Anatomy and Physiology of the Throat Flashcards
Another name for the nasal cavity
Nasopharynx
Another name for the oral cavity
Oropharynx
Another name for the larynx
Hypopharynx
2 parts of the oral cavity
Oral vestibule
Oral cavity proper
What is the oral vestibule?
Between the lips and teeth
What are the boundaries of the oral cavity?
Lips to palatoglossal arch (anterior pillar)
Palate to floor of mouth / tongue
Buccal mucosa
What are the salivary glands?
Parotid
Submandibular
Sublingual
Another name for the parotid duct
Stenson’s duct
What does the parotid duct pierce?
Buccinator muscle
Where does the parotid duct usually open into the mouth?
Opposite the maxillary second molar
Another name for the submandibular duct
Whartons duct
What muscle does the submandibular duct lie superior to?
Digastric muscle
What are the lobes of the submandibular gland and what are they separated by?
Superficial and deep lobes
Mylohyoid muscle
What nerve supplies general somatic afferent innervation to the anterior 2/3rds of the tongue?
Lingual nerve
What is the lingual nerve a branch of?
Mandibular division of the trigeminal nerve
What are the two parts of the tongue?
Anterior 2/3rds
Posterior 1/3rd
What is the anterior 2/3rds of the tongue derived from?
1st branchial arch
What supplies taste to the anterior 2/3rds of the tongue?
Chorda tympani
What is the posterior 1/3rd of the tongue derived from?
3rd branchial arch
What nerve supplies the posterior 1/3rd of the tongue?
CN IX
How many taste buds does the tongue have?
2000 - 8000
What types of taste buds are found on the tongue?
Filliform papillae
Fungiform papillae
Folliate papillae
Circumvallate papillae
Features of filiform papillae
Most numerous
Do not contain taste buds
Features of fungiform papillae
Scattered throughout dorsum of the tongue
Where are circumvallate papillae found?
In a row just anterior to the sulcus terminalis
What is the sulcus terminalis?
V shaped groove that demarcates the junction of the oral and pharyngeal portions of the tongue base
What do the intrinsic muscles of the tongue do?
Alter shape
What do the extrinsic muscles of the tongue do?
Alter position
What are the extrinsic muscles of the tongue?
Genioglossus
Styloglossus
Hyoglossus
Palatoglossus
What is the nerve supply of the tongue?
Hypoglossal nerve supplies all except from palatoglossus
What is the nerve supply of the palatoglossus?
Pharyngeal plexus (CN IX - X)
Functions of the tongue
Taste
Mastication
Swallowing
Speech
Definition of mastication
Chewing
Function of the oral cavity
Taste Mastication Speech Digestion Swallowing
What is involved in the oral cavity for speech?
Tongue
Cheek
Lips
What is involved in the oral cavity for digestion?
Salivary enzymes
What is involved in the oral cavity for swallowing?
Tongue
Hard palate
Soft palate
What do the muscles of mastication act on?
TMJ
What are the muscles of mastication?
Lateral pterygoid
Medial pterygoid
Temporalis
Masseter
Nerve supply of the muscles of mastication
CN V3
What are the 3 phases of swallowing?
- Oral phase
- Pharyngeal
- Oesophageal
What happens during the oral phase of swallowing?
Tongue propels the food (bolus) into the pharynx
Triggering the swallowing reflex
What is the afferent nerve supply to the swallowing reflex?
CN V, IV, X
What is the efferent nerve supply to the swallowing reflex?
CN VII, X, XII
Where is the swallowing centre found?
Medulla
What happens during the pharyngeal phase of swallowing?
Soft palate pulled upwards
Epiglottis covers the larynx, vocal cord approximate, larynx moves upwards
Upper oesophageal sphincter (UOS) relaxes
Respiration reflex inhibited
What happens during the oesophageal phase of swallowing?
Once bolus passes UOS, the sphincter constricts
Bolus propelled downwards by peristaltic motion, reflex via myenteric plexus
What provides motor innervation to both layers of the tunica muscularis?
Auerbachs plexus / myenteric plexus
Boundaries of the oropharynx
Lower border of the soft palate to the upper margin of the epiglottis
Palatoglossal arch to posterior pharyngeal wall
Lateral; faucial pillars and palatine tonsils
What is the epithelium of the oropharynx?
Stratified, non keratinised squamous epithelium
Nerve supply to oropharynx
CN IX and X
What is the blood supply to the hypopharynx?
Superior thyroid artery
Lingual artery
Ascending pharyngeal artery
Nerve supply to hypopharynx
Pharyngeal plexus
Boundaries of the hypopharynx
Superior margin of epiglottis to the lower border of the cricoid cartilage
Continuous with oesophagus
Anterior wall; back of larynx
What are the 3 subsites of the hypopharynx?
Pyriform sinus
Post cricoid area
Posterior pharyngeal wall
Nerve supply to hypopharynx
Pharyngeal plexus - CN IX and X
Function of the larynx
Respiratory tract
Voice
Swallowing
What are the 3 parts of the larynx?
Supraglottis
Glottis
Subglottic
Where does the supraglottis extend from?
Superior tip of the epiglottis to the floor of the ventricular fold (junction of respiratory and squamous epithelium)
Where does the glottis extend from?
Begins superiorly at the true vocal fold and extends inferiorly to a horizontal plane 5mm inferiorly to the vocal cord
Where does the subglottis region extend from?
Begins 5mm below the free edge of the true vocal cord and proceeds to the inferior border of the cricoid cartilage
What are the 7 segments of cartilage of the larynx?
Cricoid cartilage
Thyroid cartilage
Epiglottis
Paired arytenoid cartilages (corniculate and cuneiform)
What are the extrinsic muscles of the larynx?
Infrahyoid
Suprahyoid
Thyrohyoid
Function of extrinsic muscles of the larynx
Move the entire laryngeal complex
Function of the intrinsic muscles of the larynx
Regulate movements of the vocal folds
Innervation of the larynx
Motor - CN X
- all instrinsic muscles - recurrent laryngeal nerve
- except cricothyroid (external laryngeal nerve)
Sensory
- supraglottic - internal laryngeal nerve
- glottic and subglottic - recurrent laryngeal nerve
What laryngeal nerve has a higher risk of injury during operative chest procedures and why?
Left recurrent laryngeal nerve
It has a longer course since it loops around the aortic arch instead of the right subclavian artery
What is the source of energy for speech?
Air flow
How does phonation of speech work?
Flow of air through different vocal cord position, tension, vibration and length
What does resonation of speech depend on?
Oral / nasal speech balance Depends on - nasopharynx - nasal cavity - oral cavity
How is articulation of speech produced?
Lips
Tongue
Jaw
What is prosody?
The rhythm, stress and intonation of speech
What is prosody of speech assosiated with?
Brocas area of the left frontal lobe
