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Corneal Ulceration 211

Recommended Monitoring
• Evaluate for epithelialization (healing) or
VetBooks.ir • Repeat corneal cytologic evaluation and/or Diseases and Disorders
progressive loss of corneal stromal layers.
culture to monitor response to antimicrobial
therapy, especially if progressive stromal loss
occurs despite current therapies.
• STT: repeat after ulcer is healed to rule out
KCS as initiating cause.

PROGNOSIS & OUTCOME
A • Simple: most heal with minimal scarring
within 5-10 days with appropriate treatment.
• Indolent: most heal with minimal scarring
within 2-3 weeks with appropriate treatment.
• Complex: healing may take 2-8 weeks, and
substantial corneal scarring is expected.
PEARLS & CONSIDERATIONS

Comments
• Topical corticosteroids are contraindicated
B with ulceration; they delay healing and
promote infection and keratomalacia/
melting.
• Referral to a veterinary ophthalmologist is
recommended if ulcer progresses despite
appropriate medical management and/or
if ulcer exceeds 50% stromal depth or is
ruptured because surgical repair is usually
required.
• Any simple corneal ulcer that does not heal
in 5-10 days should be considered a complex
C or indolent/refractory ulcer, and underlying
causes such as infection, foreign body, ectopic
CORNEAL ULCERATION Grid keratotomy. A, Indolent ulcer with corneal epithelial flaps (at time of presenta- cilia, and distichia must be ruled out.
tion). B, After topical anesthesia and debridement. C, Performing the grid keratotomy.
Prevention
Avoid or treat underlying cause(s).
• Debridement of all loose corneal epithelium • ± Systemic NSAID (e.g., carprofen)
with dry, sterile, cotton-tipped applicators • ± Application of a bandage soft contact lens Technician Tips
• Perform one of the following procedures to to improve comfort and minimize mechani- To prevent rupture or expulsion of aqueous
promote epithelialization cal forces of eyelids on migrating corneal humor due to increased intraocular pressure,
○ Grid keratotomy with the beveled edge epithelium avoid excessive restraint or jugular pressure in
of a 25-gauge needle held at a 45-degree • Placement of an Elizabethan collar to prevent patients diagnosed with a descemetocele or
angle (or tangential) to the cornea dog from rubbing eye corneal rupture.
Gentle vertical and horizontal scratches
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every 0.5 mm over ulcerated area just Chronic Treatment Client Education
into the normal epithelium and just • Treat underlying cause if present. • Simple corneal ulcers may become complex;
through basement membrane into • Adjust antimicrobial therapy as directed by topical antibiotic treatment and regular
superficial stroma (grid lines should culture and susceptibility results and/or lack follow-up to assess ulcer healing are crucial.
be barely visible) of improvement. • Indolent corneal ulcers may recur in the same
Contraindicated in cats (may predispose • Change to a topical antibiotic with expanded- eye or occur in the opposite eye.
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to sequestrum formation) spectrum and/or improved corneal penetra- • The patient’s eye is frequently more uncom-
○ Diamond burr (Algerbrush II) debride- tion (e.g., fluoroquinolone). fortable for 24-48 hours after epithelial
ment of the ulcerated area • FHV-1 ulcer: additional, specific antiviral debridement and multiple grid keratotomy
Use a fine or medium 2.5- or 3.5-mm treatments (p. 464); avoid topical neomycin or diamond burr debridement have been
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round polishing bur. in cats due to possible hypersensitivity. performed to treat an indolent corneal ulcer.
Apply very slight pressure with rotat- Erythromycin or oxytetracycline-polymyxin
■
ing bur using even, circular movement B (Terramycin) ointment is usually well SUGGESTED READING
across ulcer and normal epithelial tolerated. Maggs DJ: Cornea and sclera-corneal ulcers and
margins. erosions in all species. In Maggs DJ, et al, editors:
• Oxytetracycline/polymyxin B (Terramycin) Possible Complications Slatter’s Fundamentals of veterinary ophthalmology,
ointment (promotes corneal epithelialization) Corneal perforation, corneal scarring, corneal ed 5, St. Louis, 2013, Saunders, pp 195-211.
q 6-8h pigmentation, permanent corneal stromal defect AUTHOR: Anne J. Gemensky-Metzler, DVM, MS,
• Atropine 1% ophthalmic solution or oint- (i.e., facet), corneal sequestration (cats), vision DACVO
ment q 24-72h impairment/loss are possible. EDITOR: Diane V. H. Hendrix, DVM, DACVO

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