Efficacy and safety of magnetic resonance-guided focused ultrasound treatment for refractory chronic pain of medial knee osteoarthritis.

OBJECTIVE: To elucidate the efficacy and safety of MRgFUS in the treatment for refractory pain derived from medial knee OA. METHODS: Twenty patients with medial knee OA eligible for total knee arthroplasty were included in this prospective, non-controlled study (UMIN000010193). MRgFUS treatment was provided at the site of most severe tenderness around the medial femorotibial joint of each patient under real-time monitoring of temperature. The goal temperature of the targeted bone surface was 55 °C. Numerical rating scale (NRS) worst pain scores, Western Ontario and McMaster Universities osteoarthritis index (WOMAC) scores, EuroQol 5 dimensions index (EQ-5D) scores and pressure pain threshold (PPT) were evaluated before treatment (baseline) and at 1 week and 1, 3, 6, and 12 months post-treatment, respectively. Complications and adverse events were also assessed clinically and radiographically. RESULTS: Treatment response (a 50% or greater decrease in NRS score) was seen in 14 patients (14/19, 73.7%) at 12 months post-treatment. Mean NRS score rapidly decreased at 1 month after treatment and continued to decline through the following 12 months. At final follow-up, mean NRS score was 3.2 ± 1.9, significantly lower than at baseline (p = 0.0013). Mean WOMAC and EQ-5D scores also improved significantly from 1 month after treatment. Fifteen patients showed significant sustained increases in PPTs at the sites of most severe tenderness. No serious adverse events were observed during and after treatment. CONCLUSIONS: MRgFUS treatments were effective not only for managing refractory pain, but also for improving physical functions without adverse events in elderly patients with medial knee OA.

Effects of MRgFUS Treatment on Musculoskeletal Pain: Comparison between Bone Metastasis and Chronic Knee/Lumbar Osteoarthritis.

Local bone denervation by magnetic resonance-guided focused ultrasound (MRgFUS) is a promising tool for alleviation of pain in patients with painful bone metastasis (BM). Considering the underlying mechanism of pain alleviation, MRgFUS might be effective for various bone and joint diseases associated with local tenderness. This study was conducted to clarify the therapeutic effect of focused ultrasound in patients with various painful bone and joint diseases that are associated with local tenderness. Ten patients with BM, 11 patients with lumbar facet joint osteoarthritis (L-OA), and 19 patients with knee osteoarthritis (K-OA) were included. MRgFUS treatment was applied to the bone surface with real-time temperature monitoring at the target sites. Pain intensity was assessed using a 100 mm numerical rating scale (NRS) at various time points. Pressure pain threshold (PPT) was evaluated on the sonication area and control sites. Compared to baseline, the pain NRS scores significantly decreased in all groups 1 month after treatment, and PPT at the treated sites significantly increased in all groups 3 months after treatment. The percentage of patients who showed a ≥ 50% decrease in pain NRS scores at 1 month after treatment was 80% in BM, 64% in L-OA, and 78% in K-OA groups. PPTs were significantly higher after treatment at all evaluation time points. This study indicated that MRgFUS is effective in reducing pressure pain at the site of most severe tenderness in patients with painful bone and joint diseases. Treatment response was comparable between patients with BM, L-OA, and K-OA.

Automated volumetric breast density estimation out of digital breast tomosynthesis data: feasibility study of a new software version.

BACKGROUND: A new software version of VolparaDensity (Volpara Algorithm version 1.5.1) is capable of calculating volumetric breast density (VBD) using either full-field digital mammography (FFDM) or digital breast tomosynthesis (DBT) images. In this preliminary study, we evaluated the feasibility and consistency of this new automated software. FINDINGS: Raw data from both DBT and FFDM were acquired from women breast cancer screening at our institution between April and August 2015 using. The DBT and FFDM images obtained under a single compression were collected and VBD was measured using fully automated software. A paired t test was used to analyze differences in the VBD calculated from paired FFDM and DBT images. The correlation coefficient (R value) was calculated and p < 0.05 was considered significant. Dualmodality images were acquired in 160 women; VBD data were available for all but one. There was a significant difference in the VBD of individual breasts calculated from DBT and FFDM and when data were compared per case (<0.001 and p = 0.006, respectively). There were very good to excellent correlations between data from FFDM and from DBT (R = 0.78, p < 0.0001; per breast, R = 0.89, p < 0.0001, per case, R = 0.91, p < 0.0001). CONCLUSIONS: VBD from DBT was well correlated to that from FFDM, though significant differences were observed between the two.

MR-guided focused ultrasound for the novel and innovative management of osteoarthritic knee pain.

BACKGROUND: Severe knee pain associated with osteoarthritis (OA) is one of the most common and troublesome symptoms in the elderly. Recently, local bone denervation by MR-guided focused ultrasound (MRgFUS) has been demonstrated as a promising tool for pain palliation of bone metastases. The purpose of this study was to develop a novel treatment for knee OA using MRgFUS, and to validate its safety and efficacy. METHODS: Eight patients with medial knee pain and eligible for total knee arthroplasty were included. MR-guided focused sonication treatments were applied to bone surface just below the rim osteophyte of medial tibia plateau with real-time monitoring of the temperature in the target sites. The pain intensity during walking was assessed on a 100 mm visual analog scale (VAS) before and after treatment. Pressure pain thresholds (PPTs) were also evaluated over several test sites adjacent to the sonication area and control sites one month after treatment. RESULTS: Six patients (75%) showed immediate pain alleviation after treatment, and four of them demonstrated long-lasting effect at 6-month follow up (mean VAS reduction; 72.6%). In responders, PPTs in medial knee were significantly increased after treatment (Median; pre- 358 kpa vs post- 534 kpa, p < 0.0001). There were no adverse side effects or complications during and after treatment. CONCLUSIONS: These initial results illustrate the safety and efficacy of the newly developing MRgFUS treatment. Significant increase of PPTs on treated area showed successful denervation effect on the nociceptive nerve terminals. MRgFUS is a promising and innovative procedure for noninvasive pain management of knee OA. TRIAL REGISTRATION: Trial Registration: UMIN000010193.