What is meningioma?Is a kind of origin in the meninges and meningeal gap derivatives, probably from dural fibroblasts and leptomeningeal cel
What is meningioma?
Is a kind of origin in the meninges and meningeal gap derivatives, probably from dural fibroblasts and leptomeningeal cells, but mostly from the arachnoid cells.
What is the incidence of meningioma?
The incidence rate of meningioma is about 2/10 million, which is only 20% of that of glioma, and the ratio of female to male is 2:3. The peak age is 30~50 years old
What happens with meningioma?
The occurrence of meningioma may be related to the change of internal environment and gene mutation, not a single factor. May be related to brain injury, radiation, virus infection and other factors associated with bilateral acoustic neuroma. The common feature of these factors is that they are likely to increase the rate of chromosome mutation, or cell division.
What are the clinical manifestations of meningiomas?
Meningiomas are benign mostly, with a complete capsule embedded in the brain parenchyma and dural compression close adhesion tumor through the pedicle constitute acceptable from external carotid artery blood supply has been corroded and adjacent skull hyperplasia or signs of meningioma with spherical or nodular growth in brain parenchyma, but often embedded within the cerebral hemisphere. This kind of tumor grows very slowly, the course of disease is long, so sometimes the tumor grows very big still can't appear symptom. Clinical manifestations depend on the location of the tumor. Located in the hemisphere, often causing headaches, seizures, hemiplegia and mental disorders. Elderly patients with epilepsy as the first symptom. Located in the skull base, the corresponding parts of the cranial nerve and brain involvement symptoms. Symptoms of intracranial hypertension usually occur later. The patient can because of chronic increased intracranial pressure due to binocular vision loss or even blindness. It is worth noting that the dummy area tumor grow big, and the brain has been unable to compensate when patients show increased intracranial pressure, the disease will suddenly deteriorated, even cerebral hernia in the short term.
What are some of the special examination of meningioma?
Most of the EEG were abnormal Q wave and slow wave, and the change of background EEG was slight. The more abundant blood supply, the more obvious the delta wave. X-ray plain film can be seen in the local skull plate thickening, diffuse proliferation of the bone plate, the outer plate bone hyperplasia was needle shaped radiation. Thickening of the meningeal artery sulcus of skull. The location of the proliferation of the skull is the center of the tumor. Transposition of vascular structure, tumor of the cerebral angiography confirmed that the tumor blood vessels, the main blood vessels of the brain and the degree of relationship, and large tumor dural sinus opening degree (decision intraoperative ligation) to provide detailed information necessary. CT examination showed that the tumor was located in the brain, the boundary was clear, the density was uniform, and there was extensive contact with the dura mater. MRI inspection can be seen, such as T1 or slightly lower signal, T2 signal can be equal signal, high signal (suggesting that the tumor is relatively soft texture), low signal (suggesting that the tumor is relatively hard texture), significantly enhanced after strengthening. For meningioma examination, mainly for CT and mri.
What are the treatment of meningiomas?
Because the majority of meningiomas are benign tumors, surgical resection is the main method, and the preferred method for recurrent meningiomas is still surgery. It can be used in combination with radiation therapy, cytokine therapy, gene therapy (mainly meningioma, is still in the research stage), and chemotherapy is very few (mainly for meningeal sarcoma can be considered chemotherapy), etc..
Whether meningioma needs treatment mainly depends on the location and size of meningiomas, whether there is pressure on the surrounding tissues, and whether there is an increase in intracranial pressure. If the meningioma is relatively small (such as 1cm) below, no obvious oppression on the brain and cranial nerves, can be observed, it is recommended to review once a year, with or without changes. Meningioma with diameter less than CrN feasible x- knife or gamma knife treatment if the tumor is relatively large, around the brain and cranial nerves were oppressed, or evidence of raised intracranial pressure patients as long as there is no surgical contraindication to surgery, recommended surgical resection. Because the tumor receives a double blood supply from the internal carotid artery and the bleeding is more complete excision should include the invasion of the dura mater and adjacent skull
1 total resection of tumor, reduce the incidence of nerve injury: with the in-depth study of micro neuroanatomy, various surgical approach has been relatively mature, the key is how to surgical resection of tumor. Problems have the following problems: 1 meningioma tumor around the important blood vessels and nerve, caused by tumor excision; tough texture, not all cut; the blood supply of the tumor is extremely rich, resulting in the risk of surgery; tumor invasion and the dura and its formation, is not easy to deal with. In view of the above problems, it is necessary to develop individualized operation scheme, to refine the operation technique, and to select the convenient and delicate surgical instruments, and strive to achieve the Simpson level. In this way, the postoperative recurrence of tumor can be greatly reduced. Of course, it is also important to assess the risk of tumor resection and nerve injury, which requires highly experienced physicians to assess.
2 the right choice of stereotactic radiosurgery or radiotherapy to control the tumor: radiotherapy including photon beam and proton beam therapy or sub external irradiation treatment. Most of the medical center using an improved linear accelerator system or gamma knife to patients. Radiation therapy can be used to replace surgery in small tumors that are far from important structures. This kind of meningioma is mainly the location of the tumor is relatively deep, the tumor volume is small (usually less than 3cm) for brain tissue and cranial nerve no obvious symptoms of oppression. This method is mainly used for small residue postopcrative, or small lesions and elderly patients, to consider radiosurgery treatment in a timely manner. It is also an important measure to prevent the recurrence of the tumor, which can not be treated by conventional radiotherapy.
For radiotherapy, surgery can not in all, but after decompression of radiation therapy (mainly for gamma knife treatment), can control or reduce tumor recurrence; or the patient can not tolerate surgery, can be directly considered for radiotherapy (without increased intracranial pressure and cranial nerve or brain tissue compression). For patients with subtotal resection of grade WHO meningiomas, postoperative radiotherapy is often required. For patients with grade WHO and grade III meningiomas, the current standard of care is postoperative radiotherapy, regardless of the extent of surgical resection. This is because of the relatively high postoperative recurrence rate of these high-grade tumors.
The gamma knife treatment of meningiomas is to control the growth of tumor, the treatment is based on: 1 meningioma is a benign tumor, slow growth, with low dose treatment, there is plenty of time to slow tumor necrosis; the meningioma in CT or MRI development easy and clear boundaries, for dose calculation, and can effectively protect the the surrounding tissue; the meningioma rely on image diagnosis can be made, most do not need to judge the pathology; the elderly disease incidence rate is high, not suitable for surgical treatment.
That a lot of experience in treating cerebral convex meningioma, especially parasagittal meningiomas, even smaller, but also prone to edema, serious long-term radiation reaction, should be the preferred surgical treatment, the residual part for gamma knife treatment. Meningioma of the cranial base radiation reaction is lighter, larger volume can be used at the time the gamma knife treatment. For elderly patients, due to the slow growth of the tumor itself, can be used to treat low doses, the purpose of controlling the growth of the main, that is, the so-called "coexistence of human tumors.
3 other therapies: cytokine therapy. Such as the application of Suramin can interfere with cell signal transmission, the application can reduce the proliferation of meningioma cells. There are other applications of IL-1 beta, IL-6 and IFN and other treatment of meningiomas. Gene therapy. If the adenovirus gene was introduced into the meningioma supply vessels, the expression of the gene was observed. The main research focus on NF-2 and p53 genes. Chemotherapy, the effect still needs further exploration. The main point for meningeal sarcoma can be considered chemotherapy. The hormone therapy. Some hormones are associated with the development and progression of meningiomas. The use of anti progesterone drugs, but the results vary. A recent study found that hydroxyurea drugs can cause tumors and recurrent unresectable meningiomas decreased, but these also need further evaluation.
Meningeal sarcoma is a malignant type of meningioma which accounts for about 5% of the total number of meningiomas. It is easy to recur after resection and the prognosis is poor