Pharynx

Question 1

What are the contents and parts of the pharynx?

Answer 1

Nasopharynx
Oropharynx
Laryngopharynx (Hypo)

Adenoids
Tonsils
Constrictor muscles
Blood/Nerve supply

Question 2

What is the nasopharynx?

Answer 2

The top portion of the pharynx
Above soft palate

Boundaries:

• Superior - Skull base
• Inferior - Level of soft palate
• Anterior - Posterior Choanae (posterior nasal apertures)
• Posterior - Nasopharyngeal tonsil, C1

Lined with respiratory ciliated stratified squamous epithelium

Question 3

What are the contents of the nasopharynx?

Answer 3

Nasopharyngeal tonsil (adenoids)
- Part of Waldeyer's ring

Eustachian tube orifice

Question 4

What is the Oropharynx?

Answer 4

Behind oral cavity & tongue

Boundaries:

• Superior - Level of soft palate
• Inferior - Superior edge of epiglottis
• Anterior - Oral cavity
• Posterior - C2 - C3

Lined with stratified squamous epithelium

Question 5

What are the contents of the oropharynx?

Answer 5

Palatine tonsils

Anterior and posterior tonsillar pillars

Question 6

Tell me about the palatine tonsils?

Answer 6

Lie in tonsillar fossae (between anterior and posterior pillars)

Tonsil encapsulated
Tonsillar fossa floor - superior constrictor muscle
Lymphoid tissue covered with squamous epithelium
Atrophies after puberty

Question 7

Tell me about the tonsillar pillars?

Answer 7

Anterior pillar (palatoglossal arch)

• Boundary between buccal cavity and oropharynx
• Fuses with lateral wall of tongue
• Contains palatoglossal muscle

Posterior pillar (palatopharyngeal arch)

• Blends with wall of pharynx
• Contains palatophayngeus muscle

Question 8

Describe the blood supply of the palatine tonsils.

Answer 8

Tonsillar branch of facial artery (also lingual/ascending palatine/ascending pharyngeal)
Venous drainage pharyngeal plexus (also paratonsillar vein)

Question 9

Describe the lymph drainage of the palatine tonsils

Answer 9

Lymphatics pierce superior constrictor muscle
Pass to nodes along internal jugular vein
Jugulodigastric node (angle of mandible)

Question 10

What is the laryngopharynx?

Answer 10

The last part of the pharynx
Also known as hpopharynx
Below epiglottis

Boundaries:

• Superior - Superior edge of epiglottis
• Inferior - level of inferior edge of cricoid cartilage
• Anterior - larynx
• Posterior - C3 - C6 vertebrae

Inferiorly opens into oesophagus (post) and larynx (ant)
Lined with stratified squamous epithelium.

Question 11

Name the muscles involved in the pharyngeal musculature.

Answer 11

Superior constrictor
Middle constrictor
Inferior constrictor

They overlap each other (in the back)
Open anteriorly (for different openings)
Attached posteriorly by median raphe

Question 12

Explain the mechanism of swallowing.

Answer 12

Pushing food from oral cavity to oropharynx
- Tongue and suprahyoid muscles pull hyoid and larynx
up
- Soft palate elevates - nasopharynx closed off
- Superior constrictors contract

Food bolus passes into hypopharynx by aid of middle and inferior constrictors

Larynx protected by - overhanging tongue, epiglottis, vocal cords
Cricopharyngeus relaxes

Question 13

Describe the pharyngeal blood supply.

Answer 13

Arterial:

• Superior thyroid artery
• Ascending pharyngeal artery
• Ascending and descending palatine artery
• Branches of lingual, facial and maxillary arteries
• (External carotid artery)

Venous:

• Pharyngeal venous plexus
• (Internal Jugular Vein)

Question 14

Describe the pharyngeal nerve supply.

Answer 14

Motor:

• Vagus (X)
• Glossopharyngeal (IX)
• Hypoglossal (XII)
• Facial (VII)

Sensory:

• Nasopharynx - Maxillary division of Trigeminal (CN V2)
• Oropharynx - Glossopharyngeal (IX)
• Hypopharynx - Hypoglossal (XII)

Question 15

Match the level of the vertebrae to parts of the larynx/pharynx.

Answer 15

C1 - Hard palate
C2 - Angle of mandible
C3 - Hyoid bone
C4/5 - Thyroid cartilage (upper & lower)
C6 - Cricoid cartilage