Recognizing Vision Problems in Your Pet

October 2, 2020

Your pet’s eyes are an important part of her sensory system. Keep them in tip-top shape by immediately recognizing problems that could interfere with vision. The following signs warrant an immediate appointment with your veterinarian the board-certified veterinary ophthalmologist at the Animal Eye Center of New Jersey:

  • Redness
  • Cloudiness
  • Squinting
  • Ocular discharge
  • Pawing at the eye
  • An eye that appears larger than normal
  • Vision loss (trouble navigating, bumping into objects, not catching treats, etc.)

Animals can be affected by the same eye problems as their human owners. Our ophthalmologists diagnose ocular conditions such as corneal ulcers, dry eye, cataracts, and glaucoma in pets.

Corneal ulcers

Light rays enter the front of the eye through the clear cornea, which is subject to traumatic injuries, such as scratches, chemical burns, and punctures, because it is the most exposed part of the eye. The cornea’s dense accumulation of pain receptors—a unique quality designed to protect vision—make corneal ulcers extremely painful. Signs include redness, squinting, watery discharge, and light sensitivity.

Diagnosing a corneal ulcer involves staining the cornea with a dye that will adhere to damaged tissue. Treatment options for an ulcer depend on its severity.

Dry eye

Keratoconjunctivitis sicca (KCS), or dry eye, is caused by insufficient tear production. Most cases are caused by an immune-mediated infiltration of the tear glands for an unknown reason. Dry eye is seen commonly in certain breeds, including:

  • Cocker spaniels
  • Bulldogs
  • West Highland white terriers
  • Lhasa apsos
  • Shih tzus

KCS has also been linked to particular medications.

Dogs with dry eye have a chronic mucous discharge, redness, discomfort, and may have vision deficits. Cases that are not well-managed lead to chronic irritation and corneal scarring, which eventually interferes with vision.
KCS can be diagnosed by measuring the amount of tears made by your pet’s eye. Treatment is life-long, and includes medications used to encourage tear production and add moisture to the eye.


A cataract is cloudiness of the lens, which is a normally transparent structure suspended in the eye’s center that bends light rays and focuses them on the retina. Cataracts can form for a variety of reasons, although the most common cause is genetic or inherited. Susceptible dog breeds include:

  • American cocker spaniels
  • Havanese
  • Miniature schnauzers
  • Boston terriers
  • Bichon frise
  • Silky terriers
  • Poodles

Cataracts are also a common complication of diabetes

A cataract often starts as a small spot on the lens that does not significantly affect vision. Over time, however, a cataract can expand, affecting more of the lens and interfering with vision.

A cataract can be diagnosed during a thorough ocular exam. Once a cataract interferes with vision, the only effective treatment is surgery performed by a veterinary ophthalmologist. During the procedure, the lens capsule is incised, the lens material is broken up and removed, and an artificial lens is implanted using the same equipment and techniques utilized in human cataract surgery.


The front of the eye is filled with a fluid called aqueous humor that is constantly produced, circulates through the eye, and drains away through a duct system. The fluid accumulates within the eye if drainage is interrupted or slowed, which raises the intraocular pressure. Increased pressure on the retina and optic nerve, can quickly lead to blindness.

Glaucoma may cause the eye to appear larger in chronic cases, but in acute cases the eye is frequently normal in size, but may be red and cloudy. However, all cases of redness, cloudiness, squinting, or ocular discomfort should be evaluated immediately, because glaucoma frequently causes permanent vision loss. A veterinarian can easily measure intraocular pressure and determine whether glaucoma is present with an instrument called a tonometer.

Glaucoma treatment includes lifelong management with medications to control ocular pressure. Unfortunately, glaucoma often leads to blindness, even in pets who are treated. Watch for the following signs that your pet may be losing her sight:

  • Bumping into things in the environment
  • Decreased activity
  • Startling easily
  • Trouble finding food bowls or toys
  • Difficulty locating a treat held in front of her

Your pet’s vision is important to her quality of life. All concerns related to her eyes should be checked out immediately to minimize the risk of vision loss.