Samarium-153-particulate hydroxyapatite radiation synovectomy: biodistribution data for chronic knee synovitis.

摘要

Biodistribution data for the radiation synovectomy agent samarium-153-particulate hydroxyapatite (153Sm-PHYP) are reported. METHODS: Mean extra-articular activity accumulation calculated from serial whole-body scans in 13 patients treated for chronic knee synovitis was 0.74% of injected activity (range 0%-3%). RESULTS: In four patients (31%), activity was noted in the lung (mean 0.68% of injected activity). In six patients (46%), 0.29% of injected activity accumulated in the regional lymph nodes and in three patients (23%), 0.62% of injected dose accumulated in the liver. Absorbed dose estimates were lung: 14 mGy, regional lymph nodes; 50 mGy, liver; 4 mGy. SPECT demonstrated good distribution of 153Sm-PHYP throughout the anterior knee compartments, although distribution to the posterior compartment was variable. CONCLUSION: Distribution is dependent on adequate knee flexion immediately following injection and may be influenced by the size range of labeled particles. Favorable biodistribution data suggest that 153Sm-PHYP is a potentially useful radiation synovectomy agent.