Meningiomas are the set of tumors that arise contiguously to the meninges.
Meningiomas may occur intracranially or within the spinal canal. Meningiomas are commonly found at the surface of the brain, either over the convexity or at the skull base. In rare cases, meningiomas occur in an intraventricular or intraosseous location

Pathophysiology

They are thought to arise from arachnoidal cap cells, which reside in the arachnoid layer covering the surface of the brain.

Frequency

Symptomatic meningiomas are approximately 2 cases per 100,000 individuals. Meningiomas account for approximately 20% of all primary intracranial neoplasms. However, Meningiomas are multiple in 5-40% of cases, particularly when they associated with neurofibromatosis type 2 (NF2). Familial meningiomas are rare unless associated with NF2.

Mortality/Morbidity
Fortunately CT or MRI identifies some meningiomas which can assess unrelated diseases or conditions. Therefore, some patients die with meningioma and not from it. Estimates of the 5-year survival usually range from 73-94%.

Most meningiomas 2.5 cm or less in diameter do not proceed to cause symptoms in the 5 years following their discovery.

Meningiomas usually grow slowly, and they may produce severe morbidity before causing death.

Sex
Meningiomas afflict women more often than men.
Meningiomas are equally distributed between boys and girls.

Age •The incidence increases with age.

The following are some of the symptoms of Meningioma:

•Irritation: By irritating the underlying cortex, meningiomas can cause seizures.New-onset seizures in adults justify neuroimaging (eg, MRI) to exclude the possibility of an intracranial neoplasm.
• Compression: Localized or nonspecific headaches are common. Compression of the underlying brain can give rise to focal or more generalized cerebral
dysfunction, as evinced by focal weakness, dysphasia, apathy, and/or somnolence.
• Stereotypic symptoms: Meningiomas in specific locations may give rise to the stereotyped symptoms listed in the Table.• Vascular: This presentation, although rare, should be considered. Meningiomas of the skull base may narrow and even occlude important cerebral arteries, possibly presenting either as transient ischemic attack (TIA)–like episodes or as stroke.
• Miscellaneous
o Intraventricular meningiomas may present with obstructive hydrocephalus.
o Meningiomas in the vicinity of the sella turcica may produce panhypopituitarism.
o Meningiomas that compress the visual pathways produce various visual field defects, depending on their location.
o Rarely, chordoid meningiomas can present with hematologic disturbances, namely Castleman syndrome.

Physical

• papilledema, decreased mentation and, ultimately, to brain herniation.
• anosmia, visual field defects, optic atrophy, diplopia, decreased facial sensation, facial paresis, decreased hearing, deviation of the uvula, and hemiatrophy of the tongue.
• pyramidal signs that are exemplified by pronator drift, hyperreflexia, positive Hoffman sign, and presence of the Babinski sign.
o Compression of the dominant (usually left) parietal lobe - agraphia, acalculia, right-left disorientation, and finger agnosia.
o Compression of the nondominant (usually right) parietal lobe - tactile and visual extinction and neglect of the contralateral side.
o Compression of the occipital lobes - congruent homonymous hemianopsia.
• Spinal meningiomas - Brown-Sequard syndrome (ie, contralateral decreased pain sensation, ipsilateral weakness, decrease in position sense), sphincteric weakness and, ultimately, complete quadriparesis or paraparesis.

Causes

• Trauma and viruses have been investigated as possible causative agents for development of meningiomas
• The role of inflammation (eg, posttraumatic)
• radiation
• Genetic causes
• Hormones: causing increased incidence in women versus

Treatment management would be precisely on the basis of underlying cause. The bigger meningiomas usually require surgical intervention.