What Are Neonatal Seizures?

Neonatal seizures refer to epilepsy that occurs within 28 days of birth. There are many causes, such as genetic inheritance, congenital abnormalities, childbirth injuries, intracranial infections, craniocerebral trauma, febrile epilepsy, etc., can cause epilepsy. The clinical manifestations are complex and diverse, and many types of seizures and epilepsy syndromes can be seen. Due to the imperfect development of the neonatal cerebral cortex, any adverse stimulation can cause abnormal discharge of the cerebral cortex, and the positive rate of EEG examination is relatively high.

Basic Information

Visiting department

Pediatrics, Neurology

Common locations

Brain

Common causes

Heredity, congenital abnormalities, birth trauma, intracranial infection, etc.

Common symptoms

Neonatal manifestations of ankylosing eyeballs, repeated blinking and eyelid twitching, non-irritating sucking and chewing mouth-cheek-tongue movements, salivation, apnea, etc.

Causes of neonatal epilepsy

Prenatal factors

There are fetal brain development abnormalities, fetal cerebral vascular occlusion, prenatal fetal infections, mothers taking hormones, narcotics, alcohol and other fetal congenital metabolic defects during pregnancy, as well as mothers' pregnancy and hereditary convulsions.

2. Childbirth factors

There are various types of birth injuries, intracranial or extracranial infections of the fetus, and accidental injection of anesthetics on the scalp of the child when the pregnant woman has difficulty giving birth.

3. Postpartum factors

There are metabolic disorders, postpartum infections, intracranial hemorrhage, and hypoxic-ischemic encephalopathy. Among them, perinatal asphyxia and hypoxia are the most common causes, followed by metabolic abnormalities and birth injuries.

4. Drug factors

Drug overdose or poisoning: such as respiratory stimulants, aminophylline, etc. Drug withdrawal syndrome

5. Other

Congenital malformations and brain hypoplasia can cause epilepsy in the neonatal period; neonatal erythrocytosis and sweltering syndrome can also cause neonatal epilepsy; primary epilepsy and intracranial tumors are rare.

Clinical manifestations of neonatal epilepsy

Tiny

The most common type of seizures in newborns (50% of neonatal epilepsy). It manifests as ankylosing eyeballs, repeated blinking and eyelid twitching, non-irritating sucking and chewing mouth-cheek-tongue movements, drooling, apnea, sometimes swimming and cycling like limbs, or single limb tremor, or fixation In one position, no rigidity or clonic tics of the limbs occur.

2. Tonic

Both term and immature infants are visible. It is manifested as tonic extension of the extremities, sometimes flexion of the upper limbs, extension of the lower limbs, often accompanied by apnea and upturned eyes, which are mostly caused by cerebral organic lesions rather than metabolic disorders, which are serious symptoms.

3. Multifocal clonic

More common in term children. It is characterized by muscle cramps with small amplitudes of multiple limbs, 1 to 3 times per second, and its convulsions can quickly turn from one limb to the other, or from one side of the body to the other, often accompanied by disturbance of consciousness.

4. Focal clonic

Full-term infants are more common than premature infants and present as localized clonics. They usually start from one limb or one face, and then expand to other parts on the same side of the body. Most of them are not accompanied by a disturbance of consciousness and have no positioning significance. More common in metabolic abnormalities, such as hypoglycemia, hypocalcemia, hypomagnesemia, and also in HIE or subarachnoid hemorrhage, the prognosis is generally good.

5. Systemic myoclonus

Neonatal period is rare, single or multiple limbs repeatedly synchronized flexor spasm during the onset, its occurrence often indicates diffuse brain damage, poor prognosis.

Neonatal epilepsy

EEG

In the past, the localization of epilepsy mainly relied on electroencephalography (EEG), including ordinary EEG, sleep EEG, 24-hour dynamic EEG, deep brain electrodes, subdural electrodes and oval holes, and sphenoid ridge electrodes Wait. EEG is not only valuable for the selection of indications for epilepsy surgery, but also can locate the primary focus of epilepsy discharge. The clinical application of 24-hour video EEG monitoring method can clearly diagnose the epilepsy focus through long-term monitoring.

2. Imaging technology

The emergence of CT, MRI and functional imaging methods such as positron emission computed tomography (PET) has enabled many patients with secondary epilepsy caused by lesions such as tiny tumors or cavernous hemangioma to be treated. Functional magnetic Resonance imaging (FMRI) is a new imaging technique that provides brain function localization with high spatial and temporal resolution. Its imaging depends on the detection of an increase in signal intensity at the corresponding site caused by local hemodynamic changes. At present, FMRI research on brain function has been recognized and has been used to locate the visual, auditory, and motor cortex.

Neonatal epilepsy diagnosis

The form of seizures in neonates is often indefinite, the clinical manifestations are diverse, and the diagnosis is difficult. If the tics are repetitive, periodic, or accompanied by abnormal eyeballs, apnea and other abnormalities, it should be considered a seizure, which can be determined by EEG. The diagnosis of neonatal epilepsy should be comprehensively combined with medical history, physical examination, laboratory examination, EEG and imaging examination.

Neonatal epilepsy treatment

Neonatal epilepsy should be diagnosed quickly, and the cause and symptomatic treatment should be given as soon as possible. Many causes such as hypocalcemia, hypoglycemia, and vitamin B6 deficiency, etc. Once the cause is eliminated, anti-epileptics are often not needed, and epilepsy can stop. Drug withdrawal syndrome and familial benign neonatal epilepsy are self-limiting diseases, and epilepsy can stop within days to weeks.

Neonatal epilepsy prognosis

Neonatal epilepsy has a poor prognosis, with a mortality rate between 10% and 30%, and sequelae in approximately 30% of survivors. Mainly manifested as mental retardation, paralysis, epilepsy, ataxia, hyperactivity, audiovisual impairment, language disorder, and mild brain dysfunction can also be seen. The prognosis of neonatal epilepsy mainly depends on the primary disease and the degree of brain damage. Clinical and EEG can also provide valuable information. Factors related to prognosis:

Cause

Severe hypoxic-ischemic encephalopathy has a high mortality rate and a high incidence of sequelae; bilirubin encephalopathy, intracranial hemorrhage, purulent meningitis, and toxic encephalopathy; metabolic imbalance and high-temperature prognosis are good.

2. Duration of epilepsy and consciousness during epilepsy

Patients with obvious psychiatric disturbances, reflexes, or other abnormal neurological signs have a poor prognosis during intermittent periods; despite reasonable treatment, seizures persist and the prognosis is longer than 3 days.

3. EEG

The background wave showed burst suppression or flat section, frequent epilepsy waves, or abnormal EEG time longer than 1 week.

4. Drugs

Patients with epilepsy with a phenobarbital loading of 30 mg / kg who have more than one epilepsy or who need to add other anti-epileptic drugs have a poor prognosis.

5. Diagnosis and treatment

Patients diagnosed early and treated early have a good prognosis, but those who do not respond promptly or correctly affect the prognosis.