Thyroid Nodule Imaging, Status and Limitations

Thyroid nodules Thyroid nodules are common, occurring in almost two-thirds of some populations; among these only about 7% are malignant (1). The most important question with any new discovered thyroid nodule is, “is this malignant?” The main arbiter of malignancy or benignity remains fine needle aspiration. Given the resources involved, doing a fine needle aspiration cytology (FNAC) in every discovered nodule would be prohibitive to impossible. The clinician must decide which nodule to investigate and which to watch in the hope that this will never turn out to be malignant. FNACs are used basically to decide which nodule to operate upon (or more importantly which to not operate upon) and clinical and imaging features are used to decide which nodule to investigate by FNAC and which to leave alone. This paper describes the various imaging options for looking at thyroid nodules and briefly discusses the advantages and disadvantages with each.