I frequently get asked “what is the most common problem you see?”. The long answer is “depends!” as different species get different diseases, different breeds get different problems, and some problems are seasonal and others are year round. So the allergic conjunctivitis may be absent in winter but cataracts occur at any time and at any age. But one of the problems that shows up on our doorstep on a regular basis is the non-healing corneal erosion in the dog. Your poor friend may be squinting and pawing for weeks in spite of repeated attempts to heal with various topical medications that don’t quite get it done. Well have no fear, we have lots of information and numerous options to get these frustrating lesions to heal.
First things first! The cornea is the clear windshield on the surface of the eye. Its clarity is maintained by a good amount of tears and, in mammals at least, the lids to protect it. It has a ton of nerve endings associated with it to alert us to the smallest particle or irritant so that healing can proceed at a rapid rate. And to maintain its function as the windshield of the eye, healing is optimal if the clarity is minimally affected at its conclusion.
Cross section of the human eye. The cornea is on the left.
This structure is a common location of concern for us since it is a frequently damaged or diseased layer with obvious importance to vision and comfort. In a geeky ophthalmologist way, this is my favorite tissue to assess and treat. And thankfully, there are a limited number of opacities that we can see on the cornea that relate to its diseased state. These opacities are grouped into a common lecture I give general practitioners to aid them in diagnosis. But I digress…it is the superficial corneal erosion that is our topic today.
Ulcers or erosions of the cornea come in different flavors, some superficial, some deep. Some are infected, others are not. Some are traumatic, many are not. However, a feature of healing of the superficial layer is the same. The surface tissue of these defects heal from side-to-side in a sliding and sticking process. And that process should occur in a few days in the proper environment. It is the inability of this sliding and sticking mechanism to work that is the root of the evil in many of these specific non-healing erosions.
There are many names for this entity. The Boxer was and is a common breed to experience these and thus were call Boxer Ulcers in the past. Other names include non-healing ulcers, indolent erosions and recurrent erosions. Recent nomenclature has gotten fancy calling this SCCEDS for spontaneous, chronic corneal epithelial defect syndrome. I prefer indolent erosions which will be used as we go on.
Indolent erosion. Notice the loose edges that are peeling back.
The three features of indolent erosions are as follows. First, they usually have to be present for up to 3 weeks in the first instance to determine it is an indolent. Secondly, no infection is present. Thirdly, only the superficial or epithelial layer is involved and is characterized by loose edges that easily debride or fall off when gently rubbed with a cotton-tipped applicator after placement of a topical anesthetic. A trauma is rarely seen and thus most are considered to be spontaneous rather than a traumatic lesion that does not heal. However, some clients do observe some initial event.
Now one thing to be clear! Not all ulcers or erosions with slow healing fit into this class of disease. Abnormal hairs directed on the cornea, ulcers that are deep due to the presence of bacteria or degenerative lesions from mineral in the cornea may be examples of problems that will progress in a similar but different manor. So before you tell your veterinarian to do A, B, or C, make sure the appropriate diagnosis is made!
So you have been treating Rex for 3 weeks with 4 different antibiotics, artificial tears, serum, clizabethan collar, Uncle Jimmy’s special blend, tea bags or whatever and still have not seen a complete resolution. Never fear, here is the mantra. This type of superficial erosion with loose edges +/- blood vessel response will always heal, rarely become infected and rarely get deep. So you can treat them until you are blue in the face with antibiotic and they won’t go away. The key is that we must mechanically address this inability of the surface tissue to slide and stick to effect a cure and there are multiple ways to achieve this.
The most common procedures you will see us do for this disease is a punctate, grid or burr keratotomy. In general, this is what happens. After placement of a topical anesthetic, the surface tissue is debrided with the cotton-tipped applicator until all non-adherent tissue comes off. This could be the entire cornea or just a local region. This is the first step to healing and a small percentage of dogs will heal with this process alone. Your veterinarian may be comfortable doing this or has already done it. (Again, not every ulcer should be debrided, especially if it is not just superficial!). Once that is done, the base tissue called the stroma is roughened up using a needle to poke small shallow holes or grid lines or a fancy tool called a corneal burr that spins to alter this base tissue. My analogy is like priming a wall before you paint it. This prepares this tissue for the new cells to now slide across and adhere in a normal fashion. Healing will occur within a 2 week period probably greater than 80% of time. In our hands, this can typically be done without anesthesia unless your dog won’t sit still or the erosion is in a location that is difficult to access.
Punctate keratotomy; immediately after treatment
Comfort is the key and if your dog seems 100% pain free at the recheck, it is more than likely healed. If they are better but not complete, you may be in the 20% and need more time, repeat keratotomy or additional manipulations that can be used to make these heal. Contact lenses and corneal glue are other treatments that can be employed. If the lesion is big, been there forever and you just want it to be gone, a surgery under general anesthesia call a keratectomy, where the abnormal surface is shaved off, will heal these 99.9% of the time. But if we can manage these without needing an anesthetic event, we usually try that first.
There’s lot more we could talk about with this common disease but can get even more esoteric than what I have already written. But if this sounds like your dog, there is a good chance that we can help you out! By the way, cats don’t get this disease and non-healing erosions would be treated differently….so much to learn! Stay warm!
I was stunned to see the last posted picture on the front page here had snow all over the building and I was talking about our wonderful warm environment that is present year round. Now the warmth of summer is waning and we are all holding on to those last few days with green trees and sunny skies. A beautiful summer was our just reward after such a harsh winter! And September was equally nice!
Our pets have survived as well, and do through many adverse conditions and illnesses that would knock us for a loop. We can learn a lot by observing how our pets roll with the punches with challenging conditions and disease. Graceful and honorable acceptance, if that is the right word, with a “how do I make it past this” attitude is prevalent in most of our patients. Here at the Animal Eye Clinic, we fortunately see mostly healthy patients with various injuries, diseases, or genetic failures that affect the eye’s function. Some are uncomfortable issues and many are not, while some affect function and just as many do not. Our goal in most cases is to achieve or preserve a comfortable and functional eye. Sometimes, a comfortable blind eye is the best we can do whether limited by disease, finances or age restrictions. But if we fail to maintain a comfortable and sighted eye through the process, that is when we talk about eye removal or some cosmetic choices that might be better looking but still maintain a comfortable globe.
The good news here is that losing an eye is usually much harder on us than it is to our pets. They may not be too worried about their appearance and just want to be free of whatever painful problem that is affecting their normal day-to-day activities. Glaucoma is the most common entity that leads to this discussion. This painful, blinding disease is manifest by headache pain that is obvious when acute but less so when chronic. This disease can warrant a few pages of conversation in itself, however, the point here is that your dog or cat may be uncomfortable and you won’t notice it until that pain is resolved. I can line clients up around the block that have returned once their dog’s glaucoma has resolved, usually by surgery, and are amazed that they have a new dog. “She hasn’t played with that in months” or “I thought he was just getting old” are common comments that people will voice after eye removal or prosthetic surgery.
Granted, making that decision is often times not as easy as it sounds on an emotional level. We are staring into our pet’s eyes on a regular basis and altering that expression often gives pause. However, if our goal is comfort and function is lost, we need to set those emotions aside to make the best choices for our friends. The indications for surgery in these cases are three in my hands: 1) a painful blind eye, 2) an eye that is blind but needs drug or surgery to keep it comfortable or 3) tumor. As with any procedure, we balance the dog’s needs with the practicalities of cost, postoperative care, need for rechecks, cosmetic concerns, anesthetic risk, etc. to help you make an informed decision. As long as the result is comfort, there is rarely a wrong choice.
One of the greatest benefits of removing the eye on a medical level is the pathology report we get on the removed eye. We send the globe to the Ocular Pathology Lab at the University of Wisconsin where they specialize in veterinary ocular disease. The results from this report will usually tell us the cause of the problem if unknown and, most importantly, if there is any risk to the remaining eye or spread to the body if tumor is suspected. In rare cases we also learn if systemic symptoms, if concurrent, are related to the eye. This information helps with long term prognosis and allows us to make specific recommendations for treatment if the other eye is at risk. That’s all good if we have achieved comfort as well as useful information for life after surgery.
With routine eye removal, or enucleation, the eye is removed in total along with the lid margins. In my hands, a silicone ball is placed in the socket to fill the space occupied prior by the globe. This minimizes the sinking-in look or indentation that can result once the surgical site has healed when an orbital implant is not placed. It also can act to compress the vessels and minimize the bleeding or accumulation of blood in the socket after surgery. I close the skin and deeper tissue in three layers and remove the external sutures in 10-14 days. They usually do great without the need of an Elizabethan collar after surgery. A little pain medication and antibiotic and they are feeling better in short order. The final appearance is that of a winking pet as shown above. Sometimes, especially in long-haired animals, you may not even be able to tell! Short-haired dogs and cats are a little more obvious that they have lost the eye.
Certainly there are instances when we know why eye removal is advised. Observed trauma, for example, can ultimately lead to glaucoma and thus the benefit of pathology may be minimal. It is in cases like these where cosmetic procedures are an option. In these instances, we are again striving for comfort but placing cosmetics as a priority as well. Two surgeries are available in veterinary ophthalmology in this instance; 1) intraocular prosthesis (ISP) or 2) chemical cycloablation for glaucoma.
With an ISP, and incision is made into the shell or sclera of the eyeball and the internal contents of the eye are removed and replaced with a smaller silicone ball than is used for enucleation. The difference is that this ball is placed within the shell of the eye and then closed over the surface. Thus, the eyeball still moves, winks and tears but all the machinery that has created the intraocular problem has been removed. The take home point here is that 1) we lose the benefit of accurate pathology to assess the drain since the architecture/anatomy of the eye has been changed and 2) surface disease can still occur. So if your pet has dry eye, you still have to treat it. Lid tumors, conjunctivitis, corneal scratches are all examples of problems that can occur since the healthy surface tissue remains behind. So if you have concurrent surface disease or intraocular tumor is a possibility, this procedure may not be the best choice. Tumor could be left behind or you may still be having to treat a prosthetic eye which may not be in your pet’s best interest. Different than humans, this is not a glass eye that is painted to match the remaining eye that you have to occasionally remove and clean. It is their eye, just one that is non-functional but comfortable after removal of the internal contents. Postoperative care requires a little more work than eye removal with topical and oral medications and use of an E. collar in the short term. However, this is a nice option if the cosmetics is important to you. Ginger above had an ISP in the right eye and she looks pretty good, no?!
Lastly, chemical cycloablation is a technique used for dogs with glaucoma where a drug is injected into the eye in attempts to decrease the pressure. The drug, usually an antibiotic, is toxic to the intraocular structures including the gland that produces the fluid that fills the eye. Thus, given time, the pressure in the eye will decrease as the production drops. The benefits are ease of the procedure, short duration of the procedure and costs associated as this can be done under a short acting anesthetic. The downside is that it is not 100% successful, the end result is less predictable and as with the ISP may be contraindicated with some diseases. I personally do less of these due to this lack of a definitive outcome. However, if cost is an issue or anesthesia is a risk, it is still a nice option in some cases.
As stated before, glaucoma by many causes is the primary reason we end up discussing these surgeries. And as difficult as the decision may seem, a successful result equals a happier pet. Those who have ultimately made this decision and, when seeing how happy their pet is without a migraine headache, wonder why they didn’t do it earlier. Yes, our pets will soldier on and mask signs of chronic discomfort to a point where we think they are fine. But in retrospect, it is amazing to see and hear the comments “He’s acting like a puppy or kitten again” to remind us how rewarding these surgeries can be.
Been cold enough for you out there? It sure has been for me. I like winter. I enjoy skiing, sledding with the kids, playing frisbee with my dog Tess after a fresh snow, the Winter Olympics this year. a warm fire, Christmas….but wait! I feel like it has been about 9 degrees all season long. Trust me, this is not a big complaint. I lived in Wisconsin for 7 years so this is nothing. And don’t get me started on snow days at school when it closes if it might snow! Alas, that’s one reason we live here is the
Continue reading A Warm Environment in the Cold Weather
This may be one of the more common cocktail party questions that veterinary ophthalmologists get asked! Not that eyes in any species are not cool, but a little exotic flavor can spice up the conversation. Fortunately for us veterinary ophthalmologists, the anatomy of the eye is very similar from species to species. There are significant changes when going from mammal to bird to fish since the anatomy is altered to maximize performance depending on the environment in which an animal lives, however, the main structures are present in most eyes. Disease states will also be different based on these living
Continue reading What is the coolest animal you have seen?
Welcome back from the holidays! Hope everyone had a wonderful season full of family joy and giving. Our family here at the Animal Eye Clinic had no complaints as apparently all were on the “nice” list and the New Year rang in sweetly. And now that we have weathered the latest series of storms, I guess it means back to work for all full time!
We had last started a discussion about lid disease. We see lots of patients here with a variety of lid maladies that affect its position, function and appearance. Some are genetic in origin, many are acquired
Continue reading Put Another Lid on It!
From all of us at the Animal Eye Clinic to all of you, may you have a very Merry Christmas, a Happy Hanukkah and a Happy New Year! May your travels be safe and family be healthy and happy. We all hope and pray that the new year will fill us with peace and prosperity after such a trying 2012 especially here in the Northeast. Many thanks to all who visit us here in Wilton as we try our best in our little niche to help you and your furry friends at home stay comfortable and sighted!
Lisamarie, Katie, Christina,
Continue reading Merry Christmas!
The eyelid is involved in many diseases that we see and treat on a regular basis. Its function to protect the eye is an important one, whether it be to act as a barrier to prevent direct trauma, to limit bright light irritation or to distribute the tear over the corneal surface. Some species have an extra lid where others have no lids at all! I’ll take a couple of posts to address the lids and we will concentrate on congenital issues here. So take off your lid and stay awhile as we talk about the eyelid and some of
Continue reading Put a lid on it!
A common comment veterinarians hear is about how our job is so difficult with a patient that cannot tell us what is wrong. Well, sometimes less is more! Our patients talk to us in different ways with clinical signs and symptoms that help us determine what and where the problem is without the confusion of speculation and interpretation and emotional embellishment of those features that we all do as humans. We use our senses and powers of observation along with listening to the heart and lungs and palpation of the body to get most of the answers in general practice.
Continue reading How do you see what you’re doing?
I can’t believe the way time has sped along here in the Northeastern United States. We have gone from storm to storm this year, enduring “hurricanes” in the summer to heavy snow at Halloween which combined for almost 2 weeks of life without power at both my home and the clinic. No good sales on generators this holiday season you can bet! Thanks to battery powered equipment, we were able to cobble together a service for those of you with non-surgical problems that inspection, conversation and medication could provide an answer. Thanks to all who survived these times and even
Continue reading Looking ahead to the New Year
Sassie and Dr. Stuhr
It has been a decade since I became the sole owner of the Animal Eye Clinic in Wilton and it stuns me to think of all that has happened over that time. When Dr. David Covitz gave me the keys and I promptly found the basement in the old clinic had flooded the next morning, it hit me right between the eyes that this was now my baby to care for and shape into the practice I wanted it to be. Ten years later, I can gladly say that the journey so far has been a
Continue reading My Ten Year Anniversary