Which echo texture is commonly associated with a thyroid adenoma?

Which echo texture is commonly associated with a thyroid adenoma?

• A. Hyperechoic
• B. Hypoechoic
• C. Isoechoic
• D. Anechoic

Answer: (B)

Thyroid nodules are best characterized on ultrasound by how their tissue reflects sound. An adenoma tends to be a solid, cellular lesion, which makes it appear darker than the surrounding normal thyroid tissue—that is, hypoechoic. The density of the adenoma and its capsule can reduce internal echoes relative to normal parenchyma, so it contrasts as a darker area on gray-scale imaging and may show a thin capsule or halo around it. This hypoechoic texture helps distinguish a solid adenoma from a cyst, which would be completely anechoic, and from nodules that blend in with the thyroid and are isoechoic. Hyperechoic nodules exist but are less typical for adenomas.

Thyroid nodules are best characterized on ultrasound by how their tissue reflects sound. An adenoma tends to be a solid, cellular lesion, which makes it appear darker than the surrounding normal thyroid tissue—that is, hypoechoic. The density of the adenoma and its capsule can reduce internal echoes relative to normal parenchyma, so it contrasts as a darker area on gray-scale imaging and may show a thin capsule or halo around it. This hypoechoic texture helps distinguish a solid adenoma from a cyst, which would be completely anechoic, and from nodules that blend in with the thyroid and are isoechoic. Hyperechoic nodules exist but are less typical for adenomas.