Left Lateral Deep Neck, Suboccipital, and Pharyngeal Wall Dissection
6211
Surgical Correlation
Tags
Left lateral deep neck, suboccipital, and pharyngeal wall dissection. The ramus of the mandible and zygomatic arch have been removed along with the pterygoid muscles to provide a view of the lateral pharyngeal wall area. The lateral pterygoid plate is exposed. The tensor veli palatini muscle descends along the lateral surface of the medial pterygoid plate and the tendon of this muscle passes around its bony hamulus enroute to the soft palate. Just deep and slightly posterior to the tensor muscle is the levator veli palatini, which also inserts into the soft palate. It is overlapped inferiorly by the upper border of the superior pharyngeal constrictor muscle (partially cut). Overlying this portion of the constrictor muscle are the ascending palatine branch of the facial artery and the ascending pharyngeal artery, a medial branch of the external carotid. The mandibular nerve gives rise to several branches, including the inferior alveolar nerve to the lower jaw, the lingual nerve to the tongue, buccal nerve to the skin and mucous membrane of the cheek, and auriculotemporal nerve whose roots enclose the middle meningeal artery. The styloid process gives rise to three muscles: stylohyoid, styloglossus, and stylopharyngeus. The internal jugular vein is seen descending in the neck and is crossed proximally by the spinal accessory nerve to the sternocleidomastoid and trapezius muscles. Anterior to it is the external carotid artery that has given off the facial, occipital, maxillary, superficial temporal, and ascending pharyngeal branches. The hypoglossal nerve is shown descending in the neck and bending forward along the superficial surface of the hyoglossus muscle before passing deep to the mylohyoid muscle to enter the floor of the mouth. C1 fibers enclosed in the epineurium leave the hypoglossal nerve as the superior root of the ansa cervicalis to supply strap (infrahyoid) muscles. Posterior to the internal jugular vein and deep within the neck are the suboccipital muscles (obliquus capitis inferior, obliquus capitis superior, rectus capitis posterior major), their nerve supply, the suboccipital nerve, and the large sensory nerve to the posterior scalp, the greater occipital nerve. These are covered by the semispinalis capitis muscle and then by the splenius capitis and cervicis muscles. (Image courtesy of AL Rhoton, Jr.)