Glaucoma is a common condition that affects humans and dogs alike. Left untreated, it can lead to blindness, so it’s important for dog breeders to be aware of the early signs. Glaucoma is caused by an increase in pressure in the eyes causing inadequate fluid drainage. If it is left untreated, it can cause damage to the optic nerve and is also very painful for the dog.
Some dog breeds are more likely to suffer from glaucoma, so it’s important to be aware that beagles, basset hounds, cocker spaniels, poodles, chow chows and Siberians are at higher risk.
What causes glaucoma?
There are two types of glaucoma, primary and secondary. Primary glaucoma is usually caused by genetics and will often affect a dog around two or three years of age. The exact cause will vary based on the breed, but it could be caused by naturally narrow angles or eye drainage pores that are too small.
Secondary glaucoma is often the result of another condition, such as trauma to the eye. A wound to the eye which results in an eye infection can lead to high pressure in the eye. An infection can cause the fluid in the eye to thicken and result in decreased drainage.
What are the symptoms of glaucoma?
Depending on the type of glaucoma, the signs you will need to look out for will vary.
- Excessive blinking
- Receded eyeballs
- Red blood vessels in the white of the eye
- Cloudy appearance of the eye
- Dilated pupils that don’t respond to light
- Vision problems, which will be noticeable if your dog has a sudden change in behaviour.
Behavioural changes may also be apparent, so if you see your pet pressing his head to the wall, there is a chance he is trying to relieve a headache caused by increased pressure in his eye. Your dog may also lose his appetite or display a change in behaviour, such as not wanting to play.
How is glaucoma diagnosed?
If you suspect your dog is suffering from glaucoma, a trip to the vet will help to confirm your suspicions. It’s important that you can give an accurate account of the symptoms and the timescale in which you noticed them. Your vet will be able to measure the pressure in your dog’s eyes using a tonometer. Your pet may also be referred to an ophthalmologist if required.
How is glaucoma treated?
In order to save your dog’s vision, your vet will prescribe drugs to try to normalise the pressure in your pet’s eyes. If your dog's glaucoma has gone unnoticed for a long time, surgery may be required to correct the problem. If caught early, your vet may be able to drain the excess fluid and prevent future build-up by killing the cells that produce intraocular fluid. This process is called cyclocryotherapy and can be effective in halting the progression. If it isn’t caught in time, some dogs will simply have to adjust to their life without sight. Dogs often lose sight in one eye at a time, so they have time to adjust to the change, and your vet will have the opportunity to stop the development in its tracks.