cricoid

The Larynx

The larynx is an extremely important structure involved in vocalisation and protection of the lower airways during swallowing.

Here’s my simplification of the cartilages in the larynx (excuse my poor colouring skills):

Rostral to Caudal (front to back):

Epiglottis - seals the airways during swallowing - when inserting an ET into a patient, the epiglottis is flipped down so the arytenoid cartilages and the airway between them can be seen.

Arytenoid cartilages - Is paired - has muscular attachments to the vocal folds (vocal cords in humans) so is involved in vocalisation - paralysis of these muscles due to nerve damage results is a “roaring” sound, particularly in horses which can be corrected with surgery to tie the cartilage back against the laryngeal wall to hold the airway open.

Thyroid cartilage

Cricoid cartilage - singular

Basic Nerve supply:

Recurrent laryngeal - Caudal larynx 

Cranial laryngeal - Rostral larynx

Special Differences 

Rabbits and cats have sensitive laryngeal mucosa leaving them susceptible to laryngeal spasms. This is why vets use a local anaesthetic spray before intubating.