Fetal Hydrocephalus

Fetal hydrocephalus is a congenital finding that affects the brain. The contents of the brain consist primarily of the brain tissue, blood and cerebrospinal fluid (CSF). Fetal hydrocephalus is the buildup of CSF in the ventricular system of the brain, which results from a lack of absorption, blockage of flow or overproduction of CSF. It may potentially cause increased pressure in the head and an expansion of the skull bones. Hydrocephalus occurs in approximately 1 in every 1000 births.

How Is Fetal Hydrocephalus Diagnosed?

Hydrocephalus can be detected through ultrasound (sonogram). Evaluation of the brain and cranial structure is part of the routine ultrasound examination done by many obstetricians as part of their prenatal care. However, sometimes hydrocephalus may not develop until the third trimester, and therefore, may not be diagnosed until the end of the pregnancy.

If it is detected on ultrasound, the patient may undergo a fetal brain MRI (magnetic resonance imaging) to determine the severity of the finding.

How Is Fetal Hydrocephalus Treated?

If a baby is diagnosed with fetal hydrocephalus before he is born, the surgeons and nurses at Lurie Children’s spend time counseling parents about what to expect when their baby is born. Patients will receive both pre-natal and post-natal evaluation by neurosurgeons and neurologists. As soon as the baby is born, parents should bring their child in for a detailed examination. A physical examination is performed, and measurements of the infant's skull are taken.

Treatment depends on the type of hydrocephalus and can range from medical management to procedures that draw out the extra CSF. One type of surgery involves placing a shunt, or tube, into the child's head to drain the CSF and redirect the additional fluid to another part of the body to be absorbed. The other type of surgery that may be performed is called endoscopic third ventriculostomy (ETV). In this procedure, the neurosurgeon creates a small hole in the bottom of one of the ventricles (or spaces in the brain) causing the CSF to bypass the obstruction and flow into the natural pathways.

What Is the Long-term Outlook for Fetal Hydrocephalus?

The long-term outlook for a child born with hydrocephalus depends greatly on the severity of the problem and the presence of other associated abnormalities. Hydrocephalus can affect the brain and a child's development to varying degrees.

It is recommended that these children receive follow-up care and evaluations to prevent infection and monitor the ongoing functionality of the shunt.