Larynx Flashcards
1
Q
The larynx (voice box) is an organ located in the
A
anterior neck. It is a component of the respiratory tract
2
Q
and has several important functions, including
A
phonation, the cough reflex, and protection of the lower respiratory tract.
3
Q
The structure of the larynx is primarily cartilaginous, and is held together by a series of
A
ligaments and membranes.
4
Q
Internally, the laryngeal muscles move components of the larynx for
A
phonation and breathing.
5
Q
The larynx is located in the… suspended from the …
A
The larynx is located in the anterior compartment of the neck, suspended from the hyoid bone,
6
Q
What veterbre does the larynx spread from
A
and spanning between C3 and C6
7
Q
It is covered anteriorly by the what muscles
A
infrahyoid
8
Q
The larynx is laterally by the lobes of what
A
The thyroid gland
9
Q
Posterior to the larynx is the
A
oesophagus
10
Q
The oesophagus is posterior to the larynx this means pressure can be applied to the cricoid cartilage of the larynx to occlude the oesophagus, and thus prevent what
A
regurgitation of gastric contents (known as cricoid pressure or Sellick’s manoeuvre).
11
Q
Anatomically, the internal cavity of the larynx can be divided into three sections:
A
Supraglottis
Glottis
Subglottis
12
Q
Supraglottis lies where
A
From the inferior surface of the epiglottis to the vestibular folds (false vocal cords).
13
Q
what is the Glottis and what does it do
A
Contains vocal cords and 1cm below them. The opening between the vocal cords is known as rima glottidis, the size of which is altered by the muscles of phonation.
14
Q
where does the Subglottis lie
A
From inferior border of the glottis to the inferior border of the cricoid cartilage
15
Q
The interior surface of the larynx is lined by …. what is the exception
A
pseudostratified ciliated columnar epithelium.
An important exception to this is the true vocal cords, which are lined by a stratified squamous epithelium.
16
Q
The arterial supply to the larynx is via
A
the superior and inferior laryngeal arteries
17
Q
Superior laryngeal artery
A
a branch of the superior thyroid artery (derived from the external carotid).
It follows the internal branch of the superior laryngeal nerve into the larynx.
18
Q
Inferior laryngeal artery
A
a branch of the inferior thyroid artery (derived from the thyrocervical trunk). It follows the recurrent laryngeal nerve into the larynx.
19
Q
Venous drainage is by the
A
superior and inferior laryngeal veins.
20
Q
The superior laryngeal vein drains to the
A
internal jugular vein via the superior thyroid
21
Q
whereas the inferior laryngeal vein drains to
A
the left brachiocephalic vein via the inferior thyroid vein.
22
Q
The larynx receives both motor and sensory innervation via branches of the vagus nerve
A
Recurrent laryngeal nerve
Superior laryngeal nerve
23
Q
Recurrent laryngeal nerve innervates where
A
provides sensory innervation to the infraglottis, and motor innervation to all the internal muscles of larynx (except the cricothyroid)
24
Q
Superior laryngeal nerve innervates where
A
the internal branch provides sensory innervation to the supraglottis, and the external branch provides motor innervation to the cricothyroid muscle.
1
25
The vocal cords are responsible for the production of speech. Their movement is controlled by
the intrinsic muscles of the larynx – the majority of which are innervated by the recurrent laryngeal nerve (an exception is the cricothyroid muscle; innervated by the external laryngeal nerve).
26
What are the majority of the intrinsic muscles of the larynx innervated by
– the majority of which are innervated by the recurrent laryngeal nerve (an exception is the cricothyroid muscle; innervated by the external laryngeal nerve).
27
In unilateral RLN palsy, one vocal cord is paralysed. The other vocal cord tends to compensate, and speech is not affected to a great degree, although the patient may experience
hoarseness of voice
28
In cases of bilateral palsy, both vocal cords are paralysed in a position between adduction and abduction
What does this mean
Breathing is impaired, and phonation cannot occur.
29
In situations where the nerves are only partially damaged, the vocal folds become paralysed in what position
in a fully adducted position
30
In situations where the nerves are only partially damaged, the vocal folds become paralysed in a fully adducted position
What happens if this occurs bilaterally
If this occurs bilaterally, the rima glottidis (space between the vocal cords) is completely closed, and emergency surgical intervention is required to restore the airway.
31
There are how many cartilages, paired and unpaired, located within the larynx
9 total
6 paired
3 unpaired
32
The three unpaired cartilages are the
epiglottis, thyroid and cricoid cartilages.
33
The thyroid cartilage is a large, prominent structure which is easily visible in adult males. It is composed of two sheets (laminae), which join together anteriorly to form
the laryngeal prominence (Adam’s apple).
34
The posterior border of each sheet (of the thyroid gland) project superiorly and inferiorly to form
the superior and inferior horns (also known as cornu).
35
The superior horns are connected to the hyoid bone via
the lateral thyrohyoid ligament,
36
while the inferior horns articulate with the
cricoid cartilage.
37
The cricoid cartilage is
complete ring of hyaline cartilage, consisting of a broad sheet posteriorly and a much narrower arch anteriorly (said to resemble a signet ring in shape).
38
The cricoid cartilage completely encircles the airway, marking the inferior border of the larynx at the level of
C6
39
It articulates with the paired what cartilages posteriorly
| as well as providing an attachment for ...
arytenoid cartilages
as well as providing an attachment for the inferior horns of the thyroid cartilage.
40
What is th only complete ring of cartilage in the larynx or trachea
the cricoid
41
The epiglottis is a leaf shaped plate of what kind of cartilage
elastic
42
The epiglottis marks the entrance of what
which marks the entrance to the larynx
43
Its ‘stalk’ is attached to the back of
the anterior aspect of the thyroid cartilage
44
During swallowing, the epiglottis flattens and moves posteriorly to
close off the larynx and prevent aspiration.
45
There are three paired cartilages..
| where are they situated
the arytenoid, corniculate and cuneiform
| situated bilaterally in the larynx.
46
The arytenoid cartilages are what shape and where do they sit
The arytenoid cartilages are pyramidal shaped structures that sit on the cricoid cartilage.
47
What do the arytenoid cartilages consist of
They consist of an apex, base, three sides and two processes, and provides an attachment point for various key structures in the larynx:
48
Apex
articulates with the corniculate cartilage.
49
Base
articulates with the superior border of the cricoid cartilage.
50
Vocal process
provides attachment for the vocal ligament.
51
Muscular process
provides attachment for the posterior and lateral cricoarytenoid muscles.
52
The corniculate cartilages are..
| what do they articulate with
They articulate with the apices of the arytenoid cartilages.
53
The cuneiform cartilages are located
| what are they attached to and what is their purpose
within the ary-epiglottic folds
| They have no direct attachment, but act to strengthen the folds.
54
the larynx contains numerous ligaments and folds; the ligaments
support the cartilaginous skeleton of the larynx
55
the larynx folds are involved in
airway protection and phonation.
56
he extrinsic ligaments act to attach the components of the larynx to external structures e.g
the hyoid and the cricoid cartilage
57
The intrinsic ligaments are responsible for holding
the cartilages of the larynx together as one functional unit internally
58
Thyrohyoid membrane – Spans between
the superior aspect of the thyroid cartilage and the hyoid bone. It is pierced laterally by the superior laryngeal vessels and internal laryngeal nerve (branch of the superior laryngeal nerve).
59
Median thyrohyoid ligament
Anteromedial thickening of the membrane
60
Lateral thyrohyoid ligaments
Posterolateral thickenings of the membrane.
61
Hyo-epiglottic ligament
Connects the hyoid bone to the anterior aspect of the epiglottis.
62
Cricotracheal ligament
Connects the cricoid cartilage to the trachea.
63
Median cricothyroid ligament
Anteromedial thickening of the cricothyroid ligament (see below), connecting the thyroid and cricoid cartilages.
64
what is the Intrinsic membrane and ligament
Cricothyroid ligament and Quadrangular membrane
65
Cricothyroid ligament – Originates from where and attaches to where
Originates from the cricoid cartilage and extends superiorly, where it terminates with an free (unattached) upper margin – which forms the vocal ligament. It is additionally attached anteriorly to the thyroid cartilage, and posteriorly to the arytenoid cartilage.
66
Quadrangular membrane – Spans between what
Spans between the anterolateral arytenoid cartilage and the lateral aspect of the epiglottis. It has a free upper margin and lower margin. The lower margin is thickened to become the vestibular ligament.
67
what is A cricothyroidotomy and how is it carried out
A cricothyroidotomy is an emergency procedure to provide a temporary airway. It is typically used in situations where there is an obstruction at or above the larynx (e.g foreign body, angioedema or facial trauma), and intubation has been unsuccessful.
To perform the technique, the thyroid cartilage is palpated in the neck – below which there is a depression representing the cricothyroid ligament. A small incision is made in the midline of this ligament, and an endotracheal tube is inserted to secure the airway.
68
There are two important soft tissue folds located within the larynx –
the vestibular folds and
vocal folds.
They play a crucial role in protection of the airway, breathing, and phonation.
69
Which are the more important of the two sets of folds in the larynx
the vocal folds (true vocal cords) are the more important of the two sets. Under the control of the muscles of phonation, they are abducted, adducted, relaxed and tensed to control the pitch of the sound created.
70
What histologically are the vocal chords lined with and why
Non-keratinised stratified squamous epithelium – Stratified layer provides extensive protection against foreign bodies which may accidentally enter the larynx.
71
What is Reinke's space and whats is purpose
Reinke’s space – This watery, amorphous layer is rich in glycosaminoglycans. Due to its fluidity, the epithelium is able to vibrate freely above it to create sound.
72
Where does the vocal ligament lie
Vocal ligament – Lies at the free upper edge of the cricothryoid ligament.
73
where does the vocals muscle lie
Vocalis muscle – Exceptionally fine muscle fibres that lie lateral to the vocal ligaments.
74
How are the vocal fold histologically structured: (superficial to deep):
1 Non-keratinised stratified squamous epithelium
2 Reinke’s space
3 Vocal ligament
4 Vocalis muscle
75
The vocal folds are relatively avascular, and appear white in colour. The space between the vocal folds is known as the
rima glottidis.
76
The vestibular folds (false vocal cords) lie ..
superiorly to the true vocal cords.
77
what do the vestibular folds consist of and what do they do
They consist of the vestibular ligament (free lower edge of the quadrangular membrane) covered by a mucous membrane, and are pink in colour. They are fixed folds, which act to provide protection to the larynx.
78
The muscles of the larynx can be divided into two groups:
| What do each do?
the external muscles and the internal muscles.
The external muscles act to elevate or depress the larynx during swallowing.
In contrast, the internal muscles act to move the individual components of the larynx – playing a vital role in breathing and phonation.
79
The extrinsic muscles act to move the larynx superiorly and inferiorly. They are comprised what groups
the suprahyoid and infrahyoid groups, and the stylopharyngeus (a muscle of the pharynx).
80
The supra- and infrahyoid muscle groups attach to the
hyoid bone
81
How is the hyoid bone bound to the larynx
by strong ligaments; allowing the whole of the larynx to be moved as one unit.
82
As a general rule, the suprahyoid muscles and the stylopharyngeus do WHAT to the larynx
elevate it
83
whilst the infra hyoid muscles do what to the larynx
depress
84
The intrinsic laryngeal muscles act on the individual components of the larynx. They control the shape of the... and the
rima glottidis
and the length and tension of the vocal folds.
85
What is the rima glottidis
opening between the vocal folds and the arytenoid cartilages
86
All the intrinsic muscles of the larynx (except the cricothyroid) are innervated by the
inferior laryngeal nerve
87
how is the inferior laryngeal nerve related to the recurrent laryngeal
it is the terminal branch of the recurrent laryngeal nerve, itself a branch of the vagus nerve
88
he cricothyroid is innervated by the
EXTERNAL BRANCH of the superior laryngeal nerve – again derived from the vagus nerve.
89
The cricothyroid muscle does what
stretches and tenses the vocal ligaments, and so is important for the creation of forceful speech. It also has a role in altering the tone of voice (along with the thyroarytenoid muscle), hence its colloquial name ‘singer’s muscle’.
90
Attachments of the cricothyroid muscle
Originates from the anterolateral aspect of the cricoid cartilage, and attaches to the inferior margin and inferior horn of the thyroid cartilage.
91
Actions of the cricothyroid muscle
Stretches and tenses the vocal ligament.
92
innervation of the cricothyroid muscle
External laryngeal nerve (branch of superior laryngeal).
93
The thyroarytenoid muscle acts to
relax the vocal ligament, allowing for a softer voice.
94
Attachments of The thyroarytenoid
Originates from the inferoposterior aspect of the angle of the thyroid cartilage, and attaches to the anterolateral part of the arytenoid cartilage.
95
Actions of The thyroarytenoid
Relaxes the vocal ligament.
96
innervation of The thyroarytenoid
Inferior laryngeal nerve (branch of recurrent laryngeal).
97
The posterior cricoarytenoid muscles are the sole WHAT of the vocal folds, and thus the only muscle capable of widening the rima glottidis.
abductors
98
Attachments of Posterior cricoarytenoid
Originates from the posterior surface of the cricoid cartilage, and attaches to the muscular process of the arytenoid cartilage.
99
Actions of the Posterior cricoarytenoid
Abducts vocal folds.
100
Innovation of the Posterior cricoarytenoid
Inferior laryngeal nerve (branch of recurrent laryngeal).
101
The lateral cricoarytenoid muscles are the major adductors of the WHAT.
What dies this do to the rima glottidis, modulating the tone and volume of speech.
Vocal chords
Narrows
102
attachments of the Lateral cricoarytenoid
Originates from the arch of the cricoid cartilage, and attaches to the muscular process of the arytenoid cartilage.
103
Actions of the Lateral cricoarytenoid
Adducts the vocal folds.
104
innervation of the Lateral cricoarytenoid
Inferior laryngeal nerve (branch of recurrent laryngeal).
105
The transverse and oblique arytenoids muscles adduct the arytenoid cartilages, closing the posterior portion of the what? and therfore doing what
rima glottidis.
| This narrows the laryngeal inlet.
106
Attachments of the Transverse and Oblique Arytenoids
Spans from one arytenoid cartilage to the opposite arytenoid.
107
Actions of the Transverse and Oblique Arytenoids
Adducts the arytenoid cartilages.
108
innovation of the Transverse and Oblique Arytenoids
Inferior laryngeal nerve (branch of recurrent laryngeal).
109
Which structure stops liquid refluxing into the back of the nose during swallowing?
The soft palate.
110
Which nerve carries sensation from the larynx below the vocal cords?
The recurrent laryngeal nerves.
111
Describe the histology of the mucosa of the trachea?
Simple, columnar, pseudostatified, ciliated with goblet cells
112
Which nerve travels through the parotid gland?
The facial nerve (cranial nerve VII)
113
Where do the parotid and submandibular ducts enter the mouth?
Parotid; from the cheek adjacent to the second upper premolar Submandibular; under the tongue.
114
Which nerve supplies the muscles of the tongue?
The hypoglossal nerve (cranial nerve XII)
115
Order of the nerves from the anterior tongue to posterior tongue to epiglottis and down
Trigeminal (general of anterior tongue), facial (special of anterior tongue) , hypoglossal (general and special innervation of the posterior tongue), superior laryngeal nerve (from epiglottis to vocal chords i think lol) then recurrent laryngeal down trachea
