Updated date:

Nuclear Sclerosis: What Causes Eye Haziness in Senior Dogs?

Adrienne is a certified dog trainer and former veterinarian assistant who partners with some of the best veterinarians worldwide.

What causes eye haziness in older dogs?

What causes eye haziness in older dogs?

What Is Nuclear Sclerosis?

If your senior dog has begun exhibiting a bluish, hazy tint in its eyes, this may be a common sign of aging. This condition is called nuclear sclerosis, and while it is pretty common in geriatric dogs, it is always recommended to have a veterinarian or ophthalmologist assess the eyes to rule out other possible and more serious eye disorders.

Nuclear sclerosis is also known as lenticular sclerosis. It typically affects the area covering the dog's pupil and tends to affects both eyes. It does not, however, interfere with the dog's vision, and therefore, the dog will likely not bump into objects or get startled when you approach him and pet him as dogs that have vision problems.


Nuclear sclerosis generally affects dogs over 7 years old; however, the symptoms may become visible until only some time later. The cause of the cloudy appearance is due to the fact that as the pet ages, its lens become denser and harder; they, therefore, begin exhibiting symptoms of deterioration that causes the visible haziness.

As the deterioration progresses, the dog's pupils will lose their typical black color and may assume more significant changes; the pupils then appear to turn bluish or grey (due to light scattering), and often, the dog is believed to have cataracts.


Diagnosis is usually accomplished by dilating the dog's pupil with some special eye drops. Once the pupil is dilated, the vet will be able to tell if this is an actual case of nuclear sclerosis or if it is a case of cataracts. While dogs affected by nuclear sclerosis will exhibit a typical bluish haze on their lens, a dog suffering from cataracts will typically exhibit various white chunks that appear as crushed ice.

The lens of a dog with healthy normal eyes will exhibit a greenish tint when shined upon with a flashlight in a dark room (reflection from the tapetum), whereas the lens of a dog with cataracts are too dense, and therefore, the light will not be able to go through the retina and cause this normal refection.


Nuclear sclerosis does not require any treatment. Vision is not affected until the dog grows older, and there may be signs of blurred vision. Cataracts, on the other hand, require surgery to remove the cataracts and prevent blindness.

While gender or breed seem to not play a particular role in the development of this condition, it appears, however, that exposure to sun rays may increase or expedite the occurrence. Nuclear sclerosis ultimately cannot be prevented as it is a pretty normal sign of aging.

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.


shalini on October 30, 2009:

good artical......

Related Articles