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The Nose
The Nasopharynx
The Paranasal sinuses
To describe the external nose.
To define the nasal cavity & its contents.
To describe the nasal part of the pharynx.
To list the paranasal sinuses.
The External Nose:
Surface anatomy:
The External Nose:
Skeleton:
1-The bony part: formed by nasal bones
2-The cartilagenous part:
A) Lateral nasal cartilage; attached to lower
border of nasal bone
B) Alar cartilage; from rounded part of the
nostril
A
B
Arterial supply:
1- Facial artery.
2- Infraorbital artery.
Veins:
Accompany arteries.
Nerves:
1- Midline; Infratrochlear & external
nasal (Va)
2- Lateral side; infraorbital (Vb)
The Nasal Cavity:
Skeleton:
1- Lateral wall:
-Sphenoid
-Palatine
-Ethmoid
-Maxilla
-Inferior concha
E
M
IC
P
S
2- Floor:
-Formed by the hard palate.
-Fixes the septum by the maxillary
crest
3- Roof:
-Is formed by the cribriform plate
-Communicates with anterior cranial
fossa
-Lined with olfactory neuro-epithelium
-Olfactory nerves leave the roof
through the cribriform plate to the
brain
-Olfaction takes place in the roof
Anosmia:
-Any pathology blocking the nose
prevent odours from reaching the roof
-May be of neurological origin
4-Medial wall (septum):
-Perpendicular plate of ethmoid
-Vomer
-Septal cartilage
-Maxillary crest
E
V
SC
Deviated nasal
septum
Parts of the nose:
•The vestibule; is the skinny part of the nasal cavity
•The choanae; are the posterior nasal apertures which open to the
nasopharynx
Congenital choanal atresia
* Unilateral
* Bilateral
•The conchae (Turbinates):
-Three scroll-like projections in the lateral wall of the nose
-The upper two are parts of the ethmoid while the lower is a separate bone
-Their covering mucosa is highly vascular & contain erectile tissue so their
size is not fixed
-Functions; increase mucosal area & protect the meatuses
Case scenario …
A 35 years old lady consulted the ENT
surgeon for severe nasal obstruction of
few months duration, her husband said
that her snoring at night is intolerable!
On examination, the physician found
severe deviation in her nasal septum, with
hypertrophied inferior turbinates.
CT scan confirmed the diagnosis, &
revealed intact paranasal sinuses.
She was prepared for turbinectomy &
septoplasty.
Concha bullosa (normal 50%):
-Air filled cavity within turbinate
-May cause nasal obstruction
•Meatuses:
-Each concha overlies a meatus
-Consequently we have superior,
middle & inferior meatuses
-Inferior meatus receives the
nasolacrimal duct from the orbit
-Other meatuses receive
openings of the paranasal
sinuses
-Spheno-ethmoidal recess is the
space between the superior
concha & nasal roof
-The middle meatus is composed of
two structures:
1- Bulla ethmoidalis: spherical bulge
fromlateral nasal wall
2- Hiatus semilunaris: crescentic cleft
inferior to the bulla
Osteomeatal complex:
-Radiological term referring to the site
of these structures
-Its obstruction predispose to chronic
sinusitis
1
2
Nerve supply:
Lateral wall: (in quadrants)
1- Anterior ethmoidal n.
2- Anterior superior alveolar n.
3- Posterior superior lateral nasal n.
4- Greater & lesser palatine n.
•(1) is ophthalmic branch
•(2) is maxillary branch
•Others are pterygopalatine
ganglion branches
1
2
3
4
The septum: (in halves)
1- Nasopalatine nerve:
-Branch of pterygopalatine ganglion
-Supplies postero-inferior half
2- Anterior ethmoidal nerve:
-Branch of ophthalmic nerve
-Supplies anterosuperior quadrant
Arterial supply:
Like nerve supply
Venous drainage:
*Anterior ½; anterior facial vein
*Posterior ½; pterygoid v. plexus
Epistaxis “Little’s area”
The pterygopalatine ganglion:
-A parasympathetic ganglion lies in the
pterygopalatine fossa (behind the orbit)
-Its parasympathetic root from facial
nerve (greater petrosal branch)
-Its sensory root from maxillary nerve
-Gives 5 postganglionic branches:
1- Nasopalatine
2- Posterior superior lateral nasal
3- Pharyngeal
4&5- Greater & lesser palatine
The nasopharynx:
•The part of the pharynx lying superior to
the hard palate
•It is completely respiratory
•Its wall is strengthened by the
pharyngobasilar fascia
•Supplied by pharyngeal branch of
pterygopalatine ganglion
Structures in the nasopharynx:
1- Pharyngeal tonsil: just below the roof.
2- Tubal tonsils: around the openings of auditory tubes.
3- Eustachian (auditory) tube openings: one on each side, connect the
nasopharynx to the middle ear cavity.
1
3
2
4- Salpingopharyngeal fold:
muscular fold descends behind
the tubal orifice.
5- Pharyngeal recess: projects
posterolaterally behind the fold.
5
4
Adenoids (Enlarged pharyngeal tonsils)
Eustachian tube dysfunction Causes impaired hearing
The paranasal sinuses:
•Pneumatic areas in the frontal,
ethmoidal, sphenoidal & maxillary
bones.
•Their mucosa is continuous with that
of the nasal cavity through the
meatuses
•The maxillary sinus is well developed
at birth, the frontal & sphenoidal
develop at the 7th year of life while the
ethmoidal develop at puberty.
•Supplied by regional vessels & nerves
•Function !??
The frontal sinuses:
•2 pyramidal sinuses within the frontal bone, rarely symmetrical
•Drain to the anterior part of the hiatus semilunaris
•Supplied by supraorbital & supratrochlear vessels & nerves.
The ethmoidal sinuses:
•3 sinuses in each lateral mass of the ethmoid; anterior, middle & posterior
•They are trabeculated forming air cells
•Anterior & middle drain to the middle meatus
•The posterior drains to the superior meatus
•Anterior & posterior vessels & nerves supply them
ACF
Orb
NC Mx
The sphenoidal sinuses:
•2 sinuses in the body of sphenoid
•Opens in the spheno-ethmoidal recess.
•Supplied by the posterior ethmoidal vessels & nerves
The maxillary sinuses:
•2 sinuses, one occupies each maxillary body
•They are pyramidal cavities with their bases directed to the lateral nasal wall
•The big openings in the lateral nasal wall are blocked by the inferior conchae
•Drain in the posterior part of hiatus semilunaris
•Supplied by superior alveolar, infraorbital & zygomaticofacial vessels & nerves
Applied anatomy:
Sinus pain refers to:
Forehead
Nose
Orbit
Upper teeth
Antral washout