Introduction

Neuro-ophthalmology deals with visual disorders caused by disease of the nervous system. The principles of diagnosis are the same as in any other branch of neurology; a good history with a directed examination. In addition, a sound knowledge of the anatomy and physiology of the visual sensory and oculomotor systems is essential.

Most referrals come from ophthalmologists who either detect an obvious abnormality of the optic nerve, or eye movements, or they cannot explain the visual symptoms from their examination of the eye. Neurologists should have a close working relationship with the ophthalmology department so there are clear pathways for how referrals can be made. Also, it is important to make friends with:

Orthoptists: who perform detailed measurements of eye movements, which can be subsequently repeated to assess change. In addition, they can help to correct double vision with prisms and can advise when corrective strabismus surgery may be indicated.

Visual field technicians: because a formal visual field assessment can clarify the nature of the presenting problem as well as provide a baseline record to assess progress.

Photographers: who can perform retinal photography and retinal imaging. Any optic disc that is thought to be abnormal should be photographed at the first presentation to provide a clear baseline record. Photographs are a lot easier to communicate with than scribbled diagrams in the notes, and can be very useful for any subsequent presentations or case reports.

Retinal imaging techniques such as optical coherence tomography (OCT) are widely used by ophthalmologists but are not particularly helpful in making a neuro-ophthalmological diagnosis. However, OCT can measure the thickness of the retinal nerve fibre layer, so providing a quick and cheap marker of axonal integrity in diseases such as multiple sclerosis. Also, OCT may help in differentiating a maculopathy from an optic …