Diseases of the Middle Ear Lecture Notes PDF

Diseases of the middle ear Dr. Naslshah Kazem Diseases of the middle ear ▪ CONGENITAL ANOMALIES ▪ TRAUMA OF THE MIDDLE EAR INFLAMMATIONS OF THE MIDDLE EAR  CONGENITAL ANOMALIES ▪ -Dehiscence of the bony facial canal (horizontal part) ▪ predisposes to facial paralysis during attacks of...

Diseases of the middle ear Dr. Naslshah Kazem Diseases of the middle ear ▪ CONGENITAL ANOMALIES ▪ TRAUMA OF THE MIDDLE EAR INFLAMMATIONS OF THE MIDDLE EAR  CONGENITAL ANOMALIES ▪ -Dehiscence of the bony facial canal (horizontal part) ▪ predisposes to facial paralysis during attacks of: ▪ acute otitis media ▪ cholesteatoma ▪ ear surgical trauma. ▪ Fixation or absence of ossicles causing conductive deafness. ▪ Dehiscence of the floor of the tympanic cavity ▪ predisposes to injury of the jugular bulb during tympanoplasty leading to severe hemorrhage. TRAUMA OF THE MIDDLE EAR Traumatic rupture of the drum: Causes: -Indirect trauma: Slap, blast or otitic barotrauma. -F.B. or during its removal, clumsy ear wash, fracture base of the skull. Symptoms: -Slight pain. -Mild deafness and tinnitus. -Minimal bleeding. INFLAMMATIONS OF THE MIDDLE EAR ▪Acute otitis media ▪Chronic suppurative otitis media (c.S.O.M) ▪ Cholesteatoma ▪ Non-suppurative otitis media ▪ Otosclerosis ACUTE OTITIS MEDIA An acute inflammation of the mucoperiosteal lining of the middle ear cleft. ▪ Causative organisms: -Bacterial as Haemophilus influenza, streptococci and staphylococci. -Viral as influenza. ▪ Routes of infection: Through the Eustachian tube: In diseases of: -Acute rhinitis, acute sinusitis, acute pharyngitis. -Acute tonsillitis and adenoiditis, common cold. -Milk regurge during suckling in infants. Through drum perforation: During swimming and bathing ACUTE OTITIS MEDIA Clinical picture: A) Before perforation: ▪ - Fever which is higher in children, throbbing pain, deafness and tinnitus. ▪ - On examination: bulging of the drum, conductive deafness. B) After perforation: ▪ - Necrosis of the drum anywhere causes perforation. ▪ - Discharge, deafness, fever and pain diminish. ▪ - On examination: Perforated drum, mucopurulent or purulent discharge and conductive deafness. ACUTE OTITIS MEDIA ▪Treatment -Antibiotics, analgesics and nasal decongestive drops. -Myringotomy to allow drainage before perforation. ▪Complications of acute otitis media -Cranial: Mastoiditis, facial paralysis. -Intracranial: rare SEQUELAE OF ACUTE OTITIS MEDIA Healing: arrest of discharge, normal drum and normal hearing. -Non-resolution: is due to inadequate treatment, virulent organisms and low resistance of the patient. This may manifest by: A) Residual deafness due to: -Secretory otitis media: Fluid collects in the middle ear due to Eustachian tube obstruction or mild infection. Treated with myringotomy and ventilation tube (Grommet's tube). -Residual perforation: treated with myringoplasty. B) Residual discharge due to: -Persistence of the cause: treated with tonsillectomy and adenoidectomy. -Masked mastoiditis: treated with cortical mastoidectomy.  ACUTE OTITIS MEDIA IN INFANTS ▪ Otitis media is more common in infants than in adults ▪ Why? children are more susceptible to infection than adults due to their low resistance as a result of teething, gastrointestinal troubles and artificial feeding. a) Adenotonsillitis and recurrent upper respiratory tract infections. b) Milk regurge during suckling enters the Eustachian tube when the child suckles in the supine position. c) The Eustachian tube is shorter, more horizontal and wider than in adults.  ACUTE OTITIS MEDIA IN INFANTS Clinical picture: Treatment : Symptoms: Mainly general. Treatment: -Fever, vomiting and diarrhea. - Antibiotics, analgesics and nasal -Child cries, restless, moves his head and decongestive drops. pulls his ears. -Myringotomy under general anesthesia is Signs: done if not resolved. -The drum is congested. Bulging is late as the drum is thicker and more oblique than in adults.  CHRONIC SUPPURATIVE OTITIS MEDIA (C.S.O.M) Chronic infection of the middle ear: Causing conductive deafness and discharge from a perforated drum. Clinical types: 1. Tubotympanic disease: Safe ear 2. Attico-antral (Cholesteatoma): Unsafe ear It is a safe mucosal affection of Eustachian tube and tympanic cavity. It is due to It is unsafe bony affection of the attic, inefficient treatment, inadequate drainage, antrum and bony walls of the low resistance of the patient or high mastoid air cells. virulence of the organism in cases of repeated attacks of acute otitis media.  CHRONIC SUPPURATIVE OTITIS MEDIA (C.S.O.M) Signs Safe ear Unsafe ear 1. Deafness Conductive and not severe Conductive and severe 2. Discharge Mucopurulent Purulent profuse Scanty odorless Foul odor 3. Perforation Central Marginal or attic 4.Cholesteatoma Very uncommon Very common CHRONIC SUPPURATIVE OTITIS MEDIA (C.S.O.M) Clinical picture: Symptoms of C.S.O.M.: 1. Deafness. 2. Discharge. Signs of C.S.O.M.: 1. Perforation 2. Granulations 3. Polypi. 4. Conductive deafness. CHRONIC SUPPURATIVE OTITIS MEDIA (C.S.O.M) Investigations: -X-ray and CT scan of the mastoids. -Culture and sensitivity test for the discharge. -Audiological assessment. Treatment: -Tubotympanic type: (Safe type) Tympanoplasty in done after trials to make the ear dry by conservative treatment using antibiotics, suction, ear drops and removal of the source of infection as tonsils and adenoids. CHOLESTEATOMA: ▪ bag-like ▪ Cystic ▪ foul smelling mass. ▪ It is formed of keratinizing desquamated squamous epithelium, pus, cholesterol crystals and proteolytic enzymes. ▪It erodes bone by chemical (proteolytic enzymes) and bacterial action (secondary infection). ▪The abnormal presence of the squamous epithelium in the middle ear is either congenital or acquired. CHOLESTEATOMA: ▪ WHY? ▪ Theories of cholesteatoma: ▪ a) Congenital cholesteatoma arises from embryonic epithelial rests in of the petrous bone. ▪ It could be arise at cerebellopontine angle (CPA) or middle ear. ▪ In CPA, it may present with facial nerve paralysis, nerve deafness and vertigo while in the middle ear it leads to conductive deafness behind an intact drum.  CHOLESTEATOMA: b) Acquired cholesteatoma may be due to: ▪ Primary acquired cholesteatoma: ▪ Invagination of pars flaccida (attic retraction) in repeated prolonged Eustachian obstruction. ▪ The flaccid part of the drum is sucked and is separated as a sac filled with squamous epithelium in the attic. ▪ Secondary acquired cholesteatoma: -Invasion of middle ear by the skin of the external canal through a marginal perforation (migration). -Metaplasia of the flattened epithelium of the middle ear by infection into stratified squamous epithelium. CHOLESTEATOMA: Clinical picture: Symptoms of C.S.O.M.: 1. Deafness. 2. Discharge. Signs of C.S.O.M.: 1.Perforation 2. Granulations 3. Polypi. 4. Conductive deafness CHOLESTEATOMA: Investigations: -X-ray and CT scan of the mastoids. -Culture and sensitivity test for the discharge. -Audiological assessment. Treatment: -Tubotympanic type: (Safe type) Tympanoplasty in done after trials to make the ear dry by conservative treatment using antibiotics, suction, ear drops and removal of the source of infection as tonsils and adenoids.  CHOLESTEATOMA: Treatment -Atticoantral Cholesteatoma: (Unsafe type) a) Atticotomy when it is limited to the attic. b) Modified radical mastoidectomy if it is localized to the attic and antrum. c) Radical mastoidectomy for extensive cholesteatoma or the presence of complications.  NON-SUPPURATIVE OTITIS MEDIA ▪ SECRETORY OTITIS MEDIA (SOM) Accumulation of a non-purulenteffusion in the middle ear cleft. It may be serous or mucus (glue). The disease is common in children. ▪ Commonest cause of conductive (deafness in children) ▪ Middle ear effusion ▪ Otitis media with effusion ▪ Glue ear SECRETORY OTITIS MEDIA (SOM) ▪ WHY? ▪ -Eustachian tube pathology: allergy, inflammation, + Barotrauma adenoids, nasopharyngeal cancer cleft palate. ▪ -Unresolved acute otitis media due to inefficient treatment. SECRETORY OTITIS MEDIA (SOM) Clinical picture: Symptoms: -Deafness and tinnitus. -Bubbling sounds in the ears. a sense of "fullness" or "pressure" in ear Signs: 1. Conductive deafness. 2. Otoscopic examination: The drum is intact, but retracted. A fluid level forms a hair line due to interruption of the fluid by the handle of malleus. SECRETORY OTITIS MEDIA (SOM) Diagnosis: -Tuning fork test: conductive deafness. -Pure tone audiometry: air bone gap. -Impedence audiometry: flat curve with absent stapedial reflex SECRETORY OTITIS MEDIA (SOM)  SECRETORY OTITIS MEDIA (SOM) Medical: ▪ Nasal drops, NOT an inf. don’t give antibiotic ▪ anti-allergic, ▪ steroids ▪ mucus dissolvent. Surgical: ▪ Myringotomy and insertion of ventilation tubes (Grommet's tube). ▪ Surgery of the causative factor e.g. removal of adenoids. OTOSCLEROSIS ▪Heredo-familial disease. ▪Conductive deafness due to fixation of the footplate of the stapes in the oval window. ▪ Formation of new spongy bone of greater thickness, celullarity and vascularity which replaces the normal compact bone of the bony labyrinth. OTOSCLEROSIS ▪ Deafness usually starts between 20 and 30 years of age. ▪Positive family history in more than 50% of the cases. ▪Females (pregnancy) are more commonly (2:1) affected between 20-40 years. ▪Bilateral in most cases. OTOSCLEROSIS Clinical picture: ▪ Symptoms: ▪ Deafness and tinnitus. Deafness increases during pregnancy. ▪ Paracusis: the patient hears better in noisy places as the speaker spontaneously raises his voice. (CHL reduces the volume of the back ground noise). Signs: ▪ Conductive deafness with normal drum and patent Eustachian tube. ▪ Schwartz's sign: flamingo red color of the drum reflecting dilated blood vessels of the promontory indicating active disease (rich vascular supply associated with immature bone). ▪ Cochlear otosclerosis is due to invasion of the cochlea causing SNHL. OTOSCLEROSIS Investigations: Tuning fork test: conductive deafness in stapedial otosclerosis. Rinne’s test: negative Weber test’s: lateralized to worth ear Air bone gap with Carharts notch (at 2000Hz). ▪ Proposed theory ▪ Stapes fixation disrupts the normal ossicular resonance (2000 Hz) ▪ Bone conduction is disturbed because of relative perilymph immobility ▪ Reverses with stapes mobilization - Mixed hearing loss in combined otosclerosis. -SNHL in cochlear otosclerosis. OTOSCLEROSIS ▪ Impedance audiometry: restricted curve (As) with absent stapedial reflex due to fixation of the stapes. OTOSCLEROSIS ▪ TREATMENT ▪ Sodium fluride is ineffective, may be used in active stage of the disease. ▪ Stapedectomy and replacement of the stapes by prothesis (Teflon piston). ▪ Hearing aid is indicated in severe mixed deafness or if the patient refuses the operation.  THANKS & GOOD LUCK