Lecture 10: Pharynx and Larynx Flashcards
Divisions of the pharynx?
Is formed by muscles and fascia and extends from the base of the skull to the upper boarder of the esophagus at C6.
divided into the nasopharynx, oropharynx and laryngopharynx
Major muscle groups forming the pharynx?
Constrictor muscles - superior beneath the middle beneath the inferior (all without an anterior part or inferior part - can be divided into left and right part joining at the back of the parynx) - Innervated by the VAGUS (CN X)
Longitudinal muscles - attach to the base of the skull running between/inside the costrictor muscles to hold them. - stylopharyngeus IX (from styloid process), palatopharyngeus X (from the palate) and salpingopharyngeus X (from pharyngotympanic tube to the pharynx)
Pharygobasilar fascia sits deep to the mucosa but ontop of muscle and aids to stabilise
Constrictor muscle attachment?
Superior
- medial pterygoid plate of the sphenoid bone
- pterygoid hamulus
- pterygomandibular raphae
- mandible
Middle
- stylohyoid ligament
- styloid process of temporal bone
- lesser and greater horn of hyoid
Inferior
- superior tuburcle then oblique line to inferior tuburcle of thyroid cartilage.
- fascia of cricothyroid muscle
- cricoid cartilage
Gaps in the constrictor muscle
Between the superior and middle constrictor runs the lingual artery as well as CN XII and IX as well as the lingual nerve = oropharyngeal triangle
Between the middle and inferior constrictor muscles runs the internal laryngeal nerve and vessels
Below the inferior constrictor comes up the recurrent laryngeal nerve inferior laryngeal vessels
Mucosal features of the pharynx?
Nasopharynx
- has the pharyngeal tonsil that can become inflamed and block blocking the nasal cavity stopping breathing
- opening of the pharyngotympanic tube for regulation of presssure
Oropharynx
- palatine tonsil
- lingual tonsil - most posterior part of tongue
Adenoids are enlarged pharyngeal tosils at the base of the skull
Blood supply to the pharynx?
Upper part
- branches of the external carotid (lingual, maxillary, facial, ascending pharyngeal
lower part
- branches of the subclavian (inferior thyroid artery of the thyrocervical trunk)
NB: palatine tonsil supplied by the tonsilar branch of the facial artery
Innervation of the pharynx?
Nasopharynx - sensory supplied by V2
Oropharynx - sensory supplied by CN IX
Laryngopharynx - sensory supplied by CN X
CN IX and X form the pharyngeal plexus for motor information
Laryngeal cartilage structures?
Laryngeal prominance = adam’s apple
Thryoid cartilage has superior thryoid tuburcle connected to inferior via the oblique line - attachement for inferior constrictor muscle.
uneiform cartilage sit within fascia not floating
Extrinsic ligaments of the thyrohyoid region?
The thryohoid membrane connects the two and has an apeture for the internal branch of superior laryngeal nerve associated artery (originates from the superior thyroid artery)
Intrinsic ligaments?
The cricothryoid ligament runs between the cricoid cartilage and the thyroid cartilage. It is thick at the upper boarder and this is the vocal ligament
The quadriangular membrane runs between epiglottis the thyroid cartilage and the arytenoid cartilage the has a thickening called the vestibular ligament that is a false vocal ligament.
Clinically important space in the cavity of the larynx?
The piriform recess sits lateral to the ary-epiglottic fold that is formed by the ary-epiglottic ligament running from the arytenoid cartilage to the lateral epiglottis -
things get stuck here all the time as an adult bu tthey are necessary as a kid for being able to eat/drink
Intrinsic muscles?
Cricothyroid - straight and oblique parts
Vocalis muscle runs parallel to the vocal ligaments are aids in talking. The Posterior crico-arytenoid muscle is the only muscle the adbucts the ligaments (opens the airways) and is innervated by the recurrent laryngeal nerve**
Blood supply to the larynx?
Mostly superior laryngeal artery from the superior thyroid artery from the external carotid (importance of ligating the thyroid artery after the superior laryngeal has branched) - above the vocal cords
Also the inferior laryngeal from the inferior thyroid off the subclavian artery for all supply below the vocal cords.
Venous drainage and lymhatics?
Innervation?
Superior laryngeal and inferior laryngeal vein off the superior and inferior thyroid vein
Superior laryngeal nerve - gives off the internal laryngeal nerve supplies sensory above the vocal cords.
The recurrent laryngeal supplies the sensory below the vocal cords.
All muscles of the larynx are innervated by the VAGUS - recurrent laryngeal nerve (except one unimportant one)
