Some Fun Quotes

With the holidays, I thought I would do a little lighter topic.  Here are some fun pet related quotes:

“Don’t accept your dog’s admiration as conclusive evidence that you are wonderful.”-Ann Landers

“Did you ever walk into a room and forget why you walked in? I think that’s how dogs spend their lives.”

-Sue Murphy

"Dogs are not our whole life, but they make our lives whole." -Roger Caras

"A cat is a puzzle for which there is no solution." -Hazel Nicholson

"Animals are such agreeable friends - they ask no questions, they pass no criticisms." -George Elliot

“Dogs are the leaders of the planet. If you see two life forms, one of them's making a poop, the other one's carrying it for him, who would you assume is in charge.” -Jerry Seinfeld

"I like pigs. Dogs look up to us. Cats look down on us. Pigs treat us as equals." -Sir Winston Churchill

Hope everyone has a happy holiday.

Silly dog, You ate what???

Now that I have discussed hazards among cats, lets talk about problems that dogs may encounter.

1.) Tinsel, ribbons, and ornaments:  Although these decorations are not toxic, they can definitely cause problems with your pets.  In particular, longer, thin decorations can cause major problems as they tend to turn into linear foreign bodies.  Unlike a ball, corn cob, etc that may be eaten and removed fairly easily, longer string like objects tend to get hooked higher up in the stomach and intestine and then continue to move down the intestinal tract.  This leads to a large amount of damage that tends to make it more difficult to remove and heal from.

2.) Holiday lights and candles: The constant flickering of lights or bright colors can be very attractive to pets.  The problem with this is the electricity running through the lights.  You may not get the reaction like in "National Lampoon's Christmas Vacation," but biting into a cord can cause significant mouth burns and possibly death.  Make sure lights are out of the way of your pet.

3.) Holiday food: With the holidays comes baking and cooking, so be cognizant of what you leave out.  Chocolate is a big concern in dogs.  Although all chocolate is bad, baking chocolate contains the most methylxanthines, which can cause heart arrhythmia and death in large enough doses.  Other fatty foods and trimmings can also cause issues.  High fat foods can trigger pancreatitis in your pet leading to vomiting, pain, dehydration, and in severe cases, death.

4.) Antifreeze: Although not really a holiday problem, antifreeze becomes more readily available during colder months.  In the past antifreeze has been enticing to pets due to its sweet taste.  Fortunately, legislation passed last year that requires manufacturers of antifreeze to add a bittering agent to the liquid that will make it less tempting to pets.  Pets only need to be exposed to a small amount of the liquid to cause a problem.  Pets typically succumb to renal failure if they are not treating early and aggressively.

5.) Holiday plants: The good news is that most plants will only produce mild gastrointestinal upset if your pet is exposed to them.  Poinsettias, holly, and mistletoe typically fall under this category, but with large exposures there can be other problems, so always contact your veterinarian.

The best way to avoid a problem with your pet this holiday season is to keep anything that could be a hazard out of their reach.  Have a safe and happy holiday season.

Holiday Hazards

With the holidays quickly approaching I wanted to take time to discuss some holiday hazards to try to avoid.  The first post will deal mostly with cats and is taken from Dr. Tina Wismer's handout from a talk she gave for a rounds discussion in 2010.  Listed below are some common items that a cat might encounter during the holidays along with descriptions of possible problems.

1.) Silica Gel Packs

Desiccant packs are included as moisture absorbents. They are found in shoeboxes, electronics, medications and food. Silica gel comes in paper packets or plastic cylinders. Packages of silica gel are attractive to pets because of the rustling noise, and the packages are easy to bat around. Most ingestions will not cause clinical signs, although a mild gastrointestinal upset may occur. If a large amount is ingested, there is potential for diarrhea occurring. In most cases, the packet will be ruptured and the contents eaten. Ingestion of the intact packet may cause an intestinal obstruction.

2.) Christmas tree preservative

Christmas tree preservatives primarily contain dextrose and NPK fertilizers. The concentration of metals (copper, iron, zinc, magnesium) is usually small in commercial products. Most cats that drink water containing Christmas tree preservative develop no signs. Occasionally we can see mild GI signs, rarely, bacterial/fungal contamination of the water may lead to more severe signs.

3.) Christmas trees

Christmas trees may be one of several species. The most common are: Douglas fir (Pseudotsuga menziesii), Balsam fir (Abies balsamea), Black spruce (Picea mariana), Blue spruce (Picea pungens), White spruce (Picea glauca), Scotch pine (Pinus sylvestris), Norway spruce (Picea excelsa), Red Pine (Pinus resinosa), and Red spruce (Picea rubens). The most common clinical signs after ingestion of the needles are vomiting, anorexia, abdominal pain and depression.

4.) Poinsettias

The toxicity of poinsettias is generally overrated. The plants do contain diterpene esters, but large quantities must be ingested for signs to develop. Most cats just experience mild, self-limiting vomiting that resolves with little to no treatment.

5.) Mistletoe

Most ingestions involve American mistletoe (Phoradendron spp.). Mistletoe contains lectins, but ingestion of a few leaves or berries will generally cause just a mild gastritis. If purchased in a store, the berries frequently have been removed and replaced with plastic "berries" which can be a foreign body. Large ingestions may require decontamination and cardiovascular monitoring.

6.) American Holly

American holly (Ilex opaca)is a member of the Aquifoliaceae family. All parts of the holly plant are considered to contain potentially toxic compounds, including methylxanthines, saponins, and ilicin. True toxicoses not generally expected in cats. Most ingestions cause gastrointestinal irritation and depression. Recent ingestions can usually be managed with dilution and monitoring at home.

7.) Lily

Members of the Lilium and Hemerocallis genera (Easter lilies, tiger lilies, day lilies, etc.) cause acute kidney failure in cats. The water soluble toxic principle is unknown. Even minor exposures (bite on a leaf, ingestion of pollen) may result in toxicosis, so all feline exposures to lilies should be considered potentially life-threatening. It should be noted that not all plants with “lily” in the name are members of Liliaceae.

Affected cats often vomit within a few hours after exposure. Within 24 to 72 hours of ingestion, kidney failure develops, accompanied by vomiting, depression, anorexia, and dehydration. Elevations in BUN, creatinine, phosphorus and potassium are detectable as early as 12 hours post ingestion. Creatinine elevations may be especially high.

In severe cases, death or euthanasia due to acute renal failure generally occurs within 3 to 6 days of ingestion. When initiated within 18 hours of ingestion, decontamination (emesis, oral activated charcoal, and cathartic) and fluid diuresis for 48 hours have been effective in preventing lily-induced acute renal failure. Conversely, delaying treatment beyond 18 hours frequently results in death or euthanasia. Baseline renal values should be obtained upon presentation and then repeated at 24 and 48 hours. Because the tubular injury from lily ingestion spares the renal tubular basement membrane, regeneration of damaged tubules may be possible. In severe cases, peritoneal dialysis may aid in managing renal failure until tubular regeneration occurs (10-14 days or longer).

8.) Ice Melts

Many brands of sidewalk ice melts are on the market. The most common ingredients in these ice melts are sodium chloride, potassium chloride, magnesium chloride, calcium carbonate, and calcium magnesium acetate. A few ice melts contain urea. Cats may be exposed by walking on the ice melts themselves or by ingesting granules brought inside on the shoes of the owner’s.

Ingestion of urea is not a toxicity issue in non-ruminants. Ingestion of sodium, potassium, calcium and magnesium salts can lead to vomiting and electrolyte abnormalities. Monitor electrolyte levels and treat with appropriate fluid therapy.

9.) Liquid Potpourri

Liquid potpourri is commonly used during the holiday season. Cats are often exposed to liquid potpourri by direct ingestion from simmer pots or spills, or by rubbing against leaky bottles or simmer pots containing the potpourri, or from spilling the containers upon themselves. Oral exposures result following grooming. 

Exposure of cats to some types of liquid potpourris can result in severe oral, dermal and ocular damage.

Liquid potpourri is a combination of cationic detergents and essential oils. Cationic detergents can cause extensive systemic and local effects at concentrations as low as 2%. Local tissue injury caused by cationic detergents resembles that seen with exposure to other corrosives. In addition, cationic detergents can cause systemic toxicity including CNS depression, coma, seizures, hypotension, muscular weakness and fasciculations, collapse, pulmonary edema, and metabolic acidosis; the mechanism of these signs is not known. 

Treatment of local exposure includes dilution with milk or water, pain control (opioids), GI protection (sucralfate slurries) and supportive care (antibiotics, feeding tube). Systemic signs should be treated symptomatically (i.e. fluids for hypotension, diazepam for seizures, etc.).

10.) Alcohol

Due to their small size, cats are far more sensitive to alcohol than humans are. Even ingesting a small amount of a product containing alcohol can cause significant intoxication. Cats are attracted to mixed drinks that contain milk, cream or ice cream (e.g. White Russian, alcoholic eggnog, Brandy Alexander). Ethanol is rapidly absorbed orally and signs can develop within 30-60 minutes. Alcohol intoxication commonly causes vomiting, loss of coordination, disorientation and stupor. In severe cases, coma, seizures and death may occur. Cats who are inebriated should be monitored by a veterinarian until they recover.

 Hope everyone has a safe and happy holiday season!

Stomach Tacking

I have seen a few Great Danes come through the office lately, so I thought I would discuss stomach tacking (gastropexy).  Large breed dogs with deep chests (Great Danes, Irish Setters, Saint Bernands, etc) have a lot more room in the front part of their abdomen that allows for more movement in the stomach and ultimately makes them prone to gastric dilatation and volvulus (GDV or bloat).  

The exact cause of GDV is unknown, but many things can predispose to the condition including

1.) rapid eating

2.) eating one large meal daily

3.) overeating and overdrinking

4.) heavy exercise after eating

5.) conformation of the dog

A dog who has GDV will typically be anxious, may be drooling, have a distended abdomen, and are retching without producing anything.  The condition quickly becomes an emergency as the twisting of the stomach compromises blood return to the heart leading to shock.  The treatment involves immediate treatment of the shock (with fluids and pain medications) and then de-rotating the stomach.  Measures can be taken without surgery including passing a tube to deflate the stomach or passing a needle into the stomach through the body wall, but in most cases surgery will eventually be needed.  Even with surgery it is not guaranteed that the pet will pull through because if blood flow is compromised long enough you may get tissues that die and become infected.

X-ray image of stomach with GDV

The surgery involves deflating the stomach, placing the stomach back into normal anatomical position, and then permanently tacking the stomach to the body wall (which prevents recurrence of GDV).  There are many different procedures to tack the stomach; however, I typically perform a simple incisional gastropexy.  This involves making an incision into the outer portions of the stomach and then making a corresponding incision into the body wall.  The incision is then sutured together using two parallel lines of suture material.  The suture material will initially hold the stomach and body wall together, but eventually scar tissue will form and permanently hold the surgery site together.  If caught early enough, many dogs can do well; however some dogs may need more aggressive surgery (removal of a portion of the stomach, accompanying splenectomy) if the condition goes on long enough.

Tacking stomach to body wall

Because of deep chested breeds risk for GDV later in life, some owners may consider performing a preventative gastropexy.  This involves performing the gastropexy before a GDV occurs (typically done during a spay or neuter procedure).  There are some minimally-invasive techniques involving laproscopy, but not all veterinarians can perform these and the cost will likely be more.  A conversation about this procedure with your veterinarian should be made when the puppy is young, so a plan can be made for performing the gastropexy.

Kidney Disease

What are the functions of the kidneys?

The kidneys play a vital role in the body, participating in a number of processes including removing waste products from the body, regulating water balance in the body, regulating calcium and phosphorus levels, and producing certain hormones for the body.  Blood that passes into the kidney is filtered through thousands of small structures called nephrons where waste products are removed and excessive water is released. 

What is chronic kidney disease?

Chronic kidney disease (CKD) is not a singular disease, but more a catch all term for kidneys that are not functioning at full capacity.  The underlying cause for this could include a number of different conditions including:

• Congenital malformation of the kidneys
• Chronic bacterial infection of the kidney (pyelonephritis)
• High blood pressure (hypertension)
• Diseases of the immune system (i.e. Lupus)
• Recovery from acute kidney disease (toxin, infection, etc) leading to chronic disease

In many cases we do not figure out the exact cause of kidney insufficiency, but treat the end result.

Signs of chronic kidney disease:

Pets with chronic kidney disease can manifest many different clinical signs including:

• drinking too much (polydipsia) and urinating large volumes of urine (polyuria)
• vomiting and/or diarrhea
• lack of appetite and weight loss
• general depression related to the elevation of waste products in the blood (uremia)
• anemia resulting in pale gums and weakness due to a low blood count
• overall weakness from low blood potassium         

How is chronic kidney disease diagnosed?

If a pet is having clinical signs consistent with kidney disease, then some tests will be recommended to evaluate kidney function.  A combination of blood work and urine evaluation is used to give a good indication of kidney function.  Two blood values are of particular concern when evaluating kidney function (Creatinine and Blood Urea Nitrogen (BUN)).  Elevations in these values could indicate that the kidneys are not functioning well. 

If creatinine elevations are seen, then the urine is also evaluated.  In particular, we are looking at the concentration of the urine.  Normally, the kidneys try to maintain proper water balance in the body.  They do this by reabsorbing water and maintaining it in the body.  When the kidneys are functioning properly they will make more concentrated urine.  If the creatinine or BUN is elevated and there is dilute urine, then this indicates that the kidneys are not functioning properly and may have chronic kidney disease.  There is also a staging system (stage 1-4) to help indicate the degree of damage to the kidneys

STAGES	CLINICAL SIGNS	FASTED PLASMA CREATININE mg/dl (umol/l)assessed on at least 2 occasions in the stable patient		EVIDENCE FOR RENAL DISEASE
		DOG	CAT
I	Absent but patients should be substaged with urine protein creatinine ratio and blood pressure measurements	< 1.4 (<125)	< 1.6 (< 140)	Inadequate urine concentration, renal proteinuria, or abnormal renal architecture based on palpation, imaging, or histopathology
II	Usually mild or absent but substage as noted above	1.4-2.0 (125-179)	1.6-2.8 (140-249)	As for stage I
III	Usually present and may be related only to kidneys. Substage as noted above	2.1-5.0 (180-439)	2.9-5.0 (250-439)	As for stage I in addition to clinical signs
IV	Present, but may have extra-renal signs. Substage as noted above	>5.0 (>440)	>5.0 (>440)	As for stage I in addition to clinical signs

Other changes on blood work and urine could include:

• Non- regenerative anemia
• Increased phosphorus
• Low potassium levels
• Calcium is often normal but can be elevated in some pets with CKD and rarely is decreased
• Protein or bacteria in the urine

Other tests may also be recommended including:

1. Abdominal radiographs (x-rays) or ultrasound to evaluate kidney size
   What might this test show?  The kidneys in pets with CRD are usually small reflecting the death of a large number of nephrons. If the kidneys are large then certain causes for the CKD should be considered such as lymphoma (cancer) of the kidneys, or an uncommon disease called amyloidosis. Some pets with signs of kidney disease who have large or normal sized kidneys may have acute kidney failure rather than CKD. The treatment and prognosis for pets with acute kidney disease differs from the treatment and prognosis of pets with CKD.
2. Bacterial culture
   What might this test show?  Bacterial infection is not a common cause of CKD but pets with CKD may develop a bacterial infection as several aspects of the pet's immune system may be less functional when the kidneys are failing.  If white blood cells are observed on microscopic examination of the pet's urine, a bacterial culture of the urine should be obtained.
3. Urine protein/creatinine ratio
4. Blood pressure

What are the treatment options for my pet?

Unfortunately, chronic kidney disease is a progressive disease and is not curable.  However, there are many options available to help treat symptoms and signs associated with kidney disease.  There is no treatment combination that is standard for every pet and many times incremental addition to medications is needed as the disease process progresses.  In some cases, pets may need to be hospitalized for a period of time to replenish fluids and in other cases pets are sent home with conservative treatments.  I will list treatment options available, but remember that an individual pet may not need all these treatments.

• Diet modification:  Studies have shown that pets switched to a protein restricted (high quality protein), phosphorus restricted diet have a higher quality of life, fewer uremic crises, and may live longer than pets fed a regular maintenance diet.  There are many commercially available, prescription diets that meet these standards. 
• Phosphorus binders: Even with phosphorus restricted diets some pets still have elevated phosphorus levels.  In these cases, supplements can be added to the food that help bind more phosphorus and restrict levels even more
• Hypertension medications: High blood pressure often accompanies kidney disease and can lead to further damage to the kidneys.  Monitoring for hypertension and adding anti-hypertensive medications (amlodipine, ACE inhibitors) when present may be warranted in some pets.
• Stomach protectors: Build-up of uremic toxins can lead to stomach upset and inappetence.  Protecting the stomach lining with medications that lower the acidity of stomach contents can be helpful.  Medications can include antacids (famotidine or ranitidine), protein pump inhibitors (omeprazole), or stomach lining medications (sucralfate).
• Anti-nausea medication: Pets may also be inappetent because of nausea.  Cerenia or metoclopramide are examples of anti-nausea medications.
• Omega 3 fatty acids: Supplementing with fatty acids has been shown in some studies to improve survival in pets
• Anemia medications: The kidneys produce a hormone called erythropoietin that signals the bone marrow to make more red blood cells.  With kidney disease, this hormone may be depleted, so anemia develops in patients.  There are commercially available erythropoietin supplements that can be given to increase red blood cell counts.  Pros and cons of this medication should be discussed prior to starting the medication.
• Fluid supplementation: Since diseased kidneys are unable to concentrate urine properly, a pet will lose an excessive amount of water in the urine.  Making sure that water is always available and promoting water consumption is important.  In cases where a pet is not keeping up with fluid loses, either periodic subcutaneous fluids (can be done at home) or intravenous fluids may be necessary.
• Potassium supplementation: Excessive potassium is lost with diseased kidneys, which can lead to loss of energy.  Adding a potassium supplement may be needed.
• Calcitriol: Calcitriol is the active form of vitamin D and helps with regulation of calcium and phosphorus.  It is produced in the kidney, so may be decreased in patients with chronic kidney disease.  To help combat renal secondary hyperparathyroidism, calcitriol may be instituted.  Careful and periodic monitoring of calcium and phosphorus levels is recommended. 

As discussed earlier, not every pet needs every treatment and your veterinarian will evaluate blood work and clinical signs before recommending certain treatments.  Also, some pets are more amenable to treatment (especially in the case of cats) as multiple medications may be needed in a day.  Individual owner circumstances can also dictate how aggressive treatment might be.  With cats, combining multiple medications into a single gel cap may be easier than administering multiple medications at a time.

Goal of therapy:

As chronic kidney disease is not curable, our goal is to provide a good quality of life as long as we can.  Some owners may elect to only change the diet in response to diagnosis, whereas others may add as many medications as reasonable and possible to help their pet.  The goal is to find the right balance for both the owner and the patient.  With proper care some pets with early kidney disease can still live a great quality of life for years.

For more information from the perspective of an owner please visit http://www.felinecrf.com.

Parvovirus

I have recently treated a couple of cases of parvovirus and have had a few scares where the owner suspected parvovirus, so I thought it would be a good idea to discuss the virus and how we can prevent and treat the infection.

Parvovirus, as its name implies, is a virus that attacks rapidly dividing cells in dogs.  Two such areas where cells like this occur in the body are the gastrointestinal tract and bone marrow.  The virus attacking these areas leads to severe diarrhea, vomiting, and a decrease in white blood cells (which usually help to fight off infection).  Without treatment a majority of dogs will die from dehydration and infection.  Even with treatment, some animals may not survive.  It hits puppies particularly hard as their immune system is not fully developed and their ability to fight infection is low.  Un-vaccinated adults can also become infected, but may respond to treatment better since their immune system is usually fully developed.

The virus is picked up when a dog ingest infected soil or other contaminated materials.  It is a very hearty virus and can live in the environment (even harsh conditions) for over a year, so may be prevalent in areas of heavy dog traffic.  After the virus is ingested it replicates in the lymph nodes and then escapes into the bloodstream eventually ending up in the intestinal tract and bone marrow.  Infected dogs will typically have acute cases of vomiting, diarrhea, inappetence, and weakness.  In many cases, blood will be seen in the diarrhea or even the vomit.  Most vets have a good bed-side test for parvo that uses a rectal swab and gives a result in less than 10 minutes.

Because it is a virus, there is not much we can do besides provide supportive care to the pet while the virus runs its course.  Supportive care usually involves hospitalization with fluids, antibiotics, vitamins, nutritional support, and pain management.  If finances allow and it is available, some veterinarians will also treat with plasma that is rich in proteins and electrolytes.  In addition, some vets are using an anti-viral medication called Tamiflu (used against human influenza cases) to help treat parvo cases.  The medication does nothing against the parvovirus, but likely helps prevent the secondary infections that are seen with the cases.  Unfortunately, even with the most aggressive supportive care some dogs may not survive the infection.

The good news is there is a good vaccine to help protect against the virus.  Vaccinations typically start around 6 weeks of age and are given every 3-4 weeks until 16 weeks.  Then, the vaccine is boosted at a year of age.  The parvo vaccine is typically part of the "distemper vaccine" series which includes multiple viruses.  Prior to 6 weeks puppies have some protection if they were able to ingest enough colostrum (mother's milk for the first 24 hours).

So the moral of the story is to make sure that your pet starts vaccinations at 6 weeks of age to prevent this aggressive disease.

Glaucoma

What is Glaucoma?

Put simply, glaucoma is an increase in the pressure inside the eye.  The big question is what is causing the increased pressure.  Before talking about this, let’s talk a little about the inside of the eye.  The eye can be divided into structures in front of the lens and behind the lens.  The globe of the eye behind the lens has a chamber that is filled in with a thicker material called vitreous humor.  In front of the lens the eye contains a thinner material called aqueous humor.  Eye pressures are the pressure inside the aqueous humor.  The aqueous is produced by the ciliary epithelium next to the len.  It then flows forward from the posterior chamber through the iris opening into the anterior chamber and then finally drains out through the trabecular meshwork into the aqueous plexus (and back into the blood stream).  The production of aqueous and its drainage is typically well regulated, but when the production exceeds drainage, pressures rise and glaucoma results.

 What are the clinical signs of glaucoma and how is it diagnosed?

When pets have glaucoma you can notice a number of different signs including redness of the eye, abnormal blood vessels on the eye, different sized pupils, squinting, pawing at the eye, and vision problems.  The diagnosis of glaucoma is fairly straightforward and involves measuring the pressures of the eye and documenting an increased eye pressure.  Most veterinarians have a tool called a Tonopen that accurately and quickly measures eye pressures.  The eye is first numbed; then the Tonopen is pressed against the eye multiple times and records the pressure.  Normal pressures for dogs and cats are between 10-25 mm Hg.  Individual pressures above this confirm glaucoma or a major difference (>8 mm Hg) between pressures in either eye may indicate a problem. 

What causes glaucoma?

The causes for glaucoma can be divided into two major categories: primary versus secondary.

1. Primary glaucoma typically means there is an inherent change (typically breed related) in the drainage angle of the eye that causes reduced drainage of aqueous.  A majority of these are caused by abnormal formation of the drainage angle of the eye that results in a narrower angle and poor drainage (closed-angle).  A smaller subset appears to have a normal drainage angle, but the drainage is still impaired (open-angle).  Breeds where primary glaucoma is common include Cocker Spaniels, Basset Hounds, Schnauzers, Beagles, Poodles, as well as many others.
2. Secondary glaucoma occurs when other eye problems occur that alter the drainage of aqueous.  This may occur if the drainage angle of the eye becomes blocked (due to inflammation, cancer, cyst) or the iris opening becomes blocked (lens luxation or chronic inflammation of the anterior eye chamber).  Long term treatment for this glaucoma is more about treating the primary cause while managing the secondary glaucoma.

How do we treat glaucoma?

The first question to ask when treating glaucoma is whether the eye is still visual, as this will determine what options are available for treatment.  Also, with secondary glaucoma, it is important to treat the underlying cause as this may ultimately fix the problem.

1. Visual Eyes: The first goal for visual eyes is to decrease the pressures as quickly as possible.  The longer the pressures stay elevated the better chance at long term damage to the retina and subsequently vision. 

1. Topical medications: Many topical medications are available that help decrease the pressure of the eyes.  With severe cases of glaucoma multiple medications are started that work in different ways.  In most cases of sudden, severe primary glaucoma a medication to open the drainage angle (latanoprost) along with medications to decrease aqueous production (dorzolamide) are used together.  An intravenous medication called mannitol may also be used that helps draw out some of the vitreous of the eye making more room for the aqueous.  Some eyes with glaucoma respond well to these medications and can be managed with just topical medications for a time.  However, a long term solution usually involves surgery.
2. Surgical options: These options are only available through a veterinary ophthalmologist and financial costs can be very high.  With primary glaucoma the recommendation will usually be a combination of two procedures.  The first is cyclophotocoagulation, which is a procedure that destroys part of the ciliary body (tissue responsible for aqueous production) with a laser.  This helps lower aqueous production.  In addition, some ophthalmologists will also recommend placing a shunt that drains the aqueous humor out into the conjunctiva.  Even with these procedures, topical medications may still be needed and complications can occur.

1. Non-visual Eyes: Once eye pressures have been high enough for long enough the retina will degenerate and the eye will become non-visual.  When this is the case, our goal is to make the pet comfortable (as glaucoma is painful).  If topical medications aren’t working, then a few procedures should be considered.

1. Enucleation: Removing the eye eliminates the problem of the high pressures and pain.  This procedure can be performed by most veterinarians; however, if a prosthesis is desired then an ophthalmologist may be needed.  Even without prosthesis, most owners are happy with the cosmetic appearance of an enucleation.

2. Intravitreal gentamicin injection: This procedure is only available for dogs and there cannot be inflammation present in the eye when performed.  Gentamicin is an antibiotic, but for this procedure is being used because it kills the ciliary body and decreases aqueous production.  It works in around 75% of dogs, but cosmetic changes (cataract, small eye, etc) may be undesirable.  It is typically used as an alternative to enucleation when cost is a factor.

What to do about the other eye?

In many cases primary glaucoma develops in one eye before the other; however, the other eye has the same changes that led to glaucoma in the bad eye.  Starting the other, non-glaucomatous eye on a topical medication can lengthen the time before that eye develops glaucoma.  The typical medications used are either dorzolamide (Trusopt) or timolol (Timoptic).