Meningiomas confined to the optic canal and foramina.

We present two cases, each with a small meningioma arising from the sheath of an optic nerve in the canal. Both cases demonstrate the paucity of clinical and radiographic signs occurring with these tumors. The diagnosis must be strongly suspected when a middle aged white woman slowly and progressively loses vision in one eye in the absence of remission or other neurological findings. We review similar cases reported in the literature that have been proven by biopsy.