How is a person with LGS evaluated for surgery?

Surgery may be used in the treatment of people with LGS under specific situations. The International League Against Epilepsy has recommended approaches to evaluating children for LGS. Additional diagnostic tests and possible surgical approaches have been outlined in a recent article about surgery for patients with LGS. This article suggests that surgical evaluation of people with LGS include:

  • Testing for a potential seizure focus (area where most of seizures begin) with MRI and EEG tests at a pediatric epilepsy center.
  • If a focus can be found, other tests should be done to confirm sites of seizures.
  • If no seizure focus is found, consider vagus nerve stimulation or corpus callosotomy.
  • If a seizure focus is found, testing should be done to make sure the area can be removed safely.
    • If an area can be removed, consider resective surgery. This may mean removal of one or more lobes or area of the brain or almost all of one side of the brain.
    • If a seizure focus is found but can’t be removed safely (without causing more neurological problems in critical areas such as movement, speech or vision), vagus nerve stimulation or corpus callosotomy may be considered.
  • If a corpus callosotomy is done and helps, a person can be re-evaluated to see if a seizure focus can be identified that is causing remaining seizures.

When is resective surgery done and how helpful is it?

The Procedure: Removing a specific area of the brain in a child or adult with epilepsy is done if the majority of seizure activity can be localized to this area and it can be removed without causing serious neurological problems. In some situations, a resection could potentially cure the epilepsy.  In others, surgery may lead to significant improvements in seizure control and quality of life. 

In a child with LGS, seizures usually come from or spread to large areas of the brain, so this type of surgery may not be realistic for many people. However in some instances, problems in one or more areas of the brain can be the cause of seizures in a person with LGS. Some people who have had brain tumors, tubers (lesions or mass seen in tuberous sclerosis), or brain malformations (areas that don’t develop normally) may have seizures that start or involve very specific areas of the brain. If these areas have the most active seizure activity on EEG, they could potentially be considered for this type of surgery.

Outlook:  Resective surgery in a person with LGS aims to control seizures (often just one type of seizure) and does not necessarily change symptoms of other problems. In some situations, cognitive or behavior problems may improve if they had been affected by frequent seizures.

A few studies have shown successful results when surgery is done in certain children with LGS.

  • Lee et al (2010) found that surgery involving removal of one or more areas of the brain improved seizure control in the majority of 27 patients with LGS. Some of the children became seizure free. Improvement in seizures was associated with developmental improvements. However, patients were followed for an average of 33 months and thus long-term outcomes were not known.
  • Liu et al (2012) found that removing one or more areas of the brain can be successful in children when most of the seizure activity (at least 70%) is on one side of the brain. This study looked at outcomes in 18 patients followed for 5.4 years on average. Cognitive function improved in only half of the patients. Younger patients at time of surgery showed more improvement afterwards.
  • Wyllie et al (2007) also found significant improvements in children, especially when an abnormality on MRI was present early in life, even if generalized discharges were seen on EEG.
  • Studies of people with LGS who have had resective surgery are small and some are retrospective, meaning they look at what happened after the procedure has been done. Results of these studies must be considered carefully.

When is a corpus callosotomy needed and how helpful is it?

The Procedure: A corpus callosotomy is a type of surgery designed to help control the most dangerous and disabling seizures, such as atonic, tonic and tonic clonic seizures.  The surgery does not cure the underlying epilepsy. It also is not meant to addresss other problems associated with LGS. However, like other treatments, if a callosotomy can help decrease the severity and frequency of seizures, a person’s thinking and other cognitive problems and behavior may improve over time. 

A corpus callosotomy separates the major connections between the two sides of the brain. Most often, only some of the connections in the corpus callosum are separated – this procedure is called a partial corpus callosotomy. At times, a complete separation of the corpus callosum is needed. This type of surgery is done if a person is not a candidate for resective surgery, if a partial callosotomy doesn’t work, and if other treatments are not appropriate or helpful.

Why it’s done: Since most seizures with LGS are generalized and affect both sides of the brain, splitting the connections between the two sides is intended to prevent the spread of seizure activity from one side to another.

Outlook:   While this surgery is geared to helping the most disabling and dangerous seizures, it’s impact is on more than just the seizures. Improvements in the patient’s and family’s quality of life, as well as potential risks are important to consider.

Some results of corpus callosotomy surgery on seizure control include:

  • Cukiert et al (2006) studied results of 76 patients with LGS or Lennox like syndrome who had a total callosotomy. 91% of patients had more than 50% improvement in generalized seizures  - 52 patients had 90% improvement or more, while 7 patients were seizure free. Attention improved in 86% of patients as well.
  • Kwan et al (2000) presented results of 74 patients from Taiwan who had partial callosotomies; 59 of the patients had LGS. Greater than 50% improvement in seizure control was seen in 66% of patients and 18.9% became seizure free while still on medications.
  • Complications of a corpus callosotomy must also be considered. In addition to possible surgical complications (such as stroke, fluid collections or infection), behavioral changes can occur.
    • A disconnection syndrome consists of problems when the two sides of the brain are separated.  The symptoms seen are more noticeable or significant when the connections or corpus callosum are completely split.  
    • Symptoms may include- weakness on one side of the body, inability to talk (person is mute) or difficulty initiating or starting to talk, problems doing tasks that require transferring information from one side of the brain to the other, difficulties with sequencing, memory and attention.
    • Partial seizures may also increase after surgery in some people.
    • Complications of this surgery may improve over time and rehabilitation will be needed. The long-term outcome may vary with how much separation of the corpus callosum was done as well as other factors.

What other resources should be part of the care team?

Since LGS affects individuals and families in many ways other than seizures, it’s important to include evaluations by other health care professionals when considering treatment options. Specialists in an epilepsy center can help families learn as much as possible about their loved one and the risks and benefits of different treatement options.

Learn the different types of professionals to involve.

Questions to ask:

  • What is the impact of seizures and the underlying neurological problem on my loved one?
  • How do these problems affect my loved one’s daily functioning and quality of life?
  • Will my loved one’s daily functioning change if seizures can be controlled?  What may get worse and is it temporary or permanent? What may get better?
  • What is the effect of seizures or other neurological problems on a person’s mood and behavior? Do medications affect mood and behavior? Will surgery or VNS make these issues better or worse?
  • What types of cognitive problems does my loved one have now? What are his weaknesses and strengths? Will changes occur after a procedure and in what way?
  • What are the benefits and risks of different types of surgery or devices?
  • What are the practical aspects of undergoing these procedures? Some things to consider: amount of time in the hospital for testing and surgery, surgical risks, amount of time out of work for families to help, length of recovery period, if rehabilitation hospitals or programs will be needed, what kind of help be needed after surgery, insurance coverage and out-of-pocket expenses.
  • What types of support are available for families? How can we find these?
  • Are our hopes, goals and expectations realistic?

For more information:

Authored By: 
Patricia O. Shafer RN, MN
Elaine Kiriakopoulos MD, MSc
Joseph I. Sirven, MD
Authored Date: 
Sunday, November 30, 2014