Pharynx & Palate

1. Pharynx & Palate
Dr. Prabhakar Yadav
Associatet Professor
Department of Human Anatomy
B.P. Koirala Institute of Health Sciences

3. Pharynx: Fibromuscular tube,
Extent: Base of skull to esophagus,
Location: behind nose, mouth & larynx.
Dimension:
Length: 12–14 cm,
Width: 3.5 cm at its base
1.5 cm at pharyngoesophageal junction

4. BOUNDARIES:
Superior: Base of skull including posterior part of body of sphenoid &basilar part of occipital bone in front of
pharyngeal tubercle
Inferior: Continuous with the esophagus at lower border of cricoid cartilage anteriorly & lower border of C6
vertebra posteriorly

5. Anteriorly: It communicates with the nasal cavity, the oral cavity and the larynx.
Posteriorly: glides freely on prevertebral fascia which separates it from the cervical spine

6. On each side:
• Pharynx is attached to: medial pterygoid plate
• Communicates with middle ear cavity through auditory tube
• Related to: styloid process and muscles attached to it.
• common carotid, internal carotid & external carotid arteries & cranial nerves related to them.

7. NASOPHARYNX
lies behind nasal cavities & above the soft palate.
Boundaries
Roof: -Body of sphenoid.
-Basilar part of occipital bone.
Floor:
- Soft palate (posterior surface).
- Pharyngeal isthmus: opening in the floor between the free edges of soft palate & posterior pharyngeal wall

8. Anterior wall: Formed by posterior nasal apertures.
Posterior wall: sloping surface with roof; supported by anterior arch of C1
Lateral wall: Medial pterygoid plate of sphenoid.

9. Nasopharyngeal (pharyngeal) tonsil: Collection of lymphoid tissue beneath the mucosa at the junction of roof
& posterior wall of nasopharynx.
Orifice of the pharyngotympanic tube (auditory tube/ eustachian tube): Lies on the lateral wall at the level of
inferior nasal concha, 1.25 cm behind it.
Tubal tonsil: Tubal elevation produced by the collection of lymphoid tissue at the upper & posterior margins of
opening of auditory tube

10. (i) Salpingopharyngeal fold: Mucosal fold that extends vertically downwards from tubal elvation & fades on
the side wall of the pharynx.
- It contains salpingopharyngeus muscle.
(ii) Salpingopalatine fold: Mucosal fold that extends downwards & forwards from tubal elvation to the soft
palate.
-It contains levator palati muscle.
Pharyngeal recess (fossa of Rosenmüller): Depression behind tubal elevation;

11. Adenoids: Nasopharyngeal tonsils when enlarge due to infection are known as adenoids
Infection from pharynx can easily pass into middle ear through pharyngotympanic tube.

12. Passavant's Ridge:
Some of the upper fibres of the palatopharyngeus pass circularly deep to the mucosa of the pharynx, and form
a sphincter internal to superior constrictor.
These fibres constitute Passavant's muscle which on contraction raises a ridge called Passavant's ridge on
posterior wall of the nasopharynx.
When the soft palate is elevated it comes in contact with this ridge, closing the pharyngeal isthmus between
the nasopharynx & oropharynx

13. OROPHARYNX
Extent: Lower surface of soft palate to
Upper border of epiglottis
Location: behind the oral cavity
Boundaries
Roof (Above):
Soft palate (anterior surface).
Pharyngeal isthmus
Anterior wall (infront):
(a) Oropharyngeal isthmus
(b) Pharyngeal part of the tongue.
Posterior wall (behind):
Formed by body of C2 (Axis) vertebra &
body of C3 vertebra.
Floor (Below): opens into laryngopharynx at the level
of upper border of epiglottis
Lateral wall:
palatine tonsil - lie in tonsillar fossa- bounded
anteriorly by palatoglossal arch & posteriorly by
palatopharyngeal arch.

14. Palatoglossal arch (Anterior Pillar):
Runs downwards & forwards from
palate to the lateral margin of the tongue.
Palatopharyngeal arch (Posterior Pillar):
Runs downwards & backwards to the
pharyngeal wall where it fades out

15. Anterior wall presents:
(i) Lingual tonsil: formed by numerous nodules of
lymphoid tissue underneath the mucous of pharyngeal
part of dorsum of the tongue.
(ii) Upper free end of epiglottis: behind the tongue.
(iii) Median and lateral glossoepiglottic folds: connecting
anterior surface & edges of the epiglottis, respectively to
the tongue.
(iv) Epiglottic valleculae: shallow fossae between the
median & lateral glossoepiglottic folds.

16. Oropharyngeal Isthmus:
Arched opening between the two palatoglossal folds through which the
oral cavity communicates with the oropharynx.
Boundaries:
Above: Soft palate.
Below: Dorsal surface of the posterior one-third of the tongue.
Lateral: Palatoglossal arch on either side containing palatoglossus muscle.

18. Palatine tonsils (tonsils): mass of lymphoid tissue
lie in tonsillar fossa between anterior & posterior pillars.
Boundaries of the Tonsillar Fossa(Sinus)
Anterior: Palatoglossal arch containing palatoglossus muscle
Posterior: Palatopharyngeal arch containing palatopharyngeus
muscle.
Apex: Soft palate, where both arches meet.
Base: Dorsal surface of the posterior one-third of tongue.
Lateral wall (or tonsillar bed): Superior constrictor muscle

19. Tonsillar Bed
From within outwards:
(a) pharyngobasilar fascia, (b) superior constrictor muscle (c) buccopharyngeal fascia
(d) lower part the styloglossus and (e) glossopharyngeal nerve

20. Medial surface:
• Lined by non-keratinized stratified squamous epithelium.
• It dips into the substance of tonsil forming crypts (12-15).
• Crypts situated near upper part of the tonsil is very large &
deep- crypta magna or intratonsillar cleft.
Lateral surface:
• covered by fibrous tissue- tonsillar hemicapsule.
• peritonsillar space :
- formed by loose areolar tissue between capsule & bed
of tonsil
-plane of dissection during tonsillectomy.
-site of collection of pus in peritonsillar abscess.

21. Anterior border: Passes underneath palatoglossal arch.
Posterior border:Passes underneath palatopharyngeal arch.
Upper pole: It extends up into the soft palate.
Lower pole: It is attached to the tongue by suspensory ligament of the tonsil
Superior constrictor separates lateral surfaceof tonsil from the following structures:
(a) Facial artery & two of its branches, Ascending palatine and tonsillar.
(b) Styloglossus muscle and glossopharyngeal nerve.
(c) Styloid process.
(d) Angle of mandible and medial pterygoid muscle.
(e) Submandibular salivary gland.

22. Arterial Supply of the Tonsil:
1. Tonsillar artery -Branch of facial artery, enters the
lower pole of tonsil by piercing the superior
constrictor.
2. Ascending palatine - branch of facial artery
3. Dorsalis linguae arteries -branches of lingual artery
4. Ascending pharyngeal artery -branch of external
carotid artery
5. Greater palatine (descending palatine) -branch of
maxillary artery.

23. Venous Drainage:
Drain into paratonsillar vein that descends from the soft palate across the tonsillar capsule, pierces the
superior constrictor & drain into pharyngeal venous plexus.

24. Lymphatic Drainage :
• Drain into Upper deep cervical lymph nodes,
• particularly jugulodigastric lymph node. tonsillar lymph node- located
below the angle of the mandible.
Nerve Supply :
• Glossopharyngeal nerve & lesser palatine branches of sphenopalatine
ganglion

25. LARYNGOPHARYNX (Pharynx):
Extent: Upper border of epiglottis to the lower border
of cricoid cartilage anteriorly & lower border of C6
vertebra posteriorly.
Location: behind the larynx.
Communication:
Anteriorly: with laryngeal cavity through laryngeal inlet
Inferiorly: with esophagus at pharyngoesophageal
junction.
Boundaries
Anterior wall:
(a) Laryngeal inlet.
(b) Posterior surface of the larynx.
Posterior wall: supported by bodies of C3, C4, C5, & C6
Lateral wall: supported by thyroid cartilage &
thyrohyoid membrane.
Features
(a) Anterior wall presents laryngeal inlet and
below the inlet it is supported by cricoid and
arytenoid cartilages.
(b) Lateral wall presents piriform fossa one on each
side of laryngeal inlet.

26. PIRIFORM FOSSA (smuggler’s Fossa)
Boundaries :
Medial: Aryepiglottic fold
Lateral: thyroid cartilage & thyrohyoid membrane.
Internal laryngeal nerve pierce the thyrohyoid membrane & traverse
underneath the mucous membrane of the floor of the fossa to reach the
medial wall.
Removal of foreign bodies may damage the internal laryngeal nerve leading to
anesthesia in the supraglottic part of the larynx and subsequent loss of
protective cough reflex.

27. PHARYNGEAL WALL: consists of :
1.Mucous membrane/mucosa:
lined by non-keratinized stratified squamous epithelium
2.Submucosa
3. Pharyngobasilar fascia (pharyngeal aponeurosis):
4.Muscular coat (pharyngeal muscles).
5.Buccopharyngeal fascia (loose areolar sheath).

28. Pharyngobasilar fascia (pharyngeal aponeurosis):
-is a fibrous sheet internal to the pharyngeal muscles.
-is thickest in the upper part where it fills the gap between upper border of superior constrictor & the base of
skull and posteriorly where it forms the pharyngeal raphe

29. Pharyngobasilar fascia (pharyngeal aponeurosis):
-is attached to basiocciput, petrous temporal bone, auditory tube, posterior border of the medial pterygoid
plate, & pterygomandibular raphe.
- Inferiorly, it is gradually lost deep to muscles, and hardly extend beyond superior constrictor

30. Muscular coat: consists of
Outer circular layer made up of the three constrictors &
Inner longitudinal layer made up of stylopharyngeus, salpingopharyngeus & palatopharyngeus muscles.

31. Buccopharyngeal fascia:
• Inconspicuous fascia
• covers outer surface of constrictor muscles.
• Above the upper border of superior constrictor, it
blends with the pharyngobasilar fascia
• Between the buccopharyngeal fascia & muscular coat
there are the pharyngeal plexuses of veins and nerves
The fascia is also prolonged forwards to cover the
buccinator muscles- buccopharyngeal fascia.

32. Muscle Origin Insertion Nerve supply
Superior constrictor (a) Pterygoid hamulus
(b) Pterygomandibular raphe
(c) Upper end of mylohyoid
line
(d) Side of the posterior part
of the tongue
(a) Pharyngeal tubercle
(b) Pharyngeal raphe
Pharyngeal branch of the
vagus nerve- carrying fibres
of cranial root of accessory
nerve

33. Muscle Origin Insertion Nerve supply
Middle constrictor (a) Lower part of the
stylohyoid ligament
(b) Lesser cornu of hyoid
(c) Upper border of greater
cornu of hyoid
pharyngeal raphe Pharyngeal branch of the
vagus nerve - carrying fibres
of cranial root of accessory
nerve

34. Muscle Origin Insertion Nerve supply
Inferior constrictor
(a) Thyropharyngeus
(a) Oblique line of thyroid
cartilage
(b) Tendinous band between
the thyroid (inferior)
tubercle and cricoid
cartilage
Pharyngeal raphe a. Pharyngeal branch of the
vagus nerve - carrying fibres
of cranial root of the
accessory nerve
b) External laryngeal nerve

35. Muscle Origin Insertion Nerve supply
(b) Cricopharyngeus Cricoid cartilage Pharyngeal raphe Recurrent laryngeal nerve

36. Killian 's dehiscence :
weak part lies below the level of
vocal folds or upper border of the
cricoid lamina and is limited inferiorly
by cricopharyngeal sphincter..
Pharyngeal diverticula develop due to
neuromuscular incoordination.
Thyropharyngeus -pharyngeal plexus.
Cricopharyngeus- recurrent laryngeal
nerve
If cricopharyngeus fails to relax when
thyropharyngeus contracts,the bolus
of food is pushed backwards &
produce a diverticulum.

37. Muscle Origin Insertion Nerve supply
Stylopharyngeus Medial surface of styloid process Posterior border of lamina ofthyroid
cartilage
Glossopharyngeal (IX) nerve
Salpingopharyngeus Lower part of the cartilage of
auditory tube
Posterior border of lamina of
thyroid cartilage
Cranial root of XI th cranial
nerve by pharyngeal plexus

38. Muscle Origin Insertion Nerve supply
Palatopharyngeus From the upper surface
of the palatine aponeurosis
Posterior border of the lamina of thyroid
cartilage
Cranial root of XI th cranial
nerve by pharyngeal plexus

39. Gap Structures passing
through them
Between the base of skull &
superior constrictor (sinus
of Morgagni)
• Auditory tube
• Levator palati muscle
• Ascending palatine artery
Between superior & middle
constrictors
• Stylopharyngeus muscle
• Glossopharyngeal nerve
Between the middle and
inferior constrictors
• Internal laryngeal nerve
• Superior laryngeal vessels
Between lower border of
inferior constrictor &
esophagus
• Recurrent laryngeal nerve
• Inferior laryngeal vessels

40. PHARYNGEAL PLEXUS OF THE NERVES
-lies on the posterolateral aspect of pharynx over the middle constrictor underneath the buccopharyngeal
fascia.
Formed by:
1. Pharyngeal branch of vagus nerve carrying fibres of cranial root of accessory nerve
2. Pharyngeal branch of glossopharyngeal nerve.
3. Pharyngeal branch from superior cervical sympathetic ganglion
Superior cervical
sympathetic
ganglion

41. NERVE SUPPLY OF THE PHARYNX
Motor:
All the pharyngeal muscles are supplied by:
cranial root of accessory nerve (via pharyngeal
branch of vagus and pharyngeal plexus),
Except
Stylopharyngeus - glossopharyngeal nerve.
Sensory:
1. Nasopharynx, by maxillary division of
trigeminal nerve.
2. Oropharynx, by glossopharyngeal nerve.
3. Laryngopharynx, by internal laryngeal nerve.

42. ARTERIAL SUPPLY OF THE PHARYNX
1. Ascending pharyngeal artery
- external carotid artery
2. Ascending palatine & tonsillar artery
– facial artery
3. Greater palatine and pharyngeal artery
- maxillaryartery
4. Lingual artery - external carotid artery

43. VANOUS DRAINAGE:
into pharyngeal venous plexus- drains into internal jugular vein.
LYMPHATIC DRAINAGE
drained into the upper and lower deep cervical lymph nodes.

44. PALATE
forms a partition between nasal & oral cavities.
Hard palate: anterior four-fifth of palate
Soft palate: Posterior one-fifth of palate.
Hard palate: partition between nasal & oral cavities.
--Anterior two-thirds- palatine processes of maxillae
--posterior one-third by horizontal plates of
palatine bones
Mucus membrane in anterior part of hard plate is
thrown into 3 or 4 transverse palatine folds/ rugae
but posteriorly it is comparatively smooth.

45. Arteries: Greater palatine branch of maxillary artery
Veins: Drain into the pterygoid plexus of veins.
Nerves: Greater palatine and nasopalatine nerve
Lymphatics: Drain to upper deep cervical nodes; partly
to retropharyngeal nodes.

46. Soft palate: movable, muscular fold attached to posterior margin of
hard palate
• Its median part is prolonged downward as conical projection-
Uvula.
• Median palatine raphe extends from uvula to incisive papilla—
slight elevation behind the incisive fossa.
• lateral margin are continuous with two folds of mucous membrane.
Anterior lateral margin palatoglossal fold/ arch:
connects palate to lateral margin of posterior part of tongue .
Posterior lateral margin palatopharyngeal fold/ arch:
connects palate to wall of pharynx .

47. Muscle present in soft palate:
•Tensor veli palatini
•Levator veli palatini
•Musculus uvalae
•Palatoglossus
•Palatopharyngeus
All the muscles are extrinsic except
musculus uvulae.
All muscles of are supplied by cranial part of accessory nerve through pharyngeal branch of vagus nerve
except tensor palati which is supplied by- Mandibular nerve.

48. THANK YOU

49. PHARYNGEAL SPACES
These are potential spaces in relation to pharynx,
viz.
1. Retropharyngeal space: It is situated behind
the pharynx and extends from the base of the
skull above to the bifurcation of trachea
below.
2. Parapharyngeal space: It is situated on the side
of the pharynx.
It contains carotid vessels, internal jugular
vein, last four cranial nerves, and cervical
sympathetic chain.