Boundaries of nasal cavity
Roof:
Anterior Part
Boundaries
- Nasal cartilage
- Nasal bone 3. Frontal bone
Middle Part: cribriform plate of ethmoid. Posterior Part: body of the sphenoid bone
Floor: Hard palate Medial wall: nasal septum formed
of 3 par 1. Septal cartilage: anterior
- Vomer: posterior
- Perpendicular plate of ethmoid: superi
Lateral wall: contains:
- 3 elevations called conchae:
Superior, middle and inferior. The superior & middle conchae are processes of ethmoid bone. The inferior
concha is a separate bone of the skull.
- 4 spaces: recess and 3 meatuses
a. Sphenoethmoidal recess: above the
superior concha. b. Superior meatus: below the
superior choncha
c. Middle meatus: below the middle choncha
d. Inferior meatus: below the inferior
choncha
- The middle meatus contains:
a. Bulla ethmoidalis: elevation made by the middle ethmoidal air sinus.
b. Hiatus semilunaris: groove below
the bulla ethmoidalis.
c. Infundibulum: anterior extension of the hiatus semilunaris.
Openings into lateral wall of nose
- Sphenoethmoidal Recess: sphenoidal air sinus
- Superior Meatus: posterior ethmoidal sinus
- Middle Meatus:
Sphenoidal sinus
a. Middle ethmoidal sinus: into the bulla b. Anterior ethmoidal sinus: into the
anterior part of the hiatus semilunaris
e. Maxillary sinus: into the posterior part of
the hiatus semilunaris d. Frontal sinus: into the infundibulum
- Inferior Meatus: Nasaolacrimal duct
N supply to lateral nasal wall
Lateral Wall:
- Upper Part: olfactory nerves
- Anterior Part: anterior ethmoidal nerve from nasociliary nerve (ophthalmic nerve). 3. Remaining Part: nasal branches of the greater palatine nerve & sphenopalatine
N supply to nose skin
Skin of the Nose: by
(1. ) Infratrochlear nerve: from the ophthalmic nerve
2. External nasal nerve: from the ophthalmic nerve 3. Infraorbital nerve: from the maxillary nerve
N supply to nasal septum
Septum:
- Upper Part: olfactory nerves
- Anterior Part: anterior ethmoidal nerve from the
nasociliary nerve (ophthalmic nerve) 3. Remaining Part: nasopalatine nerve from maxillary
nerve. It carries secretory fibers to the nasal glands.
Littles area of epistaxis
Anteroinferior of septum Anastomosis of Ant eth A Septal A Sphenopalatine A
Blood supply of nasal cavity
2 from the OPHTHALMIC artery:
- Anterior ethmoidal artery 2. Posterior ethmoidal artery
2 from the MAXILLARY artery: 3” part
- Sphenopalatine artery main supply
- Greater palatine artery
2 from the FACIAL artery:
- Lateral nasal artery
- Septal branch of superior labial artery,
Clinical Importance of Nasal Sinuses
Infection from nasal sinusitis can spread to surrounding areas:
- Frontal sinusitis brain abscess and meningitis
- Ethmoidal sinusitis orbital abscess.
