Eye diseases and disorders

This week we are looking at eye diseases or disorders at least 2.2 billion people worldwide have some form of vision impairment or eye condition that’s about 28% of the population. This figure doesn’t include things like dry eye or conjunctivitis or any other condition that doesn’t affect sight, if it did the percentage would be more like 50% of the population.

Eye diseases include any condition that affects the cornea, lens, retina, optic nerve, eyelids, or the visual pathways in the brain. Some are mild and temporary; others can cause permanent vision loss if untreated.

Eye conditions for into one of eight categories these are the following.

Refractive Disorders (Most Common Worldwide)

These affect how light bends in the eye.

• Myopia (short‑sightedness) – distant vision blurred
• Hyperopia (long‑sightedness) – near vision blurred
• Astigmatism – uneven focus due to irregular cornea
• Presbyopia – age‑related loss of near focus (40+)

Treatment: glasses, contact lenses, or refractive surgery.

Lens Disorders

Cataracts

Clouding of the lens causing blurred or dim vision.

• Extremely common with age
• Treated with cataract surgery (one of the safest surgeries worldwide

Retina Disorders

These affect the light‑sensitive layer at the back of the eye.

Age‑Related Macular Degeneration (AMD)

• Damages central vision
• Leading cause of blindness in older adults
• Two types: dry and wet

Diabetic Retinopathy

• Caused by diabetes damaging retinal blood vessels
• Can lead to blindness if untreated

Retinal Detachment

• Retina pulls away from the back of the eye
• Medical emergency
• Symptoms: flashes, floaters, curtain over vision

Macular Hole / Macular Pucker

• Distortion or loss of central vision

Optic Nerve Disorders

Glaucoma

• Damage to the optic nerve, often due to high eye pressure
• Causes gradual, irreversible vision loss
• Requires lifelong management

Optic Neuritis

• Inflammation of the optic nerve
• Often linked to autoimmune conditions

Corneal Disorders

Keratoconus

• Cornea thins and bulges into a cone shape
• Causes distorted vision
• Treated with cross‑linking, contacts, or corneal transplant

Corneal Ulcer

• Open sore, usually from infection
• Painful and urgent to treat

Eyelid & Surface Disorders

Blepharitis

• Inflammation of eyelid margins
• Causes irritation, crusting, dryness

Conjunctivitis (Pink Eye)

• Viral, bacterial, or allergic
• Causes redness, discharge, irritation

Dry Eye Disease

• Very common
• Caused by poor tear quality or quantity

Childhood Eye Disorders

Amblyopia (Lazy Eye)

• Brain favours one eye
• Treatable if caught early

Strabismus (Eye Turn)

• Eyes misaligned
• May require glasses, exercises, or surgery

Rare but Serious Conditions

·       Uveitis – inflammation inside the eye

·       Retinoblastoma – childhood eye cancer

·       Graves’ Eye Disease – autoimmune swelling behind the eyes

·       Idiopathic Intracranial Hypertension – pressure on optic nerve

When it comes to our eyes people should seek immediate help if they experience any of the following

• Sudden vision loss
• Flashes or a curtain over vision
• Severe eye pain
• Sudden double vision
• Chemical injury

These can indicate emergencies like retinal detachment, acute glaucoma, or infection.