Corpus Callosotomy

Corpus callosotomy is a type of epilepsy surgery to treat seizures when antiseizure medications don’t help. The procedure involves a careful surgical cut of a band of fibers (the corpus callosum) connecting the two halves of your brain. Afterward, seizure activity can’t pass from one half of your brain to the other, limiting its spread.


What is a corpus callosotomy?

A corpus callosotomy is a surgical treatment for epilepsy. Epilepsy is a long-term (chronic) condition that causes repeated (recurrent) seizures in children and adults.

During a corpus callosotomy procedure, a healthcare provider called a neurosurgeon carefully places a surgical cut through your brain’s corpus callosum. Your corpus callosum is a band of nerve fibers that connects the two halves of your brain (hemispheres) and relays messages from one side of your brain to the other. A corpus callosotomy stops seizure signals from crossing back and forth between the two hemispheres, limiting the spread of seizure activity. Other names for this procedure include callosal sectioning and brain-splitting.

A corpus callosotomy is one of several different types of epilepsy surgery. Healthcare providers usually reserve this type of surgery for people with severe epilepsy.

What does a corpus callosotomy do?

A surgically separated corpus callosum can’t send seizure signals from one side of your brain to the other. Seizures still occur on the one side of your brain where they start, but they can no longer spread to the other side. After surgery, seizures tend to be less severe because they only affect half of your brain.

What type of seizure does a corpus callosotomy treat?

A corpus callosotomy procedure helps people who experience many atonic seizures despite taking antiseizure medications. If you have an atonic seizure, you suddenly lose muscle strength and collapse or drop to the ground.

An atonic seizure increases your risk of injuries, including broken bones and concussions. Other names for atonic seizures include drop seizures and drop attacks.

A corpus callosotomy isn’t an effective treatment if you experience partial (focal) seizures. These types of seizures develop in a small focal region of your brain but don’t generally spread to the other hemisphere (or side) of your brain. Corpus callosotomy is more helpful when seizures start on one side of your brain and then quickly spread to the other side or hemisphere.


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Procedure Details

What should I expect before a corpus callosotomy?

Your healthcare provider will review presurgical steps with you. You may need some tests to help your provider find where the seizures originate. These tests include:

How is a corpus callosotomy performed?

A corpus callosotomy takes place under general anesthesia, which means you’re asleep throughout the entire procedure. Your neurosurgeon will perform a craniotomy, opening your skull to access your brain.

During the procedure, your surgeon:

  1. Removes a piece of your skull, to create a window for surgical access.
  2. Gently peels back a section of the dura, the tough membrane that protects your brain.
  3. Inserts special instruments to gain access to your corpus callosum, under direct vision using a surgical microscope. Once found, a careful surgical cut is made through your corpus callosum.
  4. Replaces the dura.
  5. Uses stitches or staples to secure your skull bone back into place.

Sometimes, a corpus callosotomy procedure takes place in two stages. During the first stage, your neurosurgeon cuts only the front part of the corpus callosum (anterior corpus callosotomy). This approach allows the two brain sections to continue sharing visual information.

If you continue to have frequent, severe seizures, your healthcare provider may consider a second surgery to sever the corpus callosum completely (complete corpus callosotomy).


What should I expect after a corpus callosotomy?

You’ll spend several days in the hospital. You should be able to get back to everyday activities within six to eight weeks. Some people take longer to recover than others. It depends on many factors, including side effects and the extent of the callosotomy.

A corpus callosotomy doesn’t stop all seizures, so you’ll likely remain on antiseizure medications after the procedure. During recovery, you may temporarily experience:

Risks / Benefits

What are the potential risks or complications of a corpus callosotomy?

Any type of surgical treatment for epilepsy has risks, which your healthcare provider will weigh carefully with the chance you’ll benefit from the procedure. Serious problems after a corpus callosotomy are rare.

Disconnection syndrome is the most common issue after surgery. With your eyes closed, the two sides of your brain don’t cooperate when carrying out simple or complex tasks. For example, the right and left sides of your body can move in conflict with each other.

Other potential corpus callosotomy side effects include:

  • Loss of coordination or balance issues.
  • More partial seizures on one side of your brain.
  • Speech problems, including trouble producing speech and forming words (apraxia), in addition to trouble speaking and/or understanding the speech of those around you (aphasia).
  • Stroke.
  • Swelling in your brain.
  • Hydrocephalus, a condition where water accumulates in your brain. This complication often requires subsequent surgical treatment with an implant, called a shunt.

Recovery and Outlook

What is the corpus callosotomy success rate?

Studies show that a corpus callosotomy is an effective way to reduce seizures when medications don’t work. Up to half of people who have this surgical procedure no longer experience drop attacks. Approximately 1 in 5 people become seizure-free after surgery.

When to Call the Doctor

When should I call my healthcare provider?

After a corpus callosotomy procedure, you should call your healthcare provider if you experience:

  • Fever or other signs of infection at the incision site (your skin is discolored or red, tender or has yellow discharge).
  • More severe or frequent seizures.
  • Severe headaches or nausea.
  • Signs of stroke (slurred speech, blurred vision or sudden paralysis, often. on one side of your body).
  • Speech problems.

A note from Cleveland Clinic

Epileptic seizures are unpredictable. They can disrupt your life and increase your risk of injury. Some can be life-threatening. If antiseizure medications don’t help manage atonic (drop) seizures, your healthcare provider may recommend surgery. The surgery may greatly improve your quality of life. Your provider can talk to you about the benefits and risks of this type of epilepsy surgery specific to your situation.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 02/05/2024.

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