Development and clinical application of part body neutron activation analysis using Californium-252

Californium 252 sources were used in a clinical environment for neutron activation analysis studies for a period of 2 1/2 years. During this period changes in part body calcium in bone, in response to different treatment regimes, were measured in patients suffering from primary or secondary bone disease. Measurements were performed on peripheral bone, in 252 particular the forearm, using two sources of Cf, minimum total activity 56 mCi, and a purpose built partial body counter. Optimisation of the irradiation geometry and the patient irradiation programme enabled calcium measurements to be performed with a precision of between 1.5% and 1.8% and a bone dose less than 3 rem. The following clinical studies were undertaken: the effect of 1-oc-hydroxycholecalciferol on 19 patients under going chronic haemodialysis, the use of vitamin D2 or D3 in the treatment of 33 patients with potential anticonvulsant osteomalacia, the effect of lithium carbonate in 15 patients with manic depression and the efficacy of conventional treatments in combating thyrotoxic osteodystrophy. Apparatus was also developed to measure calcium 252 changes in the lumbar spine. Two Cf sources of total activity 200 mCi were used for irradiation and a whole body counter for detection of the induced activity. A precision of 2% was obtained for patient measurements, with a bone dose of 1.3 rem