Cortical mastoidectomy

3. 1) Coalescent Mastoiditis and Masked
Mastoiditis.
2) CSOMTTD Active Refractory to antibiotics.
3) It is the initial stage of any transmastoid
surgery

4. Approach to:
-Endolymphatic sac surgery.
-Facial nerve decompression.
-Vestibulo cochlear nerve section.
-Translabyrinthine Approach for CP angle.
-Cochlear implant surgery.
-Combined ApproachTympanoplasty.

5. • History:
• Ear discharge
• Hearing loss
• Fever
• Pain
• Facial asymmetry
• Previous surgery
• Medical history

6. • Otomicroscopy:
• Cholesteatomas
• Granulations
• Helps in defining extent of the disease
• Pure tone audiometry:
• Establish hearing loss
• Ear swab
• X- ray mastoid
• CBC
• Coagulation profile

7. • HRCT (0.5mm cuts)
• Pneumatisation
• Ventilation
• Tegmen tympani
• Status of ossicles
• Sigmoid sinus
• Jugular bulb
• Carotid artery
• Facial nerve
• Extent of the disease

9. Anesthesia
 General anesthesia with endotracheal intubation
• Avoid long acting muscle relaxants – facial nerve
monitoring.

10. Position

11. Draping

12. Local Anaesthesia Infilteration
• Lidocaine and adrenaline

13. Incision

14. Incision in children

15. Elevation of Skin Flap

16. Incising Periosteum

17. Elevation of Periosteal Flap

18. Mac Ewen’s Triangle

19. Drilling Along Temporal Line

20. Drilling Posterior to EAC

21. Drill within this triangle and work your
way deeper into the mastoid

22. Identification of LSSC and Dural Plate
 Thesafestwaytofindtheantrumis
tofollowdura
 Itisidentiefiedbychangeincolour
ofthebone(dura seen shining
through thin layer of bone) or
change in the pitch of burr
 Korner's septum is removed and
antrum is entered
 Drilling through the septum will
allow visualization of LCC
 LCC usually appears yellow in
colour in floor of antrum

23. Identification of LSSC and Dural Plate

24. Identification of Incus
 The burr is downsized
and drilling continuous
anteriorly toward the
root of zygoma until
incus seen in fossa
incudis
 Take care not touch the
incus by drill

25. Identification of Sigmoid Sinus
 Exentrate the air cell
around the sigmoid
sinus till the blue color
of the sinus appeared
 Follow the sinodural
plate posteriorly up to
the sinodural angle

26. Identification Facial Nerve
• Landmarks:
• Lateral semicircular
canal – nerve runs
anteroinferiorly
• Short process of
incus – nerve lies
medial at the level of
aditus
• Diagastric ridge –
nerve leaves mastoid
at the anterior end

27. Identification Facial Nerve
• Always drill parallel to the course of facial nerve
• Use ample irrigation to prevent thermal damage
to the nerve

28. Drain is placed and wound closed
• Mastoid cavity is
thoroughly irrigated
with saline to remove
bone dust
• Small rubber drain
placed in the lower
end of incision
• Skin closed

29. Drilling Tips
 Hold the drill firmly but don’t press hard on the
bone
• Avoid keyhole surgery; work through a wide space
• The tip of the drill should always be visible
• Use the ‘equator’ of the burr rather than the tip
• Never drill behind edges of bone
• Drilling should always be parallel to structures that
are to be saved with a lots of water for irrigation
• If the burr is to be lengthened, switch to a diamond
burr

30. Final cavity

33. Extended Cortical Mastoidectomy
 INDICATED For mucosal disease without
cholesteatoma, to avoid canal wall down
mastoidectomy
• Extend drilling anteriorly from antrum to the
aditus and short process of incus
• Drill in the narrow space between roof of EAC
and bone over middle fossa dura.
• Drill forwards to reach the root of zygoma
• Open the entire attic and see the head of
malleus and Incus

34. Widening of aditus

35. Posterior Tympanotomy
 Drilling away of the bone between the
pyramidal (mastoid) segment of the facial
nerve, and the posterior bony canal and
chorda tympani resulting in access to the
middle ear from the mastoid.

36. Indications
• To gain access to mesotympanum via cortical
mastoid cavity
• Cochlear implantation
• Part of combined approach tympanoplasty
• Cholesteatoma in mastoid bowl, and
mesotympanum

38. Posterior Tympanotomy

39. Postoperative Care
• Drain left for 24-48 hours
• Mastoid pressure dressing for 1 day
postoperatively
• Keep the ear dry
• Bacitracin is applied to the postauricular incision
twice a day for 1 week.
• Stitches removed after 1 week
• Postoperative PTA is done after 4 weeks
• Further follow up is after 6 months and then after
1 year

40. Complications
• Persistent deafness:
• Incus dislocation or removal
• Sensorineural hearing loss
• Facial nerve injury
• Persistent infection due to residual cells
• CSF leak – dura may be inadvertently opened
• Vertigo
• Inadvertent entry into the EAC
• Hemorrhage from injury to sigmoid sinus
• Postoperative wound infection .

41. Instructions to the Patient
• For first 3 weeks : gentle activity e.g., housework,
walking only
• After 3 weeks: gentle exercise
• After 4 weeks: normal gym activity
Keep operation site dry