Treatment of rheumatoid synovitis of the knee with intraarticular injection of dysprosium 165‐ferric hydroxide macroaggregates

Abstract

One hundred eight knees of 93 patients with seropositive rheumatoid arthritis and persistent synovitis of the knee were treated with an intraarticular injection of 270 mCi of dysprosium 165 bound to ferric hydroxide macroaggregate. Leakage of radioactivity from the injected joint was minimal. Mean leakage to the venous blood 3 hours after injection was 0.11% of the injected dose; this corresponds to a mean whole body dose of 0.2 rads. Mean leakage to the liver 24 hours after injection was 0.64% of the injected dose; this corresponds to a mean liver dose of 3.2 rads. In 7 additional patients examined, there was negligible or near negligible activity found in the draining inguinal lymph nodes. One-year followup was possible for 74 knees (63 patients). Sixty-one percent of the knees had good results, 23% had fair results, and 16% had poor results.There was a direct correlation between the radiographic Submitted for publication January 14, 1985; accepted in revised form June 24, 1985. stage and response to treatment. In knees with stage I radiographic changes, 72% showed good results; 93% showed improvement. In knees with stage I1 changes, 59% showed good results; 81% showed improvement. These preliminary results indicate that dysprosium 165-ferric hydroxide macroaggregate is an effective agent for radiation synovectomy. The low leakage rates observed offer a definite advantage over agents previously used.

Suppression of glycosaminoglycan synthesis by articular cartilage, but not of hyaluronic acid synthesis by synovium, after exposure to radiation

“…Pavelka et a1 (5) found only foci of mild degeneration in the tangential layer of normal rabbit knee cartilage after intraarticular injection of 0.2-0.4 mCi of 90Y. Using the P-dosimetry formula (1 1) and an estimated lapine synovial mass of 300 mg (Myers S: unpublished observations), it can be calculated that the dose received by the joint in those studies ranged from 122,500 rads to 245,000 rads.…”

“…Since cells that are most susceptible to the effects of radiation are generally those that exhibit a rapid rate of cell division (2), and chondrocytes in normal adult articular cartilage lack mitotic activity (3), radiation might be expected to have little effect on this tissue. In support of this, only minimal histologic alteration has been seen in cartilage following irradiation (2,(4)(5)(6), even with as much as 640,000 rads (6).…”

“…Since cells that are most susceptible to the effects of radiation are generally those that exhibit a rapid rate of cell division (2), and chondrocytes in normal adult articular cartilage lack mitotic activity (3), radiation might be expected to have little effect on this tissue. In support of this, only minimal histologic alteration has been seen in cartilage following irradiation (2,(4)(5)(6), even with as much as 640,000 rads (6).We recently examined the effects of injection of yttrium 90 (90Y) into normal canine knees (7). While synovium from the irradiated knees exhibited extensive subintimal fibrosis and fibrin deposition, the histologic appearance of articular cartilage from these knees remained normal, suggesting that radiosynovectomy had not damaged the cartilage.…”

Einsatz der Radiosynoviorthese bei entzündlich-rheumatischen Gelenkerkrankungen

“…ten in Frühstadien entzündlich-rheumatischer Gelenkerkrankungen, bei denen die knöchernen Veränderungen noch nicht weit fortgeschritten sind (14)(15)(16)18).…”

Treatment of antigen‐induced arthritis in rabbits with dysprosium‐165–ferric hydroxide macroaggregates

“…FHMA particles are 1-5 pm in diameter and form a stable complex with 165Dy (15). 165Dy-FHMA has been shown to be an effective agent of radiation synovectomy in both laboratory and pre-liminary clinical studies (14,15,16,18). Previous laboratory studies using the antigen-induced arthritis (AIA) model have only assessed the histological changes 1 day and 4 weeks after radiation synovectomy (15).…”