ETD

• cryoablation
• interventional radiology
• osteoid osteoma
• percutaneous thermal ablation
• radiofrequency ablation

Purpose: This study aims to evaluate and compare the safety and clinical effectiveness of radiofrequency ablation (RFA) and cryoablation in the treatment of osteoid osteoma (OO), based on a retrospective analysis of patients treated at two major interventional radiology centers in Italy.

Materials and Methods: The study reviews a total of 80 patients with radiologically and clinically confirmed OO treated with percutaneous ablation between January 2016 and June 2025. Of these, 71 patients with complete pre- and post-treatment follow-up were included in the retrospective analysis. The cohort comprised 57/71 (80.2%) patients treated with RFA and 14/71 (19.8%) with cryoablation. Baseline data included age, gender, lesion site and size, pain intensity on the visual analog scale (VAS), procedural details, complications, recurrence, time to recurrence, and retreatment outcomes. Clinical success was defined as the complete resolution of pain after the procedure, and safety was assessed by the incidence and severity of peri- or post-procedural complications. Statistical comparisons were made using Welch’s t-test, Mann–Whitney U test, Fisher’s exact test, and point-biserial correlation, with significance set at p < 0.05.

Results: The mean patient age was 21.5 ± 10.1 years (range = 6-56 years), and the mean lesion diameter was 7.4 ± 3.8 mm. Cryoablation was preferentially applied to larger lesions (11.1 ± 5.0 mm) compared with RFA (6.5 ± 3.0 mm; p = 0.022). Clinical success was achieved in 94.7% of RFA and 100% of cryoablation cases (p > 0.99). Recurrence occurred in 7/71 patients (9.9%), with no significant difference between treatment modalities (p > 0.99). Retreatment was performed in all recurrent cases and resulted in complete symptom resolution in 5/7 patients (71.4%). When outcomes following retreatment were included, the overall clinical success rate increased to 97.2%. Minor complications (CIRSE complication grading </= 3) were observed in 3 RFA procedures (4.2%) and none following cryoablation (p = 0.57); no major adverse events occurred in either group.

Conclusion: Both RFA and cryoablation proved safe and effective in treating OO, achieving high clinical success with minimal recurrence and complications. Cryoablation, used for larger or complex lesions, performed comparably to RFA, supporting its role as a reliable alternative in modern interventional radiology.