Before you get to know how Ultrasound works you need to know what Ultrasound is.
It is a technique or procedure that employs the use of high frequency sound waves for viewing the internal parts of the human body and taking pictures of them. The technique of ultrasound was originally used in World War-I as SONAR technique to locate enemy submarines under the water.
An ultrasound machine works when sound waves from a transducer machine are emitted towards an object. Then those sound waves after striking the object returns back an echo which is then captured by the same device. In this way you can find the shape and distance of that object from the device. The basic principle behind the working of an ultrasound machine is same whatever its application may be. The steps followed are:
When used for medical purposes an ultrasound machine is used to study and take pictures of a particular organ or body part. An ultrasound machine is basically a transducer which is kept over the target body part. This device then emits sound waves which when strike the internal organs give back echoes which are captured by the device.
An echo is created when the sound waves encounter two organs or tissues at different distance. Therefore, they sound differently because of that. Some of the sound is captured back by the device. When sounds from different sources come together it creates an echo.
These captured echoes do not give any information as such. They need to be converted into some other easily understandable medium. Therefore, they are then analyzed by the transducer machine and converted into either still images or moving pictures of the organs being studied. Ultrasound technique has been successfully used by doctors to examine various parts of human body.
Ultrasound waves cannot pass easily through hard substances. Therefore it is mostly used to examine liquid filled organs of the body. For example, liver, gallbladder and the female uterus in case of pregnancy. Although it is not very successful while examining hard tissues or tissues surrounding air or gas.
The best thing about ultrasound technique is that it is a non invasive procedure. Therefore it is completely painless and hassle free. Also this procedure is free from radiation. Therefore, it has almost nil side effects. Another great advantage is that it is very cheap and readily available in all the countries.
We hope the above mentioned information has helped you understand how ultrasound works.

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