Computed tomography of the thyroid ,88 and and9).9). CT scans are also the most sensitive diagnostic tool for the detection of pulmonary micro-metastases. Many of the neck US features that are considered as suggestive signs of disease recurrence are also applicable to CT examination. These signs might include sizable rounded nodules in the thyroid bed, fine calcifications, or cystic change. In cases of elevated thyroglobulin with negative neck US and iodine whole body scintigraphy (WBS), fluorodeoxyglucose (FDG) positron emission tomography (PET) is the next modality of choice. Dedifferentiated thyroid carcinoma usually has avid FDG-PET uptake and a negative radioiodine scan, typically does not respond to
Computed tomography of the thyroid high thyroglobulin content is iso-dense to muscle. Thyroid nodules that are detected by an imaging study but have not been previously detected or suspected clinically are considered to be ITNs. ITNs are one of the most common incidental findings on neck imaging. ITNs are reported in up to 25 % of chest CT scans, and in 16–18 % of cervical region cross-sectional imaging, including CT and MRI scans. The rate of malignancy in the detected ITNs on CT and MRI scans varies from 0 % to 11 %. Incidentally detected thyroid carcinomas are more likely to be papillary thyroid carcinomas