Syrinx (medicine) facts for kids

A syrinx is like a small, fluid-filled pocket that can form inside your spinal cord or brain stem. It's a rare condition. When this pocket forms in the spinal cord, it's called syringomyelia. If it appears in the brain stem, it's known as syringobulbia. Sometimes, a syrinx can even affect the nerves in the elbow.

What is a Syrinx?

The spinal cord is a long, important bundle of nerves that runs down your back. It connects your brain to the rest of your body. This allows your brain to send messages to your muscles and receive information about touch, pain, and temperature. A syrinx is a cavity, or space, that fills with fluid within this vital spinal cord or brain stem.

How Does a Syrinx Affect the Body?

The symptoms of a syrinx usually start slowly. They often appear between the ages of 12 and 45. The specific problems depend on where the syrinx is located and how large it has become.

Symptoms in the Spinal Cord (Syringomyelia)

When a syrinx forms in the spinal cord, it can cause several issues.

• You might have trouble feeling pain or changes in temperature. For example, you might not notice a burn or cut on your hand right away.
• Weakness can develop in your hands and arms.
• Your muscles might shrink (atrophy).
• You could feel stiffness in your back, shoulders, arms, or legs.
• Some people experience headaches.
• These symptoms can sometimes affect one side of the body more than the other.

Symptoms in the Brain Stem (Syringobulbia)

A syrinx in the brain stem is much rarer. The brain stem controls many basic body functions.

• You might feel dizzy (this is called vertigo).
• Your eyes might make uncontrolled, jerky movements (called nystagmus).
• It can cause weakness in your face or tongue.
• Speaking clearly (dysarthria) or swallowing food (dysphagia) might become difficult.
• Your voice could sound hoarse.

What Causes a Syrinx to Form?

A syrinx forms when the normal flow of a special fluid around your brain and spinal cord gets blocked. This blockage causes the fluid to collect inside the spinal cord itself.

The Role of Cerebrospinal Fluid

Your brain and spinal cord are surrounded by a clear, watery substance called cerebrospinal fluid (CSF). Think of it as a protective cushion. CSF also carries nutrients to your brain and spinal cord and removes waste. Normally, CSF flows freely around these areas. If something blocks this flow, the fluid can get trapped. It then collects in a small area of the spinal cord, forming a syrinx. The fluid inside the syrinx can move around due to pressure changes. Doctors believe this constant movement can make the syrinx grow larger. As it grows, it can damage the delicate nerves in the spinal cord.

Common Causes and Conditions

Many different medical conditions can lead to a syrinx.

• Often, syrinxes are linked to problems with how the brain or spinal cord developed before birth.
• One common cause is a Chiari malformation. This is when part of the brain pushes down into the spinal canal.
• Other causes include spinal cord tumors.
• Scar tissue from a past spinal injury can also block CSF flow.
• Sometimes, a syrinx can form without any clear reason.
• These conditions can cause the syrinx to expand. This often happens during the teenage years or early adulthood. About 30% of people with a spinal cord tumor eventually develop a syrinx.

How is a Syrinx Discovered?

Doctors might suspect a syrinx if someone has symptoms like those described above. Especially if they have trouble feeling pain or temperature in a specific pattern. To confirm a syrinx, doctors use a special imaging test. This test is called an MRI (Magnetic Resonance Imaging). An MRI takes detailed pictures of the entire spinal cord and brain. Sometimes, a special dye called Gadolinium is injected. This helps doctors see if there is a tumor connected to the syrinx.

How is a Syrinx Treated?

The main goal of treatment is to address the underlying problem causing the syrinx.

• If there's a Chiari malformation or a spinal cord tumor, doctors will try to correct it.
• Surgery is often performed to relieve pressure around the brain and upper spinal cord. This is called surgical decompression.
• While surgery can help stop the syrinx from growing and prevent further damage, it usually cannot reverse severe nerve damage that has already occurred.

Where Does the Word "Syrinx" Come From?

The word syrinx comes directly from an ancient Greek word. This Greek word meant "tube." You might recognize this root in another word: "syringe."