Epilepsy is a disorder characterized by seizures. Seizures happen when regular brain function is disturbed by excited electrical signals. There are many different types of seizures that start in different areas of the brain and affect different parts of the body. Epilepsy is most common in young children and older adults, but can affect people at any age.
Some types of epilepsy are inherited, others are caused by brain injuries, and still more have an unknown cause. A first seizure that cannot be explained by a medical problem has about a 25 percent chance of returning. A second seizure occurrence means about a 70 percent chance of future seizures, and a diagnosis of epilepsy.
Possible Symptoms of Epilepsy
Doctors have identified two main types of seizures: partial and generalized. Partial seizures are more common than generalized, and occur in one or more areas of the brain. This type of seizure is likely to develop from a specific cause or injury, but can develop for no known reason. Categorized with these two types of seizure are a number of sub-types that affect different areas of the brain or body.
Partial seizures are organized into two categories – simple and complex. Someone having a simple partial seizure does not lose consciousness, and the episode typically lasts about 90 seconds. Someone having a complex partial seizure may lose consciousness briefly, and the episode typically lasts no more than two minutes. A little more than half of adult seizures are complex partial.
Generalized seizures take place over a larger area of the brain, which leads to more serious effects on the person having a seizure. Generalized seizures are organized into two main categories – Grand Mal and Petit Mal. Someone having a grand mal seizure will most likely lose consciousness without warning, with the entire episode lasting 2-3 minutes. Someone having a petit mal seizure will lose consciousness for 3-30 seconds,
and others may not even realize what’s happening. A person may experience as many as 50-100 petit mal seizures per day.
There are many types of epilepsy, and the symptoms can differ greatly between them. The condition leads to an increased risk for falls and accidents, and some people with epilepsy decide to stay away from activities that can become dangerous when a seizure occurs (driving, swimming, etc).
Diagnosing & Treating Epilepsy
Epilepsy is often diagnosed after a visit to the emergency room for a seizure. The most important tool for diagnosing epilepsy is an EEG, ideally performed within 24 hours of a suspected seizure. EEG tests can last from under an hour to an entire day, or even longer-term for patients who do not respond to medications. Multiple tests may be needed, particularly for some types of partial seizures which can show up as normal on an EEG.
First-time seizures are frequently tested with a CT scan. Your doctor may decide to do a CT in addition to another test, which could include an MRI or PET scan. Often these extra texts are done when other tests do not produce quality results. The course of treatment will vary depending on the type of seizure and how often they occur.
Anti-epileptic drugs are used for patients who have had two or three seizures, or after a single seizure if tests show that the person is at risk for another. Treatment for epilepsy is often limited to a single medication, but doctors will add medicines if the condition does not improve. In about one-third of patients, drugs will not control their symptoms. In people whose epilepsy is not helped with medications, surgery may be a
About Epilepsy Surgery
The goal of epilepsy surgery is to reduce or eliminate seizure activity while avoiding damage to other areas of the brain. Your physician will discuss surgical options for treating epilepsy, which could involve removing a lesion or a portion of the affected area.
If medications do not improve your condition, there are two options your doctor may consider for treating your epilepsy with surgery: vagus nerve stimulation (VNS) and resection surgery. The best type of surgery to treat your condition will be determined by your physician. Each treatment course is based on the individual.
VNS uses a device similar to a heart pacemaker that interrupts the signals that lead to seizures. Wires are connected to a nerve in the neck and a battery pack is implanted in the chest area under the skin. These wires send signals to the brain in an attempt to stop a seizure from starting. Once implanted, your doctor will program the device to best suit your physical needs. You will also receive a special magnet that triggers a signal, for use when you feel a seizure starting.
Resection surgery is a procedure that removes or isolates the area of the brain where your seizures start. This type of surgery works best in patients whose seizures always begin in the same area of the brain. It is also important for the affected area to be in a place where surgery can safely be performed, since some areas of the brain are not accessible with current surgical tools and techniques.