Week 10.1 - The pharynx Flashcards
Describe the location of the nasopharynx. State its boudaries
- In line with C1
- From the back of the nose to the soft palate
- Superior = base of skull
- Inferior = level of soft palate
- Anterior = posterior choanae
- Posterior =nasopharyngeal tonsil (adenoid) and C1
Describe the location of the oropharynx. State its boundaries
- In line with C2 and C3
- From the soft palate to superior epiglottis
- Superior = level of the soft palate
- Inferior = supeior edge of epiglottis
- Anterior = oral cavity
- Posterior = c2/3
Describe the location of the laryngopharynx. State its boundaries
- From the superior border of epiglottis to the opening if the oesophagus/trachea
- In line with C4,5 and 6
- Superior = Superior ridge of epiglottis
- Inferior = level of inferior cricoid cartilage
- Anterior = larynx
- Posterior = c3-c6
In which part of the pharynx does the palatine tonsil lie?
-oropharynx
What lines the nasopharynx?
-Respiratory ciliated pseudostratified epithelium and stratified squamous
What structures lie in the nasopharynx?
- Adenoids
- Eustachian tube orifice
What is the palatoglossal arch?
- The anterior arch in the oral cavity
- Marks the boundary between the oral cavity an the oropharynx
What is the palatopharyngeal arch?
-Posterior arch in the oral cavity
Describe the palatine tonsil
-An encapsulated area of lymphoid tissue covered in squamous epithelium
When do the palatine tonsils begin to atrophy?
-After puberty
What makes the floor of the tonsillar fossa?
-Superior constrictor muscle
Describe the blood supply to the palatine tonsils
- Tonsillar branch of facial artery (aso lingual and ascending pharyngeal/palatine)
- Venous is pharyngeal plexus (and also paratonsilar vein)
Describe the lymphatic drainage of the palatine tonsils
-Lymphatics pierce superior constrictor muscle and pass to nodes along the internal jugular vein, specifically jugulodigastric
What tonsils create waldeyers ring?
-Palatine, adenoid (nasopharyngeal), lingual, tubal
Which nodes do the adenoids drain to?
-deep cervical and retropharyngeal
What are the constrictor muscles of the pharynx?
- Superior, middle and inferior muscles which overlap one another. They are open at the front (attach laterally to trachea) and attach posteriorly at the median raphe
- Contract sequentially to move food bolus down the oesophagus
Describe the innervation of the pharyngeal constrictors
-Superior laryngeal nerve
Describe the process of swallowing
- Oral phase -> Tongue elevates pushing food bolus to back of mouth. Soft palate elevates and seals off nasopharynx. Tongue and suprahyoid muscles pull up larynx
- Pharyngeal phase ->Epiglottis changes shape to block trachea. Piriform fossa funnels food into laryngopharynx and sequential contraction of the constrictors and relaxation of cricopharyngeus
- Oesophageal phase -> peristaltic contration of oesophagus
Describe the blood supply to the pharynx
-Tonsillar branch of facial artery
-Ascending pharyngeal
-Ascending palatine
(all from ECA)
Describe the venous drainage of the pharynx
-Pharyngeal plexus
IJV
Describe the motor supply to the pharynx
- Vagus (constrictors and palatopharyngeus, salpingopharyngeus)
- Glossopharyngeal (stylopharyngeus)
Describe the sensory supply to the pharynx
- Nasopharynx -> CNV2
- Oropharynx -> CNIX
- Hypopharynx -> CNX
State what bony/cartilage features can be found at the vertebral levels of C1,2,3,4,5,6
- C1 -> hard palate
- C2-> angle of mandible
- C3 -> hyoid bone
- C4/5 -> Thyroid cartilage
- C6 -> Cricoid cartilage
Under what do the left and right RLNs pass?
- Left = arch of aorta
- Right = right subclavian
What is the most common cause of adenoid enlargement?
-Viral/bacterial infection
After what age do the adenoids begin to regress?
-8 years
State the common consequencesNasalof adenoid enlargement
- Eustachian tube obstruction (acute otitis media with effusion)
- Nasal obstruction
- Obstructive sleep apnoea
Where does posterior herniation of pharyngeal mucosa most commonly occur? (pharyngeal diverticulum)
Why does it occur?
- Killian’s dehiscence (inferior constrictor and cricopharyngeus)
- Weaker area
- Incoordination of swallowing
- Cricopharyngeal spasm