Dr Anita Lee and Dr Kevin Pile, authors of 'Disease modifying drugs in adult rheumatoid arthritis', comment:
Intra-articular instillation of a radioactive isotope, to perform a non-surgical synovectomy of persistently inflamed solitary joints, has been proposed as an adjunctive therapy for rheumatoid arthritis and spondylo arthritis. The theoretical ideal agent is a beta-emitter that can be delivered in a colloidal or particulate form, that is small enough to be phagocytosed by the macrophage synovial lining cells, yet large enough to reduce systemic absorption. In practice radiosynovectomy has primarily been trialled in knee synovitis so as to ensure intra-articular placement. Yttrium 90 and Dysprosium 165 are available for intra-articular use in Australia. Holmium 166 is a short half-life beta-emitter that has been used overseas.
Despite its theoretical utility, a systematic review of Yttrium 90 radiosynovectomy of the knee in patients with rheumatoid arthritis found that there was little support for its use, in comparison to saline or corticosteroid injections.1
