Nasal Cavity and Paranasal cavity

Question 1

General features of nasal cavity

Answer 1

a. Nose is most proximal portion of resp tract; composed of external bony and cartilaginous nose and internal nasal cavities. Fxns to warm, humidify, and filter
b. Paranasal sinuses are air-filled, epithelial lined spaces inside frontal, sphenoid, ethmoidal, and maxillary bones; act to lighten skull
c. The paranasal sinuses form post-natally as the epithelial-lines spaces excavate through surrounding bone

Question 2

Maxillary sinus

Answer 2

a. Within maxilla bone; largest of all air sinuses
1. superior - orbit
2. medial - nasal cavitu
3. inferior - maxillary teeth
4. anterior and lateral - cheek
5. posterior - pterygopalatine fossa
b. Drains to semilunar hiatus within middle nasal meatus
c. Innervated by branches of V2

Question 3

Frontal sinus

Answer 3

a. Within frontal bone, superior to superciliary arches, nasal bones
1. superior/posterior - cranial cavity
2. inferior - nasal cavity/orbit
b. Opens via frontonasal duct to semilunar hiatus within middle nasal meatus
c. Innervated by V1

Question 4

Sphenoidal sinus

Answer 4

a. Within body of sphenoid bone
1. superior - cranial cavity
2. lateral - cavernous sinus/cranial cavity
3. anterior/inferior - nasopharynx/nasal cavity
b. Open to shenoethmoidal recess
c. Innervated by V2

Question 5

Ethmoidal sinus

Answer 5

a. Within ethmoidal bone
b. Anterior, middle, and posterior air cells
1. superior - cranial cavity
2. middle/inferior - nasal cavity
3. lateral - orbit
c. Opens via:
1. semilunar hiatus of middle nasal meatus (anterior air cells)
2. ethmoidal bulla (middle air cells)
3. superior nasal meatus (posterior air cells)
d. Innervated by V1