Abstract
This case report is the first clinical trial of non-invasive thermal ablation using magnetic resonance-guided focused ultrasound (MRgFUS) for the palliation of painful bone metastasis.
A 60-year-old woman suffering from painful bone metastasis at the ilio-sacral joint had been treated with external beam radiation and radiofrequency ablation. MRgFUS treatment for the bone metastasis was conducted using a focused ultrasound phased array system (ExAblate® 2000, InSightec Ltd.), integrated with a magnetic resonance imaging (MRI) scanner (GE 3.0-T MRI). During the treatment, the site of each sonication and the temperature elevation in the tissue adjacent to the targeted bone were monitored in real time. The Efficacy of MRgFUS was evaluated using a numeric rating scale (NRS), the brief pain inventory (BPI), and medication level questionnaires before treatment, 3 days, 2 weeks, 1 month, and 3 months after treatment. The total length of the treatment was 147 min. Sonication was done 15 times, with an average sonication energy of 441.3 J. The NRS score of the metastatic lesion decreased from 7 to 0 two months after treatment. The BPI score showed that pain did not interfere with the patient's activities of daily life 3 months after treatment. No treatment-related adverse events occured.
These clinical results indicate that MRgFUS may be useful non-invasive palliative treatment for the patients with bone metastases in the future.
