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.