Fetal Ventriculomegaly
Condition
(Ventriculomegaly)
Definition
Fetal ventriculomegaly is the widening of the fluid-filled spaces of the brain. These are called the ventricles. It happens in babies before they are born.
Causes
Fetal ventriculomegaly may be caused by problems with how the brain grows. It may also be caused by the flow of cerebrospinal fluid (CSF). This fluid surrounds and cushions the brain and spinal cord. It should move smoothly. If its flow is slowed or stopped, it can put pressure on the ventricles and make them get bigger.
Risk Factors
Things that may raise the risk of fetal ventriculomegaly are:
- Brain cysts
- Spina bifida
- Bleeding within the brain
- A rare birth defect called agenesis of the corpus callosum
Certain infections in the mother can raise the risk. These are:
- Cytomegalovirus—an infection caused by a type of herpes virus
- Toxoplasmosis—an infection linked to cat stool or infected food
- Syphilis—a sexually transmitted infection (STI)
- Chickenpox
- Lymphocytic choriomeningitis—a virus spread by mice (rare)
Symptoms
After birth, a child may have:
- Rapid head growth
- A bulging soft spot
- Scalp veins that bulge
- Problems with eye movement
- Delays in development
- Problems feeding
- Vomiting
- Fussiness or sleepiness
Diagnosis
Fetal ventriculomegaly is often found during an ultrasound before the baby is born. More testing may be done by specialists and after birth.
Before birth, the baby’s health may be checked with:
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Treatment
Sometimes fetal ventriculomegaly gets better on its own. The baby's health will be monitored.
If the problem gets worse, other methods will be needed to drain the fluid. This can be done by placing a ventriculoperitoneal shunt after the child is born.
Prevention
There are no known guidelines to prevent fetal ventriculomegaly.
American College of Obstetrics and Gynecology
Women’s Health—US Department of Health and Human Services
CANADIAN RESOURCES:
Health Canada
The Society of Obstetricians and Gynaecologists of Canada
American College of Obstetrics and Gynecology
Women’s Health—US Department of Health and Human Services
CANADIAN RESOURCES:
Health Canada
The Society of Obstetricians and Gynaecologists of Canada
References
- Hydrocephalus in children. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/hydrocephalus-in-children.
- Pediatric ventriculomegaly. Children’s National Health System website. Available at: http://childrensnational.org/choose-childrens/conditions-and-treatments/fetal-carepregnancy/ventriculomegaly.
- Ventriculomegaly and hydrocephaly. Children’s Memorial Hermann Hospital website. Available at: http://childrens.memorialhermann.org/conditions/ventriculomegaly-and-hydrocephaly.
- Wright Z, Larrew TW, et al. Pediatric Hydrocephalus: Current State of Diagnosis and Treatment. Pediatr Rev. 2016 Nov;37(11):478-490.
Contributors
- Kari Kuenn, MD
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