What Is An Ultrasound?

Ultrasound is a procedure that uses high-frequency sound waves to view internal organs and produce images of the human body. The human ear cannot hear the sound waves used in an ultrasound. Ultrasound is:

The technical term for ultrasound imaging is sonography. 

Ultrasound technology was originally developed as sonar to track submarines during World War I. It was first used medically in the 1950s and is considered very safe. 

The original ultrasound scanners produced still images, but modern scanners produce moving pictures, which are easier to interpret.


How Do You Prepare For An Ultrasound Scan?

No special preparation is required for a routine ultrasound. Wear loose comfortable clothing to your ultrasound appointment.

For a liver or gallbladder scan, the patient is usually asked to fast (take nothing by mouth) for several hours before the test.

For a scan in early pregnancy, the woman is usually asked to drink several glasses of water and not to pass urine for a few hours before the test. A full bladder helps to improve the view of the uterus by displacing nearby loops of intestine.


What Happens During An Ultrasound Procedure?

You will probably be asked to lie down on a bed or table for the scan. Clothing over the area to be scanned is removed, and a special warm oil or gel is applied to the skin. This is to achieve good contact as the transducer is passed back and forth. 

Ultrasonic waves are inaudible and cause no sensation, though pressure from the transducer may be uncomfortable. The scan usually takes 15 to 45 minutes. During the procedure, you will probably be able to watch the ultrasound images on the screen attached to the scanner.

When a scan is performed in conjunction with a biopsy, a local anesthetic reduces or eliminates any discomfort.

Normal activities can be resumed immediately after the test.

Ultrasound is very safe and painless, so there is little risk. 

Your ultrasound images will be analyzed by a radiologist, a physician who specializes in ultrasound and other radiology testing. The radiologist will send a signed report which includes an interpretation of the image to your primary physician. You may receive your results right after your scan. If not, you will receive information on the report through your primary care physician. 



Frequently Asked Questions
Here are some frequently asked questions related to ultrasound:

Q: Is an abdominal ultrasound ordered for any condition other than pregnancy?  

A: There are several reasons the doctor requests an abdominal ultrasound. These include:

• Finding the cause of stomach pain
• Looking for stones in the gallbladder or kidney
• Diagnosing enlargement of an abdominal organ
• Pyloric stenosis, one cause for vomiting in babies
• Suspicion of appendicitis
  
  

• Screening for bleeding in the brain
• Signs of infection
• Cranial abnormalities
  
  

• Urinary tract infection
• The cause for blood in the urine
• High blood pressure
• Back or abdominal pain
• Known or suspected kidney stones
• A family history of kidney disease