However, hearing loss is not always permanent. Impaired sound conduction from discharge or a narrowed canal differs from inner ear damage. The original inflammatory cause may also be something other than infection, with bacteria or yeasts multiplying secondarily.
When to see a vet urgently
Contact a vet promptly if your cat develops any of the following:
- Unsteadiness, falling, involuntary eye movement or a sudden head tilt.
- Drooping on one side of the face or difficulty blinking.
- Severe ear pain, difficulty eating or obvious deterioration in general condition.
- Copious pus-like or bloody discharge and rapidly worsening swelling.
Do not forcibly clean a painful ear before examination. You can find a vet near you.
Overview
Otitis means inflammation of the outer, middle or inner ear. When chronic, it causes tissue thickening and tumour-like overgrowth, narrowing and distorting the ear canal. This is described as deforming otitis. It is rarer in cats than dogs, but risk increases substantially with chronic infections.
The ear canal belongs to the outer ear. Behind the eardrum lies the middle ear, while the deeper inner ear contributes to hearing and balance. The location of inflammation is investigated because external canal narrowing alone does not establish whether deeper structures are affected.
Chronic inflammation can cause skin and gland overgrowth, scarring and sometimes cartilage mineralisation. The canal then no longer clears normally, and medicines have difficulty reaching inflamed surfaces. This sustains a cycle in which removing discharge alone may provide temporary relief without correcting the whole problem. Tumour-like thickening does not itself mean cancer.
Causes
The main causes of chronic otitis with structural changes in cats include:
- chronic outer or middle ear inflammation
- bacterial or fungal infections
- parasites, including the ear mite Otodectes cynotis
- allergic reactions, including atopic dermatitis and food allergy
- foreign bodies in the ear canal
- ear tumours
- injuries and ongoing mechanical irritation
Otodectes cynotis is an ear mite, not a flea. Ear mites are a common cause of ear symptoms, particularly in young cats. A polyp or tumour preventing ventilation and drainage may also underlie chronic changes. Persistent symptoms in one ear therefore warrant investigation of a local obstruction too.
Infection may sustain inflammation even if the original trigger was an allergy, parasite or structural change. Treatment therefore distinguishes the underlying cause, predisposing conditions and factors maintaining chronic disease. Trying another antimicrobial alone does not always resolve recurrent otitis.
Risk factors
The condition occurs more often in cats:
- whose otitis is not treated promptly
- with weakened immune systems
- prone to allergic reactions
- living in damp, dirty conditions
- that are older and have chronic diseases
Information on the independent effects of every factor listed in cats is limited. Moisture and irritation can worsen the ear's condition, but a dirty home, old age or suspected immunodeficiency alone does not establish the cause of narrowing. Ear symptoms are also assessed in cats without a known allergy or other long-term disease.
Main symptoms
Symptoms of chronic otitis with structural changes include:
- thickened ear canal walls
- narrowing or complete blockage of the canal
- persistent ear discharge, which may be pus-like, watery or foul-smelling
- ear itching and scratching
- head shaking or tilting to one side
- reduced hearing or complete hearing loss
- pain when the ear is touched
Behaviour may change at home too: your cat may avoid head stroking, hide or resist opening its mouth. Pain can interfere with chewing. Smell and discharge indicate an ear problem needing investigation, but do not identify bacteria, yeast or another cause on their own.
A head tilt and impaired balance can be associated with inner ear or nervous system disease. They are not regarded simply as consequences of itching. Your cat may need help with movement and feeding, but the cause still needs investigation.
Complications and consequences
Without treatment, chronic otitis with structural changes can lead to:
- permanent hearing loss
- infection spreading to the middle and inner ear
- neurological complications, including facial nerve damage and balance problems
- abscess formation
- removal of the ear canal, called total ear canal ablation
Ear canal removal is a treatment for severe irreversible disease, not an inevitable consequence of inflammation. The decision depends on canal changes, a possible tumour and whether medical treatment is practical. The main aim is to eliminate pain and continuing inflammation.
Facial nerve damage can impair eye closure, so the eye's surface also needs assessment. Inner ear damage may leave balance or hearing changes after infection settles. However, an individual cat's prognosis cannot be inferred solely from the amount of visible discharge.
Diagnosis at the vet
Diagnosis uses:
- otoscopy to examine the ear canal
- discharge cytology and bacterial culture
- head X-rays or CT to assess the depth of changes
- assessment of general condition and concurrent diseases
Samples before treatment selection
An otoscope assesses the canal surface, discharge, possible masses and eardrum. Severe pain or narrowing may prevent adequate examination while awake. Sedation or general anaesthesia permits safer inspection, sampling and any necessary flushing. If the eardrum cannot be seen, it cannot be assumed intact.
Cytology looks for inflammatory cells, bacteria and yeasts. Culture is particularly useful in recurrent or severe bacterial infections, with susceptibility testing guiding medicine selection. A different sampling site may be needed if middle ear infection is suspected: an outer ear result may not reflect deeper inflammation.
CT shows changes in the ear canal and bony middle ear structures and helps plan surgery. MRI may be considered, particularly for deeper soft tissue or neurological changes. Ordinary X-rays alone are not always enough to exclude middle ear disease. Abnormal tissue may need sampling to distinguish a tumour from inflammation.
Treatment and recovery
When the canal still allows topical treatment
Treatment may include veterinary cleaning, pain relief and a medicine selected to target parasites, bacteria or yeasts found. Medication can also reduce inflammation and swelling. The choice depends on eardrum condition, inflammation location and other diseases.
Previously suitable ear drops are not automatically safe in a new situation. Some substances can damage hearing or balance if they pass through a ruptured eardrum. Do not start old ear medicines or strong cleansers on your own. Do not insert cotton buds or other objects into the canal.
At home, clean only as demonstrated by the vet and with a suitable product. If handling increases pain or unsteadiness develops, contact the practice. An underlying allergy or parasite infestation is also treated so the cause of recurrence does not remain.
When is surgery considered?
An irreversibly scarred, mineralised or obstructed canal may need surgery. Total ear canal ablation (TECA) removes the diseased canal. The bony middle ear cavity may be opened and cleaned at the same time. The external ear flap can usually remain.
Important nerves and blood vessels run through the surgical area. Possible complications include altered facial nerve function, wound problems and ongoing inflammatory discharge. Risks and expected hearing are assessed beforehand. Hearing that is already severely impaired may not change noticeably to the owner, but surgery is not promised to restore it.
After discharge, follow pain relief, wound care and review instructions. A collar may prevent wound scratching. Report new swelling, discharge or difficulty closing the eye. Even successful surgery requires agreed follow-up, and the other ear is assessed separately when needed.
Prevention
To reduce the risk of chronic otitis with structural changes:
- treat acute otitis promptly and monitor its course
- check your cat's ears regularly, particularly in susceptible breeds such as British Shorthairs and Persians
- maintain ear cleanliness and prevent accumulated wax and dirt
- control allergies and skin diseases
- seek veterinary care at the first signs of inflammation
A specific predisposition of British Shorthairs and Persians to this narrowing cannot be treated as a certain general rule. Symptoms in every cat are addressed regardless of breed. A healthy ear generally does not need vigorous or frequent cleaning, which can irritate its surface. The need and method depend on findings.
What it means for owners
Chronic otitis with structural changes is a serious, long-term disease that reduces quality of life and can cause complete hearing loss. Remember that every prolonged ear infection needs attention and treatment. Early treatment of ordinary otitis prevents progression to this form.
Early treatment can reduce the risk of chronic disease and permanent changes, but cannot reliably prevent them in every case. Response and canal condition are checked even if smell or scratching improves before treatment ends. Prognosis in prolonged disease also depends on controlling the original cause.
This material is for information and does not replace veterinary advice. Seek veterinary attention immediately when the first signs of illness appear.
Frequently asked questions
Is chronic otitis with structural changes the same as an ear tumour?
No. Chronic inflammation can thicken and narrow the canal without cancer. However, a tumour or polyp may also underlie blockage and recurrent infections. Abnormal tissue is sampled when needed.
Will a cat's hearing return after treatment of ear inflammation?
It depends on the location and type of damage. Restoring sound conduction blocked by discharge differs from permanent inner ear damage. Treatment primarily aims to remove pain and control disease; hearing recovery cannot be promised in advance.
Can a completely blocked ear be treated with drops?
A topical medicine alone may not adequately reach diseased tissue when the canal is permanently narrowed. Investigations establish whether medication and cleaning remain possible or surgery is needed. Do not try to force open or flush a painful ear at home.
This article is for general information only and is not a guide to treatment. If you notice the first signs of illness, contact your vet.
Paw4care editorial team
Sources
- Otitis Externa in Animals, Merck Veterinary Manual, accessed 2026-11-03.
- Otitis Media and Interna in Animals, Merck Veterinary Manual, accessed 2026-11-03.
- Instructions for Ear Cleaning in Cats, VCA Animal Hospitals, accessed 2026-11-03.
- Otitis Externa, American College of Veterinary Surgeons, accessed 2026-11-03.
- Total Ear Canal Ablation and Bulla Osteotomy (TECA-BO), VCA Animal Hospitals, accessed 2026-11-03.
- Inner Ear Infection (Otitis Interna) in Cats, VCA Animal Hospitals, accessed 2026-11-03.