Cataracts

Question 1

What are cataracts?

Answer 1

Opacification of crystalline Lens

Question 2

How are opacities classified?

Answer 2

Classification:
Red Reflex – Immature cataracts
No red reflex or visible fundus – Dense Cataracts
Anterior/Posterior Polar cataracts – Localised opacities in visual axis
Dot Opacities – Normal or Fast developing in DM

Question 3

What is the aetiology of cataracts?

Answer 3

Normal Aging process – Crystallin protein changes affect refraction in the lens, reduce clarity (MOST COMMON)

Pathological  
Trauma  
Metabolic  
Infection - (E.g. Rubella) 
Medication 
Congenital

Question 4

What are the risk factors of cataracts?

Answer 4

>65 
Smoking 
LT UV exposure 
DM 
Eye trauma 
LT ocular corticosteroids 
FH (congenital) 
Uveitis

Question 5

What is the epidemiology of cataracts?

Answer 5

COMMON – Responsible for 51% of reversable blindness in world

Most common causes blindness: Cataracts, Vit-A deficiency, trachoma, onchocerciasis

Prevalence: 20% 45-65, 75% >65s

High Socioeconomic impact – Two people out of workforce per case

Question 6

What are the symptoms of cataracts?

Answer 6

Gradual blurring of vision

Washed out colour vision (Yellow hue to cataract proteins reduces colour richness – esp. Blue)

Dazzle/Glare

Inadequate glasses prescription

Question 7

What are the signs of cataracts?

Answer 7

Defects in red reflex

Reduced Visual Acuity

Question 8

What investigations are done to diagnose cataracts?

Answer 8

Fundoscopy (Fundus and Optic nerve should be normal)

Tonometry (IOP normal or elevated if with glaucoma)

Glare Vision Test

Slit Lamp Anterior chamber exam - Cataracts visible