Background: Image guidance for spine pain control procedures, including epidural steroid injection,
nerve root block, and facet block, can be performed with either computed tomography (CT) or
conventional fluoroscopy. CT has the advantage of improved anatomic localization and use of air for
contrast; however, there are concerns that CT leads to higher radiation dose and longer procedure
time.
Objective: To evaluate procedure time and radiation dose for multiple types of spine pain control
procedures performed under CT guidance.
Study Design: Retrospective evaluation.
Setting: Department of radiology in single academic medical center.
Methods: Institutional review board approval was obtained. We reviewed CT-guided spine procedures
performed over a 12-month period from January 2012 to December 2012. Procedure type, procedure
time, and dose-length product were recorded. Patient age and gender were recorded for each case;
additionally, demographic and medical history data were obtained for a sub-group of patients.
Results: Nine hundred ninety-four studies (performed in 699 patients) were reviewed, including 585
epidural steroid injections, 228 nerve root blocks, and 90 facet blocks. For all studies, procedure time
averaged 7:34 ± 5:05, and dose-length product averaged 75 mGy·cm ± 61. Additional medical history
(available for 483 patients) revealed high rate of obesity (body mass index [BMI] = 30 ± 6.8, with 76%
of patients overweight [BMI > 25] and 42% obese [BMI > 30]), and frequent medical comorbidities
(including hypertension [n = 179], diabetes [n = 101], renal failure [n = 30], and heart failure [n = 17]).
Limitations: This study was performed retrospectively, and limited to a single institution.
Conclusion: These findings add to the growing evidence that CT guidance is a safe and effective
technique for epidural steroid injection. These results further demonstrate that other spine intervention
procedures, including nerve root block and facet block, can also be performed under CT guidance with
short procedure time and reasonable levels of radiation exposure. This approach can be effectively
used in a patient population with a high rate of obesity and medical comorbidities.
Key words: Epidural steroid injection, nerve root block, facet block, CT-guidance, spine intervention,
radiation dose