Increased intracranial pressure in the elderly
Introduction
Introduction to increased intracranial pressure in the elderly 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. If a normal adult exceeds 1.96 kPa (200 mmH2O), it will increase intracranial pressure. When the elderly with increased intracranial pressure occurs in patients with malignant tumors, the majority are caused by intracranial metastases. basic knowledge The proportion of illness: 0.12% Susceptible people: the elderly Mode of infection: non-infectious Complications: cerebral edema, cerebral palsy, coma, hypertension
Cause
The cause of increased intracranial pressure in the elderly
Intracranial space-occupying lesions (20%):
Intracranial tumors, hematoma, abscesses, 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 brain edema. Causes an increase in intracranial pressure.
Intracranial infectious disease (20%):
Various meningitis, encephalitis, and brain parasitic diseases can stimulate excessive secretion of cerebrospinal fluid from the choroid plexus, and can cause cerebrospinal fluid circulation obstruction (obstructive and traffic hydrocephalus) and malabsorption; various bacteria, 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.
Head injury (15%):
Can cause intracranial hematoma and edema.
Cerebral hypoxia (15%):
Cerebral hypoxia caused by various causes such as asphyxia, anesthesia accident, CO poisoning, and certain systemic diseases such as pulmonary encephalopathy, status epilepticus, severe anemia, etc., can cause cerebral hypoxia, further causing angiogenic and cellular Toxic brain edema.
Poisoning lead, tin, arsenic and other poisoning (10%):
Some drug poisoning, such as tetracycline, vitamin A excess; self-poisoning such as uremia, hepatic encephalopathy, etc., can cause brain edema, promote choroid plexus secretion of cerebrospinal fluid, and can damage the autonomic regulation of cerebral blood vessels, and form a high cranial Pressure.
Endocrine dysfunction (10%):
Young women, obese people, especially menstrual disorders and pregnancy, are prone to benign intracranial hypertension, may be related to excessive estrogen, cerebral edema caused by excessive secretion of adrenocortical hormone, obes may be soluble with some steroids Adipose tissue does not play a role in causing relative adrenocortical hormones.
Pathogenesis
Brain metastasis is often secondary to the metastasis of the primary malignant tumor to the lungs. The tumor cells are then passed through the blood to the brain parenchyma, so it is often the third tumor site. However, the brain metastasis of lung cancer is often the first because the primary tumor is already in the lung. Two tumor foci, so the incidence of brain metastasis is significantly higher than other malignant tumors, and appears earlier, and even the first symptoms appear.
The distribution of brain metastases in the brain parenchyma is mainly in the cerebral cortex, which is related to the residual of the tumor cells through the internal carotid artery to the microvascular vessels with the smallest diameter, and the frequency of occurrence in each brain lobe and its brain parenchymal weight. Blood flow is closely related. For example, the cerebellum accounts for about 13% of the total brain weight, and the metastatic rate is about 15%. The on-screen brain parenchyma weight and metastasis rate are also about 80%, and the actual incidence of brain lobe brain metastasis. As shown in Figure 1, the basal ganglia, thalamic and brain stem metastases account for about 10%, and metastases in these sites often threaten life in a short period of time.
The brain is surrounded by hard materials such as skull and dura mater to maintain stability and is not easily damaged by external force. However, due to its poor elasticity, the volume of intracranial pressure is constant. To a certain extent, cerebrospinal fluid, cerebrovascular volume or extracellular fluid volume can change with each other. , can be buffered, maintain intracranial pressure stability, if the brain metastatic tumors increase in a long-term, or increase rapidly, or metastatic tumor compression venous return is blocked, or the brain canal pressure is affected by cerebrospinal fluid discharge and absorption Or arterial obstruction promotes hypoxia in brain cells, or metastasis directly damages the intima of the blood vessels, causing changes in the blood-brain barrier, and enhanced vascular permeability, resulting in increased water and ions in the extracellular space, and longitudinal diffusion along the white matter bundle. There is ipsilateral cerebral hemispheric edema, which affects the normal metabolism of the brain. The brain parenchyma can also be deformed by the metastatic lesion, the midline cerebral palsy is displaced, and the pressure in the supratentorial cavity can be fixed due to the fixation of the cerebellum and occipital foramen. When it rises sharply, it often induces cerebral palsy, such as sacral sulcus or cerebellar tonsil squeezing the brainstem and life center, leading to acute crisis, loss of consciousness, breathing and heart. Arrest caused irreversible damage and finally to death.
Prevention
Prevention of increased intracranial pressure in the elderly
1, active treatment of the primary disease: high blood pressure, high blood lipids, diabetes, coronary heart disease.
2. Middle-aged and elderly people over 40 years of age should have regular physical examinations once a year and find that the above diseases should be actively treated.
3. Maintain a good mental state and prevent emotional stress.
4, develop a good lifestyle, reasonable diet, cultivate their own cultural cultivation and life taste, so that the brain can be exercised to prevent the early onset of cerebral arteriosclerosis.
5, to prevent constipation, try to avoid doing violent actions, such as bending, bowing, lifting heavy objects, etc., to prevent brain blood pressure suddenly increased and cerebrovascular accidents.
6. Develop a good habit of regular bowel movements to prevent constipation and prevent excessive pressure in the abdominal cavity during defecation.
7. Usually try to avoid slamming, bowing, lifting heavy objects, etc., especially those with high blood pressure, to prevent sudden blood pressure in the brain is too high.
Complication
Elderly patients with increased intracranial pressure complications Complications, brain edema, cerebral palsy, coma
The main complications are cerebral edema, cerebral palsy, and coma.
Symptom
Symptoms of increased intracranial pressure in the elderly Common symptoms Intracranial hypertension increased intracranial pressure, ataxia, meningitis, diffuse headache, keratitis, unilateral headache, high intracranial pressure syndrome, brain metastasis
The clinical signs and symptoms of brain metastasis are closely related to the location of brain metastasis. This is due to the damage of tumor metastases, cerebral cortex or subcortical nucleus, conduction bundle, and tumor metastasis lesions and symptoms in different brain regions. As shown in Figure 2, if the brain metastasizes to multiple lesions, the clinical signs and symptoms may be correspondingly complex. Brain metastases and/or signs may appear before the primary tumor symptoms or signs, or may occur simultaneously or at comparable intervals. Later, the clinical manifestations of most cases (about 80%) appeared after the primary tumor symptoms. According to recent statistics, the median time between the two is about 17 months. Among them, lung cancer, melanoma and kidney cancer The interval between the breast cancer, colon cancer and sarcoma is longer, the brain metastasis is in the male, the lung, the gastrointestinal system and the urinary system are about 80% of the primary tumor; in women, the breast, Primary tumors such as lung, gastrointestinal system and melanoma account for about 80%; kidney cancer, ovarian cancer, osteosarcoma and breast cancer are often single-shot, while lung cancer, melanoma, seminoma are often Multiple metastases Clinically, it should also be vigilant. Brain metastases with a diameter of about 3 mm are often not easy to be found for examination. Brain metastases are often asymptomatic or physical signs in the early stage. They can only be found from regular special examinations, but careful medical history and detailed physical examination are still available. Helps to detect brain metastasis earlier.
Common symptoms and signs of brain metastases are headache, weak limbs, recognition ability or emotional disorder and epileptic seizures. Among them, unilateral headache, limb weakness or epileptic seizures are often localized symptoms of brain lesions; diffuse headache Recognition ability or emotional disorder and optic disc edema are often caused by cerebral edema, metabolic dysfunction or cerebrospinal fluid channel obstruction, the incidence of spontaneous symptoms of limb weakness is about 40%, and the positive rate of physical examination-induced signs can reach 66%; ataxia Can occur in cerebrospinal fluid circulation, can also be characteristic of cerebellar lesions, more advanced brain dysfunction including behavior, memory, speaking ability and proficiency of comprehensive functions (such as reading, writing, etc.) usually reported about 1 /3.
The most common acute episode of brain metastases is epileptic seizures. If there is a focal episode, there is a localized value of brain metastases. After epileptic seizures, there is a short limb weakness and weakness, which is mildly hemiplegia, such as epileptic seizure time. Long can present longer-lasting corresponding signs.
For patients with a history of malignant tumors, headaches or neurological symptoms or signs should be thoroughly examined to determine whether there is intracranial hypertension and brain metastasis; but for intracranial hypertension and brain metastases as the first symptom, it is easy to be misdiagnosed as primary brain Tumors and neglecting the comprehensive examination of negligence of real primary tumors, due to the decline of immune function of malignant tumors, easy to concurrent infectious diseases; in recent years, tuberculosis increased, and often complicated by cerebral tuberculosis and (or) tuberculous meningitis, worth Be alert and identify.
Examine
Examination of increased intracranial pressure in the elderly
ordinary inspection
Including three major routines, sputum exfoliated cell examination, coagulation function related examination, serological examination (select carcinoembryonic antigen, acid phosphatase, alpha-fetoprotein, lactate dehydrogenase, alkaline phosphatase, chorionic gonadotropin, Neuron-specific enolase, etc., positive, lateral X-ray, liver B-mode ultrasonography, and if necessary, gastric, intestinal or bronchoscopy, if superficial lymphadenopathy is found, biopsy can be used for pathology In order to find out the existence of the primary tumor and the extent and type of its invasion.
1.X line special inspection
Special examinations such as computed tomography (CT), magnetic resonance imaging (MRI) and digital subtraction (DSA) are the most important tests for determining the location of metastatic tumors and lesions in the brain. Other tests are only ancillary means, due to The changes of blood-brain barrier and blood tumor barrier, the contrast is enhanced after injection of contrast agent, and CT examination is performed for those suspected of brain metastasis. About 90% of brain metastases can show typical round shadows, often located in white matter and gray matter. In the junction, there is also a low-density area around it, which is caused by edema around the brain metastases. Most brain metastases are low-density areas before the contrast agent is strengthened, but the brain metastases of melanoma, choriocarcinoma and colon cancer are exceptions. It is often high density before the contrast agent is strengthened, and a thin layer examination can be used to find a lesion with a diameter of about 5 mm.
MRI can be observed from a variety of body levels, and different parameters (T1, T2, proton density) can be used to enhance the discovery of abnormal images and to have certain ability to distinguish the nature of their lesions. Because the brain and spinal cord contain fat (that is, rich in hydrogen protons) High composition, good imaging effect, and metastatic tumors contain low fat, so it is often used to determine the presence of brain metastatic tumors, and it is helpful to identify tumors, hemorrhage, hydrocephalus and cerebral edema.
DSA shows clear images of blood vessels in the brain. Metastatic tumors often form tumor coloring images due to blood supply, which is helpful for understanding changes in blood flow or interruption in the brain, and also provides information for treatment selection.
Regular examination of CT, MRI, is conducive to timely observation and early detection of brain metastases.
2. Lumbar puncture
Retain cerebrospinal fluid for routine and pathological cytology. Centrifugal sedimentation or use of filters can increase the positive rate. However, it is often necessary to repeatedly check; if necessary, send bacterial culture and related virological examination. Lumbar puncture often uses 22-gauge needle before puncture. Should be used for fundus examination, the puncture and drainage of the optic disc edema should be slow, leaving less cerebrospinal fluid, for the safety considerations can be dehydrated treatment.
Diagnosis
Diagnosis and identification of increased intracranial pressure in the elderly
Clinically, it must be differentiated from primary brain tumors and tuberculous meningitis.
