OVERVIEW
Epilepsy is a chronic disease characterized by sudden abnormal discharges of neurons in the brain, resulting in transient brain dysfunction. According to the latest epidemiological data in China, there are about 9 million epilepsy patients in China, of which 5-6 million are active epilepsy patients, while about 400,000 new epilepsy patients are added every year, of which about 3 million are patients with drug-refractory epilepsy.
Questions you may be concerned about
What is Epilepsy
Epilepsy is a chronic brain disorder caused by abnormal neuronal discharges in the brain.
Epilepsy, also known as crohns and epilepsy, is a chronic brain disease caused by a variety of reasons that make the neurons in the brain brain are highly assimilated and abnormal discharges occur. Typical clinical manifestations of epileptic seizures are sudden fainting, foaming at the mouth, and convulsions of the limbs, which last for a short period of time and are similar each time.
Epilepsy is mainly treated with medication and surgery. Most patients can effectively control their symptoms by taking medication, while some patients can be treated with surgery, which maximizes the possibility of removing the lesion and protects the surrounding nerve cells to maintain normal function.
Types of Seizures
1. Seizure classification
Currently, the seizure classification scheme proposed by the International League Against Epilepsy (ILAE) in 1981 is commonly used. Seizures are categorized into partial/focal seizures, generalized seizures, and seizures that cannot be classified.In 2010, the International League Against Epilepsy proposed an updated seizure classification scheme, and the new scheme reclassifies and supplements seizures.
(1) Partial/focal seizures are seizures with onset symptoms and EEG changes suggesting that “neurons in a part of the cerebral hemisphere are activated first”. They include simple partial seizures, complex partial seizures, and secondary generalized seizures.
(2) Generalized seizures are seizures in which the onset of symptoms and EEG changes suggest that “both hemispheres of the brain are affected at the same time”. They include apoplectic, myoclonic, tonic, clonic, tonic-clonic, and atonic seizures.
(3) Seizures that cannot be categorized Seizures that cannot be categorized due to insufficient or incomplete information, or that cannot be categorized in the current classification criteria (e.g., spasmodic seizures).
(4) Newly recognized seizure types in recent years Includes myoclonic agnosia, negative myoclonus, myoclonus of the eyelids, and demented laughter seizures.
2. Classification of epilepsy syndromes
According to the different causes of epilepsy, they can be categorized into idiopathic epilepsy syndromes, symptomatic epilepsy syndromes, and possible symptomatic epilepsy syndromes.
(1) Idiopathic epilepsy syndrome A syndrome in which there is no structural damage to the brain or other neurological signs and symptoms other than epilepsy. It most often begins before puberty and has a favorable prognosis.
(2) Symptomatic epilepsy syndrome A lesion or abnormality of the central nervous system caused by various reasons, including structural abnormalities of the brain or various factors affecting brain function. With the advancement of medicine and the continuous development and abundance of examination methods, more and more epilepsy cases are able to find the cause.
(3) Possible symptomatic epilepsy syndrome or cryptogenic epilepsy Considered to be symptomatic epilepsy syndrome, but the cause is currently unknown.
(4) Reflex epilepsy syndromes Refers to epilepsy in which almost all seizures are triggered by specific sensory or complex cognitive activities, such as reading epilepsy, startle epilepsy, visual reflex epilepsy, hot bath epilepsy, and cardboard epilepsy. The seizures also disappear when the triggers are removed.
(5) Benign epileptic syndrome An epileptic syndrome that is easy to treat or can be completely relieved without treatment, leaving no sequelae.
(6) Epileptic encephalopathy Refers to progressive brain dysfunction caused by the epileptic abnormality itself. Its cause is mainly or entirely due to epileptic seizures or frequent epileptic discharges between seizures. Mostly neonatal, infantile, and childhood onset. EEG is markedly abnormal and medication is ineffective.
Etiology
Epilepsy can be caused by many reasons, especially lesions of the cerebral cortex, and is generally believed to be related to the following four factors:
1. Heredity
Epilepsy tends to occur in some families of patients with a history of epilepsy or with congenital central nervous system or heart malformations.
2. Brain damage and brain injury
Epilepsy can be caused by viral infection, radiation exposure or other causes of embryonic dysplasia during embryonic development; birth injury during labor; and craniocerebral trauma.
3. Other craniocerebral diseases
Brain tumor, cerebrovascular disease, intracranial infection can cause epilepsy.
4. Environmental factors
There are more male patients than female patients, and the incidence rate is higher in rural areas than in urban areas. In addition, fever and mental stimulation are also triggers of epilepsy.
Symptoms
1. Generalized tonic-clonic seizure
Characterized by sudden loss of consciousness and generalized tonicity and convulsions, a typical seizure can be divided into tonic, clonic and postictal phases.
2. Loss of consciousness seizure
Typical apoplectic seizures are characterized by sudden onset, suspension of movement, staring, and inability to respond to calls, usually lasting 5-20 seconds, rarely lasting more than 1 minute. It is mainly seen in children with catatonic epilepsy.
3. Tonic seizures
Tonic seizures are characterized by strong and persistent contraction of the whole body or bilateral muscles, and muscle rigidity, which fixes the limbs and body in a certain tense position.
4. Myoclonic seizures
It is a sudden, rapid and short contraction of the muscles, which is similar to the electric shock-like shaking of the body or limbs, sometimes for several times in a row, mostly after waking up. It can be a generalized movement or a localized movement.
5. Spasticity
Infantile spasms, manifested as sudden, short-lived tonic flexion or extension contractions of the trunk muscles and bilateral limbs, mostly manifested as episodic nodding, and occasionally episodic tilting back. The whole process of muscle contraction is about 1 to 3 seconds, often in clusters.
6. Dystonic seizures
It is due to the sudden loss of bilateral partial or generalized muscle tone, resulting in the inability to maintain the original posture, sudden collapse, limb drop and other manifestations, the seizure time is relatively short, lasting a few seconds to more than 10 seconds, seizures of short duration are not accompanied by obvious impaired consciousness.
7. Simple partial seizure
The duration of the seizure lasts from a few seconds to more than 20 seconds, and seldom exceeds 1 minute.
8. Complex partial seizures
The seizure is accompanied by different degrees of consciousness disorder. It is characterized by a sudden stop of movement, straightening of the eyes, no response to the call, no fall, and no change in color. Some patients may have automatisms, which are involuntary and unconscious movements.
9. Secondary generalized seizures
Simple or complex partial seizures can be followed by generalized seizures, most commonly followed by generalized tonic clonic seizures.
Examination
1. EEG (electroencephalogram), BEAM (electroencephalogram topography), Holter (dynamic electroencephalogram monitoring) can show clear pathologic waves, spiking waves, sharp waves, spiking-slow waves or sharp-slow waves.
2. Cranial CT, Cranial MRI, MRA (Magnetic Resonance Angiography), DSA (Digital Subtraction Angiography) If secondary epilepsy is present, further cranial CT, cranial MRI, MRA, DSA should be performed to find out the corresponding lesions.
3. Lumbar puncture: CSF examination, may have changes.
Diagnosis
Accurate diagnosis of epilepsy plays a great role in the treatment of epilepsy. Common diagnostic methods mainly include routine blood, urine and stool examination and blood glucose and electrolyte (calcium and phosphorus) measurement; cerebrospinal fluid examination; neuroimaging examination; neuropathological examination; neuropsychological examination; neurophysiological examination and so on.
Differential diagnosis
By doing cerebral angiography, nuclear brain scan, CT, MRI and other tests help to differentiate. Epileptic seizures need to be differentiated from various seizure disorders, such as hysteria; syncope; transient ischemic attack and other symptoms.
Treatment
1. Medication
(1) The diagnosis of epilepsy is clear.
(2)Antiepileptic drugs for the first clinical seizure If there is no epileptiform abnormality in the EEG of the first seizure or there is no possible cause in the history of the disease, the drugs can be temporarily withheld, and close observation can be carried out; if there is an epileptiform abnormality in the EEG of the first seizure or if there is a possible cause in the history of the disease, the antiepileptic drugs should be started; the first seizure, if it is proved that it is a symptomatic epilepsy, should be given antiepileptic drugs along with the etiologic treatment.
(3) Selection of antiepileptic drugs Carbamazepine and oxcarbazepine can be used for partial seizures; Sodium valproate, lamotrigine, keplan, phenobarbital can be used for most types of seizures; Ethosuximide or sodium valproate is preferred for cataplexy seizures; Carbamazepine and oxcarbazepine can aggravate cataplexy and myoclonic seizures.
(4) Combination of antiepileptic drugs Single-drug treatment is ineffective when you can consider a reasonable variety of drug therapy, should choose different mechanisms of antiepileptic drugs used in combination, the current recommendation of the commonly used combination of sodium valproate, lamotrigine, Tourette’s; sodium valproate, lamotrigine, Kaplan.
(5) Antiepileptic treatment needs to be continuous medication should not be easily discontinued Currently, it is believed that at least 3 years of seizure-free before considering whether the drug can be gradually discontinued. The discontinuation process takes about 1 year.
2. Surgery
The main indications are: ① clear drug-refractory epilepsy patients, regular antiepileptic drug treatment for more than 2 years, and for epilepsy with structural lesions, such as early diagnosis of medial temporal lobe epilepsy patients, infants and children with catastrophic epilepsy should be appropriate for early surgery; (2) the existence of a confined lesion capable of being resected (except for callosotomy, vagus nerve stimulation); (3) the absence of progressive etiologic factors ( Rasmussen’s encephalitis excluded); (4) the patient’s willingness to undergo surgical treatment.
3. Neuromodulation for refractory epilepsy
Vagus nerve stimulation (VNS) treatment is mainly applicable to patients with refractory epilepsy that cannot be controlled by antiepileptic drugs, and epilepsy patients who are not suitable for craniotomy or are not willing to undergo craniotomy. Through VNS (Vagus Nerve Stimulation) treatment, 6% to 8 of drug-refractory patients are completely seizure-free; 60% of patients have a >50% reduction in seizure frequency; about 30% of patients have a 50% reduction in seizure frequency, and the patients’ moods, cognition, and quality of life are improved to different degrees.
4. Ketogenic diet for treatment of refractory epilepsy
Ketogenic diet, i.e. high-fat, low-carbohydrate and appropriate protein diet, has been used in clinical treatment of drug-refractory epilepsy for 90 years, with 1/3 of the children experiencing a 90% reduction in seizure frequency, and 1/3 experiencing a reduction in seizure frequency of more than 50%.