Head & Neck 1 - Larynx Flashcards
from what vertebral levels does the larynx extend from?
C3-C6 (root of tongue > beginning of trachea)
what major vein and artery are related to the larynx?
common carotid artery
internal jugular vein
what are the three unpaired laryngeal cartilages?
thyroid
cricoid
epiglottis
what are the three paired laryngeal cartilages?
arytenoid
corniculate
cuneiform
is cricoid cartilage paired or unpaired?
unpaired
what is the largest unpaired laryngeal cartilage?
thyroid cartilage
which laryngeal cartilage is the only complete ring around the trachea?
A: thyroid
B: arytenoid
C: cuneiform
D: cricoid
D: cricoid cartilage
what forms the laryngeal prominence (Adam’s apple)?
fusion of the right and left lamina of the thyroid cartilage
what occurs to the laryngeal prominence in males following puberty?
enlarges & becomes prominent as the Adam’s apple
what happens when pressure is applied to the cricoid cartilage?
it can completely close off the oesophagus, which is located directly posterior.
what is the main function of the epiglottis?
protects the airway - closes over laryngeal inlet during swallowing, prevents food entering trachea
which paired laryngeal cartilages articulate with the cricoid cartilage?
arytenoid cartilages
which cartilages are found within the aryepiglottic folds and serve as structural support?
A: arytenoid cartilages
B: cuneiform cartilages
C: corniculate cartilages
D: thyroid cartilages
C: cuneiform cartilages
where are the corniculate cartilages located in relation to the arytenoid cartilages?
superior to the arytenoid cartilages - attached to the aryepiglottic folds
what membrane connects the hyoid bone to the thyroid cartilage?
A) cricothyroid ligament
B) quadrangular membrane
C) thyrohyoid membrane
D) aryepiglottic fold
C) thyrohyoid membrane
which structures pierce the thyrohyoid membrane?
A) External laryngeal nerve and inferior thyroid artery
B) Internal laryngeal nerve and superior laryngeal artery
C) Recurrent laryngeal nerve and cricothyroid artery
D) Inferior laryngeal nerve and subclavian artery
B) Internal laryngeal nerve and superior laryngeal artery
what is the function of the quadrangular membrane?
A) Forms the false vocal cords (vestibular folds)
B) Forms the true vocal cords (vocal folds)
C) Connects the epiglottis to the thyroid cartilage
D) Strengthens the cricothyroid ligament
A) Forms the false vocal cords (vestibular folds)
which ligament is the site for an emergency cricothyrotomy?
A) Thyrohyoid membrane
B) Quadrangular membrane
C) Cricothyroid ligament
D) Vestibular ligament
C) Cricothyroid ligament
which membrane forms the false vocal cords?
A: cricothyroid ligament
B: quadrangular membrane
C: thyrohyoid membrane
D: aryepiglottic fold
B: quadrangular membrane
the vocal fold is formed by a mucous membrane covering which structure?
A) Quadrangular membrane
B) Aryepiglottic fold
C) Cricothyroid ligament
D) Vocal ligament
D) Vocal ligament
which of the following statements about the vestibular folds (false vocal cords) is TRUE? (2)
A) They contribute to phonation
B) They prevent food from entering the airway
C) They are formed by the vocal ligament
D) They are located below the vocal folds
E) They protect the true vocal cords
B) They prevent food from entering the airway
E) They protect the true vocal cords
which of the following correctly describes the divisions of the laryngeal cavity?
A) Vestibule → Middle chamber → Infraglottic space
B) Supraglottic space → Glottis → Subglottic space
C) Epiglottic region → Aryepiglottic space → Vocal chamber
D) Pre-tracheal space → Vestibular chamber → Post-cricoid space
A) Vestibule → Middle chamber → Infraglottic space
which cartilage provides attachment for the aryepiglottic folds?
A) Cricoid cartilage
B) Thyroid cartilage
C) Corniculate cartilage
D) Arytenoid cartilage
D) Arytenoid cartilage
which of the following statements about the cricoid cartilage is TRUE?
A) It is the largest unpaired laryngeal cartilage
B) It articulates superiorly with the epiglottis
C) It is the only complete ring of cartilage around the airway
D) It has no articulations with other cartilages
C) It is the only complete ring of cartilage around the airway - the largest unpaired cartilage is the thyroid, not the cricoid; the cricoid articulates with the thyroid and arytenoid cartilages, NOT the epiglottis
which of the following correctly describes the function of the vocal and vestibular folds?
A) Both contribute to phonation
B) Vestibular folds protect the airway; vocal folds produce sound
C) Both protect the airway
D) Vestibular folds produce sound; vocal folds protect the airway
B) Vestibular folds protect the airway; vocal folds produce sound - only the true vocal cords (vocal folds) produce sound
a patient needs an emergency airway due to upper airway obstruction. Where would a cricothyrotomy be performed?
A) Through the thyrohyoid membrane
B) Between the hyoid bone and thyroid cartilage
C) Through the median cricothyroid ligament
D) Through the quadrangular membrane
C) Through the median cricothyroid ligament
which structure does the superior laryngeal artery pierce to enter the larynx?
A) Quadrangular membrane
B) Thyrohyoid membrane
C) Cricothyroid ligament
D) Aryepiglottic fold
B) Thyrohyoid membrane
Which cartilage is embedded within the aryepiglottic fold and provides structural support?
A) Arytenoid cartilage
B) Corniculate cartilage
C) Cuneiform cartilage
D) Cricoid cartilage
C) Cuneiform cartilage - corniculate sits on top of arytenoids, while cuneiform is within the aryepiglottic fold
which of the following is TRUE regarding the quadrangular membrane?
A) It runs from the hyoid bone to the cricoid cartilage
B) It forms the vocal ligament
C) It contributes to the false vocal cords (vestibular folds)
D) It contains the superior laryngeal artery
C) It contributes to the false vocal cords (vestibular folds) - cricothyroid ligament is what’s related to the true vocal cords
which structures (2) pierce the thyrohyoid membrane?
internal laryngeal nerve
superior laryngeal artery
what are the functions of the quadrangular membrane?
forms part of the false vocal cords (vestibular folds)
protects the airway
DOESN’T contribute to sound production
why is the median cricothyroid ligament clinically significant?
site of an emergency cricothyrotomy - procedure performed to create an airway in cases of upper airway obstruction
what is another name for the vestibular folds?
false vocal cords
what structure forms the true vocal cords?
the vocal fold - consists of a mucous membrane covering the vocal ligament
function of the vocal folds?
phonation (sound production)
what structure marks the transition from the larynx to the trachea?
inferior border of the cricoid cartilage
what do the intrinsic laryngeal muscles control?
control laryngeal inlet and vocal cords
which muscle is responsible for abducting (opening) the vocal cords?
A) Lateral cricoarytenoid
B) Transverse arytenoid
C) Posterior cricoarytenoid
D) Cricothyroid
C) Posterior cricoarytenoid - most laryngeal muscles adduct the vocal cords—posterior cricoarytenoid is the ONLY muscle that abducts them
a patient has a lesion of the recurrent laryngeal nerve. Which muscle would still be fully functional?
A) Posterior cricoarytenoid
B) Lateral cricoarytenoid
C) Cricothyroid
D) Thyroarytenoid
C) Cricothyroid - almost all intrinsic laryngeal muscles are innervated by the recurrent laryngeal nerve, except the cricothyroid (innervated by external laryngeal nerve)
which muscle is responsible for increasing pitch by tensing the vocal ligaments?
A) Vocalis
B) Cricothyroid
C) Posterior cricoarytenoid
D) Transverse arytenoid
B) Cricothyroid - vocalis fine-tunes pitch; cricothyroid increases pitch by tensing vocal ligaments
Which of the following is NOT innervated by the recurrent laryngeal nerve?
A) Cricothyroid
B) Thyroarytenoid
C) Transverse arytenoid
D) Oblique arytenoid
A) Cricothyroid - most laryngeal muscles supplied by the recurrent laryngeal nerve EXCEPT cricothyroid (supplied by external laryngeal nerve)
Which muscle primarily fine-tunes pitch rather than directly altering vocal cord length?
A) Cricothyroid
B) Vocalis
C) Posterior cricoarytenoid
D) Thyroarytenoid
B) Vocalis - cricothyroid tenses cords to raise pitch; vocalis fine-tunes pitch for subtle adjustments
a patient presents with hoarseness and an inability to produce high-pitched sounds. Which nerve is most likely affected?
A) Recurrent laryngeal nerve
B) External branch of the superior laryngeal nerve
C) Internal branch of the superior laryngeal nerve
D) Glossopharyngeal nerve
B) External branch of the superior laryngeal nerve - innervates the cricothyroid muscle which is responsible for high-pitched sounds
Which muscle is the primary (and only) abductor of the vocal cords?
A) Oblique arytenoid
B) Posterior cricoarytenoid
C) Cricothyroid
D) Thyroarytenoid
B) Posterior cricoarytenoid
what is the difference in action between the vocalis and cricothyroid muscles?
vocalis tenses vocal cords - fine-tunes pitch of voice
cricothyroid tenses vocal ligaments - produces higher-pitched sounds
which intrinsic laryngeal muscle is the only one to not be innervated by the recurrent laryngeal nerve? what nerve is it innervated by instead?
cricothyroid - innervated by external laryngeal nerve (vagus nerve > superior laryngeal n. > external laryngeal n.)
which two laryngeal intrinsic muscles are the only ones mainly involved in narrowing the laryngeal inlet?
A) Oblique arytenoid
B) Posterior cricoarytenoid
C) Cricothyroid
D) Thyroarytenoid
A) Oblique arytenoid; D) Thyroarytenoid
- narrowing laryngeal inlet prevents aspiration during swallowing
which two muscles are mainly involved in adducting (closing) the vocal cords?
A) Transverse arytenoid
B) Thyroarytenoid
C) Lateral cricoarytenoid
D) Posterior cricoarytenoid
A) Transverse arytenoid; C) Lateral cricoarytenoid
- adducting vocal cords closes airway
action of the vocalis muscle?
tenses vocal cords - fine-tunes pitch of voice
action of the cricothyroid muscle?
tenses vocal ligaments - produces higher-pitched sounds
action of the posterior cricoarytenoid muscle?
abducts (opens) vocal cords; primary abductor
action of the thyroarytenoid muscle?
narrows laryngeal inlet (pulls epiglottis down)
action of the oblique arytenoid muscle?
narrows laryngeal inlet (+adducts vocal cords)
action of the transverse arytenoid muscle?
adducts vocal cords (+narrows laryngeal inlet)
action of the lateral cricoarytenoid muscle?
adducts (closes) vocal cords
innervation of the posterior cricoarytenoid muscle?
recurrent laryngeal nerve
innervation of the cricothyroid muscle?
external laryngeal nerve
what is the primary motor nerve of the muscles of the larynx?
recurrent laryngeal nerve (CNX branch) - supplies all intrinsic muscles of the larynx except cricothyroid
what is the sensory innervation ABOVE the vocal cords?
internal laryngeal nerve (branch of superior laryngeal nerve, CN X)
what is the sensory innervation BELOW the vocal cords?
recurrent laryngeal nerve (branch of CN X)
through which membrane does the internal laryngeal nerve pass?
thyrohyoid membrane
which artery supplies the upper part of the larynx?
superior laryngeal artery
which artery supplies the lower part of the larynx?
inferior laryngeal artery
from which artery does the superior laryngeal artery arise from?
superior thyroid artery - branch of external carotid artery
from which artery does the inferior laryngeal artery arise from?
inferior thyroid artery - branch of thyrocervical trunk from the subclavian artery
the thyrocervical trunk is a direct branch of which major artery?
subclavian artery
describe the arterial supply to the larynx
upper part of larynx - supplied by superior laryngeal artery (branch of superior thyroid artery)
lower part of larynx - supplied by inferior laryngeal artery (branch of inferior thyroid artery; branch of thyrocervical trunk form subclavian artery)
describe the motor innervation to the larynx
recurrent laryngeal nerve - supplies all intrinsic laryngeal muscles except the cricothyroid
external laryngeal nerve (branch of superior laryngeal nerve from vagus nerve) - supplies cricothyroid
what nerve ultimately supplies the muscles of the larynx?
vagus nerve
describe the sensory innervation of the larynx
recurrent laryngeal nerve - sensory innervation to the larynx BELOW the vocal cords
internal laryngeal nerve (branch of superior laryngeal nerve from vagus nerve) - sensory innervation to the larynx ABOVE the vocal cords
which nerve provides sensory innervation ABOVE the vocal cords?
A) External laryngeal nerve
B) Internal laryngeal nerve
C) Recurrent laryngeal nerve
D) Glossopharyngeal nerve
B) Internal laryngeal nerve
which artery supplies the lower part of the larynx?
A) Superior laryngeal artery
B) Inferior laryngeal artery
C) Superior thyroid artery
D) External carotid artery
B) Inferior laryngeal artery
which structure does the superior laryngeal artery travel with as it enters the larynx?
A) External laryngeal nerve
B) Internal laryngeal nerve
C) Recurrent laryngeal nerve
D) Inferior laryngeal nerve
B) Internal laryngeal nerve - both pass through the thyrohyoid membrane
Which nerve loops under the aortic arch before ascending to the larynx?
A) Right recurrent laryngeal nerve
B) Left recurrent laryngeal nerve
C) External laryngeal nerve
D) Internal laryngeal nerve
B) Left recurrent laryngeal nerve - right recurrent laryngeal nerve loops under the right subclavian artery instead
damage to which nerve would result in an inability to produce high-pitched sounds?
A) Internal laryngeal nerve
B) External laryngeal nerve
C) Recurrent laryngeal nerve
D) Phrenic nerve
B) External laryngeal nerve - external laryngeal nerve innervates cricothyroid, which tenses the vocal cords for higher-pitched sounds
Which nerve is responsible for sensation in the larynx below the vocal cords?
A) External laryngeal nerve
B) Internal laryngeal nerve
C) Recurrent laryngeal nerve
D) Hypoglossal nerve
C) Recurrent laryngeal nerve - internal laryngeal nerve handles above the vocal cords, while the recurrent laryngeal nerve handles below
