Ligaments of larynx & epiglottis

One to five percent of patients with sarcoidosis present with lesions within the larynx. The epiglottis is the most common site of involvement.

The lingual surface of the epiglottis and the true vocal cords are lined by stratified squamous epithelium. 

Epiglottis has a lingual and laryngeal surface. The laryngeal surface is lined by pseudostratified ciliated columnar epithelium. Beneath this epithelium in the lamina propria on the laryngeal side of the epiglottis, there are abundant tubuloacinar seromucous glands.

Endoscopists are very careful when guiding the endoscope past the epiglottis, which is a pear-shaped portion of elastic cartilage that can be moved during swallowing to close the larynx, preventing swallowed material from eventually entering the lungs.

• The arytenoids are the site of the attachment of the vocal cords  within the larynx.
• The cricoid cartilage is in the more distal portion of the larynx.
• The pharynx is shared by the respiratory and gastrointestinal tracts.

• The thyroid cartilage forms a median elevation, called the laryngeal prominence (“Adam’s apple”), and lies inferior to the hyoid bone.
• The epiglottis is an elastic cartilage, shaped like a spoon, that is posterior to the root of the tongue.
• The cricoid cartilage is shaped like a signet ring, with the broad part of the ring facing posteriorly.
• The arytenoid cartilages are shaped like a pyramid.

Ref: Langman Embryology, 11 Edition, pg. 277

Ans. is ‘c’ i.e., Epiglottis is big & omega shaped

Anatom^y of airway in neonate

The anatomy of the upper airway predisposes to obstruction. Its characteristic features are

o Proportionately larger head and tongue, the tongue is often pushed against the palate

o Narrow nasal passages

o Anterior and cephalad larynx (the larynx is anteriorly inclined)

o Epiglottis is soft, large and patulous, Omega shaped and inclined at 45°.

• The Subglottic region rather than the rima glottidis is the narrowest portion of the airway.
• Vocal cord is at the level of C,
• Trachea bifurcates at the level of T2

o Larynx lies opposite Pd, 3′^d and 4^th cervical vertebra at birth.

Infant’s Larynx Differs from Adult in:

1. It is situated high up (C2 – C4).° (in adults = C3 – C6)

2. Of equal size in both sixes (in adults it is larger in males)

3. Larynx is funnel shaped

4. The narrowest part of the infantile larynx is the junction of subglottic larynx with trachea and this is because cricoid cartilage is very small

5. Cartilages:

1. Epiglottis is omega shaped, soft, large and patulous.
2. Laryngeal cartilages are soft and collapse easily
3. Thyroid cartilage is flat
4. Arytenoid cartilage is relatively large

6. The cricothyroid and thyrohyoid spaces are narrow

7. The submucosal tissue is thick and loose and becomes oedematous in response to inflammation

8. Vocal cords are angled and lie at level of C8

9. Trachea bifurcates at level of T9

Whole of larynx is lined by ciliated columnar epithelium except the vocal cords and upper part of vestibule which is lined by strati­fied squamous epithelium.

Mucous glands are distributed all over the larynx except the vocal cords, which is lubricated by mucus from glands within the sac­cule. The squamous epithelium of vocal fold is, therefore prone to desiccation if these glands cease to function as in radiotherapy.

Infant’s larynx differs from adult in:

• It is situated high up (C2 – C4).Q (in adults = C3 – C6)
• Of equal size in both sixes (in adults it is larger in males)
• Larynx is funnel shaped
• The narrowest part of the infantile larynx is the junction of subglottic larynx with trachea and this is because cricoid cartilage is very small
• Epiglottis is omega shaped, soft, large and patulous.
• Laryngeal cartilages are soft and collapse easily
• Short trachea and short neck.

• Vocal cords are angled and lie at level of C4
• Trachea bifurcates at level of T2
• Thyroid cartilage is flat. The cricothyroid and thyrohyoid spaces are narrow.

Tracheostomy in Infants and Children                                                                                                              

Trachea of infants and children is soft and compressible and its identification may become difficult and the surgeon may easily displace it and go deep or lateral to it injuring recurrent laryngeal nerve or even the carotid.

During positioning, do not extend too much as this pulls structures from chest into the neck and thus injury may occur to pleura, innominate vessels and thymus or the tracheostomy opening may be made twoo low near suprasternal notch

Tracheostomy in Infants and Children                                                                                               

The incision is a short transverse one, midway between lower border of thyroid cartilage and the suprasternal notch. The neck must be well extended.

A incision is made through two tracheal rings, preferably the third or fourth.

Ans. A i.e. Stratified squamous non-keratinized

The skeletal supports of larynx is provided by Six cartilages, 3 out of which are paired (so there are total 9 cartilages).

i) Unpaired :- Thyroid, cricoid, epiglottis.

ii) Paired :- Arytenoid, Corniculate, cuneiform.