Efficacy of Magnetic Resonance‐guided Focused Ultrasound Surgery for Bone Metastases Pain Palliation

Magnetic resonance‐guided focused ultrasound surgery (MRgFUS) is a novel treatment method that achieves non‐invasive thermal ablation by focusing many ultrasound waves on a target tissue with real‐time monitoring of the location and temperature of the target during the procedure. We investigated the palliative effect on pain and safety of MRgFUS in painful bone metastases. Six patients (mean age, 65.8 years) who met eligibility criteria for the clinical study approved by our Institutional Ethics Committee based on the cooperative protocol were treated with MRgFUS. Targeted sites included the sacrum (n = 1), ilium (n = 2), scapula (n = 2), and femur (n = 1). The mean follow‐up period was 9.2 months. All procedures were performed as a single‐session treatment using the treatment system that is integrated into the patient table of a magnetic resonance image (MRI) scanner. Endpoints were change in the intensity of pain due to bone metastases from before to after the treatment, as measured on a numerical ratin...