Feline Corneal Ulcers

Feline Herpesvirus Keratitis
This is the most common cause of feline corneal ulcers. Types include geographic and dendritic. Geographic are superficial with loose epithelium at the edges. Their appearance is identical to indolent corneal ulcers in dogs. Dendritic ulcers are pinpoint to linear branching ulcers. There may or may not be blood vessels present in the cornea. These eyes frequently develop corneal sequestra thus should be monitored closely for signs of discolouration.

Treatment regimes can vary but at Animal Eye Care we use:
- Cidofovir drops twice daily (although currently unavailable) for 1-2 weeks
- Doxycycline 2-5mg/kg BID
- Oral lysine 500mg BID reducing to SID when ulcer healed for 2-3 weeks
As Cidofovir is not available at present we are using:
- Oral famcyclovir 250mg BID (40mg/kg TID or 60mg/kg BID)
- Doxycycline and lysine as above
We will also use oral meloxicam for painful eyes and often Luxyal tears as required for lubrication. Interferon in tears is used for early cases of discolouration however many cases develop sequestra and require surgery.

For cases that fail to heal, superficial keratectomy can be performed. Under no circumstances should a grid keratotomy every be performed on a cat.

Trauma induced ulcers
Routine treatment of non-complicated ulcers in cats includes:
- topical Chloromycetin drops or Conoptal ointment
- oral doxycycline 2-5mg/kg BID
- oral meloxicam SID
- atropine ointment SID as required depending on uveitis

In cases of infected corneal ulcers we would use topical ofloxacin (Ocuflox) drops 10 times daily initially reducing as infection is controlled, plus Conoptal, doxycycline, meloxicam and atropine.

Exposure keratitis
It is possible for glaucomatous eyes that are enlarged to develop exposure keratitis with ulceration. Removal of enlarged cats’ eyes is considered a referral surgery due to complication rates.

Trigeminal nerve deficit
Cats can develop vascular keratitis and an oval shaped ulcer on the lateral axial cornea associated with loss of corneal sensation. Sensation can be tested for by touching the cornea with fine wisps of cotton wool. These cases would be treated as above and monitored closely with the addition of more lubricating ointments such as Tricin (if tolerated) or Lacrilube. If the corneal sensation does not return, permanent partial lateral canthal closure may be performed.