Why is the dark spot on my cat's eye growing and spreading over time?

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.

It is not uncommon for cats to develop brown or black spots on the iris. A pigmented area on the iris can be benign or malignant, and differentiating them is sometimes difficult. My guess is that these spots are what we call iris nevus. These are benign (like freckles). Since she has so many, this would be called iris melanosis. Iris melanosis is classified as benign, but in time, it may progress to a malignant melanoma. Although melanomas are rare in cats, the eye is the most common site for it to show up. The first hint that this could be melanoma is rapid growth. If you know the spot(s) is getting larger quickly, that is a warning sign. If the shape of the pupil has become deformed as it dilates and constricts, that is another potential red flag. I suggest you have Dixie examined by your vet to get a diagnosis. She needs a thorough exam with a ophthalmoscope. Hope this helps. Best wishes.

Brittany is beautiful! It is common that cats will have color changes in the iris (the colored part of the eye) that will appear darker or almost like a freckle. If your vet has examined Brittany and told you that it is nothing to worry about, then I would just monitor it. It should not change appearance over time or appear to be getting thicker. If that happens, then I would have your veterinarian examine it again. Good luck! I hope that was helpful and answered your question. Thanks for using Petco Pet Education Center, formerly Petcoach.

Hello. In terms of your cats, the first one with the eye getting bigger than the other really needs to be seen by a vet as soon as possible. Glaucoma is a very serious condition and in order to not lose vision in the eye you want to treat it right away. This is also a very painful condition. The other cat, with a bump that looks like a zit, could just be a sebaceous cyst. It is always best to get it checked out, however if it isn't growing or changing, or causing your cat issues, you can monitor it for now and have it seen at your next appointment with your vet. Good luck with your two cats!

It looks like Memo could have changes to the iris due to anterior uveitis or inflammation in the eye. This can cause the pupil to become smaller and the iris to change colors. It’s also possible that Memo has a growth on this eye. I would recommend seeing your veterinarian so they can examine Memo’s eye in person. They may want to check his eye pressure.

Certainly. The brown pigment of his eye appears to be an eye freckle. These are quite common in pets and are bengin, so no worries. Thanks for visiting Petco Pet Education Center, formerly Petcoach and good luck moving forward with Sir Henry. Take care! : )

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.