Why Does Eye Pressure Rise in Dogs?

Glaucoma, also known as eye pressure, in dogs is a health problem that requires early diagnosis and the correct treatment methods. Undiagnosed and untreated glaucoma can lead to vision loss. In this article, you can find answers to frequently asked questions about glaucoma in dogs.

Eye Pressure in Dogs

Glaucoma in dogs is a health problem that leads to an increase in intraocular pressure. In the diagnosis of this disease, also known as eye pressure, it is essential to measure the intraocular pressure with an instrument called a tonometer. As a result of the increase in intraocular pressure, damage may occur in the retina or optic nerves, and blindness may develop.

What is Intraocular Pressure?

Intraocular pressure is created by the filtration of blood fluid by the ciliary extensions of the aqueous humor. The resulting light fluid fills the space between the cornea and the iris. This fluid also nourishes the cornea and lens, creating intraocular pressure and giving the eye its shape. The fluid that creates intraocular pressure carries the nutrients and oxygen needed by the structures within the eye. Excess fluid is drained as it circulates between the cornea and the iris. Intraocular pressure remains constant when fluid production, absorption, or drainage are at equal levels.

What Causes Glaucoma in Dogs?

Glaucoma, or high eye pressure in dogs, occurs as a result of insufficient absorption or drainage of fluid within the eye. Although increased intraocular pressure might seem like it could also occur due to excessive fluid production, it is actually not related to excessive fluid production. Glaucoma in dogs is classified as primary or secondary glaucoma.

Primary Glaucoma: This can be described as an increase in intraocular pressure in a healthy eye. Primary glaucoma is more common in some breeds. Primary glaucoma occurs due to inherited anatomical anomalies in the drainage angle. Breeds such as Akita, Dalmatian, Norwegian Elkhound, Cocker Spaniel, Chow Chow, Great Dane, Siberian Husky, Samoyed, and Bull Mastiff have a higher probability of developing primary glaucoma.

Secondary Glaucoma: Glaucoma that occurs as a result of increased intraocular pressure due to a disease or injury to the eye is called secondary glaucoma.

Causes of secondary glaucoma;

• Intraocular inflammation causing scar tissue that blocks the drainage angle,
• Severe intraocular infections,
• Lens falling forward and consequent failure of fluid absorption,
• Tumors,
• Intraocular hemorrhage,
• Advanced cataract,
• Damage to the lens can be described as such.

What are the consequences of increased intraocular pressure?

High intraocular pressure causes damage to the retina and optic nerve. The retina is the innermost lining of the eyeball. This layer contains light-sensitive rods, cones, and cells that convert images into nerve signals. The optic nerve is the nerve located at the back of the eye that goes to the brain. It transmits signals from the retina to the brain, enabling vision. These two structures can be deformed by increased intraocular pressure, resulting in vision loss.

What are the Symptoms of Increased Intraocular Pressure in Dogs?

Glaucoma, or increased intraocular pressure, in dogs can cause much more severe pain than in humans. However, dogs cannot express their health problems like humans do. Therefore, it can be difficult to understand when they are in pain. Symptoms to watch out for regarding glaucoma in dogs include: These symptoms may include:

• Eye pain,
• Eye redness,
• Squinting,
• Bulutlu kornea,
• Light aversion,
• Weakening of blinking,
• Eyelid movement,
• Prominent vascular structure in the white of the eye,
• Eye swelling,
• Vision problems.

You should take your dog to a veterinarian as soon as you notice any of the above symptoms. Glaucoma, if not treated in time, can cause severe pain as well as vision loss.

In dogs, glaucoma should be treated before it causes irreversible damage and risks blindness. Therefore, the cause of the intraocular pressure should be identified and treatment started as soon as possible. Medication is frequently preferred for this health problem. In cases where medication is ineffective or in advanced cases, surgical intervention should also be considered.

Medication: Medication can be used to lower intraocular pressure and bring the pressure back to the normal range as soon as possible. Topical medications are preferred to lower intraocular pressure, and medication may also be recommended to control the pain caused by the problem.

Cyclocryotherapy: This is a procedure that targets the cells that produce intraocular fluid. The fluid can be drained, and the cells can be manipulated to prevent fluid buildup in the eye. This procedure is usually performed in cases of early diagnosis.

Surgery: This is the preferred method if glaucoma remains undiagnosed for a long time. In this case, if the optic nerve and cornea suffer irreparable damage, the need to remove the eye arises. To avoid severe pain in the area, the empty socket can be closed or filled with a prosthesis so that the ocular cavity is not exposed.

After glaucoma is diagnosed and treated in dogs, regular follow-up is necessary.