Upper airway and GIT

Question 1

Recall the functions of the nasal cavities

Answer 1

Warm and humidify air, help trap pathogens

Question 2

What lies on the lateral wall of each of the nasal cavities?

Answer 2

Nasal conchae

Question 3

What lies in between each nasal cavity?

Answer 3

Meatuses

Question 4

Recall the bones that contribute to each nasal concha

Answer 4

Superior and middle conchae = parts of ethmoid bone

Inferior concha = bone in itself

Question 5

Recall the 4 nerves innervating the nasal cavity, and what they are involved in sensing

Answer 5

1. Olfactory nerve - olfaction
2. Trigeminal nerve - sensory (V1 = anterior, V2 = posterior)
3. Facial nerve - glands
4. T1 SNS fibres = VSMCs

Question 6

Recall the blood supply to the nasal cavity and its clinical relevance

Answer 6

Ant. and post. ethmoidal arteries

Area of significant anastomoses is prone to nose bleeds

Question 7

Summarise the venous drainage of the nasal cavity

Answer 7

Nasal vein
Facial vein
Pterygoid plexus
Cavernous sinus

Question 8

Recall each of the paranasal sinuses

Answer 8

Frontal
Ethmoidal air cells
Sphenoid
Maxillary

Question 9

Recall the relative positioning of the paranasal sinuses in a lateral view

Answer 9

Anterior: Superior to inferior = frontal (eye sockets) maxillary
Posterior to eye sockets, working posteriorly = eye sockets, sphenoid`

Question 10

Recall the regional mapping of each nasal cavity, and summarise the function of each region

Answer 10

3 regions:

1. Nasal vestibule (particle removal)
2. Respiratory region (temo and humidity adjustment)
3. Olfactory region (olfaction)

Question 11

Describe the lining of each of the paranasal sinuses

Answer 11

Ciliated and mucous-secreting respiratory mucosa

Question 12

Describe the innervation of the paranasal sinuses

Answer 12

Branches of the trigeminal

Question 13

Why do the paranasal sinuses provide a possible route for infection?

Answer 13

Connected to pharynx by small holes

Question 14

Where do the posterior ethmoidal air cells drain into?

Answer 14

Superior nasal meatus

Question 15

Which paranasal sinus is the largest?

Answer 15

Maxillary

Question 16

How may the maxillary sinus in particular provide a route for infection?

Answer 16

Only a thin layer separating it from tooth so tooth infection can infect sinus

Question 17

What are the 2 functions of the larynx?

Answer 17

Voice box

Valve to close LRT

Question 18

Recall the structural components of the larynx

Answer 18

3 large unpaired cartilages (cricoid, thyroid and epiglottis)
3 small paired cartilages (arytenoid, cuneiform and corniculate)
Fibro-elastic membrane

Question 19

From where is the larynx superiorly suspended?

Answer 19

Hyoid

Question 20

Describe the shape of the thyroid cartilage

Answer 20

Right and left lamina are widely separated posteriorly but converge to join anteriorly

Question 21

Describe the shape and location of the arytenoid cartilages

Answer 21

Pyramidal

Postero-inferior to epiglottis

Question 22

Recall the attachments of the vocal folds

Answer 22

Anterior = thyroid cartilage
Posterior = arytenoid cartilages

Question 23

What and where are the false vocal folds?

Answer 23

Vestibular folds = above bioth sides of the true vocal folds

Question 24

What structures of the larynx must move to affect pitch?

Answer 24

Arytenoid cartilages and cricothyroid joint

Question 25

Recall the functional components of the facial nerve

Answer 25

Motor - to muscles of facial expression Sensory - contributes to lingual nerve via CT to supply ant. 2/3 of tongue PNS - salivary glands (not parotid) and lacrimal glands

Question 26

Recall the route of the facial nerve

Answer 26

Leaves skull via IAM Passes through stylomastoid foramen Supplies face via parotid gland

Question 27

Recall the pathophysiology of Bell's palsy

Answer 27

Inflammation of stylomastoid foramen puts pressure on CNVII --> ipsilateral facial paralysis

Question 28

What function is lost when there is a lesion of the internal laryngeal nerve?

Answer 28

Loss of sensation above vocal folds

Question 29

What function is lost when there is a lesion of the external laryngeal nerve?

Answer 29

Paralysis of cricothyroid

Question 30

What function is lost when there is a lesion of the recurrent laryngeal nerve

Answer 30

Paralysis of all muscles of larynx except cricothyroid | Loss of sensation BELOW vocal folds

Question 31

Summarise the cough and sneeze reflexes and how to differentiate them

Answer 31

Irritation sensed by laryngeal branches of CNX Phrenic and thoracic nerves initiate deep inhalation Closed glottis --> pressure buildup Forced exhalation Cough only: air escapes via mouth as oropharyngeal isthmus = open Sneeze only: air escapes via nose as oropharyngeal isthmus = closed

Question 32

What is the clinical relevance of the relationship between the mastoid antrum and the mastoid air cells

Answer 32

Infection can spread: pharynx --> middle ear --> mastoid process