Understanding Epilepsy

Epilepsy is a long-term neurological disorders characterized by epileptic seizures. These seizures are episodes that can vary from brief and nearly undetectable to long periods of vigorous shaking. In epilepsy, seizures tend to recur, and have no immediate underlying cause while seizures that occur due to a specific cause are not deemed to represent epilepsy.

Epilepsy is one of the most common serious neurological disorders affecting about 65
million people globally. It affects 1% of the population by age 20 and 3% of the population by age 75. It is more common in males than females with the overall difference being small. Most of those with the disease (80%) are in the developing world.

There are different types of epilepsy and seizures. Epilepsy drugs are prescribed to control seizures, and rarely surgery is necessary if medications are ineffective.

Causes
Epilepsy has no identifiable cause in about half of those with the condition. In about half the people with epilepsy, the condition may be traced to various factors.

Genetic influence. Some types of epilepsy, which are categorized by the type of seizure you experience, run in families. In these cases, it's likely that there's a genetic influence.

Researchers have linked some types of epilepsy to specific genes, though it's estimated that up to 500 genes could be tied to the condition. 

For most people, genes are only part of the cause of epilepsy. Certain genes may make a person more sensitive to environmental conditions that trigger seizures.

Head trauma. Head trauma that occurs due to a car accident or other traumatic injury can cause epilepsy.

Brain conditions. Brain conditions that result in damage to the brain, such as brain tumors or strokes, also can cause epilepsy. Stroke is a leading cause of epilepsy in adults older than age 35.

Infectious diseases. Infectious diseases, such as meningitis, AIDS and viral encephalitis, can cause epilepsy.

Prenatal injury. Before birth, babies are sensitive to brain damage that could be caused by several factors, such as an infection in the mother, poor nutrition or oxygen deficiencies. This brain damage can result in epilepsy or cerebral palsy.

Developmental disorders. Epilepsy can sometimes be associated with developmental disorders, such as autism and neurofibromatosis.

Symptoms
The main symptoms of epilepsy are repeated seizures. There are many different types of seizure, depending on the area of the brain affected.
People with epilepsy can experience any variety of seizure, although most people follow a consistent pattern of symptoms known as an epilepsy syndrome.

Seizures can occur when you are awake or asleep (nocturnal seizures).
Doctors classify seizures by how much of the brain is affected. There are:
  • partial seizures – where only a small part of the brain is affected
  • generalised seizures – where most or all of the brain is affected

Some seizures do not fit into these categories and are known as unclassified seizures.

Partial Seizures
There are two types of partial seizure:
  • simple partial seizure – where you remain fully conscious throughout
  • complex partial seizure – where you lose your sense of awareness and can’t remember what happened after the seizure has passed

Symptoms of a simple partial seizure include:
  • changes in the way things look, smell, feel, taste or sound
  • an intense feeling that events have happened before (déjà vu)
  • a tingling sensation, or ‘pins and needles’, in your arms and legs
  • a sudden intense emotion, such as fear or joy
  • the muscles in your arms, legs and face may become stiff
  • you may experience twitching on one side of your body

The symptoms of a complex partial seizure normally involve apparently strange and random bodily behaviour, such as:
  • smacking your lips
  • rubbing your hands
  • making random noises
  • moving your arms around
  • picking at clothes
  • fiddling with objects
  • adopting an unusual posture
  • chewing or swallowing

During a complex partial seizure, you will not be able to respond to anyone else, and you will have no memory of the event.
Complex partial seizures are quite common and account for 2 in 10 of all seizures experienced by people with epilepsy.

Generalised Seizures
In most cases, a person having a generalised seizure will be completely unconscious.

There are six main types of generalised seizure:

Absences
Absence seizures, sometimes called petit mal, mainly affect children. They cause the child to lose awareness of their surroundings for up to 20 seconds. The child will seem to stare vacantly into space, although some children will flutter their eyes or smack their lips. The child will have no memory of the seizure.
Absences can occur several times a day. Although they are not dangerous, they may affect the child's performance at school.

Myoclonic jerks
These types of seizures cause your arms, legs or upper body to jerk or twitch, much like if you have received an electric shock. They often only last for a fraction of a second, and you should remain conscious during this time.
Myoclonic jerks often happen in the first few hours after waking up and can occur in combination with other types of generalised seizures.

Clonic seizure
This causes the same sort of twitching as myoclonic jerks, except the symptoms will last longer, normally up to two minutes. Loss of consciousness may occur.

Atonic seizure
Atonic seizures cause all your muscles to suddenly relax, so there is a chance you will fall to the ground. Facial injuries are common with this type of seizure.

Tonic seizure
Unlike an atonic seizure, tonic seizures cause all the muscles to suddenly become stiff. You can lose balance and fall over, so injuries to the back of the head are common.

Tonic-clonic seizure
A tonic-clonic seizure, sometimes known as grand mal, has two stages. Your body will become stiff and then your arms and legs will begin twitching. You will lose consciousness and some people will wet themselves. The seizure normally lasts between one and three minutes, but they can last longer.
This is the most common type of seizure, and about 60% of all seizures experienced by people with epilepsy are tonic-clonic seizures.
Tonic-clonic seizures are what most people think of as an epileptic fit.

Auras
People who have epilepsy often get a distinctive feeling or warning sign that a seizure is on its way. These warning signs are known as auras, but they are actually simple partial seizures.

Auras differ from person to person, but some common auras include:
  • noticing a strange smell or taste
  • having a feeling of déjà vu
  • feeling that the outside world has suddenly become unreal or dreamlike
  • experiencing a sense of fear or anxiety
  • your body suddenly feeling strange

Although this warning cannot prevent the seizure, it can give you time to warn people around you and make sure you are in a safe place.

Status Epilepticus
Status epilepticus is a seizure that lasts longer than 30 minutes or a series of seizures where the person does not regain consciousness in between. If a seizure lasts longer than five minutes, call an ambulance.
Prolonged seizures can be treated with diazepam given as an injection or through someone's rectum. However, if seizures continue because they are not quickly brought under control in this way, it is very important that the patient be transferred to hospital. In hospital, the airways will need to be closely monitored and a high level of sedation may be required to control the seizures.

An alternative treatment is a medication called buccal midazolam. This comes in liquid form and is administered by trickling the liquid onto the inside of your cheek. It is then absorbed into your bloodstream.

You do not have to be a healthcare professional to do this, but you do need the correct training as well as permission from the person who has epilepsy. If you care for someone with epilepsy, you can be trained to administer rectal diazepam or buccal midazolam in case status epilepticus occurs.

Diagnosis
Doctors have developed a number of different tests to determine whether a person has epilepsy and, if so, what kind of seizures the person has. In some cases, people may have symptoms that look very much like a seizure but in fact are nonepileptic events caused by other disorders. Even doctors may not be able to tell the difference between these disorders and epilepsy without close observation and intensive testing.

EEG Monitoring
An EEG records brain waves detected by electrodes placed on the scalp. This is the most common diagnostic test for epilepsy and can detect abnormalities in the brain's electrical activity. People with epilepsy frequently have changes in their normal pattern of brain waves, even when they are not experiencing a seizure. While this type of test can be very useful in diagnosing epilepsy, it is not foolproof. Some people continue to show normal brain wave patterns even after they have experienced a seizure. In other cases, the unusual brain waves are generated deep in the brain where the EEG is unable to detect them. Many people who do not have epilepsy also show some unusual brain activity on an EEG. Whenever possible, an EEG should be performed within 24 hours of a patient's first seizure. Ideally, EEGs should be performed while the patient is sleeping as well as when he or she is awake, because brain activity during sleep is often quite different than at other times.

Video monitoring is often used in conjunction with EEG to determine the nature of a person's seizures. It also can be used in some cases to rule out other disorders such as cardiac arrythmia or narcolepsy that may look like epilepsy.

Brain Scans
One of the most important ways of diagnosing epilepsy is through the use of brain scans. The most commonly used brain scans include CT (computed tomography), PET (positron emission tomography) and MRI (magnetic resonance imaging). CT and MRI scans reveal the structure of the brain, which can be useful for identifying brain tumors, cysts, and other structural abnormalities. PET and an adapted kind of MRI called functional MRI (fMRI) can be used to monitor the brain's activity and detect abnormalities in how it works. SPECT (single photon emission computed tomography) is a relatively new kind of brain scan that is sometimes used to locate seizure foci in the brain.

In some cases, doctors may use an experimental type of brain scan called a magnetoencephalogram, or MEG. MEG detects the magnetic signals generated by neurons to allow doctors to monitor brain activity at different points in the brain over time, revealing different brain functions. While MEG is similar in concept to EEG, it does not require electrodes and it can detect signals from deeper in the brain than an EEG. Doctors also are experimenting with brain scans called magnetic resonance spectroscopy (MRS) that can detect abnormalities in the brain's biochemical processes, and with near-infrared spectroscopy, a technique that can detect oxygen levels in brain tissue.

Medical History
Taking a detailed medical history, including symptoms and duration of the seizures, is still one of the best methods available to determine if a person has epilepsy and what kind of seizures he or she has. The doctor will ask questions about the seizures and any past illnesses or other symptoms a person may have had. Since people who have suffered a seizure often do not remember what happened, caregivers' accounts of the seizure are vital to this evaluation.

Blood Tests
Doctors often take blood samples for testing, particularly when they are examining a child. These blood samples are often screened for metabolic or genetic disorders that may be associated with the seizures. They also may be used to check for underlying problems such as infections, lead poisoning, anemia, and diabetes that may be causing or triggering the seizures.

Developmental, Neurological, and Behavioral Tests
Doctors often use tests devised to measure motor abilities, behavior, and intellectual capacity as a way to determine how the epilepsy is affecting that person. These tests also can provide clues about what kind of epilepsy the person has.

First-Aid
Rolling a person with an active tonic-clonic seizure onto their side and into the recovery position helps prevent fluids from getting into the lungs. Putting fingers, a bite block or tongue depressor in the mouth is not recommended as it might make the person vomit or result in the rescuer being bitten.  Efforts should be taken to prevent further self-injury. Spinal precautions are generally not needed.

If a seizure lasts longer than 5 minutes or if there are more than two seizures in an hour without a return to normal between them it is considered a medical emergency known as status epilepticus. This may require medical help to keep the airway open and protected; a nasopharyngeal airway may be useful for this.  At home the recommended initial medication for seizure of a long duration is midazolam placed in the mouth. Diazepam may also be used rectally.  In hospital, intravenous lorazepam is preferred. If two doses of benzodiazepines are not effective, other medications such as phenytoin are recommended. 

Convulsive status epilepticus that does not respond to initial treatment typically requires admission to the intensive care unit and treatment with stronger agents such as thiopentone or propofol.

Treatments
Doctors generally begin by treating epilepsy with medication. If medications don't treat the condition, doctors may propose surgery or another type of treatment.

Medication
Most people with epilepsy can become seizure-free by taking one anti-seizure medication, called anti-epileptic medication. Others may be able to decrease the frequency and intensity of their seizures by taking medications. Your doctor will advise you about the appropriate time to stop taking medications.

More than half the children with epilepsy who aren't experiencing epilepsy symptoms can eventually discontinue medications and live a seizure-free life. Many adults also can discontinue medications after two or more years without seizures.

Finding the right medication and dosage can be complex. Your doctor will consider your condition, frequency of seizures, your age and other factors when choosing which medication to prescribe. Your doctor will also review any other medications you may be taking, to ensure the anti-epileptic medications won't interact with them.

Your doctor likely will first prescribe a single medication at a relatively low dosage and may increase the dosage gradually until your seizures are well controlled.

Anti-seizure medications may have some side effects. Mild side effects include:
  • Fatigue
  • Dizziness
  • Weight gain
  • Loss of bone density
  • Skin rashes
  • Loss of coordination
  • Speech problems
  • Memory and thinking problems

More severe but rare side effects include:
  • Depression
  • Suicidal thoughts and behaviors
  • Severe rash
  • Inflammation of certain organs, such as your liver

To achieve the best seizure control possible with medication:
  • Take medications exactly as prescribed.
  • Always call your doctor before switching to a generic version of your medication or taking other prescription medications, over-the-counter drugs or herbal remedies.
  • Never stop taking your medication without talking to your doctor.
  • Notify your doctor immediately if you notice new or increased feelings of depression, suicidal thoughts, or unusual changes in your mood or behaviors.
  • Tell your doctor if you have migraines. Doctors may prescribe one of the anti-epileptic medications that can prevent your migraines and treat epilepsy.

At least half of all people newly diagnosed with epilepsy will become seizure-free with their first medication. If anti-epileptic medications don't provide satisfactory results, your doctor may suggest surgery or other therapies. You'll have regular follow-up appointments with your doctor to evaluate your condition and medications.

Therapies
Vagus nerve stimulation. In vagus nerve stimulation, doctors implant a device called a vagus nerve stimulator underneath the skin of your chest, similar to a heart pacemaker. Wires from the stimulator are connected to the vagus nerve in your neck.

The battery-powered device sends bursts of electrical energy through the vagus nerve and to your brain. It's not clear how this inhibits seizures, but the device can usually reduce seizures by 20 to 40 percent.

Most people still need to take anti-epileptic medication, although some people may be able to lower their medication dose. You may experience side effects from vagus nerve stimulation, such as throat pain, hoarse voice, shortness of breath or coughing.

Ketogenic diet. Some children with epilepsy have been able to reduce their seizures by following a strict diet that's high in fats and low in carbohydrates.

In this diet, called a ketogenic diet, the body breaks down fats instead of carbohydrates for energy. After a few years, some children may be able to stop the ketogenic diet and remain seizure-free.

Consult a doctor if you or your child is considering a ketogenic diet. It's important to make sure that your child doesn't become malnourished when taking the diet.

Side effects of a ketogenic diet may include dehydration, constipation, slowed growth because of nutritional deficiencies, and buildup of uric acid in the blood, which can cause kidney stones. These side effects are uncommon if the diet is properly and medically supervised.

Surgery
Surgery is most commonly done when tests show that your seizures originate in a small, well-defined area of your brain that doesn't interfere with vital functions like speech, language, motor function, vision or hearing. In surgery, your doctor removes the area of your brain that's causing the seizures.

If your seizures originate in an area of the brain that controls movement, speech and other functions, you may be awake during part of the surgery. Doctors will monitor you and ask you questions during the procedure.

If your seizures originate in a part of your brain that can't be removed, your doctor may recommend a different type of surgery in which surgeons make several cuts in your brain (multiple subpial transection). These cuts are designed to prevent seizures from spreading to other parts of your brain.

Although many people continue to need some medication to help prevent seizures after successful surgery, you may be able to take fewer drugs and reduce your dosages.

In a small number of cases, surgery for epilepsy can cause complications such as permanently altering your thinking (cognitive) abilities. Talk to your surgeon about his or her experience, success rates and complication rates with the procedure you're considering.

Potential future treatments
Researchers are studying brain stimulation as a potential treatment for epilepsy. In brain stimulation, surgeons implant electrodes into a specific part of your brain. The electrodes are connected to a generator implanted in your chest or the skull that sends electrical pulses to your brain and may reduce your seizures.

Researchers also study stereotactic radiosurgery as a potential treatment for some types of epilepsy. In this procedure, doctors direct radiation at the specific area of your brain that is causing your seizure.

Living with Epilepsy
Uncontrolled seizures and their effect on your life may at times feel overwhelming or lead to depression. It's important not to let epilepsy hold you back. You can still live an active, full life.

To help cope:
  • Educate yourself and your friends and family about epilepsy so that they understand the condition.
  • Try to ignore negative reactions from people. It helps to learn about epilepsy so that you know the facts as opposed to misconceptions about the disease. And try to keep your sense of humor.
  • Live as independently as possible. Continue to work, if possible. If you can't drive because of your seizures, investigate public transportation options near you. If you aren't allowed to drive, you may want to consider moving to a city with good public transportation options.
  • Find a doctor you like and with whom you feel comfortable.
  • Try not to constantly worry about having a seizure.
  • Find an epilepsy support group to meet people who understand what you're going through.

If your seizures are so severe that you can't work outside your home, there are still ways to feel productive and connected to people. You may consider working from home, through working on a computer.

Let people you work and live with know the correct way to handle a seizure in case they are with you when you have one. You may offer them suggestions, such as:
  • Carefully roll the person onto one side.
  • Place something soft under his or her head.
  • Loosen tight neckwear.
  • Don't try to put your fingers or anything else in the person's mouth. No one has ever "swallowed" his or her tongue during a seizure, it's physically impossible.
  • Don't try to restrain someone having a seizure.
  • If the person is moving, clear away dangerous objects.
  • Stay with the person until medical personnel arrive.
  • Observe seizure characteristics such as length, type of movements, direction of head or eye turning. These characteristics may help the doctor diagnose the type of seizure.
  • Time the seizures.
  • Be calm during the seizures.

Prevention
While many cases are not preventable, efforts to reduce head injuries, provide good care around the time of birth, and reduce environmental parasites such as the pork tapeworm may be effective. Efforts in one part of Central America to decrease rates of pork tapeworm resulted in a 50% decrease in new cases of epilepsy.

Prognosis
While epilepsy cannot be cured, for some people the seizures can be controlled with medication, diet, devices, and/or surgery. Most seizures do not cause brain damage, but ongoing uncontrolled seizures may cause brain damage. It is not uncommon for people with epilepsy, especially children, to develop behavioral and emotional problems in conjunction with seizures. Issues may also arise as a result of the stigma attached to having epilepsy, which can led to embarrassment and frustration or bullying, teasing, or avoidance in school and other social settings. For many people with epilepsy, the risk of seizures restricts their independence (some states refuse drivers licenses to people with epilepsy) and recreational activities.

Epilepsy can be a life-threatening condition. Some people with epilepsy are at special risk for abnormally prolonged seizures or sudden unexplained death in epilepsy.

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