Effect of immobilization on retention of 90Y.

In this study the distribution of the Bremsstrahlung radiation resulting from the absorption of f6 particles was evaluated immediately after the intra-articular injection into the knee of 90Y and subsequently at intervals over the next 3 days. The later results were compared with the original patterns in individual patients. In all the cases in this series the knee was immobilized immediately after the injection and kept enclosed in a plaster of Paris splint for the next 3 days. If there are any real differences between our results and those described in other centres, they may be related to this period of immobilization.