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Ear problems are common in cats and can affect the pinnae (the ear flap that sticks up from the head), the ear canal, or the inner parts of the ear. The most common diseases are those that affect the outer pinna and ear canal.

Diseases affecting the ear

• Wounds and trauma: Wounds affecting the ear are commonly a result of fighting with other cats with damage being sustained from bites or claws. Other causes of ear injury include road traffic accidents or dog attacks. Many of these wounds may also have infection present and sometimes a swelling with an abscess may develop. It is important that all injuries and swellings to the ear are checked by a vet to determine what treatment may be necessary.

• Aural haematoma: An aural  haematoma is a blood-filled swelling of the pinnae due to rupture of a small blood vessel under the skin. It results in haemorrhage and blood accumulation between the skin and the cartilage. This condition is seen more commonly in dogs than cats and is usually caused by some form of trauma to the ear. In some cases aural haematomas are caused by the cat shaking or scratching at their ear violently. Marked swelling usually develops rapidly and the condition can be quite painful. Your vet will need to determine both the underlying cause of the irritation to the ear and also determine the best treatment for the haematoma which may include surgery in some cases. Often there is some fibrosis and scarring after a haematoma forms that can cause slight deformity of the ear (a ‘cauliflower ear’ appearance).

• Solar dermatitis: In Perth we have a very high risk of skin damage due to ultraviolet (UV) sunlight exposure and these same risks apply to our cats especially those with white ears. Early UV skin damage is called solar dermatitis. This starts with inflammation of the ear tips where the skin appears pink and scaly but as the condition progresses it may become crusted, ulcerated and may bleed. If left untreated, this condition may progress to squamous cell carcinoma (a malignant skin tumour). Surgical removal of the ear tips is the treatment of choice and the end appearance is usually very acceptable and has no detrimental effect on the cat. To reduce the risk of this condition, it will help to:
  • Avoid exposure to sunlight to your cat during the height of the day (e.g., 10.00am-15.00pm)
  • Use a cat-safe sun-block on the ears and nose such as Filta-bac (available from our reception)

• Ear mites, parasitic otitis, Otodectes cynotis: There are several types of ear mites that can live in cat’s ears, but the most common is Otodectes cynotis. These tiny, eight-legged parasites feed on the wax and oils in a cat’s ear canal and can be spread from one cat to another. An individual mite has an approximate three-week life cycle and is only just visible to the naked eye as a dirty white speck. Some cats can show minimal signs of ear mite infection however most will produce a strong allergic response to the mites causing irritation and inflammation of both the external and internal ear canal. Infection usually produces a characteristic dark crumbly discharge and in the most severe cases, a cat’s ear canal can become entirely obstructed by this coffee ground-like debris. Prolonged or severe cases can develop secondary bacterial and yeast infections. Diagnosis and treatment is usually straightforward, but may not necessarily involve using ear drops. Some ‘spot-on’ insecticides such as selamectin are very effective against ear mites and direct application to the ears may not be required. In some cases, careful cleaning of the ear may be needed, but this should be done by your vet, and may require an anaesthetic to be carried out safely.

• Bacterial ear infections: Bacterial otitis often occurs secondary to some other ear problem such as ear mites, a foreign body, trauma, food hypersensitivity, or other allergies, although sometimes an infection will occur with no obvious predisposing cause. Fungal infections (with yeasts) may also be present. Pus is usually evident in the ear canal, there may be a bad odour, and the cat will be uncomfortable. Your vet will need to carefully examine your cat or kitten to search for underlying causes and may need to administer a short anaesthetic to fully examine and/or clean the ear. Antibiotics will be required and your vet may give you antibacterial ear drops to administer. Don’t be tempted to buy ear drops from a pet shop or elsewhere as these will not be as effective as the treatment your vet can give and may even be dangerous, especially if there is any damage to the tympanic membrane.

• Foreign bodies: Although much more common in dogs than cats, occasionally a foreign body such as a grass seed or blade of grass will get stuck in the ear canal. This usually causes sudden onset of pain, scratching at the ear, holding the head to one side, etc. Your cat will often need a short anaesthetic to safely remove the foreign body without causing any damage.

• Polyps: Benign polyps may develop within the middle ear or the eustachian tube of cats. Cats of any age may be affected, but it is most commonly seen in young adults. These are benign inflammatory masses, but the underlying cause remains unknown. The polyp may grow in the nasopharynx (throat) and/or the middle ear of the cat, and if in the middle ear it may eventually cause the ear drum (tympanic membrane) to rupture and be present in the external ear canal.

• Tumours of the ear canal: In older cats especially, tumours may develop in the skin lining the ear canal. These growths may be benign polyps or tumours, but in many cases are malignant (most commonly ceruminous gland adenocarcinoma). These often appear as multiple small nodules, frequently with secondary infection (which may be the most obvious sign). Your vet will need to examine the cat, and may take small biopsies under an anaesthetic to determine the cause and the most appropriate treatment. In some cases surgery may be needed. Some cats required advanced imaging such as CT prior to any surgery to assess the full extent of the disease.

• Infection of the middle ear: This is seen more commonly in kittens than adult cats and usually results from infection spreading up the eustachian tube (the small tube that connects the nose to the middle ear). This may occur as a complication from upper respiratory infections. In cases of suppurative otitis externa, if the tympanic membrane is compromised then the infection may readily spread to affect the middle and inner ears also.

Diagnosis and investigation of ear disease in cats

The investigation and management of ear disease will vary from one cat to another. Initially your vet will use an otoscope to examine the inside of your cat’s ear canal in addition to performing cytological examination of ear discharges under the microscope. In many cases thorough examination of the ear canal will be needed to be performed under anaesthesia. In addition to cytology there may be other laboratory tests that are required such as skin scrapings, hair analysis and bacterial and/or fungal culture.

If your vet suspects an underlying allergy, they may need to perform a thorough allergy work up which may include an appropriate flea control program, an elimination diet trial and even intradermal skin testing.

For cases with evidence of middle ear disease, or if your vet suspect a tumour or polyp, advanced imaging such as CT or MR scans can be very helpful to characterise the problem.

Treatment

Treatment will depend on the underlying cause. If the ears have infection or build-up of debris, gentle cleaning by your vet may be required. This is often performed under a general anaesthetic to avoid causing discomfort. Your veterinarian may also prescribe medicated ear drops or an antibiotic to resolve infections.

In some cases, surgery may be required, which may include a procedure called ‘bulla osteotomy’ where part of the bony wall of the middle ear is removed so that a mass such as a polyp can be successfully removed completely.

See the short video below on how to administer ear drops to your cat. 

Disclaimer: Please note that the information provided on this page does not replace the advice of your veterinarian. If you are concerned about your cat’s health in any way, we strongly recommend you seek veterinary advice.