Larynx Flashcards
larynx functions
- phonation
- sphincter for respiratory system (regulates air to/from lungs, allows inc in abd pressure via valsalva)
- acts w/ oral cavity, oral pharynx in process of deglutition
upper boundary of larynx
tip of epiglottis, opposite to C3/C4
lower boundary of larynx
lower border of cricoid cartilage, opposite to C6
the larynx opens into the ________ above and is continuous w/ the _______ below
the larynx opens into the LARYNGEAL PT OF THE PHARYNX above and is continuous w/ the TRACHEA below
3 median (unpaired) cartilages of the larynx
- epiglottis
- thyroid cartilage
- cricoid cartilage
3 paired cartilages of the larynx
- arytenoid
- corniculate
- cuneiform
thyroid cartilage has 2 laminae that meet at midline and form the ________________, with the ________________ at its rostral margin
thyroid cartilage has 2 laminae that meet at midline and form the LARYNGEAL PROMINENCE, with the THYROID NOTCH at its rostral margin
the posterior border of each thyroid cartilage lamina forms _______________
the posterior border of each thyroid cartilage lamina forms SUPERIOR AND INFERIOR HORNS
Which m. attach to the oblique lines of the thyroid cartilage?
thyrohyoid
sternothyroid
inferior constrictor
Which structures attach to superior border of thyroid cartilage?
- throhyoid membrane
- inferior border to cricothyroid membrane
vertebral level of cricoid cartilage
C6, lies below thyroid cartilage
first and only complete tracheal ring
cricoid cartilage
articular facets on the cricoid cartilage
on lateral surface –> for inferior horn of thyroid cartilage
on upper border for articulation w/ base of arytenoid cartilage
^both synovial joints
arytenoid cartilages
- location
- articulations
- back of larynx
base: articulates w/ upper border cricoid cartilage
apex: supports corniculate cartilage
vocal process: projects forward, attachment to vocal ligament
muscular process: lateral
rima glottidis
space between vocal cords
varies w/ position of vocal folds (depends on position of arytenoids)
epiglottis
- flexible (elastic cartilage)
- behind root of tongue
- upper edge is free
hyoepiglottic ligament
connects front of epiglottis to body of hyoid bone
thyroepiglottic ligament
connects stalk of epiglottis to thyroid cartilage
aryepiglottic folds
located at the entrance of the larynx
extend from the lateral borders epiglottis to the arytenoid cartilages
anterior mucosa of epiglottis is reflected onto tongue forming 3 ________ and ________
anterior mucosa of epiglottis is reflected onto tongue forming 3 GLOSSOEPIGLOTTIC FOLDS and VALLECULAE
vallecula
space between posterior portion of tongue and epiglottis
during swallowing, food passes over posterior portion of tongue through the _______, and down into _________ can be trapped before entering esophagus
during swallowing, food passes over posterior portion of tongue through the VALLECULA, and down into PIRIFORM RECESS where it can be trapped before entering esophagus
corniculate cartilages
- small conical nodules
- sit superior to and articulate w/ apices of arytenoid cartilages and prolong them
- can be seen as projections into the vocal area
cuneiform cartilages
- small, rod shaped
- in each aryepiglottic folds –> prod small elevation
- NO articulations w/ any other cartilage
Which cartilages support the aryeepiglottic fold?
corniculate and cuneiform cartilages
arytenoids glide/rotate on the lamina of the _____, changing the angle between _____
arytenoids glide/rotate on the lamina of the CRICOID, changing the angle between VOCAL LIGAMENTS
thyrohyoid membrane has openings for which structures
internal laryngeal n. (br. of superior laryngeal br. of vagus)
superior laryngeal a.
cricotracheal membrane
connects cricoid cartilage to first tracheal ring
quadrangular membrane
between epiglottis and arytenoid cartilages
- lower free edge: vestibular ligament
- upper free edge: aryepiglottic fold
vestibular ligament lies within the _______ (________)
vestibular ligament lies within the VESTIBULAR FOLD (FALSE VOCAL FOLDS)
conus elasticus origin/attachments
upper edge: forms vocal ligament
lower edge: attached to upper border of cricoid cartilage
anterior attachment: thyroid cartilage
posterior attachment: arytenoid cartilage
vocal ligament
upper free edge of conus elasticus
attached anteriorly to deep surface of thyroid cartilage and posteriorly to vocal process of arytenoid cartilage
pt of the TRUE vocal cords
conus elasticus functions
- sound production (vibrate)
2. close rima glottidis (stops outflow of air, upward movement of diaphragm, inc abd cavity pressure)
ventricle
area between true and false vocal folds
entrance into sinus of the larynx
vestibule
inlet above false vocal cords
false vocal cords
vestibular folds (overlay vestibular ligaments)
- little/no pt in voice prod
- protective role
vocal cords (folds)
combo of
- vocal ligaments
- thyroarytenoid m.
- vocals m.
- mucosa above ^
glottis
combo of vocal cords AND space between them (rima glottidis)
laryngeal inlet
faces backward and upward, opens into laryngeal pt of pharynx
bounded…
anteriorly by upper margin of epiglottis
posteriorly and below by arytenoid cartilages
laterally by aryepiglottic folds
laryngeal cavity
extends from laryngeal inlet to lower border cricoid cartilage
narrow region –> rima vestibuli
narrowest region –> rima glottidis
rima vestibuli
narrow region of laryngeal cavity between the vestibular (false) folds
rima glottidis
narrow region of laryngeal cavity between true vocal folds
lateral recess between vestibular fold and vocal fold
sinus of the larynx
entrance into sinus is the ventricle
blind uppermost recess of the sinus of the larynx, extending between vestibular fold and thyroid cartilage
saccule of the larynx
laryngocele
abnormal congenital or acquired air-filled sac communicating w/ the ventricle of the larynx
sx: coughing, hoarseness, neck pain if laryngocele becomes infected, upper airway obstruction
extrinsic m. of larynx
elevators of larynx
digastric
stylohyoid
mylohyoid
(suprahyoids)
stylopharyngeus
palatopharyngeus
thyrohyoid
extrinsic m. of larynx
depressors of larynx
sternohyoid m.
intrinsic m. of larynx controlling size of laryngeal inlet
- oblique and transverse arytenoids
- aryepiglottic m.
oblique and transverse arytenoids
- connect posterior and lateral surfaces of both arytenoid cartilages
- narrows the laryngeal inlet and ADDUCTS vocal cords
aryepiglottic m.
- upper portion of oblique arytenoids
- extend from arytenoid cartilages to lateral edge of epiglottis
- draw aryepiglottic folds inward, narrow laryngeal inlet (sphincter of inlet during swallowing)
cricothyroid m.
inc distance between angle of thyroid cartilage and vocal processes of arytenoid cartilages
–> INC length and TENSION of vocal cords
–> raises pitch of voice
–> external br. superior laryngeal n. of vagus
paralysis of cricothryoid m.
low-pitched voice
thyroarytenoid
pulls arytenoid cartilage forward toward thyroid cartilage
–> SHORTENS and RELAXES vocal cords
–> lowers pitch of voice
vocalis m.
more medial portion of thyroarytenoid m.
directly in contact w/ vocal ligament
fine control of vocal cords (relaxes segments of vocal ligaments, adjusting pitch)
thyroepiglottic m.
pulls laterally on aryepiglottic fold and epiglottis (widens laryngeal inlet)
represents superior fibers of thyroarytenoid m. (fan out to quadrangular membrane/epiglottis)
adductors of vocal cords
lateral cricoarytenoid
transverse arytenoid
whisperer’s muscle
lateral cricoarytenoid action
rotates arytenoids MEDIALLY, leaving a space posterior to them
abductor of vocal cords
posterior cricoarytenoid
- pivots arytenoids so that vocal process moves laterally
bilateral paralysis of posterior cricoarytenoid
adduction of vocal cords
potential suffocation
vagus n. –> superior laryngeal n. –> ____ and ____
vagus n. –> superior laryngeal n. –> INTERNAL and EXTERNAL LARYNGEAL N.
all laryngeal m. innervated by __________ n. EXCEPT which m.?
br. of recurrent laryngeal
EXCEPT cricothyroid (external br. superior laryngeal n. of vagus)
sensory innervation to mucosa below vocal cords
recurrent laryngeal n. (br. of vagus)
sensory innervation to mucosa above vocal cords
internal laryngeal n. (br of superior laryngeal n. of CN X)
How does the recurrent laryngeal n. enter the larynx?
passes deep to cricopharynxgeus and inferior constrictor to enter larynx
sensation in piriform recess
internal laryngeal n.
recurrent laryngeal n. becomes _________ when it enters the larynx
recurrent laryngeal n. becomes INFERIOR LARYNGEAL N. when it enters the pharynx
superior laryngeal n. block
- used to abolish the cough reflex during laryngoscopy and bronchoscopy
- inject anesthesia thru thyrohyoid membrane between hyoid and thyroid cartilage to anesthetize region superior to the vocal fold.
afferent limb of cough reflex
internal laryngeal n.
efferent limb of cough reflex
signals transmitted back from cerebral cortex and medulla via vagus, phrenic and intercostal n. to glottis, intercostal, diaphragm, etc.
cough reflex response
- glottis closes under contraction of transverse arytenoid and lateral cricoarytenoid m. by the recurrent laryngeal n.
- expiration of air under pressure from lungs (via contraction of abd m.)
- vocal cords relax –> explosive release of air from larynx
spasm of laryngeal m.
foreign object lodged in vestibule –> laryngeal m. spasm, close rima vestibuli and rima glottidis
–> complete blockage, speechless, may completely seal off larynx/choke person
–> administer HEIMLICH MANEUVER
valsava maneuver
forceful expiator effort against closed airway used during coughing/sneezing/defecation/childbirth
- vestibular and vocal folds abduct widely as lungs inflate during deep inspiration
- vestibular and vocal cords are voluntarily adducted at end of inspiration
- abd wall m. contract to inc intra-and and sub-glottic pressure
injury to superior laryngeal n.
- loss of sensation (internal laryngeal n.) from upper pt of larynx and piriform recess (inactivates cough reflex)
- paralysis of cricothyroid (external laryngeal n.) –> monotonous voice bc vocal cords can’t be tensed
injury to recurrent laryngeal n.
bilateral –> inability to abduct, adduct, and relax the vocal cords
- -> hoarseness, difficulty breathing during forced respiration bc cords cannot be widely abducted)
- -> STRIDOR (high pitch)
inability to close laryngeal inlet during swallowing
–> ASPIRATION of food into trachea
unilateral recurrent laryngeal nerve paralysis
pt asked to take a deep breath –> ABducting vocal cords
sx: breathiness, low intensity, low pitch, production of 2 pitches at one time
blood supply to upper half larynx
superior laryngeal a. (br. of superior thyroid a.)
blood supply to lower half larynx
inferior laryngeal a. (br. of inferior thyroid a.)
lymph drainage ABOVE vocal cords
drain into superior deep cervical nodes
–> L or R venous angle
lymph drainage BELOW vocal cords
drain into pretracheal or paratracheal nodes –> inferior deep cervical nodes
–> L or R venous angle
bolus pushed back into orpharynx
(mechanics of swallowing)
m. and n. involved
mylohyoid (V3)
elevating and tetracting tongue
(mechanics of swallowing)
m. and n. involved
styloglossus (XII)
palatoglossus (X)
soft palate elevated and tensed
(mechanics of swallowing)
m. and n. involved
levator veli palatini (X)
tensor veli palatini (V3)
laryngeal inlet closed
(mechanics of swallowing)
m. and n. involved
aryepiglottic
oblique arytenoids
recurrent laryngeal n. (CN X)
glottis closed (mechanics of swallowing)
m. and n. involved
transverse, oblique arytenoids, lateral cricoarytenoid
recurrent laryngeal n. (CN X)
larynx and larynx elevated
(mechanics of swallowing)
m. and n. involved
stylopharyngeus (IX)
salpingopharyngeus and palatopharyngeus (X)
laryngitis
swollen PINK vocal cords, almost same color as surrounding tissue (normal: white, shiny)
causes: usually viral/bacterial, may have noninfectious causes (xs vocal use, smoking, xs alcohol consumption, laryngeal trauma)
sx: hoarsness, dry, burning throat, coughing, difficulty swallowing
laryngeal edema
abnormal accumulation of fluid in larynx
causes:
- infections
- retropharyngeal abscesses
- surgery of larynx/neck
- drug rxn
can cause swelling of membranes around larynx, narrowing of glottis (life-threatening)
tx: intubation or emergency cricothyrotomy/tracheostomy
laryngeal papillomas
benign epithelial tumors caused by infection w/ HPV
sx: hoarsness, proportional to size of papilloma, may lock airway –> difficulty breathing
tx: laser surgery
vocal cord polyps
small, mostly unilateral, swellings in mucous membranes of vocal cords
via voice abuse, chronic laryngeal allergic rxns, chronic inhalation of irritants
vocal cord nodules
small, inflammatory or fibrous growth –> develops on vocal cords of people who constantly strain their voices
usually appear in PAIRS
structural resemblance to a CALLUS on hand
voice becomes breathy, hoarse
endotracheal intubation
flexible plastic tube into trachea to maintain open airway
performed on critically injured, ill, anesthetized pts w/
- upper airway obstruction
- respiratory failure
- loss of consciousness
- undergoing prolonged surgery under anesthesia
- have risk of pulmonary aspiration
