Dog corneal ulcer

Corneal ulceration is called ulcerative keratitis - this is a serious eye disease that can lead to serious consequences, up to complete blindness of the pet. This pathology is detected in both humans and dogs. But it does not matter who the patient is, the main thing is that the patient receives timely medical care. What threatens corneal ulcer in dogs and how is this disease treated?

What is ulcerative keratitis

The corneal layer is the front part of the shell of the organ of vision, which includes several layers:

• upper - epithelial, is a protective membrane of the organ of vision;
• then follows the stroma - the basis of the entire cornea;
• Dessemeth membrane (desmemetova membrane) - posterior border wall;
• the posterior epithelial layer is the corneal endothelium; it supports weak dehydration of the eyeball.

In the normal state, the cornea has a smooth, transparent, without any roughness, surface; there are no blood vessels in its layers. And since it contains a huge number of nerve roots, this area is characterized by increased sensitivity.

Corneal ulcerative lesions affect its upper epithelial layer. If we draw an analogy with skin damage, then the ulcer is a scratch, but not just the skin, but the corneal layer, and this pathology is considered more dangerous.

The condition of a sick animal suffering from an ulcer is aggravated by the fact that due to the abundance of nerve endings in the cornea, this form of keratitis is accompanied by intolerable soreness. The pain knocks the pet out of the usual rut, does not allow him to eat normally, relax, and causes insomnia. This condition quickly leads to nervous and physical exhaustion of the dog.

Against the background of damage, the epithelial layer of the eye degrades rather quickly, the organ loses reliable protection against various infectious pathogens. Ulcerative keratitis is a serious pathology, a complication of which is often a bacterial infection of the eyes and subsequent blindness.

Types of erosion and the causes of their occurrence

There are several types of ulcerative keratitis. First of all, depending on the cause, the disease can be infectious or non-infectious. The occurrence of infectious ulcers is often associated with a viral, bacterial, fungal lesion of the cornea. In addition, damage can be triggered by infection with parasites.

Such peptic ulcer disease is difficult to treat and often recurs. Most often, an infectious ulcer is caused by staphylococcus, streptococcus, Pseudomonas aeruginosa, herpes virus, coronaviruses, and Koch's bacillus. In addition, chlamydial infection can cause ulcerative keratitis in pets.

With non-infectious keratitis, the following conditions can act as factors provoking the appearance of ulcerations on the corneal layer:

• pedigree predisposition - most often eye pathologies develop in dogs with bulging eyes (brachycephalus) - Pekingese, Japanese chin, Shih Tzu, Boston Terriers, French Bulldogs, Great Danes, Labradors, etc .;
• hit of a foreign body on the cornea and third eyelid;
• a change in the position of the eyelids (inversion);
• dry eye syndrome;
• burns of the mucous membranes of the eye - chemical, thermal, ultraviolet, etc .;
• violation of the growth of eyelashes (dystrichiasis, cilia) that begin to scratch, rub the surface of the cornea;
• limbal corneal insufficiency;
• decrease in local immunity.

Also, experts distinguish superficial and deep ulcerative keratitis:

• superficial pathology - the lesion affects the epithelial layer and stroma of the cornea;
• deep pathology - ulceration spreads to all layers of the stroma. With the progression of the disease, the pathological process penetrates the thickness of the cornea, affecting the discemet membrane, which threatens with perforation of the anterior membrane of the eyeball;
• descemetocele is a condition in which complete perforation of the corneal layers occurs when through damage appears and reaches the descemet layer.

Of particular note is the chronic erosion of the cornea, in which damage does not heal for a long time. Pathology is called endolent erosion or ulcer boxers. The risk group for this pathology includes representatives of the following breeds: boxer, dachshund, spaniel, spitz, etc. Most often, the disease is diagnosed in animals older than 5 years.

The peculiarity of keratitis in this case is that the lesions may not heal for weeks, and there are no visible reasons for this, and the drugs used do not give a positive effect.

The cause of the disease lies deeply - the contact of the epithelial cells with the cells of the basement membrane fails, so normally recovering epithelial tissues cannot be fixed on the membrane, and desquamation occurs. Naturally, under such conditions, the damaged area simply has nothing to close.

Quite often, ulcerative keratitis has no pronounced signs, and the owner of the dog does not notice that his pet is sick. But over time, the disease progresses, the dog begins to feel severe pain and discomfort. At the first symptoms of the disease, the dog should be shown to the veterinarian.

Dog corneal ulcer symptoms

When is the dog owner concerned about the condition of the pet? In the acute stage, corneal erosion is accompanied by increased release of tear fluid and photophobia.

The pet makes constant attempts to rub his eyes with his paws, which further aggravates the condition of the visual organ - in this situation, injury to the damaged organ and secondary infection of existing wounds are possible. The conjunctiva turns red, spasms of the eyelids occur.

Gradually, existing sores become more noticeable, if pathology is not treated, then a perforated ulcer may occur. A complication of this condition is panophthalmitis, an acute purulent inflammatory process that affects all tissues and membranes of the visual organ or prolapse of the inner parts of the eye.

Diagnosis of corneal ulcer in dogs

In case of eye diseases in dogs, the owner is advised to contact a veterinary clinic that provides specialized services. In this case, consultation with an ophthalmologist is advisable. In addition, such hospitals have all the necessary devices and apparatuses that allow the most accurate diagnosis of pathology.

But if this is impossible, it’s still worth taking the pet to the nearest veterinary station. First of all, the doctor examines the patient, identifying violations:

• external examination allows you to evaluate whether both organs of vision are symmetrically located and deepened;
• a test for reflex ability;
• the specialist checks if pain symptoms are present.

Using an ophthalmoscope and a slit lamp, an ophthalmologist examines the eyelid, cornea and anterior chamber of the organ. This is possible if there is no severe clouding of the cornea.

The doctor in the arsenal has several specific techniques that allow you to conduct a series of tests:

1. Schirmer test - provides an opportunity to examine the process of secretion of tears in order to detect dry eye syndrome. To conduct the test, a strip of filter paper with the edge is folded and placed behind the lower eyelid. Within 5 minutes, it is saturated with tear fluid if the eye is healthy. With pathology, the paper remains completely dry.
2. The Seidel test with fluorescein is an ophthalmology technique that can detect lesions that penetrate the cornea, and it is also used as an additional way to study the activity of the lacrimal gland. The test is carried out as follows: the specialist applies a local anesthetic to the corneal surface - he buries his eyes 2-3 times. After the fluorescent solution is applied. Then the doctor with a cotton swab slightly presses on the eye, assessing the leakage from the damaged area in the light of an ultraviolet lamp. If a strip of dark color is washed out from the ulceration down onto a green background, then the sample is considered positive, and the organ is perforated. In this case, emergency microsurgical wound sealing is required.

If an erosion site is detected during diagnosis, a specialist examines the edges of the eyelids, evaluates the condition of the conjunctival sac. In the process, it is possible to detect provoking factors: ectopic eyelashes, aggressively growing hard dysthichiasis eyelashes, neoplasms, foreign components.

Corneal ulcer treatment

First of all, after assessing the condition of the cornea of ​​the four-legged patient, the veterinarian decides whether it is possible to solve the problem with the help of conservative therapy or whether more serious surgical intervention is required.

Traditionally, treatment involves the use of medications:

1. Antibiotics. If ulcerative keratitis is caused by an infectious agent, then local antibacterial drugs are prescribed. Ointments or medicinal fluids are applied to the surface of the eye. Medicines are selected individually, depending on the infectious agent, the severity of the lesion, breed and age of the animal. Most often, the specialist recommends the use of Tetracycline, Erythromycin eye ointment, provided that the pathogen is sensitive to similar antibiotics. When infected with Pseudomonas aeruginosa, a Polymyxin M sulfate solution is instilled into the dog’s eyes, and Neomycin is administered under the conjunctiva.
2. Preparations that dilate the pupil. For these purposes, the medicine Atropine in the form of an ointment or solution is successfully used in ophthalmology. The drug is used every 8-24 hours, gradually lowering the dosage.
3. Antiviral drugs. Their use is required for the herpetic form of ulcerative keratitis in dogs. A solution of Trifluridine or Idoxuridine is instilled into the affected eye with an interval of 4-6 hours, until clinical improvements can be achieved. Then within 1-2 weeks the dosage is gradually reduced.
4. Preparations with anticollagenolytic effect. Acetylcysteine ​​is most often used to treat corrosive ulcerations. 20% of the drug is diluted in artificial tear fluid until the concentration is 5-10%. The resulting product is instilled into the eye, with an interval of 2-4 hours. In addition, it is allowed to mix this drug with antibacterial drugs, for example, Gentamicin is added to Acetylcysteine ​​and the drugs are diluted with an artificial tear.
5. Nonsteroidal anti-inflammatory drugs (NSAIDs). Drugs in this group have a pronounced anti-inflammatory and analgesic effect. Acetylsalicylic acid (Aspirin) is often used to treat animals from this group, for dogs a single dose is 10-15 mg, given at intervals of 12 hours.

If the veterinarian prescribes several drugs, then they should be used with a mandatory break, which should be at least 5 minutes.

If the pet suffers from chronic erosion of the cornea, then traditional therapeutic methods will not help, since they do not ensure the attachment of epithelial cells.

The following treatment methods are used to treat a chronic ailment:

1. Removal of loose epithelial tissue using a cotton swab. After the procedure, a damaged surface is exposed, which most often turns out to be more extensive. After that, drugs with a pronounced antimicrobial effect are applied to the cornea. For the procedure, local anesthetics in the form of eye drops are used. The event has low efficiency, and the patient requires several treatments with a certain interval. Corneal tissues heal slowly, often in their place a coarse scar tissue forms.
2. Keratomy is a method in which a number of different incisions are applied to the surface of the corneal layer, having a depression in the surface of the stroma. An insulin needle is used during the event. If the dog responds calmly to doctors and intervention, local anesthesia is used. But more often, animals need sedation, which is combined with the coating of the organ of vision with an apron of the third century, which increases the healing rate. The effectiveness of surgery on average is 70%.
3. Processing erosion area with diamond boron. This is a specific device suitable for scarification of the cornea. With its use, the ophthalmologist removes loose areas of the epithelium, creating a surface suitable for better engraftment of the renewed tissues. Among the advantages of this procedure, the possibility of carrying out it without the use of general anesthesia can be noted, only the introduction of a drug with a local anesthetic effect is sufficient. In some cases, the procedure needs to be repeated after 1-2 weeks, there are risks of the formation of rough scars during the healing of injuries.
4. Keratectomy is an operation during which the upper corneal layer is removed along with the affected thin basement membrane layer and part of the stroma. Healing of erosion occurs due to the complete restoration of the surface part, and not just the epithelial layer.

If the disease is not treated with any form, serious complications can be expected, the pet may become blind or completely lose its eyes. To avoid such serious conditions, you should be more careful about the health of the pet, especially if there is a predisposition to eye diseases. Even with minor pathologies, the dog needs to be examined by a veterinarian.