Why is my old cat's pupil jagged, dilated, affecting night vision?

There is anisocoria (the two pupils are unequal in size) and possibly ptosis of the upper eyelid (the eyelid cannot open normally) on the left side (where the pupil is bigger). There are many causes that can provoke this presentation: -Corneal injury such as an ulcer. -Disease or injury to the brain or to the nerves running to the affected eye, such as Horner’s syndrome. -Glaucoma, a disease in which there is increased pressure within the eye (the pupil in the affected eye will be dilated). -Uveitis, or inflammation of the interior of the eye (the pupil in the affected eye will usually be constricted). -Retinal disease. -Scar tissue formation between the iris and the lens (called posterior synechia), a condition that may develop following uveitis. -Iris atrophy (a decrease in the amount of tissue within the iris) usually a degenerative change associated with aging. -Congenital defect of the iris, in which the iris tissue does not develop properly. -Cancer within the affected eye. -Spastic pupil syndrome - a syndrome that may be associated with feline leukemia virus infection. -Other infectious diseases such as feline immunodeficiency virus or toxoplasmosis. Unfortunately is difficult to be more specific than that and a clinical examination at your local veterinarian is essential to confirm these clinical suspicions and treat appropriately. Antibiotics may be needed. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. If this answer was helpful please let us know, this will be used to improve our service!

The main thing I would be worried about and cats that have persistently dilated pupils are issues with the right now which is the covering on the back of the eye. Middle-aged to older cats can develop high blood pressure as well as kidney issues that can cause the retina to be damaged, leading to blindness and persistently dilated pupils. I would recommend having your veterinarian examine Athenais's eyes to make sure everything's normal and there's no underlying disease that needs to be addressed.

What a beautiful girl! It does look like her left eye and pupil are larger than the right. There could be a few reasons for this including increased pressure (glaucoma) or a mass behind the eye that pushes it forward and makes it appear larger. I would strongly recommend an examination by a veterinary ophthalmologist to fully evaluate her eye and her vision to see what can be done for her.

I would recommend that Monet see a veterinarian. Sudden onset of blindness and dilated pupils can be secondary to high blood pressure in older cats. They can suffer from hyperthyroidism or a heart disease called hypertrophic cardiomyopathy. Both of these geriatric cat problems can cause these changes with her eyes. Thank you for using Petco Pet Education Center, formerly Petcoach.

That new pigment around Butter’s pupil is concerning for inflammation of the iris or melanoma. Cats can get uveitis (which is basically inflammation of the internal eye structures) for many different reasons. Hyperthyroidism can also sometimes change the pigment. Melanoma is a cancer that can affect the eye of a cat at any age. I recommend to make an appointment with your veterinarian. That will at least get you started on the right path. Fingers crossed it’s nothing serious! Please post again with any further questions.

There are a couple of possibilities here for the changes to Creo's iris. One is iris atrophy, which is a normal aging change. This can often result in pigment change and a "moth-eaten" appearance to the iris or an irregular iris border. Another would be a uveal cyst, which is a darkly pigmented circular lesion that can be attached to the iris. Both of these are generally benign. If you notice any changes in Creo's vision, changes to the eye, or signs of pain (squinting, redness, swelling, etc.), have him re-evaluated by your vet just to be safe.

I am not quite sure. It may be that you are seeing a severely dilated pupil. Some disease can cause hypertension, which if unmanaged for some time, can cause damage to the retina which causes a dilated pupil and blindness. I would recommend that you have Tiger examined by the vet. They can look at the eye and do bloodwork and blood pressure testing to see what is going on. Some of these cases can be reverse, while others the blindness will be permanent.