What is a corpus callosotomy?

Corpus callosotomy is a surgical procedure used to treat atonic seizures, also called drop attacks, by dividing all or part of the corpus callosum. The corpus callosum is the bundle of nerve fibers that connects the two brain hemispheres. The procedure prevents seizures from spreading from one half of the brain to the other.

Corpus callosotomy surgery does not completely eliminate seizures, but it prevents them from affecting the entire brain and muscles on both sides of the body. After corpus callosotomy surgery, a seizure may affect muscles on one side of the body, but muscle tone on the other side will be maintained, reducing the risk of injury from falls.

Corpus callosotomy does not split all connection between the two hemispheres of the brain. While the corpus callosum is the primary nerve connection between the hemispheres, connections are also present in other areas that are not affected by the procedure.

Though subtle changes in certain abilities can be experienced by patients after corpus callosotomy, the surgery generally does not impact your child’s day-to-day life.

Who is a candidate for corpus callosotomy?

Corpus callosotomy surgery is considered as an option for children with atonic seizures that aren’t controlled by medication. These are known as uncontrolled refractory, or drug-resistant seizures.

The procedure can also be used to treat other types of generalized seizures — seizures that spread from one hemisphere to the other — and can help reduce the length of a seizure.

How is corpus callosotomy surgery performed?

Corpus callosotomy surgery is performed while your child is under general anesthesia.

Two methods are used for the procedure.

• Conventional method: A small incision is made in the scalp at the top of the head, and a section of the skull is removed. The neurosurgeon gently separates the two hemispheres and uses special instruments and surgical microscopes to disconnect the corpus callosum or to cut part of it. The section of skull removed at the start of the procedure is then replaced and fixed in position, and the skin incision is closed.
• Laser ablation brain surgery: Two to three small holes are made in the skull and the laser surgery is guided by magnetic resonance imaging (MRI). Heat from the precisely focused laser beam cuts the corpus callosum. Nearby brain tissue is not affected, and no brain tissue is touched or moved to gain access to the corpus callosum.

In some cases, corpus callosotomy is done in two stages, leaving some of the connections uncut to allow the two hemispheres to share some information. If seizures persist, a second procedure can be done to cut the rest.

What to expect

On the day of the surgery and immediately after

On the day of the corpus callosotomy surgery, your child will undergo general anesthesia. At Children’s Hospital of Philadelphia (CHOP), you can trust our specially trained pediatric anesthesiologists to keep your child comfortable and safe before, during and after their procedure. Read more about our dedicated pediatric anesthesiology team.

The procedure itself takes several hours, or less in the case of laser ablation surgery. Recovery times depend on the surgical method used.

If the conventional method is used, your child will be monitored in the Pediatric Intensive Care Unit (PICU) for the first day after surgery. Then your child will be moved to the Epilepsy Monitoring Unit (EMU) to continue recovering for another few days.

If the laser ablation technique is used, your child will be monitored for the hours after surgery, then discharged from the hospital within one or two days.

Going home after corpus callosotomy surgery

Your child will gradually be able to resume normal activities over the following few weeks, and will be able to return to school two to four weeks after surgery. If your child had laser ablation, they should be able to resume normal activities in about two weeks.

Anti-seizure medications will generally be continued unchanged after the procedure.

Your child will return to CHOP for periodic follow-up visits after the procedure, on a schedule determined by your child’s medical team.

Corpus callosotomy reduces generalized seizure frequency by 70 to 90 percent in most patients, and stops drop attacks in 50 to 75 percent of cases.

Why choose CHOP for corpus callosotomy surgery

At Children’s Hospital of Philadelphia, your child will have access to pediatric experts from the Division of Neurosurgery, the Pediatric Epilepsy Program and others who specialize in the care of children with epilepsy and seizures.

Our team of experts work closely together to ensure that patients are screened appropriately for corpus callosotomy, and to provide the full range of supportive therapy before and after epilepsy surgery to optimize outcomes.