What is an ultrasound?

Ultrasound (also known as sonography or ultrasonography) is a diagnostic procedure that transmits high-frequency sound waves, inaudible to the human ear, through body tissues. The echoes are recorded and transformed into video or photographic images of the internal structures of the body.

Ultrasound images help in the diagnosis of a wide range of diseases and conditions. Ultrasound is used to create images of soft tissue structures, such as the gall bladder, liver, heart, kidney, female reproductive organs -- and even of fetuses still in the womb. Ultrasound can also detect blockages in the blood vessels.

Ultrasound may be used with other diagnostic procedures or by itself. Studies have shown that ultrasound is not hazardous. There are no harmful side effects. In addition, ultrasound does not use radiation, as X-ray tests do.

What is a thyroid ultrasound?

A thyroid ultrasound examines the gland that is located centrally in a patient’s lower neck. The test is used to assess the size of the gland and to find out if there are nodules or lesions within the gland.

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