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Cranial Ultrasound

How To Prepare

No special preparation is required before having this test.

If an older baby is having the test, it may help to have the baby be a little hungry. The baby can be fed during the test, which will help the baby to be comforted and to hold still during the test.

How It Is Done

This test is done by a doctor who specializes in interpreting imaging tests (radiologist) or by an ultrasound technologist (sonographer) who is supervised by a radiologist. For a baby, cranial ultrasound may be done at your baby's bedside in the neonatal intensive care unit (NICU). With the baby lying on his or her back, the transducer is moved across the soft spot (fontanelle) on top of the head. You may be asked to hold your baby during the test. Pictures of the brain and inner fluid chambers (ventricles) can be seen on a video monitor.

For an adult, cranial ultrasound is done during brain surgery to help find a brain mass.

A cranial ultrasound usually takes 15 to 30 minutes.

How It Feels

There is usually no discomfort involved with having a cranial ultrasound test. Unless the gel is first warmed to body temperature, it may feel cold when it is put on the skin.


There are no known risks linked with a cranial ultrasound test.


Cranial ultrasound uses reflected sound waves to produce pictures of the brain and the inner fluid chambers (ventricles) through which cerebrospinal fluid (CSF) flows.

Cranial ultrasound


The size and shape of the brain appear normal.

The size of the brain's inner fluid chambers (ventricles) is normal.

Brain tissue appears normal. No bleeding, suspicious areas (lesions), abnormal growths, or evidence of infection are present.


Bleeding in the brain may be present, which may indicate intraventricular hemorrhage (IVH). Repeated tests are often done to check the bleeding or to look for problems caused by the bleeding.

Suspicious areas or lesions around the brain's ventricles may be present. This may be a sign of periventricular leukomalacia (PVL), a condition in which the brain tissue around the ventricles is damaged.

The brain and ventricles may be enlarged from the buildup of excessive amounts of cerebrospinal fluid (CSF). This may point to hydrocephalus.

Abnormal growths may be present, which may point to a tumor or cyst.

Suspicious findings may be present, which may point to encephalitis or meningitis.

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

  • The baby does not remain still during the test.
  • Having an open wound or recent surgical wound in the area being viewed.

WebMD Medical Reference from Healthwise

Last Updated: November 29, 2012
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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