Eye Problems in Dogs

Eye Problems in Dogs… Don't Be Fooled

by T. J. Dunn, Jr. DVM

Almost daily every animal hospital receives a call about canine eye problems; and the diversity of concern expressed by the dog’s caretaker runs a wide spectrum. There are times when veterinarians will check a frantic and anxious client’s dog only to discover an insignificant soreness in the dog’s supporting tissues around the eye (called conjunctiva). The very next “eye case” may be an advanced corneal ulcer that has allowed internal contents of the eye to actually protrude through the corneal surface! And that client might calmly state, “It’s been like that for two weeks but we though it would clear up”.

Fortunately in most veterinary practices the entire staff has been directed to prioritize all calls that express concern about a potential ocular difficulty. The reason for expediting the evaluation of any case relating to eye difficulties is that there is no way for verbal description to convey the true nature or severity of the problem. Seemingly innocent conditions can fool you… and result in an ocular emergency rather rapidly. These cases simply must be seen right away.

Let’s take the “squinting dog” as an example. Surely any dog might develop a mild irritation in an eye and squint for a few moments, and extra tear production would be expected, too. But without direct examination of the eye and attendant structures, no one (not even a Specialist in Veterinary Ophthalmology) would know if the squinting is due to a tiny scratch on the cornea, a cinder hiding beneath the third eyelid or a penetrating wound from a carelessly aimed BB gun! And one of the very first signs of systemic diseases such as Blastomycosis or cancer could be an innocent looking squint.

I asked a Specialist in Veterinary Ophthalmology, Deborah S. Friedman, D.V.M., of Animal Eye Care, in Fremont, California what the most common eye condition might be that could potentially fool the dog’s caretaker into delaying an eye exam. Her reply was… “Glaucoma comes immediately to mind. In many cases owners delay treatment of glaucoma until it is far too late. If the intraocular pressure in the eye is elevated for more than 24-48 hours, permanent damage is the usual outcome and this usually means blindness and sometimes loss of the eye. Signs of glaucoma can be very subtle at first and could include a dilated pupil that responds poorly or not at all to light, a cloudy cornea, a red appearance to the eye, and poor vision. Glaucoma can be dangerous because many of the signs of glaucoma are similar to simple conjunctivitis.”

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. As Friedman states “In my opinion, any injury to the eye (from cat fight, thorn, foxtail, BB gun, caustic substance etc.) should be brought to the attention of a veterinarian immediately (within 12 hours if possible). With eye injuries, the sooner the specific problems are identified and treated the better the chance of saving eye function”.

During routine physical exams internal disorders are often first recognized by subtle changes in the normal appearance of eye structures. A yellowish appearance of the normally white sclera, undetected by the pet ‘s caretaker, signals to the veterinarian that there is likely to be a liver or red blood cell dysfunction. And a faint haziness in the normally transparent cornea can prompt the need to evaluate liver or pancreas function. Tumors of any of the eye structures can occur and need to be addressed at the earliest possible time in their development.

Puppies and Eye Disorders

If you are about to acquire a new pup be sure to become informed about common eye disorders for the breed of interest. For example, Friedman states “Cocker Spaniels frequently develop dry eye (see photo: Dry Eye) and glaucoma. Bichon Frise, Cocker Spaniels, Poodles, and Boston Terriers among other breeds often develop cataracts (see photo: Cataracts). If a potential owner is aware that the breed they are interested in has inherited eye problems the buyer can educate themselves about what to look for.” The more you know about your preferred breed the better your chances of obtaining a healthy dog. One commonly seen condition in pups, called entropion, is readily seen upon close inspection. This rolling inward of an eyelid will surely require surgery to eliminate the corrosive action of the lid hairs on the cornea; and potentially the condition could be passed on to any future offspring.

Patricia J. Smith, MS, D.V.M., Ph. D., Diplomate, American College of Veterinary Ophthalmologists and a colleague of Dr. Friedman at Animal Eye Care lists some common ocular problems in puppies. Become familiar with these disorders and be prepared to closely scrutinize any new pup for signs of these common difficulties:

Common Ocular Disorders In Puppies

1. Entropion: Inward folding of an eyelid where lid hairs contact the cornea (Shar Pei, Cocker Spaniel, Rottweiler, Labrador Retriever, etc.)

2. Cherry Eye: Prolapsed gland of the third eyelid. (Bulldogs, Cocker Spaniels, Poodles, etc.) (See photo: Cherry Eye)

3. Ectopic Cilia: An abnormal eyelash that grows through the conjunctiva and is usually very painful and almost always causes an ulcer. (See Photo: Corneal Ulcer)

4. Distichiasis: Abnormal position of eyelashes on a lid margin that result in irritation of the eye.

5. Dermoid: Congenital defect where haired skin is located in an abnormal place on an eye and will often irritate the cornea and can cause ulcers.

6. Cataracts: Opacity of the lens. Inherited cataracts can often appear in young dogs, in most cases a veterinarian or veterinary ophthalmologist will have to make this diagnosis; owners are often unaware of small focal cataracts. There are also late onset cataracts that may not show up until middle or older age.

7. Follicular Conjunctivitis: Itchy, reddened conjunctival tissues, tearing, squinting, often related to allergies.

8. Puppy Pyoderma or Puppy Strangles: Eyelid abscesses associated with generalized skin pustules.

9. Dry Eye (Keratoconjunctivitis sicca or KCS): Lack of or inadequate production of tears. Sometimes this can be congenital in which case it is often very serious. Pug, Lhasa Apso, Shih Tzu are some of the breeds that may be born with dry eyes.

When you visit a breeder and evaluate pups for purchase it is best to do a careful and critical evaluation of any pup’s eyes before you make that purchase decision. Bring a penlight along and shine it directly into and at an angle to each eye. There should be no specks in the cornea, the pupil should be dark, the iris should constrict when the light enters the eye, and there should be no tiny stray eyelashes directed from the lids toward the cornea (Distichiasis).

As Friedman says “Conditions that the owner may think are trivial, may in fact be the early stages of something more serious. Often dogs are stoic and do not exhibit blatant signs of pain.” So don’t be fooled by subtle eye problems… they may not be so innocent after all. Do a thorough inspection of any new pup’s eyes and associated structures before you decide to make it a part of your “family” or breeding stock. And in any dog, if ordinary first aid provides no improvement in eye discomfort within 12 hours, be sure to obtain a veterinarian’s evaluation.

Common Home Remedies Suggestions

Ordinary Eye Wash (Sterile Buffered Saline) is proper to use in a dog’s eye to clean the eye but it will not be helpful for an inflamed, sore eye. For a red, sore eye seek veterinary attention immediately. Visine should not be used. It is not therapeutic; it merely makes the eyes less red for a short time. It can be potentially harmful in some conditions. Artificial tear drops or ointments are usually not harmful and may be soothing for some dry eye conditions, but advice of a veterinarian is urged in any case.

CERF (Canine Eye Registration Foundation) is a foundation that certifies dogs to be free of inherited eye problems. A reputable breeder would have both the sire and dam “CERFed” before every breeding. CERF certification numbers are only good for one year since there are many late-onset diseases such as retinal atrophy and cataracts. If someone is buying a purebred dog of a breed with inherited eye problems, they should ask to see the CERF number and examination forms. Genetic testing is available for several of the inherited and blinding retinal atrophies. Some breeders may have this genetic information about their line if they have had the dogs DNA tested.

Veterinary attention should be sought for any of the following conditions:

• Red eye

• Painful eye (squinting, pawing, rubbing, tearing, decreased appetite)

• Tearing

• Cloudy eye

• Blood in or around eye

• Suddenly blind eye

• Dilated pupil

• Swollen eye

Severe eye trouble!  Click on the image to see this *panophthalmitis photo up close.  This patient did well after surgery and medication.

*Acute suppurative inflammation of the inner eye with necrosis of the sclera (and sometimes the cornea) and extension of the inflammation into the orbit. Pain may be severe and the globe may rupture. In endophthalmitis the globe does not rupture.