Eye diseases in dogs

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Eye diseases in dogs

Often, people are surprised by the number of different eye diseases that can affect dogs.

From cataracts and glaucoma, to structural abnormalities that interfere with tear production, there are a variety of problems to be aware of. Eye diseases in dogs range from mild to severe enough to cause blindness or even eye loss. While holistic medicine is best at prevention, and is very helpful for treating mild conditions, a severe eye problem usually needs the hammer of conventional medicine to prevent blindness, though holistic methods can help speed recovery.

Anatomical problems

1. A number of eye diseases are caused by bad anatomy. The special appearance some dogs are bred for can predispose them to specific eye diseases. Because these are caused by the way the dog is shaped, surgery is often the only answer. One example is ectropion, where a dog has excessively droopy eyelids. These dogs look hung over, with red eyes. A typical example is the Basset hound. The show standard for Bassets specifies that the lids droop, so the inside of the lower lid shows. When they droop too much, the exposed inner eyelids become inflamed and irritated. Dogs with this condition have red eyes all the time, and may have excess tear production. A mild case can be helped by soothing eye drops, but a severe case can cause so much inflammation and resulting infection that the only recourse is surgery. A type of plastic surgery lifts the lower lids so they assume a more normal position.

2. The opposite of ectropion is entropion. Breeds that have a lot of skin folds or loose skin around the eyes, such as shar peis or cocker spaniels, are especially prone to this problem. When the skin folds inward, the hair rubs on the eye. Constant rubbing not only irritates the surface of the eye, but can also eventually scratch the eye or even cause an ulcer. This can ultimately result in vision loss. Though soothing eye preparations sometimes help temporarily, surgery is the best answer. The surgeon removes some of the excess skin, which pulls the remaining skin back into a normal position.

3. More difficult to diagnose is distichiasis, where eyelashes form on the inside of the eye. A strong light and some sort of magnification may be necessary to see these small lashes. Their effect is the same as entropion, though less severe: they rub on the eyeball, causing inflammation and irritation. The offending eyelashes are plucked out, usually under anesthetic.

4. Little dogs with prominent eyes and squashed noses (pugs, lhasa apsos, shih tzus, etc.) have eyes that are more exposed to the elements. Their lids may not fully close and they may have reduced tear production. Antioxidants and homeopathic or herbal eye drops can be helpful. Eyebright (Euphrasia) is often used herbal eye drops, but it is now a threatened herb and can’t be grown in captivity. Look for a suitable alternative, such as chamomile or Ayurvedic drops.

The eye sockets of these breeds are shallow, so it is easier for an eye to actually pop out of the socket when there is a head injury (e.g., from a dog fight). If this happens, take your dog immediately to a veterinarian. The eyelids will usually be sutured shut, to help hold the eye back in while stretched and torn tissues heal.

Tear troubles

5. Sometimes, in both dogs, the tear duct is blocked. Tears will run down the face but there is not a lot of irritation in the eye. This is not a true eye disease, and can be differentiated when your veterinarian puts some dye into the eye. If the duct is open, the dye will travel with the tears down into the nose and out. If no dye appears after a few minutes, the duct is blocked. Your veterinarian can unblock it and flush it out with a cannula inserted into the tear duct. Rarely, some dogs are born without an opening in the tear duct; in that case, surgery is performed to make a small opening.

6. Dogs may develop an autoimmune disease known as keratoconjunctivitis sicca or KCS, that decreases or stops tear production. The surface of the eye may appear dull or there may be white or yellow-green mucus. Sometimes it is associated with allergies and will only be present during allergy season, but most of the time it is a year-round condition. If not treated, inflammation can cause ulcers or permanent scarring, leading to blindness. Your veterinarian will diagnose this with a Schirmer tear test, where tear production is measured by putting strips of special paper in the eye. If too few tears are produced, the tears travel only a short way along the paper. The primary treatment is cyclosporin ointment; acupuncture and antioxidants can help enhance this treatment.

Irritation, infection and inflammation

7. A foreign body in the eye will cause a lot of tears and inflammation, and often the eye will be shut tight. Foxtails are the most common foreign body, usually in dogs and can do a lot of damage by scratching the eye and causing infection. It can be difficult to remove a foxtail yourself because it is so painful that the eyelids will be tightly closed in spasm. A veterinarian has a local anesthetic that can be applied to the eye to relieve the pain and spasming, making the foxtail much easier to remove. If you suspect a foxtail, don’t wait around to see if it gets better, since the longer you wait, the more severe the damage.

8. In normal eyes, infection and inflammation have many causes. These include allergies, rubbing the eye and accidentally scratching it, wind blowing dirt into the eyes, and rough-housing with playmates. Signs of mild irritation are redness, excess tears, and rubbing the eyes. Scratches, ulcers, and increased inflammation can produce squinting and mucous, and you may see a pink structure in the corner of the eye (the third eyelid). More extreme inflammation or infection will cause yellow or green mucous as well as severe squinting or even holding the eye shut. It can result in loss of vision if not treated aggressively, and a trip to the veterinarian is in order. To determine the cause, the veterinarian will put a dye in the eye to see whether there is a scratch, abrasion or ulcer (these can be amazingly difficult to see without dye). Treatment depends on how severe the problem is.

If the irritation is mild, you can treat with antioxidants (by mouth) and soothing Ayurvedic or chamomile eye drops. If the diagnosis is allergic conjunctivitis, antioxidants, fish oil, flavonoids, Chinese herbs and probiotics can be helpful. Homeopathic Pulsatilla and Similisan #2 can also give relief.

Cataracts and glaucoma

9. Cataracts are common in older animals. They are more often seen in dogs than cats, and show up initially as a slight cloudiness in the pupil that increases over time. Cataracts progress most rapidly in animals with diabetes, and tend to be worse in small dogs than large ones. If they are bad enough, they can cause painful uveitis (inflammation of some of the internal tissues in the eyeball) and blindness. In the early stages, if not caused by diabetes, antioxidants and herbs such as Ocu-Clear from Thorne Research may be helpful. Later on, cataract surgery can be performed by a veterinary ophthalmologist.

10. In glaucoma, fluid inside the eyeball builds up and does not exit the eye as it normally should, causing increased pressure in the eye and on the retina. There are many causes. The signs are subtle, and often not easily detected except by a special medical instrument that detects eye pressure. When glaucoma gets bad enough, the eye will become enlarged and hard. At this stage, the animal is usually blind or has very impaired vision. In the early stages, acupuncture, glycine, alpha lipoic acid, Chinese herbs, and homeopathic preparations may be helpful. Later on, conventional medications are needed for complete control, to prevent blindness or the need for surgery.

Good eye health is a big part of your animal’s well being. Watching out for potential issues, and visiting the vet promptly when you’re in doubt about the cause or severity of a problem, can help ensure your dog continues to see clearly.