3. ļ It is the part of respiratory
tract containing the vocal
cords.
ļ A tube-shaped organ.
ļ 2-inch-long
ļ It opens into the laryngeal
part of the pharynx above.
ļ It is continuous below with
the trachea.
ļ It is functioning in:
ļ§ Deglutition (swallowing).
ļ§ Respiration (breathing).
ļ§ Phonation (phonation).
4. ļ½ The larynx is related to
major critical structures
in the neck:
ļ§ Carotid arteries ,
jugular veins, and
vagus nerve.
ļ§ Superior and inferior
thyroid arteries.
ļ§ Superior and recurrent
laryngeal nerves.
5. ļ½ The larynx consists
of four basic
components:
1. A cartilaginous
skeleton.
2. Membranes and
ligaments.
3. Muscles
(intrinsic and
extrinsic).
4. Mucosal lining.
6. ļ½ The cartilaginous skeleton is
comprised of :
1. Thyroid.
2. Cricoid.
Single
3. Epiglottis.
4. Arytenoid.
5. Corniculate. Paired
6. Cuneiform.
ļ½ All the cartilages are hyaline ,
except the epiglottis.
ļ½ Epiglottis is formed of elastic
cartilage.
ļ½ The cartilages are:
ļ§ Connected by joints,
ligaments & membranes.
ļ§ Moved by muscles.
1
3
2
2
3
1 44
5
6
7. 1. Thyrohyoid
membrane, (one
median & two lateral
thyrohyoid
ligaments).
2. Median
cricothyroid
ligament.
3. Cricotracheal
membrane.
4. Hyoepiglottic
ligament.
5. Thyroepiglottic
ligament.
8. ļ½ QuadrangularQuadrangular
membrane:membrane:
ā¢ Extends between the
epiglottis and the
arytenoid cartilages.
ā¢ Its lower free margin
forms the vestibular
ligament that lies
within the vestibular
fold.
ļ½ CricothyroidCricothyroid
membrane (conusmembrane (conus
elasticus):elasticus):
ā¢ Attached to upper
border of the cricoid
cartilage.
ā¢ Its upper free margin
forms vocal
ligament.
9. ļ½ It is the upper opening of the
larynx.
ļ½ It is directed upward and
backward and opens into
the laryngeal part of the
pharynx.
ļ½ Bounded by:
ā¢ Anteriorly: by the upper
margin of epiglottis (E).
ā¢ Posteriorly & below by
arytenoid cartilages (A)
ā¢ Laterally by aryepiglottic
folds (AEF)
ā¢ Piriform fossa: The area of the
pharynx that surrounds the
inlet of larynx.
E
AEF
A
10. ļ½ Extends from laryngeal inlet to the
lower border of the cricoid cartilage.
ļ½ NarrowNarrow in the region of the vestibular
folds (rima vestibuli).
ļ½ NarrowestNarrowest in the region of the vocal
folds (rima glottidis).
ļ½ Divided into three parts:
A. Supraglottic part, the part above
the vestibular folds, is called the
vestibule.
B. Ventricle: The part between the
vestibular & the vocal folds.
C. Infraglottic part, the part below the
vocal folds.
Rima
vestibuli
Rima
glottidis
B
A
C
A
B
C
11. Mucous MembraneMucous Membrane
ļ½ The cavity is lined with
ciliated columnar
epithelium
ļ½ The surface of vocal
folds, is covered with
stratified squamous
epithelium because of
exposure to continuous
trauma during phonation,
ļ½ Contains many mucous
glands, more numerous
in the saccule (for
lubrication of vocal folds)
Muscles
Divided into two groups:
ā¢ Extrinsic musclesExtrinsic muscles:: divided
into two groups
ā¢ Elevators of the larynx
ā¢ Depressors of the larynx
ā¢ Intrinsic musclesIntrinsic muscles:: divided
into two groups
ā¢ Muscles controlling
the laryngeal inlet
ā¢ Muscles controlling
the movements of
the vocal cords
12. Elevators of the Larynx
ļ½ The SuprahyoidThe Suprahyoid
Muscles:Muscles:
1. Digastric.
2. Stylohyoid.
3. Mylohyoid.
4. Geniohyoid.
ļ½ The LongitudinalThe Longitudinal
Muscles of the Pharynx:Muscles of the Pharynx:
1. Stylopharyngeus.
2. Salpingo-pharyngeus.
3. Palatopharyngeus.
Depressors of Larynx
ļ½ The Infrahyoid Muscles:The Infrahyoid Muscles:
1. Sternohyoid.
2. Sternothyroid.
3. Omohyoid.
14. ļ½ Muscle decreasing the
Length & Tension of
Vocal Cords
ā¢ Thyroarytenoid (vocalis)
ā¢ Muscle increasing the
Length & Tension of Vocal
Cords
ā¢ Cricothyroid: It is the only
intrinsic muscle that
present in the outer surface
of the larynx.
15. ā¢ Movements of the
Vocal Cords
Adductio
n
Abduction
Adductors
ā¢ Lateral cricoarytenoid
ā¢ Transverse arytenoid
Abductor
ā¢ Posterior cricoarytenoid
16. Blood Supply
ļ½ Arteries:
ļ§ Upper half: Superior
laryngeal artery, branch of
superior thyroid artery.
ļ§ Lower half: Inferior
laryngeal artery, branch of
inferior thyroid artery.
ļ½ Veins:
ļ§ Accompany the
corresponding arterie.s
ļ½ Lymphatics:
ļ§ The lymph vessels drain
into the deep cervical
lymph nodes.
Nerve Supply
ā¢ Sensory
ļ§ Above the vocal cords:
Internal laryngeal nerve,
branch of the superior
laryngeal of vagus.
ļ§ Below the vocal cords:
Recurrent laryngeal, of
vagus.
ā¢ Motor
ļ§ All intrinsic muscles of
the larynx are supplied by
the recurrent laryngeal
except cricothyroid, which
is supplied by the the
external laryngeal of
superior laryngeal of
vagus.
17.
18. ļ½ Mobile, fibrocartilginous tube, 5
inches long, 1 inch in diameter.
ļ½ Begins: In the neck below the
cricoid cartilage of the larynx (at the
level of C6).
ļ½ Ends: below in the thorax at the
level of sternal anglesternal angle (lower border
of T4), by dividing into right and
left principal (main, primary)
bronchi.
ļ½ The ridge at the bifurcation is called
carina. It is the most sensitive part of
the tract and is associated with the
cough reflex.
19. PosteriorPosterior
ļ½ Esophagus.
ļ½ Left recurrent
laryngeal nerve.
AnteriorAnterior
ā¢ Sternum.
ā¢ Thymus.
ā¢ Left brachiocephalic
vein.
ā¢ Brachiocephalic
artery.
ā¢ Left common carotid
a.
ā¢ Arch of aorta.
Left sideLeft side
ā¢ Arch of aorta.
ā¢ Left common
carotid artery.
ā¢ Left subclavian
a.
ā¢ Left vagus & left
phrenic nerves.
ā¢ Pleura.
Right sideRight side
ā¢ Azygos vein.
ā¢ Right vagus
nerve.
ā¢ Pleura.
20. Nerve SupplyNerve Supply
ļ½ Branches of vagus and the
recurrent laryngeal nerves.
(from vagus) supply
sensory fibers to the
mucous membrane.
ļ½ Branches from the
sympathetic trunks supply
the trachealis muscle and
the blood vessels.
Blood SupplyBlood Supply
ā¢ Arteries: Branches from
the inferior thyroid and
bronchial arteries.
ā¢ Veins: Drain to inferior
thyroid veins.
Lymphatic DrainageLymphatic Drainage
ā¢ Into the pre- &
paratracheal lymph nodes.
21. ļ½ What are Bronchi
ļ½ Bronchi, branching from theĀ trachea, are the
primary passageway for air to get into theĀ lungsĀ [1]
.
It is the plural for bronchus. Each bronchus further
branches into smaller tubes orĀ bronchioles.
ļ½ How Many Primary Bronchi are There
ļ½ There are two primary (extrapulmonary) bronchi
āĀ the right and left main bronchi that connect
theĀ tracheaĀ to the twoĀ lungsĀ .
22. ļ½ The bronchi are located in the thoracic
cavityĀ [3]
Ā along with the trachea and lungs. It
originates from the lower end of the trachea or
windpipe, where it divides or bifurcates (at the
point of carina) into the left and right bronchusĀ .
ļ½
23. ļ½ Right Main (Primary) Bronchus
ļ½ The branch that leads into the right lung is called the right main
or primary bronchusĀ [5]
. Being about 2.5cm long, it is shorter than
the left primary bronchus, but wider in diameterĀ [6]
. It enters the
right lung at around the level where the fifth thoracic vertebra is
located.
ļ½ Divisions and Anatomy
ļ½ The right primary bronchi branches into threeĀ secondary or
lobar bronchi, the superior (upper), middle, and inferior (lower)
lobar bronchi. The right superior secondary bronchus is also
known as the eparterial bronchus because it is the only bronchial
tube originating above the pulmonary arteryās levelĀ [34]
. Bronchial
lymph nodes are located at the origin point of each of the lobar
bronchiĀ [35]
.
ļ½ The main bronchus first divides into the right superior lobar
bronchus and bronchus intermedius, with the latter then giving
rise to the middle and inferior bronchiĀ [4]
.
24. ļ½ The secondary bronchi then further subdivide into
tenĀ tertiary or segmental bronchi.Ā [7]
.
ļ½ These tertiary bronchi then give rise to
theĀ subsegmental bronchi, which then leads to
the smallest branches of a bronchus,
theĀ bronchioles[1]
.
ļ½ The azygos vein overarches the right primary
bronchus from behind, at the base of the lungĀ [8]
.
25. ļ½ Left Main (Primary) Bronchus
ļ½ The left primary bronchus supplies air to the left
lungĀ [9]
Ā and is around 5cm in size, twice as long as the
right main bronchusĀ [10]
. It enters the left lung at around
the level of the sixth thoracic vertebra, passes from
beneath the aortic arch, crossing the esophagus,
thoracic duct, and descending aorta from the frontĀ [1]
.
ļ½ Divisions and Anatomy
ļ½ Like the right main bronchus, the left one also divides
into twoĀ lobar bronchi, the superior and inferior lobar
bronchiĀ [11]
.
ļ½ The lobar bronchi then subdivide into eightĀ tertiary
or segmental bronchiĀ [9, 12]
.
ļ½ The tertiary bronchi continue to divide into smaller
tubes to becomeĀ subsegmental bronchiĀ and
thenĀ bronchioles
26. ļ½ Bronchi Function in the Respiratory System
ļ½ What Does the Primary Bronchi Do
ļ½ The main function of the primary bronchi is to carry
oxygen-rich air reach the lungs during inhalation and
let carbon dioxide-rich air out of the lungs and into the
trachea on its way out during exhalationĀ [17]
. It is the
connection between the rest of the respiratory tract
and the lungs.
ļ½ Its cartilaginous walls help in maintaining its shape
during breathing, preventing it from collapsing, while
the mucus lining, along with cilia keeps any foreign
particles (like dust) from entering the lungsĀ [18]
.
ļ½ The smaller tubes of bronchi are assigned to supply
specific regions within the lungs.
27. ļ½ Secondary Bronchi Function
ļ½ The three secondary or lobar bronchi of the right lung
act as the passage for air to the superior, middle, and
inferiorĀ lobesĀ of the right lung. There are only two
secondary bronchi in the left lung as there are only
two lobes to supply, the superior and inferior lobesĀ [11]
.
ļ½ Tertiary Bronchi Function
ļ½ These supply air to the bronchopulmonary segments.
There are ten bronchopulmonary segments in the right
lung, so it has ten tertiary bronchiĀ [19]
, while the left lung
has eight tertiary bronchi to serve each of its eight
bronchopulmonary segments.
28. ļ½ Associated Health Conditions
ļ½ Bronchitis:Ā Inflammation of the bronchial tube linings,
bronchitis can be either acute or chronic with symptoms
including a cough, shortness of breath, wheezing, and fatigue.
Severe symptoms along with chest pain and high fever may
even indicate pneumoniaĀ [36]
. Bronchitis may occur after severe
flu, or due to excessive smoking and certain environmental
factorsĀ [21]
. The acute form usually goes away on its own after a
few days, which severe or chronic cases may need medications
and breathing exercises along with a healthy lifestyleĀ [22]
.
ļ½ Bronchiectasis:Ā Characterized by chronic dilation of the
bronchi and bronchioles which leads to excessive mucus
discharge, increasing the risks of serious lung infections.
Persistent cough, phlegm discharge, and breathlessness are the
common symptoms of this conditionĀ [23]
. Treatment involves
medication, breathing exercises and special devices for getting
rid of the excess mucus and managing the bronchial dilation,
while an infection may require antibioticsĀ [24]
.
29. ļ½ Asthma:Ā A common condition primarily affecting the smaller tubes of bronchi, it
is characterized by breathing difficulty, wheezing, and a tightness in the chestĀ [30]
.
It causes the smooth muscles to contract, narrowing the airways (bronchial
spasms)Ā [31]
, and leading to the symptoms. Treatment and management include
inhalers and medications to open up the airways, as well as avoiding the
triggers, including smoking, eating certain foods, and going near allergenic
animalsĀ [32]
.
ļ½ Tuberculosis:Ā A bacterial condition that usually affects the lungs, tuberculosis
may also occur in the bronchi and trachea in some cases, leading to fatigue,
fever, cough, and bleeding from the bronchi and tracheaĀ [25]
.
ļ½ Cancers:Ā Lung cancer and bronchial adenoma are two of the cancer types that
may affect the bronchial tubes. There may be different types depending on
origin and growth of the tumor, including bronchogenic carcinoma (originates in
the bronchi or bronchiole epithelium)Ā [26]
and adenoid cystic carcinoma (arising
from salivary glands in the throat and mouth)Ā [27]
. Diagnosis involves various
medical procedures like a CT scan, MRI, bronchoscopy, and biopsyĀ [28]
. Surgical
repair of the affected bronchus (bronchoplasty)Ā [29]
Ā may be considered in some
cases.
30.
31. Right Principal Bronchus
ļ½ About one inch long
ļ½ Wider, shorter and more vertical than
the left ( foreign bodies).
ļ½ Gives superior lobar bronchus before
entering the hilum of the right lung
ļ½ On entering the hilum it divides into
middle and inferior lobar bronchi
Left Principal Bronchus
ā¢ About two inches long
ā¢ Narrower, longer and more horizontal than the right
ā¢ Passes to the left below the arch of aorta and in front of
esophagus
ā¢ On entering the hilum of the left lung it divides into superior
and inferior lobar bronchi
32.
33. Conduction zoneConduction zone
branchesbranches
ļ½ Primary (main)
bronchi
ļ½ Secondary (lobar)
bronchi
ļ½ Tertiary (segmental)
bronchi (supply the
bronchopulmonary
segment)
ļ½ Smaller bronchi
ļ½ Bronchioles
ļ½ Terminal bronchioles
ā¢ Within the lung each
bronchus divides into
number of branches that
can be divided into two
groups:
RespiratoryRespiratory
zonezone
branchesbranches
ā¢ Respiratory
bronchioles
ā¢ Alveolar ducts
ā¢ Alveolar sacs
ā¢ Alveoli