Subglottic

Subglottic refers to the subglottis, the portion of the larynx located below the vocal folds (glottis) and above the cricoid cartilage. It extends from the inferior surface of the vocal cords to the inferior border of the cricoid cartilage and contains the subglottic space through which air passes on its way to the trachea.

Anatomy and histology in this region include the mucosal lining of the larynx, which is typically respiratory epithelium with submucosal glands. The subglottic area is continuous with the trachea inferiorly and shares similar mucosal characteristics. The blood supply comes from branches of the superior and inferior thyroid arteries, with venous drainage to the thyroid and nearby venous systems. Innervation is primarily through the inferior laryngeal nerve, a terminal branch of the recurrent laryngeal nerve, providing sensory innervation to the subglottic mucosa and motor innervation to intrinsic laryngeal muscles via other branches.

Clinically, the subglottic region is important because disease in this area can affect the upper airway. Subglottic stenosis, for example, is a narrowing that can be congenital or acquired (often related to intubation, trauma, infection, or inflammatory disease). In infants and young children, the subglottic region is the narrowest part of the pediatric airway, making it particularly susceptible to obstruction from edema or infection such as croup. Diagnosis typically involves imaging and endoscopic examination, with management ranging from medical therapy for inflammation to endoscopic dilation or surgical procedures such as laryngotracheoplasty in cases of significant stenosis.