الفهرس 
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Abstract
The term meningioma was introduced by Cushing in 1922
to replace the previous term dural endothelioma.
Meningiomas are the second most common intra-cranial
tumors, they come after gliomas, and constitute about 13-18
percent of primary brain tumors. If supratentorial tumors only
are considered, meningiomas constitute above 20 percent
(Taveras and Wood, 1976).
Meningiomas commonly occur in either middle or old
age, rarely in childhood, there is a significant female
preponderance of these tumors (Rohringer eta!., 1989).
The great majority of meningiomas are benign tumors.
However, malignant changes can occur in all types of ordinary
meningiomas (Kitahara et al., 1985). Although the line of
demarcation between benign and malignant meningioma is
equivocal (Kornblith, 1978) the World Health Organization
(WHO) considered six histopathological Criteria to define
malignant meningioma and these include, hypercellularity,
loss of architecture, nuclear pleomorphism, mitotic index, focal
necrosis and brain invasion (Rohringer et al., 1989).
Extracranial metastasis of meningiomas to distant sites via
the blood stream or C.S.F. are extremely rare and are said to
arise in less than one in 1000 meningioma cases (Fukushima et
a!., 1989).
The clinical presentation of meningioma depends
primarily on the location of the tumor and its growth rate,
however seizures occur in 50 percent of patients with
meningioma (Symon, 1982).
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Introduction & Aim of the Work
The neuroradiologic study of meningiomas are often
gratifying both for the abundance of striking radiologic signs
these lesions produce and because of their surgical cure. Plain
X-ray films, C.T. scan will be often used preoperatively
(Rosenberg, 1984). However, MRI is more diagnostic especially
in tumor recurrence (Zimmerman et al., 1985).
Simpson 1957 found that complete excision of a
meningioma with its dural attachment is followed by fewer
clinical recurrences.
The primary concern in the post-operative period is that a
hematoma or brain edema but postoperative seizures, frontal
manifestation, subdural hygroma, infection, C.S.F. fistula,
visual impairment, motor power affection, cranial nerves
affection or recurrence may occur after surgical management of
intracranial meningiomas (Maxwell and Chou, 1988).