Computed tomography of the thyroid attenuation (80–100 Hounsfield Units). The presence of thyroiditis can be suggested by a diffusely enlarged and hypo-attenuating (around 45 Hounsfield Units) thyroid gland. This is probably due to follicular cell destruction and reduced thyroid iodine concentration. Marked homogenous enhancement is typically expected. Therefore, moderate thyroid enhancement in a case of thyroiditis suggests a diffuse inflammatory process. It is essential to clinically correlate this with a thyroid function test and serum autoantibody levels. During embryogenesis, the bi-lobed thyroid migrates inferiorly from the foramen cecum of the tongue to the lower neck. Initially, the thyroid primordium passes anterior to the primordial hyoid
Computed tomography of the thyroid stage is classified by site: N1a indicates level VI nodal involvement, including paratracheal nodes; N1b indicates unilateral or bilateral lateral cervical nodal disease or superior mediastinal nodal disease (Figs. 4, ,55 and and6)6). The incidence of hematogenous spread of follicular carcinomas is 21–33 % and that of PTCs is 2–14 %. In medullary thyroid cancer and anaplastic thyroid cancer, distant metastasis was reported in 25 % and 40 % of patients, respectively. Distant metastases from DTCs tend to have a more favourable prognosis. Distant metastatic disease may appear years after the initial presentation. Therefore, imaging for distant metastases is usually