eustachian tube, ENT

1. Eustachian tube dysfunction
and management
- Dr. Sujitha. M ( DNB ENT - 1st year)

2. Introduction
Eustachian tube also known as Auditory tube or pharyngotympanic tube
Development - From tubotympanic recess
Anatomy
36mm long tube
Eustachian tube is divided into two parts
1. Bony part
2. Cartilaginous part

3. Bony Part - 1/3rd 12mm
1. Posterolateral part of ET
2. Opening into the anterior wall of middle ear
3. Passes through the squamous and petrous part of temporal bone
4. Joints with cartilaginous part at isthumus (Narrowest 2mm)

4. Cartilaginous part - 2/3rd 24mm
1. Anteromedial part of ET
2. Starts from isthumus - runs downwards, forwards and medially to the
lateral wall of nasopharynx

5. 1. ET opens 1 to 1.25 cm below and behind the posterior end of inferior
turbinate
2. Cartilage lies directly below the mucous membrane, It forms an
elevation - TORUSTUBARIS
3. Lymphoid enlargement around torustubaris - Tubal tonsils
4. Behind Torustubaris, depression or pouch is called FOSSA OF
ROSENMULLER - Common sight of origin of NP Malignancy

6. ET Lining
1. Mucosa - Pseudostratified ciliated columnar epithelium with mucous
secreting goblet cells
2. Submucosa - Cartilaginous ET - seromucinous glands

7. - OSTMANN'S FATPAD -
Antrolateral surface of cartilaginos
part of ET
- ELASTIN HINGE - Cartilage at
junction of medial and lateral
lamina at the roof
It keeps ET closed and prevents
nasopharyngeal secretion to enter
into ET

9. Nerve supply
Sensory
- Jacobsons nerve (Tympanic branch of
glossopharyngeal nerve IX)
Motor
- Tensor veli palatini - Mandibular branch
of trigeminal nerve V3
- Levator veli palatini and
Salpingopharyngeus - Pharyngeal
plexus - cranial part of XI nerve
through vagus

10. Blood supply
1. Middle meningeal artery
2. Ascending pharyngeal artery
3. Artery of pterygoid canal
- Venous drainage to pharyngeal plexus
- Lymphatics to retropharyngeal lymph
nodes

11. Muscles - openers of ET
1. TVP Tensor Veli Palatini
2. LVP Levator Veli Palatini
3. Salpingopharyngeus
4. Tensor tympani

12. TVP - Tensor Veli Palatini
- Main opener of ET
- Also called dilator tubae
- descends downwards as a single tendon and hooks around pterygoid hammulus
- Origin
1. Spine of sphenoid
2. Scaphoid fossa
3. from the hook of cartilaginous ET ( upper part )

13. LVP Levator Veli Palatini
- Inferior to ET - crosses to medial side and merges with soft palate
- Origin
- lower surface of cartilaginous part of ET
- lower surface of petrous bone

14. Salpingopharyngeus
- weaker muscle
- around the pharyngeal opening of cartilaginous ET and merges with palatopharyngeus

15. EUSTACHIAN TUBE FUNCTION
- Closed during resting state
- Opens during swallowing / yawning / sneezing
- Normal swallowing - 800 times / day ( 1/min in awake , 3/hr in sleep)
Functions
1. VENTILATION OF MIDDLE EAR - maintains middle ear pressure = atmospheric
pressure
2. PROTECTION OF MIDDLE EAR - from nasopharyngeal secretions and loud sounds
3. DRAINAGE- middle ear secretions into nasopharynx

16. TESTS OF TUBAL FUNCTION AND PATENCY
PATENCY
1. POSITIVE PRESSURE - TM BULGE
2. NEGATIVE PRESSURE - TM MOVES INWARDS
TUBAL FUNCTION - Mucociliary clearance

17. POSITIVE PRESSURE - TM BULGE
1. VALSALVA - increase intrathoracic pressure - 33 mmHg - not preferred in tracheostomy
patients
2. FRENZELS TEST - 8 mm Hg
i. Independent of phase of respiration and independent of intrathoracic pressure
ii. preferred in tracheostomy patients
3. POLITZERIZATION

18. 4. EUSTACHIAN TUBE CATHETERISATION - 7 cm
i. Roses ET catheter
ii. Hartmanns ET catheter
- Normal blowing sound - ET patent
- Fluid in middle ear - bubbling sound
- Obstruction to ET - whistling sound
- ET block /incorrect procedure - No sound
Complications
- Injury to ET / scarring / TM perforation / nasal bleed / vasovagal attack
- Difficulty to do in adenoid hypertrophy and nasopharyngeal tumours
Advantages - relieves obstruction and instill medications

19. NEGATIVE PRESSURE - TM MOVES INWARDS
- TOYNBEES TEST - more reliable than valsalva

20. William test

22. TUBAL FUNCTION
- MUCOCILIARY CLEARANCE TEST
- CIiliary dysfunction- for perforated TM to find out ET ciliary action
1. DYE TEST
2. SACCHARINE TEST
3. ANTIBIOTIC / STEROID EAR DROPS
- Sonotubometry - Intact and perforated ™
1. Non invasive / tone delivered through nose and picked from EAC
2. clear sound - ET patent

23. EXAMINATION
1. PNEUMATIC OTOSCOPE - RETRACTED TM ( hallmark of eustachian tube dysfunction
2. ENDOSCOPY - NASOPHARYNGOSCOPE - to look for pharyngeal part of ET +
PHOTOTUBOMETRY / MIDDLE EAR ENDOSCOPE / ET ENDOSCOPE
3. TYMPANOMETRY
i. Normal A curve
ii. Negative pressure - C type
4. IMAGING - MRI / CT / FLUOROSCOPY WITH CONTRAST (for mucociliary clearance)

24. ACUTE EUSTACHIAN TUBE DYSFUNCTION
- URI → ET lining affected infammation + → ETD
- Patient symptoms
- Ear block / ear pain / increased sneeze / cough / URI
- Mild hearing loss +
- O/E - TM dull
- Apply nasal decongestants and valsalva
Treatment
- Nasal decongestant
- Analgesics
- Steam inhalation
- Anti histamines in allergic rhinitis
- Valsalva manoeuvre / blowing balloon.

25. CHRONIC EUSTACHIAN TUBE DYSFUNCTION
- ET lining blocked
- Pressure changes and chemical receptor activation in middle ear causes change in autonomic nervous
system
- Symptoms
- Persistent ear block
- Hearing loss
- Angle of mandible discomfort
O/E - TM - dull / valsalva - no mobility of TM
Investigations
1. Allergy - AEC
2. Hearing - PTA / IMPEDANCE
3. ET function test
4. Tubomanometry
5. Nasal - X ray PNS / CT PNS / DNE / CT TEMPORAL BONE

26. CHRONIC EUSTACHIAN TUBE DYSFUNCTION - Treatment
1. Steroid sprays / antihistamines / nasal drops / leukotriene inhibitors / mast cell stabilisers
2. Valsalva / toynbee manoeuvre
3. Surgery
4. Myringotomy with grommet insertion
5. Laser tuboplasty - KTP laser ( for soft tissue in NP around pharyngeal opening of ET )
6. Balloon dilatation - inflate @ 10 pressure bars for 2 mins under GA - done in adults and children
from 7 years

27. EUSTACHIAN TUBE DYSFUNCTION IN CHILDREN
1. Proper breastfeeding technique
2. Burping

28. EUSTACHIAN TUBE OBSTRUCTION
Mechanical
1. Intrinsic - Allergy/ Inflammation
2. Extrinsic - Adenoids/ Nasopharyngeal
tumours
Functional
1. Collapse - Due to increased cartilage
compliance - Resist tubal opening, poor
tone of TVP muscle

29. Symptoms
1. Otalgia
2. Ear block
3. Hearing loss
4. Tinnitus
Signs
1. Retracted TM
2. OME
3. Congested TM
4. Perforation

30. Disorders of Eustachian tube
Prolonged tubal block leads to locking of ET with
collection of fluids and haemorrhage

31. ADENOIDS
1. Mechanical obstruction of tubal opening
2. Reservoir of pathogenic organisms
3. Allergy - Mast cells of adenoid release,
inflammatory mediators - tubal blockage
4. OME/ recurrent AOM
5. Treatment - Adenoidectomy

32. Cleft palate
1. TVP does not insert into torus tubaris / if
inserts - poor function
2. Torus tubaris abnormalities - high elastin
density - difficult to open ET
3. Recurrent OME
4. Treatment - ventilation of Middle ear with
grommet
Down syndrome
1. Poor tone of TVP and abnormal shape of
nasopharynx causes obstruction of ET
2. OME / Recurrent otitis media

33. Barotrauma
1. Rapid descent / under water diving
2. Failure of ET to maintain middle ear pressure at ambient atmospheric pressure
3. Atmospheric pressure > Middle ear pressure by 90 mm Hg - ET locked
4. Retracted TM + / Conductive hearing loss +
Treatment
1. Antihistamines / nasal decongestants
2. Myringotomy
3. Restore middle ear pressure - catheterisation / politzerisation

34. RETRACTION POCKETS
Any obstruction to the Middle ear ventilation pathway causes retraction pockets or atelectasis of TM
air from ET - mesotympanum - attic / aditus / antrum / mastoid air cells
1. Mesotympanum to attic via anterior and posterior isthmi
2, Middle ear to mastoid air cell through retrofacial air cells
Obstruction of
1. ET - Total atelectasis of TM
2. Middle ear - retraction pocket in posterior part of middle ear
3. Isthmi - attic retraction pocket
4. Aditus - cholesterol granuloma

36. Patulous Eustachian tube - Abnormally patent ET
Severe/ Patulous Less severe/ Semi Patulous
- Decrease in extracellular fluid volume/ Decrease in fat
Causes
1. Wt. loss
2. Disease / old age
3. Oral contraceptive
4. Atrophic rhinitis (small structures)
5. Myasthenia gravis
Complaints
1. ear block
2. autophony of nasal breathing
3. Hearing loss
4. Breathing synchronous
5. tinnitus
O/E - TM moves with respiration - intact Using stethoscope breathing
sound heard

37. - Investigation - Tympanometry
- Tubomanometry
- DD- Minors third labyrinthine window syndrome
- Autophony of voice due to loud bone conduction
- Inv - VEMP / Electrocochleography
Treatment - Reassurance / weight gain / estrogen nasal drops / saturated KI - oral
- Surgery
- Myringotomy with grommet
- Plug surgery
- Injection of implants into ET opening
- Cauterisation of tube
- Subtotal sleeve resection of tubal mucosa
- Inj of calcium hydroxyapatite paste
- Complete occlusion through middle ear

38. THANK YOU