Hyperthyroidism is a condition in which the thyroid gland is overactive, producing excessive amounts of thyroid hormones that speed up the body’s metabolism. On ultrasound, the thyroid in Graves disease, the most common cause of hyperthyroidism, typically appears diffusely enlarged with decreased echogenicity and markedly increased blood flow on color Doppler, a finding described as thyroid inferno. Toxic nodules causing hyperthyroidism appear as focal areas with increased Doppler flow compared to the surrounding thyroid tissue. Ultrasound helps distinguish between the different causes of hyperthyroidism and identifies any associated nodules that may require biopsy to rule out malignancy.
Sonography Term