Eye diseases in dogs, puppies: symptoms, treatment, photo. Restless dog with dilated pupils

Cataract - limited or diffuse clouding of the lens. The lens is a large transparent lens located inside the eye and provides a precisely focused image on the retina. The lens is able to change its curvature (accommodate), providing a clear image on the retina from objects that are both close and far from the eye. With a mature, completely opaque (usually milky blue) cataract, not only the mechanism of accommodation is disturbed, but the flow of light to the retina is almost completely stopped, while the eye practically stops seeing. The causes of cataracts are many. It is congenital and acquired; hereditary, complicated (as a result of any previous eye diseases or associated with general diseases: diabetes, diseases thyroid gland), traumatic. The timing of the appearance and maturation of cataracts is different, they depend on the cause of its occurrence and vary from several hours to several years. Using the biomicroscopy method, it is possible to diagnose the disease on the very early stage. Application drug treatment at this stage can slow the progression of clouding and vision loss.

Cataract treatment is only surgical, the purpose of the operation is to remove the clouded lens and restore the normal flow of light to the retina. The operation is technically complex and, of course, expensive.

But not in all cases, surgery can help. Unfortunately, with congenital cataracts (when the lens is cloudy from birth), a decrease in light stimulation of the central visual pathways during the formation of light sensitivity (the period from the opening of the eyelids to approximately 12 weeks of age) can lead to serious neurophysiological abnormalities. It has been experimentally proven that the lack of adequate light stimulation of the central nervous system causes irreversible functional and structural anomalies of the lateral geniculate nuclei and the visual part of the cortex.

This phenomenon is called amblyopia - and means the complete irreversible absence of visual functions in the affected eye.

In the presence of such a severe pathology, it is imperative to take into account the fact of its inheritance. The inheritance of cataracts is known in many different breeds and species of animals. At the same time, cataracts can be inherited in the same breed by several different ways. Although the predisposition to develop cataracts is very common among different breeds, do not make claims about heritability this disease no evidence of intergenerational transmission of the disease. However, it is necessary to follow general recommendations: do not use in breeding animals with developed cataracts of unknown origin .

June 2001

Many pet owners face such a problem: the animal grows old, and gradually its eyes become covered with an opaque veil. The same thing happens with people. As we age, so do our eyes. There are many age-related eye conditions and one of them is cataract. But the cause of cataracts is not only age. Oddly enough, cataracts can appear in an animal at any age.

Cataracts are more common in dogs than in cats, and Cocker Spaniels, Boston Terriers, Wirehaired Fox Terriers, and Poodles are particularly susceptible. Since cataracts can appear at any age, they are classified according to age (youthful or senile), shape and location, cause (hereditary, diabetic, stressful, traumatic, inflammatory, as a result of malnutrition, natural aging or injury) and the degree of obscuration.

Cataracts are fairly easy to diagnose as they are visible to the naked eye. The animal develops a "milky" film on one or both eyes, and it does not orient itself in the house as well as before.

Sometimes with age, the lenses begin to lose moisture, and a bluish haze appears. It's relative normal phenomenon known as nuclear sclerosis. It usually does not require treatment as it does not affect the animal's vision and should not be confused with cataracts.

If you notice the appearance of any haze on the pupil of the animal, contact your veterinarian to find out correct diagnosis. A cataract develops when the cells and protein in the lens of the eye begin to experience degenerative processes. As the opacity develops, it gradually blocks the light that must pass through the eye to the retina in order for the animal to see.

Surprisingly, at first, some types of cataracts do not affect the animal's vision. But when it does, the eye can go blind and special treatment may be needed. Cataracts that cause blindness, of course, change the way of life active dogs and cats, but, as with any handicap, animals adapt to this state. Dogs and cats rely on their keen senses of perception—smell and hearing, perhaps even more than sight. In the process of adaptation to blindness, these senses, of course, come to the fore and are improved to the level of a high-tech radar device that ensures the safe navigation of the animal. Pets, such as cats and dogs, usually quickly adjust to seeing with one eye or not seeing at all. Of course, they need extra attention from the owner so that he does not rearrange the furniture in the apartment too often and does not let the dog go outside without a leash. Street animals get used to blindness a little more difficult, but they also cope with it.

If the cataract affects both eyes, surgery may be considered as a treatment option. Need surgical treatment in each case, only the veterinarian determines. To eliminate blindness caused by cataracts, the veterinarian removes the lens of the eye. When the lens is removed, the cataract does not re-develop. There are several stages in the development of cataracts. The task of the veterinarian is to determine when the cataract is mature, as this is the optimal stage for its removal. However, if the cataract develops as side effect other pathologies of vision, its removal will not restore the vision of the animal. I recommend cataract removal only in cases where both eyes are affected. If the cataract is in only one eye, surgery is not necessary. Don't expose your dog or cat to injury (and the owner to expenses) surgical intervention if the animal has one healthy eye.

After cataract surgery, the restored vision of the animal will be blurry, because in the absence of a lens, the eye cannot focus the “picture”, but the animals do not need to read the morning newspapers. They are also happy that they can just play with their owner and look at favorite face, even if it's a little blurry around the edges.

Go to the doctor and everything will clear up right away.

And as always: than more so better.

The disease does not progress very quickly and the dog adapts to the progressive loss of vision (there is a loss of vision and it only seems that she sees everything).

Wouldn't like to tell horror stories, but if you run hard, you can get to the removal of the eye / eyes.

Expensive operation or not, everyone himself must try on his wealth and his love for his dog. I did it quite a long time ago (I think about five years ago) and it cost about 20,000 rubles. Unfortunately, I don't remember where.

There are cataracts gray, senile, black and green. Gray cataract is a disease of the lens and

occurs quite frequently. AT healthy eye the lens is vitreous and transparent. The pupil, behind which the lens is located, is black in a normal eye.

With a black cataract in the lens appears varying degrees a deformity that more or less limits the ability to see. At the same time, the pupil becomes white or gray. Gray cataract occurs different reasons: it can be congenital (fetal development disorders), a consequence inflammatory processes or eye damage. Less commonly, gray cataract is caused internal diseases such as metabolic disorders, diabetes or infectious diseases. An incorrect prejudice has taken root that overfeeding a dog with sugar leads to blindness. This is completely false.

The development of gray cataract cannot be delayed pharmacological agents, nor cure. In young dogs, it is sometimes eliminated operational way. However, the operation returns the ability to only distinguish between light and dark. An eye devoid of a lens becomes farsighted - the dog does not recognize nearby objects. Unfortunately, farsightedness cannot be corrected with optical lenses in dogs, as is done in humans.

More common senile cataract that develops in dogs over the age of 10 years. Already a few years earlier, it can be seen on the lenses in both eyes light a grayish sheen, called the "reflex of old age." Later, a gray-white or gray-blue clouding of the lens develops gradually, evenly increasing. Such a dog sees only light and dark.

Despite these changes, the animal is able to navigate relatively well with the help of scent, so that the owner temporarily does not notice the developing disease.

In some forms of cataract, the lens is wrinkled, and potash salts or other substances are deposited in it, so that the pupil has a mother-of-pearl appearance. In this case, the lens does not let light into the eye at all, and the dog becomes completely blind.

Black cataract. This term defines a series different states defeat optic nerve, retina and less often also lesion visual center in the brain. This disease occurs as a result of inflammation of the eyeball or brain, in the case of infectious diseases, after poisoning, and can also be caused by other causes.

A characteristic feature of a black cataract is dilated and motionless pupils. In a healthy eye, the pupil expands in the dark, and immediately narrows when it comes out into the light.

This can be easily verified by suddenly illuminating the eyes in the dark with a lantern. With a black cataract, such a reaction does not occur, the pupils do not narrow. This indicates that the light-sensitive elements of the eye have ceased to respond to optical stimuli, and the affected eye is blind. Finally, the so-called stool test can be a tentative indication of bilateral absolute blindness. It consists in the fact that the dog is repeatedly led along the same line on a long leash, at a certain point along the way it is placed across a stool. On the basis of the behavior of the dog, as he acts when he encounters an obstacle, you can evaluate his ability to see. Black cataract is usually incurable.

Green cataract or glaucoma, characterized by

an increase in pressure in the eyeball as a result of the fluid it contains.

Over time, the pressure causes damage to the optic nerve and thus leads to blindness. Glaucoma can develop due to another eye disease, but it can also appear on its own without a distinct apparent reason.

With severely developed glaucoma, the eyeballs are tense and enlarged. Sometimes there is photophobia and lacrimation. As with black cataracts, glaucoma is characterized by dilated pupils. You can often notice a green reflex of the pupils - hence the name - glaucoma or green cataract.

The treatment is to reduce the pressure inside the eyeball. For this purpose, pupil constricting drugs are instilled into the eyes, along with others, and cold compresses are also used. In some cases, surgical treatment is indicated.

Why does a thorn appear in the eye of a dog and how to treat it?

can be viral and traumatic, and treated by a veterinarian

WebRazum Student (185) 4 years ago

this is most likely not a thorn, but a "third eyelid" - it is treated with drops prescribed by a veterinarian

uncleVova the Thinker (5911) 4 years ago

Clouding of the lens (cataract).

Cataract is an eye disease, the main symptom of which is clouding of the main substance or lens capsule (reduction of their transparency). accompanied by a decrease in visual acuity. The causes of cataracts are very different: toxic and radiation effects, trauma, hormonal disorders, age-related changes, etc.

It is possible that the dog for a long time is in a state of emotional arousal, although there is no apparent reason for this. If this is the case, you should contact a veterinarian - an ophthalmologist, who will determine why the dog's pupils are dilated. Also, you may need to consult a neurologist or psychoneurologist to understand and consider all aspects of the problem.

It happens that the dog's pupils are dilated and do not respond to light changes, because the dog has lost his sight.

It should be noted that this occurs at the same time emergency situations: as a result of traumatic brain injury, serious neurological disease that gave complications to the eyes of a dog, an infectious or viral disease.

In other cases, blindness may occur for some time in older dogs, as well as serious illness, which the dog suffered, was left without attention and the animal was not treated.

Permanently dilated pupils may be the body's response to exposure medicines or chemicals that depress the nervous system of the animal and the visual apparatus.

In this case, you must contact the veterinarian, otherwise, if you had a young and healthy dog, you can get a sick animal that will remain disabled for life.

Pupil dilation in a puppy should also cause concern. Despite the high emotionality of babies, mental arousal should conduct, and the pupils should return to normal condition.

If it is impossible to understand what to do when the unreasonable dilation of the pupils in a puppy is observed long time contact a specialist immediately.

Anisocoria in dogs and cats

Anisocoria means an inequality in the size of the pupils, is not actually a disease, but accompanies another pathology. There are approximately 30 reasons for this phenomenon: corneal injuries, age-related changes in the iris, adhesions, changes intraocular pressure, transmission failure nerve impulse, tumors and pathologies of the retina. Disorders of the activity of the brain and spinal cord can change pupil size. Anisocoria can appear at any age.

Pupil size regulates the amount of light entering the eye. If one pupil is more dilated than the other normal eye, bright light can impair vision to the extent that the light is intense. The animal usually compensates for the excess light by partially covering the eye with the eyelid. If the affected eye has a constricted pupil, then vision in bright light is normal, but in subdued lighting, vision deteriorates. Despite the disease in animals persists good vision and signs of discomfort are mild or non-existent. In some cases normal function the pupil returns over time, even in the absence of treatment. Also in other cases, anisocoria persists for a long time (sometimes a lifetime), depending on the cause of the condition.

Treatment depends on the clinical signs present. The cause can be clarified during examination or other diagnostic methods. In some cases, the cause may remain unexplained due to limited or inaccessible diagnostic methods, or the economic opportunity of the owner of the animal. The tactics of treatment are determined by the history of the disease, concomitant Clinical signs, age and general state animal health.

Restless dog with dilated pupils

The dog sits motionless, the pupils are dilated, she is extremely nervous, raises her paws - now the left, then the right.

Answer

Hello! It is difficult to understand the reasons for strange behavior dogs from short message. The described symptoms are best studied in conjunction with other indicators. What is the pet's temperature? Are there discharges from the eyes, ears? How long has the dog been sitting still? What is the meaning of the expression - extremely nervous? We give an answer only about the described signs.

Why do dogs have dilated pupils?

1. Often in pets, the pupils dilate from anxiety, fear, or excessive excitement. Usually the expansion takes place within a short time.
2. Pupil dilation when the pet does not respond to external stimuli(for example, increasing or decreasing the brightness of the light), indicates a possible vision problem. You will need to take your pet to an ophthalmologist for a diagnosis.
3. There is an instant loss of vision. In the latter case, the pupils are dilated, the dog is depressed. The body's reaction - instantaneous blindness - is possible in case of a skull injury, or as a complication after a severe neurological, viral or infectious disease.
4. If the dog is old, the likelihood of vision loss increases. Perhaps the blindness has been progressing for several weeks and has only now become noticeable.
5. Pupils dilate as a result of treatment strong drugs, or the pet was affected by an unknown Chemical substance, there was a poisoning of the body.

Remember, any oddity in behavior - aggressiveness or, conversely, depression - deserve close attention. It is better to urgently consult a doctor to find out the reasons for the inadequacy of the animal.

Nervousness in dogs is considered a symptom complex disease or bad mood. If we consider nervousness and involuntary raising of the limbs together, a picture of possible diseases arises.

Possible Causes of a Dog's Nervousness

As a serious unfavorable prognosis, nervous form distemper. Absence of other symptoms of the specified disease: discharge from the eyes, ears, increased salivation and temperature, they will only say that the virus has affected the nervous system of the animal. The pet becomes shy, shies away from the owner or familiar objects. You need to call a doctor and try to save your pet from unnecessary contact with people.

Involuntary lifting of the paws indicates a strong pain syndrome. In conjunction with dilated pupils, it is logical to assume muscle contractions, convulsions. Seizures are not a disease, but an indicator of a disease. This behavior of the animal indicates a pathology in the body that requires urgent intervention. If the dog does not return to normal for a long time, go to the vet. Self-diagnosis is undesirable. Even measuring the temperature will result in a sudden increase in seizures.

A neurological disease can also be the cause of the described odd behavior. The animal developed pain in the joint of one or both paws. Ligament sprain causes compression of the limbs. It is difficult to talk about neuralgia without tests. If the dog raises its paw and the limb hangs, they talk about damage to the radial nerve. Known diagnosis of paralysis ulnar nerve- the dog's paw falls under the body when trying to put it straight. A neurologist will help if you apply in time to avoid unfavorable prognosis.

Tightening of the paws, possibly a sign pain syndrome in the paws. Did the surface of the pads get damaged during the last walk or at home? An option would be a splinter in one or both limbs at once. It is necessary to examine the pet for the presence of a cut or puncture of the pads, damage to the claws. With visible integrity, it is better to agree on an x-ray in order to exclude the possibility of the consequences of spinal disc deformation.

How to understand pet behavior

Dogs do not speak human language, they will not say in words about the location and nature of the pain. Watch your pet. Take every change in behavior as a sign to action. See a doctor, describe the symptoms, take a video. Help four-legged friend- He asks you for help.

"Eye diseases in dogs. Consulted by Ph.D. Komarov S.V."

Graduated from MGAVMiB in 2001, defended his dissertation on eyelid surgery in dogs for the degree of candidate of veterinary sciences in the specialty of surgery,

the main specialization is ophthalmology of small animals. Therapy, plastic procedures, microsurgery of the organ of vision and auxiliary structures.

I work in Moscow veterinary academy(MGAVMiB) at the Department of Biology and Pathology of Small Domestic, Laboratory and Exotic Animals (http://www.bmdg.ru),

as well as in the center for the treatment of eye diseases of animals (http://www.okovet.ru).

If someone needs a face-to-face consultation, please call, come, I will be happy to help. t11.

What to do, if:

1. Injury in which the eye crawled out (bite, blow) -

cover the eye with ointment (levomekol can be used), on temporal region apply a cold object (ice) to reduce swelling / hematoma namin, inject an anesthetic (if possible) and run to the doctor (primary surgical treatment with determining the degree of injury). The result directly depends on the severity of the injury, the time of treatment and the qualifications of the doctor.

It is necessary to set the eye behind the eyelids, fix it, antibiotics + anti-inflammatory + antioxidants. Approximately in a day to correct strabismus, which, as a rule, accompanies traumatic prolapse (loss) of the eyeball

There are 4 degrees of traumatic eye prolapse (specially I write in simple words). With the first 2 it is possible to save the eye and vision, with the 3rd - a maximum of the eyes, with 4 even the eye can not be saved.

Actions: Cold (15-20 min.), see a doctor. If blood is seen inside the eye - a poor prognostic sign - it is probably a rupture. Required: examination, ophthalmoscopy, tonometry, ultrasound (research methods). The result is determined further tactics treatment.

At mild degree- drops + ointments + injections. In severe cases - surgery + drops + ointments + injections.

Indeed, I only know Kopenkin (junior) and Chernousov. Heard about Shilkin. I also heard, or rather read Peche's website. I do not remember.

Veterinary Forum

A friend has a dog. The dog sometimes has pupils of different sizes, the dog does not seem to be bothered by this. They showed the vet how I don't know, but they diagnosed me with an increased intracranial pressure.

The dog doesn't care. By at least she doesn't talk about it.

A friend has a dog. The dog sometimes has pupils of different sizes, the dog does not seem to be bothered by this. They showed the veterinarian how I don't know, but they diagnosed me with increased intracranial pressure. They prescribed furosemide, veroshpiron and persen, like everything. They treated, for a while everything was fine, but now again. I somehow can’t believe about the pressure, what else can be different pupils?

2. Inflammatory processes.

Can I attach a photo here? It's probably better to see it once.

Thanks for the answers, DOCTOR-VeT! Are these problems treated? Or maybe there will be some aggravations in the future? Because if it remains so, then nothing else, this state of affairs does not bother him in any way. That wouldn't get any worse.

What kind of infection could it be? And when will it be possible to take tests for it? Now we are treating pneumonia. Almost healed.

What would you recommend getting tested? On occasion, we could take the blood. Here, the closest thing to Zaitsev, it seems that you can check somewhere. Or in Lomonosov ..

I have a husky for 3 months. Tonight she woke up, and she had one pupil very narrow, and the second behaved adequately .. the pupil returned to normal in minutes. while the eye is red but does not bother her.

What could have caused this? It didn’t happen before .. I don’t know what to do. =(

Could it be a puppy dog? Or an accident.

Pupils of different sizes: anisocoria in cats and dogs

The primary task of the doctor is to determine which icon is abnormal: narrowed or expanded. To do this, the pupils are observed with the light turned off (the pathologically narrowed pupil will not expand, but will remain narrow). Next check pupillary reflex(A pathologically dilated pupil will not respond to light).

Thus, they determine what they had to deal with: unilateral miosis or mydriasis.

Miosis - pupillary constriction, can be observed in conditions such as uveitis, superficial corneal defect, Horner's syndrome.

Uveitis - inflammation choroid eye, additionally accompanied by symptoms such as turbidity of the intraocular fluid, precipitates on the corneal endothelium, decreased intraocular pressure, and conjunctival hyperemia (Fig. 1). These symptoms help differentiate uveitis from other diseases. For the treatment of uveitis, local and systemic anti-inflammatory therapy is used.

Miosis with superficial damage to the cornea occurs reflexively due to irritation trigeminal nerve. Surface damage It is also easy to differentiate using a fluorescein test and a slit lamp (Fig. 2), some foreign bodies can be seen even with a flashlight pen. To treat such patients, it will be necessary to find and eliminate the provoking factor ( foreign body, pathology of eyelash growth) and continue to use a local antibiotic.

Miosis in Horner's syndrome is caused by a violation sympathetic innervation iris and is combined with ptosis of the eyelids, protrusion of the third eyelid and enophthalmos (Fig. 3). visual function does not suffer from this syndrome.

Anatomy (sympathetic innervation)

Damage to any part of this pathway can cause Horner's syndrome, depending on the location of the damage, a syndrome of the first order (hypothalamus - spinal cord), second order or preganglionic (spinal cord - cervical ganglion) and third order or postganglionic (cervical ganglion - eye) are distinguished.

Instillation of 0.1 ml of a 0.001% solution of epinephrine causes dilation of the pupil of the affected eye after 20 minutes with postganglionic damage and after 30–40 minutes with preganglionic damage.

When using a 10% solution of phenylephrine, mydriasis that occurred after 20 minutes indicates postganglionic syndrome (3rd order), after 20–60 minutes - preganglionic (2nd order) and after 60–90 minutes - preganglionic ( 1st order), during the same time mydriasis occurs on a healthy eye. A 2.5% solution of irifrin is also successfully used for diagnosis.

During pharmacological tests, in addition to the onset of mydriasis, protrusion of the 3rd eyelid and ptosis disappear in the affected eye.

Horner's syndrome

Treatment for Horner's syndrome

Mydriasis in glaucoma occurs due to impaired innervation, vascularization, and subsequently thinning of the iris and is accompanied by typical features glaucoma: increased intraocular pressure, corneal edema, Gaab stripes, decreased vision up to total loss(Fig. 5). These signs and tonometry are used to diagnose glaucoma. Treatment of glaucoma may consist of local and systemic antihypertensive drugs, surgical methods.

In the case of retinal detachment, mydriasis may be observed, and the pupillary reflex may be reduced or absent (Fig. 6). In this case, with ophthalmoscopy, you can see a picture characteristic of detachment. If for some reason ophthalmoscopy is not possible (clouding of the cornea or lens), then in this case, using ultrasound, it is possible to establish the diagnosis of "retinal detachment" by characteristic picture. If the cause of detachment is arterial hypertension, then the system antihypertensive therapy may in some cases cause the retina to return to its normal position and help restore vision.

With optic neuritis, mydriasis, absence of the pupillary and dazzle reflex, and lack of vision are observed (Fig. 7). With ophthalmoscopy, you can see signs of optic neuritis: the disc is edematous, pink, protruding into vitreous body, but if the nerve is inflamed retrobulbar, ophthalmoscopy may not reveal pathology. In this case, they resort to examination using the Iris-vet device: with optic neuritis, there will be no pupil reaction to either blue or red light.

MRI diagnostics can provide more information and identify foci of inflammation, volumetric formations. For the treatment of the optic nerve with neuritis, systemic steroid hormones are most often used.

With atrophy of the iris, mydriasis and reduced or even absent pupillary response to light due to age-related changes(atrophy) of the iris sphincter muscle (Fig. 8). With atrophy of the iris, vision does not deteriorate, and such patients do not need to be treated.

Mydriasis with a lesion parasympathetic innervation irises

In the midbrain there are Edinger-Westphal nuclei, parasympathetic axons emerge from them and, as part of oculomotor nerve(CN III) go into orbit. There is a ciliary ganglion in the orbit, where a synapse occurs, postganglionic fibers as part of short ciliary nerves enter into eyeball and innervate the sphincter muscle of the iris.

In dogs, short ciliary nerves are distributed evenly over the iris (5–8 pieces), therefore, if parasympathetic innervation is disturbed in dogs, the pupil is dilated, in cats, there are 2 ciliary nerves - malar and nasal, with an isolated lesion, a D-shaped or vice versa is observed -D-shaped pupil. In violation of parasympathetic innervation, vision does not change (Fig. 9).

Localization of violation of parasympathetic innervation: pharmacological tests

One drop of a 0.5% solution of physostigmine causes rapid pupillary constriction in preganglionic damage (physostigmine can cause miosis if the postganglionic neuron is normal). In a healthy eye, miosis will occur in 40–60 minutes.

Two drops of a 2% solution of pilocarpine cause rapid and complete pupillary constriction in postganglionic injury. If the narrowing does not occur with the use of drugs, then other causes of mydriasis are considered.

Causes of impaired parasympathetic innervation

Treatment for violation of parasympathetic innervation

Anisocoria can occur in many diseases, some of which are ophthalmic, some are neurological. A thorough examination is required to accurately determine the cause of anisocoria and prescribe treatment.

• Maggs D. J., Miller P. E., Ofri R. Slatter’s fundamentals of veterinary ophthalmology 5ed. Elsevier. St. Louis. 2013, 506 p.
• Gelatt K. N. Veterinary Ophthalmology 5ed. Wiley Blackwell. Ames. 2013, 2170 p.
• Jaggy A., Couteur R. Small animal neurology. Schluetersche. 2010, 528 p.
• Lorenz M. D., Coates J., Kent M. Handbook of veterinary neurology 5 ed. Elsevier. St. Louis. 2010, 560 p.
• Grozdanic S. D., Kecova H., Lazic T. Rapid diagnosis of retina and optic nerve abnormalities in canine patients with and without cataracts using chromatic pupil light reflex testing. Veterinary Ophthalmology. 2012: 1–12

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DIFFERENT PUPILS IN THE DOG. Anisocoria

What is anisocoria?

Anisocoria is a common problem in dogs, it is pupils of uneven size, when one pupil is dilated and the other is underdeveloped. The causes of anisocoria in dogs can be different: deviations in nervous system, infection, inflammation, cancer, or injury to the eye.

The reasons

Causes of abnormalities in the nervous system:

Violation of the optic nerve, especially the nerve of the eye.

Violation ophthalmic nerve, cranial nerves that are responsible for muscle movement of the eye

Cerebellar dysfunction

Violation of the work of vision, optic fiber.

Causes of deviations visual system:

Anterior uveitis (inflammation of part of the eye)

Glaucoma (increased eye pressure)

Drugs that change pupil function

Constricted pupil syndrome

Anisocoria may be associated with large quantity disease processes, can also indicate severe or fatal diseases.

Symptoms

Changing pupil size

Changing the shape of the eye

Change in color or cloudiness of the eye

When your dog has different pupils and you, not knowing what to do, are looking for advice on this topic on the Internet in the forums, we recommend that you do not self-medicate and experiment on your beloved pet. The fact is that there are many reasons for anisocoria in an animal, and the consequences of your experiment may disappoint you and your family.

Diagnosis of anisocoria in dogs

Complete Analysis blood

Biochemical analysis blood

x-ray chest for suspected injury

Measurement of intraocular pressure

Ultrasound of the eye and eye tissue

Analysis cerebrospinal fluid

Checking the optic nerve and brain function

Tomography or magnetic resonance imaging (MRI)

Treatment

Anisocria is difficult to treat. Contact your veterinarian to find out the cause of this disease. Antibiotics and/or anti-inflammatory drugs may be used to treat the disease.

Follow all instructions from your veterinarian. Remember, do not leave your pet to avoid injury.

How to call a veterinarian at home?

What questions will need to be answered?

In order to call a veterinarian, you need:

1. Call the operator at the numbers indicated in the Contacts section;
2. Tell what happened to the animal;
3. Report the address (street, house, front door, floor) where the veterinarian will arrive;
4. Specify the date and time of the doctor's arrival

Call the veterinarian at home and he will definitely help you.

Localization of violation of sympathetic innervation: pharmacological tests

Damage to the sympathetic tract results in denervation hypersensitivity. smooth muscle to neurotransmitters (0.001% solution of epinephrine (adrenaline), 10% solution of phenylephrine (mezaton) - a synthetic analogue of epinephrine)). Denervation hypersensitivity is more pronounced with damage to postganglionic axons and cell bodies than with damage to preganglionic axons; this phenomenon is used to localize the lesion.
Instillation of 0.1 ml of a 0.001% solution of epinephrine causes dilation of the pupil of the affected eye after 20 minutes with postganglionic damage and after 30–40 minutes with preganglionic damage.
When using a 10% solution of phenylephrine, mydriasis that occurred after 20 minutes indicates postganglionic syndrome (3rd order), after 20–60 minutes - preganglionic (2nd order) and after 60–90 minutes - preganglionic ( 1st order), during the same time mydriasis occurs on a healthy eye. A 2.5% solution of irifrin is also successfully used for diagnosis.
During pharmacological tests, in addition to the onset of mydriasis, protrusion of the 3rd eyelid and ptosis disappear in the affected eye.

Horner's syndrome

Treatment for Horner's syndrome

midriaz- dilated pupil, can be observed in pathologies such as glaucoma, retinal detachment, optic neuritis, iris atrophy, as well as in violation of the parasympathetic innervation of the iris.
Mydriasis in glaucoma occurs due to impaired innervation, vascularization, and subsequently thinning of the iris and is accompanied by typical signs of glaucoma: increased intraocular pressure, corneal edema, Gaab's stripes, reduced vision up to complete loss (Fig. 5). These signs and tonometry are used to diagnose glaucoma. Treatment of glaucoma may consist of local and systemic antihypertensive drugs, surgical methods.
In the case of retinal detachment, mydriasis may be observed, and the pupillary reflex may be reduced or absent (Fig. 6). In this case, with ophthalmoscopy, you can see a picture characteristic of detachment. If for some reason ophthalmoscopy is not possible (clouding of the cornea or lens), then in this case, using ultrasound, it is possible to establish the diagnosis of "retinal detachment" according to a characteristic picture. If the cause of the detachment is arterial hypertension, then systemic antihypertensive therapy can in some cases lead to the return of the retina to its normal position and help restore vision.

With optic neuritis, mydriasis, absence of the pupillary and dazzle reflex, and lack of vision are observed (Fig. 7). With ophthalmoscopy, signs of optic neuritis can be seen: the disc is edematous, pink, protruding into the vitreous body, but if the nerve is inflamed retrobulbar, ophthalmoscopy may not reveal pathology. In this case, they resort to examination using the Iris-vet device: with optic neuritis, there will be no pupil reaction to either blue or red light.
MRI diagnostics can provide more information and identify foci of inflammation, volumetric formations. For the treatment of the optic nerve with neuritis, systemic steroid hormones are most often used.
With atrophy of the iris, mydriasis and a reduced or even absent pupillary response to light can be observed due to age-related changes (atrophy) of the iris sphincter muscle (Fig. 8). With atrophy of the iris, vision does not deteriorate, and such patients do not need to be treated.

Mydriasis with damage to the parasympathetic innervation of the iris

Causes of impaired parasympathetic innervation

Treatment for violation of parasympathetic innervation

Literature:

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5. Grozdanic S. D., Kecova H., Lazic T. Rapid diagnosis of retina and optic nerve abnormalities in canine patients with and without cataracts using chromatic pupil light reflex testing. Veterinary Ophthalmology. 2012: 1–12

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What is anisocoria?

Anisocoria is a common problem in dogs, it is pupils of uneven size, when one pupil is dilated and the other is underdeveloped. The causes of anisocoria in dogs can vary from nervous system abnormalities, infections, inflammation, cancer, or eye injury.

The reasons

Causes of abnormalities in the nervous system:

Head injury
Violation of the optic nerve, especially the nerve of the eye.
Violation of the ophthalmic nerve, the cranial nerves that are responsible for the muscles that move the eye
Cerebellar dysfunction
Violation of the work of vision, optic fiber.

Causes of deviations of the visual system:
Anterior uveitis (inflammation of part of the eye)
Glaucoma (increased eye pressure)
Muscle anomalies
eye cancer
Drugs that change pupil function
Constricted pupil syndrome
Anisocoria can be associated with a large number of disease processes, and can also indicate severe or fatal diseases.

Symptoms

Changing pupil size
Pupil displacement
Visual impairment
Changing the shape of the eye
Change in color or cloudiness of the eye
Inflammation
Pain in the eye

When your dog has different pupils and you, not knowing what to do, are looking for advice on this topic on the Internet in the forums, we recommend that you do not self-medicate and experiment on your beloved pet. The fact is that there are many reasons for anisocoria in an animal, and the consequences of your experiment may disappoint you and your family.

Diagnosis of anisocoria in dogs

Medical checkup
Complete blood count
Blood chemistry
Analysis of urine
Chest x-ray for suspected trauma
Measurement of intraocular pressure
Ultrasound of the eye and eye tissue
Analysis of cerebrospinal fluid
Electroretinography
Checking the optic nerve and brain function
Tomography or magnetic resonance imaging (MRI)

Treatment

Anisocria is difficult to treat. Contact your veterinarian to find out the cause of this disease. Antibiotics and/or anti-inflammatory drugs may be used to treat the disease.

Care and maintenance

Follow all instructions from your veterinarian. Remember, do not leave your pet to avoid injury.