Epilepsy |
What is Seizure?
A seizure is a temporary disturbance in brain function in which groups of nerve cells in the brain signal excessively. Seizures may produce changes in awareness or sensation, involuntary movements, or other changes in behavior. Usually, a seizure lasts from a few seconds to a few minutes. Recurrent seizure is called epilepsy.
What are seizures?
There are many types of seizures. These can be classified into two broad groups: |
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- Primary generalized seizures—seizures begin with widespread involvement of both sides of the brain.
- Partial seizures—seizures begin with involvement of a smaller, localized area of the brain.
- Some people have seizures that are hardly noticeable to others. Sometimes, the only clue that a person is having an absence seizure is rapid blinking or a few seconds of staring into space. In contrast, a person having a complex partial seizure may appear confused or dazed and will not be able to respond to questions or direction for up to a few minutes. Finally, a person having a generalized tonic-clonic seizure, may cry out, lose consciousness, fall to the ground, and have rigidity and muscle jerks lasting up to a few minutes, with an extended period of confusion and fatigue afterward.
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What is the burden of epilepsy in India?
Incidence of epilepsy in the world varies from 0.5 to 2 % in once life time. In India about 10 million people suffer from epilepsy that means one in hundred people will develop seizure in their life time.
What causes epilepsy?
Epilepsy may arise when there are disruptions to the normal connections between nerve cells in the brain (much like disruptions in wiring of a complex electrical circuit), when there are imbalances of natural chemicals or neurotransmitters that are important to the signaling among nerve cells, or when there are changes in the membranes of nerve cells, including proteins called ion channels, that alter their normal sensitivity. Some of these disruptions, imbalances, and changes may develop early in life, sometimes related to hereditary factors and sometimes related to early exposures and events. Others may be acquired later. Among known conditions and events that may lead to epilepsy are: |
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- Oxygen deprivation (e.g., during childbirth).
- Brain infections (e.g., meningitis, encephalitis, cysticercosis, or brain abscess).
- Traumatic brain injury or head injury.
- Stroke (resulting from a block or rupture of a blood vessel in the brain).
- Brain tumors.
- Certain genetic disorders.
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In nearly two-thirds of the cases of epilepsy, a specific underlying cause is not identified. In these instances, the cause may be labeled cryptogenic if the cause is unknown, or idiopathic if the epilepsy is not associated with other neurologic disease but is consistent with certain syndromes that may be inherited.
What investigations are done for epilepsy?
The diagnosis of epilepsy is entirely based on the description of an attack by a witness. The specific investigations include EEG & imaging investigation like CT Scan or MRI scans are done.
What is an EEG?
Electroencephalograph is a record of brain electrical activity (EEG) - like ECG is a record of heart electrical activity. Epilepsy being a result of burst of abnormal electrical discharges. EEG will help to detect such abnormal electrical discharges. EEG can also detect from which part of the brain the electrical discharges originate.
How does EEG help in the diagnosis of epilepsy?
EEG is not for diagnosis of epilepsy but to know the type of epilepsy, so that appropriate antiepileptic drug can be chosen.
What is Computerized Tomography (CT Scan)?
The CT scan is a type of imaging of the brain wherein through x-rays it detects any structural abnormality of the brain responsible for causing epilepsy e.g. brain tumor, brain TB. However as epilepsy, in a large number of people, is due to no known cause CT will be normal.
What is MR Scan (Magnetic resonance imaging) (MRI)?
MRI is an advanced method of imaging of the brain which can detect structural abnormality that are likely to be missed by CT scan. In particular MR scan is very useful in identifying small scars in the brain responsible for epilepsy and help in selecting patients with epilepsy for surgical treatment.
How is epilepsy treated?
Before a person begins treatment, the first step is to ensure that the diagnosis of epilepsy is correct and to determine, if possible, the type of epilepsy and whether there are any underlying conditions that also need treatment. This will require a careful review of the person's medical history and a neurological examination. Other tests may be recommended as well, usually including an electroencephalogram (EEG) and often a brain scan such as computed tomography (CT) or magnetic resonance imaging (MRI). The medical decision about how best to treat the epilepsy is based on this evaluation. |
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- Antiepileptic drugs are the mainstay of treatment for most people. There are now many drugs available, and a doctor may recommend one or more of these based on several individual patient factors such as the type of epilepsy, the frequency and severity of the seizures, age, and related health conditions. After starting a medication, close monitoring is required for awhile to assess the effectiveness of the drug as well as possible side effects. Early in treatment, adjustments in dosage are often required. Sometimes, because of continued seizures or significant side effects, it is necessary to change to a different drug. For about two-thirds of people with epilepsy receiving optimum treatment, drugs are successful in fully controlling seizures. For the remainder, although drugs may have a partial benefit, some seizures continue to occur. For some of these people, other treatment options may be considered.
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- Surgery. With certain types of partial epilepsy, especially when it can be determined that seizures consistently arise from a single area of the brain (the "seizure focus"), surgery to remove that focus may be effective in stopping future seizures or making them much easier to control with medication. Epilepsy surgery is most commonly performed when a seizure focus is located within the temporal lobe of the brain.
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- Other options. Other supplemental treatments are sometimes beneficial when medications alone are inadequate and surgery is not possible. These include vagus nerve stimulation, where an electrical device is implanted to intermittently stimulate a large nerve in the neck, and the ketogenic diet, a high fat, low carbohydrate diet with restricted calories.
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What issues are unique for women with epilepsy?
Women with epilepsy can experience difficulties arising from hormonal changes during their reproductive cycle that sometimes can affect the tendency to have seizures. Pregnancy brings some special considerations for women with epilepsy, because seizure occurrence and certain drugs taken during this time may sometimes carry a risk of harm to the developing fetus. Usually these risks can be minimized by several precautions women can take before and during pregnancy.
Are people with epilepsy permitted to drive vehicles ?
Ans: As per the Motor vehicle Act in India - driving is not permitted once a person declares that he had / has epilepsy or even if he is free from epilepsy and off medication. In the western countries driving is allowed to drive personal vehicle if a person is free from seizures for 6 months - 2 years even while taking antiepileptic drugs (AEDs).
Can epilepsy be prevented?
Sometimes epilepsy may be preventable. Considering the causes of epilepsy listed previously, there are several opportunities for prevention. Some of the most important are: |
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- Complications of pregnancy and childbirth. Proper prenatal care to avoid problems during pregnancy and childbirth may lessen complications that could lead to epilepsy.
Infections. Proper immunization (vaccination) against certain diseases of childhood and adolescence or young adulthood may lessen the likelihood of infections that can sometimes involve the central nervous system and lead to epilepsy.
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- Cysticercosis can be prevented through public health screening and early treatment as well as proper practices of hygiene and food preparation.
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- Traumatic brain injuries. Brain injuries, often due to motor vehicle crashes or falls, are a frequent cause of epilepsy.
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- There are effective ways to reduce the occurrence and severity of motor vehicle and traffic injuries: consistently using safety belts, airbags, and motorcycle helmets.
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- Stroke . Reducing or treating risk factors such as physical inactivity, high blood pressure, obesity, diabetes, high cholesterol, and smoking will lessen the likelihood of stroke and heart disease, which may help to reduce the possibility of developing epilepsy later in life.
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