Symptoms of Epilepsy
Epileptic seizures may look very different in different children. Also, there are many kinds of epileptic seizures. Finding out the kind of seizure your child has is important to understanding the causes of the seizures. It helps doctors understand how to control them.
Doctors put seizures in two main categories: partial seizures and generalized seizures. Partial seizures begin in one area of the brain. Generalized seizures seem to affect the entire brain. Knowing whether your child's seizures are partial or generalized is important when choosing treatment.
Different types of seizures cause different sets of symptoms.
Symptoms of generalized seizures
Jerking of the child's muscles or entire body
Increased stiffness (rigidity) in the entire body
Staring spells with blinking
Passing out (loss of consciousness)
Symptoms of partial seizures
Tightening of muscles on one side or part of the body
Jerking of muscles on one side or part of the body
Eyes and head move to one direction
Repetitive chewing and swallowing
Symptoms of both types of seizures
Arrow points to scar tissue where seizures occur.
Children who have partial seizures most often may benefit from surgery. When considering surgery for children with epilepsy, it's very important to find out exactly where in the brain a seizure begins. Researchers at Seattle Children’s are working on many ways to identify where seizures start. Dr. Jeffrey G. Ojemann and his team use both standard and leading-edge techniques.
We have a special area in our hospital devoted to monitoring children’s brain activity. Using video and EEG (electroencephalogram) equipment, we look for clues to their seizures.
Brain tracing shows seizures beginning in one part of the brain (asterisk) and then spreading (double asterisks) to other parts.
If needed, our neurosurgeons also do surgery to place (implant) electrodes on the surface of your child’s brain. These record electrical activity in your child's brain and help us plan for surgery.
Some of the methods we use to find out more about your child's seizures include:
MRI (magnetic resonance imaging)
MRI is a standard procedure that produces high-quality pictures of the inside of the human body. These pictures give your child’s doctor very detailed information about what is happening in your child's brain. Seattle Children’s has the newest 3.0 Tesla MRI scanner, which shows fine detail of the brain and may be better able to show where seizures are beginning.
Sometimes, an MRI scan can identify the part of the brain where seizures start by showing a picture of scar tissue in the brain. We compare this picture with an electrical recording of a seizure in your child’s brain. If they match, we can consider surgery as a way to help treat seizures.
MRI scans do not show us where seizures begin in all children with epilepsy. In these cases, we place electrodes on many parts of your child's brain during surgery. These electrodes can help identify where seizures start. They also identify critical parts of the brain. This process is called brain mapping.
Our doctors also use other types of brain mapping, including the Wada test and functional MRI. With functional MRI, your child moves their hands or looks at pictures during the MRI. This shows the parts of the brain important for a given function, such as hand movements.
PET (positron emission tomography)
The arrow points to where the seizures are coming from. The area is damaged and, between seizures, uses less energy. During the seizure, it uses more energy.
SPECT scan shows the area where a seizure begins (colored circles).
PET scans can show parts of the brain that are using less energy. Sometimes this helps us identify the source of seizures. A test called glucose-PET is one way of creating pictures of how the brain works.
During glucose-PET, we combine a sugar molecule with a small amount of radiation and inject it into your child’s body. The molecule becomes a marker that shows up on a PET scan in certain parts of your child’s brain. This tells us which parts of the brain are working as they should and which are not.
Glucose-PET is helpful in some cases of epilepsy. But sometimes it shows abnormalities that are not related to the epilepsy. For this reason, PET is not used with everyone. It is most often used as one of several tests that help us make decisions about surgery.
Single photon emission computed tomography (SPECT)
SPECT produces a picture that can show us where a seizure is coming from. We use it to measure tissue changes and gain information about blood flow.
A SPECT scan involves a few steps:
- Your child waits at the hospital to have a seizure.
- When the seizure begins, we inject a medicine that helps us see where blood flow is increasing in the brain. This makes a picture we call a SPECT scan.
- We make another SPECT scan when your child is not having a seizure.
- Then we compare the two scans.
SPECT scans can show us where in the brain the seizures begin. During surgery, we place electrodes on the brain to confirm our findings.
Not everyone needs a SPECT scan. It can only be used when children have seizures often enough. They must also know when a seizure is coming so a nurse can inject the medicine early in the seizure. If the seizure is already over, the SPECT scan will not show where the seizure came from.