Epilepsy : Causes, Symptoms , Diagnosis and Treatment
Neurology / / May 03, 2016
Epilepsy - is a brain disorder and the presence of recurrent spontaneous seizures of any type.There are various types of epilepsy, but they all have recurring seizures caused by uncontrollable electrical discharge from the nerve cells in the cerebral cortex.This part of the brain controls the higher mental functions of the person, the general movement, the functions of the internal organs in the abdominal cavity, the perception of the functions and behavioral reactions.
brain structure includes: trunk, consisting of the spinal cord, medulla, pons and midbrain;cerebellum;brain (consists of two halves or two hemispheres);midbrain.
Seizures are a symptom of epilepsy.This episodes of disturbed brain function that cause changes in neuromuscular function, attention or behavior.They are caused by abnormal electrical signals in the brain.
The single attack may be linked to a specific medical problem (such as a brain tumor or a way out of the alcohol addiction).If the attacks are not repeated after that, an
first attack that can not be explained by any medical problem, has about 25% chance to return again.After the occurrence of a second attack occurs about 70% of the probability of future cases of epilepsy.
types of epilepsy
Epilepsy is usually divided into two main categories, depending on the type of seizures:
- partial (or focal, localized, focal) seizures. It fits, which are more common than generalized seizures, and born in one or more specific locations in the brain.In some cases, partial seizures can spread to wide regions of the brain.They may develop from specific injuries, but in most cases their exact origin is unknown (it is idiopathic - due to unknown cause or arose spontaneously, on their own, independently of the other defeats say about idiopathic epilepsy in cases where the basis of the clinical picture does not lie coarse anatomical changes.in the brain, as there is no reason to associate disease with stimuli from peripheral nerves, in contrast to symptomatic epilepsy that develops as a result of a variety of damage and disorders of the nervous system and often cerebral diseases - cranial trauma, dropsy of brain, inflammation of the meninges and of the cerebralbrain, etc.)..;
- Generalized seizures. These seizures usually occur in both brain hemispheres.Many forms of such seizures have a genetic basis.There is a regular, normal neurological function between episodes.Partial seizures, in turn, are divided into "simple" or "complex partial" ( "complex partial").
- Simple partial seizures. man with simple partial ( "Jacksonian") form of epilepsy does not lose consciousness, but it can be confusing thoughts, twitching, tingling or vague mental and emotional picture of events.Such events may include a "deja vu", light hallucinations, extreme answers to smell and taste.After an attack, the patient usually has a certain temporal muscle weakness.These seizures usually last for about 90 seconds;
- Complex partial seizures. More than half of seizures in adults - complex partial.About 80% of these seizures begin in the temporal lobe - a part of the brain, located close to the ear.Violations here can lead to loss of control over themselves, involuntary or uncontrolled behavior or even loss of consciousness.Patients may then be fixed and vacant look.Emotions may be exaggerated, but some patients may appear drunk.After a few seconds the patient can start to perform repetitive movements - such as chewing or smacking.Episodes usually last no more than two minutes.They may occur infrequently or frequently (every day).Complex partial spasm may follow a throbbing headache.
In some cases, simple or complex partial seizures developing into so-called secondary generalized seizures.Progression can be so fast that the initial partial seizures can not even notice.
Generalized (generalized) seizures are caused by disorders of nerve cells occurring in the common areas of the brain more than partial seizures.Thus, they have more serious consequences for the patient.They are still divided on the tonic-clonic (or grand mal), missing (small mal), myoclonic or atonic seizures.
- tonic-clonic (grand mal) seizures. first stage large epileptic seizure is called "tonic phase" - it muscles suddenly reduced, causing the patient falls down and is motionless for approximately 10-30 seconds.Some people have a premonition before the big epileptic attack.Most, however, lose consciousness without warning from the body.Throat or larynx may be high musical sound (stridor) when the patient inhales.The spasms last from about 30 seconds to 1 minute.Then the attack is included in the second phase, which is called "clonic".The muscles begin to relax then, then strain.After this phase, the patient may lose control of the bowel or bladder.An attack usually lasts a total of 2-3 minutes, after which the patient while still unconscious, then wakes up the confusion of thought and extreme fatigue.Severe throbbing headache similar to migraine can also follow tonic-clonic phase.
- Missing (small epileptic) seizures (petit mal). Missing or small seizures - brief loss of consciousness that occur within 3-30 seconds.Physical activity and attention loss can pause just for a moment.Such attacks may go unnoticed by others.Small children can walk or just watch idly.Small seizures can be mistaken for a simple or complex partial seizures or with attention deficit disorder (ADD or ADHD - addition to the diagnosis of all the stupid and inhibited adolescents persistent and chronic neurological syndrome that has not found a cure, neurological and behavioral developmental disorder., beginning in childhood is manifested by symptoms: difficulty concentrating, hyperactivity, impulsiveness poorly managed).For small seizures, however, a person may experience seizures often 50-100 times per day.
- Myoclonic seizures . Myoclonic seizures are a series of short jerky contractions of certain muscle groups - such as the face or body.
- Atonic (akinetic) seizures. A person who may be atonic (akinetic) seizure loses muscle tone.Sometimes it may affect only one part of the body - so that, for example, the jaw weakened and his head falls on his chest.In other cases, the entire body may lose muscle tone, and a person can suddenly fall.Brief atonic episodes known as "drop attacks".
- Simple tonic or clonic convulsions. Cramps can also be simple tonic or clonic.When muscles contract tonic convulsions, and state of mind is changing for about 10 seconds, but the attacks do not affect the clonic phase or twitching.Clonic seizures occur very rarely - mainly in infants who experience muscle spasms, but it - no tonic tension.
Epilepsy also grouped according to a set of common characteristics, including:
- age of the patient;
- type of seizures;
- behavior under attack;
- EEG results;
- the cause is known or not known (idiopathic).
Some inherited epilepsy syndromes are listed below;they do not represent all types of epilepsy.
- Temporal lobe epilepsy. Temporal lobe epilepsy is a form of partial (focal) epilepsy, although it can occur, and generalized tonic-clonic seizures.
- frontal lobe epilepsy. frontal lobe epilepsy is characterized by sudden violent attacks.Convulsions can also result in loss of muscle function, including - the ability to speak.Autosomal dominant nocturnal frontal form of epilepsy - a rare inherited form (seizures occur during sleep).
- «Western» Syndrome (infantile spasms). «Western" syndrome, also called "infantile spasms" - a disorder that involves spasms and delayed development in children during the first year of birth (usually in children aged 4-8 months).
- Benign familial neonatal convulsions (BFNC). Benign familial neonatal seizures are a rare hereditary form of generalized seizures that occur in infancy.BFNC, apparently due to genetic defects that affect the channels in nerve cells carrying potassium.
- Impulsive small seizures (IME impulsive or small epilepsy). IME is characterized by generalized seizures - usually tonic-clonic marked jerky movements (so-called myoclonic jerks), and sometimes absence seizures.It usually occurs in children and young adults (age - 8-20 years).
- Syndrome Lennox-Gastaut (PLGA, myoclonic-astatic epilepsy) - a combination, including atypical absence seizures, tonic seizures, atonic or astatic seizures, mental retardation and slow spikes and waves on the EEG with the onset of the disease at the age of 1-5years.The syndrome may develop as a result of many children's neurological diseases associated with poorly controlled seizures.With age, the beginning of the form and type of seizures often changes.In most cases, the attacks are replaced by fall on partial, complex partial or secondary generalized seizures.Usually - to the extent of mental retardation severe dementia, psycho-organic disorders, 80% - severe cognitive and personality disorders organic type, etc.Syndrome Lennox-Gastaut is a severe form of epilepsy, especially in young children, which gives them numerous attacks and some developmental delays.It usually involves missing, tonic and partial seizures.
- myoclonic-astatic epilepsy (MAE). MAE is a combination of myoclonic seizures and Astasia (decrease or loss of muscle coordination), which often leads to the inability to sit or stand without assistance.
- Progressive myoclonic epilepsy. progressive myoclonic epilepsy is a rare inherited disease and usually occurs in children aged 6-15 years.It usually includes a tonic-clonic seizures and significant sensitivity to light flashes.
- Landau-Kleffner syndrome. Landau Kleffner syndrome, is a rare epileptic condition which usually affects children aged 3-7 years.This leads to the loss of the ability to communicate through speech or writing (aphasia).
Status epilepticus (ES) is a serious, potentially life-threatening condition that requires immediate medical care.It can lead to permanent brain damage or death if not treated effectively attack.
ES looks like a recurring seizures that last more than 30 minutes and is interrupted only for short periods of partial exemption.Although any type of attack can be sustained or recurrent, the most serious form of status epilepticus is a generalized convulsive or tonic-clonic type.In some cases, status epilepticus is assigned to the first attack.
trigger (source, stimulus) EC is often unknown, but may include:
- failure to take antiepileptic drugs;
- Abrupt withdrawal of certain anti-epileptic drugs - in particular, barbiturates and benzodiazepines;
- high body temperature;
- electrolyte imbalance (imbalance of calcium, sodium and potassium);
- heart failure;
- low blood sugar levels in people with diabetes;
- infection of the central nervous system (CNS);
- a brain tumor;
- drinking alcohol.
attack may be associated with temporary terms and conditions listed below.If the attacks did not recur after the main problem has been corrected, the person does not suffer from epilepsy.
Conditions associated with epileptic seizures include:
- brain tumors in children and adults;
- other structural lesions of the brain (eg, stroke);
- brain injury, stroke, or transient ischemic attack (TIA);
- cessation of alcohol after a heavy binge for days;
- diseases that cause deterioration of state of the brain;
- problems that are present before a person's birth (congenital brain defects);
- brain injuries that occur during childbirth or during birth;
- low blood sugar, low sodium levels in the blood or calcium or magnesium imbalance;
- renal or hepatic impairment;
- infection (brain abscess, meningitis, encephalitis, neurosyphilis, or HIV / AIDS);
- the use of cocaine, amphetamines (CNS stimulant phenylethylamine derivatives) or certain other recreational drugs;
- medicines - such as theophylline, meperidine, tricyclic antidepressants, phenothiazines, lidocaine, quinolones (a group of synthetic antibacterial agents, including fluoroquinolones exert bactericidal action), penicillins (anti-microbial agents lactam antibiotics class?), Selective serotonin reuptake inhibitor (SSRIs - pharmacotherapeutic group of the third generation of antidepressants for the treatment of anxiety disorders and depression), isoniazid (a drug anti-TB drug), antihistamines (group of drugs, carrying out histamine receptor blockade in the body), Tacrolimus (strong immunosuppressant selectively acting on the Tlymphocytes), interferons (a generic name for a number of proteins with similar properties allocated cells of the organism in response to the invading virus; interferons due cells become refractory to the virus), and lithium;
- discontinuation of certain drugs - such as barbiturates (a group of medicines, barbituric acid derivatives that have a depressant effect on the central nervous system), benzodiazepines (a group of psychoactive substances with sedative, hypnotic, muscle relaxant, anxiolytic and anticonvulsant effects; effects associated with exposure toreceptors) and some antidepressants after receiving them over a certain period;
- prolonged exposure to certain chemicals (such as lead, carbon monoxide);
- Down syndrome (trisomy for chromosome 21, one of the forms of genomic pathology, in which the most represented karyotype 47 chromosomes instead of the normal 46) and other developmental defects;
- phenylketonuria (PKU - a serious hereditary genetic metabolic disease, characterized mainly damage to the nervous system, can cause seizures in infants);
- seizures, febrile seizures in children, caused by high temperatures.Most febrile seizures in young children is between the ages of 9 months to 5 years.Simple febrile seizures (convulsive seizures at body temperature above 38 ° C) lasts less than 15 minutes and only in cases where the temperature is kept for 24 hours.This is typically an isolated event, and not the main feature of epilepsy.