pediatric meningioma
Introduction
Introduction to pediatric meningioma Meningioma grows slowly and has a long course of disease, even for more than 10 years. It is the most common benign tumor in the brain. The tumor tends to grow very large, and the clinical symptoms (especially the symptoms of increased intracranial pressure) are not serious. Meningioma is rare in childhood, accounting for only 0.4% to 4.6% of childhood intracranial tumors. basic knowledge The proportion of illness: 0.001% Susceptible people: children Mode of infection: non-infectious Complications: hydrocephalus meningitis brain stem injury
Cause
Causes of pediatric meningioma
(1) Causes of the disease
There are two types of neuroepithelial tumors, one is formed by the interstitial cells of the nervous system (ie, glial cells), called gliomas; the other is formed by the parenchymal cells of the nervous system (ie, neurons), without a general name. Because of the pathogenic and morphological aspects, it is not possible to completely distinguish these two types of tumors, and gliomas are common. Therefore, neuronal tumors are included in gliomas, and tumors of neuroepithelial origin are the most common. Intracranial tumors account for about 44% of the total number of intracranial tumors. Meningeal tumors include meningeal endothelial cell tumors, mesenchymal non-meningeal endothelial tumors, primary melanocyte lesions, and tumors of unknown tissue origin.
(two) pathogenesis
Meningiomas belong to meningeal endothelial cell tumors, which may be derived from arachnoid villi or embryonic remnants, including 11 types, meningeal endothelial type, fibrous type, mixed type, sand granule type, vascular type, microcapsule type, secretory type, transparent cell type, Chordal-like, lymphoplasmic cell type, metaplastic type, the most common of which is the meningeal endothelial type, accounting for 53.5% of meningiomas.
Meningiomas are spherical and flat. They are more common in spherical shape, complete in surface or nodular, colored film, often with a "umbilical" connected to the dura mater; flat thickness often does not exceed 1 cm, widely distributed on the dura mater. It is more common in the bottom of the skull. The meningioma is rich in blood vessels. It is mainly supplied by the external neck and the intracervical (or vertebral basal) arteries. The tumor section is dark red, and there may be a milky yellow area with flaky lipid deposition. Sometimes see calcified grit, a few have cystic changes, meningioma tissue morphology has a variety of performance, but each type has a basic structure of meningioma, containing meningeal endothelial cell components, cell arrangement often retain arachnoid villi and arachnoid Some of the characteristics of the particles are swirling or concentric. The middle part of these concentric circles is prone to hyaline degeneration or calcification. The fibrous tissue, vascular tissue, fat, bone or cartilage and melanin are visible in the tumor tissue. The tumor malignancy is grade I. .
Prevention
Pediatric meningioma prevention
Refer to general tumor prevention methods, understand the risk factors of tumors, and formulate corresponding prevention and treatment strategies to reduce the risk of tumors. There are two basic clues to prevent tumors. Even if tumors have begun to form in the body, they can help the body to improve resistance. These strategies are described below:
1. Avoid harmful substances (promoting factors)
It is able to help us avoid or minimize exposure to harmful substances.
Some related factors of tumorigenesis are prevented before the onset, and many cancers can be prevented before they are formed. A report in the United States in 1988 compared the international malignant tumors in detail and proposed many external factors of known malignant tumors. In principle, it can be prevented, that is, about 80% of malignant tumors can be prevented by simple lifestyle changes, and traced back. In 1969, Dr. Higginson's research concluded that 90% of malignant tumors are caused by environmental factors," "Environmental factors", "lifestyle" refers to the air we breathe, the water we drink, the food we choose to make, the habits of activities, and social relationships.
2. Improve the body's immunity against tumors
Can help to strengthen and strengthen the body's immune system and cancer.
The focus of our current cancer prevention efforts should first focus on and improve those factors that are closely related to our lives, such as quitting smoking, eating properly, exercising regularly, and losing weight. Anyone who follows these simple and reasonable lifestyles can Reduce the chance of cancer.
The most important thing to improve the function of the immune system is: diet, exercise and control troubles. Healthy lifestyle choices can help us stay away from cancer. Maintaining good emotional state and proper physical exercise can keep the body's immune system at its best. Tumors and prevention of other diseases are equally beneficial. Other studies have shown that appropriate activities not only enhance the body's immune system, but also reduce the incidence of colon cancer by increasing the peristalsis of the human intestinal system. Here we mainly understand the diet in preventing tumorigenesis. Some questions.
Human epidemiology and animal studies have shown that vitamin A plays an important role in reducing the risk of cancer. Vitamin A supports normal mucosa and vision. It directly or indirectly participates in most of the body's tissue functions. Vitamin A is present in animal tissues. In the liver, whole eggs and whole milk, the plant is in the form of -carotene and carotenoids, which can be converted into vitamin A in the human body. Excessive intake of vitamin A can cause adverse reactions in the body and -carrot This is not the case with carotenoids, and the low vitamin A content in the blood increases the risk of malignant tumors. Studies have shown that those with low levels of vitamin A intake in the blood increase the likelihood of lung cancer, while those with low blood levels in smokers Levels of vitamin A ingestors have the potential to double lung cancer. Vitamin A and its mixture can help remove free radicals in the body (free radicals can cause damage to genetic material), and secondly stimulate the immune system and help differentiate cells in the body. Ordered tissue (while the tumor is characterized by disorder), some theories suggest that vitamin A can help early carcinogens Invasion mutated cells become reversed the occurrence of the normal growth of cells.
In addition, some studies suggest that supplementation with -carotene alone does not reduce the risk of cancer, but rather increases the incidence of lung cancer. However, when -carotene binds to vitamin C, E and other antitoxin substances, its protective effect. It is shown, because it can increase free radicals in the body when it is consumed by itself. In addition, there are interactions between different vitamins. Both human and mouse studies have shown that the use of -carotene can reduce 40% of vitamins in the body. At E-level, a safer strategy is to eat different foods to maintain a balanced vitamin to protect against cancer, as some protective factors have not been discovered so far.
Vitamin C, E is another anti-tumor substance that prevents the harm of carcinogens such as nitrosamines in food. Vitamin C protects sperm from genetic damage and reduces the risk of leukemia, kidney cancer and brain tumors in their offspring. Vitamin E can reduce the risk of skin cancer. Vitamin E has the same anti-tumor effect as vitamin C. It is a scavenger that protects against toxins and scavenges free radicals. The combination of vitamins A, C and E protects the body against toxins. Better than applying it alone.
At present, research on phytochemistry has attracted widespread attention. Phytochemistry is a chemical found in plants, including vitamins and other substances found in plants. Thousands of plant chemicals have been found, many of which have anticancer properties. The protective mechanism of these chemicals not only reduces the activity of carcinogens but also enhances the body's immunity against carcinogens. Most plants provide antioxidant activity that exceeds the protective effects of vitamins A, C, and E, such as a cup of cabbage. Contains 50mg of vitamin C and 13U of vitamin E, but its antioxidant activity is equivalent to the antioxidant activity of 800mg of vitamin C and 1100u of vitamin E. It can be inferred that the antioxidant effect in fruits and vegetables is far better than what we know. The effect of vitamins is strong, and no doubt natural plant products will help prevent cancer in the future.
Complication
Pediatric meningioma complications Complications hydrocephalus meningitis brain stem injury
Can be complicated by hydrocephalus, visual vision disorder, convulsions.
1. Meningitis: Post-cranial fossa tumors are more likely to develop meningitis after surgery than other parts of the tumor. It occurs more than 1 week after surgery. Patients continue to have high fever, neck resistance, cerebrospinal fluid leukocytosis, especially in the middle. The number of lobular nucleated cells increased significantly, but the repeated bacterial culture was negative. The elderly may have symptoms and signs that are not as obvious as those of young adults, but once they deteriorate, the prognosis is very poor. Therefore, in patients with craniotomy craniotomy, especially in patients with cerebellopontine angle meningioma, early, multiple, slow and appropriate amount of lumbar puncture release of cerebrospinal fluid is conducive to the recovery of cerebrospinal fluid circulation and reduce the occurrence of meningitis.
2, the latter group of cranial nerve injury: If the patient's posterior group of cranial nerves are pulled, clamped or postoperative adhesions, the postoperative patients are prone to drinking water cough, hoarseness, cough reflex, etc., at this time the patient is prone to inhalation Pneumonia, patients with postoperative dysfunction are more likely to occur. Once this complication occurs, it can prevent gastric tube feeding and nasal infusion. The intravenous infusion ensures the patient's energy and maintains the balance of water and electrolyte. It can be treated with nutrient nerve drugs to promote the recovery of neurological function of patients. Such as promoting the discharge of sputum.
3, brain stem injury: If the brain stem is excessively pulled during the process of resection of the tumor, electrocautery, excessive brain stem supply artery or direct electrocautery brain stem, it is easy to cause hemiplegia, and even respiratory and circulatory dysfunction. This complication should be based on prevention. If the treatment should be targeted, the patients with respiratory disorder have a poor prognosis. If it is only transient brain stem edema, the function may recover. If the infarction occurs, it is difficult to recover.
Symptom
Pediatric meningioma symptoms common symptoms growth slow intracranial pressure increased secondary optic atrophy hemianopia convulsion
In children with meningiomas, 5 to 14 years old is a good age, and infancy is extremely rare.
1. Clinical manifestations of children with meningioma
The most common symptoms are increased intracranial pressure, which can be manifested as headache, vomiting and optic disc edema, caused by obstructive hydrocephalus caused by lateral or posterior fossa tumors, and can also be caused by the tumor occupying effect, followed by Visual field of vision disorder, which may be caused by secondary optic atrophy caused by tumor oppression or obstructive hydrocephalus. The tumor in the lateral chamber may compress the deep radiation of the temporal lobe to cause isotropic hemianism. The cause of cranial nerves is the most common with facial nerves. 8% to 31% of children present with seizures, but the incidence of epilepsy is lower than that of adults.
2. Characteristics of children with meningioma
The characteristics of childhood meningioma and adult disease are as follows:
(1) Malignant is more common in adults: adult meningiomas are mostly benign, sarcoma-like changes are rare, and children with intracranial meningioma are more common than adults.
(2) located in the lateral ventricle triangle and posterior cranial fossa: adult meningioma occurs in the cerebral plane or sagittal sinus, while in childhood, the tumor is mostly located in the lateral ventricle triangle and posterior cranial fossa.
(3) combined with neurofibroma: more children with neurofibromatosis (about 20%).
(4) Endothelial and vascular endothelial cell types are more common: adult meningioma is more common in fibrosis and shale type, while children are more common in endothelial and vascular endothelial cell types.
(5) Tumors often grow faster: adult meningioma grows more slowly and has a longer course of disease; while children's tumors often grow faster, and tumors can grow enormously at the time of treatment.
(6) more than the dural non-adhesive: adult meningioma and adhesion to the dura mater; in children, tumors and dura mater non-adhesive are not a few, may be related to tumors from the arachnoid or pia mater.
(7) cystic changes and bleeding are common: cerebral calcification is rare in children, cystic changes and bleeding are more common.
(8) The recurrence rate is higher: the recurrence rate of children with meningioma is higher than that of adults.
Examine
Examination of pediatric meningioma
General laboratory tests are not specific.
Head flat film
(1) Localized bone changes: mostly bone hyperplasia, thickening of the inner plate, diffuse hyperplasia of the bone plate, needle-like radiation of the outer plate bone hyperplasia, and the incidence of localized thinning and destruction of the skull caused by meningioma Less, only about 10%.
(2) Increased vascular impression: visible thickening and distortion of the meningeal artery sulcus, the most common in the middle meningeal sulcus, the abnormal increase of local stenosis.
(3) tumor calcification: more common in granulous meningioma, calcification is denser, showing a mass of the entire tumor.
2. CT plain scan has a clear and high-density shadow on the edge, enhances the uniform coloration of the scanned tumor, strengthens obviously, and often has edema around it. CT examination can basically make a qualitative diagnosis of meningioma.
3. MRI can be equal or high signal on T1 weighted image. T2 weighted image is usually slightly higher signal or equal signal. MRI positioning diagnosis is better than CT, but the qualitative diagnosis of meningioma is often worse than CT.
4. Cerebral angiography is no longer used for qualitative localization diagnosis. It is only used to understand the blood supply of the tumor and the relationship with the surrounding blood vessels. At the same time, it can embolize the blood supply vessels of the tumor and provide convenience for surgical treatment.
Diagnosis
Diagnosis and diagnosis of pediatric meningioma
It is difficult to diagnose by clinical symptoms and signs alone. Combined with neuroradiology, meningioma showed uniform density or slightly higher density on CT, and uniform enhancement. In children's tumors, cystic changes and hemorrhage are more common and calcified. Rarely, the tumor is located in the brain parenchyma and does not adhere to the meninges and skulls. It is more common in adults. MRI examinations show more cortical-like T1 and T2 signal occupying, uniform enhancement, and there are signs of surrounding blood vessels, tumor sites and features. The performance is helpful for differential diagnosis. Some pediatric meningioma can be characterized by signal heterogeneity due to cystic necrosis.
Different from other meningeal tumors.
Head CT scan
A typical meningioma presents an isolated isobaric or high-density space-occupying lesion in an unenhanced CT scan. The base is wider, the density is uniform, the edges are clear, and calcification is visible in the tumor. After enhancement, the tumor was obviously enhanced, and the meningeal tail sign was seen.
Magnetic resonance scan
For the same patient, it is best to perform a comparative analysis of CT and MRI at the same time in order to obtain a more accurate qualitative diagnosis.
Cerebral angiography
Various types of meningioma are rich in vascular structure, DSA and superselective angiography, confirming tumor vascular structure, tumor rich in blood vessels, major cerebral vascular displacement, and the relationship between tumor and large dural sinus The openness of the sinus provides essential details. At the same time, angiography has also provided arteries for preoperative embolization and reduced intraoperative bleeding.
