WHAT IS EPILEPSY?
Epilepsy is a neurological disorder that affects people in every country throughout the world. Epilepsy is also one of the oldest conditions known to mankind. It is characterized by a tendency to recurrent seizures and it defined by two or more unprovoked seizures. The belief widely held in many countries is that a person with epilepsy is seized by a supernatural force or power. This ancient belief is reflected in the name of the disorder — the word “epilepsy” being derived from the Greek word “epilambanein” which means “to seize or attack”.
Epilepsy is a general term that includes various types of seizures. People with diagnosed epilepsy have had more than one seizure, and they may have had more than one kind of seizure.
A seizure happens when abnormal electrical activity in the brain causes an involuntary change in body movement or function, sensation, awareness, or behavior. Seizures are the result of sudden, usually brief, excessive electrical discharges in a group of brain cells (neurons) and that different parts of the brain can be the site of such discharges.
Epileptic seizures vary in severity and frequency, and even in the time of day they occur. While some people may experience no more than two or three seizures during their entire lifetime, others will have several seizures in one day. An epileptic seizure occurs when these energy pulses come much more rapidly-as many as 500 per second for a short time-due to an electrical abnormality in the brain. This brief electrical surge can happen in just a small area of the brain, or it can affect the whole brain.
The clinical manifestations of seizures will therefore vary and depend on where in the brain the disturbance first starts and how far it spreads. Transient symptoms can occur, such as loss of awareness or consciousness and disturbances of movement, sensation (including vision, hearing and taste), mood or mental function.
Epilepsy is characterized by unprovoked, recurring seizures that disrupt the nervous system and can cause mental and physical dysfunction. It affects all age groups. About 14% of epilepsy patients are under 15 years old and 24% are over 64, with 62% being between those ages. Epilepsy is decreasing in childhood but increasing in the elderly, probably because of mild strokes and cardiac arrest.
WHAT ARE THE TYPES OF EPILEPSY?
There are several types of epilepsy, each with different causes, symptoms and treatments. Epilepsy can be divided into two broad categories:
Idiopathic epilepsy is thought to be caused by genetic factors, as opposed to brain damage. Based on the type of seizures it can be categorized in to:
- Idiopathic generalized epilepsy
Idiopathic generalized epilepsy is a genetic and inherited group of disorders generally with a family history of epilepsy. Idiopathic generalized epilepsy tends to appear during childhood or adolescence, although it may not be diagnosed until adulthood. In this type of epilepsy, there are no nervous system (brain or spinal cord) abnormalities other than the seizures. The brain is structurally normal. People with idiopathic generalized epilepsy have normal intelligence and the results of the neurological examination and brain scan are normal. The results of the electroencephalogram (EEG – a test which measures electrical impulses in the brain) may show epileptic discharges affecting the entire brain. The types of seizures affecting patients with idiopathic generalized epilepsy may include myoclonic seizures, absence seizures, and generalized tonic-clonic seizures. Idiopathic generalized epilepsy is usually treated with medications and is a condition that may be outgrown, as is the case with childhood absence epilepsy.
- Idiopathic partial epilepsies
Idiopathic partial epilepsy begins in childhood (between ages 5 and 8) and may have a family history. Also known as benign focal epilepsy of childhood, this is one of the mildest types of epilepsy. It is almost always outgrown by puberty and is never diagnosed in adults. Seizures tend to occur during sleep and are most often simple partial motor seizures that involve the face and secondarily generalized (grand mal) seizures.
Symptomatic epilepsy is caused by physical defects in the brain. It can be classified into :
- Symptomatic generalized epilepsy
Symptomatic generalized epilepsy is caused by widespread brain damage. Injury during birth is the most common cause of symptomatic generalized epilepsy. In addition to seizures, these patients often have other neurological problems, such as mental retardation or cerebral palsy. Specific, inherited brain diseases, such as adrenoleukodystrophy (ADL) or brain infections (such as meningitis and encephalitis) can also cause symptomatic generalized epilepsy. When the cause of symptomatic general epilepsy cannot be identified, the disorder may be referred to as cryptogenic epilepsy. These epilepsies include different subtypes — the most typical is the Lennox-Gastaut syndrome. Multiple types of seizures (generalized tonic-clonic, tonic-myoclonic, tonic-atonic and absence seizures) are common in these patients and can be difficult to control.
- Symptomatic partial epilepsy
Symptomatic partial (or focal) epilepsy is the most common type of epilepsy that begins in adulthood. This type of epilepsy is caused by a localized abnormality of the brain, which can result from strokes, tumors, trauma, congenital (present at birth) brain abnormality, scarring or “sclerosis” of brain tissue, cysts or infections. Sometimes these brain abnormalities can be seen on magnetic resonance imaging (MRI) scans, but often they cannot be identified, despite repeated attempts, because they are microscopic.
WHAT ARE THE COMMON TYPES OF EPILEPSY?
There are hundreds of epilepsy syndromes, many of them very rare. These syndromes are often named for their symptoms or for the part of the brain where they originate. Each type of epilepsy has different behavioral effects and is treated with different methods. Many of these epilepsy syndromes originate in childhood or even in infancy.
Others begin in adulthood and even in old age. Except for different types of seizures, some of the most common types of epilepsy are:
People with absence epilepsy have repeated absence seizures. Absence epilepsy tends to run in families. The seizures frequently begin in childhood or adolescence. If the seizures begin in childhood, they usually stop at puberty. Although the seizures don’t have a lasting effect on intelligence or other brain functions, children with absence epilepsy frequently have so many seizures that it interferes with school and other normal activities.
Temporal Lobe Epilepsy
Temporal lobe epilepsy (TLE) is the most frequent cause of partial seizures and aura. The temporal lobe is located close to the ear. It is the part of the brain where smell is processed and where the choice is made to express a thought or remain silent. TLE often begins in childhood. Repeated TLE seizures can damage the hippocampus, a part of the brain that is important for memory and learning. Although the damage progresses very slowly, it is important to treat TLE as early as possible.
Frontal Lobe Epilepsy
The frontal lobes of the brain lie behind the forehead. They are the largest of the five lobes and are thought to be the centers that control personality and higher thought processes, including language and speech. Frontal lobe epilepsy causes a cluster of short seizures that start and stop suddenly. The symptoms depend upon the part of the frontal lobe affected.
Occipital Lobe Epilepsy
The occipital lobe lies at the back of the skull. Occipital lobe epilepsy is like frontal and temporal lobe epilepsies, except that the seizures usually begin with visual hallucinations, rapid blinking, and other symptoms related to the eyes.
Parietal Lobe Epilepsy
The parietal lobe lies between the frontal and temporal lobes. Parietal lobe epilepsy is similar to other types in part because parietal lobe seizures tend to spread to other areas of the brain.
WHAT CAUSES EPILEPSY?
Unlike some medical conditions, epilepsy is not necessarily something a person is born with. Epilepsy is often, but not always, the result of an underlying brain disease. Any type of brain disease can cause epilepsy, but not all people with the same brain disease will have epilepsy. In view of the fact that only a proportion of people who have a brain disease experience seizures as a symptom of that disease, it is suspected that those who do have such symptomatic seizures are more vulnerable due to biochemical/neurotransmitter reasons.
The causes of epilepsy are not known, but some scientists believe that seizures can result from a number of unrelated conditions like:
- Illness or high fever.
- Exposure to toxic substances.
- Electrolyte imbalances.
- Genetic Mutations.
- Underlying brain disease- tumor, cerebrovascular disease.
- Neuron-cysticercosis cysts on the brain caused by tapeworm infection.
- Malaria,Meningitis and Tuberculosis.
- Febrile illness of any kind.
There are still many people for whom the cause of their epilepsy cannot, as yet, be identified. In such cases, the theory most commonly accepted is that this epilepsy is the result of an imbalance of certain chemicals in the brain (especially chemical messengers known as neurotransmitters) causing them to have a low convulsive threshold.
AT WHAT AGE IS ONE MORE PRONE TO SUFFER FROM EPILEPSY?
The most common ages of onset for epilepsy are for those under the age of 18 and those over the age of 65. It has been estimated that about 4% of the population has some form of epilepsy, but some theorize that the incidence may be much higher in fact. A significant and measurable decline in cognitive function is known to be associated with epilepsy although it has not been entirely clear to what extent this is due to the epilepsy itself or to the drugs used to treat it. Newer anti-epileptic drugs are considered by some to have less severe cognitive effects than older drugs. On an individual level, a person’s reaction to epileptic seizures and/or anti-epileptic drugs may be idiosyncratic so it is sometimes difficult to predict how a particular person might be affected.
HOW DOES GENETIC MUTATION CAUSE EPILEPSY?
Mutations in several genes have been linked to some types of epilepsy. Several genes that code for protein subunits of voltage-gated and ligand-gated ion channels have been associated with forms of generalized epilepsy and infantile seizure syndromes. Several ligand-gated ion channels have been linked to some types of frontal and generalized epilepsies. Epilepsy-related mutations in some non-ion channel genes have also been identified.
Children and adolescents are more likely to have epilepsy of unknown or genetic origin. The older the patient, the more likely it is that the cause is an underlying brain disease, such as a brain tumor or cerebro-vascular disease, or is the result of head injury. Trauma and brain infection can cause epilepsy at any age, and as mentioned previously may account for a higher incidence of epilepsy in developing countries. For example, a common cause in Latin America is
WHAT CAUSES EPILEPSY IN CHILDREN?
Epilepsy is characterized by repeated seizures that may occur as often as several times a day, or as infrequently as once every few months. Normally, millions of tiny electrical charges pass between nerve cells in the brain and throughout the body to control the body’s many functions. Epileptic seizures are caused by unusual and strong bursts of electrical energy in the brain. There are many possible causes of epilepsy in children:
- Problems with brain development before birth.
- Lack of oxygen during or following birth.
- A head injury that leaves a scar in the brain.
- Unusual structures in the brain.
- A prolonged seizure with fever.
- After-effects of severe brain infections such as meningitis or encephalitis
When a cause can be identified, children will be described as having symptomatic epilepsy. The seizures are thought to be a symptom of the underlying brain injury.
Febrile seizures are caused by high fever and usually occur between the ages of three months and five years. Between 10% and 15% of children with epilepsy have a history of febrile seizures before they develop the disease. It should be strongly noted, however, that febrile seizures are quite common and occur in about 3% of all children under five years old. Nearly all are brief and have no long-lasting effect.
Epilepsy may be the most common genetic neurological disease, but dozens of genetic syndromes representing a variety of seizure patterns may account for the different forms this disease takes. To date, however, researchers have identified only two epilepsy syndromes that are known to be caused by single genetic defects:
- Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE). ADNFLE is now believed to be caused by an alteration in a receptor in the brain called neuronal nicotinic acetylcholine.
- Benign familial neonatal convulsions (BFNC). BFNC appears to be caused by genetic defects that affect ion channels in nerve cells that carry potassium.
In women and children, high fever from a vaccination can, in rare instances, trigger seizures, which are almost always temporary and have no serious consequences. Some controversy arose a few years ago over the possibility that the DTP (diphtheria-tetanus-pertussis) vaccine might trigger epilepsy or other neurological diseases. Some experts suggest that children who have neurological events following their DTP shot already have a preexisting impairment such as epilepsy, which is revealed but not caused by the vaccine. Children with existing epilepsy may be at risk for seizures two or three days after the vaccination. Such a temporary worsening of their disease does not appear to pose a danger to the child. Infants with suspected neurological problems may have their vaccinations delayed until their neurological situation is clarified, but not beyond their first birthday.
Head injuries in infants and children
Infants are at high risk for head trauma. In fact, one study suggested that any infant with scalp fracture that occurs with a hematoma may be at risk for brain injury. A hematoma occurs after an injury when blood collects in a mass that usually looks like a large purplish area. It should be noted that hematoma is quite common after delivery when it typically causes no problems.
Childhood viral infections
Human herpes virus 6 was particularly associated with severe seizures. Herpes virus 6 is common in children and causes roseola infantum, an acute illness that can lead to high fever and skin rash but is usually benign.
Hydrocephalus and shunts
Hydrocephalus is a condition that may occur in newborns and infants in which cerebrospinal fluid (CSF) accumulates in the brain, leading to excessive swelling of the spaces in the brain (ventricles). The resulting pressure can damage the brain’s tissue. Hydrocephalus itself is not commonly known to cause seizures, but its treatment, which involves insertion of a shunt, may be. The shunt is a device that drains the excess fluid from the brain to other parts of the body, as well as to a special reservoir that allows the shunt to be reached through the skin.
This is an abnormality in fetal development in which the normal migration of nerve cells is altered.
Other causes in children
Seizures in infants and children may be due to birth defects, difficulties during delivery, or poisoning. Melatonin- n herbal remedy available over the counter for sleep disorders, has been found to cause seizures in children who have existing neurological problems.
WHAT FACTORS TRIGGER EPILEPSY?
In most cases, there is no known cause for epileptic seizures, but the following have been known to trigger them:
Inadequate sleep can set off seizures in some people.
Food allergies might provoke some seizures in children who also have migraine headaches, hyperactive behavior, and abdominal pains. Parents should consult an allergist if they suspect foods or additives might be playing a role in such cases.
Alcohol and smoking
Alcohol and smoking should be avoided, although light alcohol consumption does not appear to increase seizure activity in people who are not alcoholics or sensitive to alcohol.
Patients should avoid exposure to flashing or strobe lights. Video games have been known to trigger seizures in people with existing epilepsy, but apparently only if they are already sensitive to flashing lights. Seizures have been reported in Japan among people who watched cartoons with rapidly fluctuating colors and quick flashes. The frequency of flashes per second is measured in hertz (Hz). Screens that emit a lower hertz are more likely to cause seizures in people with epilepsy than a higher-hertz screen.
Damage occurring to the brain as it develops during the first three months of pregnancy. This can be revealed by modern MR scans and causes many of the difficult-to-control cases in children. On the other hand, damage inflicted during delivery (cerebral palsy) is fairly uncommon.
Brain tumors especially slow-growing superficial tumors may trigger epilepsy. Since these can be surgically removed, it is important to check for these if a patient develops epilepsy, especially if the attacks start in a limited part of the brain. The most important techniques are CT and MR scans.
WHAT ARE GENERALLY COMMON TYPES OF EPILEPSY SEIZURES?
Epilepsy is caused by a problem in communication between the brain’s nerve cells. Normally, such cells communicate with one another by sending tiny electrical signals back and forth. For someone with epilepsy, the signals from one group of nerve cells occasionally become too strong, so strong that they overwhelm neighboring parts of the brain. It is this sudden, excessive electrical discharge that causes the basic symptom of epilepsy, which is called an epileptic seizure, fit, or convulsion. It is not yet known what causes the brain’s communication system to misfire in this fashion.
Almost any type of behavior that happens repetitively may represent a seizure. There are several different types of seizures that can be manifest in the pediatric age group. Some of the common types of seizures are:
- Generalized tonic-clonic seizures (grand mal seizures).
- Partial seizures.
- Absence seizures.
During childhood however there are several other conditions that may be mistaken for seizures. Some of the common entities that are misdiagnosed as seizures are:
- Breath holding spells.
- Psychological conditions.
- Staring spells due to inattention
The seizures may occur rarely or every day. Many people with epilepsy have no symptoms between seizures and lead normal lives. Some people have no symptoms for years and may be weaned off medication.
WHAT ARE THE SYMPTOMS OF EPILEPSY?
There are many forms of epilepsy, each with its own characteristic symptoms. The basic symptom of epilepsy is a brief and abnormal phase of behavior, commonly known as a seizure, fit or convulsion. It is important to realize that a single such episode does not indicate that the individual has epilepsy. By definition, epileptic seizures recur.
An aura is usually the first symptom experienced during a seizure. Aura can occur just prior to the occurrence of the seizure or as much as several hours before it strikes. Many epileptics learn to recognize their special aura, and this may give them time to avoid accidents when they become unconscious. An aura may typically consist:
- Sense of tension.
- An ill-defined feeling.
- An impression of smelling unpleasant odors.
- Hearing peculiar sounds.
- Distorted vision.
- An odd bodily sensation-particularly in the stomach.
Petit mal epilepsy is a disease of childhood that does not usually persist past late adolescence. A child may have this form of epilepsy if, from time to time, he or she suddenly stops whatever activity is going on and stares blankly around for a few seconds (sometimes up to half a minute). During the blank interval, known as a petit mal seizure, the child is unaware of what is happening. There may be a slight jerking movement of the head or an arm, but petit mal seizures do not generally involve falling to the ground. When the seizure ends, the child often does not realize that the brief blank spell has occurred. Such children are sometimes thought simply to be “day-dreamers.”
The most characteristic symptom of grand mal epilepsy is a much more dramatic seizure. The person falls to the ground unconscious and then the entire body stiffens. Next, it twitches or jerks uncontrollably. This may last for several minutes and is usually followed by a period of deep sleep or mental confusion. During a seizure, some people lose bladder control and pass urine freely. In many cases, the person gets a warning of an impending seizure by having certain strange sensations before losing consciousness.
Breath holding spells may occur in toddlers. They occur in response to a minor injury or as an emotional response if a toddler gets upset and cries. During an episode a child cries out and then seems to hold his breath. His lips and mucous membranes may appear bluish (cyanotic breath holding spell) or less commonly, a child may appear very pale (pallid breath holding spell) during an episode. If the episode is prolonged, it may result in a generalized convulsion. It is important to distinguish such a convulsion from an epileptic seizure. Consultation with the primary care provider is the first step, and if necessary further subspecialty consultation with a neurologist may be obtained for accurate diagnosis.
Syncope or fainting occurs when a patient falls down and has a brief loss of consciousness. Misdiagnosis with epileptic seizures may occur if there is no clear history of a precipitating cause, while on the other hand, although infrequent, some epileptic seizures may have syncope as one of their manifestations. Some of the common causes which may lead to syncope are:
- Sudden emotional stress.
- Severe pain.
- Sudden standing up.
- Prolonged standing.
There are two other types of epilepsy with their specific symptoms.
A person with focal epilepsy does not necessarily lose consciousness; the seizure begins with uncontrollable twitching of a small part of the body, and the twitch gradually spreads. The thumb of one hand, for instance, may start to jerk, followed by a jerking of the entire arm and then of the rest of that side of the body, after which there may be a more generalized seizure of the entire body.
Temporal Lobe Epilepsy
A person with temporal lobe epilepsy is likely to have an aura lasting only a few seconds. Then, without being aware, the individual does something entirely out of character, such as becoming suddenly angry, laughing for no apparent reason, or interrupting normal activity with some sort of bizarre behavior. Strange, chewing movements of the mouth are apt to occur throughout any such episode.
HOW IS EPILEPSY DIAGNOSED?
Diagnosing epilepsy can be difficult and the physician will:
- Study the patient’s history.
- Do thorough physical and neurological evaluations.
- Run a variety of tests.
What happens just before a seizure, during a seizure and right after a seizure can help the doctor make a diagnosis. Taking a medical history can help rule out non-epilepsy conditions that might have caused the seizures. Making an accurate diagnosis is vital in planning the correct treatment to control seizures. Misdiagnosis followed by the wrong treatment is one reason why people sometimes keep having seizures. Inappropriate treatment also results in unnecessary side effects from medication.
Routine lab tests may be done to check for other medical conditions that might be causing the seizures. Some of these tests could be:
- Complete blood counts (CBC)
It is used to check for infection, abnormal electrolyte levels (such as magnesium, potassium and calcium), signs of kidney or liver malfunction and other common problems.
- Lumbar puncture
A lumbar puncture (sometimes called a spinal tap) rules out infections, such as meningitis and encephalitis.
- Toxicology screenings
It is done for poisons, illegal drugs or other toxins.
Various tests are conducted to carry out neurological assessment. These are:
- EEG (Electroencephalogram)
The EEG is a record of the patient’s electrical brain activity. It is carried out by placing an array of electrodes on the patient’s scalp, held temporarily in place with an adhesive. Disturbance of brain waves can provide significant clues to the nature of an epileptic syndrome. An outpatient EEG recording usually takes up to 1-2 hours. EEG recording during sleep is also carried out. To facilitate this, patient’s sleep is restricted to 4-6 hours during the previous 24 hours. This enables the patient to fall asleep during the recording.
- Video and EEG monitoring
It can be performed at the same time to record seizures on videotape and computer so that the doctor can see what happens just before, during and right after a seizure. The video records what the body is doing, and the EEG records the electrical activity occurring in the brain. Such monitoring may be used prior to surgery or when repeated EEG tests have not provided enough clues as to the type of seizure or to diagnose psychogenic seizures.
- MRI and CT Scans
Magnetic resonance imaging (MRI) and computed tomography (CT) scans may be used to evaluate the cause and the location of a possible source of epilepsy within the brain. The scans can reveal scar tissue, tumors or structural problems in the brain. These tests also may be used before epilepsy surgery to pinpoint the exact location of a problem in the brain.
WHAT IS THE EFFECT OF EPILEPSY ON THE LIFESTYLE OF AN INDIVIDUAL?
Epilepsy is generally associated with several myths and prejudices. As the name suggests it is related to demonic powers control over the patient and carries a social stigma in most countries. This results in many cases being unreported and patients trying psychic healing. Uncontrolled seizures can have a big impact on lifestyle like:
- Restricting the individual from driving.
- Restricting and limiting their work.
- Restrictions on leisure time activities like swimming etc.
Although seizures themselves usually are not physically harmful to people who have epilepsy, they carry a risk of injury and death. The risk is greater for people, who have many seizures, depending on the type of seizure they have.
Unexpected seizures can cause falls, drowning or other accidents, and a lengthy seizure condition (status epilepticus) can lead to coma or death. By reducing or stopping seizures, treatment may greatly improve the patient’s quality of life and safety.
WHAT TREATMENT OPTIONS ARE AVAILABLE FOR EPILEPSY?
For most people with epilepsy, treatment can reduce or prevent seizures and allow many patients to remain free of seizures for the rest of their lives.
The proper emergency response to a Generalized Tonic/Clonic epileptic seizure is simply to prevent the patient from suffering an injury. This is achieved by:
- Moving him or her away from sharp edges.
- Placing something soft beneath the head.
- Carefully moving the person onto his or her side to avoid asphyxiation.
If the seizure lasts longer than 3-4 minutes, contact Emergency Medical Services immediately, as this may indicate the presence of Status Epilepticus, a potentially fatal condition. One should never place any object in a person’s mouth during a seizure as this could result in injury to the victim’s mouth. Despite common folklore, it is not possible for a person to swallow the tongue during a seizure.
Epilepsy is often treated with:
- Neuro-cybernetic prostheses (similar to a heart pacemaker).
- Specialized diet
Some sufferers receive a special kind of dog which has the rare talent of sensing the onset of a seizure and are trained to alert the human so they can reach a safe location before their seizure puts them in danger.
Status epilepticus is a prolonged seizure or cluster of seizures that requires emergency treatment whether or not the individual has epilepsy. A seizure or cluster of seizures that goes on for more than 20 to 30 minutes during which the person does not wake up can cause brain damage. Treatment with antiepileptic medications needs to be started immediately for any seizure lasting more than five minutes. Medication used to end the seizure is given through an IV (intravenously) so that it takes effect more quickly. If IV medication is not available, medication may be given rectally or as a shot in the muscle.
WHAT IS NEURO-CYBERNETIC PROSTHESES FOR TREATING EPILEPSY?
Vagus nerve stimulation is a recently developed form of seizure control which uses an implanted electrical device, similar in size, shape and implant location to a heart pacemaker, which connects to the vagus nerve in the neck. Once in place the device can be set to emit electronic pulses to the vagus nerve at pre-set intervals and milliamp levels. Treatment studies have shown that approximately 50% of epileptics treated in this fashion will show significant seizure reduction. Vagus nerve stimulation is effective in treatment of seizures in some cases. The stimulator is a battery powered device similar to a pacemaker and is implanted under the skin in the upper left chest wall. From the stimulator a lead is tunneled under the skin and attached to the left vagus nerve in the lower part of the neck. The batteries last from three to five years and need replacement after that.
WHAT EPILEPSY MEDICATIONS ARE AVAILABLE?
Depending on the seizure type, different treatments may be prescribed. Most people with epilepsy can become free of their seizures by using a single antiepileptic drug. For others, medication can make seizures less frequent and less intense. More than half of children with epilepsy whose seizures are controlled by medications can eventually stop their medications and live a seizure-free life. Many adults also can discontinue medication after two or more years without seizures.
There are a large number of medicines available for treatment of epilepsy. Finding the right medication and dosage can be complex. It might take more than one drug, or trying several different drugs until the right one is found. It is important to consult a physician for proper medication since there are some serious side effects of these medicines. Some of these side effects could be:
- Liver problems.
- Stomach problems.
- Blood disorders
- Hair loss.
- Personality changes like irritability.
- Double vision.
- Shrinking gums.
- Growth of body hair
IS SURGERY A SAFE OPTION FOR TREATING EPILEPSY?
Surgical techniques to remove injured brain tissue may be appropriate for many patients with epilepsy. The surgeon’s goal is to remove only the damaged tissue in order to prevent seizures and to avoid damage to healthy brain tissue.
Surgery has become a safer option in recent years because of advances in brain imaging and surgical techniques that make it possible to pinpoint the area of the brain where the seizures occur, and to remove just that area. The goal is to remove just enough of the damaged brain tissue to stop seizures. The most common form of epilepsy involves seizures that begin in the brain’s temporal lobes, the sections along the sides of the woman’s brain. This type of epilepsy is the hardest to control with medication, but it is the type most likely to respond to surgical treatment.
The first step is to pinpoint the area of the brain where the abnormal electrical activity happens. This area can be found by long-term EEG monitoring with help from MRI and PET scans. Functional MRI can be used to determine whether the affected brain cells perform a vital function. Surgeons avoid operating on areas of the brain that control speech, language, hearing, and other vital functions.
WHAT ARE THE SURGERIES AVAILABLE TO CURE EPILEPSY?
The different types of surgical procedures undertaken for curing epilepsy are listed here.
The most common surgical procedure for epilepsy is temporal lobectomy, which is performed when epilepsy occurs in the temporal lobe. Surgery is not as successful in epilepsies that occur in the frontal lobe and generally not recommended. It involves removing small portions from the hippocampus, a portion of the brain that is involved in memory processing and is part of the limbic system, an emotional center.
A typical case for this surgery is an adolescent or the adult woman with complex partial seizures that began between age five and 10. Although the seizures were often in remission, they eventually became intractable. Some women and children may be more difficult candidates because they often have injured areas outside the temporal lobes. Nevertheless, surgery can be very successful in many children, even if more than one area is involved.
Another most frequently used type of surgery for epilepsy aims to remove a seizure focus; a small area of abnormality in the brain where seizures originate. The operation removes the abnormal area of brain that is causing the epilepsy but leaves the parts that are still serving useful purposes. If the part of the brain causing the seizures is in the temporal lobe, the surgeon will perform a type of focal resection called a ‘temporal resection’. If the part of the brain causing the seizures is in one of the other lobes, then the operation will be called an “extra-temporal resection”.
A lobectomy or lobe removal takes away a larger area of the brain but is still intended to remove only the area of seizure focus. Temporal lobectomy is the most frequently performed surgical procedure to treat epilepsy. Removal of the temporal lobe stops temporal lobe epilepsy about 90% of the time.
Corpus callosotomy is considered for children who have many different seizure types, including ‘drop attacks’. Drop attacks occur when the child suddenly drops to the ground, either stiff or floppy and may harm themselves. This operation disconnects the two sides of the brain from each other but no tissue is removed. The aim of this procedure is to stop these ‘drop attacks’ but it will not affect the other seizure types.
This operation disconnects or removes one half of the brain from the other. Children who may benefit from this procedure usually have a long history of weakness down one side of the body. This is usually the result of severe damage to the opposite side of the brain, which may have been present from birth. The child’s general development may have been slow but normal. If the seizures are considered to arise from the damaged part of the brain, it is removed or disconnected to stop the seizures. This may not lead to any further weakness as the brain has usually reorganized other functions to the unaffected side.
WHAT EPILEPSY DIET IS SUGGESTED?
Exposure to toxic substances is one of the known causes of epilepsy. It is believed that a restricted caloric intake while on a balanced diet can lead to measurable seizure reduction among all age groups. Seizures have been treated by diet since ancient times. The earliest dietary treatment was fasting.
The diet used most frequently in modern times is very low in sugars and proteins and high in fat. The diet forces the body to burn fats for energy instead of sugars and is somewhat similar to currently popular weight-loss diets. It is known as the
ketogenic diet because burning fats is thought to increase ketones in the body, a condition called ketosis. Ketones are thought to prevent irritation of the central nervous system, that is, the spinal column and the brain.
The ketogenic diet should be used only under a doctor’s supervision, usually with the help of a dietitian.
The diet consists primarily of foods high in fat, with the remaining 25% to 35% of the calories made up of protein foods. Examples of high-fat foods include mayonnaise, butter, and cream. The child is allowed only small portions of cheese, meat, fish, or poultry each day. Fruit is allowed in modest amounts. There is an alternative source of fat, known as MCT, which is an oil. The use of the MCT allows a slightly greater expansion of non fat foods in the diet. However, some authorities find that MCT is not as beneficial in controlling seizures as other fat sources such as butter and cream.
WHAT PROCESS IS ADOPTED TO START KETOGENIC DIET?
In most cases, the diet is started while the child is in the hospital.
During the first 2 or 3 days, the child is not allowed to eat anything and is permitted to drink only a certain amount of water or other fluids. The child’s blood sugar level falls during this period of starvation.
If the fall in blood sugar is too great, the child may become pale, sweaty, tremorous, irritable, confused, and unresponsive, or even have seizures, and will need some sugar or other carbohydrate supplementation. The blood sugar level can be safely monitored in the hospital.
After several days of starvation, the ketones in the blood and urine rise, and the diet is gradually introduced. The urinary ketones can be easily measured at home by the parents, using an indicator strip. The presence of urinary ketones indicates that the diet has achieved its metabolic goal of ketosis.
If a child is taking high dosages of several antiepileptic drugs, tapering of one drug is often started during the period of starvation. Barbiturates are often discontinued first because they are the most sedative of the antiepileptic drugs; furthermore, their blood levels can rise when the diet is started even though the dosage is unchanged. If adequate ketosis is maintained, and seizure control improves, a further reduction in medications is often possible. In some cases, all medications can be tapered and stopped.
The ketogenic diet was first introduced in the 1920s but fell out of use after the introduction of antiepileptic drugs. It is currently being revived for treating children with severe seizures that do not respond to medications.
WHAT ARE THE RISKS OF A KETOGENIC DIET?
It is a very difficult diet to keep. The children are allowed to eat almost nothing but fat (butter, heavy cream) with very little meat and a limited range of low-sugar vegetables such as lettuce, celery, and cucumbers.
The most dangerous potential risk of the ketogenic diet is low blood sugar during the period of starvation.
Other potential problems include a deficiency of the B vitamins, vitamin C, and calcium. It is often wise to supplement these nutrients (making sure the supplement does not contain sugar).
High-fat diets in adults can accelerate atherosclerosis, which contributes to heart attacks, stroke, and other disorders of blood vessels. However, there is no evidence that the ketogenic diet accelerates atherosclerosis in children or adolescents. Unfortunately, we cannot be sure that the diet has no long-term effects on the blood vessels. Weight gain is not usually a problem on this diet.
The diet often causes nausea and diarrhea.
It can cause poor development from lack of nutrition.
It can also cause development of kidney stones from a build-up of uric acid in the system.
Use of the diet must be supervised by a doctor. The diet seems most effective in children under eight years old but it is occasionally helpful for adults. It has been shown to help 25% to 50% of children who have uncontrollable seizures.
HOW TO PREVENT EPILEPSY?
Epileptic seizures can be prevented by regular use of:
- Anti-seizure medication.
- Removal of brain tissue where seizures take place.
- Special diet to produce a change in body chemistry.
- Avoidance of special conditions known to trigger seizures in susceptible people.
- Adequate pre-natal and post-natal care.
- Safe delivery.
- Control of fever in children.
- Control of parasitic diseases.
- Prevention of brain injury.
- Controlling blood pressure.
- Using safety belts and helmets.
Drug therapy is by far the most often used and is almost always the method tried first. When taken regularly as prescribed, medication can prevent seizures in about half of all cases and produce improvement in about 30 percent of all cases. The remaining patients do not get much relief from existing medications.
When drugs fail to prevent seizures, surgery may be an option, but surgery is only possible when the seizures begin in one fairly small part of the brain that can be removed without affecting speech, memory or some other important brain function. Although surgery is not used as often as drug therapy, the results are similar – about 70 percent of all patients getting either fully or greatly improved control of seizures, and the rest have only a slight improvement or none at all.
Head injuries are responsible for many cases of epilepsy. The patient can reduce the risk by always wearing a seat belt while riding in a car and by wearing a helmet while bicycling, skiing, riding a motorcycle, or engaging in other activities with a high risk of head injury.
Stroke and other diseases that affect vascular system can lead to brain damage that may trigger epilepsy. A number of steps can be taken to reduce risk of these diseases, including limiting the woman’s intake of alcohol, following a healthy diet, managing the woman’s weight, exercising regularly and avoiding cigarettes.
In people with an active seizure disorder, it is also important to take precautions to minimize the risk of injury if a seizure should occur. For this reason, it is generally recommended that patients do not operate a motor vehicle or other dangerous machinery for at least six months following the most recent seizure.
People with epilepsy may find it helpful to wear a medical identification bracelet or other form of identification that describes their illness. This will provide vital information about their disease for medical professionals.