(or '''retrobulbar neuritis''') is the
Inflammation of the
Optic Nerve that may cause a complete or partial loss of vision.
The optic nerve comprises
Axon s that emerge from the
Retina of the
Eye and carry visual information to the primary visual nuclei, most of which is relayed to the
Occipital Cortex of the
Brain to be processed into vision.
Inflammation of the optic nerve causes loss of vision usually due to the swelling and destruction of the
Myelin sheath covering the optic nerve.
Direct axonal damage may also play a role in nerve destruction in many cases.
Some causes are viral-bacterial infections (e.g.
Herpes Zoster ),
Autoimmune Disorder s (e.g.
Lupus ) and the inflammation of vessels (
Vasculitis ) nourishing the optic nerve.
Optic neuritis can also emerge as an attendant, first, or sole manifestation of
Multiple Sclerosis .
Major symptoms are sudden loss of vision (partial or complete) and occasionally pain on movement of the eyes. Most patients with optic neuritis may lose their color vision, as well.
On medical examination the head of the optic nerve can easily be visualised by an
Ophthalmoscope . In many cases, only one eye is affected and patients may not be aware of the
Loss Of Color Vision until the doctor asks them to close or cover the healthy eye.
In most cases, visual functions return to near normal within 8 to 10 weeks, but they may also advance to a complete and permanent state of visual loss.
Therefore, systemic intravenous treatment with
Corticosteroid s, which may quicken the healing of the optic nerve, prevent complete loss of vision, and delay the onset of other multiple sclerosis symptoms, is often recommended. It has been demonstrated that oral administration of corticosteroids in this situation may lead to more recurrent attacks than in non-treated patients (though oral steroids are generally prescribed after the intravenous course, to wean the patient off the medication). This effect of corticosteroids seems to be limited to optic neuritis and has not been observed in other diseases treated with corticosteroids.
Very occasionally, if there is concomittant increased
Intracranial Pressure the sheath around the optic nerve may be cut to decrease the pressure.
When optic neuritis is associated with MRI lesions suggestive of multiple scelrosis (MS) then general
Immunosuppressive therapy for MS is most often prescribed.
Optic neuritis is often diagnosed by the
Neurologist and managed by an
Ophthalmologist . However, ideally, a
Neuro-ophthalmologist should be consulted at a major university hospital center.
