Cataracts Flashcards
(23 cards)
What is the normal function of the lens or the eye?
Focus light onto the retina, adjust focus for objects close or far away – provides clear vision
What is the lends made of?
Water and proteins, arranged in a way that keeps lens clear and lets light pass through
What are cataracts?
Clouding of the crystalline lens
– crystalline proteins clump together and start to cloud a small area; can grow and obstruct more vision
What is a subcapsular cataract?
Who is at greater risk of developing one?
Occurs at back of the lens
Diabetes and steroid medications are at higher risk
What is a nuclear cataract?
What is it associated with?
Forms deep in the central zone.
Associated with aging
What is a cortical cataract?
Characterized by white, wedge-like opacities that start in the periphery of the lens and work their way to the center in a spoke-like fashion.
What are the causes associated with cataracts?
Aging (most common) Prolonged corticosteroid use Statins Phenothiazines Inflammation Trauma Radiation exposure Systemic disease (diabetes, Wilson's
What are the clinical symptoms of cataracts?
Reduced vision
Glare while driving during day, and at night with headlights
Dulling colors
Double images
What are the 4 pre-op eye drops used, and what are their functions?
Diclofenac 0.1%: anti-inflammatory
Tropicamide 1%: Mydriatc-cyclopegic
Cyclopentolate 0.5-2%: Mydriatic-cycloplegic
Phenylephrine 2.5%: Mydriatic
What are the 3 classes pf post-op care medications?
Antibiotic (moxiflox, cipro, gatifloxacin) QIDx1wk
NSAID (diclofenac, ketorolac): QIDx1wk
Corticosteroid (prednisoone): QIDx1wk then BIDx2wks
What is extracapsular surgery?
Remove the lens from the capsule
What is phacoemulsification?
Probe into lens through capsule, high frequency top dissolves lens
What is intracapsular surgery?
Remove whole capsule and lens; lens put in front of iris
What are the 3 post-op complications?
Uveitis
Infectious endophthalmitis
Post-op intraocular pressure spikes
What is uveitis?
When is it not typical?
Some inflammation in the anterior chamber is expected
Persistent inflammation past 4 weeks or unusual severity early post-op is not typical
What are the causes of uveitis?
Infectious endophthalmitis Phacoanaphylaxis Abrupt taper to steroids Patient non-adherent to steroid drops Pre-existing uveitis Use of prostaglandin hypotensive drops
What is infectious endophthalmitis?
Most serious and feared complication - can quickly and irreversibly devastate vision.
Incidence <0.1%
Can present first few days post-op, or delayed onset - weeks or years.
How does infectious endophthalmitis present?
Worsening redness
Pain
Photosensitivity
Decreasing vision
What is used to treat infectious endophthalmitis?
IV:
Vanco
Ceftazidime
Drop (after IV):
Moxifloxacin (Q1H)
Prednisolone (Q1H)
Homatropine (BID)
What are the signs of post-op intraocular pressure spikes?
Redness Pain Photophobia IOP > 35 mmHg N/V
What are the drug of choice for post-op IOP spikes?
What drugs should be avoided?
Beta blockers - drug of choice
Avoid prostaglandins
What is the most common complication following cataract surgery?
what is the treatment?
Posterior capsule opacification (risk increases with time after surgery)
Treatment: YAG capsulotomy - create hole in posterior opaque membrane
What is crucial to having success after cataract surgery?
Patient adherence to eye drop instructions
