Head and Neck Imaging

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multiplicity is not a sign of a benign condition US guidelines for thyroid nodules:
• 80% of nodular disease is due to hyperplasia
(pathologically they are referred to as hyperplastic,
adenomatous, or colloid nodules).
• Malignant and benign nodules present simultaneously
in 10%-20% of cases; thus multiplicity
is not a sign of a benign condition.
• Nodules with large cystic components are
usually benign; however, 20% of papillary
cancers are cystic.
• Comet-tail artifacts are seen in colloid cysts.

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