Myopia

What's going on?

Short sight in itself is not pathological. Light is focused too far in front of the retina, either because of the excessive focusing power of the front of the eye or because the eye is too long. The latter condition is pathological because the sclera are abnormally stretchy and degenerative. These eyes are highly prone to retinal detachments and may develop numerous areas of chorioretinal atrophy.

If I examine the patient, what will I find?

You may see patches of atrophy in the retina or a large area of circumferential atrophy surrounding the optic disc (peripapillary atrophy).

What if I've diagnosed it?

Myopia in itself is not a problem. The patient's spectacle prescription will give you an idea of how bad their myopia is. More than around −5 is quite myopic. Alternatively, look at their spectacles – if the lenses are thick, the patient is quite short-sighted. Remember that if the spectacles magnify, they are for long-sighted people.

What will the hospital do?

If the patient is referred to hospital, they will probably have either a retinal tear or a myopic maculopathy.

What to tell the patient

The major risk is retinal detachment and patients should be warned about the symptoms. Some patients develop a maculopathy where their central vision is progressively and irreversibly reduced.

Problems that may arise, and how to deal with them

If the patient develops flashes and floaters they should attend their optician or the hospital eye service as a matter of urgency as these are symptoms of a potential retinal detachment.

Patients may ask you about laser refractive surgery. This is an evolving field, and not suitable for everyone. Generally, the outcome is less predictable for higher refractive errors, and there are risks. These can be discussed at a laser refractive centre, and there is much information on the internet.