Meningioma

Meningioma

Prepared by : Abbas Abbas

Supervised by: Dr. Jawwad Zyadah

Definition

A meningioma is a tumor that arises from a layer of tissue that covers the brain and spine

arise from the arachnoid "cap" cells of the arachnoid villi in the meninges

Usually benign

Causes Most are sporadic, some familial

More common in women Radiation increase risk of developing meningioma

Trauma and viruses. However, no definitive proof has yet been found

The role of inflammation (eg, posttraumatic insult) resulting in the upregulation of COX-2

Cell phone use increases the risk of meningiomas

Genetic causes : 1 -NF2 gene

2 -Loss of chromosome 10

3 -Monosomy of chromosome 7

4 -smo gene

5 -Gorlin and Rubinstein-Taybi syndromes

Symptoms oAsymptomatic

Meningiomas produce their symptoms by several mechanisms :

1 -Irritation: seizures 2 -Compression: Localized or nonspecific headaches

are common, focal weakness, dysphasia3 -Vascular

4 -skull my be invaded and present as bulging mass

Stereotypic symptoms

MiscellaneousoIntraventricular meningiomas may present with

obstructive hydrocephalusoMeningiomas in the vicinity of the sella turcica may

produce panhypopituitarismoMeningiomas that compress the visual pathways

produce various visual field defects, depending on their location.

oRarely, chordoid meningiomas can present with hematologic disturbances, namely Castleman syndrome

Locations Parasagittal/falcine (25%)

Convexity (surface of the brain) (19%)

Sphenoid ridge (17%)

Suprasellar (9%)

Posterior fossa (8%)

Olfactory groove (8%)

Middle fossa 4%

Tentorial (3%)

Peri-torcular (3%)

Workup

Laparotomy studies : No specific laboratory tests are used to screen for meningioma.

Imaging study :oCT scan

oMRI oAngiography

oPET

Workup

HistologyoGrade 1 - Benign: These very slow-growing tumors oGrade 2 - Atypical: Usually slow-growing but can recuroGrade 3 - Anaplastic: More malignant, faster-growing

Treatment

Observation: Meningiomas are often slow growing, increasing is size only 1-2 mm per year .

oPatients with small tumors and mild or minimal symptoms, no impact on quality of life, and little or no swelling in adjacent brain areas.

oOlder patients with very slowly progressing symptoms. Related seizures can be controlled with medication.

Treatment

Medical care It is restricted either to perioperative drugs or to medications that

are used after all other means of treatment have failedocorticosteroids

oAntiepileptic ochemotherapy oRadiotherapy

oStereotactic radiosurgery

Treatment Surgical care :The constant principles in meningioma resection are the following :

oIf possible, all involved or hyperostotic bone should be removedoThe dura involved by the tumor as well as a dural rim that is free from

tumor should be resectedo Dural tails that are apparent on MRI are best removed, even though

some may not be involved with the tumoroMake a provision for harvesting a suitable dural substitute

(pericranium or fascia lata). The surgeon also can use commercially available dural substitutes

oIf feasible, always start by coagulating the arterial feeders to the meningioma

TreatmentMinimally invasive surgical options

Endoscopic removal of meningiomas through the noseoolfactory groove meningiomasotuberculum sella meningiomas

osellar meningiomas

Keyhole microsurgical removal using eyebrow incisionoolfactory groove meningiomasosphenoid wing meningiomas

Endoport removalointraventricular meningiomas

Yalow line; closed by occupationRed line ; alternative way

لكم شكرا