[Morphologic imaging of thyroid carcinoma]

Ultrasonography (US) is the choice morphological imaging modality in the study of thyroid carcinomas. The present technological evolution (high frequency probes, development of Colour-Doppler) allows the detection of small non-palpable nodules, being able to define, in a high percentage of cases, features pointing to the malignant character of a thyroid mass, although the definite assessment of malignancy (invasion of adjacent structures, metastatic cervical nodes) is quite rare. From a diagnostic viewpoint US is required to identify nodules with suspect features, to be submitted to fine needle aspiration biopsy. Moreover, US plays a basic role in the staging--at the cervical level--of carcinomas as well as in the post-operative follow-up. The other imaging modalities (Computed Tomography, Magnetic Resonance Imaging) play a limited role in both staging and post-operative follow-up.