Pharynx Flashcards
What are the contents and parts of the pharynx?
Nasopharynx
Oropharynx
Laryngopharynx (Hypo)
Adenoids
Tonsils
Constrictor muscles
Blood/Nerve supply
What is the nasopharynx?
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
What are the contents of the nasopharynx?
Nasopharyngeal tonsil (adenoids) - Part of Waldeyer's ring
Eustachian tube orifice
What is the Oropharynx?
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
What are the contents of the oropharynx?
Palatine tonsils
Anterior and posterior tonsillar pillars
Tell me about the palatine tonsils?
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
Tell me about the tonsillar pillars?
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
Describe the blood supply of the palatine tonsils.
Tonsillar branch of facial artery (also lingual/ascending palatine/ascending pharyngeal)
Venous drainage pharyngeal plexus (also paratonsillar vein)
Describe the lymph drainage of the palatine tonsils
Lymphatics pierce superior constrictor muscle Pass to nodes along internal jugular vein Jugulodigastric node (angle of mandible)
What is the laryngopharynx?
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.
Name the muscles involved in the pharyngeal musculature.
Superior constrictor
Middle constrictor
Inferior constrictor
They overlap each other (in the back)
Open anteriorly (for different openings)
Attached posteriorly by median raphe
Explain the mechanism of swallowing.
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
Describe the pharyngeal blood supply.
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)
Describe the pharyngeal nerve supply.
Motor:
- Vagus (X)
- Glossopharyngeal (IX)
- Hypoglossal (XII)
- Facial (VII)
Sensory:
- Nasopharynx - Maxillary division of Trigeminal (CN V2)
- Oropharynx - Glossopharyngeal (IX)
- Hypopharynx - Hypoglossal (XII)
Match the level of the vertebrae to parts of the larynx/pharynx.
C1 - Hard palate C2 - Angle of mandible C3 - Hyoid bone C4/5 - Thyroid cartilage (upper & lower) C6 - Cricoid cartilage
