This pathology is associated with an increase in pressure inside the eye, which occurs against the background of any disease of this organ. This is a serious illness that can, in some cases, deprive pets of vision, significantly complicating their lives. This means that glaucoma in dogs and other pets requires treatment, and owners need to be more attentive to their pets.
Causes of Glaucoma in Dogs
There are many factors that, if not directly, then indirectly, provoke the occurrence of glaucoma, increasing the risks. In some cases, the pathology is associated with the breed of the animal.
At the initial stages, the disease does not manifest itself in any way, usually it is detected only with significant progression. Therefore, if the owner has the slightest suspicion of a possible change in vision in the pet, it is worthwhile to undergo a preventive diagnosis.
The following conditions and phenomena can affect the visual impairment of dogs:
- The risk group includes representatives of the following breeds: spaniel, beagle, dalmatian, husky, Samoyed husky, hounds, Labradors.
- If chronic eye ailments, including conjunctivitis, are not treated, then the development of irreversible processes leading to subsequent blindness is possible.
- Therapy of the organs of vision with steroids significantly increases the risk of glaucoma, while the disease can rapidly progress.
- Pet age - in older dogs, glaucoma is diagnosed more often than in young individuals.
- Genetic tendency - owners are advised to ask whether there was a similar disease in the family and pet, usually indicated in the pedigree. If the answer is yes, then it is advisable to bring your pet to the veterinarian regularly for a preventive examination.
- Injury to the organ of vision - this factor is considered fundamental not only for glaucoma, but also for cataracts. In this case, the animal needs emergency medical care, since irreversible processes often occur quickly.
In addition, the disease often occurs against the background of other diseases: diabetes, hypertension, atherosclerosis, etc.
Classification and types of disease
There are several types and forms of pathology. Depending on the cause of glaucoma, distinguish between primary and secondary disease. In the first case, the disease occurs in a healthy dog, and there are no provoking factors and tendency. In the second, pathology is associated with existing eye diseases, a violation of the position of the lens or uevitis.
In addition, glaucoma is divided based on the angle of the anterior chamber: closed, open or narrow. Both types of classification are used for this pathology and are found in a variety of variations:
- Hereditary form of the disease. The predisposition to pathology at the gene level is quite strong, therefore, when diagnosing primary glaucoma, it is necessary to examine and treat not only the diseased eye, but also the second, completely healthy and without signs of impairment.
- The primary type of open angle glaucoma. This is a hereditary pathology that affects primarily the beagle and the poodle. Pathology is chronic, an increase in intraocular pressure occurs slowly and gradually. Even with significant progression, the vision of the pet is maintained.
- Goniodysplasia. As a rule, Samoyed huskies, Labradors, cockers, and representatives of the hounds are affected by this primary glaucoma with a narrow angle. The disease is accompanied by severe symptoms, and with damage to one eye, the second needs to be examined. A decrease in intraocular pressure is possible, but there is a risk that the angle will close and the dog will go blind.
An ultrasound is prescribed if there is an increase in the size of the eyeball.
Symptoms of the disease
Like most diseases, glaucoma begins to manifest only as it develops. Therefore, doctors recommend, at the slightest sign, to take the pet to the clinic for examination. A progressive disease is accompanied by the following symptoms:
- excessive secretion of tear fluid;
- severe hyperemia of the mucous membrane of the eye caused by episcleral swelling;
- lethargy and apathy, the dog refuses active games and other favorite activities;
- turbidity sclera;
- an increase in the size of the visual organ, this phenomenon is also called the "bull's eye";
- soreness not only in the eye, but in the entire half of the muzzle from the inflammatory process;
- a complete refusal of food or a partial loss of appetite;
- isolation - the pet does not want to communicate with family members or with other animals;
- the development of partial disorientation;
- fear of light, the dog tries to hide in a darker place;
- the retina, optic nerve atrophy, and the dog becomes blind - this is the result of strong pressure on the blood vessels of the circulatory system.
All of the above symptoms of the disease are considered common, but their combination and intensity largely depends on the type of ailment and the degree of its progression.
In addition, the primary form of pathology may not have any symptoms at all. In this case, the disease can be detected only by measuring intraocular pressure. Also, this type of disease sometimes causes the following symptoms:
- swelling of the cornea of the eye;
- pupil dilation;
If the disease develops for a long period of time, the symptoms become more vivid, the symptoms intensify. Secondary disease has similar symptoms, but it is important to consider that they signal the development of the underlying pathology or underlying cause.
To identify eye pathology, specific methods are used with the use of special devices:
- Tonometry. With the help of a tonometer - Schiotz or applanation, the pressure inside the eye is measured in the animal. In healthy dogs, this indicator varies between 15-25 mm Hg. Art. With an increase in this value, the dog is diagnosed with glaucoma, with a decrease, it is most often left. The pressure should be the same in the right and left eye, the difference is more than 10 mm Hg. also considered as a sign of glaucoma.
- Gonioscopy This method allows you to examine the anterior chamber of the eye, determine its angle, due to which glaucoma, if any, or other diseases of the organs of vision are detected. The ophthalmic procedure is carried out using goniolins placed on the corneal surface. Because of the lens, the outgoing light is refracted and makes it possible to observe the angle and classify the pathological condition.
Veterinarians warn that it is not worth waiting for a complete cure. Unfortunately, the owners bring the pet to the veterinarian already with progressive glaucoma, when the condition of the sick animal is noticeably worsening. And in this case, a large number - up to 35%, of the nerve fibers of an organ have already died.
Therapy of the disease, begun at an early stage, allows the animal to maintain vision, but not restore it to its previous level. Often, specialists are faced with negative results from the use of folk remedies. It is strictly forbidden to do this, since usually such experiments end with the need to completely remove the eyeball in order to save the animal’s life.
Treatment includes the following aspects:
- Decreased pressure inside the eye. Since glaucoma occurs due to high intraocular pressure, the first thing that specialists care about is a decrease in performance. For emergency care, the osmotic diuretic Mannitol is prescribed, which is administered intravenously.
- Cyclocryotherapy. A method to stop the progression of glaucoma. It consists in the effect of cold on the ciliary body of the eye, which leads to a decrease in the production of ocular fluid and eliminates the likelihood of an increase in pressure. If therapy is carried out at the initial stage of the disease, a complete cessation of the pathological process is possible.
- Reception of funds that normalize the outflow of intraocular fluid and inhibit its production:
- prostaglandins (Latanoprost, Travoprost);
- m-Cholinomimetics (Pilocarpine, Aceclidine, Fosfakol, Proserin) - have a pronounced hypotensive effect;
- adrenoblockers - non-selective (Timolol) and selective (Betaxolol) - reduce the secretion of intraocular fluid;
- adrenergic agonists (Clonidine, Brimonidine);
- carbonic anhydrase inhibitors (Azopt, Diakarb, Trusopt) - are able to suppress fluid production by 50% or more.
The selection of suitable medications is carried out by a specialist, based on the results of diagnosis, analysis and the condition of the animal. In addition, the doctor must identify the root cause of the pathology.
In the conditions of a special ophthalmic veterinary clinic, they perform an surgical intervention that increases the outflow of excess moisture (drainage tubes are implanted in the body) or reduces the synthesis of moisture (partial destruction of the ciliary body using a laser or cryodestruction).
But often medication and minimally invasive therapy do not give the desired result, then the veterinarian may recommend enucleation - removal of a painful organ, or evisceration (exentration) - also removal, but with subsequent prosthetics of the eyeball.
Unfortunately, often animals with an advanced form of the disease, suffering from severe pain and damage to both eyeballs, get to the doctors. In this situation, it will not be possible to avoid the removal of the affected organs, especially since in most cases the animal has either very low vision or is completely lost.
Dogs that have been in pain for a long time, while their vision has been steadily declining, quickly adapt to new conditions. Thanks to the delicate sense of smell and excellent natural coordination, the pet is gradually returning to its former life. But, of course, he needs care and care more than his sighted brothers.
Glaucoma is a serious disease that can deprive a pet of vision. Therefore, with the existing predisposition, it is more often necessary to pay attention to the eyes of the pet and not to forget about mandatory preventive examinations.