A: I get this question a lot. Hearing loss in older cats and dogs does occur as a normal part of aging in some pets, similar to the situation in some older people. The cells of the inner ear start to degenerate and sound transmission via the auditory nerves decreases. A special test called a brain evoked auditory response test can be performed to confirm deafness, but in most cases, simply observing the pets response to various noises is enough for owners and veterinarians to determine if hearing loss is present.

Having said all of this, I would first make sure that Jeff does not have any diseases of the external ear. If his ear canals are full of debris, simply cleaning the ears (while the pet is under anesthesia) will restore his hearing.

If his ears appear normal on physical examination, there is one other possibility. Some older pets with cognitive disorder will show hearing loss as one of their signs. Supplying these pets with choline (I use Cholodin) and antioxidants (I like Proanthozone) can help these pets. Otherwise it may be that Jeff's hearing loss is simply related to aging. There are hearing aids for pets, but most owners choose to live with (and keep inside) pets with hearing loss.

By Dr. Shawn Messonnier, The Dallas Morning News
http://www.fortwayne.com/mld/newssentinel/living/13500160.htm