Questions to ask regarding the equine eye
•DO NOT trim lid margin
•May need to delay surgery
•Cover eye/wound with pad covered in antibiotic cream
•Careful debridement if necessary, then suture
•Eyelid margins have a very important role - specialised tissue
•DO NOT REMOVE EYELID MARGIN
•Use appropriate suture material - 4/0-6/0 Nylon
* Purulent discharge
* Check under third eyelid
* May need ocular ultrasound
* Surgery common
Treatment: may need ocular ultrasound, surgery common- GA, exploration of any sinus tracts, antibiotics, anti-inflammatories
What will you see in corneal disease in horses? (most common ocular disease)
* oedema, vascularisation, scarring, pigmentation, cellular infiltration, other abnormal infiltrates
Tests? What can occur with this?
* Tests: corneal cytology, MC&S, fluorescein stain, wash stain from conjunctival sac, do not confuse stain uptake in corneal granulation
* Corneal ulceration--> melting cornea chemotaxis for neutrophils, neutrophils important in melting corneas, not all ulcers are infected... caused by Pseudomonas, Staphs, Strep, Fungi (more common in horses, rare in dogs)...
- you would see: usually stromal loss, toxins and enzymes released by bacteria
Treatment: topical antibiotics/antifungals, consider compounded oral antifungal medication, serum topically...surgery- keratectomy/ conjunctival graft, consider transpalpebral lavage tube, pain control important- Bute twice daily
•Use dedicated topical ophthalmic antibiotics eg. Ofloxacin - Gram negatives
•Can use fortified drops eg. fortified cefazolin (50mg/ml - add 750 mg cefazolin to 12 ml artificial tears) - Gram positives
•Fungal infections in cornea most common in horses
•Use in horses with unresponsive chronic keratitis
•Topical - Voriconazole 1% drops or itraconazole 1% ointment (compounded), fluconazole (Diflucan), silver sulfadiazine (Silvazine), miconazole
•Oral - fluconazole (compounded)
What will you see with corneal infection?
From a corneal ulcer in a horse, what is the likely bacterial spp?
From corneal ulcer in a horse
Used after keratectomy/ conjunctival graft
Describe what you see
•Most corneal lacerations need surgery - suture cornea
•Need suitable instruments, suture material
•Replace iris prolapse as suturing
•Fencing wire, tree branch laceration
•If a corneal laceration is suspected, examine very carefully to prevent expulsion of intraocular contents
•Prognosis poor if laceration extends into the sclera
Uveitis in horses? Two kinds? Acute signs?
Primary- equine recurrent uveitis
Secondary- to other ocular diseases such as trauma and ulcer
** Acute signs: blepharospasm, corneal vascularisation, photophobia, miosis, aqueous flare and/or hypopyon
Tests? DDX? Diagnosis? Treatment?
Tests: Fluorescein stain, cytology, MC&S
DDX: trauma- whip/lead injuries, corneal infection, corneal ulceration
Diagnosis: Bullous keratopathy (horses cornea sucks in a lot of fluid)
- trauma- usually whip/lead injuries; corneal infection
DDX: Trauma, corneal oedema/infection, hypopyon
Tests: Fluorescein stain, tonometry
Diagnosis: acute uveitis (uncommon)... primary or secondary?
Treatment: treat primary cause, timely anti-inflammatory therapy- corticosteroids, NSAIDs, other immune modulating agents; atropine, poor treatment- loss of vision
* Adhesions- synechia; Darkened iris; cloudy pupil- cataract
Diagnosis? What are the signs and symptoms?
Chronic Uveitis (phthisis bulbi, cataract formation, posterior synechia, retinal detachment (ocular ultrasound), hyperpigmented iris, vitreous opacity, lens luxation, glaucoma)
What type of medication should you avoid in a corneal ulceration?