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Acute MastoiditisKeerthivasan
Mastoiditis
The term mastoiditis is used when infection spreads from the mucosa, lining the mastoid air cells, to involve bony walls of the mastoid air cell system.
Aetiology
• Usually accompanies suppurative ottitis media• Determining factors– High virulence of organism– Lowered resistance of the patient
• Children are affected more• Beta hemolytic streptococcus is the most common
cause
Pathology
• Two main pathological processes are responsible– Production of pus under tension – Hyperemic decalcification and osteoclastic
resorption of bony walls
Pathology (cont)
• Inflammation of mucoperiosteal lining air cell system increasing the pus production
• The large amount of pus caanot be drained efficiently through small perforation of tympanic membrane or eusthacian tube
• Swollen mucosa of the antrum and attic also impede the drainage system resulting in accumulation of pus under tension
Pathology (cont)
• Hyperemia and engorgement of mucosa causes dissolution of calcium from bony walls of the mastoid air cells
• Both of these processes combine to cause destruction and coalescence of mastoid air cells, converting them into
• Pus may break through mastoid cortex leading to sub-periosteal abscess which may burst into discharging fistula
Clinical features
• Symptoms – Pain behind the ear• Persistence of pain, increase in intensity or
recurrence of pain after treatment of acute otitis media are significant pointers
– Fever• Persistence and recurrence of fever in a case of
acute otitis media in spite of adequate antibiotic treatment
Symptoms
– Ear discharge• Discharge becomes profuse and increases in
purulence• Discharge may cease due to obstruction • Any persistence of discharge beyond 3 weeks
Signs
• Mastoid tenderness– Tenderness is elicited over the middle of mastoid
process, at its tip, posterior border or root of zygoma.
• Ear discharge– Mucopurulent or purulent discharge, often
pulsatile, may seen coming through central perforation of pars tensa
Signs (cont)
• Sagging of posterior meatal wall– Due periosteitis of bony part of wall between
antrum and deeper posteriosuperior part of bony canal
• Perforation of tympanic membrane– Usually a small perforation seen in pars tensa with
congestion of the rest of tympanic membrane or sometimes may appear as a nipple like protrusion
Signs (cont)
• Swelling over the mastoid– Initially there is edema of periosteum giving an
ironed out feeling to the mastoid– Later retroauricular sulcus becomes obliterated
and pinna is pushed forward and downward– When the pus bursts through bony cortex a
periosteal fluctuant abscess is formed
Signs (cont)
• Hearing loss– Conductive type
• General findings– Patient appears ill and toxic with low grade fever – In children the fever is high with a rise in pulse
rate
Investigations
• Blood count– Polymorphonuclear leucocytosis
• ESR- raised• X-ray mastoid– There is clouding of the air cells due to collection
of exudate in them– Bony partitions between the cells become
indistinct– In later stages a cavity may be seen in the mastoid
Differential diagnosis
• Suppuration of mastoid lymph nodes• Furunculosis of meatus• Infected sebaceous cyst
Treatment
• Hospitalization of the patient• Antibiotics– Start with amoxicillin or ampicillin– Specific antimicrobial is started on receipt of
sensitivity report– Usually chloramphenicol or metronidazole is
added
Treatment (cont)
• Myringotomy– When pus is under tension it is relieved by wide
myringotomy
Treatment (cont)
• Cortical mastoidectomy– Indication• Subperiosteal absc• Sagging of posteriosuperior
meatal wall• Positive reservoir sign• No change in condition of the
patient or it worsens inspite of acute medical tresatment for 48 hours• Mastoiditis leading to
complications
Treatment (cont)
– The aim of mastoidectomy is to externate all the mastoid air cells and remove any pockets of pus. Adequate antibiotic treatment must be continued atleast for 5 days following mastoidectomy
Complications of acute mastoiditis
• Subperiosteal abscess• Labrinthytis• Facial paralysis• Petrositis• Extradural abcess• Meningitis• Brain abscess• Laterla sinus thrombophlebitis• Otitic hyrocephalus
Abscess in relation to mastoid infection
• Postauricular abscess– Commones abscess formed over the mastoid– Pinna is displaced forwards outwards and downwards– Pus travels along vascular channels of lamina cribosa
• Zygomatic abscess– Occurs due to infection of zygomatic air cells situated at
the posterior part of zygoma– Swellings appear in front and above the pinna, edema of
upper eye lid– Pus collects either superficial or deep to temporalis muscle
• Bezold abscess– It can occur following acute coalescent mastoiditis– Presents as a swelling in the upper part of neck– The abscess may • Lie deep to sternocledomastoid• Follow the posterior belly of digastric and present as
swelling between tip of mastoid and angle of jaw• Present in upper part of posterior triangle• Reach the parapharyngeal space• Track down along the carotid vessels
• Meatal abscess (Luc’s abscess)– Pus breaks through bony wall and external osseus
meatus– Swelling is seen in deep part of bony meatus– Abscess may burst into meatus
• Behind the mastoid (Citelli’s abscess)– Formed behind the mastoid more towards the
occipital bone
• Parapharyngeal or retro pharyngeal abscess– This results from infection of peritubal cells due to
acute coalescent mastoiditis
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