We know that glaucoma in dogs and cats is caused by imbalance in the pressure of the eye, otherwise known as intra-ocular pressure. This ocular pressure increases due to an abundance of fluid in the eye that isn’t drained as quickly as it is produced. The reason fluid drainage slows down depends on the type of glaucoma your pet has.
There are two types of glaucoma that occur in pets: primary glaucoma and secondary glaucoma.
Healthy, disease-free eyes develop primary glaucoma due to inherited abnormalities. Genetic predisposition to an abnormal drainage angle is the main reason pets will form increased intra-ocular pressure. Primary glaucoma generally begins to develop in middle-age or older age animals, but can show up at any time.
Dog breeds that are genetically predisposed to primary glaucoma include:
- Basset Hounds
- Great Danes
- Shar Peis
Cats are far less likely to have primary glaucoma than dogs. However, the cat breeds that are most susceptible to primary glaucoma include:
- Some domestic shorthair cats
Though these breeds are most susceptible to primary glaucoma, the genetic abnormalities that cause it can be passed down in any breed. Primary glaucoma may develop in one eye before the other, but eventually, both eyes will be affected by glaucoma. Pets that have primary glaucoma are not recommended for breeding.
Secondary glaucoma stems from disease or an injury to the eye. This form of glaucoma is more common in cats than primary glaucoma. Reasons for the development of secondary glaucoma include:
- Chronic infection or inflammation that produces debris and scar tissue that block the drainage angle.
- Eye tumors that block the drainage angle.
- Lens luxation, which occurs when the lens dislocates and blocks the drainage angle.
- Advanced cataracts that bring on the onset of lens-induced inflammation can also lead to glaucoma
Treatment of secondary glaucoma involves fixing the underlying eye problem. In some cases, only one eye will be affected by secondary glaucoma.
Each type of glaucoma stems from different conditions within the eye, but yields the same results. Your vet will test for primary and secondary glaucoma to determine the proper treatment route.
This information is for informational purposes only and is not meant as a substitute for the professional advice of, or diagnosis or treatment by, your veterinarian with respect to your pet. It has, however, been verified by a licensed veterinarian for accuracy.