How Ultrasound works


Ultrasound, also called sonography, uses sound waves to develop ultrasound images of what's going on inside the body. An instrument called a transducer emits high-frequency sound, inaudible to human ears, and then records the echoes as the sound waves bounce back to determine the size, shape, and consistency of soft tissues and organs.


It is used to help diagnose the causes of pain, swelling and infection in the body’s internal organs and to examine a baby in pregnant women and the brain and hips in infants. It’s also used to help guide biopsies, diagnose heart conditions, and assess damage after a heart attack. Ultrasound is safe, noninvasive, and does not use ionizing radiation.



Uses of Ultrasound Tests


Ultrasound imaging has many uses in medicine, from confirming and dating a pregnancy to diagnosing certain conditions and guiding doctors through precise medical procedures.


Ultrasound is used to help physicians evaluate symptoms such as:

  • pain

  • swelling

  • infection

Ultrasound is a useful way of examining many of the body's internal organs, including but not limited to the:

  • heart and blood vessels, including the abdominal aorta and its major branches

  • liver

  • gallbladder

  • spleen

  • pancreas

  • kidneys

  • bladder

  • uterus, ovaries, and unborn child (fetus) in pregnant patients

  • eyes

  • thyroid and parathyroid glands

  • scrotum (testicles)

  • brain in infants

  • hips in infants

  • spine in infants


Ultrasound is also used to:

  • guide procedures such as needle biopsies, in which needles are used to sample cells from an abnormal area for laboratory testing.

  • image the breasts and guide biopsy of breast cancer

  • diagnose a variety of heart conditions, including valve problems and congestive heart failure, and to assess damage after a heart attack. Ultrasound of the heart is commonly called an “echocardiogram” or “echo” for short.


Types of Ultrasound

Transvaginal ultrasound - a transducer wand is placed in a woman’s vagina to get better images of her uterus and ovaries.

Transrectal ultrasound - sometimes used in the diagnosis of prostate conditions

Transesophageal echocardiogram - uses the transducer probe in the esophagus so that the sonographer can obtain clearer images of the heart


Ultrasound technology has also advanced to allow for different types of imaging like:

  • Doppler is a special type of ultrasound that creates images of blood flow through vessels.

  • Bone sonography helps doctors diagnose osteoporosis.

  • Echocardiograms are used to view the heart.

  • 3D imaging adds another dimension to the ultrasound image, creating three-dimensional interpretations rather than the flat two-dimensional images that are made with traditional ultrasound.

  • 4D ultrasounds show 3D images in motion.


Benefits of Ultrasound

  • Most ultrasound scanning is noninvasive (no needles or injections).

  • Occasionally, an ultrasound exam may be temporarily uncomfortable, but it should not be painful.

  • Ultrasound is widely available, easy-to-use and less expensive than other imaging methods.

  • Ultrasound imaging is extremely safe and does not use any ionizing radiation.

  • Ultrasound scanning gives a clear picture of soft tissues that do not show up well on x-ray images.

  • Ultrasound is the preferred imaging modality for the diagnosis and monitoring of pregnant women and their unborn babies.

  • Ultrasound provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as needle biopsies and fluid aspiration.



A typical ultrasound takes between 30 minutes and an hour. Ultrasounds usually are not uncomfortable, and patients are awake and alert during the procedure. Often a technician will discuss what he or she is seeing during the test, but in some instances, the patient may need to wait to discuss the findings with their doctor.






 Published at: 11/07/2016