Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
23 Cards in this Set
- Front
- Back
|
What causes anterior subcapsular cataract? |
Fibrous metaplasia of the lens epithelium |
|
|
Which kind of cataract affects vision the worst and why? |
Posterior subcapsular because it is the closest to the nodal point of the eye. Near vision is frequently impaired more than distance |
|
|
What causes nuclear cataracts? |
Ageing! |
|
|
Posterior subcapsular cataract |
|
|
Posterior subcapsular cataract |
|
|
Nuclear cataract |
|
|
Cortical cataract - often starts as clefts and vacuoles. Initially in inferonasal quadrant |
|
|
Christmas tree cataract, uncommon May be solitary or associated with other opacities |
|
|
Early diabetic snowflake cataract - rare, occurs in young pts, may resolve spontaneously or mature in a few days |
|
|
Advanced diabetic snowflake cataract |
|
|
What systemic diseases can cause cataract? |
DM, myotonic dystrophy, atopic dermatitis, NF-2 |
|
|
Posterior subcapsular caused by myotonic dystrophy; 90% develop fine opacity in 3rd decade and become disabling stellate PSC by 5th decade |
|
|
Anterior subcapsular shield cataract characteristic of atopic dermatitis |
|
|
What kind of cataract is seen in NF-2 |
PSC, cortical or mixed |
|
|
What are some secondary causes of cataract? |
Anterior uveitis, high myopia, acute ACG, hereditary fundus dystrophies |
|
|
What lens opacity is characteristic of acute ACG |
Glaucomflecken |
|
|
What kind of cataract does pathological myopia cause? |
PSC and early onset nuclear sclerosis |
|
|
What kind of cataract do hereditary fundus dystrophies cause? |
PSC |
|
|
Penetrating trauma cataract |
|
|
Blunt trauma cataract - flower-shaped |
|
|
Lightning/electric shock cataract - causes anterior/posterior iridescent opacities with stellate pattern |
|
|
infrared radiation - true exfoliation of anterior lens capsule |
|
|
Ionising radiation - forms tumours that cause PSC months or years later |
