The intra-articular distribution of 90yttrium does not influence the clinical outcome of radiation synovectomy of the knee.
OBJECTIVE
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.
Jahangier
Z N
ZN
Department of Rheumatology and Clinical Immunology F02.127, University Medical Center Utrecht, PO Box 85500, 3508 GA Utrecht, The Netherlands. njahangier@hotmail.com
van der Zant
F M
FM
Jacobs
J W G
JW
Riedstra
H G
HG
Gommans
G M M
GM
Verzijlbergen
J F
JF
Bijlsma
J W J
JW
van Isselt
J W
JW
D000328:Adult; D000368:Aged; D001168:Arthritis / Q000378:metabolism / Q000532:radiotherapy*; D001707:Biopsy, Needle; D003131:Combined Modality Therapy; D018592:Cross-Over Studies; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D007270:Injections, Intra-Articular; D007719:Knee Joint; D016014:Linear Models; D008099:Liver / Q000000981:diagnostic imaging / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D013154:Spleen / Q000000981:diagnostic imaging / Q000378:metabolism; D013583:Synovial Membrane / Q000378:metabolism*; D014222:Triamcinolone Acetonide / Q000031:analogs & derivatives / Q000627:therapeutic use; D015021:Yttrium Radioisotopes / Q000008:administration & dosage / Q000493:pharmacokinetics*
D005938:Glucocorticoids; D015021:Yttrium Radioisotopes; D014222:Triamcinolone Acetonide; C005900:triamcinolone hexacetonide