The nasal cavity is the air-filled compartment above the palate, bordered by skeletal structures and cartilages, and covered from inside by mucosa. This page reviews the nasal cavity in a narrow osteology sense, i.e., as the cavity bordered by skeletal structures.
The frontal aspect of the skull demonstrating the anterior opening of the nasal cavity — the piriform aperture.
The list of terms:Apertura piriformis – Piriform aperture Incisura nasalis maxillae – Nasal notch of maxilla Processus frontalis maxillae – Frontal process of maxilla Os nasale – Nasal bone Spina nasalis anterior – Anterior nasal spine
The following two illustrations depicting the nasal cavity's lateral and medial walls are made by the sagittal cut of the skull passing through the left common nasal meatus.
The parasagittal cut of the skull, demonstrating the bones of the nasal septum relative to other walls of the nasal cavity. The perpendicular plate of ethmoid and vomer is the primary but not sole bony components of the nasal cavity's medial wall.
The list of terms:Septum nasi osseum – Bony nasal septum Os nasale – Nasal bone Spina nasalis ossis frontalis – Nasal spine of frontal bone Lamina perpendicularis ossis ethmoidalis – Perpendicular plate of ethmoid bone Rostrum sphenoidale – Sphenoidal rostrum Vomer Crista nasalis – Nasal crest Lamina cribrosa – Cribriform plate Sinus sphenoidalis – Sphenoid sinus Canalis incisivus – Incisive canal Spina nasalis anterior – Anterior nasal spine Spina nasalis posterior – Posterior nasal spine
She skull's parasagittal cut exposes the most structurally complex part of the nasal cavity—the lateral wall. The sphenoid sinus opens into the nasal cavity above the upper nasal concha — into the sphenoethmoid recess. And the pterygopalatine fossa communicates with the nasal cavity via the sphenopalatine foramen. The latter one localizes dorsally to the middle nasal concha.
The list of terms:Os ethmoidale – Ethmoid bone Concha nasalis superior – Superior nasal concha Concha nasalis media – Middle nasal concha Concha nasalis inferior – Inferior nasal concha Recessus sphenoethmoidalis – Sphenoethmoidal recess Apertura sinus sphenoidalis – Aperture of sphenoidal sinus Sinus sphenoidalis – Sphenoidal sinus Lamina cribrosa – Cribriform plate Os nasale – Nasal bone Facies nasalis maxillae – Nasal surface of maxilla Os lacrimale – Lacrimal bone Sinus maxillaris – Maxillary sinus Canalis incisivus – Incisive canal Processus palatinus maxillae – Palatine process of maxilla Lamina horizontalis ossis palatini – Horizontal plate of palatine bone Lamina perpendicularis ossis palatini – Perpendicular plate of palatine bone Lamina medialis processus pterygoidei – Medial pterygoid plate Foramen sphenopalatinum – Sphenopalatine foramen Sinus frontalis – Frontal sinus
The combined coronal and sagittal cut of the skull demonstrating the topography of ethmoid bone within the nasal cavity relative to the maxillary sinus and the nasal septum.
The list of terms:Septum nasi osseum – Bony nasal septum Sulcus vomeris Foramina cribrosa – Cribriform foramina Cellulae ethmoidales posteriores (labyrinthus ethmoidalis) – Posterior ethmoidal cells (ethmoidal labyrinth) Lamina orbitalis (papyracea) ossis ethmoidalis – Orbital plate (lamina papyracea) of ethmoid bone Concha nasalis media ossis ethmoidalis – Middle nasal concha of ethmoid Sinus maxillaris – Maxillary sinus Lamina perpendicularis ossis palatini – Perpendicular plate of the palatine bone Lamina horizontalis ossis palatini – Horizontal plate of palatine bone Processus palatinus maxillae – Palatine process of the maxilla Processus uncinatus ossis ethmoidalis – Uncinate process of ethmoid bone Sinus frontalis – Frontal sinus
Another combined cut of the skull, exposing the lateral wall of the nasal cavity—the wall where multiple compartments open in a tricky way:
Under the inferior nasal concha opens the nasolacrimal canal
Under the middle concha opens the maxillary sinus and, just above the ethmoidal bulla—the hiatus semilunaris. In its turn, the hiatus semilunaris communicates with the middle and anterior ethmoidal cells that directly connects to the frontal sinus.
Finally, under the upper concha opens the posterior ethmoid cells.
The list of terms:Lamina cribrosa – Bony nasal septum Bulla ethmoidalis Processus uncinatus ossis ethmoidalis – Uncinate process of ethmoid bone Sinus frontalis – Frontal sinus Processus frontalis maxillae – Frontal process of maxilla Os lacrimale – Lacrimal bone Processus lacrimalis conchae nasalis inferioris – Lacrimal process of inferior nasal concha Processus ethmoidalis conchae nasalis inferioris – Ethmoidal process of inferior nasal concha Os palatinum – Palatine bone Processus pterygoideus sphenoidalis – Pterygoid process of the sphenoid bone Septum nasi osseum – Bony nasal septum Sinus maxillaris – Maxillary sinus
The skull's coronal cut shows how nasal conchas split the airflow through the nasal cavity into the compartments: the upper, middle, and lower meatus in proximity to the nasal septum fuses into the one common nasal meatus.
The list of terms:Orbita – Orbit Sinus maxillaris – Maxillary sinus Labyrinthus ethmoidalis – Ethmoidal labyrinth Lamina cribrosa – Cribriform plate Cribrae ethmoidales – Cribriform foramena Palatum osseum – Bony (hard) palate Septum nasi osseum – Bony nasal septum Concha nasalis superior – Superior nasal concha Concha nasalis media – Middle nasal concha Concha nasalis inferior – Inferior nasal concha Meatus nasi superior – Superior nasal meatus Meatus nasi medius – Middle nasal meatus Meatus nasi inferior – Inferior nasal meatus Meatus nasi communis – Common nasal meatus Recessus sphenoethmoidalis – Sphenoethmoidal recess Apertura sinus sphenoidalis – Aperture of sphenoidal sinus
The clip demonstrates multiple sections of the skull done through the nasal cavity.
First published: Feb/2020
Last update: 17/Nov/2020