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DISEASES OF THE EYE LIDS
Blepharitis is inflammation and often, infection of the eyelids and may involve one or both eyes. Bacteria, fungi, parasites, allergies and trauma can all cause this condition. Most dogs show signs of swollen and thickened eyelids, loss of hair on the lids and redness around the area. In advanced cases, crusting and exudates may be present and conjunctivitis or keratitis may occur at the same time. Diagnosis is based on history, physical exam, skin scraping, cytology and cultures of exudates. ((Blepharitis))
TREATMENT OF BLEPHARITIS
Treatment of blepharitis centers on elimination of the primary cause. Bacterial infections are often Staphylococcus infections, so strong oral antibiotics are needed. Topical drops are used if conjunctival or corneal irritation is occurring. Prednisolone or triamcinolone are often used in cases of allergic blepharitis and may be used short term to relieve swelling of the lids. Parasitic diseases are treated based on the parasite present while fungal infections are treated with antifungal drugs and topical creams. Chronic cases have been treated using what is called a "staph lysate", a product designed to stimulate the body to better fight off the usual type of infection.
TRICHIASIS/DISTICHIASIS
Trichiasis occurs when eyelashes or other normally placed hairs curl towards the surface of the eye and cause irritation of the corneal surfaces. Distichiasis occurs when eyelashes grow abnormally from a gland in the eyelids called the tarsal gland. This allows the lashes to grow directly towards the surface of the cornea.
Trichiasis occurs most often in toy breeds with long hairs around the eyes, in pug-nosed dogs with prominent nasal folds (skin which rubs near or on the eye) and when dogs have entropion. Distichiasis occurs most often in Poodles and Cocker Spaniels and occasionally in other breeds. It is considered a genetic problem or defect. ((Trichiasis/Distichiasis))
The clinical signs of these diseases involve chronic irritation to the eye. Pain is present, an increase in tearing occurs and the cornea may become cloudy or blackened if the irritation is severe enough or goes on long enough, causing keratitis or corneal ulceration. Diagnosis is based on the symptoms and physical examination.
TREATMENT OF TRICHIASIS AND DISTICHIASIS
For simple cases of trichiasis, epilation of the hairs, preferably using electrolysis, works well but can not guarantee that the hair will not regrow. Cryoepilation, freezing the follicles, works well and may be more permanent. For distichiasis, your veterinarian may surgically remove part of the eyelid that contains the misplaced follicles; a procedure called eyelid splitting. Here too, lashes may still regrow. Dogs with prominent nasal folds and entropion need to be treated for those problems directly.
Dogs with very short noses, especially the toy breeds like the Pekingese and Pug can have large folds of skin between the nose and eyes called nasal folds. The skin and hair will rub against the surface of the eyes causing tearing and, in prolonged cases, keratitis and corneal ulceration. Diagnosis is based on physical examination and the clinical signs present. ((Nasal Fold))
TREATMENT OF PROMINENT NASAL FOLDS
No treatment is needed unless irritation and damage to the eyes is occurring. In these cases, irritation and corneal changes can be treated with antibiotic and steroid drops (unless ulcers are present); surgical removal of the nasal fold will generally solve the problem.
Entropion occurs when the eyelids and therefore, the lashes are turned in towards the cornea. The condition is usually inherited and most often seen in the Shar-pei, Chow Chows and Rottweilers but other breeds can be affected. Some dogs may have symptoms as soon as the eyes open but more often the inversion becomes worse as the skin and lids develop.
Clinical signs will depend upon how severe the entropion, or how many lashes are contacting the corneal surface. Tearing, pain, exposure of the third eyelid (a pain response) and keeping the eye more closed will all occur. In advanced cases, conjunctivitis and keratitis will occur. If allowed to persist, permanent damage to the cornea will lead to blindness due to corneal pigmentation and corneal ulceration may badly damage the eye. Diagnosis is based on physical examination. ((Entropion))
TREATMENT FOR ENTROPION
In young dogs, a procedure known as "eye tacking" is employed. Sutures are placed in affected lids to reposition the lid margin in an everted manner. Sutures are left in 7-10 days, then removed. Some dogs can be re-sutured several times if unsuccessful. If this fails to train the lids to lie where they should, surgical correction will be needed.
Surgical correction amounts to removing some portion of excess skin and suturing the margins leading to lid reposition. A type of plastic surgery, many different techniques exist, are beyond the scope of this program. The technique chosen should best suit the entropion present, but the experience of the surgeon is most important in producing the most functional and cosmetic results.
DISEASES OF THE THIRD EYELID
PROTRUSION OF THE THIRD EYELID
Sometimes, the third eyelid may appear to have slid out and covered part of the eye. This may occur when the dog has lost weight, is dehydrated, has ocular pain, a small eyeball, or neurological diseases affecting the muscles around the eye. This condition also occurs when animals are sedated or on certain tranquilizers. The underlying cause should be sought and corrected; the third eyelid should not be treated or removed in most all cases.
EVERSION OF THE CARTILAGE OF THE THIRD EYELID
In large breed dogs like the Great Dane and the Weimaraner, the small, T-shaped cartilage inside the third eyelid may curl or flip outward after a trauma or sometimes for no apparent reason. A simple surgical procedure can be used to correct the problem but the third eyelid should not be removed.
PROLAPSE OF THE GLAND OF THE THIRD EYELID (CHERRY EYE)
Inside the third eyelid is a paper-thin gland that contributes to making the tear film. This gland may come inside-out and swell greatly causing the clinical sign known as a "cherry eye". This is considered to be a genetic defect as the greatest percentage of dogs presenting with this problem are Cocker Spaniels, but Bulldogs, Beagles and other small breeds will sometimes appear with the condition. This usually occurs for no apparent reason, after mild trauma, or when conjunctival infections are present. Diagnosis is obvious. ((Cherry Eye))
TREATMENT OF PROLAPSE OF THE GLAND OF THE THIRD EYELID
If left untreated, the dog may have recurrent conjunctivitis and corneal damage. Removal of the prolapsed gland, which is a relatively simple procedure, is the most common method of treatment. This treatment, however, may predispose some dogs to keratoconjunctivitis sicca, which is a serious and chronic condition, so caution and consideration should be exercised.
Other techniques are available to reposition the gland into a "pocket" made by the surgeon, or to push the gland back into place, holding it there with sutures. While these procedures may be more involved and costly, long term usefulness of the gland and the lessened chance of compilations may be well worthwhile.
DISEASES OF THE CONJUNCTIVA
Conjunctivitis, the inflammation of the conjunctival membranes of the eye, is common in dogs. This may involve one or both eyes and be acute or chronic in nature. Clinical signs include the eye(s) appearing red and injected, there may be swelling to the conjunctiva and a discharge ranging from clear and thin to thick and green/yellow will be present. The eyes may be painful with the dog keeping the eye partially closed and exudates may form crusts around the eyelids.
There are many causes of conjunctivitis including dust, pollen, infections and allergies. Conjunctivitis may also occur secondary to trichiasis, tumors, "Cherry Eye", entropion and due to loss of tear production in cases of keratoconjunctivitis sicca. Foreign objects such as foxtails may also lodge in the eye and cause irritation. Outwardly, many cases appear similar no matter what the cause. Diagnosis is based on the history and physical exam of the eye, cultures, conjunctival cytology and schirmer tear testing to measure tear production.
FOLLICULAR CONJUNCTIVITIS can occur when lymph follicles located in the conjunctiva become stimulated and enlarged. Sometimes the follicles may persist even after the initiating cause has been removed and cured. Follicles also exist on the third eyelid and these too may become grossly enlarged. This is known as folliculitis of the third eyelid. Usually, folliculitis will occur after prolonged stimulation, as in a prolonged infection, although allergic reactions can quickly stimulate the follicles to enlarge.
Clinical signs include those of conjunctivitis, plus a rough, cobble-stone appearance to the conjunctiva and/or third eyelid, a thick mucoid discharge and all membranes may appear more reddened than in simple cases of conjunctivitis. Diagnosis is based on these clinical signs, cultures and cytology of conjunctival scrapings.
TREATMENT OF CONJUNCTIVITIS and FOLLICULAR CONJUNCTIVITIS
Determination of the cause of the disease is most important, with consideration for the duration and severity secondary. Cleaning the eye and applying antibiotic and/or steroidal drops or ointments is common; many combinations are available. Oral antibiotics such as amoxicillin, sulfa drugs, enrofloxacin or Clavamox are all used. Prednisolone or triamcinolone is used to control inflammation and treat allergic disease. Most cases of follicular conjunctivitis are treated in a similar fashion but may take longer to enact a cure.
KERATOCONJUNCTIVITIS SICCA (DRY EYE, KCS)
Also known as KCS, dry eye is a chronic eye disease resulting from a decrease or loss in tear production in the eye. While the cause in most cases will be unknown, immune mediated disease, neurologic conditions, trauma, infections, drugs, toxins and other systemic diseases have all been implicated. The problem seems most common in Cocker Spaniels, West Highland White Terriers, Lhasa apsos and Bulldogs. ((KCS))
The signs of the problem will include a thick, yellow/green mucus discharge, pain, conjunctivitis and corneal changes due to keratitis, including whitening or black scaring of the cornea. In some dogs, the eye may appear grossly dry, but this alone is not diagnostic, as some infections will inhibit tear production. Diagnosis is based on the history, clinical signs and performing a schirmer tear test. Dogs producing less than 5mm tears in 1 minute of testing have KCS. Dogs producing over 9mm of tears in the same time are generally normal. Repeated tests may also be needed.
TREATMENT OF KERATOCONJUNCTIVITIS SICCA
While a few dogs will recover completely from KCS, most will need lifetime therapy. Solutions to moisten the eye, stimulate natural tear production and control infection are all-important considerations. Your veterinarian may use artificial tears, a special KCS solution that will be customized for your dog or cyclosporine drops/ointment. It is also possible to transplant a salivary duct into the eye, the saliva then acting as tears. This surgery will usually need to be done by a specialist and can be complicated by excess tearing or mineral plaques forming on the cornea.
DISEASES OF THE TEAR DUCTS
Dacryocystitis is inflammation (and often infection) of the tear ducts and tear sac of the eye. Clinical signs include a thick yellow/green discharge, signs of mild conjunctivitis and increased tear production. Outwardly, this may be confused with KCS; tear production, however, will be normal in these patients. Dogs with severe conjunctivitis will also present, however, in a similar fashion. Diagnosis is based on clinical signs, a normal tear test, cultures, cytology and flushing of the tear sac and ducts under anesthesia.
TREATMENT OF DACRYOCYSTITIS
Treatment and diagnosis may go hand in hand. As flushing of the sacs and ducts will prove the diagnosis in suspected cases, flushing of the ducts with saline and antiseptic solutions is the first step in treatment. Topical antibiotic/steroidal drops and oral medications are also needed. In some cases, usually those where damage has occurred to the ducts, surgery to reopen them is needed. This will involve passing a catheter through the ducts from the eye into the opening in the nose, leaving that catheter in place for 2 weeks or more.
EPIPHORA (INCREASED TEARS)
An increase in tear production by itself is not a disease, but most often a symptom. Some dogs may be born with or acquire, due to disease, a blockage in their tear ducts. This causes normal tear production to flow over the corner of the eye. In many dogs, the tears will turn a brown-red color as enzymes as the tears oxidize. Other causes include infections, foreign objects, hair in the eyes, dust and allergies. There are also rare cases where an eye increases its tear production. Elimination of the primary cause will generally solve the problem except in cases of small tear ducts where surgery or flushing of the ducts may be needed.
DISEASES OF THE CORNEA
Keratitis is inflammation of the cornea, the clear layer at the very front of the eyeball. There are several various presentations ranging from very superficial to deep to ulcerated. When the cornea is being damaged certain signs will occur: a loss of transparency, usually causing the cornea to whiten or look cloudy; pigmentation which is like scar tissue that will appear white or black; vascularization, seen as tiny blood vessels migrating into the cornea; circumcorneal injection which is inflammation and blood vessels appearing where the cornea (clear) meets the sclera (white); pain as noted by the eye being partially shut; and increased tear production.
Diagnosis of keratitis is based on clinical signs, ophthalmic exam, cytology, cultures and pressure tests of the eye. Many times corneal disease is an extension of some other process or secondary to infections and mechanical irritants so identification and elimination of these is very important. With this information in mind, the sub-classifications of Keratitis can be explored:
This is a common disease of German Shepherd dogs and their crosses although other breeds can have the condition. Small white opacities appear on the surface of the cornea, often in both eyes and will slowly enlarge and become more opaque. Changes deep in the cornea as well as the third eyelid may occur in time. Sometimes chronic irritation may produce a similar lesion, but these tend to resolve and not recur when treated. Diagnosis is based on direct examination. ((Pannus))
INFECTIOUS CANINE HEPATITIS CHANGES (BLUE EYE)
A reaction may occur in dogs, either after receiving vaccination for or after recovery from infectious canine hepatitis (Adenovirus-I). Most often one cornea will turn a cloudy, blue-white color due to edema (swelling). Vaccination with Adenovirus-II will help prevent such a reaction. Diagnosis is based on history and direct examination. ((Blue Eye))
Pigmentation of the cornea is common after prolonged irritation. It is seen more often in dogs with bulging eyes such as the Pekingese and the Boston Terrier. External irritants, KCS, trichiasis/distichiasis, entropion, corneal injuries, pannus and chronic infections of the eye may all produce this result. Diagnosis is by direct exam, cultures, fluorescein staining, Schirmer tear testing and cytology. ((Pigmentary Keratitis)) ((Nasal Fold))
While the causes of superficial keratitis may be uncertain, immune mediated disease, viruses, abnormal tear production, extension of generalized conjunctivitis and damage from all the previously mentioned irritants can all lead to this problem. Clinical signs will vary greatly and depend on initiating causes. These causes include the following: a loss of transparency, usually causing the cornea to whiten or look cloudy; pigmentation, vascularization, seen as tiny blood vessels migrating onto and into the cornea; circumcorneal injection which is inflammation and blood vessels appearing where the cornea (clear) meets the sclera (white); and pain as noted by the eye being partially shut and increased tears being formed. ((Superficial Keratitis))
DEEP KERATITIS (INTERSTITIAL KERATITIS)
Deeper, more extensive cases of keratitis often are extensions of superficial infection, systemic disease, corneal injuries and secondary to anterior uveitis and glaucoma. Most cases will exhibit heavy loss of transparency, heavy vascularization of the cornea, changes to the iris and possibly the collection of material behind the cornea in the anterior chamber. Diagnosis is based on the history and these clinical signs. Scar tissue formation on the cornea may occur if the initiating cause is not treated and cured.
TREATMENT OF KERATITIS
GERMAN SHEPHERD PANNUS is best treated early with a steroidal ophthalmic drop and/or cyclosporine. More advanced cases are treated with subconjunctival injections of long-lasting steroids as well as the topical therapy. Radiation and surgery have been employed in advanced cases with the care of a specialist. If left untreated or if response to treatment is poor, complete blindness can occur.
INFECTIOUS CANINE HEPATITIS CHANGES (BLUE EYE)
Without treatment, some cases will resolve on their own in 2-4 weeks. Treatment will, however, speed healing and reduce the opportunity for complications and more advanced disease to occur. Topical atropine drops or ointment, antibiotics orally and topical and oral prednisolone are used together to resolve the problem.
PIGMENTARY KERATITIS
Removal of the cause of the keratitis and direct treatment of any infection present is most important. The use of topical steroids should bring dissolution of superficial pigments within 30-45 days. Deeper, more advanced cases can have permanent pigmentation that may be controllable with topical medication, but more often, may necessitate radiation or surgical treatment, including corneal transplantation to restore vision.
SUPERFICIAL KERATITIS
Depending on the actual cause, if it can be determined, there are various medications used to treat this condition. As before, removal of the initial cause is most important. Topical antibiotic and steroidal drops or ointments are often used. Oral antibiotics and steroids may also be needed. Cyclosporine and atropine drops are used in more severe cases.
DEEP KERATITIS
Also called interstitial keratitis because the inflammation runs throughout most of the cornea, deep keratitis causes more marked changes in the cornea. Again, removal of the initial cause is most important. Topical antibiotic and steroidal drops or ointments are often used. Oral antibiotics and steroids may also be needed. Atropine drops should be used to reduce pain and dilate the pupil. Treatment may be needed for several weeks.
Ulceration of the cornea involves a loss of integrity to the corneal surface and a hole forming therein. Ulcers can occur directly from trauma such as cat scratches or puncture wounds, or secondary to infections, chemicals, chronic irritation and other systemic and eye diseases.
Ulcers are extremely painful, with most dogs keeping the eye partially or completely shut. Eyes will tear excessively and the discharge may turn thick and greenish. Signs of conjunctivitis are often present along with the usual signs of keratitis, plus the obvious variation in the contour of the corneal surface. The ulcer, however, in mild cases may be small and go unnoticed by the dog owner. ((Corneal Ulcer))
Diagnosis is based on history and physical examination and your veterinarian performing a fluorescein dye test that will easily pinpoint and evaluate any ulcer present by using a wood's light. (Blacklight) Cultures and corneal cytology should also be performed to help direct the best possible treatment.
TREATMENT OF CORNEAL ULCERATION
Corneal ulcers can range from very small and punctate to large and erosive, even eroding clear through the cornea and causing the eye to rupture. Treatment, therefore, will always depend on the depth and severity of the ulcer(s). After removal of any initiating cause (in all cases), small, superficial ulcers often can be treated with topical medicated ointment (depending on cause), atropine to help relieve pain as needed and oral medications for infection as indicated by culture.
As a general principle, topical steroids should be avoided in all cases of corneal ulceration, as they are prone to quickly expand the problem and inhibit healing. Mild or moderately severe ulcers will be treated using a custom ulcer mixture most vets can prepare in their offices. This "Ulcer Mix" is a combination of drugs used to combat infection, relieve pain and assist healing of the cornea.
With larger, deeper ulcers, protection and support of the cornea is very important to assist healing. The use of a third eyelid flap with or without the eyelids being temporarily closed is most commonly employed. The ulcer would be cleaned and the third eyelid sutured temporarily over the eye, acting like a live a patch that nicely supports the healing process. Very deep ulcers may require that the cornea itself is sutured first, then the flap procedure performed. Other treatments include conjunctival flaps, corneal grafts or special contact lenses. ((Eye Flap Surgery))
DISEASES OF THE SCLERA
EPISCLERITIS (DIFFUSE EPISCLERITIS)
The sclera is the white part of the eye that comprises most of the eyeball itself. Episcleritis occurs when this tissue becomes generally inflamed, most commonly due to a hypersensitivity reaction. This may occur in along with cases of conjunctivitis or keratitis. ((Episcleritis))
Clinical signs include redness to the sclera including an increase in the number and size of blood vessels apparent on the surface of the globe. The cornea may become cloudy in the area where the cornea and sclera meet and later the entire cornea may become cloudy and have small blood vessels growing on the surface thereof. Usually there is no discharge unless secondary conjunctivitis also occurs. Cases usually start slowly and get worse with time. Diagnosis is based on the clinical signs and possibly blood testing.
TREATMENT OF EPISCLERITIS
Most dogs do well if the condition is caught early by giving topical steroid drops or cyclosporine. More advanced cases will also need oral cortisone or azothioprine. Some dogs will benefit from injections given directly into the conjunctiva near the eyeball. While this sounds unpleasant it can be a very effective treatment. Long-standing cases may be somewhat difficult to treat.
COLLIE EYE ANOMALY (SCLERAL ECTASIA)
Collie eye defines an abnormal development of the sclera, specifically the connective tissue forming the globe. It is quite common in Collies and to a lesser degree in Shelties and Border Collies. The outward appearance of collie eye may not be readily apparent but rather, seen on ophthalmologic examination of the eye. Many collies do have microphthalmia, but this is not considered as part of the anomaly.
The signs associated with this defect, which is genetic, include tortuous retinal blood vessels, thinning of the retina at the back of the eye, a cleft or pit in the back of the eye which may involve the optic disc (place where the optic nerve attaches), detachment of the retina and intraocular bleeding. Not all dogs have all of the changes, but rather, some combination thereof. Dogs are graded depending upon the degree of defect, Grade I being the mildest, Grade V the worst. Grades I-II do not affect vision; higher grades may. There is no treatment for this condition and affected dogs should not be bred. Diagnosis is based on ophthalmologic examination.
DISEASES OF THE ANTERIOR UVEA
The uvea is part of the inner eye lining which includes the iris which is the colored part of the eye responsible for opening and closing in response to how much light is present, the ciliary body which helps hold the lens in place and the choroid, which lies just under the retina. Anterior Uveitis, then, is inflammation of the iris and ciliary body.
Causes of anterior uveitis include trauma, infections, systemic disease and immune mediated disease including allergic reactions and autoimmune processes. Often a cause cannot be determined but in all cases should be sought. Clinical signs include reluctance to look at or be in the light, keeping the eyes more closed and increased tearing. Advanced cases will show signs of keratitis, material may collect behind the cornea in the anterior chamber and the iris will become rough, thickened and irregular, with the pupil being small.
Your veterinarian will diagnose this problem based on history and ophthalmic exam, ocular pressure measurement and blood testing including serology to investigate the possibility of systemic diseases. This disease may be confused with corneal diseases, outward infections or glaucoma.
TREATMENT OF ANTERIOR UVEITIS
Diagnosis and treatment of any primary or systemic disease is of the utmost importance. Treatment of the uveitis without cure of internal illness will invariably yield poor results. General therapy must include the use of oral steroidal and nonsteroidal anti-inflammatory medications and topical atropine. Many veterinarians will also employ oral antibiotics but these are considered to be of lesser importance in the treatment of this disease.
DISEASES OF THE LENS
A cataract implies a partial or complete loss of transparency to the lens due to opacity. Some cataracts are heritable and can develop spontaneously early in life. Some develop secondary to aging, other ocular diseases, diabetes mellitus, drugs, chemicals and poor nutrition. The clinical signs are obvious upon physical examination.
Diagnosis is based on direct examination of the eye and identification of the opacity of the lens. As cataracts develop at grossly varied rates, it is hard for most veterinarians to determine if small cataracts will become complete and if so, how fast. Dogs with rapidly developing cataracts should be screened for diabetes. Owners mistake often loss of corneal transparency for a cataract, but to be clear, cataracts occur in the lens which is behind the pupil/iris. ((Cataract))
TREATMENT OF CATARACTS
Cataracts can only be treated by surgical removal. Some veterinary ophthalmologists will also place an artificial lens after such a surgery but most dogs have relatively good vision after removal of the cataract. There is not other valuable treatment currently proven.
On occasion the lens may become detached from the internal attachments and move forward or backwards to varying degrees. Diagnosis is made by direct examination and is straightforward as long as the cornea is clear. Lens displacement can occur after trauma, spontaneously in some dogs, or secondarily in cases of glaucoma, cataracts, anterior uveitis and tumors of the eye. Treatment is to remove the displaced lens.
DISEASES OF INTERNAL EYE STRUCTURES/EYE AS A WHOLE
Glaucoma is an increase in the internal pressure in the eye, usually due to decreased outflow of the fluids produced within the eye. This failure may be primary (genetic, without some other cause), as in Cocker Spaniels, Beagles and the Samoyed, or secondary to anterior uveitis, lens displacement, trauma and tumors of the eye. Cases may present acutely or be ongoing and chronic in nature, depending on the cause.
Clinical signs include dilation of the pupil, redness to the eye, a cloudy cornea, pain as evidenced by the dog keeping the eye more closed, tearing, exposure of the third eyelid and enlargement of the eye followed by blindness in later cases. Pain may also lessen as the disease progresses. Diagnosis is based on history, clinical signs and examination, including measurement of intraocular pressure. ((Glaucoma))
TREATMENT OF GLAUCOMA
Acute glaucoma is considered a medical emergency and should be treated as quickly as possible. The use of steroids and intravenous mannitol to reduce intraocular pressure is important, followed by the use of drugs such as methazolamide, acetazolamide and pilocarpine to reduce the inflow of and increase the outflow of ocular fluid. Special procedures such as the use of liquid nitrogen freezing or laser surgery can be employed by specialists to correct the basic functional defects within the eye. Early aggressive treatment is a must if vision is to be preserved.
In cases of chronic glaucoma where vision is poor or has been lost, treatment may be useful to prevent further expansion of the eye and minimize pain. Many authors advise enucleation of the eye to permanently relieve pain and the suffering of the dog. Drugs and other specialty surgical procedures have also been used to stabilize glaucomatous eyes but the cost and variable results make most less desirable than enucleation.
While some dogs may be born blind, blindness secondary to other problems is seen far more commonly. Diseases causing corneal opacity such as keratitis and anterior uveitis, cataracts and glaucoma all cause blindness. Congenital and/or genetic defects of the eye, neurologic diseases, traumatic injury of the eye and head trauma are other possible causes.
It is the retina, the lining in the back of the eye that is the final light receptor. The retina transmits the image to the brain via the optic nerve where it is interpreted by the brain. Congenital defects of the retina, abnormal retinal development, inflammatory diseases which involve the retina, retinal degeneration and retinal detachment secondary to trauma will all lead to blindness in the dog. Neurologic diseases that alter brain function, such as stroke, will also lead to blindness although the eyes would be otherwise perfect and functional. Besides blindness, other clinical signs may not be exist unless there is systemic or some other primary disease is present.
These complex and variable conditions are beyond the scope of this program, but fortunately are relatively rare. Diagnosis by your primary care veterinarian with assistance from an eye specialist is the best way to deal with these problems. Dogs with permanent blindness often do very well as long as kept in a stable and confined environment. Their other senses are far more important and sensitive, so loss of vision is not as devastating to dogs as it would be in people.
Also known as proptosis of the globe, a prolapse of the eye occurs when the eye moves out of the socket. It is common in toy breeds and dogs with very short noses and big eyes like Pugs and Pekes. Most often head trauma and dogfights are responsible for this type of injury. It is considered an ocular emergency and immediate medical attention should be sought. ((Prolapsed Eye))
TREATMENT OF PROLAPSE OF THE EYE
The eye should be cleaned and free from debris. If the eyeball has not ruptured, it should be replaced into the socket. Under anesthesia, your veterinarian will clean and lubricate the globe and then manipulate it carefully into the socket. The eyelid will be sutured closed to hold the eye in place during the healing period and some veterinarians will try a wrap over the head and eye. Antibiotics orally will be used to prevent infection. Some dogs will not retain their vision, but the eye will outwardly appear normal and be cosmetic. If the eyeball ruptures, your doctor will need to remove the entire eye
MICROPHTHALMOS AND PHTHISIS BULBI (SMALL EYE)
Small eyes, called microphthalmos, can be congenital in young puppies and the eye may or may not be functional. This is generally not painful but there is no treatment for the condition. Phthisis bulbi is a small, shrunken and scarified eye that occurs secondary to severe trauma, glaucoma or infection. Enucleation may be needed in some cases.
