Seizures and Epilepsy Syndrome

Introduction to seizures and epilepsy syndrome Epilepsy is a chronic recurrent transient brain dysfunction syndrome characterized by recurrent epileptic seizures caused by abnormal discharge of brain neurons. It is a common cause of episodes of loss of consciousness. Epilepsy is not a group of diseases or Syndrome. The term epilepsy comes from ancient Greek, referring to clinical recurrent limb tics or convulsions. In the 38 years before the emergence of EEG techniques, Jackson (1886) proposed that epilepsy is a highly unstable brain cell population suddenly temporarily over-discharged. "caused. German psychiatrist Hens Berger (1924) first recorded EEG activity on the human scalp, proving the definition of epilepsy that Jackson predicted. basic knowledge The proportion of illness: 0.03% Susceptible people: no special people Mode of infection: non-infectious Complications: traumatic epilepsy, traumatic asphyxia

Seizures and causes of epilepsy syndrome

The etiology of epilepsy is extremely complex and can be divided into four categories, and there are many factors that affect the onset of the disease.

1. Idiopathic epilepsy and epilepsy syndrome

There is no other obvious cause of suspicious genetic predisposition. It often starts in a certain age group, has characteristic clinical and EEG performance, and the diagnostic criteria are clear.

2. Symptomatic epilepsy and epilepsy syndrome

It is a well-defined or possible central nervous system disorder that affects structures or functions, such as chromosomal abnormalities, focal or diffuse brain diseases, and certain systemic diseases.

3. cryptogenic

Epilepsy is more common in clinical manifestations suggesting symptomatic epilepsy, but no clear cause can be found, which can occur in a particular age group without specific clinical and EEG performance.

4. State-related seizures (situationrelatedepilepticattack)

Attacks are related to special conditions, such as high fever, hypoxia, endocrine changes, electrolyte imbalance, drug overdose, long-term drinking withdrawal from sleep deprivation and excessive drinking water. Normal people may also have epileptic seizures, but remove the relevant state. It does not happen anymore, so it does not diagnose epilepsy.

Seizures and prevention of epilepsy syndrome

Prevention of epilepsy is very important. Prevention of epilepsy is not only related to the medical field, but also related to the whole society. Prevention of epilepsy should focus on three levels: one is to focus on the cause and prevent the occurrence of epilepsy; the second is to control the seizure; the third is to reduce epilepsy. The physical, psychological and social adverse effects of the patient.

1. Prevent the occurrence of epilepsy

Genetic factors make certain children convulsive and produce seizures under the trigger of various environmental factors. To this end, special emphasis should be placed on the importance of genetic counseling. Family surveys should be conducted in detail to understand patients' parents, siblings and close relatives. Whether there are seizures and their seizure characteristics, for some serious hereditary diseases that can cause mental retardation and epilepsy, prenatal diagnosis or neonatal screening should be carried out to decide to terminate pregnancy or early treatment.

For secondary epilepsy should prevent its specific cause, prenatal attention to maternal health, reduce infection, nutritional deficiencies and various systemic diseases, so that the fetus is less adversely affected, prevent birth accidents, neonatal birth injury is an important cause of epileptic seizure One of them, avoiding birth injury is of great significance in preventing epilepsy. If you can regularly check pregnant women, implement new methods, and deal with dystocia in time, you can avoid or reduce the birth injury of newborns, and pay enough attention to the febrile seizures in infants and young children. Try to avoid seizures, and should be controlled immediately when the attack occurs. It is necessary to actively prevent various diseases of the central nervous system in children, timely treatment, and reduce sequelae.

2. Control the onset

Mainly to avoid the predisposing factors of epilepsy and comprehensive treatment to control the onset of epilepsy, statistics show that after the first seizure, the patient's recurrence rate is 27% to 82%, it seems that most patients after a single episode It will recur, so it is especially important to prevent the recurrence of epileptic symptoms.

3. Reduce the sequelae of epilepsy

Epilepsy is a chronic disease that can last for years, even decades, and can have serious adverse effects on the patient's body, mind, marriage, and socioeconomic status, especially deep-rooted social prejudice and public discrimination. Attitude, patient's misfortunes and frustrations in family relations, school education and employment, restrictions on cultural and sports activities, etc., can not only cause disgrace and pessimism, but also seriously affect the patient's physical and mental development, and will disturb the patient's family, teachers , doctors and nurses, and even the society itself, so many scholars have emphasized that the prevention of sequelae of epilepsy is as important as the prevention of the disease itself. The sequela of epilepsy is both the patient's body and the whole society, which requires society. All walks of life to understand and support patients with epilepsy, to minimize the social sequelae of epilepsy.

Seizures and complications of epilepsy syndrome Complications traumatic epilepsy traumatic asphyxia

It is currently believed that epileptic disease is a clear pathological state caused by a single specific cause, not just the type of seizure. Epileptic encephalopathy is an epileptic discharge that causes progressive brain dysfunction. Therefore, different causes And the brain dysfunction caused by the attack is different, the clinical complications are also different, but the common point is that there may be accidents such as trauma or asphyxia caused by the attack.

Seizures and symptoms of epilepsy syndrome Common symptoms convulsions, convulsions, muscles, meningitis, frequent ridicule, single sputum, automatic disease, neuronal migration, abnormal frontal lobe epilepsy, sputum area, frontal lobe epilepsy, island episode

The symptoms of epilepsy are diverse, and most patients are completely asymptomatic and physical signs during the interictal period; epilepsy with special causes may have symptoms and signs of primary disease. The following are only the typical symptoms of different types of seizures.

1. Tonic-clonic seizures: Tonic-clonic seizures, also known as large seizures, refer to the onset of systemic muscle twitching and loss of consciousness. According to the international seizure classification criteria, the discharge range starts from bilateral syncy to the whole brain, without limitation. Sexual discharge, mainly refers to primary epilepsy, the cause is more complicated, 75% to 80% of patients can not find the exact cause, in the known cause, birth injury, brain trauma, brain tumors, etc. are more common, it is now recognized The incidence of convulsions and abnormal EEG in the parents and siblings of the patients is significantly higher than that of normal people. It may be autosomal dominant, accompanied by incomplete penetrance, or may be a defect in the brain's certain biochemical metabolism. As a result, this type of epilepsy can be induced by flash, sound stimulation, overwork, overeating, hunger, mood swings, infection, surgery and other factors can aggravate seizures, menarche and menstrual period have a tendency to aggravate seizures, which may be related to menstrual progesterone Related to the reduction, progesterone has an anticonvulsant effect, and may also be related to changes in the distribution of water inside and outside the menstrual brain cells.

The tonic-clonic seizure can occur at any age, and there is no significant difference between men and women. It is the most common type of seizures in various epilepsy. The typical seizures can be divided into four clinical stages: the aura, the tonic phase, the clonic phase, and the recovery phase.

During the episode, the EEG is a typical combination of explosive multi-spindle waves and spine-slow waves. Each time the spine slow wave synthesis can be accompanied by muscle beats.

2. Partial seizures: Simple partial seizures refer to the symptoms of the local cortical discharge of the brain that correspond to the function of the part, including exercise, sensation, autonomic nerves, mental symptoms and signs. These symptoms can also occur in complex parts. The main difference in seizures (psychomotor episodes) is that the latter is accompanied by a disturbance of consciousness.

Simple partial seizures are symptoms of hemispheric damage. About 50% of patients have abnormal CT scans. The damage can be either static or progressive. In large case analysis, the mid-term complications of the cause account for about 25%. Others are trauma, tumor and sequelae of intracranial infection, etc., different ages, the cause of the difference is also large, in infants and children, the main period of injury, in the elderly, you should pay attention to exclude tumors and cerebrovascular accidents .

Regardless of the etiology and pathophysiological process, the onset performance depends on the location and function of the cortical lesions, and can be divided into four groups:

1 with symptoms of exercise;

2 with physical or special sensory symptoms;

3 with autonomic symptoms and signs;

4 with mental symptoms.

3. Complex part of the episode: complex part of the seizure habit is also called psychomotor seizure, compared with partial seizures with simple symptoms, accompanied by consciousness disorder is its main feature, the disturbance of consciousness can be preceded or later than the symptoms and signs of simple partial seizures, In addition to disturbances of consciousness, it can be manifested not only in other manifestations, but also in the form of autonomic syndromes. The various forms of clinically complicated partial seizures are often mixed together, which poses certain difficulties for diagnosis and treatment.

Specimens from patients with complex partial seizures who have undergone surgical resection of the temporal lobe have demonstrated that in about 50% of patients, tendon sclerosis, loss of nerve cells in the hippocampus, changes in fibroblasts, gliosis or atrophy, in addition to the marginal system of the temporal lobe Localized lesions, such as meningeal scars, remnants of contusions or abscesses, vascular abnormalities, gliomas, hamartomas, tuberous sclerosis, etc., of which gliomas are the most, some brain tissue is abnormally mild or no histological changes About 25% of patients with CT scans can show local abnormalities, especially in those patients whose onset age is over 30 years, and there are more local CT abnormalities.

There is no significant gender difference in this type of attack. The onset age is later in each type of epilepsy. About 50% of patients have aura, most often as fear; the abdomen has abnormal sensation of sensation, numbness and visual impairment, etc. It occurs when loss of consciousness occurs or is about to be lost, so the patient can still recall after the attack.

4. Absence of seizures: Absence of seizures, also known as small seizures, is typically characterized by transient disturbances of consciousness, without symptoms of aura or post-onset. For a long time, people will have atypical absence of seizures, myoclonic seizures, and tension-free episodes. Partial seizures are collectively referred to as minor episodes, and most scholars now no longer use the term episode to avoid confusion with seizures.

For a long time, people have been arguing whether it is caused by acquired factors or by genetics. Clinical and animal experiments have shown that structural damage of the cerebral cortex, thalamus and midbrain can cause spine-wave discharge and loss-like behavior. Less than 10% of patients have abnormal CT scans, and 5% to 25% of patients have mild, but not progressive, focal neurological abnormalities, but after all, most patients cannot be explained by acquired injury, given this type The onset of onset and termination of age, the response to drugs and the lack of evidence of central nervous system diseases, combined with changes in EEG, some people believe that the disease is autosomal dominant, with incomplete penetrance, due to this type of attack More brainless organic localized lesions and evidence, EEG shows bilateral symmetrical synchronous 3 times / s spine complex wave, discharge often originated from the deep central structure of the brain (thalamic), affecting both sides of the cerebral hemisphere, Penfield proposed the theory of central brain type epilepsy.

Most patients start from 5 to 10 years old, a few patients start from 1 to 4 years old or 10 years old, and there are reports of adult onset, but it is difficult to determine that these people have no seizures before, more women than men, despite the loss of It is the main feature of the attack, but only about 9% of patients show a simple absence of seizures, and more than 90% of patients with other manifestations.

EEG changes: The episodes of seizures have the highest chance of occurrence in various seizures, and the bilateral symmetrical synchronous 3 times/s spine wave is a typical EEG change of the seizure.

5. Status epilepticus: status epilepticus refers to frequent epileptic seizures such that the patient has not fully recovered from the previous episode and has another episode; continuous tonic-clonic seizure lasts for more than 30 minutes, even if the patient has only one episode, it is called For epilepsy, it can be divided into three types: tonic-clonic, simple partial, complex partial, and epileptic seizure. Among them, tonic-clonic seizure is the most common, and its harmfulness is also the largest. It is reported that the incidence of epileptic seizures in epilepsy patients is 1% to 5%. Before the antiepileptic drugs are widely used, the mortality rate is 10% to 50%, and the mortality rate is still as high as 13% to 20%. Therefore, due attention should be paid to its diagnosis and treatment.

There are many reasons for the status of epileptic seizures. The most common ones are sudden withdrawal of anti-epileptic drugs, fever, etc. In addition, sudden abstinence, deprivation of sleep, acute central nervous system injury (encephalitis, meningitis, cerebrovascular accident, trauma), drugs Poisoning can be induced.

6. Classification of seizures and epilepsy syndrome: The classification of seizures and epilepsy syndrome has undergone a long-term evolution process, such as the classification of seizures in the 1950s and 1970s, which are mainly classified into idiopathic epilepsy and secondary epilepsy according to the etiology. According to the type of clinical seizure, it is divided into grand mal, petit mal and focal seizure. The discharge site according to EEG is divided into frontal lobe, temporal lobe, parietal lobe or occipital lobe epilepsy. According to the clinical features of the episodes, it is described as photosensitive epilepsy, limb pain epilepsy, diencephalic epilepsy and psychomotor epilepsy, which makes the classification of epilepsy more confusing, which brings inconvenience to the treatment. With the deepening of epilepsy, seizures and The classification of epilepsy syndrome is becoming more and more reasonable.

Significant progress has been made in the basic and clinical studies of epilepsy in the past 20 years. The classification of epilepsy in the 1980s has been limited. In 1997, the International Anti-Epilepsy Alliance (ILAE) established the Task Force chaired by Jerome Engel Jr. There are four groups to review and revise the classification of seizures and epilepsy syndrome, and to propose some recommendations for the classification of seizures and epilepsy syndrome (2001), which is intended for the revision of seizures and seizure syndrome classifications or During the transition period, the seizure classification scheme for the 1981 ILAE is still used.

(1) International Anti-Epilepsy Alliance (ILAE, 1981) Classification of seizures:

1 part (local) sexual seizures: seizures start from local.

A. Simpleness: Unconscious disorder, can be divided into exercise, feeling (sense or special feeling), autonomic nerve, psychotic seizures.

B. Complexity: Consciousness disorder, which may be the initial symptom, or may be derived from a simple partial seizure, and may be accompanied by an automatic disorder.

C. Partial seizures secondary generalization: development from partial seizures to generalized seizures.

2 comprehensive (generalized) seizures: bilateral symmetry, conscious disturbances, including tonic-clonic, tonic, clonic, myoclonic seizures (convulsive); absence (typical absence and atypical disappointment), denervation (non-convulsive).

3 seizures that cannot be classified.

4 status epilepticus.

(2) Classification of epilepsy syndrome: Epilepsy syndrome is a specific epileptic phenomenon in which a group of symptoms and signs are concentrated at the same time. The classification of epilepsy syndrome of the International Anti-Epilepsy Alliance (1989) can be summarized as follows:

1 partial epilepsy syndrome: idiopathic (age-dependent onset); symptomatic.

2 systemic epilepsy syndrome: idiopathic (age-dependent onset) including absence, BFNC, JME and GTCS; idiopathic, and / or symptomatic; symptomatic.

3 failed to identify partial and systemic epilepsy and epilepsy syndrome: both systemic and local seizures; no clear systemic and local manifestations.

4 special syndrome.

7. ILAE recommendations for seizure and seizure syndrome classification schemes (2001):

(1) emphasizes that this is not only a classification but also a diagnostic program.

1 Emphasizes the unification of phenomena and causes, anatomical structure and underlying mechanisms, and dilutes the dichotomy principle of previous idiopathic, symptomatic, and systemic, partial classification.

2 Adopt a more flexible and open mindset that reflects the current level of international understanding.

3 The steps of seizure and epilepsy syndrome diagnosis are taken as the core, and each step is described in detail.

The concept of 4 parts has changed a lot and new nouns have been proposed.

(2) The concept of re-explanation:

1 Epileptic attack type: A new definition can represent a single pathophysiological mechanism and anatomical structure caused by seizures, similar to epilepsy syndrome, representing a diagnostic entity that has implications for etiology, treatment, and prognosis, rather than Simply describe the phenomenon.

2 epilepsy syndrome (epilepsy syndrome): is a group of symptoms, signs of specific epilepsy, not only the type of seizures, such as the temporal lobe episode itself does not constitute epilepsy syndrome.

3 reflex epilepsy syndrome: is an epileptic syndrome that can be induced by specific stimuli, including thinking, reading, music and hot water and light stimulation.

(3) The concept of no longer used:

1 advocates that simple partial epileptic attack and complex partial epileptic attack are no longer used, and the type of seizure is no longer distinguished by changes in consciousness. The seizure of conscious disorder should be described individually, in the 20th century. The chronological classification has equated complex partial seizures with temporal lobe epilepsy. It is erroneously considered that the disturbance of consciousness must involve the limbic system. Neocortical epilepsy can also be associated with disturbance of consciousness in the past 20 years. Therefore, the classification of simple and complex partial seizures has no significance.

2 Convulsion and convulsive: a seizure that is mainly a seizure.

3 cryptogenic epilepsy: replaced with probably symptomatic epilepsy.

4 partial seizure (PS) is replaced by focal seizure, Engel et al believe that focal is more able to reflect the nature of such seizures, some are easily misunderstood as epilepsy is only part of the episode or Part of a syndrome, not a part of the brain that originated on one side.

(4) The newly introduced concept:

1 Epileptic disease (epileptic disease): is a clear pathological state caused by a single specific cause, not only the type of seizure, such as progressive myoclonic epilepsy is a syndrome, and Lafora disease (Lafora disease) requires pathological biopsy Confirmed detection of Lafora body (Lafora body), is a genetic disease, can be called epilepsy.

2 epileptic encephalopathy (epileptic encephalopathy): epileptiform discharge itself leads to progressive brain dysfunction, such as acquired epilepsy aphasia (ESES), EEG shows epilepticus status, neuroimaging is normal.

(5) It is recommended to take the idea of a diagnostic axis in the diagnosis of seizures and epilepsy syndrome, first describe the seizure phenomenon, and then determine the type of seizure and epileptic syndrome, and further investigate the etiology and etiology. Central nervous system damage, and finally treatment for the cause and injury.

Examination of seizures and epilepsy syndrome

1. Blood, urine, routine examination of stool and blood sugar, electrolyte (calcium, phosphorus) determination.

2. Cerebrospinal fluid examination: central nervous system infections such as viral encephalitis, increased pressure, increased white blood cells, increased protein, decreased bacterial and bacterial sugars and chlorides, cerebral parasitic diseases may have eosinophilia, central nervous system When the system is syphilis, the syphilis antibody is positive, and the intracranial tumor can have increased intracranial pressure and increased protein.

3. Amino acid analysis of serum or cerebrospinal fluid: possible amino acid metabolism abnormalities can be found.

4. Neurophysiological examination: traditional EEG recording, including scalp electrodes and special electrodes, such as sphenoidal electrodes, snuff electrodes, foramen oval electrodes and intracranial electrodes, intracranial electrodes including subdural electrodes and deep brain Electrodes, subdural electrodes including wire electrodes and gate electrodes, placed in the brain that may be epileptic areas, can often determine epileptic foci and epilepsy areas, and can use electrical stimulation to determine the boundaries of motion, sensation and language, called function The positioning map is very helpful for planning the scope of surgical resection.

Although the traditional EEG recording method can determine the epileptic foci and epilepsy area, it is often impossible to link the electroencephalogram seizures with the clinical symptoms. Therefore, using CCTV or TV images and EEG recording simultaneously For long-term surveillance, it is often possible to record multiple habitual seizures, distinguish between false epilepsy and determine the relationship between the onset of seizures and clinical symptoms.

The newly developed magnetoencephalogram (MEG) provides a more accurate positioning of the deep brain epilepsy discharge source (dipole source).

6. Neuroimaging: CT and MRI greatly improved the diagnosis of abnormal structure of epileptic foci, and 50% to 70% of symptomatic epilepsy (symptomatic epilepsy) can see pathological changes on CT or MRI.

CT and MRI see static structural abnormalities, which cannot be correctly estimated for brain dysfunction caused by epilepsy. Currently, brain function tests have been applied in clinical practice, including positron emission tomography (PET), single photon. Single photon emission tomography (SPECT) and magnetic resonance spectroscopy (MRS), PET can measure the metabolism of sugar and oxygen in the brain, cerebral blood flow and neurotransmitter function changes, SPECT can also measure brain Changes in blood flow, metabolism and neurotransmitter function, but no quantitative PET in terms of quantification, MRS can measure changes in certain chemicals such as acetyl aspartate, choline-containing substances, creatine and lactic acid in the epilepsy area.

7. Neurobiochemical examination: The ion-specific electrodes and microdialysis probes that have been applied can be placed in the epileptic area of the brain to measure some biochemical changes during seizures, during and after the episode.

8. Neuropathological examination: It is a pathological examination of surgically resected epilepsy lesions, which can be determined that the cause of epilepsy is caused by brain tumors, scars, vascular malformations, sclerosis, inflammation, dysplasia or other abnormalities.

9. Neuropsychology: This test can assess cognitive impairment and determine which side of the brain the epilepsy or region is on.

Diagnosis of seizures and epilepsy syndrome

diagnosis

The diagnosis of epilepsy is mainly based on the history of seizures. Witnesses provide a reliable and detailed description of the seizure process, supplemented by EEG evidence of epileptic discharge to confirm the diagnosis.

Differential diagnosis

1. Seizure (seizure) needs to be differentiated from various seizure diseases

1 snoring; 2 syncope; 3 hyperventilation syndrome; 4 migraine; 5 transient ischemic attack; 6 narcolepsy. In addition, epilepsy should be differentiated from paroxysmal psychosis and paroxysmal other visceral symptoms.

2. Symptomatic (epilomatic) epilepsy and the etiology of epilepsy syndrome

(1) Systemic diseases causing epilepsy 1 hypoglycemia; 2 hypocalcemia; 3 amino aciduria; 4 acute intermittent hematoporphyria, abdominal pain, vomiting, diarrhea and peripheral neuropathy associated with epilepsy, Do a urine or blood test.

(2) The history of brain diseases causing epilepsy (history of birth injury, history of febrile seizures, history of encephalitis meningitis, history of traumatic brain injury, history of stroke, etc.) and age of onset may provide some evidence. Physical examination such as the location of the intracranial tumor signs and optic disc edema, cerebral arteriovenous malformation of the head murmur, subcutaneous nodules of cysticercosis (cysticercosis), can provide a clue.

In addition to the obvious diffuse encephalopathy, patients with unexplained etiology often need further examination, such as cerebral angiography radionuclide brain scan, CT, MRI and so on.

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