Hydromyelia in Children

Hydromyelia is a condition that involves an abnormal widening of the center of the spinal cord. The spinal cord is a network of nerve cells and nerve connections that carry messages back and forth between the body and the brain.

As the center of the spinal cord widens, it creates a cavity that fills with the clear fluid that surrounds the brain and the spinal cord (cerebrospinal fluid, or CSF).

As this fluid-filled cavity grows, it puts pressure on the spinal cord and damages the nerve cells and connections. This damage can cause weakness and numbness in the body.

What are the causes?

This condition is caused by a buildup of CSF in the canal that runs down the center of the spinal cord. CSF is a clear fluid that flows through the central nervous system. It cushions and nourishes the spinal cord and the brain. Hydromyelia can result from an abnormal connection between the central canal of the spinal cord and a space in the brain (fourth ventricle). This allows extra CSF to flow into and build up in the spinal canal. The exact reason why this connection develops is not known.

Some children are born with hydromyelia. In infants and children, the condition is associated with:

• A buildup of CSF deep within the brain (hydrocephalus).
• Birth defects, such as:
  • Chiari malformation type 2. This is a condition in which the brain stem and the portion of the brain that controls movement (cerebellum) push down onto the spinal cord area.
  • Dandy-Walker malformation. This is a condition that causes defects in both the cerebellum and the cavity that drains CSF from the brain to the spinal cord (fourth ventricle). The defects cause poor drainage of CSF in the brain.

What are the signs or symptoms?

Minor hydromyelia does not cause symptoms. If the widening of the spinal cord increases, symptoms may develop gradually over time. They may vary, depending on where the widening is in your child’s spinal cord. Symptoms may include:

• Increase in head size in infants.
• Bulging of the soft spot (fontanel) on a baby’s head.
• Weakness in the arms and hands.
• Loss of feeling in the neck and hands.
• Neck and shoulder pain.
• Headaches.
• Leg stiffness.
• Curved back (scoliosis).
• Poor bladder control.
• Difficulty walking.

How is this diagnosed?

This condition may be diagnosed based on:

• Your child’s symptoms and medical history.
• A physical exam.
• An MRI of the spinal cord.

How is this treated?

Treatment for this condition depends on your child’s symptoms and the severity of the condition.

• In minor cases of hydromyelia, where there are mild symptoms or no symptoms at all, your child may not need to be treated. Some hydromyelia symptoms may go away over time. Your child’s health care provider will monitor your child’s condition carefully. This may include monitoring with repeated MRIs.
• In major cases of hydromyelia, or if symptoms get worse, your child may need surgery. This may include:
  • Placing a flexible tube (shunt) in the brain or spinal cord to drain the fluid into another part of the body.
  • Removing small pieces of bone in the spine (laminectomy) to reduce pressure on nerves and the spinal cord.

Follow these instructions at home:

• Follow all instructions given by your child’s health care provider.
• Watch your child’s condition for any changes.
• Keep all follow-up visits as told by your child’s health care provider. This is important.

Contact a health care provider if:

• Your child’s symptoms get worse.
• Your child has new symptoms.
• You do not have enough support at home.

Get help right away if your child:

• Has a seizure.
• Has a severe headache or stiff neck.
• Loses the ability to move.

Summary

• Hydromyelia is a condition in which there is an abnormal widening of the center of the spinal cord. As it widens, it creates a cavity that fills with cerebrospinal fluid (CSF). This puts pressure on the spinal cord and damages the nerve cells and connections.
• Minor hydromyelia does not cause symptoms. Symptoms may develop gradually over time if the widening of the spinal cord increases. They may include numbness, weakness, or pain.
• Treatment depends on your child’s symptoms and how severe the condition is. Minor cases may be monitored with repeated MRI. Major cases of this condition may require surgery.