[High-resolution computed tomography in primary and secondary lesions of the optic nerve sheath complex ].

High resolution CT was found to be an extremely useful and sensitive method for evaluation and diagnosis of lesions involving the optic nerve sheath complex. Segmental "tram tracking" associated with fusiform or focal eccentric nerve sheath enlargement was confirmed to be of neoplastic origin in all cases, whereas "tram tracking" and tubular nerve sheath thickening included tumorous and a great variety of non-tumorous lesions as well.