You have lovingly gazed into your senior pet’s eyes a thousand times and no doubt know every detail by heart. Any change, such as cloudiness or redness, is alarming since you know that some eye problems can affect your pet’s precious vision. Several eye conditions—some concerning, some not—could be responsible for the changes in your senior pet’s eyes. If you see an eye abnormality, schedule an appointment with your family veterinarian, who will likely diagnose one of the following conditions.

Glaucoma in senior pets

Your pet’s eyes are filled with fluid that is continually produced and drained to maintain a steady pressure. If something interferes with drainage, such as degeneration of the outflow canals, fluid accumulates, and the pressure builds. Increased intraocular pressure is excruciating, and your pet can experience a migraine-level headache. Other signs include:

* Redness

* Enlarged or bulging eye

* Cloudy cornea

* Pawing at the eye

* Decreased appetite

* Behavior changes, such as hiding, sleeping more, and shying away from being touched near the head

Glaucoma is a medical emergency since increased pressure can damage your pet’s retina and cause blindness. Any redness can indicate glaucoma, so ensure your pet’s eyes are checked at the first sign of discomfort. Glaucoma can be medically managed, but many affected pets eventually become blind and may require eye removal to alleviate chronic pain.

Cataracts in senior pets

A cataract, an opacity in your pet’s usually transparent lens, appears as a grey or light blue cloudiness. Your pet’s lens helps focus light rays on their retina to produce a clear image and allows their eye to transition between close-up and distance vision. Light rays can still enter the eye if an opacity is present, but your pet will not see a clear image. A cataract can affect the entire lens, which can cause blindness or only part of the lens. Cataracts most often develop in genetically predisposed dog breeds, such as poodles, golden retrievers, and Siberian huskies, although some systemic diseases, such as diabetes, can also contribute to their formation. 

Fortunately, if your pet’s other eye structures work correctly, a cataract can be surgically removed and replaced with a lens implant. Although expensive, the surgery can restore your pet’s vision and provide a better quality of life. 

Progressive retinal atrophy in senior pets

Your pet’s retina is a layer of photoreceptors (i.e., rods and cones) and nerve cells lining the back of the eye. When light stimulates the photoreceptors, they send an impulse through the optic nerve to the brain, which interprets the image. Progressive retinal atrophy (PRA) causes the photoreceptors to degenerate slowly, resulting in irreversible blindness. Rods are typically affected first, causing night blindness, which pet owners may not recognize. Only when cones start to degenerate, and daytime vision declines do pet owners notice a problem. PRA causes no apparent changes to a pet’s eyes, so you will not notice any abnormalities. Unfortunately, PRA causes progressive blindness, and no cure is available.

Lenticular sclerosis in senior dogs

Lenticular sclerosis, or lens hardening, appears in your pet as a cloudy lens. Lenticular sclerosis is a regular aging change typically observed in dogs over eight years old and does not affect their vision. Since cataracts also cause lens cloudiness, lenticular sclerosis is often mistaken for this more severe condition. A thorough eye exam can help your family veterinarian differentiate between cataracts and lenticular sclerosis.

Iris atrophy in senior cats

Your cat’s iris, the colored part of the eye surrounding the central pupil, comprises a thin sheet of muscular tissue. The iris muscles contract and relax to allow your cat’s pupil to change size in response to different light levels. Over time, your cat’s iris may degenerate, and their pupil enlarges. While iris atrophy does not cause blindness, your cat may be unable to constrict their pupil to limit light entry adequately, and they may be more sensitive to bright light.