Inflammation of the middle ear structures (otitis media) is usually caused by an extension of infection from the external ear canal or by penetration of the eardrum by a foreign object. Inflammatory polyps (see Ear Disorders of Cats: Inflammatory Polyps) are also a common cause of otitis media in cats. The spread of infection through the bloodstream to these areas is also possible, but it is rare. Inflammation of the middle ear may lead to inflammation of the inner ear structures (otitis interna). This can in turn lead to loss of balance and deafness. In general, otitis media and interna are more serious than otitis externa, and their effects on the ear may not be reversible.
If your cat is having problems with balance, walking, or jumping, you should suspect a middle ear problem and take your pet in to the veterinarian promptly. A pus-filled inflammation of the outer ear may also signal inflammation of the middle or inner ear.
The diagnosis, treatment, and preventive care for otitis media and interna in cats is very similar to this condition in dogs (see Ear Disorders of Dogs: Otitis Media and Interna in Dogs).
Last full review/revision July 2011 by T. Mark Neer, DVM, DACVIM; Michele R. Rosenbaum, VMD, DACVD; Patricia D. White, DVM, MS, DACVD