1. LOWER RESPIRATORY TRACT, ITS CONDUCTING & RESPIRATORY PORTIONS
LOWER RESPIRATORY TRACT, ITS CONDUCTING & RESPIRATORY PORTIONS. LARYNGO-TRACHEO-BRONCHIAL TREE, BRONCHIAL TREES & RESPIRATORY TREES

2. LOWER RESPIRATORY TRACT INCLUDES
Conducting Portion:
Larynx
Trachea
Extrapulmonary bronchi:
Right & Left Main (Principal, Primary, or 1st Order) Bronchi
Intrapulmonary bronchi:
Lobar (Secondary) bronchi:
Segmental (Tertiary) bronchi:
Several consequent subdivisions in each bronchopulmonary segment up to the terminal bronchi
Terminal bronchi (smallest, about 1mm in diameter)
Regular bronchioles
Terminal bronchioles (divide in pulmonary lobules)
Respiratory Portion (respiratory trees or acini)

4. Lower Airway: Laryngo-Tracheo-Bronchial Tree

5. Surface Markings of the Larynx & Thyroid Gland

6. Surface Markings of Laryngeal Structures

7. Examination of the Larynx

8. Larynx, Trachea & Thyroid Gland

9. Position & Relations of the LarynxC1 C2 C3 C4 C5
Larynx C6 C7

10. The Larynx 4
Larynx 5 6

11. The Larynx
It is attached to the Hyoid bone via the Thyrohyoid membrane
It lies level with fourth to sixth cervical vertebrae
Its epiglottis can reach the level of the third cervical vertebra
Average measurements in European adults:
In Males In Females
Length: 44mm 36 mm
Width: 43 mm 41 mm
Ant.-Post. 36 mm 26 mm

12. The Laryngeal Skeleton
The Laryngeal Skeleton consists of the following cartilages (11):
Epiglottis (1)
Thyroid (1)
Cricoid (1)
Arytenoid (2)
Corniculate (2)
Cuneiform (2)
Triticea (2)

13. Laryngeal Skeleton – 3 Views

14. Laryngeal Skeleton – Front View

15. Laryngeal Skeleton from Behind

16. Laryngeal Cartilages
Lamina
Lamina
Arch

17. Epiglottis (from behind)
Apex
Stalk

18. Epiglottis

19. Thyroid Cartilage

20. Thyroid Cartilage – 3 Views
Lamina
Lamina
Front
Back
Side

21. Attachments of Extrinsic Laryngeal Muscles
Lamina

22. Cricoid & Arytenoid Cartilages
Lamina

23. Cricoid & Arytenoid Cartilages

24. Arytenoid Cartilages
Arch

25. Midsagittal View of Laryngeal Skeleton

26. Laryngeal Skeleton from Behind

27. The Laryngeal Membranes & Ligaments
Thyrohyoid Membrane
Between Thyroid cartilage and Hyoid bone
Quadrangular Membrane – on each side of Laryngeal Vestibule
Between lateral border of Epiglottis & front of Arytenoid cartilage
Its lower edge is the Vestibular (false vocal) Ligament
Cricovocal Membrane (Conus Elasticus) is attached:
Below: to upper border of Arch of Cricoid cartilage
Anterosuperiorly: to inner aspect of Laryngeal prominence
Posterosuperiorly: to vocal processes of Arytenoid cartilages
It includes:
Median Cricothyroid Ligament
Lateral Cricothyroid Ligaments (right & left)
Its upper edge is the Vocal (true vocal) ligament

28. Left Cricovocal Membrane & Vocal LigamentOr
Left half of Conus Elasticus

29. Laryngeal Fibroelastic Membranes
Conus Elasticus
Posterosuperior View

30. Laryngeal Cartilages, Membranes & Ligaments
Conus
Elasticus
(Right)
Left
Cricovocal Membrane
(Left)
Posterosuperior View

31. View of Laryngeal Cavity & Membranes
Epiglottis
Thyroid Cartilage
Cricoid Cartilage
Cricovocal Membrane
(left)

32. The Laryngeal Cavity
Laryngeal opening (aditus) and structures that bound it:
Epiglottis (anteriorly)
Aryepiglottic fold (laterally)
Interarytenoid fold (posteriorly)
Laryngeal Vestibule (extends from laryngeal opening to rima vestibularis – an opening between the laryngeal vestibule & ventricles).
Rima Vestibularis is limited by:
2 Vestibular folds or false vocal folds (right & left)
2 Laryngeal Ventricles (right & left) – on each side between vestibular and vocal folds.
Glottis – an area between the Ventricles and Infraglottic Part
It consists of
2 Vocal folds (true vocal fold)
Rima glottidis (or rima vocalis, or vocal fissure) – space between 2 vocal folds
Infraglottic part of laryngeal cavity (between the glottis and the upper end of the trachea)
It communicates with the trachea at the level of C6 vertebra

33. Laryngeal Opening (Inlet)
Epiglottis

34. Piriform Fossa
A small piriform fossa on each side of the Laryngeal Inlet is bounded:
Medially - by the aryepiglottic fold
Laterally by the thyroid cartilage and thyrohyoid membrane.
Beneath its mucous membrane are the branches of the Internal Laryngeal Nerve (branch of Superior Laryngeal Nerve) which have pierced the thyrohyoid membrane.
Foreign bodies (fish bones) may lodge in the fossa and, if the mucous membrane is pierced during their removal, this nerve may be damaged, with consequent anaesthesia of the region including Laryngeal Vestibule

35. Posterior View of Laryngeal Cavity
Vestibule
Infraglottic Part

36. Subdivisions of Laryngeal Cavity

37. Laryngeal Cavity (Coronal section)
View from behind
Vestibule
Left Ventricle
Right Ventricle
Infraglottic
Part

38. Subdivisions of Laryngeal Cavity
Laryngoscopic View of Constricted Part of the Laryngeal Cavity

39. Constricted Part of Laryngeal Cavity

40. The Laryngeal Muscles Extrinsic Muscles: (attached to the larynx)
Sternothyroid
Thyrohyoid
Inferior Pharyngeal Constrictor:
Thyropharyngeus & Cricopharyngeus
Longitudinal fibres of Oesophagus
Intrinsic Muscles :
Cricothyroid
Posterior Crico-arytenoid
Lateral Crico-arytenoid
Transverse Arytenoid
Oblique Arytenoid
Aryepiglottic
Thyro-epiglottic
Thyro-arytenoid
Vocalis

41. The Laryngeal Muscles Muscles which alter the glottis:
Posterior Crico-arytenoid
Lateral Crico-arytenoid
Transverse Arytenoid
Oblique Arytenoid
Muscles regulating tension of vocal ligaments:
Cricothyroid
Vocalis
Thyro-arytenoid
Muscles modifying laryngeal inlet:
Thyro-epiglottic
Aryepiglottic
Abductors of Vocal Ligament:
Adductors of Vocal Ligament:

42. Intrinsic Laryngeal Muscles

43. Intrinsic Laryngeal Muscles

44. Intrinsic Laryngeal Muscles

45. Intrinsic Laryngeal Muscles

46. GLOTTIS Glottis consists of: 2 Vocal Folds, each contains:
Vocal ligament and Vocalis muscle covered by mucosa
Vocal process of Arytenoid cartilage covered by mucosa
Space between 2 Vocal Folds
Intermembranous part (anterior two thirds – 15 mm):
Between two vocal ligaments
Intercartilaginous part (posterior one third – 5 mm)
Between two vocal processes

47. Glottis
Vocal Folds
(without mucosa)
Rima Glottidis
(Vocalis)

48. Rima Glottidis (Vocalis)
Intermembranous
Part
Intercatilaginous
Part
Quiet Respiration
Forced Respiration
Adduction of vocal folds
Closure of rima glottidis
Abduction of vocal folds

49. Functional Postures of Rima Glottidis

50. Actions of Laryngeal Muscles

51. Rima Glottidis in Normal Inspiration & Phonation
Laryngoscopic View
Front
Back

52. Tomographic View of Larynx pronouncing Sound EE
Vestibular Folds
Ventricle
Lamina of
Thyroid
Cartilage
Vocal Folds
Trachea

53. Participation of Larynx in Deglutition

54. Participation of Larynx in Coughing

55. Participation of Larynx in Forced Respiration

56. Participation of Larynx in Phonation

57. Participation of Larynx in Whispering

61. LARYNGEAL RELATIONS Anterior: Posterior:
Skin, superficial fascia, anterior jugular veins, deep fascia, pretracheal fascia
Sternohyoid, Omohyoid, Sternothyroid & Thyrohyoid Muscles
Pyramidal lobe of thyroid gland (often absent)
Posterior:
Laryngopharynx
Upper end of Esophagus (with its first constriction)
Retropharyngeal space
Cervical vertebrae C4 – C6

62. Surface Markings & Relations of the Larynx

63. Laryngeal Relations

64. Laryngeal Relations

65. LARYNGEAL RELATIONS Lateral Inferior pharyngeal constrictors
Branches of Recurrent laryngeal nerves
Upper poles of lobes of thyroid gland & superior parathyroid glands
Superior thyroid arteries and veins
External branches of superior laryngeal nerves
Carotid sheaths & Main neurovascular bundles of the neck:
Common carotid artery
Internal jugular vein
Vagus nerve (X CN)
Ansa cervicalis
Sternocleidomastoid muscles

66. Thyroid & Parathyroid Glands

67. Cricothyrotomy
Cricothyroid Membrane is to be pierced between Thyroid & Cricoid Cartilages

68. CRICOTHYROTOMY

69. Laryngeal Muscles & Nerves

70. The Superior Laryngeal Nerve (Branch of Vagus)
It descends alongside the pharynx, first posterior, then medial to the internal carotid artery, and divides into the internal and external laryngeal nerves
The External Laryngeal Nerve, smaller than the internal laryngeal nerve
It descends posterior to the sternothyroid with the superior thyroid artery but on a deeper plane
It lies at first on the inferior pharyngeal constrictor and then, piercing it, curves round the inferior thyroid tubercle to reach the cricothyroid
It supplies the Cricothyroid Muscle
It also supplies the pharyngeal plexus and inferior pharyngeal constrictor

71. The Internal Laryngeal Nerve
The internal laryngeal nerve is sensory to the laryngeal mucosa down to the level of the vocal folds.
It also carries afferent fibres from the laryngeal neuromuscular spindles and other stretch receptors
It descends to the thyrohyoid membrane, pierces it above the superior laryngeal artery and divides into an upper and lower branch
The upper is horizontal and supplies the mucosa of the pharynx, the epiglottis, vallecula and laryngeal vestibule
The lower descends in the medial wall of the piriform fossa, supplying the aryepiglottic fold, the mucosa on the back of the arytenoid cartilage and one or two branches to the arytenoideus, which unite with twigs from the recurrent laryngeal to supply the same muscle
The internal laryngeal nerve ends by piercing the inferior constrictor muscle to unite with an ascending branch from the recurrent laryngeal nerve

72. The Recurrent Laryngeal Nerve (Branch of Vagus)
On both sides the recurrent laryngeal nerve ascends in or near a groove between the trachea and oesophagus
It is closely related to the medial surface of the thyroid gland before passing under the lower border of the inferior constrictor to enter the larynx behind the articulation of the inferior thyroid cornu with the cricoid cartilage
It supplies all laryngeal muscles, except the cricothyroid
It communicates with the Internal Laryngeal Nerve
It supplies sensory filaments to the laryngeal mucosa below the vocal folds
It also carries afferent fibres from laryngeal stretch receptors.
As it ascends in the neck it supplies branches, more numerous on the left, to the mucosa and tunica muscularis of the oesophagus and trachea and to the inferior constrictor

73. View in Paralysis of Left Vagus
Left side R L

74. Paralysis of Vocal Cords
Normal R L P

75. Surface Markings of Trachea & Bronchi

76. Is a membrano-cartilaginous tube
Trachea:
Is a membrano-cartilaginous tube
Measures about 11 cm in length and its diameter is from 2.0 to 2.5 cm (bigger in male)
Extends from cricoid cartilage of larynx (C6 vertebra) to upper border of fifth thoracic vertebra
Has a cervical part & thoracic part
Plane of the superior thoracic aperture separates this two parts
Divides into two main or principle bronchi (right & left) at the level of sternal angle (level of intervertebral disk between T4 & T5).

77. TRACHEA

78. TRACHEAL WALL Pretracheal fascia
C-shaped hyaline tracheal cartilages (16 – 20)
They measure 4 mm in depth & 1mm in thickness
They are interconnected by Annular (intercartilaginous) ligaments
Posterior fibromuscular wall
Smooth muscle (Trachealis) & Fibrous tissue
Submucosa
Tracheal glands
Mucosa
Blood supply: Inferior thyroid arteries
Nerves: from Vagus and Sympathetic nerves

79. TRACHEAL WALL

80. Parts of Trachea & their Relations
Cervical
Part
Thoracic Part

81. Cervical Part of the Trachea
Larynx
Cervical
Trachea

82. TRACHEAL RELATIONS (Neck)
Anterior:
Isthmus of thyroid gland
Inferior thyroid veins
Thyroidea ima artery
Sternothyroid & sternohyoid muscles
Pretracheal fascia & Pretracheal lymph nodes
Jugular venous arch
Posterior:
Esophagus
Branches of recurrent laryngeal nerves
Branches of inferior thyroid artery

83. TRACHEAL RELATIONS (Neck)
Lateral:
Common carotid arteries
Lobes of thyroid gland
Inferior thyroid arteries
Recurrent laryngeal nerves
Paratracheal lymph nodes

84. Tracheal Relations (Neck)

85. TRACHEAL RELATIONS (Neck)

86. Thoracic Part of the Trachea in Superior Mediastinum

87. TRACHEAL RELATIONS (Thorax)
Anterior:
Manubrium sterni
Thymic lobes
Brachiocephalic trunk
Left common carotid artery
Aortic arch
Deep cardiac nerve plexus
Left brachiocephalic vein
Posterior:
Esophagus

88. TRACHEAL RELATIONS (Thorax)
Lateral: Right side
Pleura and right vagus
Brachiocephalic trunk
Lateral: Left side
Left recurrent laryngeal nerve
Aortic arch, Left common carotid & Subclavian Aa.

89. Tracheal Relations

90. Tracheal Bifurcation
TRACHEA
Left
Right

91. View of Tracheal Bifurcation during Mediastinoscopy

92. Tracheal Bifurcation (View during Tracheoscopy)

93. Tumor on the Left Side of Carina (Tracheoscopy)

94. Principal (Primary, Main) Right & Left Bronchi
Right Bronchus
It is wider, shorter, and more vertical in direction than the left
It is about 2.5 cm. long, and enters the right lung nearly opposite the fifth thoracic vertebra.
The azygos vein arches over it from behind
The right pulmonary artery lies at first below and then in front of it
It divides into:
Eparterial (Superior Lobar) Bronchus
Hyparterial (Intermidiate) Bronchus
Middle Lobar Bronchus
Inferior Lobar Bronchus

95. Tracheal Bifurcation – Differences of Primary Bronchi

96. Principal (Primary, Main) Right & Left Bronchi
Left Bronchus
It is narrower, longer (being nearly 5 cm. long)and less vertical than the right.
It enters the root of the left lung opposite the sixth thoracic vertebra.
It passes beneath the aortic arch, crosses in front of the esophagus, the thoracic duct, and the descending aorta.
It has the left pulmonary artery lying at first above, and then in front of it. Therefore it is Hyparterial
On entering the hilum the left main bronchus divides into:
Superior lobar bronchus
Inferior lobar bronchus

97. Surface Markings of Trachea & Bronchi
Tracheo-Bronchial Tree with Pulmonary Vessels
Tracheo-Bronchial Tree

98. Secondary (Lobar) & Tertiary (Segmental) Bronchi
Intrapulmonary Bronchi of Right Lung:
Superior Lobar Bronchus
Apical (Superior) Segmental Bronchus
Anterior Segmental Bronchus
Posterior Segmental Bronchus
Middle Lobar Bronchus
Medial Segmental Bronchus
Lateral Segmental Bronchus
Inferior Lobar Bronchus
Anterior Basal Segmental Bronchus
Posterior Basal Segmental Bronchus
Lateral Basal Segmental Bronchus
Medial Basal Segmental Bronchus
There are several subsequent subdivisions of bronchi within each bronchopulmonary segment

99. Secondary (Lobar) & Tertiary (Segmental) Bronchi
Intrapulmonary Bronchi of Left Lung:
Superior Lobar Bronchus
Superior Division
Apicoposterior Segmental Bronchus
Anterior Segmental Bronchus
Inferior Division
Superior lingular segmental bronchus
Inferior lingular segmental bronchus
Inferior Lobar Bronchus
Apical (Superior) Segmental Bronchus
Anteriomedial Basal Segmental Bronchus
Posterior Basal Segmental Bronchus
Lateral Basal Segmental Bronchus
There are several subsequent subdivisions of bronchi within each bronchopulmonary segment

100. TRACHEO-BRONCHIAL TREE

101. Tracheo-Bronchial Tree (with lungs)

102. Cast View of Tracheo-Bronchial Tree
Left main bronchus
End of Trachea
Right
main
bronchus
SILICON CAST OF TRACHEO-BRONCHIAL TREE

103. Tracheo-Bronchial Tree (Scheme)

104. The Bronchopulmonary Segment
It is a smaller structural subunit of pulmonary lobe with a distinct base and apex (pointed toward the hilum)
It is made up of the lung parenchyma
It is ventilated by the tertiary (segmental) bronchus, which further ramifies within segment
It is supplied by segmental branch of pulmonary artery (both bronchus & artery enter segment via its apex)
It is separated from the adjacent segments by the intersegmental septa of connective tissue
This septa contain intersegmental veins which drain adjacent segments and serve as guides for thoracic surgeons in removal of pathologically changed segments. That allows a minimal removal of lung tissue.
Each segment contains smaller units:
Pulmonary Lobules
Respiratory Trees (Acini)

105. Bronchopulmonary Segment

106. Tracheobronchial Tree with Segmental Bronchi

107. Right & Left Bronchial Trees & BP Segments
Lateral View of Right Bronchial Tree
Lateral View of Left Bronchial Tree
Apicoposterior
Apical
Posterior
Anterior
Anterior
Superior
Superior Lingular
Superior L
Inferior Lingular M
Posterior
Basal
Lateral
Basal
Anterior
Basal
Medial
Basal
Anteromedial
Basal
Lateral
Basal
Posterior
Basal

108. Segmental Bronchi of Right Lung

109. Segmental Bronchi of Left Lung

110. Bronchial Arteries

111. Bronchial Arteries - Variations

112. Bronchial Veins

113. Bronchioles
Bronchioles – tiny tubes lacking cartilage and cilia; possess smooth muscle
Terminal bronchiole
Smooth muscle
Respiratory bronchiole
Autonomic nervous system regulates diameter of bronchioles
Sympathetic division dilates bronchioles
Parasympathetic division constricts bronchioles

114. RESPIRATORY PORTION OF LOWER AIRWAY
A Respiratory Tree or ACINUS includes:
Respiratory bronchiole (with single alveoli)
Alveolar duct
Alveolar Atrium (Vestibule)
Alveolar sac
Alveoli
Air-blood barriers (respiratory membranes)

115. Respiratory Zone
Alveoli – cup shaped structures at the end of the Respiratory bronchioles that resemble bunches of grapes; are in direct contact with capillaries (gas exchange); covered with SURFACTANT that keep them from collapsing
Respiratory
bronchiole

116. RESPIRATORY TREES

117. Blood Supply of Pulmonary Lobule
Bronchial Artery

118. Blood Supply of Respiratory Zone

119. Alveolar Sacs in Action

120. Lymphatic Drainage of Right Bronchial Tree

121. Lymphatic Drainage of Tracheo-bronchial Tree

122. Clubbing of the Fingernail
The red line shows the outline of a clubbed nail.
Clubbing develops in five steps:
Fluctuation and softening of the nail bed (increased ballotability)
Loss of the normal <165° angle ("Lovibond angle") between the nailbed and the fold (cuticula)
Increased convexity of the nail fold
Thickening of the whole distal finger (resembling a drumstick)
Shiny aspect and striation of the nail and skin

123. Clubbing is associated with:
Lung disease:
Lung cancer
Interstitial lung disease
Tuberculosis
Bronchiectasis
Suppurative lung disease:
lung abscess,
empyema
Cystic fibrosis
Pulmonary hypertension
Mesothelioma
Heart disease:
Any disease featuring chronic hypoxia
Congenital cyanotic heart disease (most common cardiac cause)

124. Clubbing of the Fingernails

125. THANK YOU