Optic neuritis

For a lay person:

Optic neuritis is inflammation of the optic nerve, usually causing blurred or dim vision in one eye with pain on moving the eye, developing over a few days. It is most common in young adults, especially women, and is often linked with multiple sclerosis; many people recover much of their vision over weeks to months.

For a trained medical person:

Typically a demyelinating optic neuropathy associated with multiple sclerosis, with other causes including neuromyelitis optica (AQP4), MOG antibody disease, infection and systemic inflammation. Diagnosis is clinical (reduced acuity, colour desaturation, relative afferent pupillary defect) with MRI of brain and orbits and antibody testing. High-dose intravenous corticosteroids may speed recovery, and atypical cases need urgent neurology and specialist management.

In Chinese medicine:

Liu and Tseng's textbook differentiates this condition into these patterns: Stagnant Heat at Liver Channel; Heat Condition Damaging Yin; Qi and Blood Deficiency; Liver and Kidney Deficiency; Wind-Heat at Lung and Heart; Excess Heat at Spleen and Stomach; Yin Deficiency with Deficient Fire. Treatment follows the pattern a patient presents with, not the Western diagnosis alone.

When to get help: Sudden vision loss or painful vision change needs same-day eye or emergency assessment. Optic neuritis needs specialist medical treatment and investigation for multiple sclerosis and related conditions; Chinese medicine is adjunctive at most.