[Misinterpretation of unilateral swelling of the optic nerve].

The problems of differential diagnosis in the interpretations of orbital CT results are illustrated by three cases of unilateral swelling of the optic nerve. The apparently similar changes in a nonspecific perineural inflammation and two cases of an endotheliomatose meningioma are described. The importance of the clinical picture and of CT examination for diagnostic classification is illustrated by these examples.