Deep Sylvian Meningioma without Dural Attachment – A Case Report

Deep Sylvian meningiomas are rare, accounting for 0.3–0.4% of all meningiomas, and mostly present in young adults and children. We report on a 32-year-old man who presented with headache but had no neurological deficits. Computed tomography of brain revealed a 24 × 19 × 21 mm(3) mass lesion in the right Sylvian fissure with calcification. Magnetic resonance imaging showed that the lesion was isointense on T(1)- and T(2)-weighted images (WI), with homogenous enhancement on post-gadolinium T(1)WI. The lesion was surgically removed via right fronto-temporal craniotomy. The tumor was located in deep Sylvian fissure and had no dural attachment. Histopathological examination of the lesion revealed both meningothelial and fibroblastic features, thereby suggesting the diagnosis of transitional meningioma (WHO grade I), with Ki-67 labeling index of 6.9%. Thus, meningioma should be considered as a differential diagnosis of enhancing mass lesions in the Sylvian fissure even in the absence of dural tail sign, especially in young adults and children.