Background and aims Fluoroscopy-guided epidural steroid injections (FESI) are widely used for managing low back pain (LBP). There is lack of data on cumulative radiation dose in patients receiving more than one FESI. To determine cumulative radiation dose for three consecutive FESI. To find factors that correlate with higher dose area product (DAP) or longer fluoroscopy time (FT).

Methods Three groups of patients: LBP duration for 2, 5 and more than 5 years. One-way ANOVA and independent t-test used to compare FT.

Results 48 females and 8 men (mean age 56), mean LBP 4.6 years. Mean cumulative DAP 872.57cGycm2 (SD 275.53), mean FT 70.39s (SD 17,69 s); strong positive correlation between FT and DAP (r=0.755; p=0.01). Mean FT during 1st procedure 24.5s; 2nd 23.6s; 3rd - 22.3s. Mean DAP during 1st procedure 294,67cGycm2; 2nd 287,79cGycm2; 3rd 296,61cGycm2. FT and DAP positively correlated in each group, 1st ESI time ρ 0,750; 2nd 0,797; 3rd 0,682 (p=0.01). First FT was longer in LBP for more than 5 years (p=0.05) n=13 (mean 29.38s); LBP less 1 year n=13 (mean 21s) and LBP from 1 to 5 years n=30 (mean 21.27s). Mean DAP was higher during three procedures and LBP longer than 5 years (p=0.05).

Conclusions FT is in uphill linear relationship with DAP. Mean cumulative dose is 57 times lower than radiation dose for FESI allowed by Society of Interventional Radiology of Europe. Patients with longer LBP have longer FT and higher DAP, probably due to severe degenerative spinal lesions.