Laser treatment of synovial inflammatory process in experimentally induced microcrystalline arthritis in Wistar rats

The presence of intra-articular crystals is detected in different articular pathologies of acute or chronic nature. The aim of this work was to analyze the action of the indium gallium aluminum and phosphorus (InGaAlP) (λ = 670 nm) laser on the synovial membrane present in the knee joint in experimentally induced microcrystalline arthritis in male adult Wistar rats. The animals were divided into three experimental groups (n = 24): control (A), experimentally induced arthritis (B), experimentally induced arthritis+InGaAlP laser therapy (C). The laser treatment was made daily in the patellar region of the right knee after 48 h of the experimental induction. After 7, 14, and 21 days of therapy, the rats were euthanized and the right knees were removed and processed for histomorphometric, immunohistochemical, ultrastructural, and biochemical investigation of the synovium. The number of granulocytes on the 14th and 21st days was higher in B and lower in C and, lastly, in A. The number of fibroblasts on the 14th and 21st days was similar between A and C and below B. The number of blood vessels on the 21st day was higher in B than in the other groups. The positive number of cells for the TUNEL test was higher on the 14th and 21st days in B compared to the others. The percentage of tissue area occupied by birefringent collagen fibers was higher in B on the 21st day than in the others. The ultrastructure of cells showed fibroblast-like morphology in all groups and periods evaluated. The quantification of glycosaminoglycans did not present significant differences between the groups in all the experimental periods. The amount of hydroxyproline was higher in B compared to the other groups on the 14th and 21st days. The content of non-collagen proteins was higher in B on the 21st day in relation to the other groups. Quantification of TNF-α on the 21st day was higher in A and B than in C. For TGF-β on the 21st day, groups B and C presented similar and higher values than A. For MMP-13, groups A and B presented data similar to and above C. In relation to ADAMT-S4, on the 21st day, groups B and C presented data similar to and lower than A. InGaAlP-670 nm therapy reduced the inflammatory process and tissue injuries of the synovial membrane in comparison to the untreated group, indicating its potential utilization in clinical studies aiming in the recovery of acute arthritis in patients.

Boron neutron capture synovectomy (BNCS) as a potential therapy for rheumatoid arthritis: radiobiological studies at RA-1 Nuclear Reactor in a model of antigen-induced arthritis in rabbits

Rheumatoid arthritis is a chronic autoimmune pathology characterized by the proliferation and inflammation of the synovium. Boron neutron capture synovectomy (BNCS), a binary treatment modality that combines the preferential incorporation of boron carriers to target tissue and neutron irradiation, was proposed to treat the pathological synovium in arthritis. In a previous biodistribution study, we showed the incorporation of therapeutically useful boron concentrations to the pathological synovium in a model of antigen-induced arthritis (AIA) in rabbits, employing two boron compounds approved for their use in humans, i.e., decahydrodecaborate (GB-10) and boronophenylalanine (BPA). The aim of the present study was to perform low-dose BNCS studies at the RA-1 Nuclear Reactor in the same model. Neutron irradiation was performed post intra-articular administration of BPA or GB-10 to deliver 2.4 or 3.9 Gy, respectively, to synovium (BNCS-AIA). AIA and healthy animals (no AIA) were used as controls. The animals were followed clinically for 2 months. At that time, biochemical, magnetic resonance imaging (MRI) and histological studies were performed. BNCS-AIA animals did not show any toxic effects, swelling or pain on palpation. In BNCS-AIA, the post-treatment levels of TNF-α decreased in four of six rabbits and IFN-γ levels decreased in five of six rabbits. In all cases, MRI images of the knee joint in BNCS-AIA resembled those of no AIA, with no necrosis or periarticular effusion. Synovial membranes of BNCS-AIA were histologically similar to no AIA. BPA-BNCS and GB-10-BNCS, even at low doses, would be therapeutically useful for the local treatment of rheumatoid arthritis.

The effects of low-dose radiotherapy on fresh osteochondral allografts: An experimental study in rabbits

Objective

The aim of this study was to investigate the effects of low-dose fractionated radiotherapy on cartilage degeneration after distal femoral fresh massive osteochondral allograft transplantation.

Methods

Twenty-four New Zealand White rabbits were divided into three groups of 8 rabbits each. All rabbits underwent distal femoral medial condyle fresh massive osteochondral allograft transplantation from California rabbits. The group 1 underwent transplantation without any preliminary process. The group 2 underwent fractionated local radiotherapy of 100 cGy for five days starting on the transplantation day. The group 3 included the rabbits to which the grafts transplanted after radiating in vitro by a single dose radiation of 1500 cGy. The hosts were sacrificed twelve weeks later. Anteroposterior and lateral radiographs were taken. Synovial tissue, cartilaginous tissue, and subchondral bone were assessed histopathologically.

Results

Nonunion was present in three cases of group 2 and one of group 3 in which cartilage degeneration was more severe. Synovial hypertrophy and pannus formation were more obvious in non-radiated rabbits. Hypocellularity and necrosis of the subchondral bone were rare in group 2. More cartilage tissue impairment was present in group 3 compared to group 1.

Conclusion

In osteochondral massive allograft transplantations, the immune reaction of the host could be precluded with radiotherapy, and the side-effects can be prevented by low-dose fractionated regimen. The total dose of fractionated radiotherapy for an immune suppression should be adjusted not to damage the cartilage tissue, but to avoid articular degeneration in the long term.

Comparative study of membranes induced by PMMA or silicone in rats, and influence of external radiotherapy

The induced membrane technique has been used for long bone defect reconstruction after traumatism. One of the major drawbacks of this method is the difficult removal of the polymethyl methacrylate spacer after membrane formation. We therefore replaced the stiff PMMA spacer with a semi-flexible medical grade silicone spacer. This study aimed to compare subcutaneously formed membranes, induced by PMMA and silicone, in the irradiated or not irradiated areas within 28 rats that received the spacers. Histological analysis was performed to evaluate the composition of the membrane and to quantify the amount of vessels. Histomorphometric measurements were used to evaluate membranes' thickness, while fibrosis and inflammation were scored. The expression of VEGF and BMP-2 in lysates of the crushed membranes was determined by Western blotting. ALP expression was analyzed in HBMSC cultures in contact with the same lysates. Non-irradiated membranes induced by the two spacer types were non-inflammatory, fibrous and organized in layers. Irradiation did not change the macroscopic properties of membranes that were induced by silicone, while PMMA induced membranes were sensitive to the radiotherapy, resulting in thicker, strongly inflammatory membranes. Irradiated membranes showed an overall reduced osteogenic potential. Medical grade silicone is safe for the use in radiotherapy and might therefore be of great advantage for patients in need of cancer treatment.

[Recurrent intra-articular bleeding episodes in haemophiliacs. Treatment outcomes in the patients at the university hospital motol in 1985-2005]

PURPOSE OF THE STUDY

Chronic synovitis is a common finding in people with haemophilia. It regularly appears after recurrent episodes of intra-articular bleeding. The bleeding originates from the subsynovial venous plexus underlying the capsule where a lack of thromboplastic activity has been demonstrated. Therefore, the changed synovium appears to be a treatment target. There are several methods which can be used to remove the synovial layer from the joint. The aim of our study was to asses the efficacy of different treatment approaches used in a group of haemophiliacs between 1985 and 2005 in our hospital.

MATERIAL AND METHODS

A group of 30 patients with bleeding disorders was evaluated in the study. There were 29 men with haemophilia and one woman with von Wilebrandt factor deficiency. Their age ranged from 6 to 18 (median 13) years. They underwent a total of 68 interventions including surgical synovectomy (n=28), radionuclide synovectomy (n=33) and corticosteroid instillation (n=7). The necessity of a repeat intervention was used as a criterion of successful treatment.

RESULTS

In the group of surgical synovectomies, 22% of the patients required repeat operations, in the group of radiation synovectomy, this was 9% and, in the group treated with corticosteroids, this was 43%. The average hospitalisation time was 50 days for surgical procedures (19-133 days) and 7 days for radiation synovectomy procedures (4-13 days).

DISCUSSION

In 1994 Merchan presented seven excellent or good results in a group of 10 knees evaluated 1 year after treatment with methylprednisolone. Six years later he reported that "five years after completion of treatment, all results of the observed patients were poor". Generally, corticosteroids will reduce synovitis in the majority of patients but the effect is temporary. A complete remission is a very rare situation under corticosteroid treatment. The experience with surgical synovectomies is not recent and this method is described as carrying a high risk of complications and requiring a high amount of coagulating factor consumption. There are several recent reports on the application of Yttrium-90: in Madrid they evaluated treated joints (knees, ankles and elbows, n = 66) in 44 patients aged from 9 to 39 years. The results were good in less than half of the knees and ankles. The treatment of elbows was more successful. It was recommended to perform synoviorthesis at the early stages of synovitis. In Israel, they reported that a decrease in the number of bleeding episodes was achieved in 80% of 115 patients treated with Yttrium-90; in 15% of them, bleeding in the treated joints stopped completely. In Izmir, Yttrium was used in the treatment of knees, elbows, ankles and also shoulders in children and young adults (3-25 years). The method was found to be safe and effective. Brazilian authors have experience with the treatment of knees, ankles, elbows and shoulders too; they have concluded that this method represents an important resource for the treatment of chronic haemophilic synovitis and markedly reduces joint bleeding frequency and pain, irrespective of the radiographic stage and inhibitor status. While the European Association of Nuclear Medicine (EANM) recommend using 186Re-sulfide for treatment in medium-sized joints, Chinese authors have published a study comparing the effect of using three different doses of 186Re-sulfide in the treatment of chronic synovitis in knees. Their patients have received an amount of radionuclide according to the thickness of their synovial layer measured on MRI, with the result that 22 patients exhibited significant reduction in synovial thickness. A reduction in the number of bleeding episodes was reached in 71% of the patients within an 18-month period. No significant differences were found among the groups receiving different radioactivity doses. In Turkey, 35 elbows, 26 ankles and two shoulders in 49 patients aged between 3 and 30 years were treated with 186Re. The patients were followed up from 6 months to 3 years. At 6 months after the procedure, 81% of the elbows and 86% of the ankles with grade II synovitis were free from bleeding, as well as 53% and 44% of the elbows and ankles with grade III synovitis, respectively.

CONCLUSIONS

Radiation synovectomy appears to be the method of choice in the treatment of recurrent bleeding in the joint cavity in people with haemophilia. The efficacy of surgical synovectomy is lower in comparison with radiation synovectomy. Risks associated with surgery and anaesthesia, the need of hospitalisation and a prolonged period of rehabilitation are bothering. On the contrary, the application of corticosteroids cannot be recommended as a good method to treat recurrent haemarthroses.

[Destruction of synovial pannus of antigen-induced arthritis by ultrasonic cavitation in rabbits]

OBJECTIVE

To optimize the conditions of ultrasonic irradiation and microbubble of ultrasound cavitation on destruction of synovial pannus of antigen-induced arthritis (AIA) in rabbits.

METHODS

Antigen-induced arthritis was successfully induced on bilateral knee joints of 85 rabbits. Each 10 AIA rabbits were divided into two groups to compare various peak negative pressures, different ultrasonic pulse durations, various pulse repetition frequencies, different irradiance duration, different dosages of microbubble contrast agents, different ultrasonic irradiance times. With intravenous infusion of Sonovue to the rabbits, ultrasonic irradiance was performed on the right knee joint using the above condition of ultrasound cavitation. At the day 1 after ultrasonic irradiance, MRI and pathological examination were employed to evaluate the optimal conditions.

RESULTS

The optimal parameters and conditions for ultrasonic irradiance included intermittent ultrasonic application (in 6 s intervals), 0.6 mL/kg of microbubble contrast agent, 4.6 MPa of ultrasonic peak negative pressure, 100 cycles of pulse duration, 50 Hz of pulse repetition frequency, 5 min of ultrasonic duration, 0.6 mL/kg of dosages of microbubble contrast agents and multi-sessional ultrasonic irradiance. After the ultrasonic irradiance, the thickness of right knee synovium measured by MRI was thinner than that of left knee and synovial necrosis was confirmed by the pathological finding.

CONCLUSION

Under optimal ultrasonic irradiation and microbubble conditions, ultrasonic cavitation could destroy synovial pannus of AIA in rabbits.

Preparation and pre-clinical study of 177Lu-labelled hydroxyapatite for application in radiation synovectomy of small joints

AIM

We present in this paper, the preparation and pre-clinical study of 177Lu-labelled hydroxyapatite for the application in radiation synovectomy of small sized joints.

METHODS

177Lu is an adequate radionuclide for therapy, having ability of simultaneously showing therapeutic effects and depicting images. Both hydroxyapatite particulates and 177Lu were prepared indigenously.

RESULTS AND CONCLUSION

Analysis of the gamma ray spectrum showed the radionuclide purity of 177Lu more than 99%. HA particles were synthesized and characterized by FTIR-ATR and X-ray diffractometry. XRD-Pattern generated by the product indicated that the chief inorganic phase of the sample is hydroxyapatite crystal. FTIR spectrum of HA powder calcined at 800°C for 1h showed all the bands that can be assigned to phosphate and hydroxyl groups in an apatite environment. Ca/P ratio was determined by ICP-OES. The Ca/P ratio of 1.68 determined for HA was about 0.6% above the stoichiometric ratio of 1.67. Particle size distribution pattern was obtained with the help of laser particle size analyzer and results showed that more than 80% of the particles bear the size in the range ideal for radiosynovectomy. 177Lu-labelled hydroxyapatite particulates were prepared with high radiochemical purity and yield. >95% labeling yield was achieved at pH 7. Labeled specie remained stable up to 18 days. In vitro stability >99% remained up to >one half life of 177Lu. Bio-evaluation of the 177Lu-HA particles was carried out by injecting approximate activities of 10 and 5 MBq (in 0.1 mL suspension) as intra-articular injection in the right knee joints of rabbit 1 and 2 respectively. Retention of activity was studied using images of the injected joints with the help of a gamma camera at various intervals. In all images no activity was visible in any organ other than knee joints. The retention of the 177Lu activity was followed for 772 hours (30.01 days). Leakage of activity was also assessed indirectly by estimating the residing time of radiopharmaceutical in the synovium. Half life of 177Lu-HA residing time in the knees was estimated to be 154 hours and 158 hours for rabbit-1 and rabbit-2 respectively. No significant extra articular leakage of the injected activity was observed over a period of one month post injection. Pre-clinical study of 177Lu-labelled hydroxyapatite indicated its potential for application in radiation synovectomy of small joints.

Dose calculation from a D-D-reaction-based BSA for boron neutron capture synovectomy

Monte Carlo simulations were carried out to calculate dose in a knee phantom from a D-D-reaction-based Beam Shaping Assembly (BSA) for Boron Neutron Capture Synovectomy (BNCS). The BSA consists of a D(d,n)-reaction-based neutron source enclosed inside a polyethylene moderator and graphite reflector. The polyethylene moderator and graphite reflector sizes were optimized to deliver the highest ratio of thermal to fast neutron yield at the knee phantom. Then neutron dose was calculated at various depths in a knee phantom loaded with boron and therapeutic ratios of synovium dose/skin dose and synovium dose/bone dose were determined. Normalized to same boron loading in synovium, the values of the therapeutic ratios obtained in the present study are 12-30 times higher than the published values.

Low level light effects on inflammatory cytokine production by rheumatoid arthritis synoviocytes

BACKGROUND AND OBJECTIVE

Low level light therapy (LLLT) is being evaluated for treating chronic and acute pain associated with rheumatoid arthritis (RA) and other inflammatory diseases. The mechanisms underlying the effectiveness of LLLT for pain relief in RA are not clear. The objectives of this study were to determine whether LLLT decreased production of pro-inflammatory cytokines by cells from RA joints, and, if so, to identify cellular mechanisms.

STUDY DESIGN/MATERIALS AND METHODS

Synoviocytes from RA patients were treated with 810 nm radiation before or after addition of tumor necrosis factor-alpha (TNF-alpha). mRNA for TNF-alpha, interleukin (IL)-1beta, IL-6, and IL-8 was measured after 30, 60, and 180 minutes using RT-PCR. Intracellular and extracellular protein levels for 12 cytokines/chemokines were measured at 4, 8, and 24 hours using multiplexed ELISA. NF-kappaB activation was detected using Western blotting to follow degradation of IkappaBalpha and nuclear localization of the p65 subunit of NF-kappaB.

RESULTS

Radiation at 810 nm (5 J/cm(2)) given before or after TNF-alpha decreases the mRNA level of TNF-alpha and IL-1beta in RA synoviocytes. This treatment using 25 J/cm(2) also decreases the intracellular levels of TNF-alpha, IL-1beta, and IL-8 protein but did not affect the levels of seven other cytokines/chemokines. TNF-alpha-induced activation of NF-kappaB is not altered by 810 nm radiation using 25 J/cm(2).

CONCLUSIONS

The mechanism for relieving joint pain in RA by LLLT may involve reducing the level of pro-inflammatory cytokines/chemokines produced by synoviocytes. This mechanism may be more general and underlie the beneficial effects of LLLT on other inflammatory conditions.

Radiation synovectomy with (90)Yttrium, (186)Rhenium and (169)Erbium: a systematic literature review with meta-analyses

OBJECTIVE

To perform a systemic review and meta-analysis on the effectiveness of radiosynoviorthesis (RSO).

METHODS

A search of medical databases was conducted. Criteria for inclusion: articles in English, minimum follow-up of 6 months, specification of joint disease, reported outcome of at least 5 RSOs. The studies were scored for quality by the Oxford Centre of Evidenced-based Medicine Levels of Evidence, from 1 to 4.

RESULTS

Twenty-one (21) studies were included (3 quality 1b, 5 2b and 13 4), analysing 169Erbium/186Rhenium-RSO used predominantly in small joints and 49 (1 quality 1b, 10 2b and 38 4) on 90Yttrium-RSO used predominantly in knee joints. The reported success rates of 169Erbium/186Rhenium-RSO ranged from 69-100% at 6 months, and from 54-100% at > or =12 months; for 90Yttrium they were 24-100% and 29-94%, res-pectively. Studies comparing the effect of RSO with that of glucocorticoid (GC) or saline injection alone were pooled. At 6 months, the pooled odds ratio favouring RSO of the knee with Yttrium over control is 4 (confidence interval (CI) 95% 1.2-14), p=0.02, but at 12 months the ratio was 1.7 (CI95% 0.69-4), p=0.26. For RSO of small joints with Erbium/Rhenium compared to controls, the pooled odds ratio at 6 months is 2 (CI95% 0.66-6), p=0.22 and at 12 months 2 (CI95% 1.09-3.5), p=0.03.

CONCLUSION

Reported success rates of RSO are high, but differences in effect with GC injection are less evident, although there is marked heterogeneity in study design of the (small number of) comparative studies.

Lipoma arborescens; successfully treated by yttrium-90 radiosynovectomy

Although radiosynovectomy (RS) applications have been carried out for many years, clinical indications of this non-invasive procedure is thought to be limited probably due to the lack of information of clinicians. Clinicians' preferential indication for RS is the treatment-resistant synovitis of individual joints, i.e. despite systemic pharmacotherapy and intra-articular steroid injections. We present here a case of "lipoma arborescens" treated by yttrium-90, which is a rare intra-articular lesion characterized by villous proliferation of the synovial membrane and hyperplasia of subsynovial fat. The results of clinical, biochemical and hematological examinations, magnetic resonance (MR) imaging, arthroscopy and histological analysis have shown that the etiology was lipoma arborescens in a female patient, aged 36 having swelling and sometimes associating pain at her right knee for 4 years. We have applied to our patient's right knee RS with 185 MBq yttrium-90 colloid together with 40 mg of methylprednisolone acetate, although in our literature survey we have not met any similar case being treated with such indication. Even a year after the application, the patient has absolutely benefited from the treatment clinically, and this was also confirmed by comparative MR images (pre- and post-treatment). Consequently, we consider that Y-90 treatment might be applicable in suitable cases with lipoma arborescens.

Radiation Exposure of Hemophiliacs After Radiosynoviorthesis with 186Re Colloid

Very limited data are available in the literature on the doses of unwanted radiation that patients receive following treatment with radiosynoviorthesis (RSO).

OBJECTIVE

The aim of this study was to assess the radiation exposure after RSO with (186)Re colloid in hemophiliacs.

METHODS

This study involved 12 hemophiliacs who were treated for hemophilic joint disease with 14 RSOs by using (186)Re colloid. Whole-body scintigrams were performed 1, 6, and 24 hours and 3 and 7 days after RSO. Measurements, using a whole-body counter, were done immediately after scintigraphy, with the treated joint protected with a lead shield. The cumulative activity of (186)Re in the body and in the lymph nodes was calculated. The distribution of (186)Re in the body was determined by using the values for small colloids as proposed by the International Commission on Radiological Protection (ICRP) Publication 53. The computer code, OLINDA/EXM (Vanderbilt University, Nashville, TN), was used for the calculation of the internal dose. A constant distance of 1 m between the ankle joint and body organs, and of 0.33 m between the elbow or shoulder joint and body organs, was used to calculate the contribution of gamma radiation to the effective radiation dose.

RESULTS

The mean effective dose received by hemophiliacs after RSO with (186)Re colloid was 28 +/- 9 microSv/MBq of the activity injected into the joint. The patients received 0.8-3.7 mSv (1.9 +/- 0.8 mSv) owing to the leakage of (186)Re from the treated joint and its retention in the body. The highest doses were established in the spleen (26.0 +/- 10.7 mGy), the liver (17.6 +/- 7.2 mGy), and red marrow (3.0 +/- 0.8 mGy). The contribution of gamma radiation to the effective dose was less than 0.1 mSv in RSO of the ankle, 0.4 mSv in the elbow, and 0.6 mSv in the shoulder-joint treatment. The activity of (186)Re in the regional lymph nodes was noted in 4 of the 14 treatments. In these cases, the estimated average dose received by individual lymph nodes was 14.7 +/- 1.9 Gy.

CONCLUSIONS

RSO with (186)Re colloid is a safe treatment method. The effective dose received by patients after RSO by using (186)Re colloid is low, as are the radiation doses to the most exposed organs. If (186)Re is retained in the regional lymph nodes, the lymph node radiation dose would be high.

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.

Diffuse pigmented villonodular synovitis: preliminary results with intralesional resection and p32 synoviorthesis

Because of the high local recurrence rate associated with surgical resection alone, patients with diffuse intraarticular pigmented villonodular synovitis were treated with surgical resection followed by colloidal chromic P32 synoviorthesis. The medical records of nine consecutive patients treated in this manner were reviewed retrospectively to determine the recurrence rate of pigmented villonodular synovitis. All patients had either one or two surgical resections (arthroscopy in one patient, open resection in seven, arthroscopy and open resection in one). The involved joints included six knees and one each, ankle, elbow, and hip. Eight of the nine patients remained recurrence free at a mean followup of 38 months (range, 19-60 months) after surgery. One patient had a suspected asymptomatic recurrence documented by magnetic resonance imaging 29 months after surgery. Seven patients reported their normal activities as unrestricted. Five reported improved activity levels, one reported the activity level remained the same, and one reported activity as the same or better. None reported reduced activity levels. In these patients synoviorthesis with colloidal chromic P32 following gross resection of all obvious pigmented villonodular synovitis provided local disease control in all but one.

Estimation of radiation dose at various depths for commonly used radionuclides in radiosynoviorthesis in a tissue equivalent material

The purpose of the paper is to report on the dose estimation studies at various depths for the commonly used beta-emitting 90Y, 166Ho, 153Sm, 32p, and 177Lu radionuclides in a phantom fabricated using the poly methyl methacrylate tissue equivalent material having a density of 1.19 gm/cc, by using thermoluminescent dosemeters. GAFChromic MD-55 films were used to calculate the calibration factor for the thermoluminescent micro-rods used in our study. It is observed that 90Y delivers the highest dose at 1 mm amongst the radionuclides tested followed by 32p, 166Ho, 153Sm, and 177Lu, whereas the cumulative dose received by the joint was found to be more for 32P followed by 90Y, 166Ho, 153Sm, and 177Lu. The highest therapeutic range obtained is 3.1 mm for 153Sm amongst the tested radionuclides. The dose values obtained for all the above-mentioned radionuclides can serve as reference material for those researchers and clinicians who are interested in selection of the radionuclide for the type of joint treated and the amount of dose necessary to be delivered to the synovial membrane.

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.

Anti-inflammatory effect of linear polarized infrared irradiation on interleukin-1β-induced chemokine production in MH7A rheumatoid synovial cells

We examined the anti-inflammatory effect of infrared linear polarized light irradiation on the MH7A rheumatoid fibroblast-like synoviocytes (FLS) stimulated with the proinflammatory cytokine interleukin (IL)-1beta. Expression of messenger ribonucleic acids (mRNAs) encoding IL-8, RANTES (regulated upon activation, normal T cell expressed and secreted), growth-related gene alpha (GROalpha), and macrophage inflammatory protein-1alpha (MIP1alpha) was measured using real-time reverse transcription polymerase chain reaction, and the secreted proteins were measured in the conditioned media using enzyme-linked immunosorbent assays. We found that irradiation with linear polarized infrared light suppressed IL-1beta-induced expression of IL-8 mRNA and, correspondingly, the synthesis and release of IL-8 protein in MH7A cells. This anti-inflammatory effect was equivalent to that obtained with the glucocorticoid dexamethasone. Likewise, irradiation suppressed the IL-1beta-induced expression of RANTES and GROalpha mRNA. These results suggest that the irradiation of the areas around the articular surfaces of joints affected by rheumatoid arthritis (RA) using linear polarized light may represent a useful new approach to treatment.

Evaluation of 90Y phosphate particles as a possible radiation synoviorthesis agent

BACKGROUND

90Y is one of the radioisotopes used extensively for therapy due to its favourable nuclear characteristics. Particles and colloids incorporating 90Y are being used for radiation synovectomy, especially in European countries.

METHODS

In our present work, 90Y phosphate particles were prepared and evaluated for use in radiation synovectomy. The radioactive particles were prepared by reacting carrier added 90YCl3 with phosphoric acid.

RESULTS

The radiolabelling yield obtained was >95%. The particles were found to be stable in saline for up to 7 days of study at 37 degrees C. Particle size analysis of inactive yttrium phosphate showed that most of the particles were in the size range of 2-20 microm. Biodistribution studies carried out by intra-articular injection of the particles into the knee joints of rats showed that approximately 99% of the particles were retained in the joints with negligible radioactivity in the major organs even at 48 h post-injection. Scintigraphic studies in rabbit showed that >99% of the radioactive particles were retained in the knee joint even at 96 h post-injection. No significant radioactivity above background was detected in the blood.

CONCLUSION

The promising results warrant further studies on 90Y phosphate particles for use in radiation synovectomy.

Microbubble-enhanced ultrasound exposure promotes uptake of methotrexate into synovial cells and enhanced antiinflammatory effects in the knees of rabbits with antigen-induced arthritis

OBJECTIVE

To evaluate whether microbubble-enhanced ultrasound (US) treatment promotes the delivery of methotrexate (MTX) into synovial cells and the enhanced antiinflammatory effects of intraarticular MTX therapy in a rabbit arthritis model.

METHODS

Arthritis was induced in both knees of 53 rabbits by immunization with ovalbumin. MTX including a microbubble agent was then injected into the left and right knee joints, and the right knees were exposed to US (MTX+/US+ group), while the left knees were not (MTX+/US- group). The knee joints were evaluated histologically in 7 rabbits at 5 time points up to day 56. Quantitative gene expression of interleukin-1beta (IL-1beta) in synovial tissue was measured on days 7 and 28. Eight rabbits were used for the measurement of MTX concentration in synovial tissue 12 hours after treatment. To evaluate the effect of microbubble-enhanced US treatment in the absence of MTX, only the microbubble agent was injected into the left and right knee joints of 10 rabbits with or without US exposure, and these animals were evaluated histologically on days 7 and 28.

RESULTS

The MTX concentration in synovial tissue was significantly higher in the MTX+/US+ group than in the MTX+/US- group. Synovial inflammation was less prominent in the MTX+/US+ group compared with the MTX+/US- group, judging from the results of the histologic evaluation and the gene expression levels of IL-1beta in synovial tissue. It also appeared that microbubble-enhanced US exposure itself did not affect inflammation.

CONCLUSION

Microbubble-enhanced US exposure promoted the uptake of MTX into synovial cells, which resulted in enhancement of the antiinflammatory effects of the intraarticular MTX injection. These results suggest that application of this technique may have clinical benefit.

Optimization of pulsed electromagnetic field therapy for management of arthritis in rats

Studies were undertaken to find out the effects of low frequency pulsed electromagnetic field (PEMF) in adjuvant induced arthritis (AIA) in rats, a widely used model for screening potential therapies for rheumatoid arthritis (RA). AIA was induced by an intradermal injection of a suspension of heat killed Mycobacterium tuberculosis (500 mug/0.1 ml) into the right hind paw of male Wistar rats. This resulted in swelling, loss of body weight, increase in paw volume as well as the activity of lysosomal enzymes viz., acid phosphatase, cathepsin D, and beta-glucuronidase and significant radiological and histological changes. PEMF therapy for arthritis involved optimization of three significant factors, viz., frequency, intensity, and duration; and the waveform used is sinusoidal. The use of factorial design in lieu of conventional method resulted in the development of an ideal combination of these factors. PEMF was applied using a Fransleau-Braunbeck coil system. A magnetic field of 5 Hz x 4 muT x 90 min was found to be optimal in lowering the paw edema volume and decreasing the activity of lysosomal enzymes. Soft tissue swelling was shown to be reduced as evidenced by radiology. Histological studies confirmed reduction in inflammatory cells infiltration, hyperplasia, and hypertrophy of cells lining synovial membrane. PEMF was also shown to have a membrane stabilizing action by significantly inhibiting the rate of release of beta-glucuronidase from lysosomal rich and sub-cellular fractions. The results indicated that PEMF could be developed as a potential therapy in the treatment of arthritis in humans.

Scintigraphy in rheumatic diseases

The aim of this review is to summarise the clinical role of nuclear medicine in rheumatology taking into consideration the most specific diagnostic applications and other worthwhile therapeutic contributions. Traditional bone scintigraphy and recent inflammation-targeting radiopharmaceuticals, such as radiolabelled leucocytes and immunoscintigraphy, now allow us to obtain highly sensitive total-body and tomographical imaging information that can be used for the diagnosis of osteoarticular disease. The most common extra-articular manifestations of rheumatic diseases due to digestive, central nervous, respiratory and cardiovascular system involvement can be diagnosed by specific scintigraphic methods. Radiosynovectomy plays an important role in providing effective treatment for some joint diseases that are resistant to pharmacological therapy. Diagnostic and therapeutic applications of nuclear medicine show the highest efficacy in the early phase of rheumatic diseases. In more advanced stages, scintigraphical techniques play a complementary role to radiographical investigations in the assessment of prognosis and therapy efficacy.

In vivo gene delivery to articular chondrocytes mediated by an adeno-associated virus vector

PURPOSES

(1) To investigate the efficiency of direct in vivo adeno-associated virus (AAV) vector-mediated gene transduction to chondrocytes in relation to normal and injured articular cartilage. (2) To evaluate the effects of ultra-violet light-activated gene transduction (LAGT) in chondrocytes in vivo. (3) To determine dissemination of active rAAV vector after intra-articular administration.

METHODS

Rabbit knees with either normal or injured cartilage received an intra-articular injection with 1.5x10(12) infectious rAAV-eGFP particles. The right knees received rAAV-eGFP alone, whereas the left knees were given LAGT-treatment. The transduction efficiencies were determined at 1 and 3 weeks after infection by fluorescence-activated cell scanning. The occurrence of active shedding was monitored in serum and various tissues.

RESULTS

After 1 week, 7% of the chondrocytes in normal cartilage were transduced by direct rAAV transduction technique. Chondrocytes in cartilage defects demonstrated higher transduction rates compared to chondrocytes in normal cartilage. LAGT increased the cellular eGFP expression in the internal zones to 12%, but did not have any effect in the external zones in defects. Finally, infectious particles were not detected in either serum or tissue samples.

CONCLUSIONS

Direct rAAV-mediated gene transfer in vivo to articular chondrocytes is possible. LAGT improves rAAV transduction of chondrocytes in vivo but appears to have a very limited range of effect induction. Expression of eGFP was not determined in other tissues than synovium and cartilage in the treated joints.

Characterization of the ideal candidate for knee radiosynoviorthesis treatment in patients with rheumatoid arthritis

OBJECTIVES

(1). To identify the main parameters that positively influence the outcome of knee radiosynoviorthesis (RSO) in patients with rheumatoid arthritis (RA) and (2). to determine the ideal candidate for this procedure.

METHODS

We considered 80 knees (in 57 patients) that had undergone follow-up for at least 5 years and/or prosthesis implantation after RSO treatment. The parameters evaluated included age, gender, oligo-articular or polyarticular involvement, disease progression, radiological joint damage (Larsen scale), instability and/or axial deviation, body mass index (BMI), and psychological motivation for prosthesis implantation.

RESULTS

Knee Larsen stage IV, presence of instability-axial deviation, disease progression, psychological motivation to the surgical replacement and BMI higher than the 85th percentile were associated with a negative outcome for RSO (prosthesis implantation).

CONCLUSIONS

The ideal candidate for the RSO treatment is a patient with a low Larsen stage, no instability and/or axial deviation and a BMI below the 85th percentile. A patient's psychological motivation for the treatment should be evaluated before the RSO procedure.

Radiation synovectomy of the ankle with 75 MBq colloidal 186rhenium-sulfide: effect, leakage, and radiation considerations

OBJECTIVE

In a retrospective study we evaluated the effect, duration of effect, and safety of radiosynoviorthesis of the ankle in patients with persistent synovitis, refractory to disease modifying antirheumatic drugs (DMARD) and intraarticular glucocorticoid injections. We estimated leakage and dose to target and non-target organs.

METHODS

Radiation synovectomy was performed by injection of 75 MBq 186rhenium colloid and 20 mg triamcinolone-hexacetonide mixed in a volume of about 1.5 ml. About 24 hours after injection, leakage of the radionuclide was measured with a single-head gamma camera, with views of the ankle joint, regional (inguinal) lymph nodes, and liver. Leakage was expressed as counts in the target region of interest corrected for background relative to total counts corresponding with percentage of injected dose. The effect of radiosynoviorthesis was scored into 3 categories: (1) No effect, i.e., persistent synovitis or only minimal reduction of swelling and/or pain, or the need of intraarticular glucocorticoid injection within 3 months or arthrodesis of the treated joint within 6 months. (2) Moderate effect, i.e., significant reduction of swelling, pain, and improvement of function. (3) Good effect, i.e., complete or almost complete remission of synovitis.

RESULTS

The mean age of patients (28 women, 12 men) at the time of treatment was 58 years (range 33-76); 54 consecutive procedures in ankles of the 40 patients were evaluated. No effect was found in 12 of 54 (22%) treated joints; moderate effect in 12 (22%), with a mean duration of effect of 34 months (range 12-49); and good effect in 30 (56%), with a mean duration of effect of 41 months (range 21-75). Mean effect-duration did not differ significantly between the moderate and good effect groups. Mean leakage did not differ significantly between the effect groups.

CONCLUSION

Radiation synovectomy of the ankle is a safe and effective treatment in persistent synovitis, although all patients eventually experienced recurrence of arthritis.

MR evaluation of radiation synovectomy of the knee by means of intra-articular injection of holmium-166-chitosan complex in patients with rheumatoid arthritis: results at 4-month follow-up

OBJECTIVE

To determine whether MRI is able to demonstrate the effect of radiation synovectomy after the intra-articular injection of holmium-166-chitosan complex for the treatment of rheumatoid arthritis of the knee.

MATERIALS AND METHODS

Fourteen patients aged 36-59 years were treated with 10-20 mCi of holmium-166-chitosan complex. A criterion for inclusion in this study was the absence of observable improvement after 3- or more months of treatment of the knee with disease-modifying anti-rheumatic drugs. MR images were acquired both prior to and 4-months after treatment. Clinical evaluation included the use of visual analog scales to assess pain, and the circumference of the knee and its range of motion were also determined. MR evaluation included measurement of the volume of synovial enhancement and wall thickness, the amount of joint effusion, and quantifiable scoring of bone erosion, bone edema and lymph nodes.

RESULTS

Visual analog scale readings decreased significantly after radiation synovectomy (p < 0.05). MRI showed that joint effusion decreased significantly (p < 0.05), and that the volume of synovial enhancement tended to decrease, but to an insignificant extent (p = 0.107).

CONCLUSION

The decreased joint effusion noted at 4-month follow-up resulted from radiation synovectomy of the rheumatoid knee by means of intra-articular injection of holmium-166-chitosan complex.

Radionuclide synovectomy and chronic haemophilic synovitis in Asians: a retrospective study

Radionuclide synovectomy has been identified as the procedure of choice in treating chronic haemophilic synovitis among Caucasian populations. Its effectiveness among East Asians has not been studied. A retrospective study was carried out on 12 Asian haemophiliacs who underwent 12 radionuclide synovectomies. The average follow-up was 30.7 months (range 6-55) for primary procedures. 32P chromic phosphate and 188Re-tin colloid were injected into target joints according to protocol. There was a significant 80% decrease in the median frequency of haemarthrosis from 1.4 per month (range 0.2-7.0) to 0.25 per month (range 0.0-1.8) (P<0.05). Half of the patients had excellent results by 1 year of synovectomy. The median factor usage for target joint haemarthrosis postsynovectomy was 792 units per month (range 0-3209) reduced significantly from a presynovectomy level of 1452 units per month (range 306-7125) (P<0.05). Patients also reported a reduction in joint pain scores, and an improvement in joint mobility and quality of life. The majority of patients were satisfied with the overall outcome of radionuclide synovectomy. Radionuclide synovectomy appears to be effective in reducing the incidence of target joint haemarthrosis and quantity of factor usage for such bleeds among Asians with haemophilic synovitis.

Comparison of Tc-99m HIG and three-phase Tc-99m MDP bone scintigraphy for evaluating the efficacy of Yttrium-90 silicate radionuclide synovectomy

PURPOSE

The aim of this study was to compare Tc-99m human immunoglobulin (HIG) and three-phase Tc-99m MDP bone scintigraphy for the assessment of the efficacy of Y-90 silicate therapy in rheumatoid knee synovitis.

MATERIALS AND METHODS

Fifteen patients with rheumatoid arthritis and chronic persistent synovitis in 23 knee joints had radionuclide synovectomy with Y-90 silicate. The patients underwent imaging before and 3, 6, 9, and 12 months after therapy using clinical evaluation, Tc-99m HIG scintigraphy, and three-phase Tc-99m MDP bone scintigraphy.

RESULTS

In the 13 of 23 knee joints that showed successful clinical results with Y-90 therapy, the Tc-99m HIG index values obtained 3 months after radionuclide synovectomy were significantly lower than the pretreatment index values (P < 0.001). In the same 13 joints, the Tc-99m MDP index values (in the blood-pool and delayed phases) before and 3 months after therapy were statistically similar. Six months after injection, these values were significantly lower in both the blood-pool (P < 0.001) and late (P < 0.05) phases in all 13 joints. In the other 10 of 23 knee joints that did not respond to treatment, the Tc-99m MDP and Tc-99m HIG index values were statistically similar before and after Y-90 therapy.

CONCLUSIONS

Based on these findings, Tc-99m HIG scintigraphy appears to be a valuable method that complements clinical assessment of the efficacy of Y-90 silicate therapy in rheumatoid knee synovitis, starting in the early post-treatment period. However, three-phase Tc-99m MDP bone scintigraphy may be valuable in the late postsynovectomy period.

Yttrium90 synovectomy in the management of chronic knee arthritis: a single institution experience

Radiation synovectomy (RS) has been used to treat chronically inflamed joints refractory to treatment using conventional agents. In RS, the radioactive isotope is concentrated in the synovial membrane from the injected colloid suspension, where it exerts its activity. However, despite numerous reports confirming its safety and efficacy, this procedure is not widely practised. In the Singleton Hospital NHS Trust, yttrium(90) (Y(90)) RS has been practised since 1990 for refractory synovitis. In this study, we analyse the results of therapy and complications in 38 joints so treated. Doses of 10 mCi were used in the majority of patients. Most responses were apparent by 6 months following the procedure. Altogether, 68% of the treated joints showed satisfactory response at 3 years, with 29% having all symptoms under control beyond 3 years. In three patients, there was evidence of minor pigmentation at the injection site. Two patients had extravasation of the isotope and needle track ulcers, which were recorded as major toxicity. We find Y(90) radiosynovectomy to be safe, quick, and effective in the management of patients with refractory synovitis. The efficacy of RS should be tested in randomised clinical trials involving large numbers of patients.

Does yttrium radiosynovectomy increase the risk of cancer in patients with rheumatoid arthritis?

OBJECTIVE

To study the long term risk of cancer in patients with rheumatoid arthritis (RA) who have been treated with yttrium.

METHODS

The medical record numbers of 1228 patients with RA who were admitted to hospital in 1979-85 were identified in the database of Jyväskylä Central Hospital. Radiosynovectomy of the knee joint was performed in a total of 143 patients using yttrium-90 silicate during the years 1970-85, while 1075 did not receive yttrium radiosynovectomy; 10 received yttrium treatment later than 1985 and were excluded from the analysis. The Finnish Cancer Registry database was used to examine whether the subjects had cancer during the follow up from 1979 until the end of 1999.

RESULTS

Nine cases of cancer were found among the patients who had received yttrium, whereas the expected number based on the incidence among the population in the region was 14.9. The standardised incidence ratio of cancer was 0.6 (95% confidence interval (CI) 0.3 to 1.1) for the patients who received yttrium, and 1.1 (95% CI 0.9 to 1.3) for the patients who did not receive yttrium.

CONCLUSIONS

Yttrium treatment did not increase the risk of cancer.

Analysis of lapine cartilage matrix after radiosynovectomy with holmium-166 ferric hydroxide macroaggregate

OBJECTIVE

To study the short and long term effects of radiosynovectomy on articular cartilage in growing and mature rabbits.

METHODS

The articular cartilage of the distal femurs of rabbits was examined four days, two months, and one year after radiosynovectomy with holmium-166 ferric hydroxide macroaggregate ([(166)Ho]FHMA). Arthritic changes were evaluated from histological sections by conventional and polarised light microscopy, and glycosaminoglycan measurements using safranin O staining, digital densitometry, and uronic acid determination. Proteoglycan synthesis was studied by metabolic [(35)]sulphate labelling followed by autoradiography, and electrophoretic analysis of extracted proteoglycans. Northern analyses were performed to determine the mRNA levels of type II collagen, aggrecan, and Sox9 in cartilage samples.

RESULTS

Radiosynovectomy had no major effect on the histological appearance of articular cartilage in mature rabbits, whereas more fibrillation was seen in [(166)Ho]FHMA radiosynovectomised knee joints of growing rabbits two months after treatment, but not after one year. Radiosynovectomy did not cause changes in the glycosaminoglycan content of cartilage or in the synthesis or chemical structure of proteoglycans. No radiosynovectomy related changes were seen in the mRNA levels of type II collagen, whereas a transient down regulation of aggrecan and Sox9 mRNA levels was seen in young rabbits two months after [(166)Ho]FHMA radiosynovectomy.

CONCLUSIONS

[(166)Ho]FHMA radiosynovectomy caused no obvious chondrocyte damage or osteoarthritic changes in mature rabbits, but in growing rabbits some transient radiation induced effects were seen--for example, mild cartilage fibrillation and down regulation of cartilage-specific genes.

Preparation of Holmium-166 Labelled Macroaggregates for radionuclide synovectomy

BACKGROUND

Radionuclide synovectomy (radiation synovectomy) is an alternative method that cures patients with rheumatoid arthritis diseases without surgery. During treatment, the suspension of the (166)Ho-macroaggregates radioactive particles ((166)Ho-MA) is administrated via intra-articular injection into the target joint to destroy the inflamed synovium.

MATERIAL AND METHODS

The isotope of (166)Ho (E(beta) max = 1.84 MeV, T((1/2)) = 26.8 hr) was prepared by the (165)Ho(n, gamma)(166)Ho reaction in the LWR-15 nuclear reactor (8-10 MW) using approximate neutron flux 10(14) cm-2s-1.

RESULTS

The particles of Ho-Macroaggregates with suitable dimension 1-20 microm and the mean diameter of 8.5 microm were prepared. High in-vitro stability was obtained after incubation of neutron-irradiated Ho-Macroaggregates in saline solution (0.9% NaCl). The in-vivo stability on rats was verified as well.

CONCLUSIONS

High in-vivo and in-vitro stability as well as supporting gamma radiation of Ho-166 make the Macroaggregates a prospective agent for radionuclide synovectomy. The method of preparation is relatively easy and allows for the production of particles of a suitable dimension with a sufficient amount of radioactivity of Ho-166 for the treatment of the rheumatoid arthritis.

Radiation synovectomy with (166)Ho-ferric hydroxide: a first experience

Radiation synovectomy (RS) is indicated when conventional pharmacologic treatment of chronic synovitis has not relieved its symptoms. The use of radionuclides that are bound to ferric hydroxide (FH) particles has been shown to be effective and safe for this procedure. (166)Ho-FH macroaggregates offer promising properties for RS but there is a lack of clinical data. We investigated the efficacy and safety of (166)Ho-FH in a prospective clinical trial in patients suffering from chronic synovitis.

METHODS

Twenty-four intraarticular injections were performed in 22 patients receiving a mean activity of 1.11 GBq (range, 0.77-1.24 GBq) (166)Ho-FH. Blood activity measurements and monitoring of activity distribution were performed by whole-body gamma-camera imaging for control of leakage 3 and 24 h after injection of (166)Ho-FH. The patients were evaluated clinically before RS, 1 wk and 1 mo after the treatment, and thereafter in 3-mo intervals by assessing joint effusion, pannus, local pain, range of motion, and the patient's satisfaction.

RESULTS

In 18 of 24 treatments, no leakage to nontarget organs was visible, whereas small amounts of activity could be detected in the local inguinal lymph nodes in 6 patients and to the lungs and to the liver in 1 patient (<0.1%). In all cases leakage to the lymph nodes was <1%. Leakage to the blood was negligible. Clinically, 17 patients (71%) exhibited a complete or partial response.

CONCLUSION

RS with (166)Ho-FH was safe and effective in patients with chronic synovitis of different origin. Controlled clinical trials are necessary to evaluate the therapeutic efficacy and safety compared with the treatment with other radionuclides and glucocorticosteroids.

Experimental radiation synovectomy in rabbit knee with holmium-166 ferric hydroxide macroaggregate

Holmium-166 ferric hydroxide macroaggregate (Ho-166 FHMA) particles possess two important properties for radiosynovectomy; relatively short half-life of the radioisotope and appropriate carrier size. Both these minimize radioactive leakage from the treated joint. This study was conducted to assess the effects of Ho-166 FHMA on synovium and synovial fluid in rabbit knee joints. Whole-knee autoradiography was utilized to determine distribution of radioactivity after intra-articular Ho-166 FHMA injection. Intra-articular injection of Ho-166 FHMA resulted in focal acute radiation necrosis in synovial lining but no hyperplasia of synoviocytes. Later, subsynovial fibrosis became evident. White blood cell and total protein levels in the joint fluid were elevated because of intra-articular inflammation due to the acute effects of radiation. Whole knee autoradiograms showed uneven distribution of the radionuclide along the synovium and extraarticular leakage on the third day after treatment.

[Study of radiation synovectomy using (188)Re-Sulfide in hemophilic arthritis]

OBJECTIVE

To study the effectiveness of radiation synovectomy with (188)Re-sulfide.

METHODS

Twenty rabbit models of joint synovitis were injected intra-articularly with different doses of (188)Re-sulfide from 7.4 to 37.0 MBq. By pathological examination, the effects of (188)Re-sulfide on synovium and cartilage were evaluated. Clinically, 10 joints of 7 cases of hemophilic arthritis with (188)Re-sulfide radiation synovectomy were performed. MRI was taken before and after the synovectomy to evaluate the treatment effects.

RESULTS

In rabbit models, when (188)Re-sulfide dose larger than 14.8 MBq, the radiation effect on synovitis was remarkable, including thinning the thickened synovium and reducing the inflammatory cells. When radio-activity dose increased to 37.0 MBq, pathological damage was noted in cartilage. Clinical trial demonstrated that radiation synovectomy by (188)Re-sulfide could reduce the frequencies of intra-articular hemorrhage. MRI showed that edema and villi reduced.

CONCLUSIONS

Radiation synovectomy using (188)Re-sulfide is effective on synovitis in hemophilic arthritis.

[Local radiotherapy in combined treatment of rheumatoid arthritis]

AIM

To study efficiency in rheumatoid arthritis (RA) of local radiotherapy methods: radionuclide synovectomy (RS), x-ray therapy (XRT) and local gamma-therapy (LGT) proposed by the authors.

MATERIAL AND METHODS

175 patients with RA received local radiotherapy on the knee joints. The patients were divided into three groups comparable by age, sex and disease characteristics receiving RS, XRT and LGT. The patients were for the most part women over 45 years with RA (duration 5 years and longer), polyarthritis, the disease x-ray stage II, moderate activity.

RESULTS

RS was most effective of the above methods, especially in long-term period. It produces antiinflammatory and immunosuppressive action. The new method, LGT, was effective in more than half the patients. It is antiinflammatory and immunosuppressive. XRT was the less effective of the three methods as it has only nonspecific antiinflammatory action.

CONCLUSION

Local radiotherapy enhances efficacy of RA treatment. RS and LGT produce immunosuppressive and antiinflammatory actions while XRT has only antiinflammatory action.

In vitro studies of a photo-oxidized bovine articular cartilage

Bovine articular cartilage was photo-oxidized and cultured with native articular bovine cartilage and synovial membrane to study the interaction between these tissues mimicking the physiological situation in the joint. The photo-oxidation was applied as a pretreatment of cartilage for future use in cartilage resurfacing procedures in joints. Properties of the transplant were assessed by testing the production of local mediators, such as nitric oxide (NO) and prostaglandin E2 (PGE2), and neutral metalloproteinase activities under normal conditions and after stimulation with various stimulants representative of inflammatory changes in pathophysiological conditions. Unlike normal cartilage photo-oxidized cartilage did not release significant amounts of NO and PGE2 and showed less gelatinolytic and caseinolytic activity compared to native bovine articular cartilage. Enzyme activity of the combined cultures was at a level intermediate between that of photo-oxidized cartilage and native cartilage cultures alone. In contrast to normal cartilage, living chondrocytes were not visible in photo-oxidized cartilage using live/dead staining. These results indicate, that the photo-oxidized cartilage may have a beneficial effect on adjacent native host cartilage and therefore be a suitable transplant for use in in vivo experiments.

Preparation and studies with 90Y-labelled particles for use in radiation synovectomy

90Y-FHMA (Ferric hydroxide macroaggregates) and 90Y-HA (hydroxyapatite) were prepared in >95% yield using 90Y from an in-house 90Sr-90Y generator. Most of the particles ranged from 5 to 20 microm in diameter and retained radiochemical purity > 95% in human serum for at least 7 days at 37 degrees C. Gamma camera imaging of normal rabbits after intraarticulation of the particles showed complete retention of activity within the knee cavity with no measurable radioactivity leaching out of the joints over a 96 hour period.

Recent advances in radionuclide therapy

A variety of radionuclides continue to be investigated and/or clinically used for different therapeutic applications in nuclear medicine. The choice of a particular radionuclide with regard to appropriate emissions, linear energy transfer, and physical half-life is dictated to a large extent by the character of the disease (eg, solid tumor or metastatic disease) and by the carrier used to selectively transport the radionuclide to the desired site. An impressive body of information has appeared in the recent literature that addresses many of these considerations. This article summarizes and discusses the many recent advances and the progress in the clinical applications of therapeutic radionuclides in relatively new and developing areas, such as radioimmunotherapy, peptide therapy, intravascular therapy to prevent restenosis, radiation synovectomy, and bone malignancy therapy. Projections are made as to the future directions and progress in these areas. The crucial issue of a reliable, year-round supply of new and emerging therapeutic radionuclides in quantities sufficient initially for research, and then for routine clinical use, is a very worthy goal which, in the United States, remains to be achieved.

Chemical synovectomy in haemophilia: status and challenges

Chemical synovectomy has been used for the last three decades as an alternative for surgical synovectomy in the treatment of chronic haemophilic synovitis. Comparable results have been obtained with the many different radionuclides used: decreased bleeding, decreased pain and stable range of motion, in more than 50% of treated patients. Yttrium 90Y and Phosphorus 32P seem to be the isotopes of choice. Osmic acid and rifampicine have been used in a relatively small number of subjects. Global result of treatment with these two pro-ducts seems to be less favourable than with radionuclides. Late effects of chemical synovectomy are not known.

The effect of radiation synovectomy in patients with persistent arthritis: a prospective study

OBJECTIVE

To investigate and compare the effects of radiation synovectomy of various joints in a rheumatological practice.

METHODS

Consecutive patients referredfor radiation synovectomy to Medical Center Alkmaarfrom 1993 till 1996 were analyzed (n = 138). Patients had to have persistent arthritis despite at least two intra-articular glucocorticoid injections with 20 mg triamcinolone hexacetonide. The knees were treated with 185 MBq Yttrium-90; shoulders, elbows, wrists, hips and talocrural joints received 185 MBq Rhenium-186 and meta-carpophalangeal joints and proximal interphalangeal joints 37 MBq Erbium-169. The radionuclide injection was followed by injection of 20 mg triamcinolone in order to prevent flare-up of synovitis (due to chemical irritation) and needle-track burn. The clinical effect was assessed by evaluating VAS pain (0-10 point scale), functional disability, tenderness and swelling of the treated joint and patient's and physician's global assessments of the effect of therapy (each on a 4-point scale).

RESULTS

The overall success rate for radiation synovectomy one year after treatment was 70% with a significant improvement in the variables VAS pain, functional disability and joint tenderness and swelling, when compared to baseline values (p < 0.000001). Moderate to considerable satisfaction of patients and physicians one year after treatment was found for > 50% of cases. Wrists and shoulders were the joints with highest success rate of treatment, followed by the elbows. Lowest success rates were found for hips and ankles. In RA treatment was effective in 76% of cases whereas patients with OA exhibited a success rate of 50%. In RA all treated joints, except the ankles, exhibited a success rate of > or = 75%. No short-term clinical adverse side effects were noted.

CONCLUSION

Radiation synovectomy seems to be a successful treatment for persistent arthritis when other therapeutic modalities have failed.

Synovectomy with rifampicine in haemophilic haemarthrosis

The purpose of this paper was to assess the effectiveness of intra-articular injected rifampicine in haemophilic patients in order to achieve synovectomy by preventing repeated intra-articular bleeding. We have used this technique in haemophilic patients previously and reported our results on 13 cases [1]. Two hundred and fifty milligrams of rifampicine was injected into the elbow and ankle joints and 500 mg was injected into knee joints with 3-10 mL of lidocaine, depending on the joint size. The injections were repeated once a week for 7 weeks. Patients were only covered with antihaemophilic factor on the day of the injection at 30% above their coagulation level. We evaluated the results using two measures: subjective reports from the patient and objective assessment by the examiner. In the subjective reports the patient graded the results from their own perspective from 1 (poor) to 10 (excellent): 1-3, poor; 4-6, fair; 7-8, good; and 9-10, excellent. In the objective reports the grading was: excellent ('dry joint', full function, no haemarthrosis, no synovitis); good (clinical improvement, synovitis, reduction of haemarthroses, full function); fair synovitis (reduction of haemarthroses, no change in function); poor synovitis (persistent haemarthroses). This paper reports on the results of 38 patients with 39 joints with more that 3 years follow up, mean 1.8 years. There were 22 knees, nine elbows and eight ankles. Subjectively, there were excellent results in 21 joints (11 knees, six elbows and four ankles) good results in 15 joints (eight knees, three elbows and four ankles), fair results in two knees and a poor result in one knee. Objectively, results obtained were excellent in 20 joints (11 knees, six elbows and three ankles); good in 17 (nine knees, three elbows and five ankles); fair in one knee and poor in one knee.

Isotopic synovectomy with P-32 in paediatric patients with haemophilia

Isotopic synovectomy is being proposed as an option in the treatment of patients with haemophilic arthropathy. We present our experience with 11 paediatric patients who underwent 17, P-32 isotopic synovectomies for chronic haemophilic arthropathy. P-32 was injected into the joint per protocol, approved by the institutional review board. All our patients were male. Nine were factor VIII and two were factor IX deficient. The following joints were treated: ankle (n=10 procedures), elbow (n=5) and knee (n=2). The first procedure was performed on December 1993. None were human immunodeficiency virus positive. Mean age at the first procedure was 10.8 years (range, 5.2-15.2 years). Mean pretreatment joint clinical scores using the World Federation of Hemophilia guidelines for the ankle was 5.5 (SD +/- 2.3), the elbow 4.2 (+/-2.5), and knee 5.5 (+/-3.5); the corresponding post-treatment scores were 2.6 (+/-2.0), 1.4 (+/-0.5) and 2.5 (+/-3.5) respectively. Presynovectomy mean radiological scores using the Pettersson method were: ankle 1.8, elbow 1.8, and knee 1.5. A scoring system used in our centre for evaluating joints using magnetic resonance imaging (MRI) gave the following mean pretreatment scores: ankle 9.5, elbow 8.4, and knee 5.0. A marked decrease (an 80-100% decrease) in bleeding was seen in 13 of 17 procedures, and a moderate decrease (51-79% decrease) in two procedures, accounting for 85% reduction in bleeding into the target joints. The procedure was well tolerated and no untoward side-effects were noted as of May 1999, with a median follow-up of 40 months (range 19-65 months). None had any clinical evidence of cancer. Three patients had their joints retreated [elbow (one), ankle (two)]. These procedures were also well tolerated. In conclusion, in our study, isotopic synovectomy using P-32 appears to be feasible, safe and efficacious in the treatment of haemophilic arthropathy in paediatric patients who have been followed for a median of 40 months. As previously shown, MRI appears to give more detailed information about joint arthropathy than plain radiographs.