A good general rule for all dog owners to follow is to have any eye or adjacent tissue dysfunction evaluated by a Veterinarian without delay. Animals suffer from eye problems that are similar to those which affect humans. These problems include cataracts, red eyes, glaucoma, tumors of the eye, eyelid defects, inflammation of the eye, dry eye, retinal degeneration, ocular (eye) discharge and many others.
1. Red Eyes: Pets eyes become reddened when blood vessels of the conjunctiva (the pink lining of the eyeball and eyelids), sclera (white covering of the eye), or cornea (clear surface of the eye) become enlarged or more numerous. It may also occur with inflammation of the structures inside the eye, with glaucoma (high pressure within the eye) or with certain diseases of the orbit (eye socket). The eyes can become irritated due to allergies induced by pollens, grasses, etc., or from infections caused by viruses, bacteria, or fungi. Red eyes is common in both cats and dogs. Either one or both eyes can become red, depending upon the cause of the problem. It is recommended to keep your pets eyes clean, eliminating the cause of the conjunctivitis with appropriate medication. Red eye is a non-specific sign of inflammation or infection.
What are the symptoms?
- Redness of the eye or structures around the eye
- Possible decrease in vision or blindness
- Possible cloudiness of the eye
- Tearing or discharge from the eye
- Possible systemic signs if the redness is associated with some sort of illness
- Squinting, increased blinking, holding the eye closed
- Pawing or rubbing at the eye
2. Cherry Eyes: The medical term for 'cherry eye' is nictitans gland prolapse, or prolapse of the gland of the third eyelid. Unlike people, dogs have a 'third eyelid' that contains a tear gland and is located in the corner of each eye. Under normal circumstances, this gland is not visible and aids in the production of tears. For some reason, which is not completely understood, the gland of the third eyelid prolapses or comes out of its normal position and swells creating the condition known as cherry eye.
What are the symptoms?
- Oval pink or red mass protruding from the corner of the eye closest to the nose
- Watery or thick discharge from the eye
- Redness to the conjunctiva (lining of the eyelid)
- Occasional pawing at the eye
- A weakness of the ligamentous attachment of the gland of the third eyelid is believed to be the most common cause in the dog.
- Although this weakness may be a heritable condition, the inheritance pattern is unknown.
- Prolapse of the gland may occur secondary to inflammation.
- Idiopathic (unknown cause) forms also exist.
3. Dry Eyes ( Keratoconjunctivitis Sicca or KCS): Keratoconjunctivitis sicca (KCS) is a Latin medical term used to describe a condition of decreased tear production. The term technically means “inflammation of the cornea and conjunctiva from drying.” When the watery part of the tears is not produced in adequate amounts, the eye becomes chronically inflamed, and scarring and pigmentation of the cornea may lead to a decrease in vision. Another commonly used term to describe this disease is “dry eye.”
What are the symptoms?
- Chronic redness of the eye
- Chronic thick, yellow-green discharge, especially in the morning
- The development of a film over the cornea
- Decreased vision in predisposed breeds
- The most common cause of KCS in dogs is an immune-mediated destruction of the tear glands. This cause occurs in female dogs more often than male dogs, and is more common certain breeds, such as the American cocker spaniel, English bulldog, Lhasa apso, and West Highland white terrier.
- Other causes of KCS include a rare side-effect of certain medications (especially sulfonamide containing drugs), removal of a prolapsed gland of the third eyelid, infections (such as canine distemper), chronic inflammation of the conjunctiva, trauma to the tear glands, and certain skin diseases and neurological disorders.
- Animals with low thyroid hormone output (hypothyroidism) are also predisposed to KCS.
4. Ocular (Eye) Discharge: Ocular discharge is a common sign of eye disease. Abnormal discharge may develop suddenly or gradually. The discharge may be watery, mucoid (gray, ropy), mucopurulent (yellow-green, thickened) or bloody. In general, the more discharge present, the more serious the disease.
- Obstruction of tear drainage due to abnormal tear ducts or tear duct openings
- Excessive production of tears by the tear glands from irritation or inflammation of the surface structures of the eye, or from pain in or around the eye. Examples include:
- Keratitis (inflammation of the cornea)
- Defects or abnormalities in the eyelids
- Corneal ulcers
- Lens luxation (displacement)
- Uveitis (inflammation of the iris and blood vessel layers within the eye)
- Keratoconjunctivitis sicca or dry eye syndrome
- Infection on the surface of the eye, or in association with generalized infections or illness
Veterinary care includes diagnostic tests and subsequent treatment recommendations. Several tests are required to diagnose the condition of the eyes and to define subsequent treatment. Do not delay in bringing your pet to your Veterinarian for examination as some causes of excessive ocular discharge are potentially vision threatening and require immediate medical attention. The underlying cause for the problem must be properly addressed.
Eye drops or ointments are usually the drugs of choice. Eye drops are watery solutions that must be applied every few hours, while ointments last longer and are usually only applied two to three times per day. In severe cases, oral antibiotics are used in addition to the topical preparations.Many eye ointments containing hydrocortisones and antibiotics are available and are frequently used when the exact cause of the problem is unknown. It is important, however, not to use hydrocortisone-containing agents if a corneal ulcer is present. Hydrocortisone, although great at minimizing eye inflammation, may actually hinder the healing of or worsen an ulcerated cornea.