Because epileptic seizures provide some of the most visible symptoms of TSC, they are more easily diagnosed than many other manifestations of the disorder. This does not mean that seizures are easily treatable once they're identified. In fact, although the seizures of many people with TSC can be controlled with one medication, some people continue to have seizures despite having taken several types of conventional antiepileptic drugs. This treatment difficulty is due in part to our current limited understanding of the mechanisms that cause seizures, as well as the limited effectiveness of conventional antiepileptic medications.
One drug treatment that has shown particular promise in the treatment of infantile spasms associated with TSC is vigabatrin. Trials have shown a reduction or elimination of seizures in the majority of infants who had experienced infantile spasms prior to treatment. Some people who have been treated with vigabatrin have developed a constriction of their field of vision, suggesting a possible side effect of the drug. Another treatment known as adrenocorticotropic hormone (ACTH) is also effective in reducing or eliminating infantile spasms.
For treatment of partial and generalized seizures associated with TSC, many medications have been found to be effective. However, the success of seizure treatment appears to be as unpredictable as seizures themselves. Most TSC specialists generally recommend against placing people with TSC on several seizure medications at one time, but this is sometimes required to adequately control seizures.
Medications are not the only treatment options TSC specialists use to treat seizures. One alternative therapy that has been successful in reducing or eliminating seizures in some people with TSC is the ketogenic diet, which provides up to 90 percent of its caloric content in the form of fat. Doctors know that consuming foods that are high in fat causes blood acetone levels to rise and blood sugar concentrations to fall. However, exactly how these changes affect the frequency of seizures remains unclear. And yet, some people with TSC—especially those who experience myoclonic or atonic seizures—have shown improvement on the diet.
The vagus nerve stimulator (VNS) is another alternative therapy physicians use to treat seizures in people with TSC, especially those whose seizures have been unresponsive to drug therapy. This technique relies on a pacemaker-like device that is implanted under the skin of the chest and supplies intermittent electrical impulses to the vagus nerve as it passes through the neck. Researchers have found that intermittent stimulation of this nerve with low-intensity electrical impulses can be helpful in reducing seizures in people with TSC.
Although brain surgery is not often required for people with TSC, it may be the best option for people who suffer from intractable seizures. This requires that physicians be able to identify, using EEG readings and MRI images, a single source of all clinical seizure activity—typically a single cortical tuber. In these cases, neurosurgeons have removed such tubers and successfully reduced or eliminated seizures without negatively impacting brain function.
It is important to remember:
- Seizures affect between 60 and 90 percent of people with TSC, and often provide the first sign of the disorder.
- Seizures result from abnormal electrical impulses in the brain. In people with TSC, they may be related to the presence of cortical tubers.
- It is critical that infantile spasms be recognized and treated promptly in order to lower the risk that the child will develop serious neurological complications. They most often affect infants between the ages of five and nine months.
- Some of the most common types of seizures seen in people with TSC are infantile spasms, simple partial, complex partial, and generalized tonic-clonic seizures.
- Treatment options for seizures include medications, and alternative therapies such as the ketogenic diet and the vagus nerve stimulator (VNS).
- Although identification of seizures can be relatively simple, treating seizures can be difficult.
- Surgery may play an important role in managing epilepsy in individuals with TSC who have intractable seizures.
- It is important to find a neurologist who is familiar with TSC-related brain abnormalities and their neurological consequences.
A neurologist is a physician who specializes in disorders of the nervous system. A neurologist who treats people with TSC is trained to recognize the neurological symptoms and brain abnormalities characteristic of the disorder.
A neurosurgeon is a surgeon who specializes in performing surgery on the central nervous system, including the brain. A neurosurgeon who treats people with TSC is trained in the identification and removal of SEGAs. A neurosurgeon who specializes in epilepsy surgery is trained in the removal of specific regions of the cerebral cortex identified as the primary location of seizure activity. A neurosurgeon may also be trained to implant a vagus nerve stimulator (VNS) to help control seizures.
A nutritionist is a medical professional who specializes in diet and metabolism. A nutritionist who is knowledgeable about TSC-related seizures and has had specialized training in administering the ketogenic diet can provide background and instructions on how to implement this alternative therapy.
You can find a list of on-staff physicians on the Herscot Center for Children and Adults with TSC Web site.
Epilepsy.com is an educational resource for individuals and families affected by epilepsy.
The Epilepsy Foundation provides education and advocacy for people affected by epilepsy.