Glaucoma & Your Dog's Vision in Old Age
Glaucoma is a painful condition caused by pressure within the eye. Our veterinary ophthalmologist explains a few of the reasons that glaucoma can occur in your dog, and how primary and secondary glaucoma can be treated.
What is glaucoma?
Glaucoma is a painful condition characterized by increased intraocular pressure in the eye, caused by inadequate fluid drainage. It can progress very quickly, and often leads to damage in the optical nerve and retina. It is estimated that 40% of dogs may be left blind in the eye with glaucoma.
There are two types of glaucoma, each defined by the cause of the condition; primary glaucoma and secondary glaucoma.
What causes primary glaucoma in dogs?
Primary glaucoma occurs in dogs as a result of inherited abnormalities in the drainage mechanism of the eyes. Dog breeds that show an increased risk of primary glaucoma include (but are not limited to) Boston terriers, cocker spaniels, beagles, shar-peis, basset hounds, toy poodles, Siberian huskies, Labrador retrievers, samoyed, and great danes. Each breed has its own unique traits that may make dogs of that breed more susceptible to glaucoma.
Primary glaucoma does not usually affect both eyes equally or simultaneously. The condition typically occurs in one eye months or even years before it affects the other.
What is the cause of secondary glaucoma in dogs?
Secondary glaucoma occurs as a result of an injury to the eye or disease. The most common causes include: damage to the lens of the eye, inflammation of the interior of the eye, severe intraocular infections, anterior dislocation of the lens (blockage caused by the lens falling forward in the eye), tumors, and intraocular bleeding.
What are the signs and symptoms of glaucoma?
Dogs suffering from either primary or secondary glaucoma may experience one or more of the following symptoms:
- Watery discharge from the eye
- Cloudy, bluish appearance to eye
- Eye pain (eye rubbing or turning away when being pet)
- Bulging of the eyeball (whites of eye turn red)
- Dilated pupil – or pupil does not respond to light
- Vision loss
- Lethargy
- Loss of appetite
- Swelling of the eye
- Less desire to play
While chronic glaucoma often takes some time to develop and begin causing symptoms, acute glaucoma occurs very suddenly. If your dog is showing any of the symptoms listed above, contact your vet immediately or visit the nearest emergency veterinary hospital for urgent care. Early diagnosis and treatment are your dog's best bet for good treatment outcomes.
How is glaucoma in dogs diagnosed?
Our veterinary ophthalmologist will measure the pressure within your dog's eye using an instrument called a tonometer.
If your dog is experiencing blindness due to glaucoma, we may use electroretinography to determine whether surgery can help to restore vision.
How is glaucoma in dogs treated?
Following diagnosis, your vet will prescribe drugs to help reduce pressure within the eye as quickly as possible. Reducing the pressure quickly may help to prevent permanent blindness in some dogs.
Typically, painkillers are also prescribed in order to help your dog feel more comfortable.
Other medications may be prescribed to both promote drainage and decrease fluid production as a way of reducing intraocular pressure.
In many cases surgery will also be an essential part of the treatment for advanced cases of glaucoma. If your dog has permanently lost their vision your vet may recommend surgery to remove the eye in order to relieve pain.
Regular eye examinations will be an essential part of your pet's ongoing care and treatment for glaucoma. Regular appointments allow your vet to monitor symptoms and keep the condition under control over the long term.
What is a veterinary ophthalmologist?
Working alongside your primary care veterinarian, our veterinary eye specialist provides care for all ocular diseases that can impact your dog. While some conditions may require surgery, many can be managed with medications alone.