Please come visit us at our office on Danbury Road in Wilton:

lotsofpics 029

The Pressure is Rising

Glaucoma is a painful, blinding disease that by definition is an increase in the pressure inside the eye. It is a bummer of a disease, probably the worst one we see. Why? Because no matter what approach is taken to attack this disease, our goal is usually to delay, not prevent, vision loss. This doesn’t paint a real rosy picture. But as long as this is understood, then together we can make educated decisions on how we want to manage the problem. Let’s talk a little about this entity and see if I can make it a little easier to process.

ANATOMY

The eye is divided into two divisions, the anterior (or front) segment and the posterior (or back) segment. The posterior segment is filled with a firmer, gelatinous substance called the vitreous. The anterior segment is filled with fluid called the aqueous humor. The aqueous is produced by the ciliary body, which is behind the iris, and migrates forward through the pupil and out through the drainage angle that is in the peripheral part of the eye in front of the iris. Light from outside passes through the clear cornea, aqueous, lens and vitreous to hit the retina which then organizes and send a signal up to the brain via the optic nerve.

Pathway of aqueous humor

Pathway of aqueous humor


HOW DOES PRESSURE GO UP?

Trouble arises when this pathway of fluid from gland to drain becomes obstructed. Glaucoma comes in two flavors, primary or secondary. With primary glaucoma, the drain is abnormally formed and quits working sometime in adulthood without warning. In secondary glaucoma, the drain is normal but becomes obstructed with inflammatory debris, blood, lens material, tumor cells, etc., that will affect its function. The end result of both forms is the same which is an elevation of pressure inside of the eye since the gland continues to produce fluid that can’t escape outside the confines of the globe. The internal structures, and specifically the optic nerve, can’t handle pressure rise too well which results in damage. With the nerve, this results in peripheral vision loss initially that can progress to complete blindness. Steady elevation of pressure may go unnoticed in our pets as quality of vision is impossible to assess and they may not complain. However, if the pressure spikes rapidly, complete vision loss can occur in short order which is coupled with signs of pain, redness and haze.

You might think that we as owners will pick this up immediately and come rushing our pet into the hospital. Alas, this is not always the case. Dogs can fool us with vision loss in only one eye to the point where many are surprised when irreversible vision loss in the affected eye comes on the initial assessment. This speaks to two things. First is the disastrous nature of a high pressure rise and the minimal amount of time we have to truly recognize the issue, diagnose the problem and treat appropriately. Second is that we may perceive the redness and assume it is something simple like allergy or trauma that may go away on its own. We may take our pet into the hospital if improvement isn’t noted in a week or two which may be too late if pressure was up the entire time.

So what is the trigger? Well, many things depending on the cause. With primary glaucoma, the drain appears to quit working without warning or inciting cause in certain breeds. With secondary glaucoma, the list is long. Inflammation from trauma, immune-mediated disease, cataract formation, infectious diseases to name a few. We can see blood in the eye from trauma, clotting disorders, retinal detachment or tumors that obstruct the drain. Tumor cells themselves, or inflammation due to the presence of a tumor, can compromise the drain. The causes are varied and differ between species as well, with some entities more likely in one versus another. This creates a confusing and challenging dilemma for both owner and doctor to determine the underlying etiology.

To top it off, primary glaucoma is a disease of both eyes but is usually not symmetrical. Thus, we may lose with the first eye, especially if detected late in the course of the disease, and still have to concern ourselves with the time to onset in the remaining eye. This may not be the case with secondary glaucoma where the second eye may not necessarily be at risk if the cause of the pressure rise is unique to the affected eye. Sometimes a primary benign ocular tumor with secondary glaucoma may be a “good” diagnosis because the other eye is not at risk.

congenital glaucoma 2

TREATMENT:

Medical and surgical management of glaucoma is dependent on whether it is primary or secondary and if there is vision potential or not. In dogs with acute primary glaucoma where vision retention or recovery is an option, drugs are used to try to decrease the production of fluid or increase the ability of the fluid to exit the eye. Multiple drugs, given topically, orally or intravenously, are usually warranted due to the time sensitive nature of this disease. In general, you want to throw the “kitchen sink” at these eyes, hope the pressure drops, and then reduce drugs if possible while you assess if vision returns and pressure remains within a normal range. We occasionally with tap the eye and manually remove some of the fluid to get a jump start on the IOP as sometimes it is more effective to do this and then try to keep the pressure low with drug rather than try to drive the IOP down with drug. If pressure is tenuously controlled or IOP will not drop with drug, surgical options to focally destroy the gland with laser energy and placement of a man-made valve to help with outflow can be considered. Again, the long term prognosis is guarded to poor so our goal is to try and delay vision loss for as long as we can. This is usually a more aggressive disease than seen with humans since we are dealing with higher pressures in eyes that get more inflamed. Many of the procedures used in humans don’t work in the dog due to species variation.

Gonioimplant (valve) into eye at the 2 o'clock position

Gonioimplant (valve) into eye at the 2 o'clock position

If you have secondary glaucoma, treatment is directed towards addressing this entity, like significant intraocular inflammation, along with addressing the pressure. Thus, systemic antiinflammatories may carry a greater importance here.

Unfortunately, most dogs and cats that present with glaucoma may already be out of that small window where vision can be recovered. In these cases, our goal is comfort and cosmetics over vision. Medical management as above may be utilized to see if we can control the pressure, and maintain comfort, with a manageable amount of drug. If not, surgical options to achieve these goals by either removing the eye, placing an ocular or orbital prosthesis, or injection of drug into the eye to destroy the gland are our options. Although these can sound drastic, our pets do fantastically with them by relieving the migraine headache pain associated with this disease. This discomfort may not be externally evident if chronic, i.e. not squinting or rubbing, but positive changes in temperament and personality are usually an obvious sign that they feel better. An extensive discussion of these procedures are found in a prior post titled “Losing an Eye: Its not as bad as you think”.

New technology, old fashioned service

Cat-Using-Google crop

Email! Tweets! Snapchat! Instagram! Facebook! Yikes!!!

We have so many ways to communicate with each other and yet the art of communication seems to be getting lost in the chaos.

Multitasking, usually in the form of a downward stare at a cell phone, occurs constantly in our society even if the action is right in front of our face. We try to stay one step ahead of our day, knocking out an errand while doing another, getting a jump on the next event all while staying in time with the constant deluge of emails and texts that raid our devices. Not that many of these communications are truly that urgent, but we have chosen to make them so. If one doesn’t respond in an hour the alarm bells ring. Can’t be reached? C’mon, that’s impossible these days unless you make the effort to hide.

Now I get this, sometimes our days’ dealings warrant a constant level of information and communication. Staying abreast of each others actions, the movement in the market or changes in the geopolitical scene, for example, dictate we keep in touch. Or even more familiar, a child’s constantly changing schedule of school, practices and lessons that alter last minute due to weather delays that plague a parent’s well-thought-out day. Thank goodness for the cell phone then!

So what does this have to do with your pet’s eye problems and the Animal Eye Clinic? For one, people want information so they can make educated decisions. So they look up what they think is their pet’s problem based on external symptoms and come in with lots of questions along with a touch of anxiety based on all the different diagnoses they were able to research on the web. A red eye? Oh my, the things you might find are endless! Our goal here is to decrease your worry and anxiety by narrowing that list of issues with diagnostic tests or, even better, by giving you a definitive diagnosis with specific treatment options. We give this information to you verbally and in writing in case you are overwhelmed and forget what was said. This also insures that you will be looking up the right disease if more information is what you need. What a relief!

Just as importantly, you know you will be getting our total attention as we are firmly fixed in the present to take care of you and your pet. My staff, many who have been with me for years, will look you in the eye, say hello and take your history upon arrival. I create the time and space in our comfortable and friendly office to sit down and examine your pet and then talk about all the things I see. We give you this information so you feel comfortable and don’t just give you a short handout and a prescription to fill. We try our best to run on schedule for your appointment as we know your time is important too! Our goal is to educate and communicate and that is what makes this practice special.

I could certainly be busier, double booking appointments, hustling in and out of exam rooms and leaving you and Dr. Google to sort through the details. That’s just not our style. All we ask of you is to unplug from the world and turn off your phone for the time it takes to examine your friend and impart this information. Be an active participant in your pet’s health knowing that all the craziness of the world, the emails and texts, will still be waiting when you leave the building! As an advocate for your pet, I want to insure that you also leave smarter than when you entered with less anxiety, more information and a feeling that you and your pet are in good hands.

A Change in the Season

I must confess, I have been remiss at updating my post here at the Animal Eye Clinic. Part of this was intentional, as the last post describes the new cataract surgery machine we purchased last year that is working like a charm. Changes in technology are fascinating and very rewarding when we, as veterinarians, find one that applies to our patients and is cost effective in this ever-changing world of health care. Part of my delay was unintentional, as changes of the kids’ school, health of relatives, staffing and life in general often reworks our life and schedule when we

Continue reading A Change in the Season

Technology Upgrade for Cataract Surgery at the AEC

Cataract surgery in the dog is a highly successful procedure that many owners have chosen for their four-legged friends to regain or improve vision. Cataracts in general and a brief discussion of the preoperative workup and surgery is presented in a prior post that you can peruse if interested titled Cataracts in the Dog. (You can find this older post if you scroll to the bottom of this page and click on Older Entries.) Removal of an opaque, cataractous lens is an elective procedure that is chosen if we feel we can improve our dog’s quality of life by returning

Continue reading Technology Upgrade for Cataract Surgery at the AEC

Summertime Blues!

Summer is here in New England and hopefully all are out and about doing what they like to do when the weather is warm. If anyone complains of heat and humidity I am going to send them right back to February so they remember what cold feels like! I am a sun and fun lover so you won’t hear me complain…no summertime blues for me!

Blue shows up in veterinary medicine in a handful of different ways. We have blue-eyed dogs and Russian Blue cats, blue merle coloring and Blue Amazon parrots. When the eye is blue, that usually refers to

Continue reading Summertime Blues!

ACVO Diplomates Giving Back

I am always in awe of how animals enhance and improve our daily life. Whether it is the friendly greeting every day when I come downstairs in the morning or the benefit of the evening walk that I do even if I am not in the mood, to see that unrestrained, unconditional love regardless of the day or mood is priceless. The warm body on a lap during a cold day, the cat rubbing up on your legs awaiting some attention, the look of earnest when you are feeling down, pets of all types fill a very important niche in

Continue reading ACVO Diplomates Giving Back

Those darned corneal erosions that won’t heal!

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

Continue reading Those darned corneal erosions that won’t heal!

Losing an eye; it is not a bad as you think…

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

Continue reading Losing an eye; it is not a bad as you think…

A Warm Environment in the Cold Weather

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

What is the coolest animal you have seen?

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?