Novel use of epidural catheter: Air injection for neuroprotection during radiofrequency ablation of spinal osteoid osteoma

Epidural Balloon Placement for Protection of the Spinal Canal During Cryoablation of Paraspinal Lesions

Ablation of paraspinal lesions close to the spinal canal and neuroforamina requires protective measures in order to protect the spinal cord and nerve roots. Various methods of protection have been previously described including infusion of saline and CO₂. Regardless, neuromonitoring should be adjunctively performed when ablating spinal lesions close to neuronal structures. Balloon protection has been previously described during ablation of renal masses. The benefit of balloon protection in paraspinal mass ablation is it physically displaces the nerve roots as opposed to CO₂ or saline which has the potential to insulate but because of its aerosolized or fluid nature may or may not provide definitive continuous protection throughout an ablation. This report details three paraspinal lesions, two of which were successfully ablated with the use of a balloon placed in the epidural space to provide protection to the spinal cord and nerve roots.

Air-blocking ablation of osteoid osteoma; a technical note

Osteoid osteoma accounts for approximately 10-12% of all benign bone tumors. Surgery was the treatment of choice for osteoid osteomas until percutaneous radiofrequency ablation (RFA) was introduced in 1992. Although RFA is generally considered curative in the treatment of osteoid osteoma, disease recurrence after ablation has been reported. We report a case in which RFA was delayed by the presence air surrounding the ablation probe. In this case, ablation could only be performed after the probe was removed and saline was injected through the introducer needle to displace the air. Air is reported to decrease radiofrequency energy transmission; a simple measure like injecting saline through an introducer could prevent such a complication. We also suggest that partial air in the ablation bed surrounding the ablation probe could decrease the energy transmission and may be one of the causes of early recurrences. Saline injection could be helpful in providing a more reliable environment for ablation.