A technical complication of radiosynovectomy in the ankle: leakage to distal tibiofibular syndesmosis

The EANM guideline for radiosynoviorthesis

Purpose

Radiosynoviorthesis (RSO) using the intraarticular application of beta-particle emitting radiocolloids has for decades been used for the local treatment of inflammatory joint diseases. The injected radiopharmaceuticals are phagocytized by the superficial macrophages of the synovial membrane, resulting in sclerosis and fibrosis of the formerly inflamed tissue, finally leading to reduced joint effusion and alleviation of joint pain.

Methods

The European Association of Nuclear Medicine (EANM) has written and approved these guidelines in tight collaboration with an international team of clinical experts, including rheumatologists. Besides clinical and procedural aspects, different national legislative issues, dosimetric considerations, possible complications, and side effects are addressed.

Conclusion

These guidelines will assist nuclear medicine physicians in performing radiosynoviorthesis. Since there are differences regarding the radiopharmaceuticals approved for RSO and the official indications between several European countries, this guideline can only give a framework that must be adopted individually.

Remote arterial vasculitis as a possible complication of Phosphorus-32 Radiosynovectomy

Patients with hemophilia suffer from repeated episodes of hemarthrosis leading to chronic inflammation and synovitis. Radiosynovectomy is an effective nonsurgical modality that can reduce inflammation, pain, and hemarthrosis in such cases. We describe an adolescent male with severe Hemophilia A, who developed arterial vasculitis and perivasculitis targeting the brachiocephalic, right common carotid, and right subclabvian arteries occurring within few days after difficult Phosphorus-32 radiosynovectomy, possibly as a complication of the procedure. Despite prophylaxis with recombinant FVIII therapy, he developed chronic synovitis and underwent radionuclide synovectomy with P-32 injection to the left ankle and right knee. Five days later, he developed pain in the lower right neck and right upper chest. Computed tomography and magnetic resonance imaging and angiography demonstrated inflammation involving the arteries of the right thoracic inlet. Geiger-Mueller meter indicated increased radioactivity not only in the left ankle and right knee but also in the right upper chest. Detection of radioisotope at the right thoracic inlet corresponding to the area of vasculitis was indicative of likely deposition of the P-32 isotope in an area exposed to maximum cardiac output and increased blood flow, leading to subclavian, carotid, and innominate arteritis with surrounding edema.

Current role for radioisotope synovectomy

Radioisotope synovectomy has been extensively used to treat patients with chronic inflammatory joint disease but has moved to a less prominent position since the introduction of new and highly effective drugs. Remaining indications are refractory synovitis, pigmented villonodular synovitis as an adjunct to surgery, and hemophilic arthropathy. The three main radioisotopes used are yttrium-90, rhenium-186, and erbium-189. Radioisotope synovectomy should be performed only by highly experienced professionals, to minimize the risk of injection-related complications. The available safety data, in particular regarding the risk of malignancy, are reassuring. The efficacy of yttrium-90 in chronic inflammatory joint disease remains controversial.

Safety of radiation exposure after radiosynovectomy in paediatric patients with haemophilia

Many paediatric patients with haemophilia who might benefit from radiosynovectomy (RS) for the control of synovitis do not undergo the procedure as there is controversy in the literature regarding the safety of radiation exposure after two cases of acute lymphocytic leukaemia in children with haemophilia treated with (32) P RS were reported. The purpose of this review was to analyse the safety of RS in paediatric patients with haemophilia and provide a risk-benefit assessment, which practitioners could apply to their patients. Children undergoing knee RS receive a radiation dose of approximately 0.74 mSv (90 megabecquerels-MBq) and elbow and ankle RSs a dose of approximately 0.32 mSv (30-40 MBq). The radiation dose from natural sources is approximately 2 mSv and the recommended limit for patients (apart from natural sources) is 1 mSv per year. The lifetime cancer risk increases about 0.5% per 100 mSv per year. Considering the risks and benefits of RS, the authors recommend that clinicians consider this procedure in children with inhibitors or in patients without inhibitors when bleeding is recurrent and persistent despite aggressive factor replacement.