CORNEAL DEGENERATIONS Flashcards
(26 cards)
what are corneal degenerations?
- Gradual deterioration in the tissue of the cornea into a less functional form.
- Non-hereditary conditions that occur secondary to aging, previous insult, or disease.
- Show as unilateral, asymetrical & mainly affects the peripheral cornea & vessels (neovascular)
what are symptoms of corneal degenerations?
- asymptomatic, but can have: pain, photophobia, epiphora, blurry vision.
what is Corneal arcus (arcus senilis)
Lipid deposition begins on Descemet’s membrane and Bowman’s layer before extending into the stroma.
what is arcus associated with?
- Associated with aging and high cholesterol
signs of arcus?
- appears as a white, hazy band in the superior & inferior margins of the cornea –> then extends 360 degrees around the peripheral cornea.
what to do if patient is less than 40 years old with arcus?
lipid panel is required
what is limbal girdle of Vogt?
- Deposition composed of fine granular chalk-like flecks underneath the corneal epithelium.
signs of limbal girdle of Vogt?
- Yellowish-white, chalky, arc-like band located 3 & 9 o’clock of the intrapalpebral limbus.
what is Crocodile shagreen?
- Crocodile shagreen is characterized by bilateral greyish– white cracked ice/mosaic pattern in Bowman’s layer.
what is Cornea farinata?
- Characterized by fine flour-like deposits (flour dust) in the central deep stroma
what is band keratopathy?
- Band keratopathy consists of the age-related deposition of calcium salts or uric crystal in Bowmans layer, epithelial basement membrane and anterior stroma.
what systemic conditions can band keratopathy be associated with?
- calcium salts = hypercalcemia
- uric crystals = gout
signs of band keratopathy?
- Peripheral interpalpebral calcification with gradual central spread to form a band-like chalky plaque containing transparent small holes that gives a “Swiss cheese” appearance
tx for band keratopathy?
aimed at removing calcium via:
* * Chelation via EDTA (dissolves calcium).
* superficial keratectomy
* phototherapeutic keratectomy (PTK)
what is Salzmann’s nodular?
- Raised, blue/gray-white hyaline plaques (nodules) arranged in circular fashion around the corneal mid-periphery at the layer of Bowman’s membrane
what causes Salzmann’s nodular degeneration?
- caused by chronic corneal inflammation (inflammatory disease)
tx for salzmann’s nodular degeneration?
aimed at removing nodules via:
* superficial keratectomy
* phototherapeutic keratectomy (PTK)
what is lipid keratopathy?
- Fatty degeneration of the cornea characterized by whitish-yellowish deposits consisting of cholesterol & fatty acids.
what are the 2 types of lipid keratopathy?
- Primary – lipid degeneration occurs in the absence of corneal vascularization & serum lipid levels are normal.
- Secondary – lipid degeneration occurs with corneal vascularization secondary to disease such as corneal infections (HSV/HZV), interstitial keratitis, ocular trauma, glaucoma, chronic iridocyclitis.
tx for lipid keratopathy?
aimed at reducing inflammation via:
* argon laser photogoagulation
* Topical corticosteroids
* Needle point cautery
* PK
what is Terrien marginal degeneration
painless, bilateral, slow progressive peripheral corneal thinning w/ fine superficial vascularization
Terrien marginal degeneration occurs in what quadrant of the cornea?
- superior cornea
what kind of astigmatism can Terrien marginal degeneration lead to?
ATR
who gets terrien marginal degeneration
men in their 30s