Epilepsy introduction
Epileptic seizures are sudden, often
dramatic, "electrical storms" in the brain that range from very brief periods of
"blanking out" to full-blown convulsions.
The term epilepsy is used when
seizures are recurrent over an extended period of time.
A detailed description of the seizure,
a neurological examination, and a variety of specialised tests help the
physician distinguish seizures from other kinds of brain attack, allow for
classification, and may reveal an underlying cause.
Modern
treatment has become highly effective, allowing most epileptics to lead
productive, healthy lives.
Epilepsy
Epilepsy is a situation that causes anyone to have repeated fits. The medical
time period for an epileptic match is seizure.
Round one in each 280 youngsters is affected by
epilepsy.
Seizures
The cells within the mind, often known as neurons, talk with each other by
utilizing electrical impulses. Throughout a seizure, the electrical impulses are
disrupted, which may cause both the brain and the physique to behave strangely.
The severity of the seizures can differ from person to person. Some individuals
will simply expertise a ‘trance-like’ state for a couple of seconds, or minutes,
whereas others will lose consciousness and have convulsions (uncontrollable
shaking of the physique).
What is
epilepsy?
Epileptic seizures are sudden, often dramatic "electrical storms" in
the brain that affect about 0.5% of the population. All may be seen as symptoms
of a wide variety of underlying disorders of brain or body that promote seizure
activity.
There
are several different seizure types. Some seizures cause convulsions with loss
of consciousness and violent muscle spasms, while others may involve unusual
sensations, brief periods of "blanking out" or manifest simply as altered
behavior. The term epilepsy is used when seizures are recurrent over an extended
time period.
The
following examples describe two quite different settings in which seizures may
occur: A solitary seizure associated with alcohol withdrawal is best thought of
as an isolated seizure with a clearly defined cause, whereas a child with
developmental delay and recurrent seizures as a result of birth injury to the
brain should be regarded as having epilepsy.
Epileptics are frequently stigmatised by others for their disease, and it should
be emphasized that the tendency to have seizures is quite distinct from mental
retardation or low intelligence. Although seizures are usually not
life-threatening in themselves, the consequences of seizing (e.g. while driving
or swimming) may be fatal. Convulsive seizures are frightening events to
experience either directly or as an onlooker. Knowing something about seizures
and the ways in which they can be managed is a first step towards taking
control.
What
causes epilepsy?
A seizure is best thought of as an uncontrolled, abnormal burst of
electrical and chemical activity that spreads rapidly between nerve cells
(millions upon millions of them) in the brain. A seizure may start in one region
of the brain (the "focus") and spread to other parts. The first symptoms of a
seizure, referred to as the "aura" (often a strange sensation or smell) reflect
the function of that part of the brain first affected by the epileptic activity.
A seizure that initially causes only twitching of one hand and then goes on to
convulsions with loss of consciousness, for example, reflects seizure activity
that starts in the front part of one hemisphere and then spreads to involve
widespread areas on both sides of the brain.
Seizures
are a feature of a variety of states of ill-health, and have many differing
causes. Seizures may be the only manifestation of disease, may be caused by a
specific brain disorder, or are seen as part of a more generalised bodily
illness.
Primary
epilepsy refers to seizures, often seen in children, where the brain is
abnormally prone to seizure activity. Secondary seizures, on the other hand, are
the result of specific, identifiable causes. Seizures may cease if the
underlying condition is treated and in this sense, seizures may be regarded as
symptoms of the underlying condition. Meningitis and other infections, strokes,
head injury, brain surgery, drug and alcohol abuse, brain tumours and fever are
among the many causes of seizures. In a significant proportion of patients,
however, no cause can be identified.
In all
forms of epilepsy, stress, sleep deprivation, a change in diet or medication,
alcohol, certain specific activities, and menstruation and pregnancy in women
may precipitate individual seizures.
Symptoms
and signs of epilepsy
Symptoms of epilepsy
The main symptoms of epilepsy are repeated seizures.
Docs who deal with epilepsy classify seizures by how much of the mind is
affected. There are:
-
partial seizures - the place only a small part of the mind is affected, and
-
generalised seizures - the place most or the entire brain is affected.
Partial seizures
There are two kinds of partial seizure:
-
simple partial seizure - it is a seizure the place you remain acutely aware, and
-
complicated partial seizure - it is a seizure where you lose your sense of
consciousness and may have no reminiscence of the event.
Signs of a simple partial seizure include:
-
experiencing adjustments in the best way issues look, smell, really feel, taste
or sound,
-
experiencing an intense feeling of déjà vu (a sense that these events have
occurred before),
-
experiencing a tingling sensation (‘pins and needles’) in your arms and legs
-
experiencing a sudden intense emotion, such as worry or joy,
-
the muscle tissues in your arms, legs and face could develop into stiff, and
-
you may experience twitching on one side of your body.
The symptoms of a posh partial seizure are usually characterised by apparently
unusual and random bodily behaviour, resembling:
-
smacking your lips,
-
rubbing your palms,
-
making random noises,
-
transferring your arms round,
-
choosing at garments,
-
twiddling with objects,
-
adopting an unusual posture, and
-
chewing, or swallowing.
Throughout a fancy partial seizure, you won't be able to answer anyone else, and
you will have no reminiscence of the event.
Complex partial seizures are fairly frequent, accounting for 2 in 10 of all
seizures experienced by individuals dwelling with epilepsy.
Generalised seizures
Generally an individual having a generalised seizure will be completely
unconscious.
There are six fundamental varieties of generalised seizure, that are described
below.
Absences
Absences (also known as petit mal seizures) are seizure that mainly affects
children. They trigger the child to lose awareness of their surroundings for
five to 20 seconds. The kid will seem to only stare vacantly into house,
although some kids will flutter their eyes or smack their lips. The kid will
have no reminiscence of the seizure.
Absences can occur a number of instances a day. Though they don't seem to be
harmful, they may affect the child's performance at school.
Myoclonic jerks
Some of these seizures trigger your arms, legs or upper body to jerk or twitch -
very like if in case you have obtained an electrical shock. They typically
solely final for a fraction of a second, and it is best to remain aware
throughout this time.
Myoclonic jerks often occur within the first few hours after waking up and might
occur together with other sorts of generalised seizures.
Clonic seizure
This causes the same kind of twitching as myclonic jerks, except the signs will
last more, usually up to two minutes. Loss of consciousness may occur.
Atonic seizure
This causes your entire muscle tissues to abruptly relax, so there's a
probability you'll fall to the bottom and facial injuires are common with this
sort of seizure.
Tonic seizure
In contrast to an atonic seizure, this causes the entire muscle tissues to all
of a sudden become stiff and you'll then lose balance and fall over, so injuries
to the back of the head are common with any such seizure.
Tonic clonic seizure
A tonic colic seizure (also referred to as a grand mal seizure) has two stages.
Your physique will change into stiff after which your arms and legs will start
twitching. You'll lose consciousness and a few people will moist themselves. The
seizure usually lasts between one and three minutes however they can last
longer.
That is the commonest type of seizure, accounting for 60% of all seizures
skilled by individuals dwelling with epilepsy.
Tonic-colic seizure are usually what individuals are referring to when the use
the time period ‘epileptic match'.
Folks can expertise any of the above types of seizure, however usually the
pattern of any individual's signs remains the same. This pattern is named an
epilepsy syndrome.
Auras
People who have epilepsy usually get a particular feeling or warning signal that
a seizure is on its way. These warning signs are generally known as auras.
Auras differ from person to person, however some frequent auras embrace:
-
noticing a strange odor or taste,
-
having a feeling of déjà vu,
-
feeling that the outside world has instantly grow to be unreal or dreamlike,
-
experiencing a sense of worry or anxiety, and
-
your body all of a sudden feels strange.
Generalised seizures
Generalised seizures are those that cause loss of consciousness, and
imply widespread involvement of both hemispheres of the brain.
Generalised tonic-clonic seizures,
previously termed "grand mal" seizures, are the most dramatic and frightening
kind of seizure. Sudden collapse with loss of consciousness is followed by
muscle spasm ("tonic") and violent jerking ("clonic") of the limbs that builds
to a climax and then subsides and stops on its own after several minutes. The
involuntary contraction of muscles can cause tongue biting, temporary arrest of
breathing, and incontinence. Injury may occur in falling to the ground and as a
result of the violent movements of the limbs. Exhaustion, muscle aches and
headache are common for several hours after the seizure has settled, in the
so-called "post-ictal" period.
Absence seizures ("petit
mal") also involve loss of consciousness, and as such are also generalised
seizures, but are quite distinct from tonic-clonic convulsions. Seen most
frequently in children, absences involve very brief periods (seconds) of
"blanking out" that may occur many times a day, and are often put down to
daydreaming. These staring spells briefly interrupt whatever the child is doing
and may be associated with fidgeting or picking at clothes (automatisms). The
child and his or her family may be quite unaware of anything unusual, and
absence seizures frequently only come to light when schoolwork suffers.
Other
varieties of generalised seizure may involve sudden loss of muscle tone with
collapse or large-scale jerks of the whole body, but these are rare.
How is
epilepsy diagnosed?
Obtaining a clear description of the seizure either from the patient
themselves, or more often from reliable eyewitnesses, is the initial and most
important step in diagnosing an epileptic seizure. The physician needs to
recognise features that suggest a seizure and distinguish it from other kinds of
brief neurological events. These include TIAs (transient ischaemic attacks –
"mini-strokes"), fainting spells, behavioral problems and a range of involuntary
movements. Seizures are characterised by the presence of an aura, rhythmical
jerking, alteration or loss of consciousness, and a post-ictal period of
recovery. A careful history may also provide clues to finding a cause for
seizures, such as a head injury or alcohol or drug addiction.
Usually
patients have no signs of epilepsy or ill-health between seizures, and a
physical examination may be quite normal. In some patients, signs of
neurological disease may point towards a cause for the seizures.
An
electroencephalogram (EEG) is a recording of the brain's electrical activity as
measured by electrodes stuck on the outside of the scalp. A recording made
during the normal interval between seizures in an epileptic often reveals a
seizure "signature" – spiky waves on the smooth, regular background pattern of
normal brain waves – and can provide important information about the type and
location of the seizure. A normal EEG does not rule out the diagnosis of
epilepsy, however. During a seizure, abnormal activity tends to be clearly
evident on the EEG recording. Certain patients may be admitted to an epilepsy
unit for long-term monitoring. Here, a video recording of the patient asleep and
awake and an EEG tracing are obtained over many hours, and the two can be
compared side by side.
Other
investigations, including various blood tests, and CT or MRI scans of the brain
help to determine a cause, and are often obtained as part of the workup of a
first seizure.
How is
epilepsy treated?
Many seizures are the direct result of an underlying brain or bodily
disorder. In such a case, treatment of the underlying condition will often be
sufficient to prevent seizures from recurring, and the seizures themselves will
need no specific management. In general, seizures that have only occurred once
are not treated unless they recur. Once seizures are recurrent, specific
anti-epileptic medication will generally be needed. Some epileptics will only
have seizures in certain settings, or find that their seizures are reliably
provoked by specific triggers. Alcohol use and sleep deprivation are frequently
responsible.
There
has recently been an explosion of new drugs for treating epilepsy. These
new-generation medications are better tolerated, are somewhat more efficacious,
and are all considerably more expensive than the older medications, which remain
the mainstay of treatment. Examples of widely-used established medications are
Carbamazepine, Phenytoin, Phenobarbital, Valproic acid and Ethosuximide.
Examples of newer medications are Levetiracetam, Lamotrigine, Topiratmate and
Gabapentin. Choosing the best agent is a complex task best done by a neurologist
with a special interest in epilepsy. The choice will rest on the type of
seizure, as well as the efficacy of the medication and how well it is tolerated
by the individual patient. All medications have side-effects, need to be taken
regularly, and must be monitored carefully. Most patients are rendered
seizure-free with the use of a single medication, or, if necessary, medications
in various combinations.
Follow-up should occur at least annually. Monitoring drug levels in the blood is
important for continued control of seizures and reduction of side-effects.
Illness, pregnancy, sleep deprivation, skipping medication doses and using
drugs, alcohol or certain medications may cause seizures in someone with
previously well-controlled epilepsy. People with epilepsy should wear
Medic-Alert bracelets, and family members should be instructed in how to assist
during a seizure.
The last
decade has seen the development of effective surgery for seizures of certain
kinds. In general, surgery is reserved for patients with a seizure focus that
can be precisely identified, and who have failed drug therapy. Workup for
surgery is complex, but when successful, surgery may render patients
seizure-free without having to use medications. Other modalities of treatment,
such as the vagal nerve stimulator, are also used in specific cases.
Emergency first-aid treatment for a convulsive seizure
At
the onset of the seizure, before the tonic phase begins, it is appropriate for
an experienced person to insert an oral airway, padded tongue blade or other
soft object between the teeth. Don't try to force a hard object between the
teeth once the jaws are closed, as the teeth or object may break and fragments
may be inhaled.
Protect
the person from injury. Clear the area of furniture or other objects that may
cause injury. Cradle the head with a pillow if it is on a hard surface, but
don't restrain the person's movements.
Turn the person onto one side with the
head down. This allows drainage of saliva and prevents inhalation of vomit.
The vast majority of seizures will end
spontaneously after a minute or two, and no specific treatment is necessary.
When seizures continue, or consciousness is not regained between seizures,
status epilepticus is diagnosed and requires urgent management that may be
started by the emergency medical service, but is best performed in a hospital.
What is
the outcome of epilepsy?
Although epilepsy tends to be a lifelong condition, effective
management is available for most, allowing a seizure-free, productive life. Most
occupations and recreational activities are open to people with controlled
epilepsy, and most countries allow driving after a seizure-free period of 6-12
months (on or off medication).
Complications of seizures can occur in many forms. Although seizures themselves
tend to be self-limiting, the consequences of abruptly losing contact with the
environment can be dangerous. These include: accidents while driving, bathing,
swimming or using machinery; injuries sustained from falling or trauma to
flailing limbs; and aspiration of vomit, leading to choking or aspiration
pneumonia.
Status
epilepticus refers to seizures that do not stop, or are so close together that
consciousness is not regained. In this serious circumstance, respiratory and
metabolic failure occurs, and mortality is high, even with intensive care
treatment.
Even
when seizures do not directly threaten life or limb, the condition can be
damaging. If absence seizures are not recognized in children, these brief
interruptions of attention throughout the day can lead to learning disability.
Older children and adults may find the prospect of seizures so socially
embarrassing or frightening that they withdraw from the world. Explanation of
the condition, the broader education of the public, and contact with other
people affected by seizures can do much to alleviate this.
Lastly,
all anti-epileptic drugs have side-effects, and in an individual patient this
often governs the choice of agent. Most of these side-effects are reversible and
simply represent individual intolerance to a particular medication or
excessively high dose. Rarely, side-effects can be unpredictable and serious.
Pregnant women need especially careful choice of medication, and younger women
who may fall pregnant need effective contraceptive advice.
Can
epilepsy be prevented?
If seizures occur as the result of an underlying disease of the brain
(e.g. a tumour) or the body (e.g. kidney failure), treatment of these primary
conditions can prevent seizures from occurring, and anti-epileptic medication
may become unnecessary. In other circumstances, drug treatment or surgery for
epilepsy can prevent seizures from recurring. Occasionally, drug therapy is
prescribed prophylactically – as is the case after brain surgery, where a short
course of anti-epileptic medication is often prescribed routinely to all
patients, even those with no history of seizures.
In
established epilepsy, avoiding changes in routine, disturbed sleep, drugs and
alcohol, and (in a minority of patients) certain situations or activities known
to promote seizures, are other practical forms of prevention.
When to
call the doctor
Seizures in anyone other than in those with recognized, regular
seizures is cause for concern, and medical advice should follow. This is
especially true in the case of a first seizure where the cause needs
investigation. In most cases, the seizure will be over by the time the patient
sees a doctor, so it is important for eyewitnesses to describe what happened.
Status
epilepticus is a medical emergency and the relevant services should be contacted
without delay.
In
established patients on anti-epileptic medication, contact with your doctor may
be necessary if you suspect that the medication is making you feel unwell. This
is particularly likely when a new drug has been started, dosage altered, or if
any other medications are taken as these may interact with the antiepileptic
drugs.
