Atlas of Human Anatomy by Netter

GUIDE

Head and Neck: Nasal Region

Nasal region

External nose

Nasal cavities

Divided by nasal septum

Filter, humidify and warm air

Contain specialised olfactory mucosa

Receive secretions from paranasal sinuses and nasolacrimal duct

Includes related paranasal sinuses

External Nose
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The nose is composed primarily of cartilages except at the "bridge" of the nose where the nasal bone resides. Anteriorly, the air enters or leaves the
nose via the nares, which open into the nasal vestibule, whereas posteriorly the nasal cavity communicates with the nasopharynx via paired
apertures called the choanae.

Composed of bone and hyaline cartilage Bones

Paired nasal bones

Frontal processes of maxilla

Nasal part frontal bone

Cartilages

Paired lateral cartilages

Paired alar cartilages

Septal cartilage

Associated muscles dilate and flatten nares (nostrils)

Nasalis

Compressor nares

Dilator nares

Innervation ophthalmic and maxillary divisions of trigeminal nerve (cranial nerve [CN] V 1 and V 2 )

Blood supply

Ophthalmic artery

Facial artery

Venous drainage

Facial veins → internal jugular veins

Ophthalmic veins → cavernous sinus

Nasal septum

The nasal cavity is separated from the cranial cavity by portions of the frontal, ethmoid, and sphenoid bones, and from the oral cavity inferiorly by the
hard palate. A nasal septum, usually deviated slightly to one side or the other, divides the nasal cavity into right and left chambers. The anterior third
of the nasal septum is cartilaginous and the posterior two thirds is bony.

Divides nasal cavity into two chambers

Composed of

Bone

Vomer

Perpendicular plate of ethmoid

Septal cartilage

Septal cartilage articulated with edges of bony septum

Nasal Cavity
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The lateral wall of the nasal cavity is characterized by three shell-like conchae, or turbinates, that protrude into the cavity, and along with their
covering of nasal respiratory epithelium, they greatly increase the surface area for warming, humidifying, and filtering the air. At the most superior
aspect of the nasal cavity resides the olfactory region, with its olfactory epithelium and specialized sensory cells for the detection of smells.

Each cavity narrow above and wider below, separated from each other by nasal septum

Extend from nares to choanae

Naris = external opening of nose

Choana = opening into pharynx

Vestibule

First part of cavity

Lined with skin with hairs

Bounded laterally by alar cartilages

Limen nasi

Crescentic line

Marks upper limit of vestibule

Nasal mucosa

Lines nasal cavities except for vestibule

Bound to periosteum and perichondrium of surrounding bones and cartilages

Extends into all chambers, cavities and sinuses communicating with nasal cavities