Researchers discover progressive brain damage after optic neuritis attacks

Researchers have made significant progress towards understanding and treating MS after discovering progressive brain damage after attacks of optic neuritis.

Optic neuritis is a symptom of MS which causes the nerves carrying information between the eye to the brain to become inflamed and damaged. It is often the first symptom of the disease.

A full understanding of the way neurodegeneration occurs in MS remains vague. The researchers, led by Dr Ahmed Toosy and Dr Carmen Tur, studied the optic nerve and found patients with optic neuritis had progressive damage in key nerve bundles in the brain that carry information from the eyes to the visual cortex, called optic radiations.

This type of damage to the brain is known as transsynaptic degeneration because it occurs beyond the synapses – junctions between nerve cells that allow information to flow in the nervous system. 

Researchers also discovered patients with optic neuritis who had smaller optic nerves after three months of an optic neuritis attack had greater damage, consistent with transsynaptic degeneration.

BRC-supported Dr Tur, from UCL’s Institute of Neurology, said: “Although previous research has revealed transsynaptic degeneration, we have for the first time characterised its evolution over time after a first episode of optic neuritis. We discovered that once the optic nerve is damaged there is remote damage in the brain, this occurs because degeneration goes beyond the synapses to the optic radiations.”

The discovery of these mechanisms of tissue damage at a microscopic level bring researchers one step closer to establishing neuroprotective drugs for people with MS – currently there are none.

To read Longitudinal evidence for anterograde trans-synaptic degeneration after optic neuritis visit the Brain website.