Pharynx and Cervical Oesophagus Flashcards
What is the Pharynx?
- Superior expanded part of the oesophagus posterior to the nasal and oral cavities
Pharynx
* Extent:
o Superior-
o Inferior-
o Anterior-
o Posterior-
o Superior- cranial base
o Inferior- inferior border of cricoid cartilage at the level of C6 vertebra
o Anterior- nasal cavity, oral cavity and larynx
o Posterior- buccopharyngeal fascia
Pharynx:
* Widest opposite hyoid (5 cm) and narrowest at junction with oesophagus (1.5 cm)
* flat posterior wall lies against the prevertebral layer of deep cervical fascia
* divided into 3 parts:
o Nasopharynx- posterior to the nose and superior to the soft palate
o Oropharynx- posterior to mouth
o Laryngopharynx- posterior to the larynx
What is the Nasopharynx? (2)
- Has a respiratory function
- Posterior extension of the nasal cavities
Nasopharynx:
- Borders:
o Anterior-
o Posterior-
o Roof-
o Anterior- choana and soft palate
o Posterior- basilar part of the occipital bone and C1 vertebra
o Roof- body of sphenoid
Nasopharynx:
o Tonsils (aggregates of lymphoid tissue): (2)
- Pharyngeal (adenoid) tonsil- in the mucosa of the roof and posterior wall of the nasopharynx
- Tubal tonsils- in the submucosa of the pharynx near the nasopharyngeal opening
Nasopharynx:
o Opening of the _________ tube
pharyngotympanic
Nasopharynx:
o Salpingopharyngeal fold: (3)
- Extends inferiorly from the medial end of the pharyngotympanic tube
- Vertical fold of the mucosa
- Covers the salpingopharyngeus muscle
Nasopharynx:
o Torus tubarius:
- Superior to the opening of the pharyngotympanic tube
Nasopharynx:
o Pharyngeal recess: (2)
- Posterior to the torus tubarius and salpingopharyngeal fold
- Extends laterally and posteriorly
What is the function of the Oropharynx?
- Has a digestive function
Oropharynx:
Boundaries:
o Superior-
o Inferior-
o Lateral-
o Posterior-
o Superior- soft palate and uvula
o Inferior- base of the tongue and superior border of epiglottis
o Lateral- palatopharyngeal and palatoglossal arches
o Posterior- pharyngobasilar fascia over palatopharyngeus, superior constrictor and body of C2
Oropharynx:
Contents: (3)
o Palatine tonsils
- On each side of the oropharynx in the tonsillar bed between the palatine arches
(palatopharyngeal and palatoglossal arches)
o Tonsillar bed
- Formed by the superior pharyngeal constrictor and the thin, fibrous sheet of pharyngobasilarnfascia
* Fascia blends with the periosteum of the cranial base
o Lingual tonsils
- On the posterior third of the tongue
What does Pharyngeal lymphatic (Waldeyer’s) ring consist of? (5)
1 pharyngeal tonsil
2 tubal tonsils
2 palatine tonsils
1 lingual tonsil
2 lateral bands
Where does the Laryngopharynx lie?
- Lies posterior to the larynx
Laryngopharynx
* Boundaries:
o Superior-
o Inferior-
o Anterior-
o Posterior-
o Lateral-
o Superior- superior border of the epiglottis and pharyngoepiglottic folds
o Inferior- inferior border of the cricoid cartilage
o Anterior- larynx
o Posterior- pharyngobasilar fascia, middle and inferior constrictor muscles and C4- C6 vertebrae
o Lateral- pharyngobasilar fascia and middle and inferior constrictor muscles
Laryngopharynx:
Features: (3)
o Laryngeal inlet
o Piriform fossa (recess)
o Aryepiglottic fold
Laryngopharynx:
o Laryngeal inlet:
- Communication between the laryngopharynx and the larynx on the anterior wall
Laryngopharynx:
o Piriform fossa (recess): (3)
- Small depression of the laryngopharyngeal cavity on either side of the laryngeal inlet
- Laterally bounded by the medial surfaces of the thyroid cartilage and the thyroid membrane
- Branches of the internal and recurrent laryngeal nerves lie deep to its mucosa
- Vulnerable to injury when a foreign body lodges in the fossa
Laryngopharynx:
o Aryepiglottic fold:
- Separates the piriform fossa from the laryngeal inlet
What are the features of the Pharyngeal muscles? (3)
- Arranged with longitudinal muscles internally and circular muscles externally
- Circular muscles are the pharyngeal constrictors
- Internal longitudinal muscles elevate the larynx and shorten the pharynx during swallowing/speaking
Pharyngeal muscles:
* Fascial lining: (2)
o Strong internal pharyngobasilar fascia
o Thin external buccopharyngeal fascia (blends with the pretracheal layer of deep cervical fascia)
* Constrictors contract involuntarily for sequential contraction
What are the External layer- pharyngeal constrictors?
Pharyngeal constrictors:
Superior:
Origin:
Insertion:
Innervation:
Main Action:
- Pterygoid hamulus
- Pterygomandibular raphe
- Adjacent part of mandible
Pharyngeal tubercle on basilar part of occipital bone
- Pharyngeal br. of vagus n.
- pharyngeal plexus
Constrict walls of pharynx during swallowing
