Keeping it simple: An ophthalmologist’s approach to corneal ulcers

In this conversation taken from a recent episode of The Vet Blast Podcast presented by dvm360, our host Adam Christman, DVM, MBA, chatted with Kenneth Pierce, DVM, MS, DACVO, about what drew him to the specialty and how he approaches corneal ulcers in daily practice. Pierce shares his philosophy of keeping treatment focused on the essential, controlling infection, addressing inflammation, and identifying the underlying cause, and explains why photographs and well-timed recheck exams are among his most valuable tools.

This transcript has been edited lightly for clarity.

Adam Christman, DVM, MBA: I have to ask you, what made you become a veterinary ophthalmologist?

Kenneth Pierce, DVM, MS, DACVO: I knew going into vet school that I wanted to specialize, and initially I was between cardiology and neurology. At LSU at the time, the ophthalmology and neurology classes were actually combined, and so, having an interest in neurology and then this totally new language of ophthalmology and the entire disease process, I took to it immediately.

Then I started to consider the quality of life as ophthalmologists, the variety of species that we deal with, and the medicine and microsurgery that is done, so I was like, oh yeah, this is where I want to be. I also pursued networking opportunities, externships, and things like that with other ophthalmologists, and that just further solidified the deal.

Christman: What are the main therapeutic categories that a clinician should consider when treating corneal ulcers?

Pierce: Yeah, so I try to keep everything simple, right? Because, again, you’re dealing with a lot on a daily basis, so let’s keep it strictly to what’s 100% necessary. Typically there’s an infection going on, or we at least assume that there is. If not, sometimes it’s just the immune system that is overactive, so there’s an inflammatory component with every ulcer, and then there’s addressing whatever the underlying cause was.

So, your antibiotics: obviously, if you’re seeing white to yellow material within the corneal stroma, that’s screaming, “Hey, let’s get a sample of that.” Get a cytology, see what’s there, see if they’re rods or cocci, or in some cases there’s even fungus—which is rare in our small animal patients, but if you’re looking at horses, there’s definitely fungus among us all the time.

If you’ve got tons of neutrophils there, that is screaming this cornea is wickedly inflamed. It may even be on the potential scale of starting to melt. So get that sample; don’t be afraid to numb the cornea and touch it with a cytology brush, a cotton swab, or the back of a scalpel blade. Get that information, don’t lose that opportunity to learn more, and that will help steer your antibiotic of choice.

The other aspect is that sometimes you might need 2 different antibiotics. You may need to hit it from multiple spectrums. It’s not uncommon that they could have multiple organisms in a corneal ulcer, so don’t be afraid sometimes to have a second antibiotic—something that also gives you some properties that the first one doesn’t. For example, Terramycin: not only is it an antibiotic, but it also has some anticollagenase properties, so it will help with melting. Or we like to use Terramycin with our indolent ulcers, because it also has properties to improve the epithelial adhesion to the corneal stroma in those types of ulcers.

Anti-inflammatories—this is one of my soapboxes. In the literature, there are a few reports of topical non-steroidals potentiating a melting situation or delaying wound healing. There’s a camp of ophthalmologists where NSAIDs are all good and never an issue, and then there are others that swear by never putting an NSAID on a corneal ulcer. I would tell you, I’m in that first camp. There’s not an ulcer that I see and treat that does not leave without a topical NSAID, and that is because I know there’s inflammation there and that’s anti-inflammatory. The patients that I’ve seen—and that others have witnessed—that have gone home without a topical NSAID are significantly uncomfortable. Even if they’ve been on an oral pain medication or anti-inflammatory, you give them a drop of the topical NSAID, and the next day they’ll be so much more comfortable and have that eye so much more open. And I, knock on wood, have yet to have one that was melting because of an NSAID by itself, or where that was the culprit, as well as the delayed wound healing. I think from a clinical standpoint, it’s not as big of a deal as it makes it out to be from a research standpoint—the petri dishes and cell migration. Yeah, it may slow it down, but you’ve also got other factors in there that are also preventing the ulcer from healing. The other thing is to also titrate the frequencies.

And then, obviously, the last thing, like I mentioned, is addressing the underlying cause. Sometimes it’s hard to decipher from the owner’s history what may have caused the ulcer in the first place. So a lot of it may rely on just your thorough ophthalmic exam, where you may find KCS is huge, or an eyelid or contact to the cornea, whether it’s a mechanical irritation or something as a problem. So I would go on a hunt, spend that time, and really try to address it. And if you don’t know, then implement what may be important, right? Additional lubricant, some other form of pain management, or just treat the ulcer and then reassess once it’s all healed. Don’t just treat the ulcer and then see that patient 6 months later, after it’s healed up in 2 weeks. See them 2 to 3 weeks later, when everything is back to normal, and see what’s going on—if that underlying problem is still there or not.

Christman: Yeah, really helpful. I was always a picture kind of guy—I would have one on my phone—because sometimes I feel like some pet owners would feel like it’s not getting better, but then to me I was like, oh, it looks better. I have to go back to my phone just to see what it looked like initially, because sometimes they can go south quickly, as you know, right?

Pierce: Yeah, very much so. And pictures—that’s a good point. Pictures are worth 1000 words. I would even, on your normal wellness exam or whatever, get a picture of the eyes, right? Because that’s good reference information for you when that eye comes back and it’s bad, right?

Want to hear the full episode? You can check it out here, or wherever you listen to podcasts. There is also a new episode of The Vet Blast Podcast presented by dvm360 every Tuesday at 5 PM EST.