Optic neuritis includes inflammatory and demyelinating disorders of the optic nerve like papillitis (inflammation of the optic disc), retrobulbar neuritis (inflammation of retro-ocular portion of optic nerve) and neuroretinitis (when both optic nerve and retina are inflamed). Etiology may be hereditary, systemic bacterial/viral infections, endophthalmitis, orbital cellulitis, demyelinating disorders or idiopathic in nature.

Clinical features:

Ø  Sudden, progressive and profound visual loss is the hallmark of acute optic neuritis.

Ø  Decreased dark adaptation and impairment of colour vision, visual obscuration in bright light and episodic obscuration on physical exertion, hot bath, fatigue etc.

Ø  Depth perception, particularly for the moving object may be impaired (Pulfrich’s phenomenon). Patient may complain of mild dull eye ache. It is more marked in patients with

Ø  retrobulbar neuritis than with papillitis. Pain is usually aggravated by ocular movements, especially in upward or downward directions due to attachment of some fibers of superior rectus to the dura mater.

Ø  Marked abnormality in papillary responses to light reflex (sluggish or afferent pupil defect).

Ø  Fundus examination reveals hyperaemia of the disc and blurring of the margins. Disc becomes oedematous and physiological cup is obliterated. Retinal veins are congested and

Ø  tortuous. Splinter haemorrhages and fine exudates may be seen on the disc.

Ø  Slit-lamp examination may reveal inflammatory cells in the vitreous. The most common field defect in optic neuritis is a relative central or centrocaecal scotoma.

Pharmacological treatment:

1.       Efforts should be made to find out and treat the underlying cause. There is no effective treatment for idiopathic and hereditary optic neuritis and that associated with demyelinating disorders.

2.       Corticosteroid therapy may shorten the period of visual loss, but will not influence the ultimate level of visual recovery in patients with optic neuritis.

Oral prednisolone therapy alone is contraindicated in the treatment of acute optic neuritis, since, it did not improve visual outcome and was associated with a significant increase in the risk of new attacks of optic neuritis.

l  Indications for intravenous methylprednisolone in acute optic neuritis patients with a normal brain MRI scan are:

i.      Visual loss in both eyes simultaneously or subsequently within hours or days of each other.

ii.    When the only good eye is affected.

iii. When the slow progressive visual loss continues to occur.

3.       Inj. methylprednisolone 1gm/day (or 15 mg/kg/day) intravenously in 2-4 divided doses for 3 days followed by Tab. prednisolone 1 mg/kg/day orally for 11 days tapered over the next week.

Patient education:

u  Explain the recurrent nature of the disease and that permanent vision loss can occur.

u  Avoid factors provoking transient visual obsurations like physical exertion, hot weather, stress, anger etc