Which investigations should be performed to confirm a diagnosis of optic neuritis and rule out other conditions?

Investigations to confirm optic neuritis and exclude other conditions include:

• Clinical assessment: Detailed history and neurological examination to identify typical features such as painful vision loss and to exclude other neurological causes ⁶.
• Magnetic Resonance Imaging (MRI) of the brain and orbits: MRI is essential to confirm optic nerve inflammation and to exclude other causes such as compressive lesions or demyelinating plaques suggestive of multiple sclerosis ⁶.
• Visual function tests: Visual acuity, colour vision, and visual field testing help document the extent of visual impairment.
• Ophthalmological examination: Slit-lamp examination with dilated pupils to exclude uveitis or other ocular inflammatory conditions ⁵.
• Blood tests: To exclude infectious or inflammatory causes if clinically indicated, although not routinely required for typical optic neuritis ⁶.
• Referral to ophthalmology and neurology specialists: For further assessment and confirmation of diagnosis, including consideration of lumbar puncture or other investigations if atypical features are present ⁶.

These investigations help confirm optic neuritis and exclude other causes such as uveitis, glaucoma, or compressive optic neuropathies.