What Are the Different Kinds of Epilepsy?
Just as there are many different kinds of seizures, there are many different kinds of epilepsy. Doctors have identified hundreds of different epilepsy syndromes – disorders that have a specific set of symptoms that include epilepsy. Some of these syndromes appear to be inherited. For other syndromes, the cause is unknown. The medications used to treat a particular person will vary depending upon the type of epilepsy. Some types of epilepsy are more responsive to treatment than others. Some epilepsy syndromes remain stable and/or resolve while other epilepsy syndrome may get worse over time.
Epilepsy syndromes are frequently described either by their symptoms, or by the place in the brain where they start.
People with absence epilepsy have repeated absence seizures that cause them to lose consciousness for short periods of time. These seizures almost always start when the person is a child or teenager, and tend to run in families, which suggest that they may be at least partly genetic. Some people with absence seizures may have involuntary movements during their seizures, such as a jerking arm or rapidly blinking eyes. Other people have no noticeable symptoms except for short periods of time when they are “zoned out.” Immediately after an absence seizure, the person can continue to do whatever he or she was doing before the seizure. However, these seizures may occur so often that the person cannot concentrate. Childhood absence epilepsy usually stops when the child reaches puberty. Absence seizures usually have no lasting effect on intelligence or other brain functions.
Temporal lobe epilepsy, or TLE, is the most common epilepsy syndrome with focal seizures. People who have this seizure condition often experience auras. TLE usually begins in childhood. Research has shown that repeated temporal lobe seizures can cause a brain structure called the hippocampus to shrink over time. The hippocampus is important for memory and learning. While it may take years of having temporal lobe seizures for noticeable damage to occur, it is still very important to treat TLE early and as effectively as possible.
With neocortical epilepsy the person has seizures that start in the brain’s outer layer. The seizures can be either focal or generalized. They may include strange sensations, visual hallucinations, emotional changes, muscle spasms, convulsions and other symptoms, depending on where in the brain the seizures begin.
There are many other types of epilepsy, each with its own unique symptoms. Many of these, including Lennox-Gastaut syndrome and Rasmussen’s encephalitis, begin in childhood.
Children with Lennox-Gastaut syndrome have severe epilepsy with several different types of seizures, including atonic seizures, which cause sudden falls and are also called drop attacks. This severe form of epilepsy can be very difficult to treat effectively.
Rasmussen’s encephalitis is a type of epilepsy that gets worse over time. With this kind of epilepsy half of the brain always has inflammation. This epilepsy is sometimes treated with a surgical procedure called hemispherectomy.
Some childhood epilepsy syndromes, such as childhood absence epilepsy, tend to go into remission (meaning they stop progressing) or stop entirely during adolescence. Other syndromes such as juvenile myoclonic epilepsy and Lennox-Gastaut syndrome are usually present for life once they develop. Seizure syndromes do not always appear in childhood, however.
Epilepsy syndromes that are easily treated, do not seem to interfere with understanding or development, and usually stop naturally, are often described as benign. Benign epilepsy syndromes include benign infantile encephalopathy and benign neonatal convulsions.
Other syndromes, such as early myoclonic encephalopathy, include neurological and developmental problems. However, these problems may be caused by underlying deterioration of the nerves rather than by the seizures. Epilepsy syndromes in which the seizures and/or the person’s cognitive abilities get worse over time are called progressive epilepsy.
Several types of epilepsy begin in infancy. The most common type of infantile epilepsy is infantile spasms, clusters or groups of seizures that usually begin before the age of six months. During these seizures the infant may bend their body and cry out.
Have questions about epilepsy?
Visit the My Child Without Limits support community and talk to parents, caregivers, and professionals about their experiences with epilepsy.