A simple, systematic approach to canine corneal

ulcersAllyson D. Groth

BVSc(hons), MANZCVS, DACVOSpecialist in Veterinary Ophthalmology

Diagnosis Classification What’s known What to do Cases

Outline

Pain Redness Discharge Cloudiness

Diagnosis: Symptoms

Topical anaesthetic always OK – exam ONLY Corneal defect Fluorescein stain retention** Miosis Anterior chamber reaction

** Care with descemetoceles & “indolent” ulcers

Diagnosis: Examination

Classification

Uncomplicated Complicated

History◦ <7 days duration

No vascularisation No change in stromal character:

◦ No malacia◦ No cellular infiltrate◦ No stromal loss (divot)

Uncomplicated

Prophylactic antibiotics TID◦ Chloropt, Opticin, Tricin

Atropine (q24-72h) Oral NSAIDs NO topical steroids or NSAIDs E-collar

Monitor for deterioration q3-5 days

Continue until healed or “complicated”

Uncomplicated

Classification

Uncomplicated Complicated

Complicated

Signalment: brachycephalic History: previous medications, ocular

disease/surgery Change in stromal character:

◦ Malacia◦ Loss (depth/divot)◦ Cellular infiltrate – colour change

Anterior chamber reaction

Infection

Cytology predicted culture result in 50/71 cases (70%)

19%: -ve cytology, +ve culture 11%: +ve cytology (PMN’s or bacteria), -ve

culture

Infection

β-Hemolytic Streptococcus spp:◦ 14/45, 31%◦ Resistant to neomycin, polymyxin B, gentamicin,

framycetin & fusidic acid◦ >80% resistant to ciprofloxacin ◦ Susceptible to chloramphenicol & cephalexin

Pseudomonas aeruginosa: ◦ 14/45, 31%◦ Resistant to chloramphenicol, cephalexin, and fusidic

acid◦ >90% susceptible to ciprofloxacin, polymyxin B &

gentamicin

Infection

Pseudomonas aeruginosa: ◦ 14/45, 31%◦ Resistant to chloramphenicol, cephalexin, and

fusidic acid◦ >90% susceptible to ciprofloxacin, polymyxin B &

gentamicin Staphylococcus spp:

◦ 8/45, 18%◦ Susceptible to chloramphenicol, fusidic acid,

gentamicin, ciprofloxacin

Infection

23.9% Staph spp methicillin resistant 23.5% dogs with MRS corneal isolates had +ve MRS nasal

cultures Client occupation significantly (P = 0.01) associated with

MRS isolation Dogs belonging to owners employed in veterinary or human

healthcare fields 4X more likely to have MRS keratitis

Infection

Best: 26/37 (70%) isolates susceptible to ciprofloxacin◦ NOT alone for Strep spp.◦ Good combined with chloramphenicol for Strep

spp. Worse: 5/36 (14%) isolates susceptible to

fusidic acid

Infection

Hospitalize for aggressive medical therapy: topical AB’s, atropine, NSAIDs, serum

Surgery indicated if >50% stromal loss – obvious divot◦ Referral for corneal/conjunctival/biomaterial graft

TEL flap generally no use/counterproductive Monitor closely

Infection

Complicated

Foreign body - acute Trichiasis

◦ Entropion: primary/conformational, secondary/spastic◦ Periocular, nasal fold◦ Distichia, ectopic cilia – young dogs

Ongoing irritation

Qualitative/quantitative tear film deficiency◦ Immune-mediated, neurogenic (nose), toxic/drugs

Exposure: conformational, neuropathy Degeneration: usually calcium, geriatric Excessively frequent debridement Topical epithelial toxicity – medications

Ongoing irritation

Complicated

Spontaneous Chronic Corneal Epithelial Defects (SCCED)

>7-10 days *ALWAYS superficial* *NEVER stromal change*

◦ Malacia◦ Loss (thinning)◦ Infiltrate

Boxers, all ages Middle-aged/older dogs, any breed +/- oedema +/- vascularisation (chronicity, ~50% cases)

“Indolent”

Cotton bud debridement: ~50% healed Grid/multifocal punctate keratotomy: ~80% healed Superficial keratectomy: 100% healed

95% BCL retention (Acrivet, 2 sizes) >90% healed by ~2 weeks 100% healed within 19 days Second tx in 12.5% cases Suspected bacterial infection in 1 case

Uncomplicated Complicated

Prophylactic antibiotics TID Atropine (q24-72h) Oral NSAIDs NO topical steroids or NSAIDs E-collar

Monitor for deterioration q3-5 days

Continue until healed or “complicated”

Uncomplicated Complicated

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