What Are the Most Common Causes of Brain Swelling?

Cerebral edema refers to the pathological phenomenon that the increase of water in the brain leads to the increase of brain volume, and it is the response of brain tissue to various pathogenic factors. Can cause intracranial hypertension, damage to brain tissue, clinically common in nervous system diseases, such as craniocerebral trauma, intracranial infections (encephalitis, meningitis, etc.), cerebrovascular diseases, intracranial space-occupying diseases (such as tumors), Seizures and systemic diseases such as toxic dysentery and severe pneumonia.

Western Medicine Name: Brain edema
English name: cerebral edema
Disease site: brain tissue

Main cause: Craniocerebral injury, intracranial space-occupying lesions, intracranial inflammation, cerebrovascular disease, cerebral hypoxia, etc.
Contagious: Non-contagious
Hereditary: Non-hereditary

Causes of cerebral edema

1. Craniocerebral injury. Various types of craniocerebral injury can directly or indirectly cause cerebral contusion and laceration, which can cause cerebral edema and intracranial hematoma. Compression of local brain tissue can also cause cerebral edema. Skull depression fracture, which causes compression to the brain tissue, or directly penetrates the brain tissue due to the fracture of the fractured piece, brain edema appears in the affected area, the shock wave of the shock injury hits the chest, or the chest is directly squeezed, which makes the pressure of the superior vena cava sharp Increased pressure spreads to the brain and impacts the brain tissue, causing widespread diffuse point bleeding of capillaries in the brain tissue, increasing capillary permeability, and often with diffuse brain edema and diffuse axonal injury to the brain, which can continue Severe diffuse brain edema.

2.Intracranial space-occupying tumors cause compression of surrounding brain tissue or block cerebral venous return, increased venous pressure, intracranial congestion, cerebrospinal fluid circulation machine malabsorption, and tumor biological toxicity, etc. Impact, damage or destruction of the blood-brain barrier, permeability of blood vessel walls

Brain edema Sexual increase, resulting in localized cerebral edema. Brain edema associated with primary malignant tumors of the brain is particularly significant. Brain metastases from lung cancer, choriocarcinoma, etc., whether single or multiple, have severe brain edema around the lesion.

3. Intracranial inflammation, encephalitis, meningitis, ventriculitis, cerebral abscess and sepsis, diffuse inflammation in the skull, often secondary to different degrees of cerebral edema, which is related to the toxicity of the pathogenic microorganisms and the scope of involvement.

4. Cerebrovascular disease Internal carotid artery or cerebral arterial thrombosis or embolism, cerebral fat embolism, reducing or interrupting arterial blood flow, causing acute cerebral insufficiency and cerebral infarction in the arterial blood supply area, and secondary limitations or widespread Cerebral edema, cerebral aneurysm or arteriovenous malformation rupture and bleeding, subarachnoid hemorrhage, intraventricular hemorrhage, and cerebral vasospasm occur simultaneously, all of which are secondary to cerebral edema. 5. Sustained state of cerebral hypoxic epilepsy, chest trauma, dyspnea or asphyxia caused by different reasons, cardiac arrest, prolonged hypotension, shock, high altitude hypoxia, carbon monoxide poisoning and other pulmonary-derived encephalopathy Hypoxia accompanied by cerebral edema;

6. Exogenous or endogenous lead poisoning or systemic poisoning caused by other causes, often with diffuse cerebral edema.

7, various causes of cerebral metabolic disorders, systemic or local cerebral metabolic disorders, causing cerebral edema.

8. Radiation damage of the brain includes electromagnetic damage such as microwave, infrared, X-ray, -ray, -ray, fast neutron and so on.

Cerebral Edema Pathogenesis

The pathogenesis of cerebral edema is very complicated, with many related factors, blood-brain barrier, microcirculation disorder, cerebral ischemia and hypoxia, increased free radicals in the brain, changes in thromboxane A2 and prostacyclin, neurotransmitters and neuropeptides The change. Nerve cell calcium overload can affect the occurrence and development of cerebral edema.

1, blood-brain barrier dysfunction, the blood-brain barrier has the greatest relationship with cerebral edema. The blood-brain barrier is a barrier between the capillary cavity of the brain and the parenchyma of the brain, and is composed of the blood vessel lamellar layer of brain capillary endothelial cells, basement membrane, and stellate cells. The blood-cerebral spinal fluid barrier is mainly an occlusive band between the choroid plexus epithelium and endothelial cells. There is also a barrier between the cerebrospinal fluid and the brain parenchyma. Therefore, the material exchange between the brain and the blood must pass through this blood-brain barrier. Water can freely pass through the blood-brain barrier and the blood-cerebral spinal fluid barrier. The ability of electrolytes to pass through the blood-brain barrier and the blood-cerebral spinal fluid barrier is related to their fat solubility. Fat-soluble substances can easily pass through, but glucose can also pass through. During brain injury, brain tumor, and inflammation, the blood-brain barrier is destroyed, allowing plasma macromolecules to penetrate from the vascular cavity to the brain cell space. Therefore, the function and structural damage of the blood-brain barrier are considered to be the pathological basis of vascular cerebral edema .

2. Cerebral microcirculation disorders The normal blood flow of the brain and the microcirculation are extremely important for maintaining the normal physiological functioning of the brain.

Brain edema The blood flow of the brain is affected by systemic blood pressure, which varies with the pressure difference between cerebral arteries and veins. The cerebral blood vessels themselves have internal and central regulatory functions, which keep the cerebral blood flow stable within a certain range. During craniocerebral trauma, brain tumor, inflammation and other lesions, cerebral vessels spasm or paralysis, microcirculation dysfunction, increased venous pressure, cerebral congestion, cerebral hypoxia, resulting in cerebral metabolic disorders and cerebral edema. Therefore, cerebral microcirculation disorder is an important factor in the occurrence of cerebral edema.

3. Brain Cell Metabolism Disorders Nerve cells in the brain are structural and functional units that make up the nervous system, including the soma and protrusions. The fine structure of brain cells maintains the normal metabolism and function of brain cells. In brain cell metabolism, glucose metabolism is the most important aspect. Normally, aerobic metabolism is performed. When the brain is hypoxic, glucose metabolism in the cell metabolism becomes anaerobic, and it is broken down into lactic acid and pyruvate, which also releases energy. But due to the decrease in ATP, it is only 5% of normal aerobic metabolism. As a result, the function of the cell itself and the cell membrane is impaired. The sodium pump, calcium pump, and other ion pumps operate abnormally, and the sodium ion in the cell cannot be discharged. Increase. Water enters the cell from outside the cell to maintain the osmotic pressure balance inside and outside the cell, forming intracellular edema. The production of acidic substances in the cells increases the permeability of the cell membrane and aggravates cell edema.

4. Free radicals Free radicals in brain tissue. Oxygen radicals are a type of highly chemically active oxygen-containing groups, mainly composed of superoxide anions and hydroxide radicals. During brain injury, oxygen free radicals increase in the brain. During cerebral hemorrhage and cerebral ischemia reperfusion, free radicals also increase. Free radicals damage the cell membrane system, damage the blood-brain barrier, and cause brain edema.

5. Calcium overload of nerve cells In recent years, some studies have suggested changes in calcium overload of nerve cell membranes. Calcium overload in nerve cells is an important factor leading to cerebral edema. Calcium is an important factor to maintain the normal function of nerve cells. It plays an extremely important role in central nerve cell information transmission, neurotransmitter synthesis and release, axonal function of nerve cells, and blood-brain barrier function. When the calcium channel of the cell membrane is abnormally opened, extracellular calcium ions enter the cell, and intracellular calcium overload occurs, which causes a damaging effect. The adverse effects of calcium overload are wide: it can activate ATPase, protease, and phospholipase, increase ATP, cellular protein, and lipid catabolism, damage the cytoskeleton system and membrane system, and affect the expression and regulation of fast response genes in nerve cells. , Affects the cell DNA, causing serious damage to the cell. Can also cause cerebral vasospasm and cerebral hair cell vascular permeability changes. Therefore, calcium channel opening and nerve cell calcium overload have been regarded as one of the key links that cause brain edema.

6, increased intracranial venous pressure and other.

Cerebral Edema Pathophysiology

Cerebral edema is divided into vasogenic brain edema, cellular edema, osmotic edema and hydrocephalus.

1. The main cause of vasogenic brain edema is the damage and destruction of the blood-brain barrier, which results in increased capillary permeability, increased water exudation, and accumulation in the periphery of blood vessels and interstitial cells. At this time, because some protein substances penetrate into the extracellular fluid through the vascular wall with water, the osmotic pressure of the extracellular fluid increases, and the exudation of water from the vascular wall increases, leading to the continued development of brain edema and traumatic brain injury. Early cerebral edema is mainly vasogenic brain edema.

2.Cellular brain edema Cellular brain edema is a different pathogenic factor, which changes the internal and external environment of cells, hypoxia in brain tissue, affects neuronal cell metabolism, dysfunction of the cell membrane system, reduced mitochondrial adenosine triphosphate production, and sodium-potassium pump in nerve cell membrane Reduced activity of calcium and magnesium pumps

Brain edema To make sodium, potassium, calcium and other ion exchange disorders inside and outside nerve cells. These factors can cause intracellular edema. In this type of edema, the blood-brain barrier is not affected, the perivascular space and extracellular space are not significantly enlarged, the intracellular edema fluid does not contain protein, and the levels of sodium and chloride ions increase. Cellular edema is common in poisoning, severe hypothermia, cerebral ischemia, and hypoxia.

3. Osmotic brain edema Osmotic brain edema is caused by intracellular, extracellular fluid, and changes in electrolytes and osmotic pressure in the blood. Under normal circumstances, the internal and external electrolytes and osmotic pressure remain balanced and stable. This is suitable for normal physiological conditions and is regulated and restricted by hypothalamus and pituitary functions. Under pathological conditions, if brain damage affects the hypothalamic-pituitary axis function, reduced adrenocorticotropic hormone secretion, and increased release of antidiuretic hormone, blood osmotic pressure decreases, causing osmotic cerebral edema.

4, hydrocephalus hydrocephalus, also known as interstitial brain edema, is common in obstructive hydrocephalus. Obstructive hydrocephalus caused by different etiology causes the ventricular system to expand, especially the lateral ventricle, resulting in significantly higher intraventricular pressure than that in the brain tissue. A pressure gradient within the ventricle-brain tissue is generated. This significant difference in pressure gradient allows the intraventricular fluid to pass through the ventricle of the ventricle to the brain tissue around the ventricle, forming white matter brain edema around the ventricle.

Clinical manifestations of cerebral edema

Cerebral Edema Multiple Groups

People with brain tissue damage caused by intracranial or systemic disease.

Cerebral edema disease symptoms

Cerebral edema is a secondary pathological process caused by intracranial diseases and systemic system diseases. At the same time, cerebral edema often causes or exacerbates the increase in intracranial pressure, so the clinical manifestations often overlap with and exacerbate the symptoms of the primary lesion.

1. Symptoms of localized brain damage: Cerebral edema occurs mostly in local lesions such as local cerebral contusion or brain tumors, and around vascular disease. Common symptoms are exacerbation of epilepsy and paralysis, or motor aphasia caused by the spread of water quality and spread to the speech motor center. After brain injury, if the symptoms gradually worsen, more should be considered due to cerebral edema. Diffuse cerebral edema can be extended to whole brain due to local cerebral edema that is not controlled, or diffuse cerebral edema at the beginning, such as diffuse axonal injury.

2. Symptoms of increased intracranial pressure are headache, worsening vomiting, restlessness, lethargy and even coma. Fundus examination showed ocular edema. Early changes in vital signs, reduced pulse and breathing, and compensatory symptoms of elevated blood pressure, such as continued deterioration of cerebral edema and high intracranial pressure, can lead to

Brain edema Give birth to a hernia.

3. Other symptoms Brain edema affects the frontal lobe, temporal lobe, and anterior thalamus, which can cause mental disorders. In severe cases, consciousness and coma are caused. Increased intracranial pressure can also cause mental symptoms. Sometimes the body temperature increases moderately, cerebral edema affects the lower thalamus, which can cause symptoms of damage to the lower thalamus.

Cerebral Edema Disease Harm

Cerebral edema increases the intracranial pressure, which can aggravate cerebral edema and develop to a certain degree, which can cause functional and structural damage to the brain tissue. If it can not be diagnosed and treated in time, brain edema worsens, or it develops from localized to diffuse, which will cause serious harm to the brain, cause irreversible secondary pathological changes, and brain death will occur. This outcome is caused by widespread damage to brain tissue and severe brain stem damage secondary to cerebral hernia.

Cerebral edema examination diagnosis

The examination and diagnosis of cerebral edema can be prompted from the following aspects:

1. According to the clinical manifestations and processes of the disease, cerebral edema is mostly secondary to the primary disease. If the clinical symptoms are significantly worsened in a short period of time, local cerebral edema should be considered. Patients with cleavage quickly develop severe symptoms of increased intracranial pressure, coma, and more. For generalized or pancephalic edema. Application of dehydration treatment, if a diuretic effect appears, and the condition improves, it also indicates the presence of cerebral edema.

2. Intracranial pressure monitoring Intracranial pressure monitoring can display and record the dynamic changes of intracranial pressure, such as increased intracranial pressure. From the intracranial pressure curve combined with clinical process analysis, it can prompt the development and regression of cerebral edema.

3. CT or MRI CT or MRI scan directly prompts the most reliable diagnosis method of cerebral edema. The signs displayed on the CT image are around the lesion or white matter area, low-density areas of different ranges. The edema area is high signal and more accurate than the CT scan result.

Cerebral Edema Treatment

The principle of treatment of cerebral edema is to eliminate the cause and adopt comprehensive cerebral edema treatment, which complement each other.

Cerebral Edema Surgery

Eliminating the cause in a timely manner is the basis for the treatment of cerebral edema. Cerebral contusion, invasion, necrosis, liquefaction of brain tissue and subarachnoid hemorrhage, removal of intracranial hematomas, removal of bone fragments piercing the brain and restoration of depressed fractures, release of stimulation and compression of brain tissue, brain Tumor resection, non-traumatic intracerebral hematoma removal, etc., after clearing the cause, cerebral edema gradually subsided.

Cerebral Edema Other Therapies

1. An important measure to prevent cerebral edema during cerebral hypoxia is to keep the airway open. If hypoxemia and hypercapnia occur, assisted breathing and controlled ventilation are needed. Patients with common traumatic brain trauma continue to be in a coma. Immediate tracheotomy and sufficient oxygen are given to relieve the hypoxemia in the brain, and the condition improves. If the hypoxia is not relieved in time, its treatment will not be effective.

2.Treatment of cerebral edema and intracranial hypertension

1) Dehydration treatment. According to the condition, dehydration drugs are selected. Currently, 20% mannitol and furosemide are commonly used. Can be supplemented with concentrated serum albumin, good dehydration and antihypertensive effect.

2) Obstructive hydrocephalus causes hydrocephalus hydrocephalus, continuous drainage of the lateral ventricle, reducing the amount of cerebrospinal fluid, and the purpose of decompression and removal of cerebral edema.

3). There is still no unified opinion on the application of hormones and other drugs to brain cell damage. Free radical scavengers have a certain therapeutic effect.

4) Promote cerebral blood flow perfusion, improve microcirculation, and reduce blood-brain barrier permeability. Calcium channel antagonists such as nimodipine can be applied.

3.Promoting and improving brain metabolism Nimodipine acts as a calcium ion blocker to protect the cell membrane and inhibit calcium from entering the cell. Citicoline is an important coenzyme in the biosynthesis of lecithin in the brain. Lecithin is an important component of nerve cell membranes. Cerebrolysin, brain rehabilitation, Duxil and other drugs can promote cell redox, increase cell energy, and accelerate the repair of brain cell functions.

Prognosis of cerebral edema disease

Cerebral edema is a secondary pathological process. Systemic systemic diseases such as severe brainwashing vascular diseases, respiratory diseases, liver diseases, shock, toxic metabolic diseases, etc., cause changes in the internal environment of the body, causing ischemia and hypoxia in the brain tissue, and microscopic brain Disturbance of circulation and metabolism of brain cells may cause cerebral edema. So it is a question of universal significance. In neurosurgery, encephalopathy such as craniocerebral injury, intracranial space occupying lesions, inflammation, cerebrovascular disease, cerebral parasitic disease, and congenital brain diseases are often secondary edema, and secondary edema is often related to The process and prognosis of intracranial disease are more important. In the field of neurosurgery, if we can better understand the mechanism of brain edema and prevent and treat brain edema, we can achieve better results in the treatment of intracranial diseases. ^[1]

Cerebral Edema Disease Control Information

In 1905, Reichardt observed the incisional brain tissue samples and compared the differences between cerebral edema and brain swelling ^[2] . In the 1960s, Klatzo proposed the concepts of vasogenic brain edema and cytotoxic brain edema ^[3] . Fishiman first proposed interstitial cerebral edema ^[4] .