1. BY
Dr.K.AMRITHAANILKUMAR
PRESENTS

3. Kural 411
செல்வத்துட் செல்வஞ் செவிச்செல்வம் அச்செல்வம்
செல்வத்து செல்லாந் தலல.
TRANSLATION
Wealth of wealth is wealth acquired be ear attent;
Wealth mid all wealth supremely excellent.
EXPLANATION :
Wealth (gained) by the ear is wealth of
wealth; that wealth is
the chief of all wealth.

4. MIDDLE EAR

5. 2.Middle ear
Includes ,
• Eustachian tube
• Tympanic cavity
• Aditus
• Mastoid air cells

6. Eustachian tube
• It is 36 mm long in adults
• Enters nasopharynx 1.25 cm
behind posterior end of inferior
turbinate
• Lateral 1/3- bony
• Medial 2/3 – fibrocartilaginous
• Junction - isthumus , narrowest
part of ET

8. Anatomy of cartilagenous
part
• It lies posteromedially
• Consists of medial and lateral
lamina seperated by a elastic
hinge
• Anterolaterally – ostmanns fat pad

11. Blood supply
• Ascending pharyngeal artery
• Middle meningeal artery
• Artery of pterygoid canal
• Veins – pterygoid venous
plexuses

13. Tympanic cavity
Includes
• Epi tympanium
• Meso tympanium
• Hypo tympanium

14. Walls of Tympanic cavity

15. • Roof
• Thin plate of bone called tegmen
tympani , separates he tympanic cavity
from middle cranial fossa
• Extends posteriorly to form roof of the
aditus and antrum
• Floor
• Thin plate of bone separates tympanic
cavity from the jugular bulb
• Medial border – tympanic branch of the
glossopharyngeal nerve ( IX) enters
middle ear

17. • Anterior wall
• Thin plate of bone separates the
cavity from internal carotid artery
• Lateral wall
• Membranous - tympanic membrane
• Bony - lateral attic wall
above pars flaccida
Lateral wall of hypo
tympanum

18. Lateral wall

19. Medial wall
It has
• Promontory
• Oval window
• Round window
• Tympanic part of bony facial nerve
canal
• Lateral semicircular canal
• Processes cochleaformis

21. • Promontory
• is a round elevation occupying much of
central portion of medial wall
• formed by basal turn of cochlea
• usually as small grooves on its surface
containing the nerves which form the
tympanic plexuses

23. Oval window
• Lies behind & above he promontory
• A kidney shaped opening that connects
the tympanic cavity with the vestibule
• Close by footplate of stapes
• Size – 3.25mm long & 1.75 mm wide

25. Round window
• 2.3 X 1.9 , placed right angle to the
foot plate of stapes
• Lies below & behind the oval window
• Separate by subiculum ( post extension
of promontory)
• Ponticulus – another ridge above
subiculum & runs to pyramid on
posterior wall
• Sinus tympani – where the ponticulus
& subiculum meet

26. Facial nerve canal
• Facial nerve canal ( fallopian canal ) runs above
the promontory and oval window in an
anteroposterior direction
• Anterior – processus cochlariformis , a curved
projection of bone it anteriorly houses the tendon
of tensor tympani muscle & laterally to the handle
of malleus
• Above – forms the medial wall of epi tympanum
• Behind --facial canal starts to turn inferiorly as it
begins to descent the posterior wall of tympanic
cavity
• Posterio lateral - The dome of lateral semicircular
canal (posterior portion of epitympanium),

30. posterior wall
• Aditus & antrum
• Fossa incudes for short process of incus
• Bulge produced by lateral semicircular
canal
• Pyramidal eminence for stapedius tendon
• Bulge produced by vertical part of facial
nerve
• Sinus tympani
• Facial recess

32. Posterior wall
• Upper part – large irregular opening – the
aditus and antrum that leads back from the
posterior epitympanium into mastoid
antrum
below
Small depression , fossa incudis ,houses the
short process of incus & suspensory ligament
below
Opening in chorda tympani nerve is Pyramid,
a small hollow conical projection with its
apex pointing anteriorly

33. facial recess
• Is a groove which lies between
pyramid with facial nerve & annulus
of tympanic membrane
• Bounded by
• Medially – facial nerve
• Laterally – tympanic annulus
• Obliquely – chorda tympani nerve
running between 2

35. sinus tympani
• Bounded by
• Superior – ponticulus
• Inferior - subiculum
• Lateral - mastoid segment of facial
nerve
• Medial - posterior semicircular
canal
• Site for – cholesteatoma recurrence

37. contents of middle ear
cavity• Air
• 3 ossicles – malleus, incus, & stapes
• 2 muscles – tensor tympani &
stapedius
• 2 nerves - chondral tympani &
tympanic plexus
• Mucosal folds & ligaments
• Blood vessels

39. Muscles of middle ear

41. Chorda tympani nerve
• Enters tympanic cavity from posterior
canaliculus at the junction of lateral and
posterior wall
• Runs across medial surface of Tympanic
membrane btn mucosal & fibrous layers
• Passes medial to upper portion of the handle
of malleus
• Leaves through petro tympanic fissure
• Carries taste sensation from anterior 2/3 from
same side of tongue & secretomotor fibres to
submandibular gland

43. Tympanic plexus
• Formed by
• Tympanic branch of glossopharyngeal
nerve ( jacobsons nerve )
• Caroticotmpanic nerves , arise from
sympathetic plexus around internal
carotid artery

45. • Nerves form plexuses on promontory &
provide branches to mucous membrane
lining the tympanic cavity , Eustachian
tube, mastoid antrum & air cells
• Plexus provide branches to join the
greater superficial petrosal nerve &
lesser superficial petrosal nerve
contains all the parasympathetic fibres
of the glossopharyngeal nerve.

46. Mastoid air cells
• Interconnected & lined by squamous
non – ciliated epithelium
• Mastoid process can be pneumatic ,
sclerosed or mixed
• Mastoid process develops by age of 2
yrs
• Adius & antrum is the opening in
posterior wall of middle ear & leads
posteriorly to antrum

48. Mastoid antrum
• The roof of mastoid antrum ( tegmen
antri ) separate it from middle cranial
fossa
• Lateral - squamous temporal bone
• Medial – posterior & horizontal
semicircular canal
• Posterior – communicate by several
openings with mastoid air cells
• Specific site –MacEwen’s triangle

49. Macewens triangle
• superior – temporal line
• anterior – posterior – superior margin
of bony external auditory canal
opening
• posterior – tangent drawn to mid –
point of posterior wall of external
auditory canal
• contain spine of henle
• mastoid antrum lies 12 – 15 mm deep
to triangle

51. mucosa of middle ear cleft
• mucus membrane of the nasopharynx is
continuous with that of middle ear,
aditus , & antrum
• mucus secreting
• respiratory type
• cilia bearing
• lines the bony wall of tympanic cavity &
wraps the middle ear structure –
ossicles , mucosal ligaments ,& nerves
like peritoneum wraps viscera of the
abdomen

52. Blood supply
• arteries
• 2 main – anterior tympanic branch of
maxillary artery
Stylomastoid branch of posterior
auricular artery
• 4 minor – petrosal branch of middle
meningeal artery
Superior tympanic branch of
middle meningeal artery
Branch of artery of pterygoid canal
Tympanic branch of internal carotid
• Veins – pterygoid venous plexuses
Superior petrosal sinus

54. Lymphatic drainage
Area Nodes
• Concha, tragus, fossa
triangularis & external
cartilaginous canal
• lobule and antitragus
• Helix & antihelix
• Middle ear & Eustachian tube
• Inner ear
• Preauricular & parotid nodes
• Infra auricular nodes
• Post auricular nodes, deep
jugular & spinal accessory
nodes
• Retro pharyngeal nodes –
upper jugular chain
• No lymphatics

56. CLINICAL ANATOMY OF MIDDLE
EAR
1. Acute suppurative otitis media
- It is an acute
Inflammation of
Middle ear by pyogenic
Organisms
- Middle ear includes
1. Eustachian tube
2. Middle ear
3. Attic
4. Aditus
5. Antrum & Mastoid
air cells

57. 2. Otitis media with effusion
Syn.- Serous otitis media,secretory
otitis media ,Glue Ear
It is an insidious cndn Characterised by
Accumulation of non-purulent effusion
In the middle ear cleft Effusion is thick & viscid

58. 3. Cholesteatoma
“Skin in wrong Place”
- Middle ear is lined
either by
ciliated columnar
or cuboidal cells.
- But whereas
in cholesteatoma,
it is lined by
Keratinizing Squamous epithelium

59. 4. Chronic suppurative
otitis media
It is a long standing infection of a part or
whole of middle ear cleft Characterized
by ear discharge & permanent
perforation.

60. REFERENCES
• Diseases of Ear, Nose and Throat & Head
and Neck Surgery by P L Dhingra
• BD Chaurasia's Human Anatomy Regional
and Applied Dissection and Clinical: Vol. 3:
Head-Neck Brain

61. A
Special
Thank you
To
A
Very
Special Doctor
en love da Homoeopathy