What is an Ultrasound Doppler? June 27 2014
The Ultrasound test has become popular testing in recent years. From a soon to be mother seeing the smile on her unborn child for the first time, to the early detection of cysts in the abdominal area or heart disease in the pulmonary area, most people will have an ultrasound at some time in their live. The actual technology behind an ultrasound is fascinating. By utilizing an ultra high frequency of sound that is well above the range of human hearing, care providers are able to view the inside the patient in a non-invasive manner.
To do this, Ultra high frequency sound waves are emitted from a Doppler probe that is in direct contact with the patient’s body. Inside the patient, these waves reflect off of structures in the body dependent on the frequency of the sound. The Ultrasound device then receives these reflections and created a picture of what it is “looking” at, which is then displayed on an external screen. Among the variety of Ultrasound testing devices, the Ultrasound Doppler has become very popular piece of healthcare equipment. Dopplers utilize a principle called the “Doppler Effect”, or the change in frequency as an object moves towards or away from an observer. As the object moves closer to the observer, the amount of time between the approaching sound waves gets smaller and smaller, increasing the frequency. Similarly, as the object moves away, the amount of time increases, decreasing the frequency. A way to understand exactly what the Doppler effect is to think about how a siren sounds as an emergency vehicle zips past you. This process is very similar to a bat that cannot see visually but uses such sound waves to detect objects when hunting or flying.
Using this principle, a Doppler can create a moving picture of blood in a blood vessel. Very recently, special Dopplers that perform an Ankle-Brachial Index Test, or ABI test, have become very popular in the early diagnosis of Peripheral Arterial Disease, or PAD. There are many uses for a Doppler and is a must have for any physician office or clinic.