Predictive Value of Epidural Gas Spread Pattern Following Transforaminal Ozone Injection for Clinical Outcomes in...

Percutaneous interventions for cervical radiculopathy (CR) show variable efficacy, lacking reliable prognostic predictors. We hypothesized that epidural gas spread patterns during CT-guided ozone injection-using ozone as a native contrast agent-can functionally assess epidural adhesions and predict clinical outcomes.

This prospective, observational cohort study enrolled 185 patients with single-segment CR completing a 6-month follow-up. During CT-guided transforaminal ozone injection, epidural gas spread was evaluated before administering the therapeutic dose. Patients were classified into Good Spread (GS; n=98) or Poor Spread (PS; n=87) groups. Primary (Neck Disability Index, NDI) and secondary (Visual Analog Scale, VAS) outcomes were assessed at baseline and multiple post-intervention time points up to 6 months.

Both groups showed significant NDI and VAS improvements from baseline (p<0.001). However, the GS group exhibited significantly greater improvement at all follow-ups (p<0.01). At 6 months, treatment success (≥50% NDI reduction) was 89.8% in the GS group versus 44.8% in the PS group (p<0.001). Multivariate analysis identified a good spread pattern (OR=9.80, 95% CI: 4.51-21.30; p<0.001) and shorter symptom duration (OR=4.50, p=0.004) as independent predictors of treatment success.

This study suggests that the epidural diffusion pattern of ozone gas during CT-guided transforaminal injection may be a useful predictor for clinical outcomes in CR. These findings highlight the potential role of epidural adhesions in treatment response. However, due to the single-center observational design, our findings may lack broad generalizability, and future randomized controlled trials are necessary to confirm these results.