The Eyes Have It
When I took ophthalmology rotation in veterinary school, I was determined that I would never want to work on eye problems, as they made me extremely nervous. One wrong move, and a pet could be blinded for life. Since that time, I've actually come to really enjoy working with eye disease. The list below is by no means all-inclusive, but will give you an idea of some of the many problems that can occur.
- KCS, Dry Eye, or Keratoconjunctivitis sicca - This malady is commonly caused by inflammation in the eye causing the tear glands to decrease tear production. Diets high in moisture that help moisturize and drain mucous can be extremely beneficial. Commonly used medications include tacrolimus and cyclosporine. I recommend having them compounded in MCT oil rather than corn oil. Genteal and Refresh moisturizing drops, available over the counter at any drugstore, are very helpful. Eyes must be treated multiple times daily, generally for life. Symptoms include redness, mucoid discharge, squinting, rubbing, and possibly ulcers or infection.
- Corneal ulcers, scratches, or abrasions - damage to the cornea can occur secondary to trauma, rubbing the eye, dry eye, ingrown eyelashes, or entropion (eyelids turned in), among other causes. These are extremely painful, resulting in tearing, rubbing, squinting, and light sensitivity. These are an emergency and should be treated immediately, as the ulceration may lead to perforation of the eye and blindness. Treatment is generally topical antibiotic and anti-inflammatory therapy. Steroids should not be used here.
- Entropion - generally a congenital problem seen in certain breeds such as Shar Pei and Chow. The eyelids turn in, resulting in irritation to the cornea (front of the eye) from hair and eyelashes rubbing on the eye. Tear staining, increased tear production, and squinting are commonly seen. This can also be seen in older dogs and cats suffering muscle atrophy of the muscles behind the eyes, commonly seen in animals taking long-term steroids. Surgical correction to turn the eyelids out is the optimal solution. Moisturizing drops like Genteal and Refresh will be helpful.
- Ectropion - generally a congenital problem seen in Cocker spaniels and hound breeds. The eyelids appear droopy, revealing large pockets under the eyes that may become red and irritated. Secondary infections are common. Surgical correction will generally be the most effective treatment.
- Cherry eye - the eye of the dog and cat has three eyelids. The third eyelid, at the corner of the eye near the nose, has a tear gland at the base of the lid. If the ligaments are not strong enough to hold the gland in place, the gland pops up into view, causing the appearance of a red "cherry" at the corner of the eye. Generally, since this is a genetic problem, the glands of both eyes will be affected eventually. Rarely, the problem will be self-limiting, but surgical repair is generally required.
- Glaucoma - increased pressure inside the eye is extremely painful and is an emergency condition. Elevated pressure will damage the optic nerve at the back of the eye, resulting in permanent blindness if not addressed immediately. Symptoms include bulging red eyes that are painful. The pupils may be dilated and the cornea may take on a bluish tinge. Treatment includes drops to decrease pressure, possibly oral medications or IV drugs to rapidly lower the pressure. Eyes that do not respond to therapy generally require removal due to intractable pain.
- Cataracts - these appear as a white opaque filling of the lens in the center of the eye. They block transmission of light and cause blindness. Generally they are seen as an old-age disease, but can be congenital or secondary to diabetes mellitus. Surgery for cataract removal may be an option.
- PRA or Progressive Retinal Atrophy - this non-painful, progressively deterioration is common in certain breeds such as Cocker Spaniels, Border Collies, Irish Setters, Norwegian Elkhounds, Schnauzers, Poodles, Mastiffs, Samoyeds, and Huskies, but can be found in any breed. Antioxidant supplements given early in the course of the disease are the best defense. Early symptoms include decreased vision, particularly at night, and possibly increase light reflection from the eye (yellow eye seen when taking pictures).
- SARDS or Sudden Acquired Retinal Degeneration Syndrome - In addition to being untreatable, the cause of SARDS is unknown. Thought to be an autoimmune disease, this causes sudden, complete, irreversible blindness. Early symptoms may include increased thirst, hunger, and urination (all symptoms that may go along with an inflammatory condition causing internal heat in the body). Corticosteroids, nutritional supplements, melatonin and/or doxycycline have not improved vision in response to therapy.
- Distichiasis and Trichiasis - basically eyelashes growing in the wrong direction and places they should not be growing, rubbing on the eye, causing increased tearing, tear staining, squinting, pain, and possible ulceration. Surgical removal of the offending lashes solves the problem.
From a TCVM perspective (Traditional Chinese Veterinary Medicine), the eyes are the window of the liver. If in doubt, treat the liver. Dark leafy greens like kale, spinach, chard, mustard greens, dandelion greens, broccoli, and asparagus are wonderful for liver draining and support. Eggs and sardines are good blood tonics for the liver. Like feeds like, so addition of liver up to 5% of the diet is recommended.