Nasal cavity
Updates to Article Attributes
The nasal cavity forms part of the aerodigestive tract.
Gross anatomy
The nasal cavity is formed by 1:
- anteriorly: nasal aperture
- laterally: inferior, middle and superior nasal conchae (turbinates)
- superiorly: cribriform plate of the ethmoid bone
- inferiorly: palatal processes of the maxilla and horizontal portion of the palatine bone forming the hard palate
- posteriorly: posterior nasal aperture (choanae) at the
posteirorposterior margin of the bony nasalspetumseptum
In the midline, the nasal cavity is divided into right and left halves by the nasal septum composed of fibrocartilage anteriorly and the vomer and the perpendicular plate of the ethmoid bone posteriorly and inferiorly.
Anteriorly, it is continuous with the nose at the nasal aperture and posteriorly it is continuous with the nasopharynx. Laterally, the three nasal conchae form the three nasal meatusmeati.
Connections
-
superior meatus
- posterior ethmoidal air cells and sphenoid sinuses via the sphenoethmoidal recess 2
-
middle meatus
- frontal sinus via frontal recess
- ethmoid and maxillary sinuses via ostiomeatal complex
- inferior meatus
Blood supply
Arterial supply
The arterial supply of the nasal cavity is rich and derives from both the internal and external carotid arteries 4, 5,5:
- lateral nasal wall
- superior lateral nasal wall: anterior and posterior ethmoidal arteries
- inferior and middle turbinates: sphenopalatine artery
- posterior lateral nasal wall: pharyngeal artery
- nasal septum
- anteriorly: greater palatine artery
-
postero-inferiorlyposteroinferiorly: sphenopalatine artery - superiorly: anterior and posterior
ethmoidethmoidal arteries
- floor
- greater palatine and superior labial arteries
Rich arterial supply results in two anastomotic areas, which are common sites of epistaxis 4:
- Woodruff area: anastomosis of sphenopalatine and pharyngeal arteries in the inferior lateral nasal wall, posterior to the inferior turbinate
-
Kiesselbach plexus: anastomosis of the anterior ethmoid, greater palatine, sphenopalatine and superior labial arteries in the anteroinferior nasal septum (see article on Kiesselbach
'splexus)
Venous drainage
A rich venous submucosal venous network is formed by veins that accompany arteries. It should be noted that the posterior ethmoid veins anastomose with veins of the dura mater and orbit, making this a potential route of spread of infection. There is also an anastomosis with veins of the external nose 6.
Innervation
The olfactory nerve (CN I) supplies the special sensation of smell to the olfactory epithelium in the roof of the nasal cavity, with fibres passing upwards through the cribriform plate to the olfactory bulb.
Mucosal somatic sensation of the nasal cavity is derived from numerous nerves, but in general terms the branches of the ophthalmic division of the trigeminal nerve (CN Va) supply the anterosuperieranterosuperior half whereas branches of the maxillary division of the trigeminal nerve (CN Vb) supply the posteroinferior half. More specifically:
- the nasal septum is innervated by:
- anterior: anterior ethmoidal nerve
- posterosuperior: medial branch of the posterior superior nasal nerve
- posteroinferior: nasopalatine nerve
- the lateral nasal wall is innervated by:
- anterosuperior: anterior ethmoidal nerve
- anteroinferior: anterior superior alveolar nerve
- posterosuperior: lateral branch of the posterior superior nasal nerve
- posteroinferior: lateral posterior inferior nasal nerve from the greater palatine nerve
Lymphatic drainage
- anterior drainage: to the external nose 6
- posterior drainage: via separate pathways to the lateral pharyngeal lymph nodes or deep cervical chain 6
-<li>posteriorly: posterior nasal aperture (choanae) at the posteiror margin of the bony nasal spetum</li>-</ul><p>In the midline, the nasal cavity is divided into right and left halves by the nasal septum composed of fibrocartilage anteriorly and the <a href="/articles/vomer">vomer</a> and the perpendicular plate of the <a href="/articles/ethmoid-bone-1">ethmoid bone</a> posteriorly and inferiorly. </p><p>Anteriorly, it is continuous with the <a href="/articles/nose">nose</a> at the nasal aperture and posteriorly it is continuous with the <a href="/articles/nasopharynx">nasopharynx</a>. Laterally, the three nasal conchae form three <a href="/articles/nasal-meatus">nasal meatus</a>.</p><h5>Connections</h5><ul>- +<li>posteriorly: posterior nasal aperture (choanae) at the posterior margin of the bony nasal septum</li>
- +</ul><p>In the midline, the nasal cavity is divided into right and left halves by the <a title="Nasal septum" href="/articles/nasal-septum">nasal septum</a> composed of fibrocartilage anteriorly and the <a href="/articles/vomer">vomer</a> and the perpendicular plate of the <a href="/articles/ethmoid-bone-1">ethmoid bone</a> posteriorly and inferiorly. </p><p>Anteriorly, it is continuous with the <a href="/articles/nose">nose</a> at the nasal aperture and posteriorly it is continuous with the <a href="/articles/nasopharynx">nasopharynx</a>. Laterally, the three nasal conchae form the three <a href="/articles/nasal-meatus">nasal meati</a>.</p><h5>Connections</h5><ul>
-</ul><h4>Blood supply</h4><h5>Arterial supply</h5><p>The arterial supply of the nasal cavity is rich and derives from both the <a href="/articles/internal-carotid-artery-1">internal</a> and <a href="/articles/external-carotid-artery-1">external carotid arteries</a><sup> 4, 5</sup>:</p><ul>- +</ul><h4>Blood supply</h4><h5>Arterial supply</h5><p>The arterial supply of the nasal cavity is rich and derives from both the <a href="/articles/internal-carotid-artery-1">internal</a> and <a href="/articles/external-carotid-artery-1">external carotid arteries</a><sup> 4,5</sup>:</p><ul>
-<li>postero-inferiorly: sphenopalatine artery</li>-<li>superiorly: anterior and posterior ethmoid arteries</li>- +<li>posteroinferiorly: sphenopalatine artery</li>
- +<li>superiorly: anterior and posterior ethmoidal arteries</li>
-<strong>Kiesselbach plexus:</strong> anastomosis of the anterior ethmoid, greater palatine, sphenopalatine and superior labial arteries in the anteroinferior nasal septum (see article on <a href="/articles/kiesselbachs-plexus">Kiesselbach's plexus</a>)</li>-</ul><h5>Venous drainage</h5><p>A rich venous submucosal venous network is formed by veins that accompany arteries. It should be noted that the posterior ethmoid veins anastomose with veins of the dura mater and orbit, making this a potential route of spread of infection. There is also an anastomosis with veins of the external nose <sup>6</sup>.</p><h4>Innervation</h4><p>The <a href="/articles/olfactory-nerve">olfactory nerve (CN I)</a> supplies the special sensation of smell to the olfactory epithelium in the roof of the nasal cavity, with fibres passing upwards through the <a href="/articles/cribriform-plate">cribriform plate</a> to the <a href="/articles/olfactory-nerve">olfactory bulb</a>.</p><p>Mucosal somatic sensation of the nasal cavity is derived from numerous nerves, but in general terms the branches of the ophthalmic division of the <a href="/articles/trigeminal-nerve">trigeminal nerve</a> (CN Va) supply the anterosuperier half whereas branches of the maxillary division of the trigeminal nerve (CN Vb) supply the posteroinferior half. More specifically:</p><ul>- +<strong>Kiesselbach plexus:</strong> anastomosis of the anterior ethmoid, greater palatine, sphenopalatine and superior labial arteries in the anteroinferior nasal septum (see article on <a href="/articles/kiesselbachs-plexus">Kiesselbach plexus</a>)</li>
- +</ul><h5>Venous drainage</h5><p>A rich venous submucosal venous network is formed by veins that accompany arteries. It should be noted that the posterior ethmoid veins anastomose with veins of the dura mater and orbit, making this a potential route of spread of infection. There is also an anastomosis with veins of the external nose <sup>6</sup>.</p><h4>Innervation</h4><p>The <a href="/articles/olfactory-nerve">olfactory nerve (CN I)</a> supplies the special sensation of smell to the olfactory epithelium in the roof of the nasal cavity, with fibres passing upwards through the <a href="/articles/cribriform-plate">cribriform plate</a> to the <a href="/articles/olfactory-nerve">olfactory bulb</a>.</p><p>Mucosal somatic sensation of the nasal cavity is derived from numerous nerves, but in general terms the branches of the ophthalmic division of the <a href="/articles/trigeminal-nerve">trigeminal nerve</a> (CN Va) supply the anterosuperior half whereas branches of the maxillary division of the trigeminal nerve (CN Vb) supply the posteroinferior half. More specifically:</p><ul>