Posterior / Nuclear Cataract Flashcards Preview

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Flashcards in Posterior / Nuclear Cataract Deck (9):

Describe posterior sub capsular (cupuliform) cataract

(location, appearance, what causes it?, does it affect vision?)

- located under posterior lens capsule
- "orange peel, honey comb appearance"
- due to aging, trauma, steroids, diabetes
- major decrease in vision


Describe what patients usually have PSC (Cupuliform), what ocular symptoms they will complain of, near/distance vision affected more and how it could be caused

- Younger patients
- You see glare or decreased vision from miosis
- Near vision affected more than distance
- Can caused by secondary trauma, steriods (i.e. treatment for uveitis), inflammation, diabetes, ionizing radiation


What nuclear changes cause nuclear cataracts?

(What do new lens fibers do you nucleus, how does UV radiation cause biochemical change, what happens to lens (hardness and color) over time?)

- New fibers out outer portion push fibers inward and compact hardened nucleus
- UV radiation leads to accumulation of chromophors and cause nuclear sclerosis
- Lens becomes harder and more yellow leads to loss of elasticitiy (presbyopia)


What are the signs of nuclear cataract?

(Sudden or progressive onset, Refraction, nucleus color, myopic/hyperopic shift?, what type of diplopia?)

- regular progression
- variable refraction, myopic shift, yellow nucleus (urochrome pigment)
- monocular diplopia


What is the difference between burescent and cataract nigra?

- Burnescent: brown opacity (advanced stage)
- Cataract nigra: black color catarct


Describe characteristics of nuclear cataracts

(how much yellowing?, slow or fast progression?, affects distance or near vision more?, what color do patients have difficulty discrimination, what is lenticular myopia?)

- Excessive yellowing = nuclear cataract
- Slow progression, affects distance > near
- poor discrimination of blue
- lenticular myopia: increased refraction index


What are the percentage grades of PSC (Grade 1-4)

% of capsular space
- Grade 1: 3%
- Grade 2: 30%
- Grade 3: 50%
- Grade 4: >50%


What are the percentage grades of Cortical Cataracts (Grade 1-4)

% of pupillary space
- Grade 1: 10%
- Grade 2: 10-50%
- Grade 3: 50-90%
- Grade 4: >90%


What are the percentage grades of nuclear Cataracts (Grade 1-4)

- Grade 1: Mild
- Grade 2: Moderate
- Grade 3: Pronounced
- Grade 4: Severe