Ultrasound-Guided Focused Ultrasound Treatment for Painful Bone Metastases: A Pilot Study

Focused ultrasound (FUS) for palliation of bone metastases has typically been performed under magnetic resonance guidance. To address limitations of this approach, this pilot study evaluated a stand-alone, portable FUS device guided by diagnostic ultrasound alone (ultrasound [US]-guided FUS). Nine patients were treated; safety and efficacy were assessed for 10 d after the procedure, and medical charts were evaluated to assess durability of pain response. The procedure was safe and tolerable, with four patients reporting minor skin-related irritations. Average pain score decreased from 6.9 at baseline to 3.2 at day 10; analgesic use on average also decreased from baseline to day 10. Six patients had durable pain relief as assessed after the follow-up period. Our study provides evidence that US-guided FUS is a safe, tolerable and versatile procedure. It appears to be effective in achieving durable pain response in patients with painful bone metastases. Further research is required to refine the technology and optimize its efficacy.