What is the abducens nerve?

The abducens nerve, also known as the sixth cranial nerve (CN VI), is a nerve that controls the movement of the lateral rectus muscle of the eye. This muscle moves your eye to the outside, meaning it moves your left eye to the left and your right eye to the right.

The abducens nerve is a type of extraocular nerve, which is a nerve that’s outside of your eye. Your nerves help your brain communicate with your muscles. Your abducens nerve works with your oculomotor nerve (third cranial nerve or CN III) and your trochlear nerve (fourth cranial nerve or CN IV) to move the muscles around your eye.

Nerves help you feel sensations (sensory function) and move your muscles (motor function). This nerve doesn’t have any sensory functions. Instead, it only has a motor function.

What’s the function of the abducens nerve?

The abducens nerve tells your lateral rectus muscle to move your eye to the outside. You have an abducens nerve for both eyes, which moves your right eye to the right and your left eye to the left. This nerve also works with the medial rectus muscle to make both eyes move to the left and right at the same time.

CN VI has an important job to move your eye and help you see the world around you. You’re using this nerve and your lateral rectus muscle now to move your eyes to read this line of text, from left to right.

This nerve and muscle also help you learn more about your surroundings. For example, imagine you’re in a park. You hear a bird chirp from a nearby tree to your right. Your abducens nerve tells your outer eye muscle to move your eyes to the right so you can look at the bird in the tree.

Where is the abducens nerve located?

The abducens nerve is a very small nerve in your head, just behind your eyes. It looks similar to a tree branch.

You have two abducens nerves, one on the left and right side of your eyes. They extend from the tree trunk or your brainstem (the back part of your brain that connects to your spinal cord) and attach to a muscle inside your eye socket. They pass through the subarachnoid space, dura mater and a canal (opening) through your skull into your eye socket where it meets your lateral rectus muscle.

It has the second longest path of travel for a nerve within your brain, after the vagus nerve.

What is the abducens nucleus?

The nucleus of the abducens nerve (abducens nucleus) is the command center of this nerve. It tells your nerve what to do. While this nerve reaches from your brainstem to your eye socket, you can find the nucleus in the pons. The pons are in the upper back portion of your brain. The pons sit below your midbrain and above your medulla oblongata, which is right above your spinal cord.

What is a common condition that affects the abducens nerve?

A common condition that affects CN VI is abducens nerve palsy or sixth nerve palsy. This is nerve damage that weakens the lateral rectus muscle and leads to muscle paralysis.

This can occur due to diabetes, high blood pressure, head injuries, stroke or many other causes. It’s important to see a healthcare provider right away to determine the cause.

Nerve damage is also common because this nerve stretches from the back to the front of your brain. The size of this nerve puts it more at risk of injury.

What are the symptoms of abducens nerve conditions?

If you have abducens nerve palsy, the muscle that allows you to move your eye(s) to the left and right doesn’t get messages from your brain via your nerve to tell it to move. As a result, you may experience the following symptoms:

• Difficulty or inability to move your eye(s) to the left and/or right
• Double vision (diplopia)
• Eye misalignment
• Eye strain or pain

What tests check the health of my abducens nerve?

A healthcare provider or eye care specialist will check the health of CN VI through the following tests:

• Eye examination: Your provider will check your vision and ask you to move your eyes in different directions to see what movements are possible or affected.
• Blood tests: Your provider may offer blood testing to determine the cause of your symptoms.
• Imaging tests: A common imaging test to look at your abducens nerve is a magnetic resonance imaging (MRI) test. An MRI lets your provider see the nerves and tissues inside of your head.

What are treatments for abducens nerve conditions?

After your provider makes a diagnosis and determines the cause of your symptoms, they’ll offer treatment for your affected abducens nerve. Treatment may include:

• Managing or treating the underlying condition that causes symptoms
• Wearing an eye patch or corrective lenses
• Receiving botulinum toxin injections
• Surgery

Your provider will offer treatment that’s specific to your needs based on what’s causing your symptoms. This can vary from person to person.

How do I take care of my abducens nerves?

Taking care of your nerves means taking care of your entire body. Your nerves are part of a large communication network between your brain and your muscles. When you take care of your overall health by eating healthy meals, participating in regular physical activity and following your provider’s treatment plan to manage any underlying conditions, you’re taking care of your nerves, too.

If you have any questions about how you can improve your overall health or the health of your nerves, ask your provider for more information.