Cholesteatoma is a benign growth of skin in the middle ear or mastoid that can lead to infection and more serious problems involving the brain and facial nerve. It is not a cancer condition but is important because it can lead to serious complications such as permanent deafness and life-threatening illnesses such as meningitis and brain abcesess.
The cause of the cholesteatoma is not fully understood. It is thought that skin cells from the lining of the ear canal get trapped in the middle ear. Skin cells, including those that line the ear canal, normally multiply regularly to replace those that have died. Usually these skin cells flake off. The dead cells are trapped too and build up. This build-up of dead skin cells over time is what forms the cholesteatoma.
Types of Cholesteatoma
and Congenital cholesteatoma grows behind the eardrum from birth.
and Acquired cholesteatoma develops later, usually in adults. This is often as a result of a chronic or recurring ear infection. The infection causes a blockage of the Eustachian tube. This is the tube that connects the middle ear to the back of the nose and throat. The blockage creates a negative pressure that draws the eardrum inwards. This can result in a small pocket forming, usually at the very top of the eardrum. In this pocket some skin cells collect, get trapped, but continue to multiply to form the cholesteatoma. The pocket is too deep to allow the dead skin cells to escape, so the cholesteatoma gradually expands.
Symptoms
Cholesteatoma is usually unilateral. The most common initial symptoms are a smelly discharge from the ear, and some hearing loss. You are also likely to have had previous problems with ear infections. Other symptoms that may occur include hearing loss and vertigo.
Complications
Erosion of the ossicles (bones) behind the eardrum can lead to a conductive hearing loss. The bone over the facial nerve can also be destroyed, and a facial paralysis can result. The inner ear, composed of a bony labyrinth, can also be partially destroyed. This can lead to sensor neural hearing loss and dizziness. The infection can also spread into the veins carrying blood from the brain to the heart. The sigmoid sinus can get thrombosis. The infection can also spread to the covering of the brain and cause meningitis. In rare circumstances, a brain abscess can occur.
Facial Nerve Paralysis with Ear Disease
Facial nerve paralysis can be seen in patients who suffer from acute and chronic ear infections (otitis media). Facial paralysis that occurs suddenly during an acute ear infection implies inflammation of the nerve. This tends to occur in infants and young children, because the bony canal surrounding the nerve is not as insulated from the middle ear space as it is in adults. Ordinarily, prompt treatment of the infection, that sometimes includes putting a hole in the ear drum (myringotomy) to remove the infected contents, leads to recovery of the nerve.
Sudden facial paralysis in the setting of chronic ear disease suggests damage caused by expanding cholesteatoma. When sudden facial paralysis occurs in the face of known chronic ear disease, prompt surgical exploration with evacuation of disease and nerve decompression usually results in good recovery of function.
Diagnosis
Otoscopy and Microscopic examination
Audiometry (hearing tests) may show deafness or hearing loss and are usually performed in a hospital clinic.
Swabs of the ear discharge may also be taken. The discharge often contains a bacterium Pseudomonas which is responsible for the smell.
CT scans might be needed to see the extent of the damage caused by the cholesteatoma, and to plan further treatment.
Treatment-Surgery
Surgery removes all of the diseased areas, including the cholesteatoma itself. Virtually all cholesteatomas should be removed by surgery.
Mastoidectomy
In the canal wall–down (open) procedure, the posterior canal wall is removed. A large meatoplasty is created to allow adequate air circulation into the cavity that arises from the operation. Canal wall–down operations have the highest probability of permanently ridding patients of cholesteatomas.
