The Thyroid Scintigram

Abstract

The majority of clinically significant thyroid nodules are less functional than the normal parenchyma and are relatively independent of TSH (thyroid stimulating hormone). These nodules may be divided into 4 classes on the basis of their scintigram appearance, each class with its own diagnostic significance. Nodules of 2 cm or over which do not appreciably displace or replace the normal thyroid scintigram or which produce funtion equal to it are usually benign. The diagnosis of the surgical thyroid nodule may be questioned by the sointigram, supported by the scintigram, but not made by the scintigram. Although benign scintigram patterns which exclude the 70 cancers found have been described, it is entirely probable that malignant lesions will be encountered that do not fit this arbitrary classification. This emphasizes the necessity for considering all available information in determining the need for thyroid surgery.