Glaucoma in Dogs

Dog getting an eye exam.

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Glaucoma is a disease of the eye that can be very painful and cause permanent damage to a dog's eye if not treated. Knowing how to recognize the signs and symptoms of glaucoma and the treatment options available to dogs is an important part of helping keep your pet happy and healthy.

What Is Glaucoma in Dogs?

Glaucoma is painful disease that occurs when the pressure inside a dog's eye is too high. Normal intraocular pressure (IOP) is betwen 10 and 25 mm Hg but dogs with glaucoma have eye pressure exceeeding 25 mm Hg. If the pressure within an eye stays over 25 for an extended period of time it can cause permanent damage to the optic nerve at the back of the eye. If the optic nerve is damaged then permanent blindness can occur.

Symptoms of Glaucoma in Dogs

Dogs that have glaucoma are living in constant discomfort and even pain due to the high pressure in their eyes. Because of this pain, a dog may paw at its eye or rub it on the ground in an attempt to make it feel better. It may also hold an eye with glaucoma shut or excessively blink because of the discomfort.

Signs of Glaucoma in Dogs

  • Pawing at an eye
  • Rubbing an eye on the ground
  • Holding an eye shut
  • Bulging eye or eyes
  • Excessive blinking
  • Redness of the eye
  • Cloudiness of the eye
  • Bumping into things
  • Enlarged pupil

If the glaucoma has been present for some time, a dog's eye may appear to be bulging or larger than normal like an over inflated balloon. The enlargement may also cause issues with blood flow and cause excessive redness or inflammation on the part of the eye that normally appears white. In addition to the eye itself being enlarged, the black pupil in the center of the eye is sometimes dilated or enlarged due to glaucoma.

Glaucoma is also often seen along with other problems with the eye. Cataracts can actually cause glaucoma so if a dog has the classic cloudiness to the eye that is indicative of a cataract glaucoma may also be present or can occur. This is why it is always important to monitor chronic conditions so you can ensure no further complications arise as a result.

Finally, with glaucoma and cataracts blindness can result. Blind dogs may be used to their surroundings and do just fine at home but when you take them out of their homes you will see them bumping into things. This is due to them being unable to see the objects in front of them.

Causes of Glaucoma in Dogs

There are several ways glaucoma can occur in dogs and some are more common causes than others.

  • Cataracts: The reason why dogs can develop glaucoma alongside cataracts is due to the slipping of the lens in the eye. This movement of the lens can cause fluid in the eye to be unable to drain and build up in the eye resulting in an increase in eye pressure.
  • Eye Inflammation: Eye issues that cause inflammation in the eye such as uveitis and infections can cause fluid drainage issues and result in glaucoma.
  • Eye Tumors: Tumors inside the eye can cause an increase in eye pressure.
  • Eye Injury: An injury to the eye can cause the lens to move, inflammation, or debris to block the normal drainage in the eye.

Diagnosing Glaucoma in Dogs

After a full physical examination and discussion of the symptoms you are seeing in your dog, a veterinarian will utilize a special instrument called a tonometer. In order to use this instrument your dog's eye will fist be numbed using eyedrops. Once the eye surface is numb your veterinarian will then gently tap the tonometer onto the surface of the eye in order to get a pressure reading on the instrument. If the tonometer reads over 25 mm Hg then glaucoma may be diagnosed. The higher the pressure is within the eye the more pain a dog is typically in.

Treatment

Eye medications are typically used to lower the pressure in the eye. If the pressure is not able to be controlled with medications then surgery to remove the eye is done in order to relieve your dog of the chronic pain from the high pressure.

How to Prevent Glaucoma in Dogs

Regular physical examinations will help prevent a dog from developing glaucoma because your veterinarian will often notice concerning changes that can lead to glaucoma. Overall, keeping your dog healthy and avoiding things that increase the chances of diabetes are important things to do to help prevent glaucoma among other problems.