A survey of radiation synovectomy in Europe, 1991-1993

The future of radiosynoviorthesis: bright or bleak?

Radiosynoviorthesis (RSO) is a decades known, effective intra-articular nuclear medicine local therapy, with few rare side-effects, in which inflamed synovial membrane is treated by means of colloidal beta-emitters. There are major variations worldwide in terms of acceptance, frequency of use and approved indications for this procedure. Thus, reliable figures that reflect reality are only available for a few countries. A Europe-wide survey revealed that RSO is carried out most frequently in Germany, where RSO is the most common nuclear medicine therapy with about 70,000 joints treated per year. The main indications include synovitis due to rheumatoid arthritis, hemophilia and pigmented villonodular synovitis (PVNS), and depending on national approvals, osteoarthritis. Despite the many indications, there are very few published scientific studies and therefore, RSO evidence is lacking. Reliable data on the clinical usage of RSO and demographics of RSO specialists are only available in Germany, thus we discuss the future challenges of RSO mainly from a German perspective. In the German healthcare system, RSO is performed primarily on an outpatient basis and plays only a minor role in the university setting. The necessary expertise for RSO is therefore lacking, for the most part, at university training centers. Currently, nearly more than three quarters of the German RSO experts are over fifty years old, illustrating a shortage of young talent. In the future, RSO providers from the non-university or private sector will have to cooperate with universities through networks and will have to intensify their cooperation with referring physicians, such as rheumatologist and orthopedic surgeons, and patients in order to maintain a timely and beneficial exchange of information. In networks of RSO experts, the participants must jointly develop and establish training concepts and facilities for future talents, elaborate on guidelines, if clinically useful expand the range of indications, initiate studies to generate further evidence and finally make the procedure more public. In addition, it is worthwhile to apply this process beyond human medicine to other fields, such as medical physics and veterinary medicine. If these points are implemented, the future of RSO will be bright, if it fails, it looks bleak.

Intra-articular Treatment of Digital Osteoarthritis by Radiosynoviorthesis-Clinical Outcome in Long-term Follow-up

PURPOSE

This retrospective study analyzed the long-term effects of radiosynoviorthesis (RSO) with special emphasis to local joint pain in patients from 4 different RSO centers in Germany and Austria.

METHODS

A total of 168 finger joints in 147 patients with digital joint OA were investigated. The indication for RSO was based on both clinical complaints and a proven synovitis, despite anti-inflammatory pharmacotherapy and previous intra-articular corticosteroid injections. Radiosynoviorthesis was performed according to international guidelines. A numeric visual analog scale (VAS) before and after treatment was used to measure the outcome. Follow-up was done for at least 2 years after treatment, in some patients even over 10 years.

RESULTS

Radiosynoviorthesis resulted in a significant reduction of VAS values in most of the patients, lasting for the whole period of follow-up. Two-thirds of the treated joints showed clinically relevant improvement, if a reduction of 30% in VAS values was defined as a reasonable cutoff. The best results were achieved in thumb base joints.

CONCLUSIONS

This article confirms that RSO is a suitable treatment option for digital joint OA with a proven synovitis. The analgesic effect is long-lasting and comparable to the success of RSO in patients with rheumatoid arthritis.

H4octapa: synthesis, solution equilibria and complexes with useful radiopharmaceutical metal ions

H₄octapa is synthesized and complexed to nine metals of medicinal interest. Crystal structures of the ligand and its La complex were obtained. Solution equilibria for the ligand and several lanthanide complexes were investigated.

The use of 185 MBq and 740 MBq of 153-samarium hydroxyapatite for knee synovectomy in haemophilia

The penetration of beta energy of 153-samarium (¹⁵³Sm) (0.8 MeV) is not only appropriate for synovectomy of median articulations but is possible to improve the radiobiological effect using increased activities. The aim of this study was to assess the effectiveness of 185 MBq and 740 MBq of 153-samarium hydroxyapatite (¹⁵³Sm-HA) in knees of haemophilic patients. Thirty-one patients – 36 knees, 30 males, were divided into two groups without coinjection of corticosteroid: A – 14 patients (17 knees) treated with intra-articular dose of 185 MBq of ¹⁵³Sm-HA, average age 23 years; B – 17 patients (19 knees) with 740 MBq of ¹⁵³Sm-HA, average age 21.3 years. The evaluation before and after 1 year of synovectomy used the following criteria: reduction in the number of haemarthroses and use of the coagulation factor and improvement in articular motility. Adverse-effects occurrence was considered too. Early and late scintigraphic studies were performed after synoviorthesis and no joint immobilization was recommended. The reduction in haemarthrosis and use of coagulation factor were: group 1 – 31.3% and 25%; group 2 – 81.5% and 79% with P < 0.001 respectively; no significant improvement in knees motility was noted for both groups. Four cases of mild reactional synovitis were observed in each group. The scintigraphic control showed homogenous distribution of the radiopharmaceuticals with no articular escape; the material was considered safe by its permanence in the articulation. We have significant improvement in the synovectomy of haemophilic knees with 740 MBq of ¹⁵³Sm-HA; the less penetration of its beta radiation was compensated by the increased biological effect with the higher used activity.

Combined arthroscopic synovectomy and radiosynoviorthesis in the treatment of chronic non-specific synovitis of the knee

INTRODUCTION

Chronic non-specific synovitis has a higher recurrence rate with arthroscopic synovectomy due to the insufficient removal of all pathological tissues. Neither has radiosynoviorthesis been sufficiently effective in treatment in contrast to cases of chronic specific synovitis such as rheumatoid arthritis. This study aimed to investigate the efficiency of combined arthroscopic and radionuclide synovectomy in chronic non-specific synovitis of the knee with the evaluation of clinical and radiological results.

MATERIALS AND METHODS

14 knees of 14 patients (11 female, 3 male) diagnosed as chronic non-specific synovitis were treated with arthroscopic subtotal synovectomy combined with radiosynoviorthesis. The efficiency was evaluated retrospectively by comparing preoperative and postoperative modified cincinnati knee score, Visual Analogue Scale, joint USG and MRI. The mean age was 29.2 ± 10.3 years and the mean follow-up period was 30.3 ± 3.7 months.

RESULTS

Clinical parameters such as pain, limitation of motion and effusion were regressed. Daily activities at the final follow-up were significantly better than in the preoperative period. The mean modified cincinnati knee score of the patients increased from 25.8 ± 8.7 preoperatively to 67.8 ± 13.4 postoperatively (p = 0.002). The mean VAS score was 7.2 ± 1.1 preoperatively and 1.3 ± 0.8 postoperatively (p = 0.003). Clinically and radiologically on MRI there was no recurrence. Mean synovial membrane thickness was 4.5 ± 2.4 mm in the preoperative period. At the final follow-up, noticeable regression of synovial membrane thickness (2.1 ± 0.5 mm) was recorded in the knee joint USG (p = 0.015). No complications were observed.

CONCLUSION

The combination of arthroscopic subtotal synovectomy and radiosynoviorthesis can be an effective treatment modality for chronic non-specific synovitis of the knee.

90Y-labeled tin fluoride colloid as a promising therapeutic agent: preparation, characterization, and biological study in rats

In this study, tin fluoride colloid (SnF-c) was prepared, labeled with yttrium-90 ((90)Y), and characterized with respect to its physicochemical properties and biological behavior in an animal model. Particle size of SnF-c, at constant concentration of SnF(2), was dependent on pH, concentration of sodium fluoride (NaF), temperature, and time. The particle size of SnF-c decreased with an increase in NaF concentration and a decrease in reaction mixture pH. Radiolabeling yield of (90)Y-SnF-c at higher temperature increased and it was greater than 98% for the preparation at 95 °C. The (90)Y-SnF-c demonstrated high in vitro stability both in human serum and human synovial fluid at 37 °C up to 7 days. In vivo distribution studies in healthy male Wistar rats of (90)Y-SnF-c (particles <1 μm), following intravenous administration, revealed that the localization takes place preferably in the liver. The (90)Y-SnF-c (particles >1 μm) was well retained in the synovial space for 96 h after intra-articular injection, whereas leakage of (90)Y from the joint was 1.96% over this period. Because of high labeling yield and stability, (90)Y-SnF-c might be a promising agent for radiosynovectomy or therapy of liver malignancies.

¹⁵³Sm-HM for arthritic knee pain. Estimated dosimetry

Osteoarthritis is the most common type of arthropathy and after cardiovascular diseases is the most disabling disease in developing countries. The dosimetry for the clinical application of 153-samarium-hydroxymacroaggregates (¹⁵³Sm-HM) for radiation synovectomy (RSV) and palliative treatment for arthritic pain, as far as we know, has not been reported. The aim of this research was to estimate the radiation dose necessary for synovial ablation and pain palliation with minimum risk to the patient. ¹⁵³Sm-HM (370 MBq) was administered intra-articularly in a patient with severe knee pain and hindered motility. Regions of interest drawn on sequential, conjugated, anterior and posterior scintigraphy images were used to obtain the respective activity. The data was entered into a knee joint histological-geometric model designed with micrometric dimensions to represent the synovial cell layers. The Monte Carlo code was used to calculate the absorbed dose in each of the 12 model-cells representing the distance from the synovial liquid to the cartilage or bone. The absorbed dose in the synovial cavity was 114 Gy which is sufficient energy for RSV. The treated patient referred little pain and higher motility with no adverse reactions. ¹⁵³Sm-HM is a potentially valid radiopharmaceutical for RSV, which effectively palliates knee pain.

Complications following radiosynoviorthesis in osteoarthritis and arthroplasty: osteonecrosis and intra-articular infection

OBJECTIVES

In the literature, radiosynoviorthesis (RSO) has been associated only with a small number of complications. There is a trend towards increasing the use of RSO in diverse indications. After repeatedly observing several complications following RSO, a retrospective evaluation was undertaken to estimate the safety of this method.

METHODS

Between 1995-2007, we evaluated the outcome of RSO in 93 patients (143 knees, seven hips, seven shoulders, three elbows, one ankle) who presented to our orthopaedic department after joint treatment with yttrium-90((90)Y) or Rhenium-186((186)Re) colloid in an external nuclear medicine institution.

RESULTS

Seventy-nine of the 93 RSO treated patients had advanced primary or secondary osteoarthritis (OA), 12 had an arthroplasty. In seven cases, rheumatoid arthritis (RA) was responsible for secondary OA. The benefit in pain relief, as self-reported by the patients was low. Twenty-two of the 93 patients showed complications following RSO. We observed osteonecrosis (ON) in 19 and infection in five patients, including two with both complications. These findings were proven clinically, radiologically, intraoperatively, microbiologically and histologically. Statistical analysis revealed a strong correlation of arthroplasty to infection (rho=0.798, alpha=0.01), and a strong correlation of chronic obstructive pulmonary disease (COPD) and RA to ON following RSO (rho=0.674, alpha=0.01). Diabetes mellitus (DM) was also significantly correlated to ON after RSO treatment (rho=0.488,alpha=0.05).

CONCLUSIONS

Our data suggest that RSO may not be as safe as it has previously been reported, especially in advanced OA and arthroplasty.

Yttrium-90 radiation synovectomy in knee osteoarthritis: a prospective assessment at 6 and 12 months

OBJECTIVE

To assess the outcome of yttrium-90 radiation synovectomy at 6 and 12 months in patients with knee osteoarthritis unresponsive to systematic or local medical treatment.

METHODS

Consecutive patients with osteoarthritic knee pain resistant to conventional therapy and submitted to intraarticular yttrium-90 treatment because of synovial inflammation, as demonstrated by early-phase bone scintigraphy, were prospectively evaluated at 6 and/or 12 months. The assessment of the outcome of treatment was based on self-reporting of relief of knee pain limiting daily activities, measured as percentage reduction of the pretherapeutic joint discomfort with a Visual Analogue Scale. Resting and nocturnal pain also were considered, together with knee flexibility and ultrasonographic changes.

RESULTS

Among a total of 97 patients, a > or =50% Visual Analogue Scale pain palliation was experienced by 64 of 90 (71.1%) patients at 6 months and 50 of 69 (72.5%) at 12 months (P = 0.992). Moreover, nocturnal and resting pain alleviation, gain in knee flexibility and regression of large joint effusions and Baker's cysts were observed in considerable proportions. In the evaluation of the outcome of treatment in 62 patients with serial assessments using a composite criterion, 42 (67.7%) versus 40 (64.5%) had a satisfactory response at 6 and 12 months, respectively (P = 0.850). The probability of a favourable therapeutic result was inversely related to the severity of radiographic joint changes.

CONCLUSION

Yttrium-90 synovectomy exerts a beneficial therapeutic effect in a substantial proportion of patients with osteoarthritic knee pain and synovial inflammation, inadequately controlled by pharmacotherapy. Clinical improvement is inversely related to radiographic knee damage.

Effectiveness of radiation synovectomy with samarium-153 particulate hydroxyapatite in rheumatoid arthritis patients with knee synovitis: a controlled randomized double-blind trial

OBJECTIVES

The aim of the present study was to investigate the effectiveness of Samarium(153)-particulate hydroxyapatite radiation synovectomy in rheumatoid arthritis patients with chronic knee synovitis.

METHODS

Fifty-eight rheumatoid arthritis patients (60 knees) with chronic knee synovitis participated in a controlled double-blinded trial. Patients were randomized to receive either an intra-articular injection with 40 mg triamcinolone hexacetonide alone (TH group) or 40 mg triamcinolone hexacetonide combined with 15 mCi Samarium(153)-particulate hydroxyapatite (Sm/TH group). Blinded examination at baseline (T0) and at 1 (T1), 4 (T4), 12 (T12), 32 (T32), and 48 (T48) weeks post-intervention were performed on all patients and included a visual analog scale for joint pain and swelling as well as data on morning stiffness, flexion, extension, knee circumference, Likert scale of improvement, percentage of improvement, SF-36 generic quality of life questionnaire, Stanford Health Assessment Questionnaire (HAQ), Lequesne index, use of non-steroidal anti-inflammatory drugs or oral corticosteroids, events and adverse effects, calls to the physician, and hospital visits.

RESULTS

The sample was homogeneous at baseline, and there were no withdrawals. Improvement was observed in both groups in relation to T0, but no statistically significant differences between groups were observed regarding all variables at the time points studied. The Sm/TH group exhibited more adverse effects at T1 (p<0.05), but these were mild and transitory. No severe adverse effects were reported during follow-up.

CONCLUSION

Intra-articular injection of Samarium(153)-particulate hydroxyapatite (15 mCi) with 40 mg of triamcinolone hexacetonide is not superior to triamcinolone hexacetonide alone for the treatment of knee synovitis in patients with rheumatoid arthritis at 1 y of follow-up.

Radiosynoviorthesis (RSO): influencing factors and therapy monitoring

OBJECTIVE

To evaluate the effectiveness of radiosynoviorthesis (RSO) in relation to joint type and underlying disease by both self-assessment of patients and scintigraphic assessment to determine conditions under which RSO might be preferable to the sole intra-articular corticoid injection.

METHODS

Radiosynoviorthesis was performed on 136 patients for 424 joints [242 small, 130 medium-sized, and 52 large joints; 313 with rheumatoid arthritis (RA) and 111 with osteoarthritis (OA)]. The success of RSO was evaluated after 12 months by patients' estimation, and in 35 patients for 157 joints additionally by two-phase bone scintigraphy. The relative change in the scintigraphic uptake was compared with the patients' estimation.

RESULTS

The subjectively estimated success rates for the small, medium-sized, and large joints were 89% (215/242), 86% (112/130), and 79% (41/52), and for RA and OA 89% (280/313) and 79% (88/111), respectively. The scintigraphically determined response rates for small and medium-sized joints were 81% (86/106) and 69% (35/51), respectively. There was a mismatch between patients' assessment and scintigraphic assessments in 18% (28/157) with 6 false-negative and 22 false-positive estimations using scintigraphy as the standard of reference.

CONCLUSIONS

The success of RSO is higher in patients with RA than in patients with OA. For the finger, ankle, and wrist joints in RA, RSO is so promising that we would like to advocate its preference over the sole intraarticular corticoid injection. Perfusion bone scintigraphy can be used for therapy monitoring and earlier switching to RSO by showing that other therapies have failed.

Radiation synovectomy with 90Y colloid in the therapy of recurrent knee joint effusions in patients with inflammatory joint diseases

The aim of this study was to assess the effectiveness of radiation synovectomy (RSV) in the treatment of recurrent joint effusions, using 90Y in patients with chosen inflammatory joint diseases. The group of treated patients consisted of 30 people. Qualification for the treatment was based on clinical assessment, three-phase bone scintigraphy (BS3) and biochemical analysis. Intra-articular injection of 90Y was performed. Biochemical analysis was repeated after 48 h, 4 and 24 weeks, whereas BS3 was repeated after 24 weeks. Changes in the second phase of BS3 were assessed visually, using a four-degree scale and in the third phase, semiquantitatively with J/B ratio. The changes in the blood pool phase before RSV were 3.4 +/- 0.6 and after the therapy 2.00 +/- 0.8 (P < 0.001). The J/B ratio was: before RSV 2.58 +/- 08; after treatment 2.09 +/- 0.9 (P < 0.05). RSV is an effective method to treat recurrent effusions in patients with RA and SPA.

The intra-articular distribution of 90yttrium does not influence the clinical outcome of radiation synovectomy of the knee

OBJECTIVES

To assess the impact of the intra-articular distribution of (90)yttrium-citrate ((90)Y) on the clinical effect of radiosynoviorthesis (RSO) of the knee and on (90)Y leakage from this joint.

METHODS

Patients with arthritis of the knee received 185 MBq (90)Y combined with a glucocorticoid, followed by clinical bed rest. Intra-articular (90)Y distribution, measured with a dual-head gamma camera immediately or after 24 hours, was scored as mainly diffuse or mainly focal. Leakage to regional lymph nodes, the liver and spleen was assessed with a dual-head gamma camera after 24 hours. Clinical effect was scored after 6 months by a composite change index (CCI), range 0-12; responders were defined as having a CCI > or =6.

RESULTS

Seventy-eight knees of 69 patients, mostly suffering from undifferentiated arthritis (42%) or RA (28%), were treated. (90)Y distribution was mainly diffuse in 54% and mainly focal in 46% with clinical response rates of 40% versus 56%, respectively, p = 0.3. CCI was not correlated with distribution. (90)Y leakage was found only to the liver and the spleen (mean leakage 0.4% and 1.1%, respectively). Leakage was significantly less in case of diffuse intra-articular (90)Y distribution, whereas leakage to the liver was correlated with distribution (r = 0.68, p<0.001). (90)Y leakage was not correlated with CCI.

CONCLUSIONS

Intra-articular (90)Y distribution does not influence the clinical effect of RSO of the knee. Although (90)Y leakage from the joint is less if (90)Y distributes diffusely in the joint cavity, leakage does not seem to hamper the clinical effect.

Applied radioactivity in radiation synovectomy with [188Re]rhenium sulfide suspension

BACKGROUND

Early experience demonstrated absorbed dose in radiation synovectomy is about 100 Gy. For reaching this dose, the applied radioactivity should be calculated.

METHOD

Twenty-nine synovitic models of rabbit were treated by intra-articular injection of [(188)Re]rhenium sulfide and histological changes of synovium and cartilage were examined. The applied radioactivity was calculated by method of absorbed dose factor. In clinical, eleven haemophilic patients with haemarthrosis were performed radiation synovectomy with treated [(188)Re]rhenium sulfide. The synovial thickness was evaluated by MR and its value was used to calculate the applied radioactivity. After radiation synovectomy, all patients were followed up by synovial thickness, regional inflammation, and clinical course including bleeding frequency.

RESULTS

In rabbit models, the synovitic membrane can be eliminated by calculated radioactivity as planed without damaging the joint cartilage. In patients study, all patients exhibited significant reductions in synovial thickness and inflammation after radiation synovectomy with the planed radioactivities of [(188)Re]rhenium sulfide. Post-procedure bleeding frequency reduction in excellent and good reached to 63.6% by 18 months. In the cases of joint bleeding, the need for antihaemophilic factor treatment decreased immensely. Most of the recurrent episodes of bleeding were mild, subsiding with local means.

CONCLUSION

The applied radioactivity in radiation synovectomy could be calculated according to thickness of inflamed synovium. Further study including comparison therapeutic results from calculated individual activities with results from fixed activities and long-term follow-up is warranted.

Radiosynoviorthese

Intraarticular therapy is an established form of therapy in chronic inflammatory joint diseases. Besides the injection of glucocorticoids, radiosynoviorthesis is a frequently used procedure. Intraarticular injected beta-emitting radionuclides are indicated in chronic synovitis with recurrent joint effusions in rheumatoid arthritis, seronegative spondyloarthritis, villonodular synovitis after surgery and for bleeding prophylaxis in haemophilic arthropathy. The value of radiosynoviorthesis in activated osteoarthritis is not yet clarified.

Radiation synovectomy with yttrium-90 for persisting arthritis has direct harmful effects on human cartilage that cannot be prevented by co-administration of glucocorticoids: an in vitro study

BACKGROUND

It was recently shown that radiation synovectomy with yttrium-90 (90Y) and glucocorticoids is not superior to intra-articular glucocorticoids alone in the treatment of persistent gonarthritis. In that study, it seemed that in patients treated by radiation synovectomy, progression of radiographic joint damage occurred.

OBJECTIVE

To test in vitro the direct effects of radiation synovectomy with 90Y on human cartilage.

METHODS

Human cartilage tissue was exposed to 90Y, glucocorticoids or the combination. 1:2000 to 1:20 dilutions of the clinical dose of 5 mCi/ml 90Y and 20 mg/ml glucocorticoids were used. After a 4-day exposure and a subsequent 12-day recovery period, proteoglycan synthesis, proteoglycan release and proteoglycan content were measured. In addition, human synovial tissue was cultured for 4 days with 90Y or glucocorticoids. Culture supernatants were analysed for cartilage-destructive activity.

RESULTS

90Y, glucocorticoids and the combination inhibited proteoglycan synthesis considerably and dose dependently, an effect that sustained for at least 12 days. Proteoglycan release was transiently increased by 90Y, an effect that was not changed by addition of glucocorticoids, which had no effect on its own. Proteoglycan content was eventually adversely affected by 90Y, an effect hardly influenced by glucocorticoids. Neither 90Y nor glucocorticoids changed the cartilage-destructive properties of synovial tissue.

CONCLUSIONS

90Y, but not glucocorticoids, has direct harmful effects on cartilage in vitro. Indirect beneficial effects of 90Y via inhibition of cartilage-destructive properties of synovial tissue could not be shown. These observations may explain the possible radiographic joint damage on radiation synovectomy.

Radiosynoviorthesis in Osteoarthritis and Other Disorders with Concomitant Synovitis in Comparison to Rheumatoid Arthritis

AIM

The aim of this study was to evaluate the effectiveness of radiosynoviorthesis (RSO) in osteoarthritis and other disorders with concomitant synovitis versus rheumatoid arthritis by means of a standardized questionnaire.

METHODS

Eight-hundred and three RSO treatments were monitored in 691 patients by seven centers in three countries, using standardized questionnaires. Patients were assigned to three groups according to their age (20-40, 41-60, and 61-80 years). Additionally, the data was analyzed separately for patients with rheumatoid arthritis (group A) and those with osteoarthritis, psoriasis arthritis, pigmental villonodular synovitis, or persistent effusions after joint replacement (group B).

RESULTS

Quality of life improved in 78% of group A and 59% of group B (p < 0.01). Ameliorations of joint pain, swelling/effusion, or flexibility were found in 80% of group A and 56% of group B (p < 0.01). The response rate was similar for small- and large-sized joints in group A, but was significantly higher for large-sized joints in group B (p < 0.01). The positive effects on joint pain, swelling/effusion, or flexibility lasted longer in group A (p < 0.01). Repeated RSOs were as effective as initial RSOs. The clinical outcome was not influenced by age, gender, or transient immobilization for 48 hours after RSO.

CONCLUSION

Although slightly more efficient in rheumatoid arthritis, RSO represents an effective treatment option also in osteoarthritis and other disorders with concomitant synovitis.

Effects of Radiosynovectomy with P-32 Colloid Therapy in Hemophilia and Rheumatoid Arthritis

AIM

The aim of this study was to assess the effects of treatment with our locally produced P-32 colloidal suspension on knee synovitic inflammations of hemophilic and rheumatoid arthritis (RA) patients, as well as to compare results with chemical synovectomy or corticoid intra-articular injections and evaluate the cost-benefit ratio.

MATERIALS AND METHODS

Thirty-six hemophilic male patients, 4-28 years of age and sent by the Hemophilic Foundation (Buenos Aires, Argentina), were enrolled for knee radiosynovectomy (RS) with P-32 colloid (26 patients), or the antibiotic rifampicin with the cooperation of orthopaedists (10 patients). Parents' informed consent was obtained. The following procedures were performed: routine blood tests, X-ray, ultrasound, a 3-phase bone scan, plus monthly methylene diphosphonate (MDP) controls. Patients were included in this study only if several knee episodes had occurred. Exclusion criteria included bone destruction and big Baker's cyst. Twelve RA patients were included, with similar selection criteria: 6 RA patients received P-32 therapy, and the other 6 patients intra-articular corticoids. Clinical, blind evaluation (state of joint involvement, pain, motility, requirements of antihemophilic factors, corticoids, or analgesics) was registered in follow-up charts. If required, joint aspiration was carried out. Intra-articular instillation of saline plus flushing was done before the needle was withdrawn. P- 32 Bremsstrahlung emission was used in the gamma camera for early and late imaging to confirm the absence of leakage. For intra-articular chemical injections therapy, 4 MBq of Tc-99m MAA (macroaggregates) was used. Immobilization and relative rest for 72 hours followed the procedures.

RESULTS

There were neither local or systemic effects, nor leakage during P-32 treatment. Intra-articular rifampicin and corticoids procedures required frequent injections. Comparison of regions of interest (ROIs) in treated knees during soft-tissue scintigraphies in pre- and post-third MDP control showed knee improvement. The follow-up evaluation demonstrated an increase in joint motion, diminished volume, and less requirement and frequency of the use of antihemophilic factors (AHF) in 80% of the radiosynovectomies (21 of 26), thus lowering health costs. Five female RA patients (5 of 6) had decreased joint swelling and pains, resulting in increased joint motion.

CONCLUSIONS

Radiosynovectomy in RA showed a 3-month pain palliative effect. One intra-articular knee radiosynoviorthesis in haemophilic patients provides a more than 3- month relief of symptoms after treatment with locally produced P-32 (11 patients). This turned out to be a safe, economic alternative procedure in emerging nations where the availability of AHF is difficult and expensive.

Clinical efficacy of radiation synovectomy in digital joint osteoarthritis

PURPOSE

Radiation synovectomy was developed for local treatment of rheumatoid arthritis. In this study, the long-term efficacy of radiation synovectomy was retrospectively evaluated in patients with osteoarthritis (activated arthrosis) of the digital joints using an algofunctional score.

METHODS

Fifty-three digital joints in 29 patients (mean age 64.8 years) were treated by intra-articular injection of 169Er citrate. All joints were painful despite pharmacotherapy and showed an elevated blood pool pattern in a pretherapeutic three-phase bone scan, indicative for local synovitis. The patients were asked to classify their complaints with respect to different daily manual activities on a ten-step pain scale from 1 (total disability) to 10 (lack of any impairment) prior to and after treatment, with a mean follow-up of 41 months. Local signs of osteoarthritis such as joint swelling or pain were additionally evaluated and were scored from progression of complaints to excellent improvement based on patient self-evaluation.

RESULTS

All patients reported a pronounced improvement in their manual activities. The mean total score of 4.73+/-0.58 for all activities prior to treatment increased significantly to 6.79+/-0.47 after radiation synovectomy (p<0.05). The best results were obtained in the thumb base joints, whereas distal interphalangeal joints were frequently resistant to therapy.

CONCLUSION

Radiation synovectomy is highly effective in digital joint osteoarthritis with concomitant local synovitis.

Is corticosteroid coinjection necessary for radiosynoviorthesis of patients with hemophilia?

PURPOSE

Radiation synovectomy is frequently combined with intraarticular corticosteroid injection in the treatment of rheumatoid arthritis to reduce local inflammation and lymphatic clearance of radiocolloid. However, this practice is not universally accepted because corticosteroids have local and systemic toxicity such as osteonecrosis and cartilage damage and whether simultaneous corticosteroid injection together with radiocolloids is necessary in other forms of chronic synovitis like patients with hemophilia remains to be determined.

MATERIALS AND METHODS

In this study, we performed radiosynoviorthesis in 14 joints of 12 patients with hemophilia with chronic knee synovitis without corticosteroid coadministration and measured radiocolloid leakage from the joint space. Five mCi Y-90 radiocolloid was injected under local anesthesia and the needle was flushed with additional lidocaine injection instead of corticosteroid. The joint was then manipulated through a full range of extension and flexion to distribute the particles homogeneously throughout the joint space. The joint was then splinted for 48 hours to minimize leakage from the joint space. After the immobilization period, radiocolloid leakage was evaluated using a gamma camera with a 20% window centered over the maximum Bremsstrahlung photopeak of Y-90. Regions of interest were drawn to the injection site on the knee joint and to the ipsilateral inguinal lymph node area. Leakage of radiocolloid was calculated by dividing the background-corrected counts/pixel at the inguinal region by the counts/pixel at the injection site.

RESULTS

One of 12 patients who had knee arthroplasty was previously found to have a high amount of leakage. In this patient, 70% of radiocolloid at the injection site drained into the pelvic lymph nodes. In the remaining 11 patients, no lymph nodes were visualized in the groin area and the measured average leakage for these patients was 2.3% (range, 0-13).

CONCLUSION

We concluded that in cases of appropriate particle size and strict immobilization of knee joints, leakage of radiocolloid was minimal and steroid coinjection might not be necessary for radiosynoviorthesis of patients with hemophilia with chronic knee synovitis.

Radiation synovectomy by 188Re-Sulfide in haemophilic synovitis

Radiation synovectomy is a safe and effective treatment for chronic haemophilic synovitis causing recurrent haemarthroses. This study reports results of 29 188Re-sulfide radiation synovectomies in knee joint with a follow-up 18 months. Using the absorbed dose factor, three groups of radioactivity dose (555 MBq, 687 MBq and 917 MBq) were used according to the synovium thickness that measured by MRI. Excellent and good results (haemarthrosis reduction from 75 to 100%) were obtained in 71% of cases at 18 months. Comparison of the results, no significant difference was found among the radioactivity dose groups. Radiation was well contained within the knee. There were no observed or identified complications including the detectable harm to the articular cartilage, as shown by MRI.

188Re radiopharmaceuticals for radiosynovectomy: evaluation and comparison of tin colloid, hydroxyapatite and tin-ferric hydroxide macroaggregates

Background

Radiosynovectomy is a therapy used to relieve pain and inflammation from rheumatoid arthritis and related diseases. In this study three ¹⁸⁸Re particulate compounds were characterized according to their physico-chemical properties and their biological behavior in rabbits. The results were compared in order to establish which was the radiopharmaceutical that better fits the requirements of this kind of radiotherapy.

Methods

Three radiopharmaceutical formulations, tin colloid, hydroxyapatite particles (HA) and ferric hydroxide macroaggregates coated with tin colloid (FHMA), were physically characterized (number, volume and surface of the particles). For this purpose laser diffraction methodology was used. To evaluate cavity leakage of activity the following studies in New Zealand rabbits were performed: scintigraphic images for 48 hr after intraarticular injection of each radiopharmaceutical, biodistribution at 48 hr and urine samples collection during the first 24 hr post-radiopharmaceutical administration.

Results

Labeling procedures for ¹⁸⁸Re-HA and ¹⁸⁸Re-Sn-FHMA were labour intensive while ¹⁸⁸Re-Sn was easily prepared. Furthermore, ¹⁸⁸Re-Sn colloid offered the greatest surface area in the 2–10 microm range and was obtained with a radiochemical purity over 95%, while percentage of bound activity for ¹⁸⁸Re-HA and ¹⁸⁸Re-Sn-FHMA were 55% and 92% respectively. Stability was verified for the three radiopharmaceuticals for 24 hr. Scintigraphic studies and biodistribution in rabbits after intraarticular administration of the radiopharmaceuticals showed relevant activity only in the knee, this being over 90% of the residual activity in the whole body at 48 hr in every case. Renal elimination of ¹⁸⁸Re-Sn colloid and ¹⁸⁸Re-Sn-FHMA was detected by activity measurements in urine samples, during the first 12 hr post-radiopharmaceutical injection.

The percentage of activity retained in the knee was 69.1% for ¹⁸⁸Re-Sn colloid, 55.1% for ¹⁸⁸Re-Sn-FHMA and 33.6% for ¹⁸⁸Re-HA.

Conclusion

The ¹⁸⁸Re-Sn colloid was easy to prepare, minimum facilities were required, was stable for 24 hr and showed minimal leakage from the joint after intraarticular injection into the rabbit's knee. Furthermore, ¹⁸⁸Re-Sn colloid has greater retention in the knee when it is compared with the other radiopharmaceuticals, so it could provide the best therapeutic effect/absorbed dose ratio for the patient.

Preparation of 153Sm-chitosan complex for radiation synovectomy

A samarium 153-chitosan complex was prepared by simply mixing acidic solutions of chitosan and (153)SmCl(3). When a solution of this complex was injected into the knee joints of rabbits, minimal extra-articular leakage was observed. This can be attributed to the rapid change in the pH of the complex solution from acidic to neutral, resulting in the formation of gel followed by the subsequent retention in the administered site. Thus, the complex solution represents a promising candidate for radiation synovectomy.

Long-term results of radiation synovectomy: a clinical follow-up study

Radiation synovectomy by intra-articular injection of beta-emitting radionuclides is a reliable and easy-to-perform therapy without harmful side effects for the treatment of inflammatory rheumatoid as well as degenerative joint diseases. The indication for radiation synovectomy is based on both clinical symptoms and on proven hyperperfusion, with active synovitis being seen on a pre-therapeutic three-phase bone scan. In this study, the clinical response after 6-18 months, evaluated by a standardized questionnaire, was compared with the reduction of synovitis seen on three-phase bone scintigraphy after treatment of 475 joints in 151 patients. The best clinical results were obtained in cases of true rheumatoid arthritis (73.4%), with less in other kinds of arthritis (48.8%) such as psoriatic or reactive arthritis. Because of the inflamed synovium being the main target tissue, clinical results in osteoarthritis with severe bone destruction are poorer (33.9%). However, synovitis can be markedly reduced (in approximately 70%), regardless of the underlying diagnosis, as shown by post-therapeutic three-phase bone scanning. Radiation synovectomy can be recommended in all kinds of arthritis. It should also be considered in cases of osteoarthritis as a last therapeutic option prior to joint replacement.

Development of an in vitro model for assessing the in vivo stability of lanthanide chelates

An in vitro model was developed to evaluate the in vivo stability of lanthanide polyaminocarboxylate complexes. The ligand-to-metal ratios for the chelates EDTA, CDTA, DTPA, MA-DTPA (monoamide-DTPA) and DOTA with the lanthanides lanthanum, samarium, and lutetium were optimized to achieve > or = 98% complexation yield for the resultant radiolanthanide complexes. The exchange of the radiolanthanides from their EDTA, CDTA, DTPA, MA-DTPA and DOTA complexes with Ca(2+) was determined by in vitro adsorption and in vitro column studies using hydroxyapatite (HA), an in vitro bone model. In vitro serum stability of these radiolanthanide complexes was used as an additional indicator of in vivo stability, although the mechanism of instability in serum will be different than with bone. The in vitro studies were consistent with the expected findings that the smallest lanthanide (Lu) formed the most stable complexes. In vivo studies were done to validate the in vitro model. Biodistribution studies in normal CF-1 mice showed that in vivo stability of the complex (i.e., the more lanthanide remaining in complex form) could be assessed by a combination of the urinary, bone and liver uptake. For example, biodistribution studies demonstrate that high urinary excretion correlated with complex stability, while high liver plus bone uptake correlated with complex instability. The urinary excretion of the EDTA complexes decreased from (177)Lu to (140)La indicating a loss in stability in the direction of (140)La, consistent with the in vitro studies. The more stable a lanthanide complex is, the lower its exchange with HA in vitro will be, and the lower its combined bone plus liver uptake and higher its urinary excretion will be in vivo. This investigation indicates that the in vivo stability can be determined by a screening method that measures the degree of exchange from the lanthanide chelate with hydroxyapatite (HA) and its serum stability.

Yttrium radiosynoviorthesis in the treatment of knee arthritis in rheumatoid arthritis: a systematic review

OBJECTIVE

To consider the question: How strong is the evidence in favour of yttrium synovectomy in chronic knee arthritis in patients with rheumatoid arthritis in comparison with placebo and intra-articular steroid treatment?

METHODS

A systematic review of the literature was performed using Medline and the Embase database.

RESULTS

Initially, seven papers were identified, but only two met the inclusion criteria. Neither study showed evidence in favour of yttrium synovectomy.

CONCLUSION

From the point of view of evidence based medicine it should be seriously questioned whether yttrium synovectomy deserves a place in clinical practice.

Management of therapy-resistant rheumatoid arthritis

During the last two decades, newly introduced therapeutic strategies have resulted in satisfactory modification of the disease course in the majority of the patients with rheumatoid arthritis (RA). Nevertheless, a definite number of RA patients remain therapy-resistant, and for this group more aggressive treatment may be required for preventing permanent disability and progressive joint damage necessitating surgical procedures. Therefore, management of therapy-resistant RA is one of the major challenges in modern rheumatology. RA patients who have not responded to conventional disease-modifying antirheumatic drug (DMARD) therapy are defined as refractory RA patients. However, a uniform description or definition for 'refractory' RA does not appear to be available. In this article we will deal with, and discuss, the term 'refractory RA' based on a MEDLINE database search using this term, currently available therapeutic options, data on therapy-resistant RA patients from an inception cohort of RA patients attending the Nijmegen University Hospital, management of extra-articular manifestations and future management strategies.

Radiochemical synovectomy

Radiochemical synovectomies have been used for nearly fifty years for the treatment of persistent monoarticular synovitis refractory to antiinflammatory drugs, disease modifying drugs, and intraarticular corticosteroids. It is a therapeutic alternative to surgical synovectomy. There are controversies concerning safety, choice of appropriate agent, and logistics of administration. These concerns are discussed in addition to reviewing some of the more recent trials examining the efficacy of radiochemical synovectomy. It is clear that in properly selected patients this procedure is safe and beneficial.

Clinical outcome after one year following samarium-153 particulate hydroxyapatite radiation synovectomy

The clinical outcome and tolerability following treatment with samarium-153 particulate hydroxyapatite was evaluated in patients with persistent rheumatoid knee synovitis. The clinical review of 18 patients treated with intra-articular samarium-153 particulate hydroxyapatite combined with triamcinolone hexacetonide who had failed to obtain more than 4 weeks symptom relief from a prior intra-articular glucocorticoid injection was undertaken. No unwanted effects from the treatment were observed. Symptom relief was maintained in 56% patients at 6 months and in 44% of patients at 12 months following treatment. Median duration of symptom relief was 9 months. There was a significantly higher mean baseline Ritchie Articular Index in patients relapsing within 3 months and a trend towards earlier relapse in patients with higher indices of disease activity at the time of treatment. There was a trend towards earlier relapse in patients with a poor range of knee flexion at baseline and with worse indices of intra-articular radiopharmaceutical distribution. Samarium-153 particulate hydroxyapatite knee synovectomy is well tolerated and may be an effective treatment for carefully selected patients with persistent rheumatoid knee synovitis.