Use of modern scintigraphic methods for the control of thyroid function in small laboratory animals

Modern szintigraphic methods like scanner- and gammacamera techniques have been used for the first time to diagnose the thyroid function of small laboratory animals. Both methods have been tested on completely or partially iodine-resected rats. Because the results concerning the gammacamera could be quantified they could be compared to those of the gammacounter as a reference method. Assuming a linear relationship between both methods a correlation coefficient of r = 0.97 (n = 32) could be calculated. The capacity of both the scanner and the gammacamera was high enough to show even small amounts of residual thyroid tissue. Therefore both methods are extremely suitable for the diagnosis of the thyroid function. Using them as a control of the iodine-resection of the thyroidea a control group of animals is not necessary and, therefore, less animals are required. With regard to the narcosis of heavily hypothyroid animals it must be noted that the usually pentobarbital dosis must at least be reduced by one third. (author)