2. INTRODUCTION
Voice box
Organ for phonation or production of voice
Air passage
Also acts as a sphincter at inlet of lower respiratory passages
Well developed in humans
5. DEVELOPMENT OF LARYNX
• The development of the larynx can be divided into prenatal and
postnatal stages.
• At birth, the larynx is located high in the neck between the C1 and
C4 vertebrae, allowing concurrent breathing or vocalization and
deglutition.
• By age 2 years, the larynx descends inferiorly; by age 6 years, it
reaches the adult position between C4 and C7 vertebrae. This new
position provides a greater range of phonation (because of the wider
supraglottic pharynx) at the expense of losing this separation of
function, i.e., deglutition and breathing
6. DEVELOPMENT OF LARYNX
• The larynx grows rapidly during the first 3 years of life, while the
arytenoids remain approximately the same size.
• Beginning at age 18-24 months, the larynx descends in the neck to
achieve its final position at vertebrae C4-C7 by age 6 years.
• The larynx elongates as the hyoid, thyroid, and cricoid cartilages separate
from each other
• The cricoid cartilage continues to develop during the first decade of life,
gradually changing from a funnel shape to a wider adult lumen; therefore,
it is no longer the narrowest portion of the upper airway.
7. SITUATION AND EXTENT
Lies in ant. Midline of neck
Extending from root of the tongue to the trachea
Lies between C3-C6
8. SIZE
Male - 44mm
Female - 36mm
In puberty, male larynx grows rapidly and
becomes larger than female larynx.
9. CONSTITUTION OF LARYNX
Made up of skeletal framework of cartilages
Cartilages joined by joints, ligaments and membranes
11. THYROID CARTILAGE
• V shaped cartilage in cross section
• Consist of right and left laminae
• Ant. Borders of these laminae approach each other at an angle
about 90 degrees in males and 120 degrees in females
12. CRICOIDE CARTILAGE
• Shaped like a ring
• Encircles the larynx below the thyroid cartilage
• Thicker and stronger than thyroid cartilage
• Ring has narrow ant. Part arch, and broad post. lamina
13. EPIGLOTTIC CARTILAGE/EPIGLOTTIS
• Leaf shaped
• Placed in ant wall of upper part of larynx
• Upper end is broad and free, projects upwards behind
the hyoid bone and the tongue.
• Lower end is pointed and attached to the upper part of
the angel between the two laminae of thyroid cartilage.
• The epiglottis is bound by mucous folds and by
ligaments to the back of the tongue, to the side wall of
the pharynx, to the hyoid bone, and to the thyroid
cartilage
14. EPIGLOTTIC CARTILAGE/EPIGLOTTIS
Hyoepiglottic ligament
Short, broad band of loose fibroelastic tissue which connects the
epiglottic cartilage to the upper border of the body of the hyoid bone.
Thyroepiglottic ligament
Strong, elastic and thick, and attaches the lower end of the
thyroid cartilage a little below the median notch.
15. ARYTENOID CARTILAGE
• The arytenoid cartilages are pyramidal shaped
structures that sit on the cricoid cartilage.
• They consist of an apex, base, three sides and two
processes
• Apex –curved & articulates with the corniculate
cartilage.
• Base – concave articulates with the superior border of
the cricoid cartilage.
• Vocal process – provides attachment for the vocal
ligament.
• Muscular process – provides attachment for the
posterior and lateral cricoarytenoid muscles.
18. LARYNGEAL JOINTS
• Cricoarytenoid Joint
• Cricothyroid joint
The two sets of paired joints located in the larynx. These
synovial joints act simultaneously to modulate the movements of the
vocal cords.
21. ARTERIO-VENOUS SUPPLY OF LARYNX
• Superior laryngeal artery – a branch of the superior
thyroid artery (derived from the external carotid).
• Inferior laryngeal artery – a branch of the inferior
thyroid artery (derived from the thyrocervical trunk). It
follows the recurrent laryngeal nerve into the larynx.
• Venous drainage
Superior and Inferior laryngeal veins.
22. NERVE SUPPLY OF LARYNX
• Recurrent laryngeal nerve – provides sensory
innervation to the infraglottis, and motor innervation to
all the internal muscles of larynx (except the
cricothyroid).
• Superior laryngeal nerve – the internal branch
provides sensory innervation to the supraglottis, and
the external branch provides motor innervation to the
cricothyroid muscle.
24. CLINICAL ANATOMY OF LARYNX
Laryngitis
Laryngitis is the inflammation of the larynx.
Symptoms
Hoarse voice, pain, and coughing; sometimes, fever.
Laryngoscopy
inspection of base of tongue, epiglottis, aryepiglottic folds, piriform
fossae,vestibular folds and vocal folds
25. • When a foreign body lodges into the larynx, severe productive cough
starts to expel the FB
• Laryngeal CA
• Laryngotomy: Needle inserted in the midline of cricothyroide membrane.
This done as a emergency procedure.
• Tracheostomy: permanent procedure. 2nd to 3rd ring of trachea removed
after incising isthmus.
• Ext. examination of larynx: head flexed in sitting position, examiner
behind & palpates larynx, neck and surrounding structures with the help
of finger tips.
• Recurrent laryngeal nerve : mediastinal tumors may press lt. recurrent
laryngeal nerve which may cause hoarseness of voice.
• Biopsy
• Throat culture
