Posted: July 3, 2009, 3 a.m. EDT
Q: This question concerns my son's cat, who I have taken in. He used to have two regular ears; however, his right ear is now all crumpled up. At first I though he got in a fight with one of my other cats, but there is no evidence of that (no blood, no lacerations). The ear doesn't seem to hurt him; I can rub it and he doesn't pull away. It is really weird. If you look at him full on, it is almost as if he doesn’t have a right ear. The other ear is fine. What do you think happened to him?
A: I suspect that your cat did suffer some kind of trauma to that ear, resulting in a condition called an aural hematoma. This is a condition in which a small blood vessel in the ear is damaged and begins to bleed. The blood accumulates between the inside and the outside layer of skin of the ear, making the ear puffy, like a little pillow. The most common cause of trauma is excessive scratching of the ear due to ear mites or an infection.
Large aural hematomas are easy to spot, because the accumulated fluid is heavy and weighs the ear down, causing a lopsided appearance to your cat’s head. I can see, however, where a smaller, more subtle hematoma might be missed by an owner. If untreated, the fluid in the ear eventually gets reabsorbed; however, fibrin in that fluid remains in the space where the fluid was, and as the fibrin contracts, it will cause distortion of the ear, resulting in a crumpled appearance.
I recommend that you have your cat examined by your veterinarian to see if an ear infection, or an ear mite problem, is the inciting cause of your cat’s crumpled ear.