Thyroid ultrasound …. CFD
06.05.2011 08:08
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thought that this may occur following haemorrhage and all fibrosis within a nodule. The distinction that needs to be made is from the fine punctate calcification of papillary carcinoma and the punctate or slightly more globular calcification that is seen in medullary carcinoma of the thyroid. Figure 11
Patterns of calcifications in a thyroid nodule. A. Typical benign calcification – peripheral/ “egg shell”. B. Solid hypoechoic lesion containing micro-calcification – diagnosis – papillary carcinoma
a
b
Echogenicity The majority of benign thyroid nodules will be iso-or hyper -echoic relative to the normal "background" echotexture of the thyroid. If a solid thyroid lesion is hyper echoic relative to normal thyroid tissue, the incidence of malignancy is quoted as only 4%. If the lesion is isoechoic the incidence of malignancy increases to 26% whereas malignancy is said to occur in 63% of hypo- echoic nodules. A significantly hypoechoic solid lesion should always be viewed with suspicion, the presence of an irregular margin, punctate calcification within or intra-nodular colour flow are additional features that indicate malignancy.