Hydrocephalus: Tests and Diagnosis

What tests are used to diagnose hydrocephalus?

If hydrocephalus is expected based on your child’s history and symptoms, a brain imaging test must be done to determine if the fluid spaces inside the brain are enlarged.

In infants, a cranial ultrasound can be done to assess the fluid spaces. An ultrasound uses sound waves to look at structures inside the body. This study can only be done in infants with an open anterior fontanel (also known as a “soft spot”). It can identify whether or not hydrocephalus is present, but is often not sensitive enough to help determine the cause. Often a CT scan or MRI will also be necessary if hydrocephalus is present.

A CT, or CAT scan, stands for computed tomography. X-ray technology is used and manipulated to produce images of the brain. A CT scan is much more sensitive than ultrasound and can not only identify that hydrocephalus is present, but it can also help identify potential causes such as bleeding or tumors. A CT scan of the head is very quick, lasting just 1 to 2 minutes to obtain the information. Children typically do not need to fast or be sedated for this study.

An MRI (magnetic resonance imaging) uses a very powerful magnet to produce images of the brain. MRI is highly sensitive in identifying hydrocephalus and possible causes. It provides detailed information about the anatomy of the brain. Often, a person with hydrocephalus will undergo MRI imaging when they are diagnosed to help determine the cause. A full brain MRI is a much longer test than a CT, lasting at least 30 minutes, sometimes longer depending on the exact study. For a full MRI, it is important that the child does not move during the study – so many children will require sedation. A full MRI is not always needed to test for hydrocephalus.

Why choose Children’s Hospital Colorado for testing for hydrocephalus?

Children with hydrocephalus often require frequent imaging tests to assess the status of their hydrocephalus treatment. In past years, this meant multiple CT scans. Because each CT scan exposes the child to a small dose of radiation, over a lifetime, those doses of radiation can add up.

Here at Children’s Colorado, we have the ability to do a quick MRI scan that provides all the necessary information in just 2 to 3 minutes. Children do not need sedation and will not get exposed to radiation. This study, called an MRI “shunt series,” is now the main study of choice in assessing patients with hydrocephalus. This special MRI is only available at Children’s Colorado, both on the main and North Campus.

How do doctors diagnosis hydrocephalus?

Children displaying signs of symptoms of hydrocephalus will be seen by a neurosurgery doctor and undergo imaging tests. Your child’s doctor at Children’s Colorado will perform a thorough history and physical exam and will review the brain images from the tests.

The sophisticated neurological exam will show the signs and symptoms of hydrocephalus, and your child’s doctor will look for evidence of pressure on the brain and evaluate the size and anatomy of the ventricles.