Cloudy eyes in a dog often appear as a hazy film or discoloration covering the eyes. Your dog's vision may or may not be affected by the cloudiness. Some cloudy eye conditions may be painful while others are not. It will take a thorough eye exam for your veterinarian to determine the cause of the cloudiness.
What Are Cloudy Eyes?
Cloudy eyes in dogs can be a symptom of a progressive eye disease or part of the natural aging process. The cloudiness typically occurs on the cornea of the eye. You cannot miss the cloudiness because it is typically located on the cornea, which is the clear dome in the front of each of your dog's eyes.
Symptoms of Cloudy Eyes in Dogs
Symptoms of cloudy eyes vary due to the cause of the condition. Here's a list of symptoms associated with various causes, in addition to the clinical visual cue of cloudiness, to alert you that your dog may have a condition. Your dog will not experience all symptoms. But as soon as you notice changes in your dog's eyes, call your vet for a visit.
Cloudiness in Eyes
Cloudiness in the eyes can be noted in tones of gray, blue, red (rare), or white with various degrees of opaqueness. The colors may point to various causes of the cloudy condition, including the following:
- Gray or bluish: Glaucoma, lenticular sclerosis, corneal endothelial degeneration, or uveitis (inflammation inside the eye)
- Reddish: Corneal ulcer (but could also be gray/blue)
- Silvery white/gray: Corneal dystrophy
- Milky white: Cataracts
If you see your dog squinting while pawing at or rubbing one eye and it looks a bit cloudy, your dog may have a corneal scratch or ulcer. Underlying uveitis can also cause squinting and rubbing.
Red, Irritated Whites of Eyes
In addition to a bluish cloudiness in the eye, if your dog's eye whites appear to be red or inflamed, it could be a symptom of glaucoma.
Swelling or Bulge in Eye
If your dog's eyes are cloudy with a bluish tint and there seems to be a swelling or bulge inside the eye, it could also be a symptom of glaucoma.
Trouble Finding Items, Food, Bedding
If your dog is having trouble finding items, food and water, and its favorite bed or piece of furniture, check the eyes for cloudiness which could be impeding vision and plan to have the eyes checked by your veterinarian as soon as possible if vision loss is sudden.
If you notice yellowish or green discharge from your dog's eyes, in addition to cloudiness, it could have a corneal ulcer, or an infection caused by the corneal ulcer. Typically this will happen in one eye, not both. Uveitis can cause similar signs and can occur in one or both eyes.
Causes of Cloudy Eyes
There are a number of ophthalmic conditions that can make a dog's eyes appear cloudy and some of these conditions are more serious than others. Many people first assume the cloudiness is caused by cataracts. Although this is sometimes the case, cloudy eyes may occur due to other eye problems. Here are the types of conditions that cause cloudy eyes.
Also known as nuclear sclerosis, lenticular sclerosis is a normal eye condition that affects aging dogs and causes the lens of the eye to become hazy in appearance. The condition develops due to a buildup of old fibrous tissue in the lens of the eye located behind the iris. Lenticular sclerosis is common in middle-aged and senior dogs. Fortunately, the condition does not cause pain or blindness.
A cataract is an opacity on the lens of the eye. Unlike lenticular sclerosis, where the fibrous tissue builds up, a cataract causes a cloudy spot on the lens that grows over time. As the cataract grows, it blocks out light and reduces vision. When mature, cataracts can cause complete blindness, lens luxation, and painful inflammation of the eye.
Glaucoma occurs when there is increased pressure inside a dog's eye. When intraocular pressure remains high for too long, the optic nerve can become permanently damaged. This condition is very painful and can lead to blindness.
A corneal ulcer is an injury to the surface of the eye (the cornea). Corneal ulcers typically occur when the cornea becomes scraped or scratched due to friction or trauma. The injured area becomes painful and the dog may make the ulcer worse by rubbing the eye. Many other eye conditions can lead to corneal ulcers. Left untreated, corneal ulcers can cause major damage to the eye.
Corneal Endothelial Degeneration
Corneal endothelial degeneration is an age-related condition in dogs that causes opacity of the cornea. This condition occurs when the endothelial cells within the cornea no longer maintain a proper balance of fluids in the tissue of the cornea. This results in cloudiness that can lead to blindness. Corneal endothelial degeneration can cause painful secondary eye complications.
Corneal dystrophy also causes opacity to the cornea of the eye. This condition occurs due to calcium or cholesterol deposits that build up on the cornea. Some dogs are genetically predisposed to corneal dystrophy. Corneal dystrophy may cause painful corneal ulcers and lead to blindness.
The uvea is the section of the eye behind the cornea. Uveitis is inflammation of the uvea and can occur secondary to trauma, infection, or systemic disease. Inflammation can result in the accumulation of inflammatory cells and proteins that make the eye appear cloudy.
Diagnosing Cloudy Eyes in Dogs
Veterinarians give eye exams with a variety of tools to determine the cause of ocular cloudiness, including:
- Non-invasive high-resolution imaging techniques
- An ophthalmoscope
- Drops for pupil dilation
- Special stains, such as fluorescein
- A tonometer (typically used for glaucoma testing)
- Other ophthalmic lights and filters
If your dog is diagnosed with lenticular sclerosis, your veterinarian will keep monitoring your pet for cataract development. If cataracts form and are not treated, glaucoma may develop.
Treatment for cloudy eyes has a better chance of success if the eye disease is detected early. The proper treatment for cloudy eyes in dogs depends on the cause of the cloudiness:
- There is no treatment available for lenticular sclerosis, nor is treatment necessary.
- Cataracts can only be treated with surgery.
- Glaucoma is treated with topical eye medications to lower intraocular pressure.
- Corneal ulcers are treated with topical medications, but severe ulcers may require surgical treatment.
- Treatment options for corneal endothelial degeneration are limited. Medications may be used as palliative treatment. Some specialized surgical options may be available through a veterinary ophthalmologist.
- Corneal dystrophy may be treated with a special diet to regulate cholesterol and calcium levels. Topical medications may also be used to manage this condition as well as secondary problems. Surgery may be necessary in some cases.
- Treatment for uveitis depends on the underlying cause but typically involves both topical and systemic medications.
Prognosis for Dogs With Cloudy Eyes
Prognosis is often good for dogs with cloudy eyes, however, it will depend on the cause of the condition. Even if your dog's cloudy eyes result in blindness, your pet can have a long and quality life.
How to Prevent Cloudy Eyes
Cloudy eyes cannot always be prevented, but you can take precautions to protect your dog's eyes as best as possible. The best way to prevent most eye issues and other health problems in your dog is to visit the vet once or twice a year for a routine veterinary exam. This can allow the vet to detect and treat problems early, especially as your dog gets older.
Though you cannot prevent eye cloudiness that occurs with aging, as is the case with lenticular sclerosis, you can be aware of some other preventative measures:
- Cataracts: Though cataracts may be hereditary and not preventable, it helps to know that diabetes mellitus may lead to cataract development. Help prevent it by properly managing your dog's diabetes.
- Glaucoma: You and your vet can manage the eye diseases that cause glaucoma.
- Corneal ulcers: This may be most preventable if you protect your dog from traumatic injuries. In addition, try your best to keep your dog from rubbing the eyes due to other eye problems by using an e-collar, or Elizabethan collar, as a temporary aid.
- Corneal endothelial degeneration: This condition is often age-related, but may also occur secondary to other eye issues. You may be able to prevent it by identifying and treating other eye problems in your dog.
- Corneal dystrophy: You may be able to prevent this with your vet's help by keeping calcium and cholesterol levels under control. Your vet can run routine lab tests to periodically check these levels. Routine lab work is always a good way to monitor your dog's overall health.
- Uveitis: Uveitis may not always be preventable, but some cases occur secondary to infectious agents like viruses or tick-borne disease. Keeping your dog current on vaccines and preventatives can help prevent uveitis from infectious disease.
Glaucoma - Eye Diseases and Disorders. Merck Veterinary Manual.
Disorders of the Lens in Dogs - Dog Owners. Merck Veterinary Manual.