Technical Feasibility and Outcome of Cryoablation of Aneurysmal Bone Cysts in Pediatric Patients.

PURPOSE: To evaluate the clinical and imaging outcome of aneurysmal bone cysts (ABC) in children using percutaneous cryoablation as the sole treatment.

MATERIAL AND METHODS: This retrospective study included 7 children mean age 8.7 years (range 3.0 to 11.9 years) who received at least one cryoablation for ABC. Cryoablation needles were placed and guided by computer tomography (CT). Imaging follow-up and clinical examination were performed by radiography 1 and 6 months and magnetic resonance imaging (MRI) 3 and 12 months after the procedure. Additional cryoablation was done in case of MRI-detected recurrence. Data were analyzed by anatomical location, measurement of the lesion volume, numbers of intralesional cysts, grade of mineralization (5-point Likert scale), pain (0 none to 4 severe) and grade of fluid- fluid levels (FFL, 4-point Likert scale).

RESULTS: 14 cryoablations were performed. Patients showed volume reduction, with one showing a complete response and six showing partial response. Following treatment, there was a substantial reduction in lesion volume compared to baseline, leading to a mean volume decrease of 81.9% (range 66.8% to 100%). The grade of mineralization (3.2 ± 1.2 after therapy vs 1.1 ± 0.3 at baseline), grade of FFL (1.6 ± 0.5 after therapy vs 3.4 ± 1.1 at baseline) and pain (0.29 +- 0.4 after therapy vs 1.86 +- 0.7 at baseline) significantly improved after therapy (all p < 0.05). One severe adverse event occurred.

CONCLUSIONS: Cryoablation is an effective treatment option for ABC in children. Further research is needed to compare it with other techniques.