An ultrasound is a procedure that uses high frequency sound waves, called ultrasonic waves, to produce images of internal organs and the interior of the body. This form of imaging works largely in the same way as sonar. These images are often used in obstetrics but have non-obstetric uses including biopsies and echocardiographs. They can be used to produce either a still or moving image.
Sound waves traveling through different objects is integral to producing an ultrasound image. An ultrasonic sensor called the transducer targets the organ or area of the body being scanned, emitting ultrasonic waves. An echo is produced when the sound waves hit different tissue. The transducer detects the echo and feeds the data into a computer. The computer will then transform the sound into images.
In order for the transducer to easily move over the skin, a gel is applied. This gel also helps to allow the transducer as close to the skin as possible. A slight pressure may be felt if the area is tender due to inflammation. The transducer may also be inserted into the body for an exam. Mild anesthesia is often used for internal exams.
There are no limitations to activity after the ultrasound. The image is then interpreted by a trained professional or radiologist who may then give the patient his or her results. Often, results are passed along to the patient's general practitioner.
Ultrasounds do not have any side effects, since radiation is not used. It is a relatively easy and low cost procedure. These also produce real time images and can be used to help guide invasive procedures. The main concern with ultrasound is that it does not easily distinguish between air and bone and is not good for imaging bones or the lungs.
An ultrasound is commonly used to produce a sonogram or picture of a baby in the uterus. The image may be used to determine the size of the baby, reveal multiple babies, identify some abnormalities and diseases, and is necessary for amniocentesis. Other conditions that can be detected using this procedure include early fetal death, an impending miscarriage, and placenta position. This procedure is used after a woman is 16 weeks pregnant.
Other non-obstetric uses are used to examine internal organs. Tumors, swelling and cysts can all be examined using these high frequency waves. An echocardiograph is a special type of ultrasound used to investigate the heart. This is a diagnostic procedure that looks at structural abnormalities and blood flow though valves.