Cataracts Flashcards
What is cataracts?
When the lens gradually opacifies (becomes cloudy).
This reduces the light entering the eye and visual acuity.
What is the role of the lens?
To focus light on the retina
What is the lens held in place by?
It is held in place by suspensory ligaments attached to the ciliary body.
What is the role of the ciliary body?
To change the shape of the lens by contracting/relaxing.
When the ciliary body contracts, it releases tension on the suspensory ligaments, and the lens thickens.
When the ciliary body relaxes, the suspensory ligaments tension, and the lens narrows.
What is the lens nourished by?
Aqueous humour
What exam is used to test for congenital cataracts?
Red reflex test
What is the the leading cause of curable blindness worldwide?
Cataracts.
What is the most common risk factor of cataracts?
Normal ageing process
Other risk factors for cataracts?
- Smoking
- Alcohol
- Trauma
- Diabetes mellitus
- Long-term corticosteroids
- Radiation exposure
- Myotonic dystrophy
- Metabolic disorders: hypocalcaemia
Are cataracts symptoms usually symmetrical or asymmetrical?
Asymmetrical (both eyes affected separately)
Presentation of cataracts?
- Slow reduction in visual acuity
- Progressive blurring of the vision
- Colours becoming more faded, brown or yellow
- Starbursts (halos) can appear around lights, particularly at night
What is a key examination finding in cataracts?
Loss of the red reflex
Mx of cataracts?
1) No intervention may be necessary if the symptoms are manageable.
2) Non-surgical e.g. stronger glasses/contact lens, encouraging the use of brighter lighting
3) Cataract surgery
Key investigation in cataracts?
Slit lamp exam
What does cataracts surgery involve?
Removing the cloudy lens and replacing this with an artificial one.
