Ultrasound is a medical procedure that uses sound waves to "see" inside the body. It is used for:

• Examination

For example, healthcare professionals can use ultrasound to study the heart or to help check the health of an unborn baby.

• Diagnosis

Ultrasound can help diagnose many medical conditions, such as cancer, gallbladder disease, blood clots and eye disorders.

How Ultrasound Works
Ultrasound uses sound wave frequencies too high to be heard by humans. Here's how it works:

• A transducer-a small, microphone-like device is placed over the area being examined.
• Sound waves pass harmlessly through the skin from the transducer. The sound waves bounce off certain organs and tissues in the body. This creates "echoes".
• The echoes are reflected back through the transducer.
• A television monitor shows images as the transducer converts the echoes to electrical signals. These moving images may be viewed immediately and recorded or photographed for further study.

A Useful Tool
Ultrasound can help detect, diagnose or monitor:

• Heart Problems
  Ultrasound exams can make it possible to detect clots within the heart, evaluate damage after a heart attack, diagnose heart defects, an enlarged heart and heart and artery diseases.
• Abdominal Disorders
  For example, ultrasound may be used to detect gallstones, check for problems in the liver, kidneys, pancreas or spleen or monitor the success of a kidney transplant.
• Blood Vessel Problems
  Ultrasound exams may show problems such as enlargements in vessels that could burst and cause internal bleeding or a narrowing of the main artery leading to the brain, which could lead to stroke.
• Cancer
  For example, ultrasound can locate lumps in organs or tissues and can often show the difference between fluid-filled cysts and cancerous tumors. It can also guide needle biopsy (removal of tissue using a needle instead of surgery) or help detect prostate cancer and monitor treatment.
• Pelvic Disorders
  Ultrasound can help determine the cause of pain or bleeding in women's reproductive organs.
• Other Problems
  It may be used when imaging the breasts, examining the thyroid gland in the neck or inserting a needle to obtain fluid from the lungs.