USE OF I-123 IN EARLY RADIO-IODIDE UPTAKE AND ITS SUPPRESSION IN CHILDREN AND ADOLESCENTS WITH HYPER-THYROIDISM

  • 1 January 1978
    • journal article
    • research article
    • Vol. 19  (9) , 985-993
Abstract
Absolute activity measurement of 123I by coincidence counting was used to study the early thyroidal iodide uptake in 20 hyperthyroid children. Patients were pretreated either with methimazole or propylthiouracil before injection of Na123I. The usual method of analysis of the early uptake was modified to account for a rapidly equilibrating compartment, to give thyroidal iodide trapping rate constant (K1) and absolute iodide uptake (AIU). The suppressibility of the early uptake by triiodothyronine (T3) was evaluated in some patients. The upper limit of normal for K1 was 0.03 min-1 and for AIU was 0.04 .mu.g/min. In the hyperthyroid subjects, K1 and AIU were in the hyperthyroid range before and after T3 suppression. For patients with suppressible uptake, remission from hyperthyroidism was maintained for 6 mo. to 2 1/2 yr. Only 2 patients with nonsuppressible uptake achieved remission from hyperthyroidism, perhaps because of coexistence of thyroiditis.

This publication has 1 reference indexed in Scilit: