W3: Nose, sinuses and orbits

Question 1

What bone forms part of the nasal septum?

Answer 1

Vomer, Perpendicular Plate, Cartilage

Question 2

What is the function of the nasal mucosa?

Answer 2

+ humidifying air and immune function

Question 3

Describe the passage of air flowing through the nostrils

Answer 3

Question 4

What is the purpose of the concha?

Answer 4

Increase the surface area not only of the mucosa but also for mucous - ability to capture foreign particles

Question 5

What type of mucosa is the respiratory mucosa - how does this relate to function?

Answer 5

Question 6

Describe what is happening in the right side of the nasal concha

Answer 6

Infection -> inflamed mucous membrane = blockage of opening

Question 7

What muscle moves tear fluid from lateral to medial during the normal process of blinking?

Answer 7

Tear fluid is moved from Lateral to medial through the superior and inferior puncta by the Obicularis Occuli (during blinking)

Question 8

Where does fluid from the lacrimal duct drain into?

Answer 8

Empties inferior to the inferior concha into the inferior meatus

Question 9

Describe the distribution of the olfactory epithelium in the nasal cavity

Answer 9

Question 10

List/name the paranasal sinus’

Answer 10

Paranasal sinuses are air-filled extensions of the respiratory part of the nasal cavities. You may think of them as extensions into several of the surrounding bones.

They take their name from the bone in which they are located

Question 11

What structures produce the change in tone of voice when sick/infection occurs

Answer 11

Paranasal sinus’ change the resonance of the voice when sick

Question 12

The size and shape of the sinuses ____ from person to person

Answer 12

VARIES

Question 13

Describe how the Frontal & Ethmoid sinus drain
Describe how the Sphenoid sinus drains

Answer 13

Frontal Sinus -> Hiatus semilunaris

When standing normally (hard palate is horizontal) most of the drainages travel posteriorly through the nasopharynx to be swallowed

Question 14

What happens to the paranasal sinuses as we age? Describe the significance of this

Answer 14

As we age the sinuses extend becoming larger and changing shape until old age

This is enhanced by the loss of the alveolar bone in the maxilla.

Significance:
* roots of the posterior maxillar teeth may protrude into the maxillary sinus and implicate treatment plans - Potential problem for extraction of these posterior teeth.

Question 15

What is another name of the Mx sinus?
What is the capacity of the Mx sinus?
Describe the shape of the Mx sinus

Answer 15

• Sometimes called Antrum
• Largest sinus - average capacity of 15ml
• Approximates a 4 sided pyramid: 25mm side to side, 30mm A-P and 30mm
  high. Floor of sinus cavity extends onto the the uppermost part of the maxillary alveolar processes.

Question 16

If infection occurs (cold)/inflammation in the Mx sinus, how does this implicate pain localisation?

Answer 16

• Posterior superior alveolar nerve and middle superior alveolar nerve travel along the floor/wall of the Mx sinus just under the mucosa.
  = skewed interpretation of pain to be in teeth not sinus…ie. Pain caused by maxillary sinusitis is often mistaken as pain originating from one (or more) of the molars (and sometimes premolars) on that side.
  OR
  = Infection in the root can spread to the sinus and vice versa

Question 17

Where does the spenoid sinus drain?

Answer 17

Superior to the superior concha

Question 18

Describe where the ethmoid air cells drain into?

Answer 18

Question 19

What is the implication of infection of ethmoid cells

Answer 19

Question 20

Describe the innervation of the nasal cavity

Answer 20

• Olfactory nerve
• General sensation = Anterior ethmoid (Branches of V1) & Posterior superior and inferior lateral nasal nerves (Branches of V2)

Question 21

Describe the autonomic innervation of the nasal cavity

Answer 21

Secretomotor coming from parasympathetics
Pterygopalatine ganglion -> lacrimal -> nasal mucosa
= lots of mucous and serous secretion

Note: sudafed mimic’s sympathetic N.T = vasoconstriction and decrease in secretion

Question 22

Describe the blood supply to the nasal cavity and its significance

Answer 22

The ethmoidal arteries which branch off the facial artery and branches off the Mx artery coming from sphenopalatine
Supplies the fluids for secretions

Question 23

People who suffer from blood noses regularly have most likely damaged which artery?

Answer 23

The ethmoidal arteries particularly in **Kiesselbach’s area **

Question 24

Describe the walls of the orbit

Which 7 bones make up the orbit

Answer 24