Her dog behaved completely normally the morning of this incident. She came home that afternoon and called her dog and it did not greet her as usual. She walked into the bedroom, found him lying on the bed and called him again and he did not respond. She became alarmed at this lack of response and walked up to him and put her hand on him. He responded with a startle reaction at her touch but then jumped off the bed and seemed completely normal.
Her dog had no history of ear problems and absolutely no other symptoms of ear disease- no head tilt, no neurologic signs, no odor. She took him to her veterinarian and he could find nothing wrong with his ear canals and had no explanation for his sudden deafness.
There are very few causes of sudden deafness in dogs and it is a rare event, especially in a young dog. Most of these causes have other accompanying symptoms.
Otitis Externa (Ear infections)
Ear disease can cause deafness if both tympanic membranes (ear drums) are completely occluded, but is almost always accompanied by discharge, odor, discomfort and scratching at the ears.
Some medications can cause temporary or permanent sudden hearing loss in dogs but is also generally accompanied by other neurologic signs such as a head tilt to one side, stumbling, unsteady gait (ataxia) or walking in circles. Some antibiotics and ear cleaning solutions have caused this type of deafness.
Very loud noises can cause temporary or semi- permanent hearing loss (usually by rupturing the ear drums). Gunfire, fireworks, very loud alarms or music can be responsible for this type of hearing loss, but generally the animal recovers eventually.
Compensation or Selective Hearing Loss
In my 22 years of practicing medicine it is much more common for me to see older animals that have been slowly losing their ability to hear but have compensated for it in a variety of ways until one day their compensatory mechanisms (picking up on vibrations, smell, habits of their owners, etc) no longer works for them and they can no longer detect any sounds at all. This often appears as sudden deafness but is truly hearing loss occurring over time.
Animals adapt very quickly to hearing loss and learn to use other methods of detecting what is going on around them and don’t seem to be bothered by their inability to hear. But then, they don’t seem to be bothered by most of what bothers us humans do they? Do you have any other causes of sudden hearing loss that you know about?