Eye conditions and diseases

Understanding common causes of vision loss

Vision loss can be caused by eye problems present from birth, conditions that appear later in life, infections, or environmental factors. Learn more about the most common eye conditions and diseases that can cause vision loss. 

Medical scan of eye with age-related macular generation

Age-related macular degeneration (AMD)

Age-related macular degeneration (AMD) is the most common cause of vision loss among Canadians over the age of 50.
Close-up of an eye with cataracts

Cataracts

Cataracts occur as your lenses naturally harden with age and may turn cloudy. The effect can be like looking through a dirty car windshield.
Medical scan of eye with diabetic retinopathy

Diabetic retinopathy

Diabetic retinopathy occurs when elevated sugar (glucose) levels in your blood cause the blood vessels in the eye to swell and leak in the retina.
Woman administering eye drops in another woman’s eye

Dry eye

Dry eyes happens when your eyes don't produce enough tears, or tears evaporate too quickly.
Image of floaters against the sky

Floaters and flashing lights

Floaters are dark specks in the form of dots, circles, lines, or cobwebs. Flashing lights can appear as lights going on and off, especially to one side.
Image of man’s eyes, one of which is affected by glaucoma

Glaucoma

Glaucoma occurs due to damage to the optic nerve. Over time the disease develops into a loss of peripheral (side) vision.
Amblyopia (commonly known as “lazy eye”) happens when the vision in one eye doesn't develop properly in early childhood

Lazy eye (amblyopia)

Amblyopia (commonly known as “lazy eye”) happens when the vision in one eye doesn't develop properly in early childhood.
Image of child who is cross eyed

Turned eyes (strabismus)

Strabismus is the medical term for misalignment of the two eyes that are not straight. It occurs in at least five per cent of the population.