Ultrasound of the thyroid

Ultrasound has become the investigation of choice for patients with palpable thyroid gland abnormalities because of its high anatomical resolution, wide availability, low cost and lack of radiation exposure. This article reviews the indications for thyroid ultrasound, examination techniques and the sonographic features of both benign and malignant thyroid pathology. Particular emphasis is placed on the role of ultrasound, in combination with fine needle aspiration cytology (FNAC), in evaluating thyroid nodules for malignancy.