Glaucoma in dogs is an ocular disease that can cause irreversible damage to the eyes. 40% of dogs with glaucoma become blind in the affected eye within the first year despite receiving medical treatment.
Understanding the causes and early-stage signs of glaucoma play an important role in preventing this condition from advancing and choosing the right treatment.
What Is Glaucoma in Dogs?
Glaucoma in dogs refers to the abnormal increase in intraocular pressure (IOP) in the eyes. It occurs when the ciliary body produces inadequate amounts of aqueous humor, a fluid that nourishes the eyes and maintains pressure within the eyes.
Open-angle glaucoma is a painless chronic eye condition characterised by a slow loss of vision due to damage or abnormalities in the eye’s drainage canal.
On the other hand, closed-angle glaucoma is characterised by a sudden increase in eye pressure with redness and severe pain.
The high pressurized state of the eyes causes a debilitating effect on the retina and the optic nerve. This can result in gradual loss of vision leading to blindness.
What Are Types of Glaucoma in Dogs?
Glaucoma in dogs has several causes and they are divided into two categories: primary and secondary.
Primary Glaucoma in Dogs
Primary glaucoma in dogs happens when there is an abnormality in the iridocorneal angle, which is responsible for draining aqueous humor from the eyes. It is usually hereditary and commonly seen in dog breeds like:
Dogs can develop glaucoma of this type at any age. However, most canines with this condition are diagnosed around 3-7 years old. Unfortunately, this type of glaucoma in dogs is incurable and therefore needs long-term treatment.
Secondary Glaucoma in Dogs
Secondary glaucoma in dogs is caused by an underlying illness or injury causing increased pressure in the eyes. Tumours or inflammations can affect the production of aqueous humor or block the iridocorneal angle. Diseases that can lead to the development of secondary glaucoma in dogs are:
- Intraocular neoplasia
- Lens luxation
- Retinal detachment
Early detection and treatment of secondary glaucoma can prevent vision loss in affected dogs.
How Long Is the Duration of Glaucoma in Dogs?
The duration of glaucoma in dogs can be classified into 2 types: sudden or chronic.
Sudden Glaucoma in Dogs
Sudden onset glaucoma in dogs, as its name suggests, manifests quickly causing an abrupt swelling in the eyes. It has less than 12-24 hours’ duration. When treated immediately, dogs with sudden glaucoma can be saved from vision impairment.
Chronic Glaucoma in Dogs
Chronic glaucoma in dogs develops at a slower pace. It can cause sustained high elevations of IOP for days or more. Although treatment can reduce eye pressure, loss of vision cannot be reversed.
What Are the Symptoms of Glaucoma in Dogs?
Keeping an eye out for early clinical signs of glaucoma is important. Failing to detect this condition within hours of its onset can lead to permanent blindness in dogs.
Early-stage signs of glaucoma in dogs may include:
- Slightly dilated pupils
- Subtle bulging of the eye
- Mild obstruction of the conjunctiva’s veins
Most common symptoms of glaucoma in dogs:
- Cloudy corneas
- Light sensitivity
- Appetite loss
- Inflamed eyes
Less common symptoms of glaucoma in dogs:
- Watery eye discharge
- Excessive tearing
Glaucoma in dogs rarely occurs in both eyes at the same time. Nonetheless, it has a high chance of affecting the other eye if left untreated. In most cases, it can take years for glaucoma to affect the second eye.
Is Glaucoma in Dogs Painful?
Glaucoma in dogs is an excruciatingly painful ocular disease due to the building pressure inside the eye. Be watchful for any signs of eye pain on your dog and send him to the vet right away for examination.
How To Tell If Your Dog Has Vision Problems Due to Glaucoma?
Vision problems can be attributed to several eye disorders. Proper vet diagnosis helps discern if your dog’s impaired eyesight is caused by glaucoma.
Aside from inquiring about your dog’s medical history, the veterinarian will also run a few diagnostic examinations on him including:
- Diagnostic imaging such as x-ray or ultrasound will be performed if the affected eye is suspected to have tumours or abscesses. These tests also provide a close inspection of the eye in cases of injury or trauma.
- Tonometry is one of the reliable tests for diagnosing glaucoma in dogs. It involves measuring your dog’s IOP using an instrument such as a TonoVet or a TonoPen. The normal IOP for canines is around 15-25mmHg. Both eyes should have similar IOP measurements. If there is a difference of over 10 mm Hg between each eye, it suggests your dog has glaucoma.
In cases wherein the results of tonometry are inconclusive, the vet may refer you to a veterinary ophthalmologist, who will run a gonioscopy on your pet. This test examines his iridocorneal angle for abnormalities, which is indicative of glaucoma.
How Is Glaucoma in Dogs Treated by the Vet?
The main objectives of glaucoma in dogs treatment are to lower the risk of permanent vision loss and treat the underlying disease causing the eye disorder if there is any. Below are the treatment options available for dogs with glaucoma:
Topical ointments are prescribed to reduce eye pressure and stop inflammation or infection. Intake of analgesics will control the pain and discomfort caused by glaucoma in dogs’ eyes. Below are other oral medications used to treat this condition:
- Beta-blockers and carbonic anhydrase for decreasing fluid production in the eyes.
- Cholinesterase inhibitors hinder the progression of glaucoma to the unaffected eye.
- Corticosteroids mitigate eye inflammation.
- Mitotic medications stimulate the pupil to contract, which promotes fluid release.
- Prostaglandin analogs increase fluid flow in the eyes.
Severe cases of glaucoma in dogs will require hospitalization since the treatment involves injectable medications to help lower IOP swiftly.
There are several types of surgical treatments for various cases of glaucoma in dogs. The most common are:
Enucleation is the complete surgical removal of the affected eye. It is the treatment option for end-stage glaucoma in dogs. This relieves the pain and discomfort frequently accompanying the condition.
Cyclocryotherapy is a laser treatment used to eliminate the ciliary body to decrease eye pressure. It can successfully stop or hinder the progression of glaucoma in dogs during its early stage.
For this medical procedure, a small tube is implanted inside the eye to support fluid drainage. Gonioimpantation prevents elevated IOC and further deterioration of eyesight in dogs with glaucoma.
Can a Dog Live With Glaucoma?
Glaucoma is not a life-threatening disease. Most dogs can live long and normal lives despite having this condition.
However, those with primary glaucoma are very likely to lose their eyesight even with proper treatment. Secondary glaucoma in dogs has a better prognosis if the underlying condition is successfully treated.
Home Remedies for Glaucoma in Dogs
Dog glaucoma early stages can be treated with home remedies. Here are 3 natural treatments to reduce eye pressure and prevent glaucoma from escalating:
Coenzyme Q10 (CoQ10)
CoQ10 is a powerful antioxidant with anti-inflammatory properties that alleviates the symptoms of glaucoma in dogs. Many pet stores have CoQ10 on their shelves.
The recommended amount of CoQ10 for dogs is 1 mg per lb of body weight per day. The easiest way to administer it to your dog is to mix it in his meals.
This herb is known for promoting good eye health. If given to dogs with glaucoma, fennel can reduce the pressure of their damaged eye. The rule of thumb is to add 1 teaspoon of fennel for every 10 pounds of your dog’s body weight.
Carrots are rich in beta-carotene which protects eye cells from damage. Grate or mince carrots into small pieces and then add 1 teaspoon per 10 lbs of body weight to your dog’s food. Do this at least once a day.
How To Prevent Glaucoma in Dogs
Primary glaucoma in dogs is not preventable but close monitoring helps with early detection. Breeds predisposed to developing glaucoma should have an eye check-up every 6 months. Any signs of this eye disease warrant a vet examination.
Secondary glaucoma can be prevented by ensuring your dog is safe from injuries and accidents. Switch from using tight collars to harnesses since the former increases eye pressure. With the vet’s approval, give your dog supplements that promote eye health such as beta-carotene and lutein.