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Mary Tyler Moore to Undergo Surgery for Meningioma

MedpageToday
Veteran actress Mary Tyler Moore will be undergoing surgery to remove a benign brain tumor called a meningioma. Moore's reprepsentative told magazine:
"At the recommendation of her neurologist, who has been monitoring this for years, and a neurosurgeon, Mary decided to proceed with this fairly routine procedure."
Moore, 73, is best known for her iconic roles as Laura Petrie on the Dick Van Dyke Show(1961–66), and Mary Richards on the Mary Tyler Moore Show (1970–77). She was also nominated for an Academy Award for her role in Ordinary People. Moore has written two memoirs. The first was After All, released in 1995, in which she acknowledged that she is an alcoholic. The next, Growing Up Again: Life, Loves, and Oh Yeah, Diabetes, was released on April 1, 2009, and focuses on living with .

Meningeal tumors form in the meninges, the system of membranes that envelop the central nervous system. Meningeal tumors are the most common type of all CNS tumors and can form from different types of brain or spinal cord cells. A meningioma is most common in adults between the ages of 40 and 70. According to the , this year, approximately 21,270 people in the United States will be diagnosed with a meningioma, and current estimates suggest more than 206,900 Americans are living with a meningioma or have been treated for a meningioma.

"Location, Location, Location..."
Meningiomas are frequently described by their location. Location is important in determining the symptoms that a particular tumor may cause, how soon symptoms may become apparent, and what the treatment options may be.
Falx and Parasagittal meningiomas

The falx is the groove that runs between the two sides of the brain (front to back), and contains a large blood vessel (superior sagittal sinus). Parasagittal tumors, which represents 25% of meningiomas,  lie near or close to the falx. Large parasagittal meningiomas may present with bilateral leg weakness. Removing a tumor in the falx or parasagittal region can be difficult because to the proximity of the tumor to the major blood vessels.

Convexity meningiomas

These grow on the surface of the brain, often toward the front. They may not produce symptoms until they become quite large. Symptoms of a convexity meningioma include seizures, focal neurological deficits, or headaches. They comprise 20% of meningiomas. People with tumors on the convexity tend to do better than those with tumors that are difficult to access.


Sphenoid meningiomas

Sphenoid meningiomas (20% of meningiomas) lie along the sphenoid ridge behind the eyes. These tumors can cause visual problems, loss of sensation in the face, or facial numbness. Tumors in this location can sometimes involve the blood sources of the brain (e.g. cavernous sinus, or carotid arteries), making them difficult or impossible to completely remove.


Olfactory groove meningiomas

Olfactory groove meningiomas grow along the nerves that run between the brain and the nose. Tumors growing here can cause a loss of smell, and if they grow large enough,they can also compress the optic nerve, causing visual symptoms. Meningiomas also grow on the optic nerve and can cause visual problems, including visual field loss or even blindness. Changes in the sense of smell and mental status changes can be subtle, so that these tumors can be fairly large at the time of diagnosis. Ten percent of meningiomas are olfactory groove tumors.


Posterior fossa meningiomas

Posterior fossa tumors lie on the underside of the brain. Accounting for approximately 10% of meningiomas, posterior fossa meningiomas can press on the cranial nerves, causing facial and hearing problems. Petrous meningiomas often press on the trigeminal nerve, causing a condition called trigeminal neuralgia.  Their location makes them much more difficult to reach surgically.

Intraventricular meningiomas

Intraventricular meningiomas are associated with the ventricular system. As such, they can block the flow of cerebrospinal fluid. The resultant increase in intracranial pressure can produce headaches and dizziness.

Intraorbital meningiomas

Intraorbital meningiomas grow around the eye sockets can cause an increase in intraocular pressure, giving the eyes a bulging appearance. They can also cause an increasing loss of vision.

Spinal meningiomas

Spinal meningiomas account for less than 10% of meningiomas. They tend to occur in women (with a female/ male ratio of 5:1), usually between the ages of 40 and 70. They are intradural (within or enclosed within the dura mater), extramedullary (outside or unrelated to any medulla) tumors occurring predominantly in the thoracic spine. They can cause back pain, or pain in the limbs from compression of the nerves where they run into the spinal cord.

Treatment for meningiomas

Where possible, surgery is the first form of treatment for meningioma and in many cases the tumor can be removed completely. Conventional radiotherapy may be used after surgery if the meningioma cannot be totally removed, in order to destroy any remaining tumor cells. Radiotherapy and radiosurgery have become a promising alternative to surgery in the treatment of surgically inaccessible meningiomas.

Small, asymptomatic (few or no symptoms or signs) meningiomas can be carefully observed and followed with regular MRI scans. According to the late , a neurosurgeon from Massachusetts General Hospital, the indications for observation include:
  • asymptomatic patients with little or no edema in the adjacent brain areas,
  • patients with mild or minimal symptoms or those with a long history, 
  • older patients with a seizure or very slowly progressing symptoms, patients in whom treatment carries a significant risk, 
  • patients who make the decision after being presented with the treatment options.