L12..2 Pharynx and Soft Palate

Question 1

Where does the pharynx begin and end

Answer 1

• Begins at base of skull → lower border of cricoid cartilage (C6)

Question 2

3 different pharynx and the general function?

Answer 2

• Nasopharynx
• Oropharynx
• Laryngopharynx
  
  • Closes the POS aspect of nose mouth and larynx → allowing air to go down these areas

Question 3

Pharyngobasilar fascia

Answer 3

• Where Muscles are deficient SUP → able to see pharyngobasilar fascia

Question 4

Constrictor muscles of the pharynx: S/M/I constrictors

Answer 4

• SUP: Attaches along raphe on top of buccinator → Projects POS, meets the other constrcitor at midline
• MID: surface of hyoid bone → projects POS into midline, meet with other constrictor at raphe
• INF → Laminar of thyroid cartilage and cricoid cartilage → project POS, meet other constrictor at raphe
  
  • NS from branches of vagus above

Question 5

Constrictor muscles of the pharynx: Cricopharyngeus

Answer 5

• INF part of the INF constrictor muscles (hard to separate)
• NS from branches of vagus from below
• These constrictor muscles form a sling at the back of these cavities.
• Push food down oral cavity to oesophagus

Question 6

Internal layer of muscles

Answer 6

• Salpingopharyngeus
• Palatopharyngeus
• Stylopharyngeus

Muscles directed down → when contract → widens pharynx during swallowing

Question 7

Salpingopharyngeus

Answer 7

Nasopharyngeal tube (auditory tube) to mucular wall of pharynx

Question 8

Palatopharyngeus

Answer 8

Soft palate to pharynx

Question 9

Stylopharyngeus

Answer 9

Styloid to pharynx

Penetrates gap b//w SUP and INF constrictors

Question 10

Nasopharynx

Answer 10

• Pharyngeal tonsil (adenoids): If inflammed = difficulty breathing
• Opening of auditory tube below the tubal elevation (formed by cartilaginous auditory tube)
  
  • Opening of tube is important for equilisation of pressure
  • If there is a difference b/w pressure inside and out → tympanic membrane may rupture

Question 11

Salpingopharyngeus unblocking auditory tube

Answer 11

• Salpingopharyngeus attaches to the cartilaginous part of auditory tube
  
  • When it contracts → able to open up auditory tube
  • Allow pressure to escape and unblock ear

Question 12

Oropharynx

Answer 12

• Soft palate and Uvula hanging from the top
• POS 1/3 of tongue
  
  • Have lingual tonsills
• Palatoglossal and palatopharyngeal arch

Question 13

Vallecula

Answer 13

• Space b/w POS 1/3 of tongue and epiglottis → Vallecula
  
  • Food sits at vallecula before pushing epiglottis down and moves into oesophagus
  • Protects the largyngeal inlet (which leads into the airway)

Question 14

Laryngopharynx

Answer 14

• Mucous membrane over cricoid cartilage
• Aryepiglottis fold forms borders of laryngeal inlet
• Epiglottis does not form a perfect seal closing the laryngeal inlet
  
  • Larynx is also elevated and helps form a seal when swallowing
• Piriform recess
  
  • Fluid able to spill out and around laryngeal inlet through piriform recess

Question 15

Sensory NS of the pharynx

Answer 15

• All by glossopharyngeal N (CN9)
  
  • Forms the afferent arc of Gag reflex
    
    • Use gag reflex to test integrity of glossopharyngeal N
• Except:
  
  • Nasal cavity bits → by branches of trigeminal N
  • Some laryngopharynx → some by vagus N

Question 16

Motor NS of the pharynx

Answer 16

• All by vagus
• Except for: Stylopharyngeus
  
  • Which is by glossopharyngeal N (CN9)
• Vagus N forms the efferent arch of the gag reflex

Question 17

Soft palate

Answer 17

• Musculus uvulae
  
  • Attached to the hard palate by palatine aponeurosis
  • Seal off nasal cavity when coughing
  • Seal off oral cavity when chewing (allow breathing when chewing)
  • Helps produce suction → close off nasal cavity during sucking

Question 18

5 muscular support of the soft palate

Answer 18

• Palatoglossus & palatopharyngeus → depress uvula
• Tensor veli palatini: Attaches to LAT part of palatine aponeurosis
• Levator veli palatini
  
  • Both from side of soft palate from above → pulls soft palate up
• Musculus uvulae
• All innervated by pharyngeal branches of vagus; EXCEPT for tensor veli palatini (by Trigeminal)

Question 19

What are Fauces?

Answer 19

Space bound by palato arches

Question 20

Waldeyer’s ring

Answer 20

• Incomplete ring of lymphoid tissue that guards the pharynx
  
  • Adenoid + palatine + lingual + tubal tonsils
• A first line defence → more important in children

Question 21

3 phases of the swallowing reflex

Answer 21

1. Bolus shaped and pushed by tongue to palate.
2. Soft palate descends and palatal arches are approximated to grip and push the bolus into the oropharynx.
3. Soft palate elevated and tightened to prevent bolus entering nasal cavity.
4. Larynx and pharynx elevated to bring bolus closer to oesophagus.
5. Laryngeal inlet closed to prevent bolus from entering the trachea.
6. Bolus is pushed down the oropharynx and over the epiglottis.
7. Bolus forced down through laryngopharynx and into oesophagus.
8. Larynx depressed to return to normal position (mainly by elastic recoil).