Nasal/Oral Cavities Flashcards
Describe the boarders of the nasal cavity
skip lateral wall
Roof - Cribriform Plate (of Ethmoid Bone) & Frontal Bone
Floor - ant ¾ Palatine Process (of Maxilla) & post ¼ Horizontal Process(of Palatine)
Medial Wall - Nasal Septum
Lateral Wall - Look it up
Anterior Wall - Nasal Bone & cartilages
Posterior Wall - Sphenoid Bone
What composes the lateral wall of the nasal cavity?
[Anterior] Nasal Surface of Maxilla Lacrimal Bone Inferior Nasal Concha Ethmoid Bone (Mid/Sup Concha) Perpendicular Plate (of Palatine Bone) Medial Plate of pterygoid Process (of Sphenoid Bone) [Posterior]
What composes the nasal septum?
- Septal Cartilage
- Perpendicular Plate (of Ethmoid Bone)
- Vomer Bone
What connects the nasal cavity to the superior sagittal sinus?
An opening just anterior to the crista gala of the ethmoid bone is the foramen cecum, which houses the vein connecting the nasal cavity and the sup. sagittal sinus.
Explain the purpose of the nasal conchae.
- Divides the lateral wall into three meatuses (named for the concha above)
- Increases surface area of membranous lining of nasal cavity, which filters inhaled air, eliminates particles, and humidifies/warms inhaled air.
What part of the nasal cavity houses the cranial nerves responsible for olfaction?
The roof, superior lateral wall, and superior septum of the cavity houses the olfactory epithelium with CN I neurons
What is the common meatus?
The common meatus is the space between the conchae and septum.
Where does the sphenoid sinus drain?
The sphenoidoethmoidal recess is where the sphenoid sinus drains.
Where does the ethmoid air cells drain?
The posterior EAC drains directly into the superior meatus
The middle EAC drain onto the bulla ethmoidalis.
The anterior EAC drain into the hiatus semilunaris.
Where does the frontal sinus drain?
The frontal sinus drains into the superior part of hiatus semilunaris (middle meatus) via the frontal nasal duct
Where does the maxillary sinus drain?
The maxillary sinus drains into the inferior part of hiatus semilunaris (middle meatus) via an ostium
Where is the hiatus semilunaris located
Within the middle meatus, it is anterior to Bulla Ethmoidalis
and posterior to Uncinate Process (of Ethmoid Bone).
Where does the nasolacrimal duct drain?
The nasolacrimal duct drains from the surface of the eye to the inferior meatus.
How is gravity overcome in maxillary sinus drainage?
Cilia - push the drainage towards its superior opening
Bernoulli’s Principal - expelling air (blowing nose) creates low pressure in the common meatus and drains sinus.
