Cataracts and Eye Problems in Dogs

One of the most common conditions that affect a dog’s eyes are cataracts. The formation of cataracts in dogs can be caused by various things. All breeds and ages of dogs can develop cataracts but certain breeds are more susceptible to cataracts than others; among these are Cocker Spaniels, Poodles, Miniature Schnauzers, and Terriers.

Cataracts are an interference of lens fibers that obstruct sight by blocking clarity in the lens, either partially or totally. Smaller cataracts may not disrupt a dog’s vision at first, but the cataract could grow in size and density and cause a dog to lose its sight entirely if the cataract is not removed.

Cataracts that form in dogs over 6 years of age are called “senile cataracts.” When cataracts develop much earlier than this they are called “developmental cataracts.” Developmental cataracts can be hereditary or caused by trauma, infection, toxicity, or diabetes. “Inherited cataracts” are common in Standard Poodles, Afghan Hounds, Miniature Schnauzers, Old English Sheepdogs, and Welsh Springer Spaniels.

Congenital cataracts are present at birth; developmental cataracts develop early in a dog’s life; senile cataracts occur in dogs over six years of age, and inherited cataracts occur independently or in association with other visual diseases. Cataracts can also be caused by a trauma related to an auto accident or an object penetrating the eye. In trauma cases, the lens becomes damaged and a cataract may develop.

As a dog ages, eye health becomes a major concern. Over time, free radicals can cause oxidative stress on the cells of the eyes, and as a consequence, dogs have more difficulty fighting oxidative stress as they get older.

Exposure to oxygen and sunlight causes a chemical reaction in the cells, and the lens of the eyes are affected by this oxidative action because the lens acts as a light shield for the retina. Blood flow also decreases as the animal ages, resulting in nutrients being slowly depleted from the eye, causing even more stress and damage.

Dog cataracts are not a problem you might face only if you have an older dog. Cataracts can form at a fairly early age in some breeds. Afghan Hounds can develop cataracts at age 6-12 months, American Cocker Spaniels at 6 months or slightly older, German Shepherds at 8 weeks, Golden Retrievers at 6 months or later, Labrador Retrievers at 6 months or later, Siberian Huskies at 6 months or later, and the Standard Poodle at a year or later.

Cataracts are easy to identify by their white or bluish-white appearance in the pupil of the eye. If you suspect that your dog has or is developing cataracts or an eye problem, contact a veterinary ophthalmologist immediately.


Vision Problems in Dogs

Vision problems can be painful or disorienting to a dog. Eyeglasses, although sometimes prescribed for dogs, is something very few dogs can ever get used to.

Symptoms of vision problems in dogs can include the following:
* Excessive tearing or redness
* Closed or partially closed eyes most of the time
* Rubbing the eyes or face
* Cloudiness in the eyes
* Discharges from the eyes

When dogs have difficulty with their vision it’s usually the result of eye problems ranging from ingrown eyelids to corneal ulcers which are open sores on the cornea, the clear structure covering the iris (the colored part of the eye). Many eye problems in dogs can be treated with medication and surgery, and others can easily be prevented.

Eye and eyelid diseases are divided into specialized categories: hereditary, trauma, inflammatory, eye and eyelid tumors, and congenital. The difference in the anatomy of a dog’s eyes in different breeds of dogs can predispose certain breeds to eye and eyelid diseases. Giant and large breeds for example, have deep, large eyes which can predispose them to chronic conjunctivitis.

Conjunctivitis, or “dog pink-eye” is an inflammation of the mucous membranes of the eye and is the most common eye disease in all domestic animals. Dogs with allergies are often prone to developing conjunctivitis. Viruses or bacteria can also cause conjunctivitis, while allergies are a less common cause.

Conjunctivis can make your dog’s eyes inflamed, itchy, and sensitive to light. Your dog may avoid light, rub its eyes excessively, or the eyes may begin to water.

Symptoms of conjunctivitis include abnormal eye discharges limiting your dog’s ability to blink or close its eyes, and pink inflammation of the eyes. Conjunctivitis usually itches, so if your dog develops this disease, you’ll need to keep its eyes clean and eliminate the cause of the pink eye with input from your veterinarian.

Chronic superficial keratitis, another eye disease occurring primarily in German Shepherds, causes pigmentation and superficial blood vessels on the eye. It’s not very painful but it can reduce your dog’s vision if left untreated.

Keratitis also occurs in chronic cases of keratoconjunctivitis sicca (KCS). KCS occurs when there is not enough moisture in the tear film. A thick mucus discharge is usually present with this common eye disorder. Treatment for the disease involves the application of tear stimulants and anti-inflammatory drugs.

Corneal ulcers occur when your dog experiences an eye injury or gets a foreign object in its eye. The injury may become infected and require antibiotics. If a foreign object becomes stuck in your dog’s eye, surgery may be necessary to remove it. A corneal ulcer usually causes your dog’s eye to water excessively.

In the case of external eye diseases such as conjunctivitis, keratoconjunctivitis sicca (KCS) and superficial corneal ulcers, eye drops with an antibacterial agent are usually prescribed. The drops need to be administered several times a day over a period of several days for successful treatment.

There are several disadvantages to eye drops however, the most prominent one being the natural rapid removal of the eye drops from the corneal surface.

Cataracts cause the clear lenses of your dog’s eyes to become cloudy over time. This condition is usually genetic and occurs when your dog is elderly. As in humans, surgery is recommended for cataracts and the procedure has a very high success rate; about 90% of dogs who undergo cataract surgery experience complete recovery of their vision.

In-grown eyelids can be hereditary, or can occur as a result of chronic, untreated inflammation of the eyes. In this condition, the eyelids turn in, causing the eyelashes to rub against the eye. This can give your dog a large, often white corneal ulcer. You can examine your dog to see if it is suffering from in-grown eyelids by gently pulling the lid away from the eye, then letting it drop. If it curls back on itself, your dog is probably suffering from in-grown eyelids, and will need corrective surgery.

Diagnosing vision problems in dogs can be difficult. For example, if your dog’s eyes are red, it could be a symptom of an eye problem requiring treatment as simple as eye drops or as complicated as emergency eye surgery. Red eye in dogs can also be a sign of inflammatory conditions or an infectious disease. If you notice any of the symptoms of these diseases in your dog, it is best to schedule an appointment with your vet to have your dog examined professionally.