[Endoscopic Transoral Retropharyngeal Lymphadenectomy]

The aim of this study is to explore the anatomy and surgical approach of retropharyngeal lymphadenectomy via endoscopic transoral approach. The retropharyngeal spaces were studied with three fresh frozen cadaver head （6 sides） in the anatomical laboratory of Eye, Ear, Nose and Throat Hospital of Fudan University through endoscopic transoral approach. The superior pharyngeal constrictor muscle, medial pterygoid muscle, tendon of tensor veli palatini muscle, fat of prestyloid space, ascending palatine artery and its branches, styloglossus, stylopharyngeus, stylohyoideus, external carotid artery, levator veli palatini, carotid sheath, ascending pharyngeal artery and longus capitis muscle were revealed in order. The above-mentioned structures were photographed with a 0° Karl Storz nasal endoscope and adjacent relationships were recorded. A case of metastatic retropharyngeal lymphadenopathy was reviewed and the surgical methods and techniques of retropharyngeal lymphadenectomy via endoscopic transoral approach were introduced in detail. The retropharyngeal space and related anatomical structures were exposed through endoscopic transoral approach in all specimens. The styloglossus, stylopharyngius and levator veli palatini are the markers of locating the internal carotid artery. The superior pharyngeal constrictor muscle, medial pterygoid muscle, styloid muscle group, longus capitis muscle and carotid sheath are the markers that can be used to locate the retropharyngeal lymph nodes. Ascending palatine artery, ascending pharyngeal artery and internal carotid artery are the main arteries involved in retropharyngeal lymphadenectomy via endoscopic transoral approach. Endoscopic transoral approach is a new surgical technique to perform retropharyngeal lymphadenectomy safely and completely.