Juvenile Nasopharyngeal Angiofibroma (JA)
- JA typically presents with unilateral nasal obstruction/epistaxis and almost exclusively in male patients aged between 10-25 years of age.
- It is an unencapsulated highly vascular polypoidal mass of angiomatous tissue within a fibrous stroma. Biopsy should be avoided due to the risk of haemorrhage.
- The mass originates at the sphenopalatine foramen and is centered on the posterior wall of the nasal cavity, off the midline. It typically spreads early to the pterygopalatine fossa.
- Other routes of spread include extension into the nasal cavity, nasopharynx, sphenoid/maxillary/ethmoid sinuses, masticator space/infratemporal fossa, inferior orbital fissure. It can also extend into the cavernous sinus and into the middle cranial fossa.
- Key Diagnostic Features: Soft tissue mass with avid enhancement centered in the pterygopalatine fossa with spread into adjacent structures as outlined earlier. Posterior wall of the maxillary sinus is classically bowed anteriorly, and there can be a combination of bone remodelling +/- destruction. Flow voids may be seen on MR. On angiogram, tumor blush is seen, with feeders from the internal maxillary and ascending pharyngeal arteries.
- DDx: sinonasal haemangioma; rhabdomyosarcoma; polyp; esthesioneuroblastoma
- Rx: preoperative embolization followed by complete surgical resection
