Eye condition library
Eye conditions, explained clearly
What each condition is, the symptoms to watch for, who is at risk and how it is treated. Written from National Eye Institute, American Academy of Ophthalmology and American Optometric Association guidance, with sources on every page.
Some symptoms can't wait
Sudden vision loss, a curtain over your vision, a sudden shower of floaters or flashes, a painful red eye, or a chemical in the eye need care today. Read the eye emergencies guide.
Focusing problems
Myopia (nearsightedness)
Far objects look blurry. Rising fast in children worldwide.
Read more →Hyperopia (farsightedness)
The eye works harder to focus, especially up close.
Read more →Astigmatism
An unevenly curved cornea or lens blurs vision at all distances.
Read more →Presbyopia
The age-related loss of close-up focus that starts in the 40s.
Read more →Eye diseases
Cataract
Clouding of the eye's lens. Common with age and fixable with surgery.
Read more →Glaucoma
Optic-nerve damage that steals side vision with no early warning.
Read more →Age-related macular degeneration (AMD)
Damage to the macula that blurs central vision in older adults.
Read more →Diabetic retinopathy
Diabetes damages retinal blood vessels. Yearly dilated exams catch it early.
Read more →Everyday problems
Dry eye
Too few or poor-quality tears cause burning, grittiness and blur.
Read more →Digital eye strain
Tired, dry, blurry eyes after long screen sessions.
Read more →Pink eye (conjunctivitis)
Red, itchy or sticky eyes from viruses, bacteria or allergies.
Read more →Floaters and flashes
Usually harmless specks, but a sudden shower can mean a torn retina.
Read more →Children's vision
Amblyopia (lazy eye)
One eye does not develop full vision in childhood. Best treated early.
Read more →Strabismus (crossed or turned eyes)
The eyes do not line up and point in different directions.
Read more →