Posterior fossa ependymoma
Introduction
Introduction to posterior fossa ependymoma Ependymoma (ependymoma) occurs in the ependymal cells of the ventricles, accounting for 5% to 10% of primary tumors in the central nervous system of children. Occurs in the posterior fossa, about 60%, more common in children under 5 years old. basic knowledge The proportion of illness: 0.0003% Susceptible people: good for children under 5 years old Mode of infection: non-infectious Complications: epilepsy
Cause
The cause of posterior fossa ependymoma
Causes:
There are two types of neuroepithelial tumors, one is formed by the interstitial cells of the nervous system (ie, glial cells), called gliomas, and 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 approximately 44% of the total number of intracranial tumors, and ependymoma occurs in the ependymal cells of the ventricles.
Pathogenesis:
Ependymoma originates from the primitive ependymal epithelium, so it occurs in the ventricular system. The fourth ventricle is the most common site of development. It can invade the cerebellar hemisphere and ankle in the dorsal side. The posterior part of the ventricle, which protrudes into the spinal canal through the large hole of the occipital sac; or the cerebral cerebral nerve is formed by the cerebellopontine angle of the cerebellopontine through the lateral ventricle of the fourth brain (luschka hole). The tumor is often pink, nodules The shape of the intraventricular growth tends to be clear, but the growth at the base or in the brain is invasive, the tumor texture is hard, and the tumor cells often fall off the subarachnoid space to form a disseminated metastasis.
Prevention
Prevention of ependymoma of the posterior cranial fossa
Refer to the 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 as follows:
1. Avoid harmful substances (promoting factors): It can 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.
Promote the body's immunity against 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, maintain good emotional state and appropriate physical exercise can make the body The immune system is at its best, and it is also good for preventing tumors and preventing other diseases. In addition, 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 some of the problems of diet in preventing tumors.
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
Complications of posterior fossa ependymoma Complications
On-screen tumors may be associated with epilepsy and local brain damage symptoms. Under-the-slice tumors may have nystagmus, poor cerebellar movement and other symptoms of cerebellar damage and low-level cranial nerves (VI, VII, VIII, IX, X), and vomiting. Common, can form a spread transfer.
Symptom
Post-cranial fossa ependymoma symptoms common symptoms ataxia increased intracranial pressure increased muscle tone gait instability edema diplopia nystagmus
Cerebrospinal fluid circulation obstruction can occur headache, vomiting, optic disc edema and other signs of increased intracranial pressure, but the early vomiting symptoms of the disease are more related to tumor stimulation of the medullary vomiting center of the fourth ventricle, the brain stem compression symptoms appear early and heavy The characteristics of the disease can be manifested as cerebral nucleus or medullary nucleus of the nucleus (such as facial paralysis, double vision, swallowing ruminant, etc.) and weakened muscles, tendon reflexes and other pyramidal tract signs, some patients may be affected by cervical nerve roots After the pressure appears neck pain and forced head position, backward growth and compression of the cerebellar foot or its ventral side, there may be nystagmus, gait instability, ataxia, decreased muscle tone and other cerebellar damage signs, some children may be due to Tumor implantation in the spinal canal showed signs of spinal cord damage.
In the early stage of the disease, the symptoms of the fourth ventricle cerebral nucleus and the signs of pyramidal tract are shown. When cerebellar damage and cranial hypertension occur, the possibility of ependymoma should be considered.
Examine
Examination of posterior fossa ependymoma
Laboratory tests have no specific performance and should be performed as an auxiliary test.
1. Skull X-ray film: more common signs of increased intracranial pressure, partial visible posterior cranial fossa calcification (2.8%).
2. CT examination: the fourth ventricle is equal or slightly densely occupied, some low-density cystic changes and calcification are more common, the tumor boundary is clear, easy to strengthen, but more uneven.
3. MRI: long T1 long T2 lesions with uneven signal, nodular, sagittal position is conducive to distinguish between the tumor and the fourth ventricle, the position of the cerebellum and the length of the extension into the spinal canal.
Diagnosis
Diagnosis and diagnosis of ependymoma of the posterior cranial fossa
To differentiate from pediatric cerebellar astrocytoma and medulloblastoma, the sequence of clinical symptoms and characteristic imaging changes make identification difficult.
