Neuro-ophthalmology: double vision, optic nerve disease and visual loss

Why these symptoms are taken seriously

Vision depends not only on the eye but on the optic nerve and the pathways that carry signals to the brain, and eye movement depends on nerves running through the skull. A change in vision or in eye movement can therefore be the first sign of a problem outside the eye, including raised pressure in the head, inflammation, a blood supply problem or a stroke.

This does not mean every symptom is dangerous. Many causes are benign and treatable. It does mean that certain combinations, particularly sudden onset symptoms or symptoms with headache, weakness or slurred speech, need assessment straight away rather than a routine appointment.

What an assessment involves

• Vision, colour vision and pupil reactions, which give direct information about the optic nerve
• Eye movements and alignment in all directions of gaze
• Examination of the optic discs after dilation, looking for swelling or pallor
• Visual field testing to map where vision is missing
• Optical coherence tomography of the optic nerve where indicated
• Blood pressure and general medical review, and referral for brain imaging or neurological assessment when required

Working with other specialists

Many of these conditions are managed jointly. Standard Eye Specialist Hospital carries out the ophthalmic assessment, including visual fields, optic nerve imaging and dilated examination, and where scans or neurological or physician care are needed these are arranged with the appropriate service.

Frequently asked questions

Can an eye examination detect a brain problem?

Sometimes. The optic disc is the only part of the nervous system visible directly, so swelling or pallor there, along with pupil and field findings, can point to a problem inside the head that needs a scan.

Do I need a brain scan for every case of double vision?

No. The need for imaging depends on the pattern, how it started, your age and other symptoms. Your ophthalmologist will explain whether a scan is needed in your case.