Background: Epidural steroid injections (ESIs) are a common method for treating lower back
pain, which is one of the most prevalent health-related complaints in the adult U.S. population.
Although the safety of CT-guided ESIs has been extensively studied in adults, there is limited data
concerning the procedure’s safety profile in an older patient population.
Objective: This retrospective study analyzed safety data among a single-center cohort of patients
> 65 years-old who received one or more CT-guided interlaminar ESIs from 2012 to 2015.
Study Design: An Institutional Review Board (IRB)-approved retrospective chart review.
Setting: University hospital center.
Methods: A total of 688 CT-guided ESI procedures were evaluated and a linear regression analysis
was conducted to examine the relationship between dose length product (DLP), body mass index
(BMI), procedure duration, and kVp/mA settings. Further analysis was performed on a sample of
long procedure time, average-DLP and high-DLP procedures.
Results: Average age was 75.77 years, with 44% having a BMI > 30. The mean DLP was 55.58
mGy x cm and the mean procedure duration was 5.94 minutes. All procedures were technically
successful and no complications were observed during or after any of the procedures, including at
one-month follow-up office visits. The kVp and mA settings were the strongest predictors of DLP,
followed by procedure time. The high-DLP cases had a greater number of needle placement series,
more intervertebral disc spaces included in each planning series and higher machine settings (kVp
120; mA 87.5) than the average-DLP cases (kVp 100; mA 49.9).
Limitations: This study is limited by its retrospective design.
Conclusion: CT-guided interlaminar ESIs can be performed safely, with low procedure times,
relatively low DLP’s and without complications in an older patient population.
Key words: Epidural steroid injection, interlaminar approach, CT-guidance, older adults, back
pain, lumbar spine, thoracic spine, cervical spine, dose length product, radiation exposure
Radiation Dose for 345 CT-Guided Interlaminar Lumbar Epidural Steroid Injections