Intractable epilepsy

Introduction to refractory epilepsy Intractable epilepsy (retractableepilepsy) is also called refractableepilepsy, and there is no uniform definition at home and abroad. Usually refers to no central nervous system progressive disease or space-occupying disease, but clinically prolonged, after more than 2 years of regular anti-epileptic treatment, try the main anti-epileptic drugs alone or in combination, to achieve the patient can tolerate the maximum dose, the blood drug concentration is effective Scope, still can not control the onset, and affect daily life, can be identified as refractory epilepsy. Refractory epilepsy accounts for about 20% to 30% of patients with epilepsy. basic knowledge The proportion of illness: 0.005% Susceptible people: no special people Mode of infection: non-infectious Complications: Traumatic asphyxia

Refractory epilepsy

(1) Causes of the disease

1. The causes of refractory epilepsy are numerous, most of which have brain lesions, such as hippocampal sclerosis, brain trauma, tumor, tuberous sclerosis and congenital dysplasia.

2. Influential factors of refractory epilepsy include:

Incidence within 11 years of age;

2 The age of onset is late or the medication may not be controlled for a long time;

3 complex partial seizures, infantile spasms, Lennox-Gastaut syndrome, etc. are easily developed into refractory epilepsy;

4 frequent episodes, each time the symptoms of the attack and the duration of the elderly;

The background of 5EEG is slow wave, frequent epileptic discharge, and the blood concentration of AEDs has reached the therapeutic level and there is still epileptiform discharge;

6 with intelligent and mentally handicapped;

7 long-term sustained psychological tension;

8 brain organic diseases.

(two) pathogenesis

In 1985, an epidemiological survey of rural epilepsy in 22 provinces and cities in China found that 40.4% of seizures were naturally relieved for more than 2 years, and natural remission was more than 5 years, accounting for 27.1%, while patients with epilepsy experienced reasonable and regular drug treatment. The complete control rate is only 50% to 85%.

Reasons for treatment failure:

1 The type of seizure is incorrectly judged and the medication is improper;

2 The frequency of seizures is estimated incorrectly and the dose is not sufficient;

3 irregular medication, can not maintain steady state effective blood concentration;

4 epilepsy itself is refractory epilepsy.

Various types of epilepsy can lead to refractory epilepsy. Studies have found that patients with refractory epilepsy have multiple drug resistance gene (MDRI) overexpression, Tishler (1995) reported 319 patients with refractory epilepsy surgery The expression of MDRI mRNA in the epileptic foci was resected, 11 of which were 10 times higher than normal brain tissue, and there were increased transmembrane P-glycoproteins in capillaries and glial cells. The concentration of anti-epileptic drugs (AEDs) in the brain was only 25% of patients with negative MDRI mRNA gene expression may be associated with refractory epilepsy.

Refractory epilepsy prevention

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 to patients. Physical, psychological and social adverse effects.

Early prevention and early diagnosis of symptomatic epilepsy syndrome, early treatment is also very important. For those with genetic factors, the importance of genetic counseling should be emphasized. The family survey should be conducted in detail to understand the 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.

Refractory epilepsy complications Complications, 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.

Refractory epilepsy symptoms Common symptoms Anxiety, auditory hallucinations, palpitations, palpitations, abdominal pain, palpitations, frontal lobe epilepsy, forehead area, myoclonus, frontal lobe epilepsy...

Refractory epilepsy can be found in various types of epilepsy, children with Lennox-Gastaut syndrome and infantile spasms, and adults with common complex partial hair as a representative.

1. Lennox-Gastaut syndrome

Also known as the variation of absence seizures, accounting for 5% to 10% of pediatric epilepsy, about 36% have clear causes such as birth injury, brain trauma and encephalitis, etc. The main clinical features:

1 seizures of various forms, common atypical absence of seizures (17% to 60%), loss of tension and seizures (26% to 56%), myoclonic seizures (11% to 28%) and tonic seizures (17% ~ 92%);

2 often accompanied by mental retardation;

3EEG can be seen on both sides of the synchronous spine slow wave release from 1 to 2.5 Hz;

4AEDs have poor efficacy and control rate is only 0-20%.

2. Infantile snoring

Also known as West syndrome, often in infants and young children, can be caused by multiple causes of fetal, perinatal and postnatal, such as cerebral ischemia and hypoxia, birth trauma, trauma, central nervous system infection, metabolic disorders and Nodular sclerosis, etc., showing transient multiple strong myotonic or clonic seizures, common sputum, nodding, Mom reflex (hug reflex) sputum episodes, each episode lasts 1 to 15 s, often consecutive episodes several times to Dozens of times, after waking up and before going to sleep, intensive, with sweating, flushing and shouting, half of children with GTCS, absence of seizures, etc., most with mental retardation, EEG is highly arrhythmia (hypersarrhythmia), for AEDs The reaction is poor and the control rate is only 40% to 50%.

3. Complex partial seizures

About 70% are caused by temporal lobe lesions, and about 30% are caused by frontal, apical and occipital lesions. The main manifestations are mental behavioral abnormalities. The former is called psychomotor seizure. The episodes with conspicuous disturbances are prominent features. Comprehensive sexual seizures, common types:

1 special sensory episodes: such as illusory scent (hookback episode), illusion (visual enlargement, smaller, farther, closer and distorted), auditory hallucinations and illusions;

2 visceral sensory seizures: such as chest and abdomen hot gas surge, palpitations, abdominal pain, urgency, etc.;

3 memory disorder episodes: such as strangeness, familiarity (like deja vu, old revisiting, etc.);

4 affection disorders: such as fear, anxiety, euphoria, anger, etc.;

5 thought disorder episodes: such as forced thinking, delusion, etc.;

6 automatic disease: simple automatic symptoms of behavioral autonomic symptoms, oropharyngeal autopsy, complex automatic symptoms of night snoring and roaming.

Refractory epilepsy

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 sugar and chloride in bacterial infections, eosinophilia in brain parasitic diseases, syphilis in central nervous system syphilis The spirochete 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 recordings, 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 identify areas of epileptic foci and epilepsy, and can use electrical stimulation to determine the boundaries of motion, sensation, and language, called functional localization maps, for planned surgical resection The scope is very helpful.

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).

5. Neuroimaging

CT and MRI greatly improve the diagnosis of structural abnormalities of epilepsy, and 50% to 70% of 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.

6. Neurobiochemical examination

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 between seizures, during and after the episode.

7. 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.

8. Neuropsychological examination

This test assesses cognitive impairment and determines which side of the brain the epileptic focus or area is on.

Diagnosis and diagnosis of refractory epilepsy

Diagnostic criteria:

There is no uniform diagnostic criteria for refractory epilepsy at present, and Schmidt proposes a standard for refractory epilepsy in children:

Level 0: Use a non-first-line AEDs, regardless of dose.

Class I: Use first-line AEDs, lower than the recommended dose.

Level II: First-line AEDs, in the recommended dose range.

Grade III: First-line AEDs, plasma concentrations are within the therapeutic range.

Grade IV: first-line AEDs, maximum tolerated dose.

Class V: One or more first-line AEDs, the maximum tolerated dose.

Class VI: One or more first-line AEDs, maximum tolerated dose and several second-line AEDs.

Grades 0 to II are iatrogenic refractory epilepsy, and grades III to VI are true refractory epilepsy. Domestic Huang Yuangui believes that the necessary conditions for the diagnosis of refractory epilepsy are:

1 The diagnosis of epilepsy is correct and the classification is correct;

2 using first-line AEDs single or multi-drug combined with regular treatment;

3 dose reaches the maximum tolerated dose, blood concentration is in the treatment range;

4 After the above treatment for more than 2 years, the seizure cannot be controlled;

5 affect the daily life.

To determine the frequency of seizures after refractory epilepsy, there is still no standard. GTCS is more than 4 times per month. It is more suitable for complex partial seizures, absence seizures and myoclonic seizures. .

Differential diagnosis:

Diagnostic errors, improper drug selection, inadequate doses, poor patient compliance, etc., can lead to iatrogenic refractory epilepsy, such as benign acid in children with benign partial epilepsy, if using AEDs that reduce the level of wakefulness in children Phenobarbital can increase seizures, carbamazepine is ineffective or increases seizures in myoclonic epilepsy, and myosin epilepsy is preferred for diazepam, nitrodiazepine and clonazepam (clonazepam), but benzodiazepine The class action time is short, the drug is easy to relapse, and the side effect of reducing the wake-up level is large. It is not suitable for children. If the drug is not taken on time, alcoholism, lack of sleep and excessive fatigue can make the clinical attack last for a long time. Patients with poor efficacy are classified as refractory, and pseudoseizures (pseudoseizures) must be excluded. The latter can coexist with epilepsy. At this time, it is necessary to pay attention to identification. Video EEG is important for identification. Prolactin after seizures. The level is elevated and there is no change in pseudo seizures.

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