Superficial lateral neck dissection with exposure of parotid and submandibular glands. The landmark muscle of the lateral neck, the sternocleidomastoid, borders the right edge of this image. Its proximal portion is overlaid by the parotid gland whose apex extends over the angle of the mandible. The gland also covers part of the masseter muscle. Below the body of the mandible is the submandibular gland filling much of the submandibular triangle whose other borders include the anterior and posterior bellies of the digastric muscle. The floor of this triangle contains the mylohyoid muscle anteriorly and the hyoglossus muscle (obscured by the gland) posteriorly. These two muscles attach to the hyoid bone from above. The infrahyoid muscles include the sternohyoid, superior belly of omohyoid, sternothyroid, and thyrohyoid. The latter two muscles attach to the oblique line of the thyroid cartilage of the larynx as does part of the inferior pharyngeal constrictor muscle. Just anterior to the sternocleidomastoid and also obscured by it is the internal jugular vein, common carotid, and internal carotid arteries. The vein receives the common facial vein or trunk, which, in turn is formed by union of the anterior branch of the retromandibular vein and lingual vein. Normally, it also receives the facial vein (removed) that leaves the face and crosses superficial to the submandibular gland. The origin of the external carotid artery is crossed superficially by the hypoglossal nerve coursing toward the floor of the oral cavity and the tongue. (Image courtesy of PA Rubino)