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

(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

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]
References in periodicals archive ?
Clinicopathologic findings in a dog with a retrobulbar meningioma. Journal of Veterinary Diagnostic Investigation, v.23, n.857-862, 2011.
In the current study, meningiomas particularly benign were found more frequent in females but malignant meningioma were more commonly observed in male, which is corroborating the reports from Samadi N et al.18 and Kane AJ et al.16 The benign meningioma showed variable appearance like hypointense, isointense and slightly hyperintense on DWI and ADC maps with ADC values of more than 0.85x10-3mm2/sec while malignant/atypical meningiomas returned hyperintense signals on DWI and hypointense in ADC maps, with ADC values less than 0.85x10-3mm2/sec.
It has been proposed that brain edema in meningiomas is associated with many factors including the size, location, and histological features of the tumor; the secretory activity of meningioma cells, meningioma with positive sex hormone receptors, venous channel compression, and occlusion by the tumor.
The most common CNS tumour in this study is Meningioma followed by Astrocytoma.
Successful inhibition of meningioma cell growth was achieved in-vitro with somatostatin use and was reported more than 30 years ago.6 In order to learn its efficacy in human subjects Johnson and his colleagues conducted a phase II randomized controlled trial to study the efficacy of subcutaneous octreotide (somatostatin analogue) in recurrent meningioma and haemangiopericytoma.
One case of spinal astrocytoma was diagnosed as ependymoma on crush cytology, while one case each of cerebellopontine angle schwannoma and cerebellar hemangioblastoma were misinterpreted as meningioma and benign mesenchymal tumor, respectively [Table 3].
The positive result of GM1 antibody prompted the GBS ganglioside-related AMAN, positive IgM and IgG was considered the application of ganglioside and blood-brain barrier may be damaged after meningioma surgery which eased the drug enter the CSF circulation and induced lesions.
Primary extracranial meningioma presenting as a cheek mass.
Somatostatin receptor 2a is a more sensitive diagnostic marker of meningioma than epithelial membrane antigen.
Meningioma, WHO grade I, with intracranial, intraosseous and extracranial components
This radiologic triad is highly suggestive of an intracranial meningioma extending to the middle ear and mastoid; this was confirmed by additional magnetic resonance imaging (MRI) demonstrating a right temporal en plaque meningioma spreading to the adjacent sphenoid wing (Figure 2).
In case of meningiomas choline was 0.5 in high grade and 0.4 for low grade while NAA was depressed to 0.2 for both grades.