AED - Cataracts II & III- PAP Week 1 Flashcards
What are the three types of senile cataracts?
Nuclear
Cortical
Posterior subcapsular
Does smoking increase or decrease the risk of senile cataract? Which types (2)?
Increases risk of nuclear/cortical cataracts
What is the most common form of senile cataracts?
Nuclear
How does senile cataracts appear and what is a possible casue?
Appears like a yellow haze in the nucleus and posterior cortex
Possible cause is light damage to the lens proteins
What are 4 visual symptoms of senile cataracts?
Glare
Light loss
Polyopia
Blur
What refractive shift may occur with cataracts? What is indicative of nuclear sclerosis?
Myopic shift
-1.00D/4 years is indicative of nuclear sclerosis
Why may mydriasis improve vision in those with cataracts?
Light may bypass the cataract
Why may some hyperopes find their vision improving when they have cataracts?
The myopic shift caused by the cataract may correct their hyperopia
What is the appearance of cuneiform cortical cataract and what causes this?
Wedges/spokes
Due to water accumulation between fibres, possibly due to UVB
Is cuneiform cortical cataract central or peripheral and what effect does it have on vision?
Peripheral location, minor effect on vision
Does cuneiform cortical cataract cause hyperopic or myopic shift?
Hyperopic
What happens to the lens itself in cuneiform cortical cataract (aside from its appearance)? What can it result in?
Lens growth causing swelling - intumescence
Possible pupil block
How does cuneiform cortical cataract progression appear (2)?
By expansion and coaslescing of spokes
Does miosis or mydriasis improve VA in cuneiform cortical cataract?
Miosis
What is the least common form of senile cataract?
Posterior subcapsular
What makes posterior subcapsular cataracts visually the most debilitating?
Its location
Does miosis or mydriasis improve VA in posterior subcapsular cataract?
Neither
What is the cause of age-related posterior subcapsular cataract?
Thinning of the posterior capsule resulting in greater H2O influx
What causes the lacey apeparance of the posterior subcapsular cataract opacity?
Migration of bow cells
What medication can cause posterior subcapsular cataract?
Corticosteroids
What are three possible consequences of cataracts over time (consider the lens swelling)?
Glaucoma
Pupil block
Uveitis due to capsular rupture
What is the most common cataract intervention? What else can be done and why is it generally done (neonates)? What kinds of cataracts specifically is this done to (2) and in what age group?
Surgery with aphakia/pseudophakia
Dilate neonates with homatropine for nuclear or anterior capsular (but not posterior subcapsular)
Done to prevent amblyopia onset