Nose: Nasal Cavity Flashcards
Nasal cavity
2 cavities separated by nasal septum
Boundries
Each cavity opens
1. Anterior:
on face by anterior nasal aperture (nostril or anterior nares)
2. Posterior:
in nasopharynx by posterior nasal aperture (choana)
Roof
- Anterior sloping part
- Middle horizontal part
- Posterior sloping part
Anterior sloping part
Nasal and frontal bones
Middle horizontal part
Cribriform plate ethmoid
Posterior sloping part
Sphenoid body
Floor
Hard palate
Palatine process of maxilla anterior and horizontal plate of palatine bone posterior with incisive fossa and canals 2 cm behind its anterior end
Medial wall
Nasal septum
1. In front: septal cartilage
2. Below and behind: vomer
3. Above and behind: perpendicular plate ethmoid
4. Small posterior part: sphenoid rostrum
Lateral wall
Bones forming:
1. Below and in front: medial surface maxilla
2. Behind maxilla: perpendicular plate of palatine bone
3. Most posterior part: medial pterygoid plate
4. Upper part: medial surface of ethmoidal labyrinth
5. Upper anterior part: nasal frontal process of maxilla and lacrimal bones
Parts (3)
- Vestibule
- Atrium of middle meatus
- Nasal conchae and meatuses
Vestibule part
Small dilated part above nostril lined by skin containing:
1. Sweat glands
2. Sebaceous glands
3. Coarse hairs for filtration of dust
Atrium of middle meatus
Shallow depression above and behind vestibule continuous posterior with middle meatus
Nasal conchae
Lateral wall shows 3 bony projections with highly vascular mucosa:
1. Superior
2. Middle
3. Inferior
Superior concha
Smallest
Project from ethmoidal labyrinth
Middle concha
Largest
Project from ethmoidal labyrinth
Inferior concha
Largest
Separate skull bone
Conchae functions
- Increase surface area which magnifies air turbelance improving olfaction
- Increase humidity
- Warming of inspired air
Nasal meatus
Space below each conchae