Interval 14: Larynx Flashcards
Vestibule of the larynx begins at the _____________ and extends to the ___________.
- larynx behind the epiglottis
- vestibular folds
What is the ventricle?
-narrow ellipse-shaped space situated between the vestibular folds and vocal folds
What is the name of the space inferior to the vocal folds? What is the rima glottis and the glottis?
- infraglottic space
- rima glottidis is the opening between the vocal folds
- glottis consists of the rima glottidis and vocal folds
Name the cartilages of the larynx and what is created at their articulation.
- cricoid
- thyroid
- pair of arytenoid cartilages
- synovial joints
Where can one find the arytenoid cartilages and contain what 2 kinds of processes?
- posterosuperior aspect of the cricoid cartilage
- muscular and vocal processes
Where do the vocal ligaments extend from and to? What is it covered by?
- extend anteriorly from the vocal processes of the arytenoids and attach to the posterior aspect of the thyroid cartilage
- covered by thyroarytenoid muscle, which is then covered by mucosa
- *these 3 structures form the vocal cord/fold
What is the only cartilage of the larynx that completely encircles the airway?
-cricoid cartilage
Full adduction of the vocal ligaments causes the vocal folds to meet in the midline, closing the glottis during what 3 activities?
- swallowing
- defecation
- urination
Functions and mechanisms of the thyroarytenoid and cricothyroid muscles
- thyroidarytenoid: relax vocal ligaments by pulling the arytenoid cartilages closer to the thyroid cartilage
- cricothyroid muscles tense the vocal ligaments by rocking the superior aspect of the thyroid anteriorly at its articulation with the cricoid, increasing the distance between these 2 cartilages
Where is the vocalis muscle and what does it do?
-forms the medial aspect of the thyroarytenoid and adjusts the tension in small segments of the vocal ligament
All of the muscles of the larynx are innervated by what nerve? Any exceptions?
- inferior laryngeal nerve (branch of recurrent laryngeal nerve of the vagus)
- except for cricothyroid muscle which is innervated by external branch of the superior laryngeal nerve
Describe the innervation of mucosa above and below the vocal folds
- internal branch of superior laryngeal nerve innervates above the folds
- inferior laryngeal nerve innervates mucosa below the vocal folds
Describe what happens in the superior laryngeal nerve lesions.
-Superior: largely asymptomatic because its fibers are mainly sensory. If the motor fibers of the external branch leading to the cricothyroid are affected, patient may experience mild hoarseness and a slight decrease in vocal strength, with tendency to produce monotonous speech
How can recurrent laryngeal nerves be lesioned? Which one is more commonly lesioned? What is the result of a lesion?
- both susceptible to injury in surgical procedures involving the thyroid gland
- left is injured more commonly because of its course through the mediastinum (aortic aneurysm)
- results in fixed vocal cord and transient hoarseness
The nasal cavity begins at the ___________ and communicated posteriorly with what?
- external nares
- nasopharynx through the choanae
The nasal septum divides the nasal cavity in the midline and the lateral wall of the nasal cavity contains 3 scroll-like bones which form what?
- superior
- middle
- inferior conchae
Where does the posterior ethmoidal cells drain?
-superior meatus
What drains into the middle meatus?
-anterior and middle ethmoid air cells, frontal sinus, maxillary sinus