Neuroimmunology Program - IDIBAPS

What is Optic Neuritis?

Acute Optic Neuritis (AON) is a rare condition that affects to young people and can produce impaired vision that limits the quality of life in young people.


AON is a disease that appears over the 25-35 years and that caused, ocular pain, blurred vision, bad discrimination of colours and limited vision in some part of the visual field. It begins during few days and after some weeks of maximum visual impairment, vision starts to recover. Recovery is often uncompleted since patients usually complaint about difficulties for reading under low contrast situations (gray over white) as well as for discriminating some colours.


In the AON, inflammation attacks optic nerve integrity. Inflammation may be produced due to several causes including infections and more frequently, a global inflammatory process of the central nervous system (CNS) such as multiple sclerosis (MS) or neuromyelitis optica spectrum disorders (NMOSD). If the cause of the inflammation it is not identified, physicians describe this as idiopathic AON.


We have not specific treatment for AON. Intravenous corticoids administration shortens symptomatic period of AON but there are no evidences in favor of a better recovery to the nerve for those receiving corticoids than for patients not receiving any therapy. MS-related AON patients should be re-evaluated in order to define a strategy to avoid future relapses of MS. There is an important ongoing research activity working to develop new therapies for neuron protection. In that line, Anti-LINGO trial in which we participate found that optic nerve of patients treated with anti-LINGO improved its velocity conduction as to compared to untreated patients. Bionure is doing important research in order to develop a neuroprotective drug (BN201)


Typical clinical phenotype of AON drives the diagnosis of AON. However, there are important ancillary test to support the diagnosis and to evaluate the ultimate cause of inflammation of the optic nerve. The most important is the optical coherence tomography (OCT) that can evaluate the inflammation of the optic nerve and monitories the progression of the damage. Other tools that may be useful to confirm MS diagnostic are:

  • Functional visual proves as campimetry, colour vision and high and particularly low-contrast visual acuity whose impairment is characteristic of this entity.
  • Cerebral magnetic resonance that permits to identify inflammation of the optic nerve and presence / absence of typical lesions of MS. Visual evoked potentials (pattern and multifocal) that allow for identification of mild cases informs about the recovery.