[Technics for exploring the optic nerve]

This issue propose an inventory of the methods of investigation which help for the diagnosis of the optic neuropathies. These investigation methods are shortly presented, and the situation in which there are usefull are presented. Some of these investigation are expensive and are not available in any ophthalmological hospitals. Despite of the great number of investigations, the problem of the etiopathogenesis of the optic neuropathies is not completely elucidated.