What is ultrasonography?

In ultrasonography, or ultrasound, high-frequency sound waves, inaudible to the human ear (can’t be heard), are sent through body tissues. The echoes are recorded and converted into video or photographs.

Ultrasound images help diagnose a wide range of diseases and conditions. The idea for ultrasonography came from sonar technology, which uses sound waves to find underwater objects.

Ultrasound is used to create images of soft tissue structures, such as the gall bladder, liver, heart, kidney, female reproductive organs--even of babies in the womb. Ultrasound can also detect blockages in the blood vessels.

Ultrasound cannot be used to produce images of bones because they are too dense to penetrate. In addition, the intestinal tract and normal lung tissue are not easily identified with ultrasound because air or gas can interfere with the production of ultrasound images.

Ultrasound may be used by itself or with other diagnostic procedures.

What is examined during a renal ultrasound?

During a renal ultrasound, the kidneys are examined to determine their size, shape, and exact position.

What is examined during a renal/pelvic ultrasound?

During a renal/pelvic ultrasound, the kidneys are examined to determine their size, shape and exact position. The bladder may be evaluated to help determine the cause of unexplained blood in the urine or difficulty in urinating, or to look for bladder stones.

Before the renal or pelvic ultrasound

You do not have to fast for this test, but your bladder must be full. See instructions below.

  • Finish drinking one quart (32 oz.) of fluids one hour before your scheduled test. Once you start drinking, do not empty your bladder until the exam is completed.
  • Failure to follow the above preparation will result in delays or possible cancellation of your examination.
On the day of the test

Please do not bring valuables such as jewelry and credit cards.

  • It is very important to arrive for the test with a full bladder. This allows the technologists and radiologist to view the bladder while it is full and after it has been emptied.
  • Your ultrasound test is performed by registered, specially trained technologists, and interpreted by a board-certified radiologist.
  • You may be asked to change into a hospital gown.
During the test
  • You will lie on a padded examining table.
  • A warm, water-soluble gel is applied to the skin over the area to be examined. The gel does not harm your skin or stain your clothes.
  • A probe is gently applied against the skin. You may be asked to hold your breath briefly several times.

There is almost no discomfort during the test. Because you need to have a full bladder for the test, you may feel some discomfort when the probe is applied over the bladder area.

The ultrasound takes about 40 minutes to complete.

After the test

The gel will be wiped off your skin. Your physician will discuss the test results with you when the results become available.

Are there any side effects from an ultrasound test?

Studies have shown that ultrasound is not hazardous. There are no harmful side effects. In addition, ultrasound does not use radiation, as X-ray tests do.

References

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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 2/17/2017...#4997