Dialogue with Residents: Surgical Approaches to Nasopharynx (With particular reference to Juvenile Nasopharyngeal Angiofibroma)

 Juvenile nasopharyngeal angiofibroma (JNA) is a rare, benign, vascular neoplasm that accounts for less than 0.5% of all head and neck tumors. JNAs occur almost exclusively in the nasopharynx of adolescent males.  The site of origin of JNA remains controversial. Some believe that it takes origin from the superior lip of the sphenopalatine foramen at the junction of the pterygoid process of the sphenoid bone and the sphenoid process of the palatine bone. Others claim that it arises from the bone of the vidian canal.  JNAs are slow growing and initially expand intranasally into the nasopharynx and nasal cavity and then into the pterygomaxillary space. Over time, JNAs will eventually erode bone and invade the infratemporal fossa, orbit, and middle cranial fossa.  The blood supply to these benign tumors is most commonly from the internal maxillary artery, but may also be supplied by the external carotid artery, the internal carotid artery, the common carotid artery, or the ascending pharyngeal artery.  Histologically, JNAs originate from myofibroblasts. The tumor lacks a capsule and spreads submucosally. It is composed of a fibrous abundance of single endothelial cell lined vascular spaces or channels.These channels are surrounded by a collagenous tissue network and lack a complete muscular layer.