Pediatric optic glioma
Introduction
Introduction to pediatric optic glioma The incidence of optic glioma (opticglioma) is relatively low and is more common in children. About one-third of tumors are confined to one side of the optic nerve, while two-thirds of patients have an optic chiasm, hypothalamic, three-ventricle, and optic tract invasion. basic knowledge The proportion of illness: 0.002% Susceptible people: children Mode of infection: non-infectious Complications: hydrocephalus, precocious puberty
Cause
Pediatric optic glioma etiology
(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.
(two) pathogenesis
The tumor boundary seen by the naked eye is often smoother and has a "false envelope", and the area of actual tumor cell infiltration has far exceeded the boundary shown by the "false envelope", which is often infringed by superficial glioblastoma. And penetrate the cerebral cortex and adhere to the dura mater, the shape of the tumor is irregular, there are tumor areas, necrotic areas and hemorrhage areas, cysts can form, the tumor tissue is soft and brittle, and blood supply is abundant. The characteristics of the tumor are:
1 a variety of histological morphology of tumor cells.
2 tumor cell nuclear fission is quite common.
3 blood supply is abundant.
4 interstitial fibrosis derived from the adventitia.
Growth characteristics:
1 Glioblastoma has a tendency to grow along the nerve bundle in the white matter to a distant place.
2 After the tumor invades the ventricle, it can be transferred through the cerebrospinal fluid.
3 multi-centered growth, there are several independent tumor centers from 4.9% to 20%.
The degree of malignancy of the tumor is grade IV. The pathological type of the tumor is mostly low-grade astrocytoma, often hairy cell type. The diversity of the natural course of the tumor makes the evaluation of the treatment effect very difficult. Some scholars will use the preoperative MRI performance. Divided into 3 categories:
1 visual cross front type;
2 diffuse optic chiasm;
3 visual cross-hypothalamic exogenous type to guide surgical treatment.
Prevention
Pediatric optic glioma prevention
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 optic glioma complications Complications
Concurrent hydrocephalus, diencephalic syndrome, precocious puberty, etc.
Symptom
Pediatric optic glioma symptoms Common symptoms Slow growth visual impairment Ocular eye nystagmus Vision Deficit Precocious strabismus Drowsiness edema Urine collapse
1. Pre-intersection type often shows progressive vision loss and exophthalmos. In infants and young children, nystagmus is often used. The oblique is regarded as the first symptom. The fundus examination can reveal the expansion of the optic disc vein and the edema of the optic disc. When the disease course is long, the optic disc can be atrophied. .
2. Diffuse optometry is characterized by decreased visual acuity and bilateral visual field defects. Endocrine symptoms and hydrocephalus are rare. Such children have many other manifestations of neurofibromatosis (such as skin pigmentation). .
3. The chiasm-hypothalamic clinical symptoms are mostly age-related:
(1) Less than 2 years old: Children younger than 2 years old are often characterized by hydrocephalus, delayed development, vision loss and diencephalic syndrome.
(2) 2 to 5 years old: 2 to 5 years old children, endocrine disorders are the most common, can be expressed as precocious puberty or growth retardation, about half of the children have visual impairment.
(3) Children: Children with younger age are most likely to have visual impairment and damage to the lower part of the hypothalamus (sleepiness, diabetes collapse, diencephalic epilepsy, etc.).
Examine
Examination of pediatric optic glioma
General routine examination showed no abnormalities, and endocrine disorders were seen in children with chiasm-hypothalamic type.
1. Skull X-ray film
It can be seen that there is an enlargement of the optic nerve hole, and the saddle is "pear-shaped or gourd-shaped", which affects the increase of intracranial pressure when cerebrospinal fluid circulation occurs.
2.CT
Type I and II have more optic nerve thickening, lesions are of equal density, irregular enhancement, few calcifications, cystic changes are rare; visible anterior cleft, saddle nodule bone resorption and optic nerve hole enlargement, type III It shows the occlusion of the upper saddle pool, the density of the saddle area, and a small number of obstructed interventricular pores that enlarge the lateral ventricle.
3.MRI
It can often clearly show the displacement of the anatomical structure and the optic nerve, the thickening of the optic chiasm, the appearance of the pear-like appearance, the front small and the thick, as shown in Figure 1, the signal intensity has no characteristic changes, the preoperative MRI performance can be divided into Category 3:
(1) Pre-cross-sectional type: The pre-optic pre-existing type is characterized by fusiform thickening of the internal optic nerve, while the intracranial visual cross is not invaded, and bilateral lesions are occasionally seen in patients with neurofibromatosis.
(2) diffuse optic chiasm: diffuse optic chiasm is most common in children with neurofibromatosis, manifested as diffuse thickening of the optic chiasm, which can invade the optic nerve or optic tract before and after growth.
(3) Optic chiasm-hypothalamic exogenous type: the chiasm-hypothalamic exogenous type is unique, and the chiasm-hypothalamic exogenous mass is more common.
In order to guide the surgical treatment, it was found that the morbidity and mortality of the latter two were higher than the former.
Diagnosis
Diagnosis and diagnosis of pediatric optic glioma
diagnosis
Children with painless, non-pulsating exophthalmos, accompanied by progressive decline in vision, should cause high attention to the disease, should be performed neuro-ophthalmology and neuroradiology, some patients can have endocrine disorders and hypothalamic compression Seek for the first symptom.
Differential diagnosis
Tumor type I and II should be identified with the following saddle area: sacral meningocele; retinoblastoma; teratoma; tibia bone fiber dysplasia, type III need to be differentiated from germ cell tumor or craniopharyngioma .
