections,” the authors wrote. “Conversely, the radiation exposure to the body and wrist of the interventional physicians was between 3.7 times and 10 times higher for fluoroscopy-guided compared with CT-guided lumbar spine injections. It must be noted that the amount of radiation dose exposure for participants was determined with multiplication of established conversion factors, whereas the amount of radiation dose exposure for interventionalists was measured with two independent active personal dosimeters.”

The authors were surprised to learn that clinical outcomes for patients were not impacted by the type of injection they received. Patients were evaluated up to one month following the procedure.