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
http://davidlwilliams.org.uk/
www.cliniciansbrief.com