Arachnoid cysts involving a portion of the intraorbital optic nerve

Two patients were seen. One had chronic monocular choked disc, visual loss, and optociliary veins; the other had optic atrophy and a left-sided frontotemporal porencephalic cyst. Both patients were found on pathologic examination to have arachnoid cysts involving a localized segment of the intraorbital optic nerve.