What is a subcentimeter solid hypoechoic thyroid nodule?

A subcentimeter solid hypoechoic thyroid nodule is a small, solid nodule in the thyroid gland that appears darker than the surrounding tissue on an ultrasound scan. It is typically less than 1 centimeter in diameter. Subcentimeter solid hypoechoic thyroid nodules are often benign, but some can be cancerous. Therefore, it is important to have any thyroid nodules evaluated by a doctor to determine if further testing or treatment is necessary.