Optic neuritis is a demyelinating inflammation of the optic nerve. It is also known as optic papillitis (when the head of the optic nerve is involved) and retrobulbar neuritis (when the posterior part of the nerve is involved). It is most often associated with multiple sclerosis, and it may lead to complete or partial loss of vision in one or both eyes.
Partial, transient vision loss (lasting less than one hour) can be an indication of early onset multiple sclerosis. Other possible diagnoses include: diabetes mellitus, low phosphorus levels, or hyperkalaemia.
Chronic alcohol abuse may produce problems in the optic nerve, called alcoholic optic neuritis. The main causes are vitamin B1 deficiency, and in some cases, zinc deficiency or raised lead levels.