1. Anatomy & Physiology of Larynx
Dr. Vishal Sharma

2. Larynx (anterior)

3. Larynx (posterior)

4. Larynx (posterior)

5. Larynx (lateral)

6. Larynx (superior)

7. Larynx (superior)

8. Larynx (sagittal section)

9. Larynx (sagittal section)

10. Larynx (coronal section)

11. Vocal fold

12. Vocal fold

13. Laryngeal Cartilages 3 single & 3 paired Single Paired
Epiglottis Arytenoid
Thyroid Corniculate (Santorini)
Cricoid Cuneiform (Wrisberg)

14. Cartilages (anterior)

15. Laryngeal Cartilages

16. Cartilages (posterior)

17. Cartilages (posterior)

18. Cartilage Histology
Elastic: Epiglottis, corniculate, cuneiform & apex of arytenoid. Little or no calcification.
Hyaline: Thyroid, cricoid & remaining arytenoid. Calcify as age advances. Ossification begins by yr & is completed by 60 yr.

19. Indirect Laryngoscopy

20. Flexible Laryngoscopy
RIGHT
LEFT

21. Laryngeal cavity 1. Laryngeal inlet 2. Laryngeal Vestibule
3. Laryngeal Ventricle
4. Rima glottis
5. Subglottis

22. Pediatric Larynx Conical in shape & subglottis is narrowest part
Positioned high (C3-C4)
Moves higher during swallowing allowing simultaneous breathing & feeding
Loose sub-mucosal tissues (swell up easily)
Soft cartilages that collapse easily

23. Membranes & Ligaments Extrinsic:
connect thyroid cartilage & epiglottis with hyoid bone; cricoid cartilage with trachea.
Intrinsic:
connect cartilages of larynx to each other.

24. Extrinsic Thyrohyoid membrane Hyoepiglottic ligament
Cricotracheal ligament

25. Intrinsic

26. Intrinsic

27. Intrinsic 1. Quadrangular membrane
 Ary-epiglottic ligament  Vestibular ligament
2. Crico-vocal membrane
 Vocal ligament  Cricothyroid membrane
3. Thyro-epiglottic ligament

28. Oncological Divisions
A. Supraglottis: laryngeal inlet to apex of ventricle
B. Glottis: apex of ventricle to 10 mm below
C. Subglottis: lower glottic border to lower cricoid border

29. Subsites A. Supraglottis: 1. Epiglottis 2. Aryepiglottic
folds 3. Ventricular bands 4. Laryngeal
Ventricle
B. Glottis: True vocal cords 2. Anterior
commissure Posterior commissure
C. Subglottis

30. Intrinsic Muscles A. Acting on vocal cords
Abduction   Posterior crico-arytenoideus
Adduction   Lateral crico-arytenoideus
 Transverse inter-arytenoideus
 Thyro-arytenoideus externa
Tension + lengthening   Cricothyroid
Relaxation + shortening   Vocalis

31. Intrinsic Muscles B. Acting on laryngeal inlet
Opener   Thyro-epiglottic
Closer   Oblique inter-arytenoideus
 Ary-epiglottic

32. Extrinsic Muscles Primary Elevators Secondary Elevators
 Stylopharyngeus  Mylohyoid
 Salpingopharyngeus  Stylohyoid
 Palatopharyngeus  Geniohyoid
 Thyrohyoid  Digastric
Depressors
 Sternohyoid  Sternothyroid  Omohyoid

33. Posterior cricoarytenoid

34. Lateral cricoarytenoid

35. Transverse Inter-arytenoid

36. Cricothyroid

37. Thyroarytenoid externa + Vocalis

38. Oblique Inter-arytenoid

41. Spaces of Larynx

42. Reinke’s space

43. Pre-epiglottic space

44. Para-glottic space

45. Communications

46. Shape of Glottis

47. Shape of Glottis
Quiet Respiration
Forced Inspiration

48. Inspiration

49. Shape of Glottis
Normal voice
Whisper

50. Normal phonation

51. Whisper

52. Mucous Membrane Stratified squamous epithelium:
Epiglottis (anterior surface + upper half of posterior surface), upper part of aryepiglottic folds & vocal cords
Pseudo-stratified ciliated columnar (respiratory) epithelium:
Rest of laryngeal mucous membrane

53. Nerve Supply Superior Laryngeal Nerve:
Internal: sensation to supraglottis & glottis
External: motor to cricothyroid muscle
Recurrent Laryngeal Nerve:
sensation to subglottis
motor to all intrinsic muscles but cricothyroid

54. Blood Supply Arterial supply:
Laryngeal br. of superior & inferior thyroid
Venous drainage:
Superior thyroid vein  internal jugular vein
Inferior thyroid vein  innominate vein

55. Lymphatic Drainage
Supraglottis: via thyrohyoid membrane into upper deep cervical nodes & thyroid gland
Subglottis: via cricothyroid membrane into pretracheal + lower deep cervical nodes
Glottis: has no lymphatics

56. Functions of Larynx 1. Protection of lower airway
2. Phonation (voice production)
3. Passage of air into lungs for respiration
4. Chest fixation by glottic closure

57. Protection of lower airway
a. 3-level below-upward closure of:
 vocal cords  ventricular bands
 aryepiglottic folds
b. Cessation of respiration: mediated by glossopharyngeal nv & deglutition centre.
c. Cough reflex

58. Voice Production 1. Voice activating air reservoir in lungs:
affects voice intensity
2. Voice generation: affects voice pitch
3. Voice resonation: affects voice quality
4. Voice articulation: affects voice quality

59. Voice Production

60. Neuro-chronaxic theory (?)
Vibration of vocal fold muscles due to impulses generated from recurrent laryngeal nerves. Speed is regulated by acoustic center in brain.
Obsolete theory because:
muscle contraction not so fast to produce vibrations
even paralyzed vocal folds can produce phonation
passive phonation occurs in excised larynges

61. Combined Aerodynamic & Myoelastic theory
Proposed by Jan Willem van den Berg in 1958
Vocal cords kept approximated  Subglottic blast of air opens vocal cords from below upwards & causes their passive vibration, producing sound  Muscle tension + Bernoulli's effect closes vocal cords below upwards  Cycle repeated

62. Aerodynamic myoelastic theory (opening phase)

63. Aerodynamic myoelastic theory (closing phase)

64. Stroboscopic examination

65. Voice generation  High pitch = short, thin, tense, less
elastic vocal cords
 Low pitch = long, bulky, relaxed, more
 Falsetto voice = tense vocal cords, only edge of vocal fold vibrates & body is relaxed,
with small phonatory gap

66. Falsetto voice

67. Vocal cord cross-section

68. Normal phonation

69. Falsetto voice

70. Glottis state in phonation
Voiceless (full air stream)
Breathy voice (murmur)
Slack voice
Modal voice: maximum vibration, sweet spot
Stiff voice
Creaky voice (restricted air stream)
Glottalized (blocked air stream)

71. Glottis state in phonation

72. Vocal Registers Vocal fry register: lowest vocal register
Modal voice register: commonly used for speaking & singing
Falsetto register: one octave higher than modal
voice register
Whistle register: highest voice register. Used by
female singers

73. Musical notes & octaves

74. Guinness World records
Georgia Brown (2006):
Highest vocal range from G2 to G10
Highest vocal note (G10)
Adam Lopez (2002):
Highest vocal note for male (C8)
Tim Storms (2002):
lowest vocal note (8 Hz = two octaves below lowest B on a piano)

76. Adam Lopez & Tim Storms

77. Voice resonation Oral & pharyngeal cavity  S Nasal cavity  M, N, Ng
In rhinolalia clausa:
M, N & Ng are uttered as B, D & G respectively
In rhinolalia aperta:
B, D & G are uttered as M, N & Ng

78. Organs of articulation

79. Places of articulation
 Bilabial: both lips  Labio-Dental: lips + teeth
 Dental: teeth + tip of tongue
 Alveolar: alveolus + tip of tongue
 Palatal: hard palate + tongue blade
 Retroflex: tongue tip + hard palate
 Velar: tongue base + soft palate
 Glottal: produced in glottis

80. Places of articulation

81. Sound production  Bilabial  P, B, M, W
 Labio-Dental  F, V;  Dental  T, D
 Alveolar  T, D, N, L, S, Z
 Palatal  Ch, Chh, J, Jh, Y
 Retroflex  R, T, Th, D, Dh
 Velar  K, Kh, G, Gh
 Glottal  H, ?, uh-oh

82. Chest fixation
Closure of glottis helps in raising intra-thoracic & intra-abdominal pressure required for:
Coughing  Vomiting
Defecation  Micturition
Climbing  Weight-lifting
Labour

83. Thank You