W3: Nose, sinuses and orbits Flashcards
What bone forms part of the nasal septum?
Vomer, Perpendicular Plate, Cartilage
What is the function of the nasal mucosa?
Describe the passage of air flowing through the nostrils
What is the purpose of the concha?
Increase the surface area not only of the mucosa but also for mucous - ability to capture foreign particles
What type of mucosa is the respiratory mucosa - how does this relate to function?
Describe what is happening in the right side of the nasal concha
Infection -> inflamed mucous membrane = blockage of opening
What muscle moves tear fluid from lateral to medial during the normal process of blinking?
Tear fluid is moved from Lateral to medial through the superior and inferior puncta by the Obicularis Occuli (during blinking)
Where does fluid from the lacrimal duct drain into?
Empties inferior to the inferior concha into the inferior meatus
Describe the distribution of the olfactory epithelium in the nasal cavity
List/name the paranasal sinus’
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.
What structures produce the change in tone of voice when sick/infection occurs
Paranasal sinus’ change the resonance of the voice when sick
The size and shape of the sinuses ____ from person to person
VARIES
Describe how the Frontal & Ethmoid sinus drain
Describe how the Sphenoid sinus drains
Frontal Sinus -> Hiatus semilunaris
When standing normally (hard palate is horizontal) most of the drainages travel posteriorly through the nasopharynx to be swallowed
What happens to the paranasal sinuses as we age? Describe the significance of this
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.
What is another name of the Mx sinus?
What is the capacity of the Mx sinus?
Describe the shape of the Mx sinus
- 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.
If infection occurs (cold)/inflammation in the Mx sinus, how does this implicate pain localisation?
- 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
Where does the spenoid sinus drain?
Superior to the superior concha
Describe where the ethmoid air cells drain into?
What is the implication of infection of ethmoid cells
Describe the innervation of the nasal cavity
- Olfactory nerve
- General sensation = Anterior ethmoid (Branches of V1) & Posterior superior and inferior lateral nasal nerves (Branches of V2)
Describe the autonomic innervation of the nasal cavity
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
Describe the blood supply to the nasal cavity and its significance
The ethmoidal arteries which branch off the facial artery and branches off the Mx artery coming from sphenopalatine
Supplies the fluids for secretions
People who suffer from blood noses regularly have most likely damaged which artery?
The ethmoidal arteries particularly in **Kiesselbach’s area **
Describe the walls of the orbit
Which 7 bones make up the orbit
