Inferior laryngeal artery
Arteria laryngea inferior
Definition
The inferior laryngeal artery (arteria laryngea inferior) is a terminal branch of the inferior thyroid artery, itself arising from the thyrocervical trunk of the subclavian artery. It is the principal vessel responsible for the arterial supply to the inferior half of the larynx, complementing the superior laryngeal artery (from the superior thyroid artery), which supplies the upper half.
Course: The inferior laryngeal artery ascends alongside the recurrent laryngeal nerve (RLN) in the tracheoesophageal groove, providing vascular supply to the RLN along its distal course. It enters the larynx by passing deep to the inferior border of the inferior pharyngeal constrictor muscle, posterior to the cricothyroid articulation — mirroring the entry point of the RLN. Within the larynx, it ramifies to supply the subglottic structures and intrinsic laryngeal musculature.
Key anatomical relationships:
The artery maintains a close neurovascular relationship with the recurrent laryngeal nerve, serving as its distal vascular supply (while the esophageal and tracheal branches of the inferior thyroid artery supply the RLN more proximally).
It gives off a cricothyroid artery (also termed the paracommissural branch), which traverses the cricothyroid membrane just below the anterior commissure and anastomoses with the antero-inferior artery (a branch of the superior laryngeal artery) via transverse anastomotic networks at the glottic plane. This anastomosis was documented in 91% of cadaveric specimens.
Feature | Details |
Origin | Terminal branch of the inferior thyroid artery (from the thyrocervical trunk of the subclavian artery) |
Course | Ascends in the tracheoesophageal groove alongside the recurrent laryngeal nerve; enters the larynx posterior to the cricothyroid joint, deep to the inferior constrictor |
Branches | 1. Cricothyroid artery (paracommissural branch): penetrates the cricothyroid membrane below the anterior commissure; anastomoses with the antero-inferior artery (from the superior laryngeal artery) |
2. Tracheal branches: supply the upper tracheal rings and posterior tracheal wall; contribute to the lateral longitudinal tracheal anastomosis | |
3. Esophageal branches: supply the cervical esophagus adjacent to the tracheoesophageal groove | |
4. Muscular branches: supply the intrinsic laryngeal muscles (posterior cricoarytenoid, lateral cricoarytenoid, thyroarytenoid, interarytenoid) | |
Territory of supply | Subglottic mucosa and submucosa (from 1 cm below the ventricle apex to the inferior border of the cricoid cartilage) |
Intrinsic laryngeal muscles of the inferior larynx (all except the cricothyroid, which is supplied by the external branch of the superior laryngeal artery) | |
Posterior glottic region (via anastomoses with the superior laryngeal artery system) | |
Recurrent laryngeal nerve (vasa nervorum to the distal RLN) | |
Upper tracheal rings and adjacent cervical esophagus | |
Anastomoses | With the superior laryngeal artery system at the glottic plane (via the antero-inferior artery and transverse anastomotic networks); with the contralateral inferior laryngeal artery across the posterior midline |
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