Correcting refractive errors

Refractive errors occur when the eye cannot focus the image onto the retina. The most common refractive errors are myopia (short-sightedness), hyperopia (long-sightedness), astigmatism and presbyopia. In most cases, refractive surgery, also known as laser eye surgery, corrects these vision problems.

Find out more about refractive surgery.

Refractive errors

Myopia (Short-sightedness)

Myopia is a refractive error that occurs when your eye is too long compared to the curvature (focusing power) of your cornea, or when the cornea is more curved, so light focuses short of the retina. This means you cannot see distant objects clearly, such as the numbers on the front of buses. Corneal refractive surgery can correct this by changing the shape of the cornea so that its focusing power is matched to the length of the eye. Laser eye surgery can correct short-sightedness.

Hyperopia (Long-sightedness)

A refractive error that occurs when your eye is too short compared to the curvature (focusing power) of your cornea, or when the cornea is less curved, so light focuses behind the retina. When younger, many hyperopic eyes can self-focus by utilising the 'zoom' intended for reading, to compensate for the distance blur. Laser eye surgery can correct long-sightedness.

Astigmatism

Astigmatism occurs when your cornea is more oval shaped (like a rugby ball) than a sphere. The result of this refractive error is that light is focused at two different planes inside your eye. Images appear blurred or ghost images can result. Approximately half of all people with myopia or hyperopia have astigmatism as well. Refractive surgery can correct astigmatism, whether it is accompanied with myopia, hyperopia or presents alone.

Presbyopia (ageing eyes/reading glasses)

Everyone develops the refractive error known as presbyopia during their life. Most people, whether they have previously worn glasses or not, experience the symptoms of presbyopia in their forties. Effectively, the zoom system that allows your eyes to change focus from distance to near becomes weaker. Your ability to read small print (i.e. newspapers) diminishes and you require different lenses for focusing on close or distant objects. Traditionally, people have used reading glasses, bifocals or varifocals, to correct this, but refractive surgery offers a permanent solution to this eye condition.

Chat to one of our patient consultants for more information on these eye conditions or on correcting them with refractive surgery. You can call us on 0845 409 2 409 or contact us via this website.