Debridement Of Canine And Feline Corneal Ulcers

This is Sara.

Well, more specifically, this is Sara’s right eye.

Sara’s first visit with this eye problem was about a week ago, and she presented with a history of squinting and protecting the eye.

We examined Sara thoroughly, and found no other physical problems on the body, so we turned our focus to the eye. Instillation of fluorescein stain showed a large area of the cornea was damaged. The shape of the lesion was consistent with a scrape that may have come from “sister” Lil’ Catherine, from running into a stick, or any number of other possible causes of corneal trauma.

We began symptomatic therapy, treating with an antibiotic to ensure the ulcer didn’t become infected, and with oral and topical pain medication. Corneal ulcer is known, from experience of people, to be the second most painful injury we can experience, second only to passing a kidney stone.

At our first evaluation a week later we discovered that there was little healing, although it seemed that Sara didn’t squint as much as the previous week.

At that time we added a treatment called autogenous serum, also called autologous serum. This form of treatment is relatively easy to make right in our own hospital’s lab. We draw blood, abour four times as much as one might need for a chemistry profile. The blood is allowed to clot, then it is centrifuged to separate the blood cells from the blood liquid, called serum. The serum is collected into a vial that can be used to dispense drops into the eye 3-4 times daily. Often the healing effect made from one’s own body can be dramatic.

After an additional week of treatment Sara’s cornea looks better, but still hasn’t healed completely. In fact, it seems to have reached a certain point of healing, then stopped. This is typical behavior for an indolent ulcer, one that tries to heal, but simply cannot reach complete healing.

The best and most modern next step for lesions such as Sara’s is to create a crosshatch on the cornea. To accomplish that, the patient goes under general anesthesia, the eyelids are propped open with a speculum to allow easy and full access to the cornea, and a small, sharp instrument is used to make tiny, shallow incisions across the entire cornea, incorporating the lesion. The process is believed to simply “tell” the body that there is something going on in the eye that needs immediate healing attention, for it to get off its duff and get back to healing, just as it should any incision or laceration.

Today, however, we used an older technique that has proven itself very successful over a number of decades. It doesn’t require general anesthesia, just topical anesthesia on the eye itself, and a little sedation. Some dogs will even tolerate this procedure without sedation.

With some ophthalmic anesthetic on the cornea, and some applied to a sterile surgical sponge, the lesion and a little area around it are “scrubbed” gently. The effect is very similar to the crosshatching treatment above, in that defensive and healing mechanisms are activated, and the sluggish healing is then speeded up.

Sara had a very successful procedure today, as we saw a substantial amount of unattached corneal tissue appear on our surgical sponge.

We will evaluate Sara’s healing again in three days, and anticipate a rapid recovery.

See you tomorrow, Dr. Randolph.