Corneal Disease in Cats: Welfare and Treatment
Common Corneal Conditions
Cats are prone to several corneal conditions: feline corneal sequestrum (dark plaque of necrotic corneal tissue, most common in Persians and Himalayans), corneal ulceration (caused by trauma, feline herpesvirus, eyelid abnormalities), corneal oedema, symblepharon (adhesions between conjunctiva and cornea from herpesvirus), and eosinophilic keratitis (pink/white plaques on the cornea). Each causes varying degrees of pain and vision impairment.
Welfare Impact
Corneal disease causes significant pain: blepharospasm (squinting), epiphora (excessive tearing), photophobia, pawing at the eye, and reluctance to open the eye are all signs of ocular discomfort. Corneal ulceration is acutely painful. Deep ulcers risk corneal perforation, which is a welfare emergency. Chronic conditions cause persistent low-grade pain and progressive vision loss, compromising quality of life.
Feline Herpesvirus and Corneal Welfare
Feline herpesvirus type 1 (FHV-1) is a common cause of corneal and conjunctival disease. It causes corneal ulceration (dendritic ulcers), corneal stromal disease, and symblepharon. Stress triggers recrudescence of latent virus. Antiviral treatment (topical cidofovir, oral famciclovir) reduces shedding and severity. L-lysine supplementation has shown inconsistent benefit; current evidence does not support routine use.
Corneal Sequestrum Management
Feline corneal sequestrum requires surgical keratectomy (removal of the necrotic plaque) to resolve. Medical management with lubricants and topical ciclosporin slows progression but does not cure. Post-operative pain management and protection of the surgical site (Elizabethan collar, soft contact lens) are essential. Recurrence is possible; brachycephalic cats with prominent globes require ongoing monitoring.
Owner Management and Prevention
Prompt veterinary attention for any signs of eye pain prevents complications. Maintaining FHV-1 vaccination, minimising stress, and supporting immune health reduces herpesvirus recrudescence. Regular eye cleaning in brachycephalic breeds prevents secondary infection. Eye lubricants for breeds with reduced blink rate reduce desiccation. Early treatment of eyelid abnormalities (entropion, distichiasis) prevents corneal damage.