Tubotympanic Chronic Suppurative Otitis Media

Tubotympanic Chronic Suppurative Otits Media

Tubotympanic Chronic Suppurative Otitis Media

Aetiology of Tubotympanic CSOM

1. Sequela of Acute Otits Media following exanthematous (eruptive) fever and leaving behind a large central perforation which becomes permanent and permits repeated infections from external ear.
2. Ascending infections via Eustachian tube like from tonsils, adenoids and infected sinuses.
3. Persistent mucoid otorrhoea is sometimes result of allergy to ingestants such as milk,eggs,fish etc.

Pathology of Tubotympanic CSOM

Pathology of Tubotympanic CSOM

1. Perforation of pars tensa- Central perforation
2. Middle ear mucosa- Normal when disease is inactive but oedematous and velvety when active
3. Polyp- Pale
4. Ossicular chain- usually intact and mobile but may show some degree of necrosis, especially of long process of incus.
5. Tympanosclerosis- It is hyalinisation and subsequent calcification of subepithelial connective tissue. It is seen as white chalky deposits on promontory, ossicles, joints, tendons, oval and round windows. It interferes with mobility of these structures, hence, causing conductive deafness.
6. Fibrosis and adhesion- They are result of healing process and may further impair mobility of ossicular chain or block eustachian tube.

Bacteriology

1. Aerobic
2. Pseudomonas aeruginosa, proteus, E.coli, Staph aureus
3. Anaerobic
4. Bacteriodes fragilis and anaerobic streptococci

Clinical features of Tubotympanic CSOM

1. Ear discharge- Non-offensive, mucoid or mucopurulent, constant or intermittent. Discharge appears mostly at time of upper respiratory tract infection or accidental entry of water into ear.
2. Hearing loss- Conductive type and rarely exceeds 50dB. Sometimes, patient reports of paradoxical effect, i.e, hears better in presence of discharge than when ear is dry. This is due to 'round window shielding effect' produced by discharge which helps to maintain phase differential. In dry ear with perforation, sound waves strike both oval and round windows simultaneously, thus, cancelling each others effect.
3. Perforation- Always central which is anterior,posterior or inferior to handle of malleus or subtotal/extending upto annulus.
4. Middle ear mucosa- Pale pink and moist on normal but when inflamed, it looks red, oedematous and swollen and occasionally with polyps.

Shielding effect in CSOM

Perforation in CSOM

Investigations of Tubotympanic CSOM

1. Examination under microscope- can reveal granulation, ingrowth of squamous epithelium, status of ossicular chain, tympanosclerosis and adhesion.
2. Audiogram- Conductive deafness but sensorineural deafness element may be present.
3. Culture and sensitivity of ear discharges- may help to select proper antibiotic ear drugs.
4. Mastoid Xrays/CT scan temporal bone- Mastoid is usually sclerotic but may be pneumatized with clouding of air cells. There's no evidence of bone destruction (which is a feature of atticoantral csom)

Treatment of Tubotympanic CSOM

1. Aural toilet- All discharge and debris from is ear is removed to enhance effect of topical antibiotics.
2. Ear drops- Neomycin, Polymysin and gentamycin are used.
3. Systemic antibiotics- Only in acute cases.
4. Precautions- Avoiding hair washing, water in ears or blowing nose hard can be helpful.
5. Surgical treatment- Polyps in ear or granulation is removed to facilitate ear toilet though avulsion is strictly avoided.
6. Treatment of contributory causes- Corrects of infection of adenoids, maxillary antra and nasal allergy.
7. Reconstructive surgery- Once ear is dry, myringoplasty with/without ossicular reconstruction and closure of perforation can stop recurrent infections.

Labels: ENT, Third year MBBS