There are minor eye conditions which can affect almost anyone, such as being short-sighted or having dry eyes. However, there are conditions which can indicate deeper, underlying health problems.
Shortsightedness and longsightedness are common eye conditions that mean light does not focus correctly on the retina. Both can be easily corrected using prescription glasses or contact lenses.
Astigmatism occurs when the surface of the cornea or lens is not spherical. This means the eye is unable to bring a point or object into sharp focus.
It's a perfectly natural condition that eventually affects everyone. But, because the effects are gradual, you may not notice that anything is wrong with your eyesight initially.
Flashes and floaters happen because of changes in the vitreous humour, the clear, jelly-like substance that fills the inside of your eyeball. This shrinks as you get older, slowly pulling away from the eye's surface.
Dry eyes, or dry eye syndrome, is a fairly common eye condition. It is caused when the eyes either don't make enough tears, either in quality or quantity, or the tears evaporate too quickly.
A common condition, conjunctivitis is an inflammation of the thin layer that covers the white of the eye and the inside of the eyelids. Symptoms include red and sore eyes, which can also become sticky or watery.
Blepharitis is a common, non-sight-threatening inflammation of the eyelash follicles causing itching, irritation and inflamation of the rims of the eyelid. GPs say it accounts for 5% of all eye problems they see.
A cataract is a clouding of the lens in the eye, appearing rather like a frosted glass coating that scatters light, causing blurring and lack of definition.
People with diabetes can experience a range of eye conditions, including damage to the retina and even loss of sight. Diabetic retinopathy causes damage to the blood vessels in the retina.
Macular degeneration is a painless eye condition that causes you to lose central vision, usually in both eyes. It's one of the leading causes of severe vision loss in the western world.
Glaucoma is the name given to a group of eye conditions which affect the optic nerve as it joins the back of the eye. Most types have no symptoms, so a regular eye test is the only way to know you have the condition.
Retinoblastoma is a rare form of eye cancer which generally affects children under five years of age. It is treatable, but if signs are noticed they must be checked out quickly.