CATARACT

Question 1

What is a cataract?

Answer 1

An opacity of the crystalline lens in the eye.

Question 2

What are the most common types of cataracts?

Answer 2

Nuclear sclerosis - most common. Clouding of the central lens and myopic shift

Posterior subcapsular - more focal opacity of the posterior lens

Polar - localized, commonly inherited, lie in the visual axis

Dot opacities: common in normal lenses, also seen in diabetes and myotonic dystrophy

Question 3

What is the most common cause of cataracts?

Answer 3

Age - UV light exposure

Question 4

What are the systemic diseases associated with cataracts?

Answer 4

Diabetes
Hypocalcaemia
Galactosaemia
Wilson's disease
Myotonic dystrophy

Question 5

What are the ocular pathologies associated with cataracts?

Answer 5

Trauma/postoperative
Uveitis
High myopia
Topical steroids

Question 6

What are the medications associated with development of cataracts?

Answer 6

Systemic steroids - classically associated with posterior subscapular cataract
Anticholinesterase
Antipsychotics
Amiodarone

Question 7

What are the symptoms associated with cataracts?

Answer 7

Loss of vision - gradual over 6-12 months
Glare - poor vision in bright light
Monocular diplopia (double vision in one eye) - rare

Question 8

What are the signs associated with cataracts?

Answer 8

Lens opacity
Inflammation
Pseudo-exfoliation syndrome - build up of proteins that can block the trabecular meshwork
Anterior segment dysgenesis

Question 9

How is cataract treated?

Answer 9

Surgical removal

Question 10

What happens in cataract removal surgery?

Answer 10

The lens is accessed via the cornea and then the capsule that it sits in. It is then broken up using hydrodissection and high frequency ultrasound (phacoemulsification). The lens material is aspirated and replaced with an artificial acrylic intraocular lens.

Question 11

Post a cataract removal operation, what medications will patients need to take?

Answer 11

Anti-inflammatory (steroids)

Antibiotic drops

Question 12

What are the complications associated with cataracts surgery?

Answer 12

Endophthalmitis - affects about 0.1% of intraocular surgeries

Raised IOP

Inflammation

Retinal detachment

Cystoid macular oedema

Posterior capsule opacification

Question 13

What are the symptoms of endophthalmitis?

Answer 13

Early - very painful red eye with a hypopyon (pus in the anterior chamber)

Late - chronic inflammation with or without hypopyon

Question 14

Each one of the following predisposes to cataract formation, except:

Down’s syndrome

Hypercalcaemia

Diabetes mellitus

Long-term steroid use

Congenital rubella infection

Answer 14

Hypercalcaemia

Hypocalcaemia, rather than hypercalcaemia, predisposes to cataract formation