STAR RF-ablation for the management of painful vertebral bone metastases
05 March 2019 (online)
Osseous metastatic lesions are the most frequent complication of malignant tumors and associated with severe pain and pathologic fractures. The use of radiofrequency ablation (RFA) is an alternative to local radiotherapy and provides the advantage to augment the destroyed bone by cement during the same procedure.
52 patients were treated at 2 academic centers in the Rhine-Main-Area. Fluroscopy guided t-RFA was performed with the STAR Tumor Ablation System (Merit Medical, USA) which includes a robust articulating, navigational bipolar electrode containing two active thermocouples (TC) positioned to permit real time monitoring of the peripheral edge of the ablation zone to determine size of ablation. Pre-procedural planning was performed based on cross-sectional imaging to determine number of targeted ablations based on lesion size & thermal distribution curves. Treatment was controlled by adjusting power while monitoring TC temperature in-situ. All patients received vertebral augmentation with RF warmed high viscosity cement after use of radiofrequency via the same guiding cannula. In all patients pain was assessed by Visual Analogue Scale (VAS) preoperatively, 1 week after the procedure and 6 months after treatment.
Lesion etiology included a wide variety of metastatic lesions (lung, renal cell, breast, lymphoma, multiple myoloma, bladder, prostate melanoma, liposarcoma) Fluoroscopic guided RFA procedures were successfully performed in all 52 patients. All patients reported pain relief. Average VAS improved from 7.8 pre to 4.4one week post t-RFA (p < 0.05). and 3,0 after 6 months of the procedure (p < 0.05). No device related adverse events were reported. Post-ablation histology confirmed metastatic lesions were necrotic in the ablation zone.
The STAR Tumor Ablation System, an innovative bipolar RF device, purpose built for targeted ablation of spinal malignant lesions, was safely and effectively used in the navigation and targeted RFA of spinal bone metastases.