• CSOM can be classified according to the degree of involvement of the structures of the middle ear 
  • It involves the anterior inferior part of middle ear cleft (eustachian tube and mesotympanum).
  • Tubotympanic type is also called safe or benign type as there is no risk of serious complicatiions.
  • Residue of an Acute Otits Media during childhood.
  • Acute necrotizing Otits Media
  • Repeated infections from the Eustachian Tube
  • Large sized traumatic perforation.
Involvement of disease
  • Perforation-usually in the form of central perforation situated exclusively in the pars tensa.
  • In long standing disease,erosion of ossicles,particularly of long process of Incus may occur.
  • Polyp or granulations may be seen if few cases.
  • Cholesteatoma is not seen.
Clinical features:
  • Discharge:Mucoid,copius and non-foul smelling.It becomes profus during an upper respiratory tract infection.
  • Deafness-is conductive in type.Degree varies with the position and size of perforation and involvement of ossicles.
  • Round window shielding effect — patient hears better in the presence of discharge than when the ear is dry.
  • Conservative management is the treatment of choice.
  • Aural toilet,Antibiotic Ear drops,treatment of focii of infection like tonsilitis,sinusitis.
  • Removal of polyp or granulation tissue-if present in the middle ear.
  • Myringoplasty in case of persistent perforation,Tympanoplast-in case of persistent perforation with ossicular involvement.
  • It involves postero-superior part of middle ear cleft (attic, antrum and mastoid).
  • Risk of intracranial extension of infection, and thus the risk of complication, is very high, therefore it is called dangerous or unsafe ear.
  • It is associated with Cholesteatoma.
  • Cholesteatoma is a sac lined by keratinizing stratified squamous epithelium in the middle ear cleft .
Cause of Cholesteatoma:
  • Congenital
  • Acquired:
  1. Primary:Retaction pockets.
  2. Secondary:Migration,Metaplasia
Clinical Features:
  • Ear Discharge-scanty,foul smelling,painless and sometimes blood stained.
  • Deafness-It is of conductive type but if complications like labyrinthitis intervene, SNHL may also be seen.
  • Otalgia is not seen in case of cholesteatoma.
  • Complications;may cause symptoms of headache,vertigo,facial palsy or ear ache.
Involvement of disease
  • Perforation is situated either in pars flaccida or marginally in the posterior superior quadrant of the pars tensa.
  • Perforation of tympanic membrane with destruction of tympanic annulus is called Marginal perforation.
  • Cholesteatoma is visible with the perforation and the greyish white or pearly sheets of keratin are easily recognised.
  • Polyps and Granulations may be seen.
  • Ossicles may be affected.
  • Surgery is the treatment of Choice.
  • Tympanomastoid exploration is required which may be Atticotomy,Modified radical mastoidectomy or Radical Mastoidectomy in rare cases or combined approach tympanoplasty Modified Radical Mastoidectomy is the treatment of choice.
  • In case of symptoms suggestive of complications like Vertigo,Facial palsy,Immediate Mastoid exploration is required.
  • Pus culture in CSOM may show multiple organisms.
  • Most commonly isolated organisms are gram negative bacilli, i.e., Pseudomonas, proteus, E.coli.
  • These organisms are not commonly found in the respiratory tract, while commonly found in the skin of external ear.
Exam Question
  • Most common organism cultured in CSOM is Pseudomonas seruginosa.
  • Treatment of choice in a patient of CSOM has choleastatoma and presenting with vertigo or Facial Palsy is immediate Mastoid Exploration.
  • Perforation of pars flaccida is associated with cholesteatoma.
  • Perforation of tympanic membrane with destruction of tympanic annulus is called Marginal perforation.
  • Treatment of choice for Perforation in pars flaccida of the tympanic membrane with cholesteatoma is Modified Radical Mastoidectomy.
  • Cholesteotoma is seen in Attico-antral CSOM.
  • Ossicle M/C involved in CSOM is Long process of Incus.
  • CSOM is caused by multiple bacteria.
  • Conservative management is the treatment of choice in central,safe tympanic membrane perforation.
  • Treatment of choice in case of Attico-antral Cholesteatoma is Modified radical Mastoidectomy/Tympano-mastoid exploration.
  • Cholesteatoma is associated with scanty,foul smelling,painless discharge.
  • 7 th cranial nerve is most commonly involved in CSOM.
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