petrous clivus meningioma
Introduction
Introduction to rock bone slope meningioma Anatomically, the rock-bone slope area refers to the area enclosed by the sphenoid bone, the tibia and the occipital bone. These bones constitute the middle and posterior cranial fossa of the skull base. The meningioma of the rock slope is a meningioma that occurs in this area. basic knowledge The proportion of illness: 0.0008% Susceptible people: no special people Mode of infection: non-infectious Complications: facial paralysis cerebrospinal fluid leakage hydrocephalus epilepsy
Cause
Cause of meningioma
Meningiomas can be derived from arachnoid cells, fibroblasts and blood vessels of the meninges. Most of them are arachnoid cells derived from spider webs. Meningiomas generally grow slowly. The naked eye is mostly round, lobulated or irregular. The texture is tough or hard, the boundary is clear, and the surrounding brain tissue has a depressed depression or notch. The tumor base is located on the slope, the tip of the rock or the rock, and can cause local bone destruction. The microscope is mainly divided into the following types. :
1 meningeal endothelial meningioma;
2 fibroblast type;
3 transitional type;
4 vascular type, including vascular type, hemangioblast type and vascular epithelial cell type three subtypes);
5 malignant meningioma and so on.
Prevention
Rock bone slope meningioma prevention
Pay attention to the details of life, don't eat too irritating food.
Complication
Complications of meningioma Complications, facial paralysis, cerebrospinal fluid, hydrocephalus, epilepsy
After surgery, the following complications may occur:
1. Multi-brain nerve and brain stem injury Spetiler reported 46 cases of rock-slope meningiomas. The postoperative facial paralysis accounted for 30%, the nerve paralysis was 2%, the hearing decreased by 9%, and the hemiplegia was 1%. Another literature reported that 50% had Cerebral nerve damage symptoms, the latter group of cranial nerve palsy can cause difficulty in breathing, etc., should be tracheotomy.
2. Postoperative cerebrospinal fluid leakage cerebrospinal fluid leakage is the main complication after the labyrinth approach and the labyrinthine approach. The incidence rate is high. Spiterer reports that it is about 13%. Once cerebrospinal fluid leakage occurs, the waist can be drained and the cerebrospinal fluid is released. Local compression dressing, if it can not self-heal, surgery can be repaired, or the lumbar puncture can be used to prevent cerebrospinal fluid drainage after operation, which can prevent postoperative cerebrospinal fluid leakage, with an average of 1 week and a maximum of 2 weeks.
3. Intraoperative and postoperative bleeding, intracranial infection is equivalent to general surgery.
4. Concurrent hydrocephalus due to postoperative cerebrospinal fluid circulation disorders, combined with hydrocephalus, ventricular enlargement can be considered ventriculo-peritoneal shunt.
5. Epilepsy and aphasia caused by compression or injury of the left temporal lobe, during surgery should pay attention to avoid the operation of temporal lobe injury, pay attention to protect Labbé vein, postoperative anti-epileptic drugs.
Symptom
Symptoms of meningioma on the slope of the rock bone Common symptoms Ataxia, increased intracranial pressure, hydrocephalus
The rock-slope meningioma is a benign tumor with a long history of more than 2 years, with an average of 2.5 to 4.5 years. Due to the close proximity of the tumor, the cranial nerve, the basilar artery and its branches, the cerebellar hemisphere, and the brain stem are important structures. The clinical manifestations are more complicated. The symptoms of nervous system damage vary according to the location of the tumor and the direction of growth. The main manifestations are:
1. Headache headaches are mostly limited to the top of the pillow, but also the pain at the top of the head, sometimes the first symptoms.
2. Increased intracranial pressure due to slow tumor growth, late symptoms of increased intracranial pressure with obstructive hydrocephalus.
3. Multiple groups of cranial nerve damage symptoms are easily affected by the nerves of the oculomotor nerve, trigeminal nerve, face, auditory nerve and nerve, often manifested as: ptosis, hearing loss, facial numbness, trigeminal neuralgia and diplopia.
4. Cerebellar damage symptoms gait, ataxia and horizontal tremor of the eye.
5. The involvement of vertebral artery and basilar artery can manifest TIA attacks.
6. Individual manifestations of cavernous sinus syndrome and rock tip syndrome (post-ocular pain, nerve palsy).
Examine
Examination of meningioma of rock slope
The pressure of lumbar puncture was increased, and the protein of cerebrospinal fluid was increased to varying degrees.
1. The skull X-ray film can help to understand the degree of hyperplasia or damage of the skull.
2. CT examination of CT and MRI is the most effective means of diagnosing meningioma in this area. In the examination, the contrast injection scan should be performed. Otherwise, there may be misdiagnosis. The CT scan is mainly characterized by the slope of the rock bone or the leaf shape or Oval-shaped uniform high-density or slightly high-density space-occupying lesions, a small number of tumors mixed with low-density lesions of different sizes, can be uniformly strengthened after injection of contrast agent, and more often round, oval or irregular, tumor It is connected to the dura mater with a broad base. Localized bone hyperplasia or bone destruction may occur, sometimes manifested as obvious destruction of the tip of the rock. In addition, CT can also indicate the degree of mastoid gasification and the location of the bone labyrinth, which is conducive to guiding the operation.
3. MRI examination Most meningioma signals are similar to gray matter. Most of the T1 weighted images are equal signals, and a few are low signals. On T2-weighted images, they can be high, etc., low signal, Gd-DTPA injection. Most of the tumors are intensified. Most meningiomas are separated from adjacent brain tissues, especially the brainstem. In addition, MRI is superior to CT in showing the relationship between meningioma and adjacent blood vessels, which can be clearly displayed in three-dimensional manner. The location and size of the tumor, the direction of tumor invasion, the presence or absence of basilar artery and branch involvement, and more importantly, on the T2-weighted image, the presence of the arachnoid layer of the peritumoral can be observed, whether there is a brain dry membrane invasion, or not Brain stem edema, which is very important for the preoperative evaluation of the disease (Fig. 1). When the meningioma surrounds or squeezes the internal carotid artery and the basilar artery, the blood flow occurs due to the rapid flow of blood in the blood vessel. Both the T2 and the T2-weighted image are low signal regions.
4. Cerebral angiography Because the tumor blood supply is very rich, therefore, selective cerebral angiography before surgery is necessary for guiding surgery. Cerebral angiography can observe the blood supply of the tumor, so as to block the blood supply artery and cerebral angiography. The blood supply artery of the meninges in the upper sloping area mainly includes the meningeal pituitary trunk of the internal carotid artery, the middle meningeal artery, the basilar artery branch, the vertebral artery meningeal branch and the pharyngeal ascending artery slope branch, and can simultaneously observe the basilar artery shifting to the contralateral side. The superior cerebellar artery and the pharyngeal ascending artery are elongated (backward and contralaterally displaced), and sometimes pathological vascular staining may occur.
Diagnosis
Diagnosis and diagnosis of meningioma of rock slope
diagnosis
According to typical clinical manifestations and CT, MRI and other findings, meningioma in the rock-slope area is easily diagnosed.
Differential diagnosis
Meningioma in the slope area of the rock bone is sometimes confused with slope chordoma, chondrosarcoma, etc., should be noted.
1. Spine chordoma chordoma is derived from the chordate embryo remnant, mostly in the skull base or spine. The skull base chordoma is mostly located on the slope, accounting for 0.15% to 0.2% of the intracranial tumor. The tumor is mostly located outside the dura mater, but sometimes Invasive growth and breakthrough of the dura mater, mostly flat or spherical, mainly manifested as headache, limb weakness, language is unclear, cough, etc. If the tumor grows in different directions, the corresponding symptoms appear, from clinical manifestations It is difficult to distinguish from meningioma, but the calcification of the skull flat meningioma is rare, and more than half of the chordomas have spots or small calcifications, which are serious damage to the bone. CT shows that the tumor is irregularly slightly dense and the boundary is clear. There are many scattered points, flaky calcification, slope, and the saddle has extensive bone destruction. Occasionally, the tumor protrudes into the nasopharyngeal cavity, most of which does not appear to be enhanced. The MRI T1 image is low signal, and there are many spotted high signals, T2 Like a high signal with unevenness, it can have moderate contrast enhancement.
2. Cholesteatoma is mainly derived from ectodermal residual ectodermal tissue, which occurs in the cerebellopontine angle, saddle area, ventricle and rock bone slope area, accounting for 0.7% to 2% of intracranial tumors, more common in young adults. It often manifests as one side trigeminal neuralgia or hemifacial spasm, facial numbness, hearing loss, etc. Typical CT findings are clear irregular low-density shadows along the growth boundary of the cerebral pool, with no contrast enhancement or boundary ring enhancement of the injected contrast agent. MRI showed a low T1 weighted signal slightly higher than cerebrospinal fluid, T2 weighted higher than the high signal of cerebrospinal fluid, with internal spacing and no contrast enhancement.
3. There is no obvious clinical manifestation of schwannomas and meningiomas, but CT manifests as equal or low-density lesions, or cystic, which can be uniform or annular enhancement. Bone window observation can show the destruction of rock bone tip, around the tumor. No edema, can be dumbbell-shaped riding in the middle and posterior fossa growth, MRI T1 image shows a low signal, T2 image shows a high signal or mixed signal, there may be more obvious contrast enhancement, but weaker than meningioma.
4. The incidence of chondrosarcoma of chondrosarcoma is low, the age of onset is 40-50 years old, no obvious symptoms in the early stage, and the occurrence of cranial nerve palsy and intracranial pressure increases. CT examination has bone destruction, which is expressed as equal density or high density. There is calcification in the tumor, and the enhanced tumor is not enhanced or mildly enhanced. MRI shows long T1 and long T2 signals, and the tumor is mildly enhanced after injection of Gd-DTPA.
5. Others need to be differentiated from nasopharyngeal carcinoma and brain stem tumors that are invaded to the skull base.
