ASOM and Cortical Mastoidectomy specially useful for undergraduate medical students

1. Acute Suppurative Otitis
Media (ASOM)
Dr. Krishna Koirala

2. • Defined as pyogenic infection of middle ear
cleft lasting for < 3 weeks
• Routes for infection
− Via Eustachian tube
− Via Tympanic membrane perforation
− Hematogenous (rare)

3. Predisposing Factors
1. Breast feeding in supine position
2. Recurrent upper respiratory tract infection
3. Nasal allergy
4. Chronic rhinitis & sinusitis
5. Tumours of nose & nasopharynx
6. Cleft palate

4. Bacteriology
1. Haemophilus influenzae
2. Streptococcus pneumoniae
3. Staphylococcus aureus
4. Moraxella catarrhalis
5. Beta hemolytic Streptococci (causative agent in
acute necrotizing otitis media)

5. Stages of ASOM
1. Stage of hyperemia (tubal occlusion)
− Mild earache
− T.M. retracted initially and
congested later
− Blood vessels radiating out from
handle of malleus (cartwheel
appearance)
Cartwheel

6. 2. Stage of Exudation
• High fever, severe earache,
deafness
• Marked congestion and
bulging of T.M.
• Mastoid tenderness
• P.T.A. : high frequency
conductive deafness (due to
mass effect of pus)

7. 3. Stage of Suppuration
– Increased deafness, ear discharge
– Mastoid tenderness +
– Fever and earache decrease
– Otoscopy :
– Bulged, congested tympanic
membrane with a yellow spot
(nipple sign)
– Pulsatile discharge through small
TM perforation (Lighthouse sign)

8. Clouding of mastoid air cells

9. 4. Stage of Coalescent Mastoiditis
• Otorrhea > 2 weeks, otalgia and deafness
• Mastoid reservoir sign : pus immediately fills the EAC
after mopping
• Sagging of Postero-superior bony canal wall due to peri-
osteitis of mastoid floor
• Ironed out appearance of skin over the mastoid due to
thickened periosteum
• Mastoid cavity in X-ray due to hyperemic decalcification

10. 5. Stage of Resolution
• Ear discharge stops
• Hearing improves
• Perforation starts healing up

11. 6. Stage of Complications
• Sub-periosteal abscess
• Vertigo
• Headache + blurred vision + projectile vomiting
• Fever + neck rigidity + irritability
• Drowsiness
• Paralysis of cranial nerve(s)

12. Treatment of ASOM
1. Antibiotic (Co-amoxyclav, Cefuroxime)
2. Nasal decongestants (systemic + topical)
3. H1 anti-histamines
4. Analgesic + anti-pyretic
5. Aural toilet for ear discharge
6. Heat application for severe earache

13. Review after 48 hours
• Earache + fever persists:
− Change to higher antibiotic
− If T.M. is bulging  perform myringotomy and send
ear discharge for C/S
• Earache + fever subside:
− Continue same treatment for 10-14 days

14. Review after 3 months
• No effusion
−No further treatment
• Effusion persists
−Treat as Otitis Media with Effusion (OME)
• Presence of abscess or coalescent mastoiditis
−Cortical mastoidectomy

15. Myringotomy in A.S.O.M.
− Curvilinear incision made in
postero-inferior quadrant
− Incision is curvilinear & not
radial (as in OME), to cut the
fibres of TM (to keep the
opening patent for longer
duration)

16. Why incision in PIQ?
− Less vascular area
− T.M. bulge is maximum
− Ossicles not damaged
− Easily accessible

17. Sub-periosteal abscess &
fistula

18. Pathology
Production of pus under tension  hyperemic
decalcification (halisteresis) + osteoclastic
resorption of bone  breakage of septa and
formation of mastoid cavity  sub-periosteal
abscess  penetration into periosteum + skin 
mastoid fistula formation

19. Sub-periosteal abscess formation

20. Discharging mastoid fistula

21. Mastoid fistula: dry

22. Abscesses related to mastoid
− Post-auricular
− Bezold
− Citelli
− Zygomatic
− Luc
− Retro-mastoid
− Parapharyngeal & Retropharyngeal

23. Abscesses related to mastoid

24. Post-auricular abscess
− Commonest
− Present behind the ear
− Pinna pushed forwards & downwards

25. Bezold’s & Citelli’s abscesses
Bezold: neck swelling
over sternocleido-
mastoid muscle
Citelli: neck swelling
over posterior belly of
digastric muscle

26. Bezold’s abscess

27. − Luc: swelling in external auditory canal
− Zygomatic: swelling antero-superior to pinna +
upper eyelid edema
− Retro-mastoid: swelling over occipital bone
− Parapharyngeal & Retropharyngeal: due to
spread of pus along the Eustachian tube

28. Gradenigo’s Syndrome
Giuseppe Gradenigo (1859 – 1926)

29. Defining Triad
– Persistent otorrhea despite adequate cortical
mastoidectomy
– Retro-orbital pain due to trigeminal nerve
involvement
– Diplopia: convergent squint due to lateral rectus palsy
by injury to Abducent nerve in Dorello’s canal at the
petrous apex

30. • Etiology : Coalescent mastoiditis involving petrous
apex along postero-superior & antero-inferior tracts in
relation to bony labyrinth
• Diagnosis:
– C.T. scan temporal bone for bony details
– MRI to differentiate b/w bone marrow & pus
• Treatment: Modified radical mastoidectomy &
clearance of petrous apex cells

31. Cortical Mastoidectomy

32. Antiseptic dressing

33. Draping

34. Infiltration

35. Marking of incision

36. Wilde’s post-aural incision

37. Incision deepened

38. Musculoperiosteal flap elevated

39. Cortical mastoidectomy begun

40. Exposure of mastoid antrum

41. Widening of aditus

42. Aditus widened

43. Final Cavity

44. Drain put in mastoid cavity

45. Mastoid dressing