Page 1241 - Problem-Based Feline Medicine

60. The cat with abnormalities confined

to the cornea

Richard IE Smith

KEY SIGNS
● Cloudy cornea.
● Redness from vascularization.
● Pink or white plaque.
● Coffee to black staining lesion.
● Ocular pain (blepharospasm, photophobia).

MECHANISM?
● Superficial damage to the epithelial surface causes an erosion (superficial ulcer). Loss of
epithelium and stromal tissue results in a deep ulcer with a loss of transparency of the cornea
because of edema of the stromal tissue.
● Cats with uveitis secondary to systemic disease may show changes in the inner endothelial cell
layer. This will be seen as corneal edema (diffuse grayish appearance) and there may be “ker-
atic precipitates” (focal deposits consisting of white blood cells and fibrin) present on the
endothelium.
● The cat has some unique degenerative and immune-mediated corneal diseases.

WHERE?
● Cornea (epithelium, stroma, endothelium).
WHAT?
● Trauma and infectious diseases affecting the upper respiratory system are the main causes of
corneal disease in cats.
● The cat cornea develops a unique degenerative disease, which forms a corneal sequestrum.
● An immune-mediated disease called eosinophylic keratitis is seen associated with allergic
states.
● Corneal edema and keratitic precipitates are seen in cats with uveitis, usually secondary to
systemic disease.

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