You love those puppy eyes, and your dog knows it. Like humans, a dog's eyes can be susceptible to eye diseases that can damage their sight.
One of those is a condition called glaucoma.
What is Glaucoma in Dogs?
Glaucoma is a condition that results from excessively high pressures within the eyes. One of the main causes of glaucoma is inappropriate drainage of the fluid within the eye.
Increased pressure will damage the eye, leading to decreased vision and even blindness. Unfortunately, even with prompt treatment, up to 40 percent of the dogs diagnosed with glaucoma will lose their eyesight to it with the first year.
What Causes Glaucoma in Dogs Eyes?
Glaucoma develops when there is imbalance between the amount of liquid in the eye and the amount naturally drained from it.
This leads to increased pressures that can damage the optic disk - the point where the optic nerve enters the eye. The retina can be damaged as well.
It is estimated that glaucoma only affects around 1.7% of all the dogs in North America. Within certain breed gene lines it is a common hereditary condition.
Breeds predisposed to glaucoma include:
- Terrier breeds, especially the Jack Russell Terrier
- Chow Chows
- Cocker Spaniels
- Shar Peis
- Shiba Inus
- Great Dane
- Alaskan Malamute
- Basset Hounds
- Labrador Retrievers
- Border Collies
All of these breeds are statistically more likely to develop glaucoma in their lifetime versus other breeds.
This does not mean that they will, but it does mean that their pet parents should be aware of the risk and informed about what to look for in terms of warning signs.
Are There Different Types of Glaucoma?
There are two main types of glaucoma commonly diagnosed in dogs: primary and secondary.
Primary glaucoma is associated with an inherited malfunction in the drainage angle and is a leading cause of incurable vission loss in dogs.
Secondary glaucoma occurs as the result of another, unrelated eye infection, such as a trauma to the eye, tumor, cataracts or inflammation in the eye.
Secondary glaucoma is diagnosed more often than primary, and that fact highlights the need to be vigilant about a dog's general eye health.
Signs Your Dog Has Glaucoma
The clinical signs your dog might display if developing glaucoma will vary according to the type.
The general signs of glaucoma noted by owners are:
- Excessive blinking
- Redness or apparent broken blood vessels in the eye
- A blue or cloudy patch visible on the front of the eye
- An obvious decrease in visual ability
- A dilated pupil - ie: a pupil that does not respond properly to light
- Eye discharge
- Vision loss
All of these signs can occur with primary and secondary glaucoma.
If the disease progresses you may also notice:
- A receding of the eyeball
- A swollen or enlarged eyeball
- Additional vision loss
If the dog is developing secondary glaucoma their clinical signs will differ somewhat and include any of the above-mentioned signs as well as:
- Visible debris at the front of the eye
- Loss of appetite
- Loss of energy
Some clinical signs of both types of canine glaucoma can apply to other diseases and health conditions as well, so it is important that you visit your veterinarian as soon as possible to obtain a definitive diagnosis.
How is Glaucoma in Dogs Diagnosed?
To achieve a definitive diagnosis of glaucoma your dog will need both a thorough ocular examination and a number of tests.
Initially a veterinarian will test the amount of intra-ocular pressure in the dog's eye using an instrument called a tonometer.
The test is painless and easy to perform.
If the pressure in an affected eye is elevated, it can be very painful, so the most important thing, from a medical standpoint, is for the pressure to be reduced as quickly as possible.
This will both relieve the pup's pain and reduce any long term damage to the eye.
Uncontrolled glaucoma is painful and blinding.
Dog Eye Glaucoma Treatments
Treatment is available for glaucoma and can be grouped into medical and surgical.
The medical treatment involves the use of anti-glaucoma eye drops to bring down the intraocular pressure. If eye drops are successful in bringing down and maintaining optimum intraocular pressure, this treatment would have to be continued for the rest of a dog's life.
If this treatment does not restore normal eye pressure, a dog may need to undergo a surgery along with life long medications and regular examinations.
If the disease is caught early, this, along with regular check-ups and sometimes anti-glaucoma medications, can be enough to halt the progression of glaucoma.
In other cases the eye cannot be saved and must be surgically removed.
The surgical removal of the eye is distressing for the pet parent, but it is a procedure that may be necessary to save their pup from a great deal of pain. If only a single eye is affected the healthy eye will be monitored closely going forward.
It should be noted that this condition more often than not affects the remaining eye, with many owners reporting an average of a year before the second eye develops the same infection.
Glaucoma surgery involves the use of an intraocular laser to reduce the production of intraocular fluid by the eye.
Surgical options are performed under general anesthesia include an intrascleral prosthesis (or artificial eye), or sometimes complete enucleation (or removal) is mandated.
Typical enucleation (eye removal) surgery costs anywhere between $1,950-$2,200.
Recovery and Prevention
It should be noted that once diagnosed the treatment for glaucoma is almost always a long term commitment, even if the affected eye(s) are saved.
It may surprise you to learn that most dogs will take the loss of an eye or both eyes in stride rather well.
They have often been losing their vision slowly and have begun to adapt. The eye socket can either be sutured closed or filled with an orb and, with careful monitoring the pup can live a normal life.
Those whose dogs come from one of the dog breeds prone to glaucoma often want to know if there is anything that can be done to prevent its onset.
There is no magic bullet to offer here, and medical experts are still working on research to better prevent and treat glaucoma, but a focus on eye health in general can be helpful.
This can include ensuring that your pup gets the 'eye healthy' nutrients he needs in sufficient amounts. These include Vitamins A and C, beta-carotene, and lutein.
It's also important to monitor your dog's eye health and be aware of the fact that less serious eye problems can lead to secondary glaucoma so should be treated immediately.