clinical anatomy of the larynx Flashcards
1
Q
what is the upper airway?
A
from the nasal cavity to the up to the larynx
2
Q
what is the lower airway?
A
everything beyond the trachea
3
Q
what are the 3 parts of the pharynx?
A
nasopharynx
oropharynx
laryngopharynx
4
Q
what is the most superior part of the respiratory tract?
A
nasal cavity
5
Q
what type of organ is the nasal cavity?
A
dual olfactory and respiratory organ
6
Q
what are the functions of the nasal cavity?
A
- Warms and humidifies inspired air
- Removes and traps pathogens from inspired air
- Sense of smell
- Drains paranasal sinuses and lacrimal ducts
7
Q
where does the nasal cavity extend?
A
nostril to nasopharynx
8
Q
what are the 3 parts of the nasal cavity?
A
- vestibule - area around the nostrils to the nasal cavity
- respiratory region
- olfactory region - found at the apex of the nasal cavity
9
Q
what lines the respiratory region of the nasal cavity?
A
ciliated pseudostratified epithelium + goblet cells
10
Q
what is the function of the respiratory region of the nasal cavity?
A
responsible for trapping pathogens and particulates within inspired air
11
Q
what is the function of the olfactory region of the nasal cavity?
A
sense of smell
12
Q
describe the innervation of the nose
A
- olfactory region is lined by olfactory cells with olfactory receptors
- olfactor nerves run through cribiform plate to provide special sensory innervation to the nose.
13
Q
where is the oral cavity found?
A
spans between the oral fissure anteriorly and the opening of the oropharynx posteriorly
14
Q
what are the 2 major divisions of the oral cavity?
A
vestibule
oral cavity proper
15
Q
what is the vestibule of the oral cavity?
A
space between the lips/cheeks and the gums/teeth
16
Q
where is the oral cavity proper? what are its borders?
A
Roof - anterior hard palate and posterior soft palate
Floor
Cheeks (buccinator muscle)
17
Q
what separates the nasal cavity from the oral cavity?
A
hard palate
18
Q
what covers the hard palate superiorly and inferiorly?
A
superiorly - pseudostratified columnar epithelium
inferiorly - oral mucosa (stratified squamous epithelium)
19
Q
what is the soft palate?
A
muscular (not bony) continuation of the hard palate posteriorly
20
Q
describe the structure of the cheeks
A
made up of the buccinator muscle
lined internally by the oral mucous membrane
21
Q
what supplies the sensory innervation of the oral cavity?
A
branches of the trigeminal nerve
22
Q
what are the functions of the oral cavity?
A
digestion
communication
breathing
23
Q
what is the bony skeleton of the oral cavity made up of?
A
maxilla and mandible - house the upper and lower teeth
24
Q
what is the pharynx?
A
Muscular tube connecting oral and nasal cavities to the trachea and oesophagus
25
what controls the shape of the pharynx and the propulsion of food into the oesophagus
controlled by 2 sets of pharyngeal muscles - circular and longitudinal
26
where is the nasopharynx?
found between the base of the skull and the soft palate.
| continuous with the nasal cavity
27
what is the function of the nasopharynx?
respiratory function performed by conditioning inspired air and propagating it into the larynx
28
what lines the nasopharynx?
ciliated pseudostratified columnar epithelium with goblet cells
29
where is the oropharynx?
located between the soft palate and the superior border of the epiglottis
30
what structures does the oropharynx contain?
- posterior 1/3 of the tongue
- lingual tonsils
- palatine tonsils
- superior constrictor muscle
31
where is the laryngopharynx?
located between the epiglottis and the inferior border of the circoid cartilage (C6)
continues inferiorly with the oesophagus
32
how many cartilages is the larynx made of?
9
33
what spinal level is the larynx found at?
C3-C6
34
what does the larynx connect to superiorly and inferiorly?
hyoid bone superiorly
| trachea inferiorly
35
what happens to the male larynx after puberty?
enlarges with the saggital diameter and nearly doubles
| all the cartilages increase in both size and weight
36
what are the 3 unpaired cartilages of the larynx?
epiglottis
thyroid
cricoid
37
where are the 3 paired cartilages of the larynx?
arytenoid
corniculate
cuneiform
38
what spinal level is the hyoid at?
C3
39
what is the function of the intrinsic laryngeal muscles?
act to move the components of the larynx for phonation and breathing
40
what is the epiglottis?
a leaf shaped plate of elastic cartilage which marks the entrance to the larynx
made of yellow cartilage and never calcifies
41
what is the function of the epiglottis?
During swallowing, the epiglottis flattens and moves posteriorly to close off the laryngeal inlet and prevent aspiration of food. Closes as a valve and forces food down the lateral food canals
42
what is the thyroid cartilage and where is it found?
lies just beneath the hyoid bone
| composed of 2 sheets (laminae) which fuse anteriorly to form the laryngeal prominence
43
what does the lateral thyrohyoid ligament connect?
connects the superior horns of the thyroid cartilage to the hyoid bone
44
what do the inferior horns of the thyroid cartilage articulate with?
cricoid cartilage
45
what is the only complete circle of cartilage in the larynx or trachea?
cricoid cartilage
46
what does the cricoid cartilage connect with?
superiorly - inferior horns of the thyroid cartilage
posteriorly - 2 arytenoid cartilages by synovial joints
inferiorly - trachea
47
how does the cricoid cartilage attach to the trachea?
cricotracheal ligament
48
what are the largest of the paired cartilages?
arytenoids
49
what is the vocal process?
the anterior point of the aytenoids
50
describe the arrangement of the paired cartilages
corniculate cartilages sit atop the arytenoids
| cuneiform are above the corniculate located within the ary-epiglottic folds
51
what is the function of the extrinsic ligaments of the larynx?
act to attach the components of the larynx to external structures (such as the hyoid and the cricoid cartilage
52
what is the thryohyoid membrane? what structures pass through it?
between the thyroid and hyoid bone
| pierced laterally by the superior laryngeal vessels and internal laryngeal nerve
53
what forms the vocal folds?
cricothyroid ligament with the overlying epithelium
54
where is the quadrangular membrane?
act to attach the components of the larynx to external structures (such as the hyoid and the cricoid cartilage).
55
what are the 3 regions of the larynx?
vestibule - laryngeal opening to the vestibular folds
ventricle - between the vestibular and vocal folds
infraglottis area - below the vocal folds, continuous with the trachea
56
what covers the vocal and vestibular folds where they connect? why is this important?
covered by non-keratinized, stratified squamous epithelium
protects the tissue from the effects of the considerable mechanical stresses that act on the surfaces of the vocal folds
57
what gives the vocal folds shape?
vocal ligaments
58
what is the rima glottidis?
space between the vocal folds
59
what gives the vestibular fold shape?
the quadrangular membrane
60
what are the false cords?
free edge above the vocal cords
| the vestibular ligament which is the inferior border of the quadrangular membrane
61
what are the functions of the larynx?
- protection of the airway
- effort closure in coughing, sneezing and abdominal straining
- phonation
62
what is the rate of flow in a tube proportional to?
the radius of the tube to the power of 4
63
what is stridor?
high pitched whistling breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree
64
what is stridor a sign of?
narrowed or obstructed airway
65
during breathing which way is the epiglottis pointed?
upward during breathing
66
how does the larynx deflect food boluses into the oesophagus away from the larynx?
- elevation of the hyoid bone pulls the larynx upwards
- contraction of the aryepiglotticus muscle causes epiglottis to flatten into a more horizontal position and into contact with arytenoid cartilage
- closes laryngeal inlet
67
what are the phases of the cough reflex and what happens during them?
1) Inspiratory – generates intrathoracic volume
2) Compression – concomitant closure of the vocal cords with contraction of muscles of the chest and abdominal wall causes a rapid rise in intrathoracic and intra-abdominal pressure
3) Expiratory phase – the glottis opens with explosive airflow
68
what is the function of coughing?
dislodges mucus, fluids, irritants from the airway
69
what is the function of sneezing?
expels mucus from the nasal cavity
70
how does vomiting occur?
intra-abdominal pressure and relaxation of oesophageal sphincters allows expulsion of vomitus
71
how does defecating occur?
intraabdominal pressure and relaxation of anal sphincters allows expulsion of faeces
72
what do the intrinsic laryngeal muscles control?
the shape of the rima glottidis by acting on the arytenoid cartilage to adduct or abduct the vocal cords
the length and tension of the vocal folds to alter pitch
73
what is the function of the lateral cricoarytenoid muscles?
major adductors of the vocal folds
| narrows the rima glottidis, modulating the tone and volume of speech
74
what are the attachments of the lateral cricoarytenoids?
Originates from the arch of the cricoid cartilage, and attaches to the muscular process of the arytenoid cartilage.
75
what is the innervation of the lateral cricoarytenoids?
inferior laryngeal nerve (branch of the recurrent laryngeal)
76
what is the function of the transverse and oblique arytenoids?
adduct the arytenoid cartilages, closing the posterior portion of rima glottidis. This narrows the laryngeal inlet
77
what are the attachments of the transverse and oblique arytenoids?
Spans from one arytenoid cartilage to the opposite arytenoid
78
what is the innveration of the transverse and oblique arytenoids?
inferior laryngeal nerve
79
how can pitch be altered?
by changing the tension of the vocal folds
allows rotation to bring together or approximate the lamina of the thyroid cartilage and the arch of the cricoid cartilage
alters length and tension of the vocal cords
80
what do the thyroarytenoids do?
acts to relax the vocal ligament, allowing for a softer voice
81
what are the attachments of the thyroarytenoids?
Originates from the inferoposterior aspect of the angle of the thyroid cartilage, and attaches to the anterolateral part of the arytenoid cartilage
82
what is the innervation of the thyroarytenoid muscles?
inferior laryngeal nerve
83
what are the branches of the superior laryngeal nerves>
internal and external laryngeal nerve
84
what does the internal laryngeal nerve do?
sensory innervation to above the vocal cords
85
what does the external laryngeal nerve do?
motor to cricothyroid muscle
| controls pitch
86
what does the recurrent laryngeal nerve do?
Motor to all intrinsic muscles EXCEPT cricothyroid
Sensory innervation to area below vocal cords
PHONATION
87
what does a lesion to the recurrent laryngeal nerve cause?
vocal cord paralysis (inability to abduct laterally)
hoarseness (aphonia and stridor)
88
what does a lesion to the external laryngeal nerve cause?
- cricothyroid paralysis preventing higher pitched phonation
| - weak voice, low pitch, easily tires, reduced range
89
what is the superior laryngeal artery a branch of?
superior thyroid artery
| branch of the external carotid artery
90
what does the superior laryngeal artery supply blood to?
supplies blood to the muscles, mucous membrane, and glands of the larynx,
91
what is the inferior laryngeal artery a branch of?
inferior thyroid artery
| derived from the thyrocervical trunk
92
describe the venous drainage of the larynx
- Superior thyroid vein drains above the glottis into the internal jugular
- Inferior thyroid vein drains below the glottis into the brachiocephalic vein
93
describe the lymphatic drainage of the larynx superior and inferior to the glottis
Superior to the glottis: via superior deep cervical lymph nodes
Inferior to the glottis: via inferior deep cervical lymph nodes
94
what is a laryngocoele
a herniation of the saccular mucosa
95
what are symptoms of a laryngocoeal?
hoarseness, stridor and dysphagia.
96
how does endotracheal intubation occur?
they have to carefully thread their tube around the epiglottis and down the cords, avoiding the oesophagus
97
what is the cricoid pressure?
cricoid pressure refers to digital pressure against the cricoid cartilage of the larynx, pushing it backwards with the intention of oesophageal compression against the vertebrae and prevention of passive regurgitation of gastric and oesophageal contents
98
why is the cricoid cartilage used to compress the oesophagus?
bc its the only complete ring shaped cartilage in the respiratory tract
