Optic nerve/sheath enlargement. A differential approach based on high-resolution CT morphology.

Abstract
A wide variety of neoplastic and nonneoplastic processes can cause the intraorbital optic nerve and sheath to be enlarged on CT [computed tomography]. A large number of high-resolution CT scans were reviewed and enlargement was divided into 3 groups: tubular, fusiform and excrescent. Further subdivision was possible by determining whether distinct optic nerve lucency was present or absent.