cataracts

Question 1

what is a cataract?

Answer 1

a common eye condition where the lens of the eye gradually opacifies i.e. becomes cloudy the cloudiness makes it more difficult for light to reach the retina → blurred vision

Question 2

what causes cataracts?

Answer 2

commonly a normal ageing process

Question 3

what are the other possible causes of cataracts?

Answer 3

• smoking
• increased alcohol consumption
• trauma
• DM
• long-term corticosteroids
• radiation exposure
• myotonic dystrophy
• metabolic disorders: hypocalcaemia

Question 4

how to pts with cataracts typically present?

Answer 4

gradual onset of:

• reduced vision
• faded colour vision: making it more difficult to distinguish different colours
• glare: lights appear brighter than usual
• haloes around lights

Question 5

what are the signs of cataracts?

Answer 5

defect in the red reflex

Question 6

what are the investigations for cataract?

Answer 6

1. ophthalmoscopy: done after pupil dilation.
   
   • findings: normal fundus and optic nerve
2. slit-lamp exam: visible cataract

Question 7

what are the classifications of cataract?

Answer 7

1. nuclear
   
   • _{change lens refractive index, common in old age}
2. polar
   
   • _{localised, commonly inherited, lie in visual axis}
3. subcapsular
   
   • _{due to steroid use, just deep to lens capsule, in visual axis}
4. dot opacities
   
   • _{common in normal lenses, seen in DM and myotonic dystrophy}

Question 8

what is the non-surgical mx for cataracts?

Answer 8

in early stages, age-related cataracts can be managed conservatively by:

• prescribing stronger glasses/contact lens
• encourage use of brighter lighting

helps optimise vision but doesn’t slow progression

Question 9

what is the surgical mx of cataracts?

Answer 9

the only effective treatment

remove cloudy lens and replace with artificial one

Question 10

what are the complications following cataract surgery?

Answer 10

1. posterior capsule opacification: thickening of lens capsule
2. retinal detachment
3. posterior capsule rupture
4. endophthalmitis: inflammation of aqueous +/- vitreous humour

Question 11

A 77-year-old male presents to the Emergency Department with an exquisitely painful red eye and reduced vision in his right eye. He has a past medical history of rheumatoid arthritis and cataracts, for which he had an operation 5 days ago.

Dx?

Answer 11

This is a presentation of endophthalmitis with a red eye and reduced vision following intraocular surgery.