Diagnostic imaging in head and neck disease: current applications of ultrasound.

Diagnostic ultrasound has become firmly established as a key imaging modality in obstetrics and gynecology. Its role in abdominal and retroperitoneal disease is also well known and continues to expand. Although usage of ultrasound in the head and neck had its beginnings many years ago, the advent of newer high-resolution transducers has allowed for further investigation of diseases in this area. Of particular interest are the thyroid gland and the extracranial carotid arteries. This review summarizes the current utility of gray-scale and real-time ultrasound in evaluating head and neck disease, and discusses potential future applications of the modality.