Refractive Errors

If you have trouble seeing nearby or distant objects, you may have long-sightedness or short-sightedness. These are refractive errors, meaning the lenses in your eyes aren’t focusing light correctly.

Refractive errors affect many people, and they can lead to other problems if you struggle to see when performing everyday tasks. This page will help you understand these conditions and how to treat refractive errors.

What are refractive errors?

If the shape of your eye changes, it alters how light rays bend and focus on the retina. When the eye can’t focus light to create a sharp image, it results in a refractive error. These can range from mild to severe.

There are four common types of refractive error:

Short-sightedness (myopia), also known as near-sightedness
Long-sightedness (hyperopia), also known as far-sightedness
Astigmatism, where your vision looks blurred, usually at all distances, due to an elongated eyeball shape
Presbyopia, or problems focusing on close objects as you age

Our videos below discuss each of these conditions in more detail.

Symptoms

Problems with refractive errors can be subtle at first, as the condition may develop slowly. You may not notice these symptoms until they are more pronounced or start affecting your daily life.

Symptoms can include:

Trouble focusing when reading or using a computer
Glare or halo around bright lights
Eye strain (tired, sore eyes)
Double vision (diplopia)
Hazy or blurred vision
Headaches
Squinting

Refractive error conditions are common, so it is important to get your eyes examined every two years. If you already wear glasses or contact lenses and experience any of these symptoms, you might need a new prescription.

Types

Short-sightedness

If you are short-sighted, objects that are far away may look blurred. This often happens when your eye is too long, rather than spherical. Slight short-sightedness can cause minor blurring, while a severe condition may make it very hard to see objects at long distances. However, you should be able to see close objects clearly, unless you have another eye condition.

Long-sightedness

People with long-sightedness have problems seeing close objects, as they look blurred or out of focus. You may experience this if your eye is too short, your cornea is too flat, or you have another issue with the lens in your eye. If you are long-sighted, you may have difficulty reading or using a screen. These tasks might be easier if you place the objects further away, for example, at arm’s length.

Astigmatism

Astigmatism occurs when your eye has an irregular rugby ball shape instead of being smooth and evenly curved. This irregularity causes light to focus on multiple points of the retina rather than a single point, causing blurred or distorted vision. You can be born with astigmatism, or it can develop later in life.

Presbyopia

Presbyopia causes focusing issues as you get older, usually from middle age. It occurs when the lens in your eye hardens, meaning it is less able to change shape to focus on nearby objects. You may have another refractive error (as above) along with presbyopia.

Causes

Our eyes can naturally vary in shape or density, especially during childhood or when we reach our 40s. Anyone can develop a refractive error, but they frequently run in families. For example, people often inherit myopia, and it’s generally discovered before you reach adulthood.

For some people, a problem with the shape of the cornea (the eye’s transparent outer layer) causes refractive errors. In others, the length of the eyeball may grow too short or long. The crystalline lens inside the eye can lose clarity in later life, affecting your sight.

Diagnosis

Ophthalmologists (eye specialists) check for refractive errors during a standard eye test. We can do this by asking you to read letters from a chart and checking how well different lenses help your vision. We may also use dilating eye drops to rule out other eye conditions.

If you need corrective lenses, you’ll get a prescription for glasses and/or contact lenses. However, some people choose to avoid contact lenses, as they carry some risks with long-term use. Our specialist clinic offers more permanent treatment options, as we explain below.

Correcting refractive errors

Some types of surgery change the shape of your cornea to fix refractive errors. At Oculase, we can help you decide if surgery is the best option.

Surgical options include:

Laser eye surgery, such as LASIK or PRK
Implantable contact lenses
Refractive lens exchange (lens replacement surgery) after 50 years old

If you have had lens replacement or cataract surgery, you may need a refractive secondary lens implant. This procedure can reduce your reliance on glasses.

Our blog – Presbyopia treatment: Laser vision correction and refractive lens exchange – covers the options for presbyopia in more detail.

Book an appointment

If you are experiencing the symptoms of a refractive error, speak to one of our expert ophthalmologists. Our specialists will examine your eye and complete a full assessment. We will also arrange further testing if it is needed and treatment.

We offer private vision correction services for refractive errors and other eye conditions. We know it is important to be aware of all your treatment options so you can make an informed decision about your eye care.

For any questions about our eye treatments, contact us to talk to a specialist.

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Frequently asked questions

Many people get refractive errors as they are one of the most common types of visual impairment. In the UK, roughly one in three people have a refractive error.

You are more likely to experience a refractive error if you have a family member with one. You should attend regular eye exams to identify any problems early. People over 40 are more at risk of presbyopia.

We can’t do anything to reduce the risk of these conditions developing. However, early treatment can prevent them from worsening and possibly avoid some vision loss.