Primary extradural meningiomas in head: a report of 19 cases and review of literature.

Primary extradural meningiomas (PEMs) in head were rare tumors. Here we analyzed 231 cases of PEMs in head (including our 19 cases) reported in the literature during the CT era. We found that PEMs in head accounted for 0.8%-1.8% of all meningiomas. The constituent ratio of male PEMs in head increases markedly. PEMs in head have bimodal distribution of ages. The most common presenting symptom was a mass in the region of the lesion. The average duration of symptom was 2.38 years. The skull convexities, paranasal sinuse and nasal cavity, and middle ear ranked as the top three of all sites of tumors. The most common type was Type II (calvarial or diploic). Among 231 cases, total, subtotal and partial removals of tumors were achieved in 89%, 5.5% and 3.1% respectively, and no death occurred perioperatively in all patients. 90% were benign, 5.6% atypical and 3.9% malignant in the 231 cases. The most common histopathological subtype was meningothelial meningioma. The recurrence and tumor-related death rates were 22.4% and 8.2% respectively during a mean 3.03-year follow-up. Our results demonstrate that PEMs in head have some marked clinical characteristics compared with primary intradural meningiomas. Total tumor removal together with a wide excision of all involved tissues followed by the reconstruction of tissue defects is the best surgical project. The prognoses are good in the benign cases after complete surgical resections.