Fig. 1.

US images show the three sonographic patterns. (a) Left thyroid cyst, classified as ATA benign, BTA U2 and TIRADS 3, was shown to be a haemorrhagic cyst on histology. (b) Left thyroid solid and hypoechoic nodule, classified as ATA intermediate suspicion, BTA U4 and TIRADS 4B, was shown to be a benign nodular goitre on histology. (c) Right thyroid solid, hypoechoic nodule with taller-than-wide shape, irregular margins and microcalcifications, classified as ATA high suspicion, BTA U5 and TIRADS 5, was shown to be papillary thyroid cancer on histology. ATA: American Thyroid Association Management Guidelines; BTA: British Thyroid Association Guidelines for the Management of Thyroid Cancer; TIRADS: Thyroid Imaging Reporting and Data System