Non-healing (‘indolent’) cornealulcers
in dogs
The cornea is the transparent structure at the front of the eye that allows light to enter. Traumatic injury, most commonly a scratch, can damage the cornea and lead to corneal ulceration.

What is a corneal ulcer?
The surface of the cornea is covered by a thin layer called the epithelium, which protects the cornea and keeps it waterproof (see diagram below). An ulcer develops when part of this epithelium becomes scratched, exposing the underlying tissue. The eye becomes painful and cloudy, and the white of the eye may become reddened and inflamed.

The majority of corneal ulcers will heal rapidly within a few days, as the epithelium regenerates from the edges of the ulcer and spreads across the defect. However, in some dogs this healing process does not occur and they go on to develop an ‘indolent’ corneal ulcer. This type of corneal ulcer is shallow and non-infected but simply refuses to heal.

Indolent ulcers are usually quite uncomfortable and if left untreated they can persist for many months causing continuous irritation.

Treatment options for indolent ulceration include the following:

• Debridement. This involves gently rubbing away the loose epithelium from the surface of the cornea using a cotton bud, and is performed before one of the following two treatments:

• Keratotomy. Using a small needle, scratches are made on the surface of the cornea to allow the epithelium to spread across and ‘stick down’.

• Chemical cautery. Alternatively, chemical agents are used to carefully cauterise the surface of the ulcer to encourage healing.

There is a 60-70% likelihood that an ulcer will heal following the above treatment. If it does not work, it can be repeated every 2-3 weeks until the ulcer heals.

The eye may be a little more uncomfortable and cloudy after debridement and keratotomy, but this should settle over a few days.

Rarely the eye may become very inflamed and reddened. If you are concerned in any way (especially if a severe discharge develops, or if the eye appears very painful) then please give us a call for advice or to arrange a check-up examination.

What if the indolent ulcer does not heal?
On occasion an indolent ulcer will not heal despite repeated treatment. In such cases we can perform an operation called a superficial keratectomy. This has a 95% success rate. However it is not usually a ‘first-line’ treatment because it requires a general anaesthetic and can cause more scarring of the cornea than the above procedures.