The anteroposterior diameter of the newborn glottis is 7 mm, and the transverse diameter of the posterior end is 4 mm. If the former is less than 5 mm and the latter is less than 3 mm, it is considered congenital small larynx. The internal structure of a congenital small larynx is normal, but due to the narrow laryngeal cavity, severe cases often cannot maintain normal ventilation.

bubble_chart Clinical Manifestations

A slightly small larynx usually has no symptoms, but inflammation can cause laryngeal obstruction. A significantly small larynx may present with laryngeal stridor and breathing difficulties from birth, with symptoms similar to subglottic stenosis.

bubble_chart Diagnosis

Direct laryngoscopy revealed that all laryngeal structures were smaller, with a short and narrow glottis. Palpation of the neck showed the thyroid cartilage to be smaller than normal.

bubble_chart Treatment Measures

Asymptomatic individuals do not require treatment but should focus on preventing the common cold and other pains. If experiencing difficulty breathing, a tracheostomy should be performed. After the procedure, the tube should be blocked multiple times to encourage breathing through the larynx as much as possible, promoting laryngeal development.