Cataracts

Question 1

Define cataracts.

Answer 1

Cataract is the opacification of the crystalline lens that results from the normal ageing process, trauma, metabolic disorders (hereditary or acquired), medications, or congenital problems. It is the most common cause of curable blindness in the world.

Question 2

Explain the aetiology/risk factors of cataracts.

Answer 2

Age >65 years
Smoking
Long-term UV exposure
Diabetes mellitus
Eye trauma
Long-term ocular corticosteroid use
FHx of congenital cataract or congenital influences (e.g., toxins)
Uveitis

Question 3

Summarise the epidemiology of cataracts.

Answer 3

The WHO estimates that cataracts currently account for 51% of reversible blindness worldwide, which translates to about 20 million people. There are estimates that by 2020, the number of people with moderate or severe vision impairment caused by cataracts could be as high as 57 million, with an estimated 13 million people blind because of cataracts.

Question 4

Recognise the presenting symptoms of cataracts. Recognise the signs of cataracts on physical examination.

Answer 4

Subjective decrease in vision
Blurred or cloudy vision
Glare
Washed-out colour vision
Reduced visual acuity
Defects in the red reflex

Question 5

Identify appropriate investigations for cataracts and interpret the results.

Answer 5

Dilated fundus examination
Measurement of intraocular pressure
Glare vision test
Slit lamp examination of the anterior chamber