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.


METHODS
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.


CONCLUSIONS
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.
Li
Peiyong
P
Department of Nuclear Medicine, Rui Jin Hospital, Shanghai, PR China. peiyli@vip.sina.com
Yu
Junfeng
J
Chen
Gang
G
Jiang
Xufeng
X
Tang
Zhonghua
Z
Chen
Suyun
S
Jiang
Lei
L
Tang
Lin
L
Yin
Duanzhi
D
D000328:Adult; D000818:Animals; D002712:Chlorides / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D011379:Prognosis; D011817:Rabbits; D011868:Radioisotopes / Q000627:therapeutic use*; D011874:Radiometry / Q000379:methods*; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D012211:Rhenium / Q000627:therapeutic use*; D013440:Sulfides; D013585:Synovitis / Q000473:pathology* / Q000532:radiotherapy*; D016896:Treatment Outcome
D002712:Chlorides; D011868:Radioisotopes; D019275:Radiopharmaceuticals; D013440:Sulfides; C400124:rhenium sulfide; D012211:Rhenium