meningioma

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meningioma

 [mĕ-nin″je-o´mah]
a hard, usually vascular tumor occurring mainly along the meningeal vessels and superior longitudinal sinus, invading the dura and skull and leading to erosion and thinning of the skull.
angioblastic meningioma angioblastoma (def. 2).

me·nin·gi·o·ma

(mĕ-nin'jē-ō'mă),
A benign, encapsulated neoplasm of arachnoidal origin, occurring most frequently in adults; most common form consists of elongated, fusiform cells in whorls and pseudolobules with psammoma bodies frequently present; meningiomas tend to occur along the superior sagittal sinus, along the sphenoid ridge, or in the vicinity of the optic chiasm; in addition to meningothelial meningioma, fibrous, transitional, metaplastic, psammomatous, secretory, clear cell, papillary, rhabdoid, chordoid, lymphoplasmocytic, angiomatous, microcystic, rhabdoid, atypical, and anaplastic varieties are recognized.
[mening- + G. -oma, tumor]

meningioma

/me·nin·gi·o·ma/ (mĕ-nin″je-o´mah) a benign, slow-growing tumor of the meninges, usually next to the dura mater, which may invade the skull or cause hyperostosis, and often causes increased intracranial pressure; it is usually subclassified on the basis of anatomic location.
angioblastic meningioma  one containing many blood vessels of various sizes.
convexity meningiomas  a diverse group of meningiomas located within the sulci of the brain, usually anterior to the rolandic fissure.
psammomatous meningioma  one containing many psammoma bodies.

meningioma

(mə-nĭn′jē-ō′mə)
n. pl. meningio·mas or meningio·mata (-mə-tə)
A slow-growing tumor of the meninges, occurring most often in adults.

meningioma

[minin′jē·ō′mə] pl. meningiomas, meningiomata
Etymology: Gk, meninx, membrane, oma, tumor
a mesenchymal fibroblastic tumor of the membranes enveloping the brain and spinal cord. Meningiomas grow slowly, are usually vascular, and occur most commonly near the superior longitudinal transverse and cavernous sinuses of the dura mater of the brain. The tumors may be nodular, plaquelike, or diffuse lesions that invade the skull, causing bone erosion and compression of brain tissue. Meningiomas usually occur in adults.
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Meningioma

meningioma

A tumour of meninges and meningeal cells, which is most common in middle-aged women and may occur in a background of neurofibromatosis type 2. Aggressive meningiomas are characterised by bone destruction, florid mitotic activity and metastases.
 
Clinical findings
Often asymptomatic, slow-growing masses attached to the dura, usually where arachnoid villi are prominent. The symptoms are related to tumour growth and compression. 

Prognosis
5-year survival, 70%.

Types
Grade 1—Benign/typical
• Angiomatous
• Fibrous (fibroblastic)
• Lymphoplasmacyte-rich
• Meningiothelial
• Metaplastic
• Microcystic
• Psammomatous
• Secretory
• Transitional (mixed)

Grade 2—Atypical
• Chordoid
• Clear cell
• Oncocytic

Grade 3—Malignant/anaplastic
• Anaplastic
• Papillary
• Rhabdoid

meningioma

Neurosurgery A tumor of meninges and meningeal cells, most common in middle-aged ♀ Clinical Often asymptomatic, usually slow-growing masses, attached to dura, usually where arachnoid villi are prominent; Sx are related to tumor growth and compression Prognosis 5-yr survival 70%. See Malignant meningioma.

me·nin·gi·o·ma

(mĕ-nin'jē-ō'mă)
A benign, encapsulated neoplasm of arachnoidal origin, occurring most frequently in adults; most frequent form consists of elongated, fusiform cells in whorls and pseudolobules with psammoma bodies frequently present; meningiomas tend to occur along the superior sagittal sinus, along the sphenoid ridge, or in the vicinity of the optic chiasm; in addition to meningothelial meningioma, angiomatous, chondromatous, osteomatous, lipomatous, melanotic, fibroblastic and transitional varieties are recognized.
[mening- + G. -oma, tumor]

meningioma

A tumour of the cells of the MENINGES. Most meningiomas are fixed to the DURA MATER and are benign but, because of their location and the bony surroundings of the nervous system, may do serious damage by compression of neurological structures. Treatment is by surgical removal and this is often successful.

me·nin·gi·o·ma

(mĕ-nin'jē-ō'mă)
A benign, encapsulated neoplasm of arachnoidal origin, occurring most frequently in adults; tends to occur along the superior sagittal sinus, along the sphenoid ridge, or in the vicinity of the optic chiasm.
[mening- + G. -oma, tumor]

meningioma

(mənin´jēō´mə),
n a mesenchymal fibroblastic tumor of the membranes enveloping the brain and spinal cord. They grow slowly, are usually vascular, and occur most commonly near the superior longitudinal, transverse, and cavernous sinuses of the dura mater of the brain.

meningioma

a common, well-defined, firm intracranial neoplasm of animals arising from leptomeningeal cells, which occurs in basal locations, over the cerebral, cerebellar convexities, and in the spinal cord. One subtype is characterized by psammoma bodies (central calcified material).

angioblastic meningioma
angioblastoma.
epithelioid meningioma
see meningotheliomatous meningioma (below).
meningotheliomatous meningioma
a diffusely cellular mesodermal tumor with cells in sheets or in pseudoalveoli.