Distribution of Serum Radioiodinated Compounds in Euthyroid and Hyperthyroid Patients Following Hypophysectomy*

Hypophysectomy performed in 6 euthyroid patients for the treatment of cancer was followed by a changed pattern of distribution of radioiodinated compounds in the serum (after a tracer dose of I131). Radioactivity was present almost entirely in the iodide fraction, with virtually none in the thyronine fraction. In contrast, hypophysectomy performed in 2 hyperthyroid patients (1 of whom had ophthalmopathy) and 2 euthyroid patients with the ophthalmopathy of Graves′ disease was followed by a normal or hyperthyroid pattern of distribution of the iodinated compounds in the serum.