Increased intracranial pressure

Introduction Normal people have a certain pressure in the skull, called intracranial pressure (referred to as intracranial pressure), which usually refers to the pressure measured by the lumbar puncture and the tube with a certain inner diameter in the horizontal position and the slack body. It is called cerebrospinal fluid pressure. In the lateral position, when the average cerebrospinal fluid pressure of an adult exceeds 1.96 kPa (equivalent to 200 mm water column), it is called an increase in intracranial pressure. Increased intracranial pressure is a group of syndromes common to many diseases that are common in clinical practice. Any lesion that can cause an increase in the volume of the cranial cavity can cause an increase in intracranial pressure.

Cause

Common causes are:

1. Intracranial space-occupying lesions:

Intracranial tumors, hematoma abscess cysts, granuloma, etc., can occupy a certain volume in the cranial cavity, and can block the circulation pathway of cerebrospinal fluid, affecting its circulation and absorption. In addition, the above lesions can cause secondary cerebral edema, resulting in increased intracranial pressure.

2, intracranial infectious diseases:

Various meningitis encephalitis and brain parasitic diseases can stimulate excessive secretion of cerebrospinal fluid in the choroid plexus, and can cause cerebrospinal fluid circulation obstruction (obstructive and traffic hydrocephalus) and malabsorption; various bacterial fungi, viruses, Parasite toxins can damage brain cells and cerebral blood vessels, causing cytotoxicity and vasogenic cerebral edema; inflammation, parasitic granuloma can also play a role in occupying a certain space in the cranial cavity.

3, head injury:

Can cause intracranial hematoma and edema.

4, brain hypoxia:

Cerebral hypoxia caused by various causes such as asphyxia, anesthesia accident, CO poisoning, and certain systemic diseases such as pulmonary encephalopathy, epilepsy persistent severe anemia, etc., can cause cerebral hypoxia, further causing angiogenic and cytotoxicity Brain edema.

5, poisoning:

Lead, tin, arsenic and other poisoning. Some drugs are poisoned, such as tetracycline, vitamin A excess. Self-poisoning such as uremia, hepatic encephalopathy, etc., can cause brain edema, promote the secretion of cerebrospinal fluid from the choroid plexus, and can damage the autonomic regulation of cerebral blood vessels, and form high intracranial pressure.

6, endocrine dysfunction:

Young women, obese people, especially menstrual disorders and pregnancy, prone to benign intracranial pressure may be associated with excessive estrogen and excessive cerebral edema caused by adrenocortical hormone secretion. Obese people may be related to the fact that some steroids are not soluble in adipose tissue and cause relative adrenocortical hormones.

an examination

Related inspection

Cerebrospinal fluid pupil positioning blood routine intracranial pressure monitoring cerebral angiography head flat film

Clinical manifestations of increased intracranial pressure:

(1) Headache: This is one of the most common symptoms of increased intracranial pressure. The degree is different. It is heavier in the morning or evening. The part is mostly in the forehead and ankle. It can radiate from the neck occipital to the eyelid. The degree of headache is progressively aggravated with an increase in intracranial pressure. Headaches often worsen when forced, coughed, bent or bowed. The nature of headache is more common with pain and tearing pain.

(2) Vomiting: When the headache is severe, it may be accompanied by nausea and vomiting. Vomiting is jetting and is prone to occur after a meal, sometimes leading to water and electrolyte disturbances and weight loss.

(C) optic disc edema: This is one of the important objective signs of increased intracranial pressure. The performance of the optic disc is congested, the edges are blurred, the central depression disappears, the optic disc is uplifted, and the veins are engorged. Early vision medical education of optic disc edema|There is no obvious change in the collection of the net. If the optic disc edema persists for a long time, the optic disc is pale, the vision is diminished, and the visual field is narrowed, which is called secondary atrophy of the optic nerve. At this time, if the increase in intracranial pressure is lifted, vision recovery is not ideal, and even worse and blindness continues.

an examination:

A comprehensive detailed medical history and careful neurological examination can be found that many intracranial diseases have some focal signs and symptoms before causing an increase in intracranial pressure, which can be initially diagnosed. When there are three main signs of optic disc edema, headache and vomiting, the diagnosis of increased intracranial pressure is roughly certain. However, because the patient's self-conscious symptoms are often earlier than the optic disc edema, the following auxiliary examinations should be performed in time to diagnose and treat as soon as possible.

1. Computed tomography (CT): At present, CT is the first choice for the diagnosis and diagnosis of intracranial space-occupying lesions. It not only provides a diagnosis of the majority of space-occupying lesions, but also contributes to qualitative diagnosis. CT is non-invasive and easily accepted by patients.

2, magnetic resonance imaging (MRI): in the case of CT can not be diagnosed, MRI can be further tested to facilitate the diagnosis. MRI is also non-invasive, but the cost of the examination is high.

3, cerebral angiography: mainly used for cases of suspected cerebrovascular malformations or aneurysms. Digital subtraction angiography (DSA) not only improves the safety of cerebral angiography, but also makes the image clear and improves the detection rate of the disease.

4, skull X-ray film: When the intracranial pressure is increased, it can be seen that the skull joint separation, finger pressure marks increased, saddle back bone sparse and saddle enlargement.

5, lumbar puncture: lumbar puncture pressure on the intracranial space-occupying lesions patients have a certain risk, sometimes triggering cerebral palsy, it should be carried out cautiously.

6. Radioactive 99mTc scan: It can reflect the anatomical structure of the brain section and the functional activities of the cells.

Differential diagnosis

Symptoms of increased intracranial pressure need to be identified as follows:

(1) Brain injury:

Brain contusion, cerebral edema, and intracranial hematoma caused by any cause of craniocerebral injury can increase intracranial pressure. Increased intracranial pressure can occur in the early stage of acute severe craniocerebral injury. A small number of patients can appear later, such as chronic subdural hematoma. After craniocerebral injury, patients often quickly enter a coma with vomiting. Hematoma in the brain can occur due to hemiplegia, aphasia, and seizures depending on the location. Cranial CT can directly determine the size, location and type of intracranial hematoma, as well as intraventricular hemorrhage that cannot be diagnosed by cerebral angiography.

(2) Cerebrovascular diseases:

Mainly for hemorrhagic cerebrovascular disease, hypertensive cerebral hemorrhage is most common Generally, the onset is more urgent, and the increase in intracranial pressure is reached within 1-3 days. Patients often have varying degrees of disturbance of consciousness. It is characterized by headache, dizziness, vomiting, limb paralysis, aphasia, incontinence and so on. There is often a significant increase in blood pressure at the time of onset. Most patients have positive meningeal irritation. Cerebrospinal fluid pressure is increased and often bloody. Brain CT can determine the size of the bleeding and the location of the bleeding.

(3) Hypertensive encephalopathy:

Hypertensive encephalopathy refers to a sudden increase in blood pressure that causes acute and comprehensive brain dysfunction. Common in acute hypertension, acute and chronic nephritis or eclampsia, occasionally due to pheochromocytoma or taking monoamine oxidase inhibitors while taking tyramine-containing foods, lead poisoning, Cushing's syndrome. Frequently, the blood pressure suddenly increased significantly to 33.3/20 kPa (250/150 mmHg), and the increase in diastolic blood pressure was more significant than systolic blood pressure. Symptoms of increased intracranial pressure such as severe headache, nausea, vomiting, and neck stiffness often occur at the same time. Neuropsychiatric symptoms include visual impairment, hemiplegia, aphasia, epilepsy-like convulsions or limb muscle rigidity, and disturbance of consciousness. The fundus may have hypertensive fundus, retinal artery spasm, and even retinal hemorrhage, exudate, and optic nerve head edema. CT examination showed cerebral edema and narrowing of the ventricles. The electroencephalogram shows diffuse slow waves, loss of alpha rhythm, and no response to light stimulation. Generally do not do lumbar puncture examination.

(4) Intracranial tumors:

It can be divided into primary intracranial tumors and metastases that are metastasized from malignant tumors in other parts of the body to the brain. The common feature of intracranial pressure caused by brain tumors is the chronic progressive typical intracranial pressure. Although the symptoms may be slightly up and down during the course of the disease, the general trend is gradually increasing. A small number of patients with increased chronic intracranial pressure can suddenly turn into an acute attack. According to the tumor growth site can be accompanied by different symptoms, such as changes in visual field of vision, pyramidal tract damage, seizures, aphasia, sensory disturbances, mental symptoms, cerebellopontine angle syndrome. Head CT can identify the location and nature of tumor growth.

(5) Brain abscess:

There are often primary infections, such as otogenic, nasal or traumatic. At the beginning of blood supply, there may be systemic symptoms of acute inflammation, such as high fever, chills, meningeal irritation, increased white blood cells, blood sedimentation, and increased lumbar vertebrae. However, after the abscess maturity period, the above symptoms and signs disappeared, only the increase of chronic intracranial pressure, with or without focal neurological signs. The course of brain abscess is generally shorter and the mental retardation is more serious. CT scans often show a circular or oval density that reduces shadows. After the contrast agent is injected, the edge image is significantly enhanced. The thin, smooth ring density increases the shadow, and the low-density brain edema around the abscess is more pronounced.

(6) Infectious diseases of the brain:

Brain infection refers to inflammatory diseases of the brain and meninges caused by bacteria, viruses, parasites, rickettsia, and spirochetes. Acute or subacute intracranial pressure increased, a small number of manifestations of chronic intracranial hypertension, often with symptoms of infection, such as fever, general malaise, increased blood and so on. Some cases have conscious disturbances, confusion, myoclonus and seizures. In severe cases, they develop into deep coma within a few days. In some cases, mental disorders may occur, manifested as sluggishness, decreased speech movements, slow response or anxiety, incoherent speech, frequent interruptions in memory and orientation, and even illusions, hallucinations, delusions, and embarrassment. The symptoms of the nervous system are various, and the important features are frequent focal symptoms such as hemiplegia, aphasia, bilateral oblique deviation, partial epilepsy, and involuntary movement. Others may have neck stiffness, meningeal irritation and so on. Cerebrospinal fluid often has inflammatory changes, such as cerebrospinal fluid leukocytosis, increased protein, or decreased sugar or chloride, positive complement test. There is an inflammatory change in the head CT.

(7) Hydrocephalus:

Due to various reasons, the cerebrospinal fluid in the ventricular system is increasing, and the brain parenchyma is correspondingly reduced. When the ventricle is enlarged and accompanied by increased intracranial pressure, it is called hydrocephalus, also known as progressive or high-stress hydrocephalus. The clinical manifestations are different at different times. Infant hydrocephalus is mainly manifested by the rapid increase of the head in the weeks or months after the birth of the baby. At the same time, the portal is enlarged and raised, the tension is high, the cranial suture is separated, the head shape is rounded, and the skull is thin and soft. The head percussion is "broken pot sound", the severe one has a sense of tremor when percussion, and the frontal scalp vein is engorged. The skull is very large and the skull is small. The two eyes are turned down to reveal the sclera above. The child is weak, slow, irritating, and difficult to lift the head. There may be symptoms such as seizures, nystagmus, ataxia, increased muscle tone in the extremities or palsy. Ventricular angiography showed a marked enlargement of the ventricles. CT examination can detect tumors, accurately observe the size of the ventricles, and show the degree of edema around the ventricles.

(8) Increased benign intracranial pressure:

Also known as "pseudo-brain tumor", the patient has only symptoms and signs of increased intracranial pressure, but no space-occupying lesions exist. The cause may be arachnoiditis, otogenic hydrocephalus, venous sinus thrombosis, etc., but often can not be found. Clinical manifestations, in addition to increased chronic intracranial pressure, generally no focal signs.

(9) Other:

The increase in intracranial pressure caused by systemic diseases is also quite common in clinical practice. Such as infection with toxic encephalopathy, uremia, water and electrolytes and acid-base balance disorders, diabetes coma, hepatic coma, food poisoning. The progression of these diseases to the severity can lead to increased intracranial pressure. A clear diagnosis can be made in combination with the history of the disease and the systemic examination.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.