Purpose: To prospectively evaluate the feasibility, safety, and clinical utility of bone radiofrequency (RF) ablation with real-time monitoring of the spinal canal temperature for the treatment of spinal tumors adjacent to the spinal cord.
Materials and methods: Our Institutional Review Board approved this study. Patients gave informed consent. The inclusion criteria were (a) a painful spinal metastasis and (b) a distance of 1 cm or less between the metastasis and the spinal cord. The thermocouple was placed in the spinal canal under CT fluoroscopic guidance. When the spinal canal temperature reached 45 degrees C, RF application was immediately stopped. RF ablation was considered technically successful when the procedure was performed without major complications. Clinical success was defined as a fall in the visual analogue scale score of at least 2 points.
Results: Ten patients with spinal tumors measuring 3-8 cm (mean, 4.9 +/- 1.5 cm) were enrolled. The distance between the tumor and the spinal cord was 1-6 mm (mean, 2.4 +/- 1.6 mm). All procedures were judged technically successful (100%). The spinal canal temperature did not exceed 45 degrees C in 9 of the 10 patients (90%). In the remaining patient, the temperature rose to 48 degrees C, resulting in transient neural damage, although RF application was immediately stopped when the temperature reached 45 degrees C. Clinical success was achieved within 1 week in all patients (100%).
Conclusion: Bone RF ablation with real-time monitoring of the spinal canal temperature is feasible, safe, and clinically useful for the treatment of painful spinal metastases adjacent to the spinal cord.