Download Anatomy and physiology of Nose

Anatomy of nose
By: Elaf almutairi, Esraa abdulrahman and Ghada abu jamea
Nose
 Origin:
Originates from the nasofrontal process during 4th to 8th week of IU
life.
 Consists
of :
- External nose.
- Nasal cavity.
The external nose :
Is a pyramidal projection of face .
- Tip
- Root
- Dorsum
- Ala of nose bounding inferiorly a pair of nostrils
-
External nose
 The
external nose has
two elliptical orifices
called the naris
(nostrils) , which are
separated from each
other by the nasal
septum.
The lateral margin, the
ala nasi is rounded
and mobile.
External nose
Osteocartilaginous
framework:
 Bony pyramid – upper 1/3rd
it is responsible for the height of the nose.
It provides the support for the upper
portion of the nose.
Cartilaginous part – lower
2/3rd
 (Upper & lower cartilaginous
vault)

The greater alar
cartilage and the
lesser alar
cartilages give
your tip and
nostrils their
shape.
Blood Supply of Nose
The
skin of the external nose is supplied by
branches of the ophthalmic and the maxillary
arteries
The
skin of the ala and the lower part of the
septum are supplied by branches from the
facial artery which originate from external
carotid artery.
Nerve Supply of the External
Nose
The
infratrochlear and external nasal
branches of the ophthalmic nerve (CN V)
and the infraorbital branch of the
maxillary nerve (CN V) for general
sensation.
Internal nose
Vestibule
of nose
 Nasal
cavity divided into right & left
halves by the nasal septum each half
has a:
Lateral wall
 Medial wall
 Roof
 Floor

LINING MEMBRANE OF INTERNAL NOSE
Vestibule:
Lined
by skin containing hair, hair follicles,
sebaceous glands.
Olfactory region:
Mucous membrane.
Respiratory region:
Mucous membrane shows varible
thickenings.
The Lateral Walls of Nasal Cavity
Marked by 3 projections:
1. Superior concha (turbinate).
2. Middle concha (turbinate).
3. Inferior concha (turbinate).

Lateral wall
The
cavity below
each concha is
called a meatus.
The
small space
above the superior
concha is the
sphenoethmoial
(suprameatal)
recess.
meatus
Sphenoethmoidal
recess
The Lateral Walls of Nasal Cavity
1.
Inferior meatus: nasolacrimal duct.
2.
Middle meatus:
•
Maxillary sinus.
•
Frontal sinus.
•
Anterior ethmoid sinuses.
3.
Superior meatus: posterior ethmoid sinuses.
4.
Sphenoethmoidal recess: sphenoid sinus.
Medial wall
Osteo-cartilaginous
partition between the
two nasal cavities
called nasal septum.
 Formed by:
1. Septal cartilage
(anterior).
2. Perpendicular
plate of ethmoid
bone (superior).
3. Vomer (inferior).

Septal
Cartilage
Vomer
Roof

Narrow & formed (anteroposteriorly) by
the:
1. Nasal bone & cartilage
2. Frontal bone.
3. Cribriform plate of ethmoid bone
4. Body of sphenoid.
•Floor
•Ant. 3/4th formed by palatine process of the
maxilla
•Post. 1/4th formed by the palatine bone.
Blood supply
Blood supply of lateral wall

INTERNAL CAROTID SYSTEM:


1. Anterior ethmoidal.
2. Posterior ethmoidal } Branches of ophthalmic artery.

EXTERNAL CAROTID SYSTEM:


1. Posterior lateral nasal
Branches → From sphenopalatine artery.

2. Greater palatine artery → From maxillary artery.


3. Nasal branch of anterior superior dental
→ From infraorbital
branch of maxillary
Artery.

4. Branches of facial artery to nasal vestibule.

Blood Supply to the Nasal Cavity




From branches of the maxillary artery, one of the
terminal branches of the external carotid artery.
The most important branch is the sphenopalatine
artery.
The sphenopalatine artery anastomoses with the
septal branch of the superior labial branch of the
facial artery in the region of the vestibule(little area).
The submucous venous plexus is drained by veins
that accompany the arteries.
Sphenopalatine a.
Maxillary a.
Nerve Supply of the Nasal Cavity

The olfactory nerves from the olfactory
mucous membrane ascend through the
cribriform plate of the ethmoid bone to the
olfactory bulbs .

The nerves of ordinary sensation are branches
of the ophthalmic division (V1) and the
maxillary division (V2) of the trigeminal nerve.
Nerve Supply of the Nasal Cavity
CN I – Olfactory Nerves (SVA)
Anterior ethmoidal
branch of V1
Cut nasopalatine
branch of V2 to
septum
Posterior nasal
branches of V2
Lymph Drainage of the Nasal Cavity
The lymph vessels draining the vestibule end in
the submandibular lymph nodes.
 The remainder of the nasal cavity is drained by
vessels that pass to the upper deep cervical
nodes.

The paranasal sinuses are cavities found
In the inferior of the maxilla, frontal,
sphenoid ,
And ethmoid bones.
They are lined with mucoperiosteum and
filled with air.
They communicate with the nasal cavity
through relatively small apertures.
Maxillary sinus
Pyramid in shape 15cc Capacity.
Paired and symmetric
Located within the body of the maxilla behind the skin of the cheek.
The roof is formed by the floor of the orbit and the floor related to the
roots of the 2nd premolar and 1st molar teeth.
• The maxillary sinus opens into the middle meatus of the nose.
• It appear radiologically after 5 months from delivery, at age of 15 it
reach full capacity.
•
•
•
•
Frontal sinuses
Paired rarely symmetrical, 7cc capacity.
Contained within frontal bone
Separated from each other by a bony septum .
Each sinus is roughly triangular
Extending upward above the medial end of the eyebrow and backward into
the medial part of the roof of the orbit.
• Opens into the middle meatus
•
•
•
•
•
Sphenoidal sinuses
• Lie within the body of the sphenoid bone
• Below Sella turcica (extends between dorsum sellae and post clinoid processes)
• Opens into the sphenoethmoidal recess above the superior concha.
• Laterally related to ophthalmic nerve , internal carotid artery
So it’s sensitive area for surgeon when they need to remove pituitary gland .
Ethmoidal sinuses
• They are anterior, and posterior
• They are contained within the ethmoid bone,
between the nose and the orbit
• Anterior and middle (drains into middle nasal
meatus)
• Posterior(drain into superior nasal meatus)
• Separated from the orbit by a thin plate of
bone so that infection can readily spread from
the sinuses into the orbit.
Functions of the nose:
1- Respiration.
2- Air-conditioning of inspired air.
3- Vocal resonance.
4- Nasal reflex function.
5- Protection of lower airway.
6- Olfaction.
1.Respiration:
Inspiration: Very little air passes through inferior meatus or olfactory region of nose.
Expiration: The entire air current is not expelled directly through the nares, some
goes through inferior and middle turbinates and this ventilates the sinuses through the
ostia.
Asymmetrical Congestive Response (The Nasal Cycle): Normal physiological
congestion/decongestion cycle alternating between nasal sides every 2–7 hours.
2. Air conditioning of inspired air:
1. Filtration and Purification: The nasal vibrissae,
the mucus membrane and the nasal mucus all help in
trapping small particles.
2. Temperature control: cavernous venous spaces or
sinusoids
in the mucosal membrane help in reducing or
increasing temperature of inspired air to match body
temperature.
3. Humidification: The mucous membrane adjusts the
relative humidity of the inspired air to 75% or more.
3. Protection of lower airway:
 Mucociliary mechanism: the mucus blanket; formed of secretions of goblet
cells and secretory glands lies on cilia and carries microorganisms to the
nasopharynx to be swallowed.
 Enzymes and immunoglobulins: lysosymes, IgA and IgE secreted in nasal
cavity kill bacteria and provide immunity.
 sneezing: protective reflex. Foreign particles which irritate nasal mucosa are
expelled by sneezing.
4.Vocal Resonance: When the nose is blocked the speech becomes denasal.
5. Nasal Reflexes: Nasal function is closely related to pulmonary functions
through nasobronchial and nasopulmonary reflexes. (secretion of salaiva, sneezing, nasal
obstruction and pulmonary resistance, etc.)
6. Olfaction:
Olfactory Pathways:
Peripheral processes of olfactory cells act as sensory receptors
for odorous substances while central processes are grouped into
olfactory nerves which pass through the cribriform plate of
ethmoid and end in the mitral cells of the olfactory bulb. Smell is
then carried through axons of mitral cells of olfactory tract to
the prepyriform cortex and the amygdaloid nucleus where it
reaches consciousness.
Sense of smell can be tested by asking the patient to smell
common odours such as lemon, peppermint, rose, garlic
or cloves from each side of the nose separately, with eyes
closed.
Function of sinuses:
Ventilation of sinuses is paradoxical; they are emptied
of air during inspiration and filled with air during
expiration.
1. Air-conditioning of the inspired air.
2. Resonance to voice.
3. Thermal insulators to protect the delicate structures
in the orbit and the cranium.
4.To lighten the skull bones.
5.To provide extended surface for olfaction.
6.Immunologic defence against microbes.
7. Protect brain against injury by acting as buffers.
Thank you