90Y Radiosynovectomy in Persistent Synovitis Caused by Knee Replacement: Long-Term Outcome

a.sfakia shared this article with you from Inoreader 90Y Radiosynovectomy in Persistent Synovitis Caused by Knee Replacement: Long-Term Outcome Via Clinical Nuclear Medicine - Published Ahead-of-Print Introduction After knee replacement, therapy resistant, persistent synovitis is a common issue, which causes effusion and pain, and leads to loosing. It has been hypothesized that radiosynovectomy (RSO) is useful in these patients. Materials and Methods A cohort of 55 patients with 57 knee replacements and persistent synovitis underwent RSO using 4.9 ± 0.24 mCi (182 ± 9 MBq) of 90Y-citrate. The number of RSOs ranged from 1 to 4. Bone scans before and 3 months after every RSO were performed. Long-term follow-up ranged from 0.8 to 7.6 years with a mean of 23.2 months. For qualitative analysis, an established 4 steps scoring was used. For quantification, the uptake was determined within the 99mTc-MDP scintigraphy blood pool phase before and after therapy. Results Long-term response was in 27% with excellent, 24% good, 30% weak, and 20% no response. The duration of response was 12.0 ± 12.0 months (maximum, 54 months). In patients with repeated treatment, the effect after the first therapy was lesser than in patients who received a single treatment in total. However, 3 months after the last RSO, patients with repeated treatment showed a similar effectiveness than single treated patients. At the end of long-term follow-up, patients with repeated RSOs had a higher effectiveness at similar duration response. In bone scan, 65% of patients showed a reduction of uptake. When comparing subjective and objective response, 78% of patients showed a concordance in both symptoms and scintigraphy. Pilot histological analysis revealed that the synovitis is triggered by small plastic particles. Conclusions We concluded that RSO is an effective therapy in patients with knee replacement and persistent synovitis with high long-term response. Repeated treatment leads to a stronger long-time response. Received for publication August 21, 2020; revision accepted October 2, 2020. K.L. and M.B. equally contributed. Conflicts of interest and sources of funding: K.L. is a consultant of Serene LCC. M.B. declares that no funding was applicable. The authors declare that no ethics approval and consent to participate were necessary. The authors have consent of publication for their data. The used data and materials are available and can be requested. The licenses of used software are available. Correspondence to: Knut Liepe, MD, PhD, MHBA, Department of Nuclear Medicine, Klinikum Frankfurt (Oder), Muellroser Chaussee 7, 15236 Frankfurt (Oder), Germany. E-mail: knut.liepe@klinikumffo.de. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved. View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.