Conductive deafness due to Chronic Ear infection
Anatomy and Physiology of the Ear Click here
Chronic Suppurative Otitis Media (SAFE TYPE)
Chronic Otitis Media is chronic infection of the middle ear cleft, can be of types:
(>3 months duration)
1. Perforation of Tubo-tympanic or Attico – antral type.
2. Chronic non-suppurative otitis media ego Serous otitis media.
3. Chronic specific otitis media e.g. following tuberculosis.
I. TUBOTYMPANIC DISEASE (SAFE TYPE)
i. Residue of an acute otitis media infection during childhood.
ii. Repeated infections from the eustachian tube.
Perforation – Usually in the form of a central perforation situated exclusively in the pars tensa.
The ossicular chain often remains intact and middle ear mucosa is pink and edematous.
1. Discharge – is mucoid, copious and non foul smelling. It becomes profuse during an upper respiratory infection.
2. Deafness – is conductive in type. Degree varies with the position and size of perforation.
1. Aural toilet – Is performed meticulously under direct vision, preferably suction and irrigation done under the operating Microscope.
2. Bora-spirit – Ear drops are advised only during active discharge.
3. Focus of infection – Are treated medically or surgically e.g. tonsillitis, sinustitis etG.
4. Removal of polypi or granulation tissue – if present in the middle ear.
5. Chemical cautery – Using 50% Trichloro acetic acid for smaller perforations ( < 65% area if tympanic membrane).
6. A Myringoplasty operation – May be required for a persisting perforation.
Anatomy and Physiology of the Ear Click here
Perforation of the Ear Drum (Tympanic membrane)
A perforated eardrum is a hole or rupture in the ear
drum, the thin membrane that separates the ear canal
and the middle ear.
The Ear drum can perforate from infection or trauma.
An Infective perforation of the eardrum
Starts with infection from the nose after a head cold travelling up the Eustachian tube to reach the middle ear to promote an infection in the middle ear. Pus builds up in the middle ear behind the ear drum with pressure causing severe throbbing pain and breaks through a weak point in the ear drum leaving a perforation with a discharge of pus or blood.
A Traumatic perforation of the eardrum may occur:
- By a slap on the ear
- As part of a skull fracture
- After a sudden explosion from a bomb blast or fire cracker blast
- Insertion of a pin, cotton bud or stick if pushed too far into the ear canal.
A traumatic perforation usually has irregular shape and size and irregular edges.
Symptoms and Signs of a Ear drum perforation: A perforated eardrum is usually accompanied by decreased hearing, occasional discharge, tinnitus and sometimes vertigo. Pain is usually not present.
Due to loss of drum surface area, less sound vibrations reach the middle ear and internal ear with resulting deafness. It is difficult to determine the location of the source of sound – that is directional (stereophonic) hearing is difficult. Appreciation of stereophonic music is affected.
When old age deafness sets in due to age related changes of the organ and nerves of hearing, the additional hearing impairment in the affected ear would be more pronounced than in the better hearing ear and becomes a definite handicap in communication.
Usually, the larger the perforation, the greater the loss of hearing. If disruption of the chain of bones in the middle ear occurs less sound is transmitted to the inner ear, the loss of hearing is more severe. The type of of deafness is of the Conductive type.
If the perforated eardrum is due to a sudden severe trauma (e.g. skull fracture) traumatic or explosive event like a cracker or bomb blast, because of shake up of the ultra microscopic hair cells in the inner ear, the hearing loss may be very pronounced – a mixed hearing loss from a summation of the conductive component – ear drum perforation and dislocation of the small bones in the middle ear and a sensori neural component due to inner ear damage. from damage to the inner ear structures,
Rarely, a long standing perforation may be the precursor of a cholesteatoma
A perforation of the ear drum creates a system of a tube open at both ends. Water, oil or even ear drops instilled into the ear can flow freely from the external ear into the middle ear and into the back of the nose and throat by the eustachian tube. Conversely, nasal discharge can flow freely from the back of the nose via the eustachian tube into the middle ear and come out through the perforation into the external ear.
As long as the perforation remains, there is therefore, a chance of getting recurrent ear discharge. This can happen every time after catching a cold since blowing the nose forces nasal discharge into the middle ear. It also happens if water accidentally enters the ear as during a bath or during swimming when the infected water comes into contact with the delicate lining of the middle ear and excites an inflammation (otitis media) with resulting ear discharge.
Tinnitus (Noise in th Ear)
A continuous or intermittent noise in the ear can be present. This usually disappears after closure of the perforation by surgery.
Continuous or intermittent episodes of vertigo may occur, since the organ of hearing and balance are one anatomically connected organ.
Natural course of a Ear drum perforation
Eardrum perforations of small size may heal spontaneously in a few weeks.
Medium sized perforations may or may not heal on their own.
Large perforations cannot heal on their own and require surgery.
Pure tone audiometry
Acoustic Impedance Bridge
X-Ray mastoid bone for central perforation & C.T. Scan temporal bone for chronic mastoiditis
Treatment of a Perforated Eardrum
The benefits of closing a perforation include prevention of recurrent middle ear infection by preventing water entering the middle ear while showering, bathing, or swimming (which could cause ear infection), improved hearing, and diminished tinnitus. It also may prevent the development of cholesteatoma (skin cyst in the middle ear), which can cause chronic infection and destruction of ear structures.
A small perforation can be kept under observation to see if it could close spontaneously. or try to cauterize the edges of the perforation under the operating microscope, with a chemical to stimulate growth of epithelium from the surrounding area to grow over the perforation. If healing is not achieved, surgery has to be considered.
A large or moderate sized perforation requires a surgical operation (Tympanoplasty or Myringoplasty) to close it. There are a number of surgical techniques, all of which aim at placing a piece of fascia covering the Temporalis muscle across the perforation. Surgery is typically quite successful in closing the perforation permanently, and improving hearing.
By a small incision within the ear canal, the ear drum perforation edges are freshened. The ear drum has 3 layers. These layers are gently separated under an operating microscope. A tissue graft (temporalis fascia) is obtained by a small separate incision above the ear (requiring one stitch). This is placed carefully in between the ear drum layers. The operation is performed under local anaesthesia with sedation. Hospitalization is for a few hours.
Precautions to prevent recurrent ear discharge in patients with chronic ear infection
- Water or oil should not enter the ear at all. Before a bath, the ear canal is sealed with a cotton ball smeared with vaseline or any other hair dressing. Wash hair with head hanging down under a running tap. Dry well with a towel before standing up again.
- Swimming is NOT advisable at all, till the perforation has been closed by surgery. If you have to swim, do so without dipping the head under water. No diving at all.
- Do NOT allow your ear to be syringed by your doctor at all.
- Do NOT use towel corners, match sticks, hair grips to clear the ear. They provoke infection
- Do not blow the nose when you have a head ‘cold’. This will drive the nasal discharge into the middle ear via the Eustachian tube and start a ear discharge. To clear nasal discharge, sniff in and throw out the discharge through the mouth. If you sneeze, do so with mouth open.
- If there is any itching in the ears or you feel the need to clean the ear, do so with cotton buds only after smearing an antibiotic-antifungal cream like Surfaz SN cream
- Every time you catch a ‘cold’, there is a likelihood of recurrence of ear discharge. Hence avoid iced water, ice creams, cold drinks etc. Avoid undue exposure to cold.
- On catching a cold, immediate treatment from the family physician is started.