2. CONTENTS
INTRODUCTION
DEVELOPMENT OF PHARYNX
STRUCTURE OF PHARYNX
ANATOMICAL EXTENSION OF NASOPHARYNX
BLOOD SUPPLY
NERVE SUPPLY
LYMPHATIC DRAINAGE
HISTOLOGY
APPLIED ANATOMY
REFRENCES
3. INTRODUCTION
• PHARYNX
• Pharynx is a wide musculomembranous tube situated behind the nasal
cavities, the mouth and the larynx.
• DIMENSIONS OF PHARYNX
• Length
• 12-14 cm in length extending from the cranial base to the level of sixth
cervical vertebra and the lower border of the cricoid cartilage.
• Width
• Greatest superiorly measuring 3.5 cm.
• At its junction with the oesophagus it is reduced to about 1.5 cm this
being the narrowest part of the alimentary canal.
5. DEVELOPMENT
The primitive gut extends
from the buccopharyngeal
membrane cranially to the
cloacal membrane caudally.
Divided into 4 parts-
1-The pharynx
2-The foregut
3-The midgut
4-the hindgut
The pharynx extends from
the buccopharyngeal
membrane to the
tracheobronchial
diverticulum.
6. • Divided into
1- upper part nasopharynx
2-middle part the oropharynx
3-the lower part the
laryngopharynx
7. STRUCTURE OF PHARYNX
• The wall of pharynx is
composed of five layers from
within outwards:
1- MUCOSA
2- SUBMUCOSA
3-PHARYNGOBASILAR FASCIA
4-MUSCULAR COAT
5-BUCCOPHARYNGEAL FASCIA
8. 3-PHARYNGO-BASILAR FASCIA-
• The intermediate fibrous layer
which is thick above where the
muscular fibres are absent.
• Firmly connected to
A- Basilar occipital and petrous
temporal bones medial to
carotid canal.
B –Curving under the auditory
tube and forward to the
posterior border of the medial
pterygoid plate and
pterygomandibular raphae.
C- As it descends its thickness
diminishes.
D- Posteriorly attached to
pharyngeal tubercle and
descends as Medial Pharyngeal
raphae of constrictors .
9. 4- THE MUSCULAR COAT-
3 PAIRS OF CONSTRICTOR-
• SUPERIOR CONSTRICTOR
• MIDDLE CONSTRICTOR
• INFERIOR CONSTRICTOR
INNER LONGITUDNAL LAYERS
STYLOPHARYNGEUS
SALPINGOPHARYNGEUS
PALATOPHARYNGEUS.
10. 5-BUCCOPHARYNGEAL FASCIA:
Covers the outer surface of
constrictors of pharynx.
Extends forward across the
pterygomandibular raphae to cover
th Buccinator.
11. •Parts of Pharynx
• Cavity of pharynx is divided
into 3 parts
a. The nasal part,
NASOPHARYNX
b. The oral part, OROPHARYNX
c. The laryngeal part
,LARYNGOPHARYNX
12. NASOPHARYNX
Behind the nasal cavity.
Extends from SKULL BASE superiorly to the SOFT PALATE inferiorly.
Communicates with nasal cavity with two posterior nasal apertures
which are 25mm vertically and 12.5mm transversely and are
separated by posterior edge of nasal septum.
Nasal and oral part communicate through the PHARYNGEAL
ISTHMUS,which is closed during swallowing by elevation of palate and
contraction of PALATOPHARYNGEAL SPHINCHTER.
LATERAL WALL presents pharyngeal opening of the AUDITORY TUBE,
• 10-12.5mm behind and and a little below the posterior end of the
inferior nasal concha.
15. ROOF OF NASOPHARYNX
Supported mainly by
basilar occipital bone
posteriorly.
Posterior part of the
body of the sphenoid
anteriorly.
Pharyngeal tonsil, a
lymphoid mass which lies
in the submucosa of the
upper part of this surface
and it is best developed
in childhood.
16. PHARYNGEAL TONSIL
Visible during the later fetal months.
Increases in size up to 6 or 7 years and
then usually begins to atrophy.
In a child of 18 months it is a forward
directed pyramidal prominence, with its
apex near the nasal septum and its base
at the junction of nasopharyngeal roof
and posterior wall.
It consist of folds radiating antero-laterally
from a median recess,the PHARYNGEAL
BURSA, which ascends backward into its
substance.
It represents attachment of notochord to
the pharyngeal endoderm during
embryonic life.
The mucosal folds are mainly diffuse
lymphoid tissue,but also contain deep
mucous glands.
17. APPLIED ANATOMY
In young children lymphoid hypertrophy in nose and
nasopharynx(ADENOIDS),with or without enlargement of the palatine
tonsil, may obstruct nasal respiration.
The mouth has to be kept open to breathe.(MOUTH BREATHING).
The hard palate and alveolar arch are then habitually out of contact
with the lingual dorsum.
Develop an abnormally high arch and forward projection.
The hard palate becomes transversely narrow and projecting alveolar
process afford little room for the permanent teeth which leads to
crowding and overhang the lower teeth.
18. Maxillary surfaces
appears pinched
together,with narrowing
of nasal cavities and
maxillary air sinuses.
Upper lip is drawn up
exposing the projecting
upper incisors.
The face is lengthened
by dropping of the lower
jaw leading to .
CAHRACTERISTIC FACIAL
EXPRESSION (ADENOID
FACIES)
19.
20. CLINICAL SIGNIFICANCE OF
NASOPHARYNGEAL BURSA
An abscess can form in the
bursa –TORNWALDT’S
DISEASE.
A TORNWALDT’S CYST
develops if the embryonic
remanant gets obstructed.
21.
22. FLOOR OF NASOPHARYNX
Formed by soft palate
anteriorly.
Deficient posteriorly called
as nasopharyngeal
isthmus via which it
communicates with the
oropharynx.
PHARYNGEAL ISTHMUS
remains closed during
swallowing by the
elevation of palate and
contraction of the
PALATOPHARYNGEAL
SPHINCTER.
23. PASSAVANT’S RIDGE
• The Superior pharyngeal
constrictor muscle contracts
to narrow the
nasopharyngeal space.
• TENSOR VELI PALATINI
muscle tenses the soft palate
to prevent distortion.
• The LEVATOR VELI PALATINI,
PALATOPHARYNGEUS AND
SALPINGOPHARYNGEUS
elevate it postero-superiorly.
24. • The lateral and posterior
walls around the
nasopharyngeal isthmus are
then made taut by
contraction of the
palatopharyngeal sphincter
muscle fibres( consist of
skeletal muscle fibres of
the most superior aspect of
the palatopharyngeus
muscle. These fibres forms
an incomplete circle along
the lateral and posterior
walls of the
nasopharyngeal isthmus at
the level of C1 vertebra.)
• THE LATTER ACTION FORMS
PASSAVANT’S RIDGE.
• These series of action prevent
communication b/w the
nasopharynx and the
oropharynx during swallowing.
25. CLINICAL SIGNIFICANCE
Failure to close the naso-oropharyngeal communication
results in a condition known as velo-pharyngeal insufficiency.
Can be caused by variety of disorders (Structural, Genetic,
Functional or Accquired.)
Very often associated with a Cleft palate.
Parents usually bring in infants with this complication due to
food and liquid coming through the nose during feeding and
vomiting.
Older individuals may present with recurrent sinus and ear
infections due to ingested contents flowing back into the
nasal sinus and the ostium pharyngeum respectively
29. ANTERIOR EXTENT OF NASOPHARYNX
Anteriorly it communicates with the nasal cavity,through the
two posterior nasal apertures,which are each 25mm
vertically,12.5mm transversely.
Seperated by posterior edge of nasal septum.
30.
31.
32. POSTERIOR WALL OF NASOPHARYNX
Bounded by
Atlas vertebra
Dens of C2 Vertebra
Superior constrictor
Buccopharyngeal fascia
Retropharyngeal space
Prevertebral fascia
33. • Superior constrictor muscle: A
quadrilateral sheet ,thinner and
paler than others.
• ORIGIN:
• 1 –attached anteriorly to the PTERYGOID
HAMULUS.
•
• 2- PTERYGOMANDIBULAR RAPHAE.
• 3- POSTERIOR END OF THE MYLOHYOID LINE
of the mandible.
• 4-SIDE OF POSTERIOR PART OF THE TONGUE.
• INSERTION:
• 1-MEDIAN PHARYNGEAL RAPHAE
• 2-SOME FIBRES ARE PROLONGED BY AN
APONEUROSIS TO THE PHARYNGEAL
TUBERCLE ON THE BASILAR PART OF
OCCIPITAL BONE
34.
35. RELATIONS OF SUPERIOR CONSTRICTOR
• EXTERNALLY:
• PREVERTEBRAL FASCIA AND MUSCLES
• THE ASCENDING PHARYNGEAL ARTERY
• THE PHARYNGEAL VENOUS PLEXUS
• GLOSSOPHARYNGEAL AND LINGUAL NERVES
• STYLOGLOSSUS AND MIDDLE CONSTRICTOR
• MEDIAL PTERYGOID
• STYLOHYOID LIGAMENT
• STYLOPHARYNGEUS
• INTERNAL CAROTID ARTERY
• SYMPATHETIC TRUNK
• HYPOGLOSSAL NERVE
• INTERNAL JUGULAR VEIN
• STYLOID PROCESS
36.
37. INTERNAL RELATION OF SPC
PALOTOPHARYNGEUS
THE TONSILLAR CAPSULE
PHARYNGOBASILLAR
FASCIA
38. • SUPERIORLY:
IT IS SEPARATED FROM THE
CRANIAL BASE BY A
CRESENTRIC INTERVAL
CONTAINING LEVATOR VELI
PALITINI.
TENSOR VELI PALITINI.
THE AUDITORY TUBE.
39. • INFERIORLY:
ITS BORDER IS SEPERATED FROM
MIDDLE CONSTRICTOR BY
• 1- STYLOPHARYNGEUS
• 2- GLOSSOPHARYNGEAL NERVE
41. NERVE SUPPLY AND ACTION
• NERVE SUPPLY:
THE PHARYNGEAL BRANCH OF VAGUS NERVE VIA THE
PHARYNGEAL PLEXUS .
• ACTION OF SPC:
CONSTRICT WALL OF PHARYNX DURING SWALLOWING.
42. BUCCOPHARYNGEAL FASCIA
The buccopharyngeal fascia is
a fascia in the head.
Parallel to the carotid sheath and
along its medial aspect the
pretracheal fascia gives off a thin
lamina, the buccopharyngeal fascia,
which closely invests the constrictor
muscles of the pharynx and is
continued forward from
the constrictor pharyngis
superior onto the buccinator.
It is attached to the prevertebral
layer by loose connective
tissue only, and thus an easily
distended space,
the retropharyngeal space, is found
between them.
43.
44. RETROPHARYNGEAL SPACE
The retropharyngeal space is
a potential space of the head and
neck, bounded by
the buccopharyngeal
fascia anteriorly and the alar
fascia posteriorly. Together with
the lateral pharyngeal space, these
spaces are termed
the parapharyngeal spaces.
It contains the retropharyngeal
lymph nodes.
45. PRE-VERTEBRAL FASCIA
The prevertebral fascia is fixed
above to the base of the
skull, and below it extends
behind the esophagus into
the posterior mediastinal
cavity of the thorax.
It descends in front of
the longus colli muscles.
The prevertebral fascia is
prolonged downward and
laterally behind the carotid
vessels and in front of
the scalene muscles.
46.
47. LATERAL WALL OF PHARYNX
Each lateral wall presents
a pharyngeal opening of
the auditory tube 10-
12.5mm behind and little
below the posterior end
of the inferior nasal
concha.
It is somewhat triangular
in shape,this opening is
bounded above and
behind by the TUBAL
ELEVATION.Formed over
the underlying pharyngeal
end of the cartilage of the
tube.
48. A vertical
SALPINGOPHARYNGEAL FOLD
OF MUCOSA descends from
the tubal elevation , covering
the SALPINGOPHARYNGEUS
MUSCLE in the wall of the
pharynx.
A smaller SALPINGOPALATINE
FOLD ,extends from the
anterosuperior angle of the
tubal elevation to the soft
palate.
The LEVATOR VELI PALITINI
entering the soft palate
produces an elevation of the
mucosa immediately below
the tubal opening.
50. LATERAL PHARYNGEAL RECESS/ FOSSA
OF ROSENMULLER
The anatomy of the fossa was
first described in 1808 by
Johann Christian
Rosenmüller.
The fossa of Rosenmüller is a
bilateral projection of the
nasopharynx just below the
skull base. It is also called the
lateral pharyngeal recess or
simply the pharyngeal recess.
The fossa is covered by
nasopharyngeal mucosa .
The lateral pharyngeal recess,
or the fossa of Rosenmüller, is
located behind the torus
tubarius
51. BOUNDARIES OF THE FOSSA OF
ROSSENMULLER
• ANTERIORLY:
• 1-Eustachian tube.
• 2-Levator palatini
muscle.
• POSTERIOR:
• 1-Posterior wall of
nasopharynx.
• 2-Retropharyngeal
space.
52. • LATERAL:
• 1-Parapharyngeal space.
• 2-Tensor veli palatini muscle.
• 3-Mandibular nerve
• 4-Pre styloid compartment
of Parapharyngeal space.
• INFERIORLY:
• 1-Upper edge of the superior
constrictor muscle.
• MEDIALLY:
• 1- Nasopharynx
53. •POSTERO-LATERAL OR
APEX-
• 1-CAROTID CANAL OPENING
AND PETROUS APEX
POSTERIORLY.
• 2-FORAMEN OVALE AND
SPINOSUM LATERALLY.
•SUPERIORLY:
• 1-FORAMEN LACERUM
• 2-FLOOR OF CAROTID CANAL
55. CLINICAL SIGNIFICANCE OF FOSSA OF
ROSENMULLER
1-NASOPHARYNGEAL CARCINOMA:
. It was determined to be the most common site of origin of nasopharyngeal
carcinoma. 50% of cases.
Loh et al attempted to study the anatomy of the fossa on 23 CT scans.
They found that the fossa projects at about a 45-degree angle from the sagittal plane
and ranges in length from 1.7 mm to 18.8 mm with a relatively narrow orifice.
This led them to conclude that the fossa was often too deep and narrow for clinical
inspection with a nasopharyngoscope and could constitute a blind spot in the
postnasal space, especially the floor of the fossa.
This had clinical implications in the early detection of nasopharyngeal carcinoma.
Deep infiltration of NPC was most commonly to the intracranial region, usually
through the foramen lacerum and the foramen ovale.(Trotter's syndrome is a
cluster of symptoms associated with certain types of advanced nasopharyngeal
carcinoma)
58. • LYMPHATIC SPREAD-Most common to upper,
middle deep cervical & retropharyngeal lymph
nodes.
59. TREATMENT OF NPC
The main treatment for NPC is radiation therapy. It is often
given in combination with chemotherapy. This approach
may be called concomitant chemoradiotherapy
Surgery for NPC is occasionally used, mainly to remove lymph nodes
after chemoradiotherapy or to treat NPC that has come back after
initial treatment.
60. SINUS OF MORGAGINI
• A large gap between the upper
concave border of the superior
constrictor and the base of the skull
is semi-lunar and is known as the
SINUS OF MORGAGINI.
• It is closed by the upper strong part
of the pharyngo basilar fascia.
• STRUCTURES PASSING
THROUGH THIS GAP:
1- THE AUDITORY TUBE
2-THE LEVATOR VELI PALITINI MUSCLE
3-THE ASCENDING PALATINE ARTERY
61. SINUS OF MORGAGNI
Space between base of
skull & sup.connstictor.
Through it enters-
Eustachian tube
Tensor &Levator veli
palatini muscle
Asc. Palatine
artery.
a-mucosa
b-pharyngobasilar fascia
c-muscular coat
d-buccopharyngeal fascia
62. CLINICAL SIGNIFICANCE OF SINUS OF MORGAGINI
• In nasopharyngeal carcinoma, the tumor may extend laterally and
involve this sinus.
• It can easily breach into the PARAPHARYNGEAL SPACE.
63. BLOOD SUPPLY
• ARTERIES THAT SUPPLY
UPPER PARTS OF THE
PHARYNX:
1-THE ASCENDING
PHARYNGEAL ARTERY
2-THE ASCENDING PALATINE
AND TONSILLAR BRANCHES
OF FACIAL ARTERY
3-NUMEROUS BRANCHES OF
MAXILLARY AND LINGUAL
ARTERIES.(all these vessels are
from the external carotid
artery)
64. •ARTERIES SUPPLYING
LOWER PART OF THE
PHARYNX
1-PHARYNGEAL BRANCHES
FROM THE INFERIOR THYROID
ARTERY(originating from the
thyrocervical trunk of the
subclavian artery.)
65. VEINS
VEINS OF THE PHARYNX
FORMS A PLEXUS,WHICH
DRAINS SUPERIORLY INTO
THE PTERYGOID PLEXUS
IN THE INFRATEMPORAL
FOSSA.
INFERIORLY INTO THE
FACIAL AND INTERNAL
JUGULAR VEIN.
66. LYMPHATICS
• Lymphatic vessels from the
pharynx drain into the deep
cervical nodes and include
RETROPHARYNGEAL
(between nasopharynx and
vertebral column),
PARATRACHEAL AND
INFRAHYOID NODES.
• The palatine tonsils drain
through the pharyngeal wall
into THE JUGULODIGASTRIC
NODE in the region where the
facial vein drains into the
internal jugular vein (and
inferior to the posterior belly
of the digastric muscle).
67.
68. NERVE SUPPLY
• Motor and most sensory innervation (except for the nasal region) of
the pharynx is mainly through branches of the vagus [ X ] and
glossopharyngeal [ IX ] nerves, which form a plexus in the outer
fascia of the pharyngeal wall.
• PHARYNGEAL PLEXUS:
The pharyngeal plexus is formed by:
■ the pharyngeal branch of the vagus nerve [ X ]
■ branches from the external laryngeal nerve from the superior
laryngeal branch of the vagus nerve [ X ] and
■ pharyngeal branches of the glossopharyngeal nerve [ IX ] .
69. • The pharyngeal branch of the vagus nerve [ X ] originates from the upper
part of its inferior ganglion above the origin of the superior laryngeal nerve
and is the major motor nerve of the pharynx.
• All muscles of the pharynx are innervated by the vagus nerve [ X ]
mainly through the pharyngeal plexus, except for the
stylopharyngeus, which is innervated directly by a branch of the
glossopharyngeal nerve [ IX ] .
70. SENSORY NERVE SUPPLY
• Each subdivision of the pharynx has a different sensory innervation:
1-The nasopharynx is innervated by a pharyngeal branch of the
maxillary nerve [ V 2 ] that originates in the pterygopalatine fossa and
passes through the palatovaginal canal in the sphenoid bone to reach
the roof of the pharynx.
2-The oropharynx is innervated by the glossopharyngeal nerve [ IX ]
via the pharyngeal plexus.
3- The laryngopharynx is innervated by the vagus nerve [ X ].
71.
72. HISTOLOGY
1-Nasopharyngeal epithelium is-
• CILIATED PSEUDO STRATIFIED
COLUMNAR EPITHELIUM
containing
• GOBLET CELLS AND RECEIVING
SUBMUCOUS GLANDS.
2- The oro and laryngo pharynx it is-
• NON-KERATINIZED STRATIFIED
SQUAMOUS EPITHELIUM.
3- A narrow transitional zone is
present of CUBOIDAL EPITHELIUM,
the cilia being imperfect or absent.
73. FUNCTIONAL CO-RELATION
1-The mucus helps maintain epithelial
moisture and traps particulate material
and pathogens moving through the
airway.
2-The oropharynx, are also subject to
the abrasive swallowing of food. To
prevent the destruction of the
respiratory epithelium in these areas, it
changes to stratified squamous
epithelium, which is better suited to
the constant sloughing and abrasion.
3-The squamous layer of the
oropharynx is continuous with
the esophagus.
74. REFERENCES
Gray’s Anatomy 37th edition.
DiFIORE’s Atlas of Histology.
Langman’s Medical Embryology11th edition.
Grant’s Atlas of Anatomy.
Fank.H.Netter Atlas of Human Anatomy.-4th Edition
Gray’s Anatomy for Students 2nd Edition.
BD Chaurasia’s Human Anatomy Vol 3- 5th edition.