An Anatomical Structure of the Superior Laryngeal Nerve of a Human Male

Description

Originating from the vagus nerve (cranial nerve X) high in the carotid triangle, the superior laryngeal nerve descends medial to the sternocleidomastoid and in close relationship to the carotid sheath, with the internal jugular vein and common carotid artery flanking it laterally and medially. Soon after its origin, the nerve divides into the internal branch, which courses anteromedially toward the thyrohyoid membrane with the superior laryngeal artery, and the external branch, which tracks inferiorly along the inferior pharyngeal constrictor toward the cricothyroid muscle. Surrounding landmarks in the neck and shoulder region logically include the hyoid, thyroid cartilage, laryngeal framework, clavicle, and upper cervical vertebrae, with superficial and infrahyoid musculature layered over the neurovascular bundle. Relationships matter here. This course explains several high-stakes clinical problems in anterior neck surgery. Ligation of the superior thyroid artery during thyroidectomy can endanger the external branch of the superior laryngeal nerve as it approaches the superior pole, producing cricothyroid weakness with loss of high-pitch phonation and early vocal fatigue, a complaint often reported by professional voice users. The internal branch is the primary sensory supply above the vocal folds, so injury or local anesthesia at the level of the thyrohyoid membrane alters the laryngeal cough reflex and raises aspiration risk, a point that ties directly to superior laryngeal nerve blocks for awake airway procedures. Use this artwork in head and neck anatomy teaching for the vagus nerve branches, in otolaryngology and endocrine surgery texts illustrating nerve-at-risk zones, or in clinical education on dysphonia after thyroid or carotid interventions. It also supports radiology and ultrasound discussions of the carotid space by anchoring the superior laryngeal nerve to consistent vascular and muscular landmarks. Anatomical accuracy verified by SciePro's Medical Advisory Board.