Pharynx and Larynx Flashcards
The pharynx opens into the
Esophagus
Extent of pharynx
base of skull to level of C6 vertebra (lower border of cricoid cartilage)
Pharynx subdivisions
nasopharynx
oropharynx
laryngopharynx
Extents of pharynx subdivisions
Nasopharynx (from base of skull to soft palate)
Oropharynx (from soft palate to tip of epiglottis)
Laryngopharynx (from tip of epiglottis to lower border of cricoid level of C6 vertebra)
Communications of nasopharynx
Anterior: communicates with nasal cavity via nasal choanae
Inferior: communicates with oropharynx via pharyngeal isthmus
Laterally: communicates with middle ear via auditory tube (at tubal orifice)
The pharyngotympanic tube is the
Eustachian tube
Boundaries of tubal orifice
tubal elevation superiorly and posteriorly
Location of tubal tonsil
in the tubal orifice
Structure containing salpingopharyngeus muscle
salpingopharyngeal fold
Which fold holds the levator palatini muscle?
Salpingopalatine fold
Features of nasopharynx
Salpingopharyngeal and Palatopharyngeal folds
Tubal orifice
Tubal tonsil
Pharyngeal tonsils at junction of its superior and posterior wall
Communications of oropharynx
Anteriorly: with oral cavity via oropharyngeal isthmus
Superiorly: with nasopharynx through pharyngeal isthmus
Inferiorly: with laryngopharynx
Boundaries of tonsillar fossa. State which part of oropharynx it is found and its contents.
Anteriorly: Palatoglossal fold
Posteriorly: Palatopharyngeal fold
contains palatine tonsil
located on lateral wall of oropharynx
Communications of laryngopharynx
Anteriorly: larynx via laryngeal inlet
Inferiorly: with esophagus
Superiorly: with oropharynx
Location of piriform fossa
Lateral wall of laryngopharynx
Boundaries of piriform fossa
Superomedial: aryepiglottic fold
Laterally: Thyroid cartilage + mucous membrane covering thyrohyoid membrane
Clinical signifiance of piriform fossa.
Internal laryngeal nerve (together with superior laryngeal vessels) travel across its floor from lateral to medial. When food gets impacted and attempts to remove it cause damage to the internal laryngeal nerve, there is loss of cough reflex due to sensory loss
Name layers of pharyngeal wall from inside out
*MNEMONIC: Medical Students Pay Millions of Bucks!
Mucosa Submucosa Pharyngobasillar fascia Muscularis (inner longitudinal outer circular) Buccopharyngeal fascia
The only external muscle of pharynx that does not get supply from vago-accessory pharyngeal plexus complex is the
Stylopharyngeus which gets Glossopharyngeal nerve
Describe sensory innervation to subdivisions of pharynx
Pterygopalatine ganglion pharyngeal branch –> nasopharynx
Glossopharyngeal nerve –> oropharynx
Internal laryngeal nerve –> laryngopharynx
*MNEMONIC: Please Give In love!
Name structures passing above superior constrictor
Auditory tube
Tensor veli palatini muscle
Ascending palatine artery
Palatine branch of ascending pharyngeal artery
Structure passing below inferior constrictor
Recurrent laryngeal nerve
Inferior laryngeal vessels
Enumerate structures passing between the constrictors.
Between superior and middle constrictor: Glossopharyngeal nerve + Stylopharyngeus muscle
Between middle and inferior constrictor
Internal laryngeal nerve + Superior laryngeal vessels
Pasavant’s ridge composition.
Horizontal fibers of palatopharyngeus that blend with superior constrictor
Pasavant’s ridge formed during
During swallowing when the soft palate is elevated
Significance of pasavant’s ridge
Together with the soft palate, it shuts off the nasopharynx from the oropharynx so that food is not regurgitated back into nasopharynx during swallowing
Killian Dehiscence formation and its clinical relevance.
Is a gap between the cricopharyngeal and thyropharyngeal muscle fibers of the inferior constrictor. The thyropharyngeal fibers run obliquely while cricopharyngeal fibers run horizontally resulting in a gap on posterior aspect of pharynx. This is a weak area and there is potential for diverticulum (outpouching of mucosa or submucosa)
Efferent and afferent fibers of the GAG reflex.
Afferent from Glossopharyngeal nerve
Efferent from Vagus nerve
Adenoids
hypertrophy of pharyngeal tonsils
Functions of larynx
Voice box (phonation) Allow passage of air into respiratory tract as it is part of it
Extent of larynx
Epiglottis upper border to lower border of cricoid cartilage
(C3 to C6 levels)
Difference between male and female thyroid cartilage
Larger in males
Angle is more prominent in males
Angle between the laminae at the angle of the thyroid cartilage is 90 degrees in males but 120 in females
Name the paired and unpaired cartilages of larynx.
3 paired:
Arytenoid
Corniculate
Cuneiform
3 unpaired:
Cricoid
Thyroid
Epiglottis
Thyroid cartilage lies at which level
C4 - C5
Structures attaching to thyroid cartilage superior and inferior borders of lamina.
Superior border: Thyrohyoid ligament and membrane
Inferior border: Cricothyroid ligament
The only unpaired ligament attaching to the internal surface of thyroid cartilage is the
Thyroepiglottic ligament
connections of epiglottis from above downwards
To tongue via the glossoepiglottic ligament
To hyoid bone via the hyoepiglottic ligament
To thyroid cartilage via the thyroepiglottic ligament
Name the intrinsic and extrinsic ligaments/membranes of the pharynx
intrinsic
- Vocal ligament
- Quadrangular membrane
- Vestibular ligament
- Cricovocal ligament
Extrinsic
- Thyroepiglottic ligaments
- Thyrohyoid ligaments
- Thyrohyoid membrane
- Cricothyroid ligament
- Cricotracheal ligament
Structures that form the true and false vocal cords, as well as their attachments.
True vocal cords; Cricovocal ligament upper thickened margin
Attaches to cricoid arch
False vocal cords; lower margin of Quadrangular membrane
Attaches to aryepiglottic fold
3 parts of the laryngeal cavity and their extent.
Vestibule/Supraglottic part; from laryngeal inlet to vestibular fold below
Ventricle/Sinus; between vestibular and vocal folds
Infraglottic part; from vocal fold to lower border of cricoid cartilage
The “oil can of the larynx” refers to which structure?
Hilton’s pouch/Saccule, a soft tissue mass or appendix rich in mucous glands whose secretions keep the vocal cords moist
Compare and contrast the false and true vocal cords.
*Hint: Include type of epithelium lining
False vocal cords
- do not take part in phonation
- gap between them is called rima vestibule
- lined by pseudostratified columnar epithelium
- do not contain muscles within the folds, but has the vestibular ligament
- rich in blood capillaries in their submucosa so appear pink
True vocal cords
- take part in phonation
- gap between hem is called rima glottis
- lined by stratified non-keratinized squamous epithelium
- contain vocalis muscles within the folds and also has vocal ligament
- lack capillaries in submucosa so appear white
The most narrow part of larynx and state its boundaries.
Rima glottis
- bounded laterally by vocal folds (anterior 3/5th) and vocal processes of arytenoid cartilages (posterior 2/5th)
- anteriorly by thyroid cartilage
- posteriorly by interarytenoid fold
True or false: The anterior 2/5th of the rima glottis is inter-cartilaginous.
False: It’s the anterior 3/5th of the rima glottis that is actually inter-membranous (between vocal folds)
The cricotracheal ligament attaches the cricoid to which tracheal ring?
1st
Structures piercing the thyrohyoid membrane.
Superior laryngeal vessels
Internal laryngeal nerve
*THINK: Structures passing between inferior and middle constrictor.
Name the depressors of the larynx.
Sternohyoid
Sternothyroid
Omohyoid
The primary elevators attach to the ____ while the secondary elelvators of larynx attach to the ____>
Primary elevators attach to tyroid cartilage
Secondary elevators attach to hyoid
Larynx mucous membrane supplied by
Vagus nerve
Sensory supply to larynx above vocal folds and below vocal folds.
Above is by the internal laryngeal nerve
Below is by the recurrent laryngeal nerve
Effect of injury on phonation to external laryngeal nerve? recurrent laryngeal nerve? both nerves?
If external laryngeal is damaged, the cricothyroid which it supplies is not able to tense the vocal cord resulting in weakness of phonation because the vocalis is still able to tense one part of the folds as it is innervated by recurrent laryngeal nerve
If recurrent laryngeal nerve damaged, the vocal cords are held in between adduction and abduction.. Unilateral damage results in a hoarse voice as the other half of the muscles on the other side are working. Bilateral damage affects phonation and breathing.
If both nerves are injured, the vocal cords are abducted more and there is no phonation, although breathing is possible.
Rima glottidis refers to
Abduction of vocal cords caused by damage to both external and recurrent laryngeal nerves = paralysis of intrinsic muscles
The sinus of Morgagni refers to
Ventricle/sinus of larynx
