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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). 2 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). |