Control Of The Biodistribution And Biokinetics Of 165-Dysprosium-Ferric-Hydroxide After Radiation Synovectomy Using The Clinical Whole-Body Counter In The General Hospital Vienna

Radiation synovectomy is suggested to be an alternative to surgical treatment. The aim of this study was to evaluate the application of the whole-body counter in the General Hospital Vienna for the study of the biodistribution and biokinetics of 165-dysprosium-ferric-hydroxide (Dy-165-DFH)During this study it was possible to measure 42 patients, who were treated with Dy-165-DFH. The applied activity ranged from 520 MBq to 12955 MBq. The emission of gamma-radiation with an energy of 95 keV is used to monitor the kinetic distribution of Dy-165 by performing activity profiles with the whole-body counter 2, 4 and 6 hours after injection. The doses to non-target organs were calculated using the software MIRDOSE II.In 32 patients no leakage could be monitored. In 3 patients a concentration of leakage was detected in the urinary bladder, in 2 patients a leakage was detected in the liver and in 6 patients a small leakage was detected in the inguinal lymphatic nodes of the treated legs. Using a whole-body counter activity leakage could be detected with much higher sensitivity than by using a gamma camera Biodistribution of Dy-165-DFH could be determined, leakage could be localised and related to organs.