Thyroidal radioiodine uptake in hyperthyroid cats.

Thyroidal radioiodine uptake was measured in 10 healthy domestic cats and in 20 hyperthyroid cats. Compared with those in the healthy cats, the uptake curves in the hyperthyroid cats were characterised by elevated uptake and rapid thyroidal iodine turnover. For diagnostic purpose uptake measurements at 4 hours after administration of the tracer were found to be preferable to measurements at 24 hours or later.