Deafness in Cats

Loss of Hearing in Cats

Deafness can be classified as either a complete or partial hearing loss. If your cat is deaf at birth (congenital), it will be apparent to you when the cat is still at a young age. Cats that have white hair and blue irises appear to be particularly prone to congenital deafness. Some of the breeds that tend to be at highest risk for congenital deafness are white Persians, white Scottish folds, Ragdolls, white cornish rex and Devon rex, white oriental shorthair, white Turkish angora, white Maine coone, and white manx.

 

Symptoms

• Unresponsive to everyday sounds
• Unresponsive to its name
• Unresponsive to the sounds of squeaky toys
• Not woken by a loud noise

Causes

• Conduction (sound waves do not reach the nerves in the ear)
  • Inflammation of the outer ear and other external ear canal disease (e.g., narrowing of the ear canal, presence of tumors, or ruptured ear drum)
  • Inflammation of the middle ear
• Nerve
  • Degenerative nerve changes
  • Anatomic disorders — poor development (or lack of development) in the part of the ear that contains the nerve receptors used for hearing; the condition leads to fluid buildup in specific areas of the brain and damages the part of the brain involved with hearing
  • Tumors or cancer involving the nerves used for hearing
  • Inflammatory and infectious diseases — inflammation of the inner ear; inflammatory masses that develop in the middle ear or eustachian tube
  • Trauma
• Toxins and Drugs
  • Antibiotics
  • Antiseptics
  • Chemotherapy drugs
  • Medications to remove excess fluid from the body
  • Heavy metals such as arsenic, lead, or mercury
  • Miscellaneous — products used to break down waxy material in the ear canal
• Other risk factors
  • Long-term (chronic) inflammation of the outer, middle, or inner ear
  • Certain genetic conditions, such as white coat color

Diagnosis

You will need to give a thorough history of your cat's health, onset of symptoms, and possible incidents that might have preceded this condition, including any drugs that may have damaged the ear or caused a chronic ear disease. Early age onset usually suggests birth defects (congenital causes) in predisposed breeds.

On the other hand, brain disease is a slow progressive disease of the cerebral cortex, usually caused by senility or cancer – causing the brain to be unable to register what the ear can hear. Bacterial cultures and hearing tests, such as sensitivity testing of the ear canal, may also be used to diagnose any underlying conditions.

Treatment

Unfortunately, congenital deafness is irreversible. But if the loss of hearing is caused by an inflammation of the outer, middle, or inner ear, medical or surgical approaches may be used to attempt a reversal of the deafness. These two methods, however, are dependent on the extent of an existing disease, results from bacterial cultures, sensitivity test results, and X-ray findings. Conduction problems, in which sound waves do not reach the nerves for hearing, may improve as inflammation of the outer or middle ear are resolved. In some cases hearing aids are an option; they have been used successfully with some animals.

Living and Management

Your cat's physical activity should be reduced to avoid any possible injuries. That is, a deaf animal cannot hear the approach of a car or another animal, so it will need to be limited from outdoor activities. Your cat's immediate indoor environment may also need to be controlled for its own safety and protection, and household members and guests will need to be cautious of alarming or unintentionally hurting the cat.

If your cat is diagnosed with an ear disease, your veterinarian may need to see your cat regularly for treatment, or until the condition is resolved.

Image: Maria Sbytova via Shutterstock

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