Brief anatomy of larynx (ENT)

1. By
Jini Abraham

2. Laryngeal cavity is lined by the respiratory
epithelium except the vocal cords and parts
of epiglottis, which is lined by the stratified
squamous epithelium.
The cavity starts at the laryngeal inlet where
it communicates with the pharynx and ends
at the lower border of the cricoid cartilage
where it continues with the lumen of
trachea.

4.  The laryngeal inlet is bounded –
Anteriorly – free margin of epiglottis
Laterally – Aryepiglottic fold
Posteriorly – Interarytenoid fold

5. Laryngeal interior is divided by two folds
into three parts –
Supraglottis
Vestibule
Ventricle
Glottis
Subglottis
DIVISIONS

6. Folds dividing the cavity are –
Vestibular folds –
False vocal cords
Two in number
Each is fold of mucous membrane
extending anteroposteriorly across
laryngeal cavity
Contains vestibular ligament, few fibres
of thyroarytenoideus muscle and mucous
glands

7. Vocal folds –
True vocal cords
Two pearly-white shaped bands
extending from the middle of thyroid
angle to vocal processes of arytenoids
Each vocal cord consists of vocal
ligament

8. Mainly constitutes
–
Epiglottis
Aryepiglottic
folds
Arytenoids
False cords
SUPRAGLOTTIS

9. Extends from laryngeal inlet to vestibular
folds
Anterior wall formed by posterior surface
of epiglottis
Sides by aryepiglottic folds
Posterior wall by mucous membrane over
anterior surface of arytenoids
VESTIBULE

10. Sinus of larynx
Deep elliptical space between vestibular
and vocal folds
VENTRICLE

11. Diverticulum of mucous membrane which
starts from the anterior part of ventricular
cavity and extends upwards between
vestibular folds and lamina of thyroid
cartilage
Laryngocele – air containing sac present in
the neck
Presence of mucous glands
SACCULE OF LARYNX

12. Rima glottidis
Elongated space between vocal cords anteriorly
and vocal processes and arytenoids posteriorly
24mm in men and 16mm in women
Narrowest part of laryngeal cavity
Anterior two-thirds formed by membranous
cords and posterior one-third by vocal processes
of arytenoids
GLOTTIS

13. Size and shape
of glottis varies
with movements
of vocal cords

14. Infraglottic larynx
Extends from vocal cords to lower border
of cricoid cartilage
SUBGLOTTIS