Clinoidal meningioma arising from falciforme process of optic canal: case report and review

A 56-year-old female with an initial symptom of unilateral progressive visual disturbance presented with a clinoidal meningioma arising from a falciforme process of the optic canal. Magnetic resonance images with gadolinium-diethylenetriaminepenta-acetic acid demonstrated marked enhancement of a small mass, approximately 1 cm in diameter, roofing the right optic nerve at the intracranial opening of the optic canal. The clinoidal meningioma is rarely reported and the precise originating location of the neoplasm has not been clarified. This is the first case of clinoidal meningioma, which is confirmed by the operative observation as the origin of the neoplasm is a falciforme process of the optic canal. Magnetic resonance images with enhancement are useful for the diagnosis of such a small neoplastic lesion adjacent to bone structure and total removal without a deterioration of visual function is achieved by careful microsurgical procedure.