Overview
As the name implies, meningiomas are tumors that originate in the meninges, which are membrane-like structures on the surface of the brain, like a layer of clothing on the surface of the brain, located underneath the skull and outside of the brain tissue. Most meningiomas are benign tumors that grow slowly and are less likely to recur after total removal. They are more common in women.
There are also membranous structures on the outside of the spinal cord that are connected to the meninges on the outside of the brain tissue, called the spinal meninges. Therefore, a spinal meningioma is the same in nature as a meningioma, except that it is called a spinal meningioma because it is located outside of the spinal cord.
Etiology:
The exact cause of the disease is not known, so there is no special prevention, no special contraindications, etc.
Clinical manifestations
The clinical symptoms of meningioma are complex and vary depending on the location of the growth and the corresponding brain tissue or nerves, so the diagnosis of meningioma cannot be based on symptoms. Common manifestations include chronic headache, dizziness, limb twitching, blurred vision, tinnitus, limb numbness, limb weakness, etc.
Diagnosis
The best test is cranial MRI plain + enhancement.
A portion of meningiomas are not easily detected by either cranial CT or cranial MRI plain examination only. Therefore, for patients with brain-related symptoms that do not resolve or even worsen over a long period of time, even if they have undergone cranial CT and cranial MRI plain examination and the examination report is normal, they must undergo cranial MRI enhanced examination to prevent missing the diagnosis.
In clinical practice, we often encounter patients with meningioma who have chronic headache and gradual blurring of vision, but the tumor was not detected early because only cranial CT or cranial MRI scan was done in the early stage. As a result, the diagnosis is delayed due to the failure to do MRI-enhanced examination.
Treatment.
Surgical resection: for the most radical approach.
Most meningiomas can be completely resected, such as meningiomas on the convex side of the brain.
A few meningiomas grow in special areas and are closely related to important neurovascular vessels, making total resection difficult, but most of them can be removed to relieve symptoms and prolong life. For example, meningioma in the oblique part of the brain and meningioma in the cavernous sinus area.
Radiation therapy (radiotherapy)
It is mainly applied to the following 3 cases
Post-operative residual tumors: As mentioned above, some tumors in special locations are closely related to important neurovascular and cannot be completely resected. Post-operative residual tumors need radiotherapy treatment, which can slow down or control the growth rate of tumors.
Those with deep location, difficult to resect with high surgical risk, and tumor with increasing trend
Post-operative pathology report shows meningioma with WHO grade 2-3
Regular review of films: For young patients with asymptomatic or mild symptoms found by chance, with deep location and difficult to remove due to high risk of surgery, they can be temporarily left untreated, and those with tumor tendency to increase in size can be treated with surgery and postoperative radiotherapy.
Do not do any treatment: For elderly patients with no symptoms or mild symptoms found by chance, due to the slow growth of tumor, no treatment can be done.
Post-operative follow-up
Start with 3-6 months review of cranial MRI plain + enhancement, and then gradually extend the interval every 1-2 years.
Surgical difficulty and risk issues:It mainly depends on the location of tumor growth and whether it encircles important vascular nerves.
Convex meningioma: surgery is relatively easy, easy to remove completely, not easy to recur, and usually does not leave sequelae.
Parasagittal sinus meningioma: more difficult, if it does not invade the sagittal sinus (the main cerebral reflux vessel), it can be easily removed. If it invades the sagittal sinus, it is not easy to remove completely, and postoperative hemiparesis occurs in some people, but most people can get better. (See article in my website: Surgery for paraganglioma of the sagittal sinus)
Meningioma of the anterior skull base: higher risk, postoperative cerebral edema, hemorrhage, and loss or loss of sense of smell. (See article in my website: Microdissection of anterior skull base meningioma – resection without traction technique)
Rock slope and ventral brainstem meningioma: the highest risk and most difficult surgery, not easy to complete because of the close relationship with large blood vessels and important cranial nerves. Postoperative complications such as facial palsy, double vision, and hearing loss are likely to occur. (See the article in my website: Brainstem ventral meningioma (craniocervical junction area) resection surgery)
Common tumor locations are shown in the following figure.
Below is a before and after comparison of typical sites of meningioma operated by me
Anterior approach to the sigmoid sinus for total resection of a meningioma of the rocky slope (58-year-old female)