Ophthalmologists can reveal problems away from the visual

By Mr Peter Gray MA LLM FRCS FRCOPHTH MFFLM, ophthalmologist and director of Eye-Law Chambers

Leonardo da Vinci: Notebooks

[ALTHOUGH THE CLINICAL PRACTICE of modern ophthalmology was unknown to Leonardo, his comment is very relevant today, when ophthalmologists can detect signs in the eyes which reflect pathologies elsewhere in the body. The following cases are illustrative:

A patient with a traumatic brain injury has difficulty in mobilising and performing the activities of daily living

In this case the eye can be likened to a camera which detects the image of the surroundings, generating nervous impulses which are conveyed via many individual nerve fibres in the optic nerve from the eye to the primary visual cortex of the brain located at the back of the head. Here the brain processes the nervous impulse to generate the perceived image. The nerve fibre pathway from the eye to the brain may be damaged anywhere in its path – leading to the development of a visual field defect, such as not being able to see the same half of the visual world in each eye.

There are other parts of the brain which process higher visual function, such as the perception of colour, stereopsis (depth perception) and the ability to recognise faces. Damage involving those parts of the brain results in the loss of the relevant function. The ophthalmologist can plot the visual fields – and some defects are a bar to holding a driving licence – and assess colour and stereoscopic vision.

The patient with double vision (diplopia)

The ophthalmologist can assess the diplopia and determine the cause, which may relate to the extraocular muscles which move the eye, their nerve supply or entrapment in orbital fractures – as well as any associated injuries to the eye and the eyelids.

The patient with numerous fractures who develops blurry vision

The ophthalmologist can examine the retina (sensory membrane of the eye) for the presence of fat emboli in the retinal blood vessels.

The assessment of suspected child abuse

The ophthalmologist can examine the retina with regard to the presence of retinal haemorrhages which are suggestive of ‘shaken baby syndrome’.

The ophthalmologist can thus contribute to the holistic assessment of an individual with polytrauma, as well as reporting on specific ocular pathologies. At Eye Law Chambers we are a group of ophthalmologists with medico-legal expertise who all have a wide experience in general ophthalmology as well as specialist interests. q

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