Optic nerve: a concise review of the anatomy, pathophysiology and principal acquired disorders.

The Authors review the acquired diseases of the optic nerve (o.n.) through a selection of a few main nosological categories elaborated according to recent literature and neuro-imaging developments. The proposed selection does not coincide with a classification as it includes different topics, some listed according to their aetiology, others on the clinical presentation. However, from a practical point of view, a simplified nosology should help in dealing with the complex variety of o.n. diseases and in tackling the difficulties of their differential diagnosis.