Deep Sylvian Meningioma: A Case Report and Review of the Literature

Abstract Introduction Meningiomas are extra-axial tumors. They usually display a dural attachment, although meningiomas without dural attachment are extremely rare and reported only occasionally in the literature. In this article, the authors present a new case of a deep sylvian meningioma and briefly review the relevant literature. Case Report We present the case of a 39-year-old man presented with 1- month history of headache associated with an episode of generalized tonic–clonic seizure. Neurological examination showed no abnormality. Magnetic resonance imaging (MRI) demonstrated a lesion located in the right temporo-frontal region which was isointense on T1 and hypointense on T2 with homogeneous enhancement after gadolinium administration. Coronal, axial, and sagittal MRI revealed no dural attachment and the mass appeared to be completely surrounded by brain parenchyma. Intraoperatively, the lesion was presented as a subcortical mass and was mainly in the posterior part of right sylvian fissure. The histological diagnosis showed a World Health Organization grade I meningioma, transitional type. Conclusion Deep sylvian meningiomas are a rare entity. Preoperative diagnosis is difficult. Nevertheless, neurosurgeons and neuropathologists should be aware of this possibility and should include this hypothesis in the differential diagnosis of an intraparenchymal tumor.