In its mildest form, blurred vision can include mild blurring of objects at a distance or close up. At its most severe, blurred vision can affect your ability to look after yourself and compromise your quality of life.
Blurred vision can be caused by many different conditions, so it is always best to get your eyes checked out by an expert.
Causes of blurred vision
There are many different eye problems and conditions that can cause blurred vision. These include:
Refractive errors that cause blurred vision include:
- Long-sightedness: causes blurred vision when viewing objects close up; such as when reading a book or using a computer.
- Short-sightedness: causes blurred vision when viewing objects at a distance; such as when watching television or driving.
- Astigmatism: causes blurred vision when viewing objects at any distance.
Cataracts are a clouding of the lens in your eye. At first any blurred eyesight may be almost imperceptible; however cataracts can eventually result in severe blurred vision that has a major impact on your independence.
If you have had a cataract removed and your blurry vision reoccurs, ‘posterior capsule opacity’ also known as a ‘secondary cataract’ may be the cause.
Diabetic retinopathy is a condition associated with diabetes. High blood sugar levels cause damage to the retina (the focusing surface at the back of the eye). The final stage of diabetic retinopathy known as ‘macular oedema’ can cause blurred vision.
An epiretinal membrane is a thin, fibrous layer that forms over the retina (the focusing surface at the back of the eye). It acts like a film that partially blocks the light entering your eye, which results in blurred vision.
Eye infection, inflammation or injury
Many people suffer blurred vision as a result of an eye infection or injury. Eyelid and eyelash problems can sometimes cause blurred vision, as can the common eye infection conjunctivitis.
Keratoconus is an eye disease that results in a conically shaped cornea. As the cornea does much of the eye’s focusing, the irregular shape can cause blurred vision.
Macular degeneration and macular holes
The macula is the central part of the retina at the back of your eye. It allows you to see detail, colour, and things directly in front of you. Macular degeneration and macular holes damage the macula, causing central vision to become blurred.
A pterygium is a benign growth that occurs on the surface of the eye. Sometimes, a pterygium can grow onto the cornea. If this occurs, it can alter the shape of the cornea, causing blurred vision.
A detached retina is a serious medical emergency that can cause sudden blurred vision. It may also cause a number of other symptoms such as flashes, floaters and sudden blindness.
Retinal vein occlusion
If the blood vessels that feed the retina (the focusing surface at the back of the eye) become blocked, it is known as a retinal vein occlusion. This can cause sudden blurred vision and also sudden blindness.
If blood leaks into the vitreous ‘gel’ that fills your eye, it can block the light that enters your eye causing blurred vision. Vitreous haemorrhage can be caused by trauma or injury, or it may be a result of an eye condition such as diabetic retinopathy.
Treating blurred vision
Treatment for blurred vision will depend entirely on what is causing it. Refractive errors such as long-sightedness, short-sightedness and astigmatism can now be permanently corrected in most people thanks to iLASIK laser eye surgery.