Many of the causes of epilepsy, but also very complex, only about 1/3 of newly diagnosed cases have a clear cause. In children, congenital n
Many of the causes of epilepsy, but also very complex, only about 1/3 of newly diagnosed cases have a clear cause. In children, congenital neurological defects, such as cerebral palsy may be the main cause of epilepsy, and cerebrovascular disease is the most common cause of adult, accounting for about 12% of new cases. Different age groups and different geographical environment, and even race, there are different causes, but some patients have been unable to find the cause. It is usually referred to as epilepsy or secondary epilepsy with definite cause, and epilepsy, which is not found in the brain, is a primary epilepsy or cryptogenic epilepsy.
Idiopathic epilepsy is also called idiopathic epilepsy, refers to the addition of genetic factors do not have other potential causes, through a variety of inspection detailed history and physical examination as well as the current can also failed to prove that there is a kind of epilepsy caused by brain organic disease of epilepsy or systemic signs of metabolic diseases the accounts for about 2/3 of epilepsy. It has the age dependence of the onset, the clinical manifestation of systemic seizures, EEG more for the whole brain, the performance of bilateral symmetrical synchronous spike slow wave complex, and significant family genetic predisposition and other characteristics. This kind of patient during seizures showed generalized tonic clonic seizures, absence seizures or myoclonic seizures. The secondary epilepsy is also known as symptomatic epilepsy or acquired epilepsy, epilepsy is only a symptom of brain disease or systemic disease, accounting for 23% of the total number of patients with epilepsy ~ ~ 39%. With the development of medical science and the advent of advanced medical instruments, the detection rate of brain lesions is greatly improved. Part of the original can not find the cause of the so-called primary epilepsy found the reason. There are some patients with progression of the disease, the etiology may be gradually revealed, such as some early brain tumors, imaging also failed to prompt abnormal clinical manifestations mimicking primary epilepsy, and the progress of the disease, may be abnormal and then review, that is to say the diagnosis of primary epilepsy rate will be relatively high, and the actual is constantly narrowing.
The father of a patient suffering from epilepsy caused by the incidence of epilepsy in the future about 6%, the mother of a person who has epilepsy to be 2 times higher, parents with primary epilepsy, the offspring will have an increased chance of suffering from epilepsy for the ~ ~ ~ 12%. Genetic factors play an important role in primary epilepsy.
Two, prenatal and intrapartum injury
Prenatal and intrapartum injury, brain formation disorder is a common cause of epilepsy in infants and young children. Early embryos of rubella, cytomegalovirus infection, uterine bleeding, radiation, mother serious body disease, certain medicines and chemical reagents can affect fetal brain development, there is a common agyria pachygyria, and small polygyria, small brain disease, ectopic neurons, porencephaly; brain abnormalities in the corpus callosum dysplasia, transparent septal defect or cyst development of midline structures. Perinatal asphyxia, brain hemorrhage, narrow pelvis, high forceps, delivery speed, the fetus is too large can cause brain damage to the fetus, also may be the pathological basis of epilepsy. In addition, after the age of 10 even after 20 to 30 years old clinically complex partial seizures, has been confirmed by operation and pathology department of multi childbirth fetal head after the birth canal, canal by compression and pressing down the brain, produce tentorial hernia caused by vascular compression, resulting in the basal surface of the temporal lobe acute ischemia finally, due to temporal sclerosis and epilepsy.
Three, developmental defects
5.5% cases of primary epilepsy and 18% cases of epilepsy are associated with developmental defects, which are the most important secondary factors in children. Of the 1000 surviving infants, there were between 3 and 6 cases of cerebral palsy and / or moderate to severe mental retardation, of which 1/3 had seizures.
Four, febrile convulsion
After 3 months to 6 years, about 3% to 4% children with febrile seizures can occur, which occurred in 90% at the age of 3, 15 months is the first peak of febrile convulsion. Recurrent seizures accounted for 30% to 40%, and the 3 or more episodes accounted for 10%. Epilepsy after febrile seizures may be 2% to 3%. However, the following risk factors: 1 attack time more than 15 minutes. 2 localized seizures. 3 before the onset of abnormal nervous state. Repeated within 4.24 hours. 5 siblings or parents with a history of epilepsy. 5 of these 2 or more of the development of epilepsy will rise to the opportunity of 6% ~ 15%. Another study showed that the incidence of febrile seizures each time will increase the risk of recurrence by 1 times, while the age, sex, the first type, the initial temperature, family history and recurrence rate.
Five, cerebrovascular disease
Cerebrovascular disease is the main cause of epilepsy in the elderly. The incidence of epilepsy after stroke was 7.2 ~ 8.9%. Recent studies have shown that in the acute period within 1 years after the incidence of epilepsy was 3% to 10 years, up to 8.9%; the incidence of different epilepsy of different cerebrovascular disease, 4.5% ~ 17.6% and 6.2% ~ 19.2% cerebral hemorrhage, subarachnoid hemorrhage, cerebral thrombosis, cerebral embolism in 3.9% ~ 15.6%, 9.3% ~ 18.2%, transient ischemic attack as 4.5% ~ 5.5%. Cerebrovascular disease, whether hemorrhagic or ischemic, after the acute phase can still have seizures, about 33% of ischemic cerebrovascular disease in the future of epilepsy. The incidence of epilepsy is not parallel with the size of the lesion and the severity of the disease, but it is closely related to cortical damage.
Cerebral arteriovenous malformations often appear in adulthood in central zone and near the seizures, temporal lobe lesions. According to statistics, the first half of patients with symptoms of epilepsy. Can be expressed as partial seizures, absence seizures and generalized tonic clonic seizures. These patients may have a history of unilateral headache and / or subarachnoid hemorrhage. It may also occur in epilepsy or intracranial venous sinus thrombosis in postpartum superior sagittal sinus thrombosis more common showed generalized tonic clonic seizures, often accompanied by increased intracranial pressure, nervous system and other limitations of signs. Cerebrovascular disease incidence of epilepsy is not very high, but the incidence of cerebrovascular disease itself is very high, especially in the elderly population is higher, so cerebrovascular disease is still one of the most common causes of epilepsy. Cerebral infarction or cerebral hemorrhage is more prone to seizures in children than in adults, 16% and 25%, respectively.
Six, craniocerebral trauma
Traumatic brain injury is one of the common causes of seizures. Can be caused by bullets, traffic accidents and accidental damage and even fighting, has a relationship with the degree of trauma, injury site and injury time. The more severe craniocerebral injury, the higher the incidence of epilepsy. General according to the length of time is divided into 3 cases: 1 immediate attack, within a few hours after the onset of epilepsy, accounting for about 3%. May be associated with brain hemorrhage, depression and other stimuli as well as brain cell injury, a large number of acetylcholine release and other related, no recurrence after a seizure. 2 seizures occurred within a few hours to 1 months after injury, accounting for about 13%, which may be related to wound healing or secondary brain tissue response. 3 late onset, after the injury to the seizure of 1 months to several years, accounting for about 84%, and more with brain contusion and laceration, brain hematoma, meningeal scar, brain cyst, brain atrophy and other related.
Seven, intracranial infection
Intracranial infections include bacterial, viral, fungal, and parasitic infections, which can lead to seizures.
Eight, brain tumor
Brain tumors are one of the most common causes of symptomatic epilepsy. About of patients with intracranial tumors have seizures, while in the cerebral hemisphere, there is a seizure of about 50%. Slow growing tumors, such as meningiomas or low-grade gliomas, are more prone to seizures than those with faster growth, such as glioblastoma. Sometimes epilepsy is not only the first symptom of brain tumor, but also the only symptom.
Nine, metabolic disorders
Hyperglycemia, hypoglycemia, hypocalcemia and uremia can cause seizures. The blood glucose is lower than 2.8 ~ 3.36 mmol/L (~ 50 ~ 60 mg/dl). The common causes of hypoglycemia are islet cell tumor, insulin therapy, pituitary insufficiency, adrenal insufficiency and hypothyroidism. Sudden increase in blood glucose and hypertonic state can cause epilepsy.
5% ~ 15% of alcohol poisoning patients with seizures, acute and chronic alcoholism can have seizures, 2/3 and stop drinking related. More than 20% of newly diagnosed adults with epilepsy were the most dangerous factors. Stop the attack is usually chronic alcoholic drink, but excessive drinking may also occur in only a few weeks after the abrupt discontinuation or high alcohol intake reduction is more likely to happen suddenly. Usually stop wine to attack time of 18 ~ 24 hours, the onset of the attack occurred in the stop drinking for 7 ~ 48 hours. Usually within 6 hours there are often 2 to 4 episodes. 60% for several episodes, 3% for status epilepticus, 30% developed delirium tremor. In addition, ethanol in some epileptic patients may be a special predisposing factors, and epilepsy patients after application of ethanol due to poor compliance, reduce the absorption of induced liver enzymes, will lead to a decline in the level of antiepileptic drugs may also be one of the factors to induce epilepsy. Carbon monoxide poisoning can cause seizures, but rare. Inhalation of high concentrations of oxygen or attack in a high-pressure oxygen chamber has the possibility of epilepsy.
The incidence of epilepsy after craniocerebral surgery and pathological nature, location, preoperative condition, surgical approach has a certain relationship, the higher incidence of epilepsy after surgery in patients with brain abscess, meningioma, glioma, supratentorial aneurysms. Alzheimer's disease 15% to 1/3 seizures, Peake's disease can also have seizures but few. Neurocutaneous syndrome, such as facial hemangioma (Sturge - Weber syndrome), tuberous sclerosis, nerve fiber disease can have seizures. Seizures occurred in about 5% ~ 10% of multiple sclerosis. Systemic lupus erythematosus with neurological complications of 44% patients with epilepsy, generalized tonic clonic seizures may occur in the early stage, the individual is the starting performance. Some drugs can induce seizures, such as penicillin (especially intravenous or intrathecal injection), long-term use of isoniazid to consume large amounts of vitamin B6, without supplementation induced epilepsy; antidepressant imipramine, amitriptyline, can cause seizures; drugs such as e four n, Nicole brake m, strychnine, camphor, picrotoxin and other stimulants excess; such as insulin, prednisone and other anticholinergic drugs, aminophylline, chloroquine, baclofen can also cause epilepsy.