(12.1+2) Pharynx & Larynx Flashcards
(42 cards)
Describe how the Pharynx is subdivided.
- Nasopharynx: base of cranium - soft palate
- Oropharynx: soft palate - superior border of Epiglottis
- Laryngopharynx: superior border of Epiglottis - Inferior border of Cricoid cartilage (anteriorly) & C6 (posteriorly)
Describe how the epithelium of Nasopharynx adapt to its function?
Pseudostratified columnar ciliated + Goblet cells
- Goblet cells secrete mucus catching foreign materials
- Cilia trap and swipe the mucus down to oropharynx to be swallowed
Describe how the epithelium of Laryngopharynx adapt to its function.
Stratified squamous non-keratinised
- Against abrasion during swallowing
The pharyngeal muscles are seperated in two layers, name the muscles and describe their functions.
Outer circular
- Superior & Middle & Inferior Constrictors
- Inferior has two fibres, Thyropharyngeal (upper) & Cricopharyngeal (lower)
- Constrict to push food down
Inner longitudinal
- Stylopharyngeus & Palatopharyngeus & Salpingopharyngeus
- Contract to shorten & widen the pharynx
Describe the phases of swallowing.
1 Voluntary: Tongue pushes food back to oropharynx
2 Pharyngeal: Respiration inhibited + Epiglottis closes glottis + Upper Oesophageal Sphincter relaxed
3 Oesophageal: Peristalsis + Lower Oesophageal Sphincter relaxed
Describe the innervation to the pharynx.
Pharyngeal Plexus: Glossopharyngeal & Vagus & SNS fibres from Superior Cervical Ganglion
Sensory
- Maxillary (CN Vii) -> Nasopharynx
- Glossopharyngeal (CN IX) -> Oropharynx
- Vagus (CN X) -> Laryngopharynx
Motor
- Vagus (CN X) -> all Pharyngeal muscles except
- Glossopharyngeal (CN IX) -> Stylopharyngeus
What arteries supply the Pharynx?
Branches from External Carotid A:
- Ascending pharyngeal
- Lingual
- Facial
- Maxillary
Describe the venous drainages of the Pharynx.
Pharyngeal Venous Plexus -> Internal Jugular Vein
Describe the Lymphoid tissues in the Pharynx
Aggregate become tonsils, forming Tonsillar (Waldeyer’s) Ring at Nasopharynx
- Adenoid tonsil (superior part)
- Tubular tonsils x2
- Palatine tonsils x2
- Lingual tonsil
Recurrent infection may cause chronic enlargement of Adenoid tonsil, suggest some complications of this.
- Breathing difficulties
- Speaking difficulties
- Feeding difficulties
- Blockage of Eustachian tube -> Otits media
- Snoring / Sleep Apnoea
Where does the Palatine tonsils drain into? Where do they locate?
- Jugulo-digastric (Tonsillar) lymph nodes
- Angle of mandible
Suggest why may a Tonsillectomy of the Palatine tonsil be risky.
- Haemorrhage from Internal Jugular Vein
- Internal Carotid A & Glossopharyngeal N pass laterally to Palatine tonsils
A patient came with a viral infection, you found his uvula shifted to the left side. What happened?
- Quinsy = peritonsillar abscess, infection spread from the right Palatine tonsil
Suggest some common sites of where food is likely to be sucked.
- Vallecula = in Oropharynx, region of palatine tonsils
- Piriform fossa = in Laryngopharynx, between epiglottis & tongue
Name 5 important bony structures in the Larynx.
- Hyoid Bone
- Epiglottis
- Thyroid Cartilage
- Cricoid Cartilages
- Arytenoid x2
Describe the movement of Epiglottis.
Contraction of Suprahyoid & Longituidinal Pharyngeal muscles -> elevate Hyoid bone & Larynx -> Epiglottis become horizontal -> closes Glottis
Describe the shape and clinical importance of its bony marking of Thyroid cartilage.
- Laryngeal prominence marks C4
= Bifurcation of Common Carotid A, Carotid Body & Sinus locate
= superior border of larynx
Describe the shape and clinical importance of its bony marking of Cricoid cartilage.
- Signet ring shape
- Marks C6
= inferior border of Hyoid bone
= Junction of Pharynx & Oesophagus
= Junction of Larynx & Trachea
Describe the shape and function of Arytenoid cartilage.
- Pyramid shape
- Attachments for Vocal cords
Where are the vocal cords attached?
Arytenoid Cartilage
Where does the vocal ligament arise from?
Upper free border of the Cricovocal Ligament (Conus Elasticus)
What is the Glottis?
Vocal cords x2 + Rima Glottis
Draw and label a simple diagram showing:
- Epiglottis
- Arytenoid Cartilage
- True Vocal Folds
- False Vocal Folds (What’s another name?)
- Glottis
- Rima Glottis
- Aryepiglottic Folds
- Base of the tongue
http://imgarcade.com/1/intrinsic-muscles-of-the-larynx-superior-view/
False vocal fold = vestibular fold
When are the vocal cords adducted and which muscles are responsible for it? Which nerves innervate this action?
Adduction (closes Rima Glottis) during phonation
- Lateral Cricoarytenoid muscle, Recurrent Laryngeal N
- Cricothyroid muscle, Inferior Laryngeal N