Nonulcerative Keratopathies Flashcards
What is the general term for lesions that affect or involve the cornea that are NOT primarily ulcerative in nature. In these the overlying epithelium in intact.
Nonulcerative keratopathies
When assessing a corneal foreign body what are two characteristics that may determine if you refer the patient?
Depth and if the foreign body is penetrating into the cornea (if not superficial refer for sx removal and repair)
What type of foreign body has a higher risk of leading to infection?
Organic material (think about fungus)
Once you remove a corneal foreign body (flush it out), how would you treat?
Treat as ulcerative keratitis (topical abx, mydriatic, serum or EDTA, +/- systemic anti-inflammatories for pain)
What type of trauma is keratouveitis typically secondary to?
BLUNT trauma
What clinical sign is associated with damage to the endothelium?
Corneal edema!
What are treatment recommendations for post-traumatic keratouveitis?
Systemic NSAIDs, Topical steroids or NSAIDs (since corneal epithelium should be intact), + atropine (mydriatic).
Treatment is often in excess of 5 to 10 weeks. All edema usually dissipates at 6 to 8 weeks.
What would be the general diagnosis of an intact cornea with signs of inflammation (CORNEA ONLY)?
Nonulcerative keratitis (kera- cornea; itis- inflammation).
Can further classify these by location (ex: endothelial inflammation = endotheliitis)
What are the two traumatic or exposure etiologies for superficial keratitis?
KCS (uncommon), Facial nerve paralysis
What are the two common INFECTIOUS causes for superficial keratitis?
Viral or fungal
What is the viral agent(s) that is commonly associated with viral superficial keratitis in horses?
EHV-2 or 5
How would you treat a keratomycosis (fungal superficial keratitis)?
Treat as fungal ulcer for 4 to 6 weeks minimum (these are early fungal infections of the cornea that may be fluorescein negative)
A 8 year old QH mare presents to your clinic with a seed pod lodged in her cornea. You assess the depth of the foreign body and determine that it is superficial enough to flush off. After removal, what is this mare at high risk of developing?
Fungal infection (this is organic material and predisposes to infection).
What is the typical location for an eosinophilic keratitis lesion?
Peripheral cornea
A 6 year old QH gelding presents with signs of ocular discomfort (specifically blepharospasm). On your ophthalmic exam you note mucoid discharge, chemosis, conjunctival hyperemia, and white necrotic plaques that seem to originate from the peripheral cornea, and the patient is fluorescein negative, what would be your BEST differential diagnosis?
Eosinophilic keratitis
A 6 year old QH gelding presents with signs of ocular discomfort (specifically blepharospasm). On your ophthalmic exam you note mucoid discharge, chemosis, conjunctival hyperemia, and white necrotic plaques that seem to originate from the peripheral cornea, and the patient is fluorescein negative. You suspect that he has eosinophilic keratitis, what additional diagnostics would you want to perform in this case? and what would you expect to see if your suspicions are correct?
Cytology = inflammatory cells with eosinophils!
What is the recommended treatment for eosinophilic keratitis?
Topical abx + topical corticosteroids or topical immunomodulators (this is immune-mediated, so you need to modulate the immune response)!
Examples of immunomodulators = cyclosporine and tacrolimus
Can also place patient on systemic NSAIDs and mast cell stabilizing drugs (less commonly used)
A 3 year old TB gelding that frequently competes on the track presents to your clinic with branching superficial vessels, patchy edema, and cloudy, punctate corneal lesions. He is fluorescein negative, but rose bengal positive, what is the BEST differential diagnosis for this patient?
Herpetic keratitis
A 3 year old TB gelding that does not travel and lives on a small pasture presents to your clinic with prominent branching superficial vessels and patchy edema. The apposing conjunctiva also appears moderately hyperemic. He is fluorescein and rose bengal negative. The owner notes that the changes have progressed gradually over the last few weeks, what is the BEST differential diagnosis for this patient?
Superficial immune-mediated keratitis
How would you treat a superficial immune-mediated keratitis?
Treat with topical corticosteroid and/or cyclosporine (CsA). Taper steroids after resolution and continue with cyclosporine to prevent recurrence.
If medical therapy alone doesn’t keep the horse comfortable, consider a superficial keratectomy to prevent recurrence.
What parasite can cause a stromal keratitis?
Onchocerca
How would you treat a stromal immune-mediated keratitis?
Treat using CsA because corticosteroid response is poor and is less responsive that superficial IMMK.
